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1.
A multitrait animal model was used to calculate predicted transmitting ability and reliabilities for final score and 15 linear type traits of 225,632 US Jersey cows. Records were adjusted for age and stage of lactation before analysis. The model contained effects for interactions of herd and date scored; year scored, parity, and age; and herd and sire; effects of permanent environment and additive genetics were also included. Of the 381,511 records included, some observations were missing for final score (8%), body depth (43%), and teat length (33%). The evaluation system used a canonical transformation, included several random effects, and estimated missing values with each iteration. Inbreeding was considered in the computations. Convergence was achieved in approximately 50 rounds of iteration. Correlations between animal and sire model predicted transmitting ability ranged from 0.56 to 0.95 and generally were higher for bulls than for cows and for more recent birth years. Genetic trend was strongly positive for dairy form, final score, and rear udder traits (height and width) and negative for udder depth. For other traits, genetic trend was small. This methodology should improve the accuracy of genetic evaluations for type traits of US Jerseys.  相似文献   

2.
Scores for clinical lameness from two separate studies were combined, and genetic parameters were estimated based on linear and threshold models. Cows were from 24 herds in Minnesota, Wisconsin, and Virginia. To evaluate clinical lameness, cows were observed walking and were assigned a score between 0 and 4 (where 0 = no observable problems to 4 = inability to walk). Data included 1624 records on 1342 cows. The models included fixed effects of herd visit, parity, and stage of lactation. Random effects were additive genetics, permanent environment to account for repeated records, and residual. Estimates of heritability were 0.10 and 0.22 from the linear and threshold models, respectively. The correlation between ETA from linear and threshold models based on all animals was 0.974. Deregressed ETA of sires and REML were used to estimate genetic correlations between clinical lameness and conformation traits. Among the type traits, foot angle, rear legs (rear view), and rump width had strongest associations with clinical lameness; absolute values for genetic correlations between these traits and clinical lameness were approximately 0.65. Low foot angle, hocking in, and wide rumps were associated with increased clinical lameness. Correlations with strength and body depth ranged from 0.20 to 0.43, indicating that heavier cows were more prone to clinical lameness.  相似文献   

3.
Genetic and phenotypic parameters of body weight (BW), hip height, heart girth, and linear conformation traits were estimated from field data for 7344 lactating Holstein heifers from 560 herds. Mean BW was around 540 kg at calving, decreased to a minimum of 514 kg by wk 6, and increased to > 590 kg by wk 45 of lactation. The statistical model for BW included month of recording, lactation stage, pregnancy stage, proportion of Holstein genes, parity of the dam, calving age, herd, and animal. Variation between herds accounted for 33% of the phenotypic variation of BW. Estimated heritability was 0.33 for BW and ranged from 0.32 to 0.54 for heart girth, hip height, and conformation traits. Genetic correlations of BW with heart girth, hip height, body depth, rump width, and muscularity ranged from 0.48 to 0.77. The accuracy of a selection index was 0.90 for direct selection and 0.83 for indirect selection using information on those conformation traits of 50 daughters. Genetic variation of BW is considerable, and genetic evaluation of BW can be based on data for conformation traits from a field recording system with only a limited loss of accuracy.  相似文献   

4.
Quantitative trait loci affecting conformational type traits were studied in seven large grandsire families of US Holsteins using the granddaughter design and 16 microsatellite markers on 10 chromosomes. The most significant marker effect was marker BM203 (chromosome 27) for dairy form in a single grandsire family. A multivariate analysis for dairy form and milk yield was also conducted, and the result was highly significant, indicating that a segregating quantitative trait locus or loci affecting dairy form and milk yield could exist near BM203 on chromosome 27. Marker BM1258 (chromosome 23) had a significant effect on udder depth. A multivariate analysis on udder depth and somatic cell score was conducted for markers 513 and BM1258, and both markers showed significant effects on these two traits, indicating that one or several quantitative trait loci affecting udder depth and mastitis might exist on chromosome 23. Marker BM4204 (chromosome 9) had a significant effect on foot angle and on the composite index of traits pertaining to feet and legs, indicating that one or several quantitative trait loci affecting traits pertaining to feet and legs might exist on chromosome 9. Selection on these markers could increase genetic progress within these families.  相似文献   

