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1.
Fourteen Finnish and ten Russian elite male volleyball players were studied for their anthropometric dimensions, maximal isometric trunk extension and flexion, leg extension strength and vertical jumping height. In addition, the height of rise of the body centre of gravity h (C.G.), and the height of the hand and ball were analyzed from a video tape in spike and block jumps taken during actual competition. The two teams were found to differ significantly in the h (C.G.) during a vertical jumping test where a preliminary counter movement was allowed and in the lengths of lower limbs and legs; the Russian volleyball players jumped higher and had longer lower extremities. In actual competition, the hands of the Russian players while performing a spike were on the average ten centimeters higher (p less than .01) than the hand of the Finnish players. No significant differences were found, however, between the teams in the h (C.G.) during spiking. This finding seems to suggest that the Russians have better spike technique.  相似文献   

2.
Patellar tendon is widely used for reconstruction of the anterior cruciate ligament. However, few studies have investigated the tendon's homogeneity, a characteristic often assumed of it in experiments. In this study, the assumption that the patellar tendon is homogeneous was tested by dividing the central half of the tendon into six sections along its length and width and comparing commonly measured biochemical parameters and patterns of gene expression among these sections. No significant differences were found between the sections for any of the studied parameters: water content (p > 0.5), DNA content (p > 0.9), total collagen content (p > 0.8), amount of type I collagen (p > 0.7) or type-III collagen (p > 0.7), or expression of mRNA (p > 0.9). For all parameters, the minimum power value for statistical analyses was greater than 0.80. It was concluded that the central half of the tendon is homogeneous in terms of all of the measured parameters. The results provide important information for the many experiments that sample part of the patellar tendon to infer the characteristics of the whole tendon, e.g., biopsy studies.  相似文献   

3.
Site-directed mutagenesis was used to investigate the loading of iron into rat liver ferritin by ceruloplasmin. Changes were made in the H chain to investigate the role of tyrosines involved in an inherent ferroxidase activity thought to be involved in the self-loading of iron into ferritin. Mutation Y34F affected the rate of iron loading by ceruloplasmin and incorporation of the oxidized iron into the core. Mutation Y29R (making it analogous to the L chain) had no effect on iron oxidation but slightly decreased core formation. A double mutation in the L chain, to open the alpha-helix bundle channel, and R25Y, making the protein more analogous to the H chain, increased the amount of iron incorporated into the core, again suggesting that this Tyr is involved in ligand exchange for core formation. Additional changes in the L chain involving the BC loop suggest that the entire BC loop is involved in the association of ferritin with ceruloplasmin, increasing its ferroxidase activity and the rate of iron loading into ferritin.  相似文献   

4.
This study investigates the influence of patellar thickness in total knee arthroplasty (TKA) with routine patellar resurfacing on the rate of lateral retinacular release. A study group comprised of 121 TKAs using surgical instrumentation allowing a measured resection of the patella was compared with a control group comprised of 100 TKAs using an "eye-ball" technique for patellar resurfacing without particular attention to patellar thickness. A composite without patellar thickness equal to or slightly less than the original patella was attempted in the study group. The average thickness difference of the patella in the study group was -1.58 mm. Lateral retinacular release for patellar maltracking was performed in 12.4% of knees in the study group compared with 55% of knees in the control group. The variation in patellar thickness in this series often led to a residual bone thickness < 15 mm. No clinical problems have been observed to date.  相似文献   

5.
OBJECTIVE: To explore possible effects of aging on the excitability of spinal reflexes. DESIGN: Using a cross-sectional design, the influences of muscle vibration and the Jendrassik maneuver on patellar tendon reflex function were compared between 30 young adults and 15 older adults. SETTING: Motor control research laboratory. SUBJECTS: The young adults were volunteers of college age. The older adults (74.5 +/- 4.14 yr) were volunteers from the local community. All subjects were free of medications and neurological conditions that would affect normal neuromuscular responses. MAIN OUTCOME MEASURES: A force-time curve analysis of the patellar tendon reflex response was used to assess the inhibition and facilitation of spinal reflexes. In the experimental protocol to assess spinal reflex inhibition, 100 Hz vibration was applied to the right quadriceps muscle. In another experimental protocol, spinal reflex facilitation was assessed using the Jendrassik maneuver. To perform the Jendrassik maneuver, subjects were instructed to grasp their hands together and to pull as hard as possible while breathing normally. After a 2-second count, the tendon tap was delivered to the right leg and the subject was instructed to relax. In both experimental protocols, control patellar tendon reflexes were collected. RESULTS: Analysis of variance for reflex peak force revealed a significant 30% reduction in the amount of vibration-induced reflex inhibition with increasing age, and a similar 33% reduction in the amount of Jendrassik maneuver facilitation observed for the older adults as compared with the younger adults. CONCLUSION: These results support the hypothesis that inhibitory and excitatory influences acting on the alpha motoneuron pool are different in young and older adults.  相似文献   

