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91.
Dechow CD Rogers GW Sander-Nielsen U Klei L Lawlor TJ Clay JS Freeman AE Abdel-Azim G Kuck A Schnell S 《Journal of dairy science》2004,87(10):3526-3533
The objectives of this study were to estimate genetic correlations among body condition scores (BCS) from various sources, dairy form, and measures of cow health. Body condition score and dairy form evaluated during routine type appraisal was obtained from the Holstein Association USA, Inc. A second set of BCS was obtained from Dairy Records Managements Systems (DRMS) and was recorded by producers that use PCDART dairy management software. Disease observations were obtained from recorded veterinarian treatments in several dairy herds in the United States. Estimated breeding values for diseases in Denmark were also obtained. Genetic correlations among BCS, dairy form, and cow health traits in the United States were generated with sire models. Models included fixed effects for age, DIM, and contemporary group. Random effects included sire, permanent environment, herd-year season for health traits, and error. Predicted transmitting abilities (PTA) for BCS and dairy form were correlated with estimated breeding values for disease in Denmark. The genetic correlation estimate between BCS from DRMS and BCS from the Holstein Association USA, Inc., was 0.85. The genetic correlation estimate between BCS and a composite of all diseases in the United States was -0.79, and PTA for BCS was favorably correlated with an index of resistance to disease other than mastitis in Denmark (0.27). Dairy form was positively correlated with a composite of all diseases in the United States (0.85) and was unfavorably correlated with an index for resistance to disease other than mastitis in Denmark (-0.29). Adjustment for protein yield PTA had a minimal affect on correlations between PTA for BCS or dairy form and disease in Denmark. Selection for higher body condition or lower dairy form with continued selection for yield may slow deterioration in cow health as a correlated response to selection for increased yield. 相似文献
92.
Butter composition and texture from cows with different milk fatty acid compositions fed fish oil or roasted soybeans 总被引:1,自引:0,他引:1
Bobe G Zimmerman S Hammond EG Freeman AE Porter PA Luhman CM Beitz DC 《Journal of dairy science》2007,90(6):2596-2603
Changing the milk fatty acid composition can improve the nutritional and physical properties of dairy products and their acceptability to consumers. A more healthful milk fatty acid composition can be achieved by altering the cow's diet, for example, by feeding supplemental fish oil (FO) or roasted soybeans (RSB), or by selecting cows with a more unsaturated milk fatty acid composition. We examined whether feeding supplemental FO or RSB to cows that had a more unsaturated milk fatty acid composition acted additively to produce butter with improved fatty acid composition and texture. Using a 3 × 3 Latin square design with 2 replications, we fed diets to multiparous Holstein cows (60 to 200 DIM) chosen for producing either more or less unsaturated milk fatty acid composition (n = 6 for each group) for three 3-wk periods. The control diet contained 3.7% crude fat and the 2 experimental diets contained, on a dry matter basis, 0.8% of additional lipids in the form of 0.9% of FO or 5% of RSB. The milk, collected in the third week of feeding, was used to make butter, which was analyzed for its fatty acid composition and physical properties. Dry matter intake, milk yield, and milk composition were not significantly affected by cow diet or by cow selection. Cows that produced a more unsaturated and healthful milk fat prior to the feeding study, according to a “health-promoting index” [HPI = (sum of % of unsaturated fatty acids)/ (%12:0 + 4 × %14:0 + %16:0)], maintained a higher HPI in their butter during the feeding study than did cows with a low HPI. Milk from cows fed supplemental FO or RSB yielded more unsaturated butters with a higher HPI. This butter also was softer when the cows were fed RSB. Feeding RSB to cows chosen for their high milk HPI yielded the most unsaturated butter with the highest HPI and softest texture. Thus, selecting cows with a more health-promoting milk fatty acid composition and feeding supplemental RSB can be used in combination to produce butter that has a consumer-friendly texture and a healthful fatty acid profile. 相似文献
93.