5.
The Glasgow Coma Scale (GCS) is routinely used in the acute care setting after traumatic brain injury (TBI) to guide decisions in triage, based on its ability to predict morbidity and mortality. Although the GCS has been previously demonstrated to predict mortality, efficacy in prediction of functional outcome has not been established. The purpose of this study was to assess the value of the acute GCS in predicting functional outcome in survivors of TBI. This study used the Multicenter National Institute on Disability and Rehabilitation Research TBI Model Systems database of 501 patients who had received acute medical care and inpatient rehabilitation within a coordinated neurotrauma program for treatment of TBI. Initial and lowest 24 hr GCS scores were correlated with the following outcome measures: the Disability Rating Scale (DRS), Rancho Los Amigos Levels of Cognitive Functioning Scale (LCFS), and cognitive and motor components of the Functional Independence Measure (FIM(SM)-COG and FIM(SM)-M). Outcome data were collected at admission to and discharge from the inpatient TBI rehabilitation unit. Correlation analysis revealed only modest, but statistically significant, relationships between initial and lowest GCS scores and outcome variables. Initial and lowest GCS score comparison with outcome demonstrated the following correlation coefficients: admission DRS, -0.25 and -0.28; discharge DRS, -0.24 and -0.24; admission LCFS, 0.31 and 0.33; discharge LCFS, 0.27 and 0.25; admission FIM-COG, 0.36 and 0.37; discharge FIM-COG, 0.23 and 0.23; admission FIM-M, 0.31 and 0.31; discharge FIM-M, 0.25 and 0.21. The GCS as a single variable may have limited value as a predictor of functional outcome.  相似文献   

6.
Martensite reversion treatment was utilized to obtain ultrafine grain size in Fe-18Cr-12Mn-N stainless steels containing 0 to 0.44 wt pct N. This was achieved by cold rolling to 80 pct reduction followed by reversion annealing at temperatures between 973 K and 1173 K (700 °C and 900 °C) for 1 to 10seconds. The microstructural evolution was characterized using both transmission and scanning electron microscopes, and mechanical properties were evaluated using hardness and tensile tests. The steel without nitrogen had a duplex ferritic-austenitic structure and the grain size refinement remained inefficient. The finest austenitic microstructure was achieved in the steels with 0.25 and 0.36 wt pct N following annealing at 1173 K (900 °C) for 100 seconds, resulting in average grain sizes of about 0.240 ± 0.117 and 0.217 ± 0.73 µm, respectively. Nano-size Cr2N precipitates observed in the microstructure were responsible for retarding the grain growth. The reversion mechanism was found to be diffusion controlled in the N-free steel and shear controlled in the N-containing steels. Due to a low fraction of strain-induced martensite in cold rolled condition, the 0.44 wt pct N steel displayed relatively non-uniform, micron-scale grain structure after the same reversion treatment, but it still exhibited superior mechanical properties with a yield strength of 1324 MPa, tensile strength of 1467 MPa, and total elongation of 17 pct. While the high yield strength can be attributed to strengthening by nitrogen alloying, dislocation hardening, and slight grain refinement, the moderate strain-induced martensitic transformation taking place during tensile straining was responsible for enhancement in tensile strength and elongation.  相似文献   

7.
The objective of this study was to evaluate the importance of environment, management, physiological status, and genetics on semen quality (volume of the ejaculate, sperm concentration, sperm motility, number of sperm, and number of motile spermatozoa per ejaculate) of Canadian Holstein bulls. For this purpose, semen production data from 198 bulls were analyzed using mixed linear models. Young bulls (up to 30 mo old) and mature bulls (between 4 and 6 yr old) were analyzed separately. Semen characteristics generally improved significantly with age of young bulls. Season significantly affected all semen traits in young bulls but did not significantly affect volume and sperm motility of mature bulls. Performance was better in winter than in summer. The highest numbers of motile spermatozoa per ejaculate were obtained with intervals of at least 4 to 5 d between collections. Although the bull handler and semen collector caused less than 10% of the variance, the collection team significantly affected semen volume, number of sperm, and number of motile sperm per ejaculate for both growing and mature bulls. Heritabilities for volume, concentration, sperm motility, number of sperm, and number of motile sperm per ejaculate were, respectively, 0.24, 0.52, 0.31, 0.38, and 0.49 for young bulls and 0.44, 0.36, 0.01, 0.54, and 0.64 for mature bulls. Repeatability of semen traits varied from 0.41 to 0.64. Genetics, management, and environmental factors clearly contribute to semen production in Holstein bulls.  相似文献   