6.
Data from 172 newlywed couples were collected over the first 4 years of marriage to test how behaviors demonstrated during marital interactions moderate associations between depressive symptoms and subsequent life stressors. Depressive symptoms and behaviors coded from problem-solving and social support interactions were analyzed as predictors of nonmarital stressors that were interpersonal and dependent on the participant's actions. Behavioral codes were found to moderate 3 of 16 symptom-to-life event associations for husbands. Husbands' reports of more depressive symptoms predicted greater levels of stress when husbands' positive affect and hard negative affect during problem-solving were relatively infrequent and when wives made frequent displays of positive behaviors during husbands' support topics. These effects remained after controlling for marital satisfaction. For wives, behavioral moderators did not interact with depressive symptoms to predict changes in stress, but marital satisfaction consistently interacted with depressive symptoms to predict future stressors beyond interpersonal behaviors. Specifically, for wives, stress generation was more evident when relationship satisfaction was low than when it was high. Our results, though different for men and women, suggest that relationship functioning can alter associations between depressive symptoms and life stress in the early years of marriage. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

7.
Oligonucleotides coding for linear epitopes of the fimbrial colonization factor antigen I (CFA/I) of enterotoxigenic Escherichia coli (ETEC) were cloned and expressed in a deleted form of the Salmonella muenchen flagellin fliC (H1-d) gene. Four synthetic oligonucleotide pairs coding for regions corresponding to amino acids 1 to 15 (region I), amino acids 11 to 25 (region II), amino acids 32 to 45 (region III) and amino acids 88 to 102 (region IV) were synthesized and cloned in the Salmonella flagellin-coding gene. All four hybrid flagellins were exported to the bacterial surface where they produced flagella, but only three constructs were fully motile. Sera recovered from mice immunized with intraperitoneal injections of purified flagella containing region II (FlaII) or region IV (FlaIV) showed high titres against dissociated solid-phase-bound CFA/I subunits. Hybrid flagellins containing region I (FlaI) or region III (FlaIII) elicited a weak immune response as measured in enzyme-linked immunosorbent assay (ELISA) with dissociated CFA/I subunits. None of the sera prepared with purified hybrid flagella were able to agglutinate or inhibit haemagglutination promoted by CFA/I-positive strains. Moreover, inhibition ELISA tests indicated that antisera directed against region I, II, III or IV cloned in flagellin were not able to recognize surface-exposed regions on the intact CFA/I fimbriae.  相似文献   

8.
Previous studies have shown a strong correlation between depression and smoking, but the mechanism underlying the relationship is not well understood. This study examined whether the prevalence of smoking in schools influences the relationship between smoking and depression symptoms at the individual level. Information on demographics, tobacco use, and depression symptoms for 3,382 students in Grades 7-12 from 126 schools in Ontario, Canada, was obtained from the 2003 Ontario Student Drug Use Survey (E. Adlaf & A. Paglia, 2003). The effect of school-level smoking was strongly negative (coefficient = -1.05, p = .01), suggesting that depression and smoking at the individual level were strongly related in schools with a lower smoking prevalence but that this relationship diminished as the prevalence of smoking increased. Contextual effects may be important to understanding the link between smoking and depression in adolescents. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