CR Jacobs CE Yellowley BR Davis Z Zhou JM Cimbala HJ Donahue 《Canadian Metallurgical Quarterly》1998,31(11):969-976
Loading induced fluid flow has recently been proposed as an important biophysical signal in bone mechanotransduction. Fluid flow resulting from activities which load the skeleton such as standing, locomotion, or postural muscle activity are predicted to be dynamic in nature and include a relatively small static component. However, in vitro fluid flow experiments with bone cells to date have been conducted using steady or pulsing flow profiles only. In this study we exposed osteoblast-like hFOB 1.19 cells (immortalized human fetal osteoblasts) to precisely controlled dynamic fluid flow profiles of saline supplemented with 2% fetal bovine serum while monitoring intracellular calcium concentration with the fluorescent dye fura-2. Applied flows included steady flow resulting in a wall shear stress of 2 N m(-2), oscillating flow (+/-2 Nm(-2)), and pulsing flow (0 to 2 N m(-2)). The dynamic flows were applied with sinusoidal profiles of 0.5, 1.0, and 2.0 Hz. We found that oscillating flow was a much less potent stimulator of bone cells than either steady or pulsing flow. Furthermore, a decrease in responsiveness with increasing frequency was observed for the dynamic flows. In both cases a reduction in responsiveness coincides with a reduction in the net fluid transport of the flow profile. Thus. these findings support the hypothesis that the response of bone cells to fluid flow is dependent on chemotransport effects. 相似文献
94.
HJ Deeg W Leisenring R Storb J Nims ME Flowers RP Witherspoon J Sanders KM Sullivan 《Canadian Metallurgical Quarterly》1998,91(10):3637-3645
We reviewed the records and reevaluated 212 patients with aplastic anemia transplanted at the Fred Hutchinson Cancer Research Center (FHCRC) between 1970 and 1993 who survived >/=2 years and who have been followed for up to 26 years. Parameters analyzed included hematopoietic function, chronic graft-versus-host disease (GVHD), skin disease, cataracts, lung disease, skeletal problems, posttransplant malignancy, depression, pregnancy/fatherhood, and the return to work or school, as well as patient self-assessment of physical and psychosocial health, social interactions, memory and concentration, and overall severity of symptoms. Survival probabilities at 20 years were 89% for patients without (n = 125) and 69% for patients with chronic GVHD (n = 86) (the status was uncertain in 1 surviving patient). All patients had normal hematopoietic parameters. Skin problems occurred in 14%, cataracts in 12%, lung disease in 24%, and bone and joint problems in 18% of patients. Eleven patients (12%) developed a solid tumor malignancy and 19% of patients experienced depression. Chronic GVHD was the dominant risk factor for late complications. Seventeen patients died at 2.5 to 20.4 years posttransplant; 13 of these had chronic GVHD and related complications. At 2 years, 83% of patients had returned to school or work; the proportion increased to 90% by 20 years. At least half of the patients preserved or regained the ability to become pregnant or father children. Patients rated their quality of life as excellent and symptoms as minimal or mild. In conclusion, marrow transplantation in patients with aplastic anemia established long-term normal hematopoiesis. No new hematologic disorders occurred. The major cause of morbidity and mortality was chronic GVHD. However, the majority of patients who survived beyond 2 years returned to a fully functional life. 相似文献
95.
FF Cox WJ Morshuis JC Kelder HW Plokker HJ Langemeijer FE Vermeulen 《Canadian Metallurgical Quarterly》1996,10(9):748-753
OBJECTIVES: The aim of this study was to identify factors causing rupture recurrence after surgical repair of postinfarction ventricular septal rupture and to evaluate the indication for reoperation. PATIENTS: Recurrence of rupture was analysed in 25 out of a series of 109 patients who underwent surgical repair for postinfarction ventricular septal rupture between 1980 and 1992 in our institution. RESULTS: The mean interval between initial operation and recurrence was 3.6 days with a median of 2 days. Multivariate logistic regression analysis identified early thrombolysis after infarction (P = 0.0085) as a risk factor for recurrence of the rupture. Rupture recurrence occurred more in the anterior then in the posterior infarction site, although non-significant. Reoperation was indicated in 15 patients, in 13 for postrecurrent cardiac failure. The main determinant of cardiac failure was a large postrecurrent shunt (P = 0.05). The mean interval between initial operation and reoperation was 136 days with a median of 101 days. In 6 patients a combined apical ventricular septal rupture recurrence and anterior ventricular aneurysm was found, in 9 patients the recurrent rupture was proximally located, without concomitant aneurysm formation. Of 15 patients who were reoperated, one died in hospital and three after the in-hospital period. Of 10 patients treated conservatively, one died in hospital and two after the in-hospital period. One residual ventricular septal rupture closed spontaneously. CONCLUSIONS: Rupture recurrence is mainly determined by early thrombolysis. Postrecurrent cardiac failure, as the main indication for reoperation, is dependent on postrecurrent shunt size. 相似文献
96.
97.