8.
The arch forms of 38 cases (53 nonextraction and 23 extraction arches) in which expansion, while maintaining arch form, was the objective of the practitioner, were analyzed before treatment, after treatment, and an average of 6 to 8 years after retention. The cubic spline was used to fit a curve representing arch form. By superimposing the spline curves, changes in arch form were analyzed with the variables rebound change (RC), rebound index (RI), rebound number (RN), and stability number (SN). Traditional linear intraarch dimensions were also analyzed. Analysis of variance was used to determine differences between the maxillary and mandibular arches and between the extraction and nonextraction cases. Pearson correlation coefficients between spline variables and arch width variables were also computed. There was significantly more expansion in the maxillary arch than the mandibular arch during treatment, irrespective of extraction or nonextraction strategies. In the nonextraction cases, a greater amount of net expansion was achieved for all dimensions for the maxillary arch as compared with the mandibular arch. Overall, a relatively high stability in arch form was found. The findings suggest that stability may not be related to the amount of change produced during treatment. Significant expansion can be gained throughout the premolar regions and may be expected to be stable. The order of greatest net arch width gained was for the second premolars followed by first premolars, molars, and then the canines. The intercanine widths for both arches decreased toward pretreatment values, but were more stable in the maxillary arch in nonextraction cases. The cubic spline permits measurement of change in arch form both during treatment and retention periods.  相似文献   

9.
In each of two trials, 160 commercial pullets were separated into four treatments with four replicates of 10 chickens in each treatment. Forty pullets were designated as controls and received no inoculation; 40 other pullets received F strain Mycoplasma gallisepticum (FMG); an additional 40 pullets received Mycoplasma synoviae (MS); and the final 40 pullets were inoculated with both FMG and MS (dual). Hen-day egg production, egg weight, eggshell strength, Haugh unit score, pimpling incidence, and blood/meat spot incidence were monitored and recorded in each trial through an entire laying cycle. No significant difference was observed among the treatments for hen-day egg production, egg weight, eggshell strength, or Haugh unit scores. Significant differences were observed for pimpling incidence among controls (1.63%), Mycoplasma gallisepticum (MG)-infected (2.09%), and dual-infected hens (2.41%). A significant difference in blood/meat spot incidence was observed between MG-infected hens (0.27%) and dual-infected hens (0.45%). Histopathologic examination of the ovary and all segments of the oviduct revealed no significant differences among the treatments. These results suggest that the majority of the hen reproductive tract functions similarly in FMG-vaccinated, MS-infected, or dual-infected hens as compared with Mycoplasma-clean hens.  相似文献   