9.
We hypothesized that a pattern of decreasing postoperative length of stay (LOS) in the hospital could lead to an increased rate of manipulation after total knee arthroplasty (TKA). The decision to manipulate is based on the patient's ability to perform normal physical activities, which may in large part be dependent on adequate knee flexion (ie, range of motion [ROM]). Decreased exposure to physical therapy (as a result of decreased LOS) may be a contributing factor leading to impaired functional ROM in the 6-week postoperative period. We examined records from 745 patients (2 surgeons) who had a primary TKA from 1993 to 1996. At our institution, development and implementation of clinical pathways resulted in a significant decrease in the average LOS beginning in 1993. The average LOS in 1993 was 6.4 +/- 1.8 days (mean +/- SD) and progressively decreased to 4.4 +/- 1.0 days in 1996 (P < .0001). The rate of manipulation (patients manipulated at 6 weeks/total number of patients receiving TKA) was 6.0% in 1993 and increased to 11.3% (P = .09) in 1994, 13.5% (P = .02) in 1995, and 12.0% (P = .05) in 1996. In the period 1993-1996, patients requiring manipulation consistently had a lower ROM at discharge from the hospital (69.0 +/- 10 degrees, n = 67, P < .0001) compared with patients not requiring manipulation (80.7 +/- 10.6 degrees, n = 542). The relatively low frequency and charge for manipulation may justify the decision to decrease patient exposure to physical therapy through reduction in LOS. As efforts to decrease LOS continue, however, we must aggressively manage patients and provide adequate exposure to inpatient and outpatient physical therapy to ensure optimal ROM results.  相似文献   

10.
11.
Investigated inter- and intraracial differences in understanding during an initial counseling interview. Ss were 16 black and 16 white undergraduates and 4 white and 4 black graduate students in counseling. Excerpts of the interview were utilized in stimulated recall sessions, and 3 trained raters independently evaluated the degree of understanding. Results indicate that race is related to understanding in counseling. Black counselors understood black counselees best, and white counselors understood white counselees best. Overall white counselors understood both white and black counselees better than did black counselors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

12.
The aim of the present study was to assess the effect of normal growth and development on the Peer Assessment Rating index between 12 and 22 years of age. The sample consisted of 49 nonorthodontic subjects (24 male and 25 females) from the Nijmegen Growth Study. The mean age at the first observation was 12.2 +/- 0.7 years and at the second observation 22.1 +/- 0.6 years. The dental casts at these ages were scored with the Peer Assessment Rating index. The influence of the Angle classification and the treatment need on changes over time in the Peer Assessment Rating score were evaluated. The mean changes in the PAR scores over time between cases that have more than 30% improvement to those that have less than 30% improvement were calculated. The results indicate that there were no significant differences between the mean Peer Assessment Rating score at 12 years of age (12.20 +/- 0.91) and at 22 years of age (12.45 +/- 1.28), but there were relevant differences in individual cases. The changes were irrespective of the Angle classification or the treatment need. Changes over time in the weighted Peer Assessment Rating score were mainly correlated to changes in the anterior crossbite and the overjet. This correlation may be influenced, however, by the applied weighting factor for those occlusal traits.  相似文献   

13.
14.
OBJECTIVE: To study the relationship between serum cholesterol level and left ventricular mass for a population of untreated hypertensive patients. DESIGN: A cross-sectional study. PATIENTS: We studied 273 untreated hypertensive patients without associated diseases consecutively referred for evaluation of blood pressure. All patients underwent M-mode echocardiographic assessment of left ventricular mass, office blood pressure measurement and 24 h ambulatory blood pressure monitoring. Fasting plasma glucose and total cholesterol levels were measured on the same day. RESULTS: We found a weak but significant correlation (r = 0.20-0.26, P < 0.01) between serum cholesterol level and left ventricular wall thickness or left ventricular mass irrespective of the mode of indexation used (height, height2.7 and body surface area). In multivariate analysis this relation remained significant after introduction of sex, age, weight, height, blood pressure and blood glucose level. When data for men and women were analysed separately the relationship between left ventricular mass and cholesterol remained significant for men only. CONCLUSION: There is a significant and independent positive relationship between serum cholesterol level and left ventricular mass that could contribute to the prognostic value of left ventricular hypertrophy.  相似文献   

15.
Given the availability of violence risk assessment tools, clinicians are now better able to identify high-risk patients. Once these patients have been identified, clinicians must monitor risk state and intervene when necessary to prevent harm. Clinical practice is dominated by the assumption that increases in psychiatric symptoms elevate risk of imminent violence. This intensive study of patients (N = 132) at high risk for community violence is the first to evaluate prospectively the temporal relation between symptoms and violence. Symptoms were assessed with the Brief Symptom Inventory and threat/control override (TCO) scales. Results indicate that a high-risk patient with increased anger in 1 week is significantly more likely to be involved in serious violence in the following week. This was not true of other symptom constellations (anxiety, depression, TCO) or general psychological distress. The authors found no evidence that increases in the latter symptoms during 1 week provide an independent foundation for expecting violence during the following week. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