PH Kohek B Pakisch H Glanzer G H?ss HJ Mischinger G Wolf P Steindorfer 《Canadian Metallurgical Quarterly》1995,21(6):627-631
Forty-eight patients with non-resectable cancer of the oesophagus and oesophagogastric junction (Group A: Stage I/II, 32; Group B: Stage III/IV, 16) underwent intraluminal Iridium-192 high dose-rate afterloading therapy (5-7 Gy/session, total dose: 5-21 Gy, mean: 12.4 Gy) and external beam irradiation (Karnofsky > or = 80% 50-60 Gy/2 Gy per day; Karnofsky 60-79%: 30 Gy/3 Gy per day). Durable satisfactory palliation (intake of at least semi-solid food) was demonstrated in 96% of patients. The mean survival for group A was 19.1 months and that for group B, 6.9 months, with a 12-month survival rate of 66% (group A) and 0% (group B) (P < 0.001). Local tumour response and complication rate were significantly dose-related with a predicted response rate of 70.5%, and a complication rate of 50% at ERD 129.3 Gy. 相似文献
98.
Standard techniques measuring heart rate (HR) variability do not account for its dependence on the rate and depth of respiration or measure the time relationship between changes in lung volume and HR. We used transfer function analysis to determine the magnitude and time relationship of the HR response to a known change in lung volume in controls and diabetics. This technique demonstrated significant differences between controls and diabetics with varying degrees of autonomic dysfunction. Specifically, reduced supine vagal and increased supine sympathetic HR modulation was found with progression of the autonomic neuropathy. In response to postural change the normal diabetics displayed impaired sympathetic HR modulation. Transfer function analysis yields new insight into the sequence of changes that occur with diabetic autonomic neuropathy and provides an accurate, easily comprehensible measurement of respiratory induced HR variability. 相似文献
99.
U Russ C Balser W Scholz U Albus HJ Lang A Weichert BA Sch?lkens H G?gelein 《Canadian Metallurgical Quarterly》1996,433(1-2):26-34
The inhibitors of the Na+/H+-exchange (NHE1) system Hoe 694 and Hoe 642 possess cardioprotective effects in ischaemia/reperfusion. It is assumed that these effects are due to the prevention of intracellular sodium (Nai) and calcium (Cai) overload. The purpose of the present study was to investigate the effects of Hoe 642 on intracellular pH, Na+ and Ca2+ (pHi, Nai and Cai) in isolated rat ventricular myocytes under anoxic conditions or in cells in which oxidative phosphorylation had been inhibited by 1.5 mmol/l cyanide. In cells which were dually loaded with the fluorescent dyes 2, 7-biscarboxyethyl-5,6-carboxyfluorescein (BCECF) and Fura-2, anoxia caused acidification of the cells (from pHi 7.2 to pHi 6.8) and an increase in Cai from about 50 nmol/l to about 1 micromol/l. The decrease in pHi began before the cells underwent hypoxic (rigor) contracture, whereas Cai only began to rise after rigor shortening had taken place. After reoxygenation, pHi returned to its control value and Cai oscillated and then declined to resting levels. It was during this phase that the cells rounded up (hypercontracture). When 10 micromol/l Hoe 642 was present from the beginning of the experiment, pHi and Cai were not significantly different from control experiments. At reoxygenation, pHi did not recover, but Cai oscillated and returned to its resting level. To monitor Nai, the cells were loaded with the dye SBFI. After adding 1.5 mmol/l cyanide or 100 micromol/l ouabain, Nai increased from the initial 8 mmol/l to approximately 16 mmol/l. Hoe 642 or Hoe 694 (10 micromol/l) did not prevent the increase in Nai. In contrast, the blocker of the persistent Na+ current R56865 (10 micromol/l) attenuated the CN--induced rise in Nai. The substance ethylisopropylamiloride was not used because it augmented considerably the intensity of the 380 nm wavelength of the cell's autofluorescence. In conclusion, the specific NHE1 inhibitor Hoe 642 did not attenuate anoxia-induced Cai overload, nor CN--induced Nai and Cai overload. Hoe 642 prevented the recovery of pHi from anoxic acidification. This low pHi maintained after reoxygenation may be cardioprotective. Other possible mechanisms of NHE1 inhibitors, such as prevention of Ca2+ overload in mitochondria, cannot be ruled out. The increase in Nai during anoxia is possibly due to an influx of Na+ via persistent Na+ channels. 相似文献
100.
HJ Gitelman 《Canadian Metallurgical Quarterly》1994,3(4):471-474
Recent physiologic information concerning the renal response to potassium deprivation has been used to reevaluate potassium wasting in Bartter's syndrome. Experimental patient data support the notion that failure of potassium conservation is due to an imbalance between tubular secretory and reabsorptive processes. Suggestions are presented for the further evaluation of potassium reabsorptive pathways in the distal tubule. 相似文献