10.
OBJECTIVE: To analyze the relationship among metabolic control, IGF-I, and growth in pubertal diabetic subjects. RESEARCH DESIGN AND METHODS: In 72 diabetic children, we have studied the pattern of change of IGF-I, IGF-I SD score, IGF binding protein (BP)-1, and growth rate in different pubertal stages and have analyzed their relation to age sex, weight/length index, HbA1c, insulin concentration, insulin dose, and dehydroepiandrosteronesulfate (DHEAS). RESULTS: The serum IGF-I values increased up to Tanner stage 4 and thereafter decreased, whereas IGFBP-1 showed the inverse pattern. When transforming the IGF-I values into SD scores, correcting for age, sex, and pubertal stage, it was shown that the deviation from normal values increased with increasing pubertal stage in boys, but was equal in stages 3-5 in girls. Using multiple regression analysis, HbA1c, insulin dose, and DHEAS were significantly correlated to IGF-I SD score (R2 = 0.253, P = 0.001). IGFBP-I levels in the afternoon were within normal range. LogIGFBP-1 showed an inverse correlation, to insulin concentration in single correlation (r = -0.26, P = 0.02). In single correlation, growth rate correlated significantly to insulin dose (r = 0.25, P = 0.03). In a multiple regression analysis, only DHEAS and IGF-I SD score were found to be significantly correlated to growth rate (R2 = 0.370, P < 0.001). The 18 adolescents who had reached their final height did not deviate from their target final height, according to their recorded growth since birth. CONCLUSIONS: In a group of fairly well-controlled diabetic children, the normal increase in IGF-I during puberty is blunted. Despite decreased IGF-I levels, target final height was attained, probably because of adequate insulin compensation leading to normal IGFBP-l, thus adequate bioavailability of IGF-I. Our results point out the importance of sufficient exogenous insulin in the period of rapid linear growth.  相似文献   

11.
AIM: To compare the growth of very low birthweight (VLBW) children in early adolescence with that of their normal birthweight peers; to examine the role of factors contributing to growth-parental height, perinatal variables, bone maturity and sexual maturation; to examine the correlation between head growth and cognitive and educational outcome. METHODS: Standing and sitting heights, weight, occipito-frontal circumference (OFC), skinfold thicknesses and pubertal staging were assessed in 137 VLBW children and 160 controls at 11-13.5 years of age. Ninety six (70%) of the VLBW children had their bone age assessed using the TW2 method. Reported parental heights were obtained by questionnaire. All children had standardised tests of cognitive and educational ability. Perinatal data had been collected prospectively as part of a longitudinal study. RESULTS: VLBW children had lower heights, weight, and OFC. Skinfold thicknesses were no different. The children's short stature was not accounted for by difference in parental height, degree of pubertal development, or by retarded bone age. Indeed, the TW2 RUS score was significantly advanced in the VLBW children. Using the bone ages to predict final adult height, 17% have a predicted height below the third centile and 33% below the tenth. Weight was appropriate for height, but there was a residual deficiency in OFC measurements after taking height into account. In the VLBW group smaller head size was associated with lower IQ and mathematics and reading scores. CONCLUSIONS: Growth problems persist in VLBW children and final heights may be even more abnormal than present heights suggest. VLBW children have smaller OFCs than expected from their short stature alone and this may be associated with poorer educational and cognitive outcomes.  相似文献   

12.
The model of 25 children with mild Class II, Division 1 malocclusions who had their upper buccal segments moved distally with an en masse appliance were measured at the beginning of treatment and at the completion of buccal segment retraction. A reflex microscope, interfaced to a personal computer, was adapted for this purpose. A custom-made jig and linear stepping motor permitted the recording of both buccal and incisal measurements of the teeth in occlusion, as well as individual arch parameters. Software was designed to record and calculate the required measurements. The method error associated with this approach ranged from 0.01 to 0.5 mm. Results indicated that mean distal movement of the buccal segments approximated 6 mm, equivalent to a full cusp of buccal segment retraction. A small spontaneous reduction in overjet was seen. The upper arch showed spontaneous alignment and increases in width, length, and perimeter. In the lower jaw, transverse expansion was accompanied by a small increase in arch perimeter. Arch length, however, was slightly reduced. It was concluded that the system was an acceptable method of recording occlusal changes during orthodontic treatment, supplementing routine cephalometry. Furthermore, a full unit of buccal segment retraction could be expected, by using a removable appliance/headgear technique.  相似文献   