16.
The relation between adolescent negative adjustment and differences in parent–child ratings of parents' warmth and negativity was examined with a national sample of 720 families. It was predicted that perceptual differences (PDs) would be linked to more negative adjustment. Adjustment was regressed on PDs, which were calculated as absolute differences between parent and child ratings of parenting. Results showed that PDs were significantly associated with adjustment independent of the level of parenting behavior. Associations differed by gender for PDs over maternal verbal aggression. Some of the most important results were curvilinear effects indicating that both high and low, but not medium, levels of PDs are linked with maladjustment. Finally, differences between younger and older adolescents were found: The linear relationship between PDs over parental negativity and maladjustment disappeared for older adolescents. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

17.
Similar-sized patellar tendon autografts and fresh-frozen allografts were used to reconstruct the anterior cruciate ligament of one knee in 40 female goats. Evaluations of the reconstructions and contralateral controls at the 6-week and 6-month postoperative periods included anterior-posterior translation, mechanical properties determined during tensile failure tests, measurement of cross-sectional area, histology, collagen fibril size and area distribution, and associated articular cartilage degenerative changes. Six months after anterior cruciate ligament reconstruction, the autografts demonstrated a smaller increase in anterior-posterior displacement, values of maximum force to failure two times greater, a significant increase in cross-sectional area, a more rapid loss of large-diameter collagen fibrils, and an increased density and number of small-diameter collagen fibrils compared to the allografts. Clinical significance. More surgeons are allowing their patients to return to running and sports 6 months after anterior cruciate ligament reconstruction. While the structural and material properties of autografts and allografts at time zero are similar, in the goat model during the first 6 months they differ. The allografts demonstrate a greater decrease in their implantation structural properties, a slower rate of biologic incorporation, and the prolonged presence of an inflammatory response. At 6 months the autograft demonstrates a more robust biologic response, improved stability, and increased strength to failure values.  相似文献   

18.
The relationship between the prognosis and age of patients with gastric cancer is controversial. To evaluate whether there is a biological characteristic specific to the age of patients, we examined the clinical characteristics of patients with gastric cancer with special reference to their age. Based on a prospective database, a retrospective study of 419 patients who underwent radical gastrectomy for cure in the past 6 years was conducted. Clinical characteristics including gender, gross appearance of the tumour (Borrmann's classification, tumour location), histopathology (depth of tumour invasion, lymph node status, Lauren's classification and degree of tumour cell differentiation) and TNM tumour stage were analysed in six different age groups (< 39, 40-49, 50-59, 60-69, 70-79, > 80 years). The mean age of the 419 patients was 64.6 years (range from 26-91) and the peak age incidence of gastric cancer (46.3%) was in the 60-69 year old age group. The male: female ratio was 4.6:1 on the whole and male gender predominated at ages > 60. The proportion of diffuse type tumours (68.4%) by Lauren's criteria in the young age group (< 39 yrs) decreased with age (25% in the > 80 years group; P < 0.001). Similarly, the proportion of poorly-differentiated tumours (89.5%) in the young age group (< 39 yrs) decreased with advancing age (P < 0.001). These findings suggest that both diffuse type and poorly-differentiated tumours predominate in younger patients and, without considering the factor of delay in diagnosis, may explain the poorer prognosis demonstrated in younger patients.  相似文献   

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20.
INTRODUCTION: Using the Fourier transform, it is possible to replace each time domain representation of a defibrillatory shock by a unique frequency domain representation in which the shock waveform is defined in terms of a complex number function of frequency and typically described as an amplitude in amperes per hertz (or, closely related, joules per hertz) and an associated frequency-dependent phase angle. METHODS AND RESULTS: The present article describes the conceptual basis of the Fourier transform, sketches a simplified mathematical framework for deriving frequency domain parameters, considers properties crucial to interpreting defibrillatory-type shocks when expressed in the frequency domain, and then presents a series of shock waveforms in the frequency domain. Although not definitive, knowledge of the energy distribution with frequency alone, usually presented in joules per hertz, is shown to yield considerable insight into the probable comparable efficacy of uniphasic/biphasic rectangular, untruncated/truncated uniphasic exponential, and various biphasic "single capacitor" waveforms. CONCLUSION: In general, efficacy in achieving ventricular defibrillation is improved by parameter changes that shift a larger percentage of the delivered energy into a mid-frequency range (very roughly, 40 to 160 Hz). With further study, the frequency domain approach may prove to be a useful tool in the a priori selection of optimal defibrillatory shock waveforms.  相似文献   

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