13.
The objective of this study was to review some of the latest evidence of genetic variation in feed intake and feed utilization and to determine how this variation might be used. The most important sources of genetic variation in gross efficiency are likely to be the quantities of feed eaten and used for yield or maintenance and the extent to which body tissue is mobilized. Accounting for just one of these components when selection is for improved feed efficiency might result in undesirable genetic changes. For example, in an ad libitum feeding system, the heritability of body condition score is reported to be 0.43 for heifers; genetic correlations of body condition score with milk production and live weight were -0.46 and 0.66, respectively. Also, the genetic correlation between milk yield and live weight depends on lactation stage. For example, over the first 26 wk of lactation, this correlation was reported to be -0.09, but, after genetic adjustment for body condition score, the correlation was 0.29. When economic values are being derived, energy norms or genetic correlations can be used, and double counting of the feed costs needs to be avoided. An index that contained linear type traits, however, gave high accuracy of selection. Hence, although there appears to be great potential to improve economic efficiency by selecting for feed intake and live weight or by possible indicator traits, there is still uncertainty about some of the genetic parameters, especially among traits related to health, reproduction, and energy balance.  相似文献   

14.
Growth acceleration and bone maturation were studied for 3 y in 69 children with severe short stature and a history of intrauterine growth retardation (IUGR), to determine the effect of treatment with recombinant human growth hormone (r-hGH). The patients were enrolled in an open, multicentre trial and were randomly allocated to either the treated group (Group 1) or the control group (Group 2). The children in Group 1 were treated daily with 0.2 IU/kg/body weight (0.067 mg/kg) s.c., during 3 y and the children in Group 2 started the study with a 1-y observation period followed by a 3-y treatment period. At birth, their mean weight standard deviation score (SDS) was -2.5 and their mean length SDS -3.5. At baseline, the patients were prepubertal, non-GH deficient, with no known dysmorphic features. Mean age was 4.5 y, bone age was 3.3 y, height SDS was -3.4, height velocity (HV) SDS was -1.6, and body mass index SDS was -1.4. After 1 y of treatment, linear HV in Group 1 increased in comparison with the pre-treatment period (from 5.7 +/- 2.0 to 10.1 +/- 1.7 cm/y; p < 0.001) and with the first year of observation in Group 2 (p < 0.001). Increased HV was sustained during the second and third year of treatment and was significantly higher than at baseline. A similar growth pattern was seen during the 3 y of GH treatment in Group 2. Mean height SDS for chronological age increased by 2.0 +/- 0.7 in the two groups after 3 y of treatment. HV after 1 y of treatment was negatively correlated with growth velocity at baseline. Bone age remained retarded but increased with a mean of almost 4 y after 3 y of treatment in both groups. Even at a dose that is three times the replacement dose treatment with r-hGH was well tolerated. From these results, we conclude that r-hGH treatment over 3 y can induce sustained catch-up growth in young children with severe short stature and a history of IUGR. Long-term studies are needed to assess ultimate effects on final height.  相似文献   

15.
In the future, the Pasteurized Milk Ordinance may make milk quality standards more stringent by lowering the somatic cell count (SCC) limit on Grade A raw milk to 500,000/ml. Therefore, using a discrete event simulation model, we investigated the effects of the prevention of intramammary infection (as recommended by the National Mastitis Council), lactation therapy, and dry cow therapy (all seven possible combinations) on bulk tank SCC; milk, fat, and protein yields; prevalence of intramammary infection; and culling for mastitis. Untreated controls were also tested. Ten replicates of each intervention and each control were run for 2 simulated yr, including the daily sampling of 100 cows. The goal was to lower bulk tank SCC < 500,000/ml in the 2nd yr for herds that previously had stable bulk tank SCC between 500,000 and 750,000/ml. Although all strategies occasionally met this goal, on no occasion did all replicates perform without a violation in the 2nd yr of the study (median last month of violation ranged from mo 12 to 23). The combination of the prevention of intramammary infection, lactation therapy, and dry cow therapy resulted in the lowest bulk tank linear score, most replicated without a violation in the 2nd yr, fewest months with a bulk tank linear score > or = 5.3, and fewest mastitis culls. The combination of the prevention of intramammary infection and dry cow therapy also was favorably ranked (highest milk yield, fewest clinical intramammary infections during lactation, and highest percentage of uninfected cows).  相似文献   

16.
In this study an attempt was made to find an optimum method of chemical treatment to prevent the calcification of bioprosthetic heart valves. Bovine pericardium was washed in a 5% sodium chloride solution followed by trypsin (Tr) treatment and was kept in 0.1% glutaraldehyde (GA) with a gradual increase in concentration up to 0.25% GA and finally posttreated with a 4% chitosan (Ch) solution. Fresh, 0.2% GA, 0.625% GA, and sodium chloride-Tr-GA treated pericardial samples were taken for comparative study. Tensile testing showed comparable strength and elongation at the breaking point for all groups. The thermal shrinkage studies indicated merit of the proposed treatment (5% sodium chloride-trypsin-glutaraldehyde treated pericardia with chitosan and without chitosan posttreatment). Collagenase assay showed that all differently treated (GA) materials were equally resistant to collagenase. All samples were implanted subcutaneously in rats for 2, 4, 8, or 12 weeks for calcification study. Morphological and mineral analyses showed complete prevention of calcification in sodium chloride-trypsin-GA-chitosan treated pericardium (Ca was 1.1 +/- 0.27 mg/g, von Kossa 0) at the 12th week of implantation.  相似文献   

17.
Rigid spherical particles in the size range of 5-200 nm diameter were subjected to capillary zone electrophoresis (CZE) in semidilute solutions of uncross-linked polyacrylamide of M(r) 5, 7 and 18 x 10(6) (PA-5, -7 and -18, respectively) of varying concentrations up to 1.6% and at field strengths varying from 68 to 270 V/cm. For all particles under study, the experimental Ferguson plots, log(mobility) vs. polymer concentration, permit a linear approximation. Their slope, the retardation coefficient KR = delta log (mobility)/delta (concentration), for particles smaller than 30 nm in diameter increased with particle size in PA-5 and -7 independently of electric field strength and polymer M(r). The KR of particles of 30 nm in diameter or more was found to be independent of particle size at the lowest field strength used but to decrease with it at the higher values of field strength. The decrease was parallel but shifted to higher values of retardation when the polymer M(r) increased from 5 to 7 x 10(6). With a decreasing ratio of average mesh size of the polymer network, zeta, to particle radius, R, the approach to "continuity" of the polymeric medium (zeta/R < 1) with both increasing particle size and polymer concentration does not result in the retardation behavior expected according to the macroscopic (bulk) viscosity of the solution. These experimental observations were hypothetically interpreted in terms of a transition to a retardation mechanism comprising the formation of a polymer depletion layer near the particle surface--polymer solution interface. Peak width exhibited an overall increase with PA-7 concentration for all particles studied. For particles of 30 nm in diameter or less, the increase was steepest when the radius of the particle was approximately commensurate with zeta at a given polymer concentration. For the largest particle, 205 nm in diameter, peak broadening with polymer concentration was found to correlate linearly with peak asymmetry. CZE of the particles in PA-18 solutions revealed abnormal behavior, with both mobility and peak width remaining near-constant up to a concentration of 0.08% and sharply declining at higher concentrations. The decline of relative mobility is the same-for the entire particle size range used, while peak width declines in direct relation to particle size.  相似文献   

18.
Effects of methyltestosterone on insulin secretion and sensitivity in women   总被引:2,自引:0,他引:2  
The frequent coexistence of hyperandrogenism and insulin resistance is well established; however, whether a cause and effect relationship exists remains to be established. In this study we tested the hypothesis that short-term androgen administered to women would induce insulin resistance. To test this hypothesis, regularly menstruating, nonobese women were studied before and during methyltestosterone administration (5 mg tid for 10-12 days) by the hyperglycemic (n=8) and euglycemic, hyperinsulinemic (n=7) clamp techniques. Short-term methyltestosterone administration had no significant effects on the fasting levels of glucose, insulin, c-peptide, glucagon, or glucose turnover. During the hyperglycemic clamp studies, the mean glucose level during the final hour was 203+/-2 and 201+/-1 mg/dL in the methyltestosterone and control studies, respectively. The insulin response to this hyperglycemic challenge was slightly but not significantly greater during methyltestosterone treatment (first phase 59+/-8 vs. 50+/-8 microU/mL in controls; second phase 74+/-9 vs. 67+/-9 microU/mL in controls; total insulin response 133+/-16 vs. 117+/-15 microU/mL in controls). In spite of this, glucose uptake was reduced from the control study value of 10.96+/-1.11 to 7.3+/-0.70 mg/kg/min by methyltestosterone (P < 0.05). The ratio of glucose uptake per unit of insulin was also significantly reduced from a control study value of 14.3+/-1.4 to 9.4+/-1.3 mg/kg/min per microU/mL x 100 during methyltestosterone administration. In the euglycemic hyperinsulinemic clamp studies, insulin was infused at rates of 0.25 and 1.0 mU/kg/min to achieve insulin levels of approximately 25 and 68 microU/mL, respectively. During low-dose insulin infusion, rates of endogenous hepatic glucose production were equivalently suppressed from basal values of 2.37+/-0.29 and 2.40+/-0.27 mg/kg/min to 0.88+/-0.25 and 0.77+/-0.26 mg/kg/min in the methyltestesterone and control studies respectively. Whole body glucose uptake during low-dose insulin infusion was minimally affected. During the high-dose insulin infusion, endogenous hepatic glucose production was nearly totally suppressed in both groups. However, whole body glucose uptake was reduced from the control value of 6.11+/-0.49 mg/kg/min to 4.93+/-0.44 mg/kg/min during methyltestosterone administration (P < 0.05). Our data demonstrate that androgen excess leads to the development of insulin resistance during both hyperglycemic and euglycemic hyperinsulinemia. These findings provide direct evidence for a relationship between hyperandrogenemia and insulin resistance, and its associated risk factors for cardiovascular disease.  相似文献   

19.
High sucrose diets alter mineral metabolism in humans and animals. We examined the effect of a high sucrose diet on bone growth, composition and mechanical strength in growing rats. Weanling Wistar rats received a high sucrose (43 g/100 g) diet (9 males, 11 females). In the control diet (8 males, 8 females), sucrose was replaced with potato starch, providing an equal energy value. At the onset of the experiment, bones were marked by tetracycline. After 5 wk, the tibias and femurs were weighed, and maximum breaking strengths were determined. Tibias were cut at the tibia-fibular junction; the widths of the bone at the start of the experiment, the periosteal bone formation during the experiment, the widths of the medullary cavity and the final bone width were determined from tetracycline lines. Bone ash weight, Ca and P contents were determined. The breaking strengths of both bones were significantly lower in the sucrose-fed groups of both sexes. In females, the weight of both bones and the final width of the tibias were significantly lower in the sucrose-fed group. The Ca concentration in both bones and the P concentration in tibias were significantly lower in the sucrose-fed group. It was concluded that the metabolic interference induced by sucrose was the reason for the differences. The alterations were more pronounced in females, but independent of body weight.  相似文献   

20.
A total of 74 children suffering from acute lymphoblastic leukaemia (ALL) or non-Hodgkin lymphoma (NHL) were involved in a retrospective analysis of their physical growth during and after the therapy. Out of this total number, 54 children were subjected to radiochemotherapy in compliance with the VII/(81) scheme, and another 20 children in compliance with the LSA2L2 scheme. At the beginning of the therapy the average height-standard deviation score (H-SDS) for both groups of patients corresponded with the population average. The patients subjected to the VII/(81) scheme showed, throughout the observation period of five years from the beginning of the therapy, a height normal for their age group. Contrary to this observation, the patients subjected to the LSA2L2 scheme experienced a significantly different growth in the period under observation and continually lost height in comparison to the normal population. The same results were experienced with a smaller group of patients whose growth was followed up for eight years from the beginning of therapy. 16 patients (VII/81 n = 4/LSA2L2 n = 12) reached their final height. For the patients of the VII/(81) scheme the final height showed an average H-SDS of 0.27 and for the patients of the LSA2L2 scheme of -1.22 (p = 0.068). Considering that the same cranial radiotherapy (max. 18 Gy for both schemes) and a comparable intensive induction therapy were applied, it must be concluded that the intensity and duration of the maintenance treatment are the critical factors initiating a different growth behaviour of the two groups subjected to radiochemotherapeutical schemes.  相似文献   

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