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991.
992.
Following E. Goffman's (1967) face threat analysis of social interaction, it was hypothesized that the aggressive, playful content of teasing would vary according to social status and relational satisfaction, personality, role as teaser or target, and gender. These 4 hypotheses were tested in analyses of the teasing among fraternity members (Study 1) and romantic couples (Study 2). Consistent with a face threat analysis of teasing, low-status fraternity members and satisfied romantic partners teased in more prosocial ways, defined by reduced face threat and increased redressive action. Some findings indicate that disagreeable individuals teased in less prosocial ways, consistent with studies of bullying. Targets reported more negative emotion than teasers. Although female and male romantic partners teased each other in similar ways, women found being the target of teasing more aversive, consistent with previous speculation.  相似文献   
993.
The results of 31 intracortical dorsal metacarpal stress fractures in 28 horses following unicortical osteostixis were reviewed. The incidence was predominately in the middle third of the lateral aspect of the left metacarpus, and males were affected more commonly. Approximately half of the surgical procedures were performed with the horse in the standing position. The mean times to return to training and racing were 4.25 and 6.9 months respectively. There was no correlation between time taken to return to racing and position of surgery. Complications experienced included lack of suture removal and one case with a seroma.  相似文献   
994.
995.
996.
Local hepatic bloodflow (LHB) and metabolic processes were examined in patients with abdominal diseases during intensive transfusion and infusion therapy attended by incomplete parenteral feeding. A reduction of LHB and disorders of lipid metabolism were observed before surgery. After surgery LHB was still reduced on days 1-3. Cholestatic and cytolytic syndromes developed after the intervention, and a reduction of the protein-synthesizing function of hepatocytes and disorders of the lipid status were observed. By days 7-10 the protein-synthesizing function recovered, as did the enzymatic activity, but no complete recovery of LHB and lipid spectrum were observed.  相似文献   
997.
Four hundred and thirty randomly selected hemodialysis patients, aged 20 years and over, were studied to identify risk factors for vascular access and nonvascular access-related hospitalizations in the immediately preceding 1 year. Risk estimates for hospitalization were assessed using a multinominal logistic analysis model. We measured functional status, utilizing a 14-point Karnofsky scale, and in a separate analysis of covariance, in which Karnofsky score was the outcome, we examined the relationships of age, gender, ethnicity, renal diagnosis, and hospitalization. Individual comparisons were adjusted for multiple comparison bias by Tukey's Honest Difference method. There were a total of 508 hospitalizations of which 322 (63%) lasted > or = 1 week. Two hundred and sixty (60%) patients were hospitalized at least once; 105 (24.4%) for access problems only, 115 (27%) for a nonaccess problem only, and 40 for access and nonaccess-related problems. Access-related problems, accounted for 48% of all hospitalizations. The risk of hemodialysis vascular access morbidity was increased in women (p < 0.028) and white (p < 0.048) hemodialysis patients. Neither diabetic nor elderly hemodialysis patients were at greater risk for access hospitalization than their respective counterparts, though a greater proportion of the access hospitalizations in the elderly (> or = 64 years) lasted > or = 1 week (p < 0.0006). More access-related hospitalizations in blacks (64.5%), lasted for > or = 1 week than in whites (40.6%) (p < 0.001). Hispanics (p < 0.043), whites (p < 0.002), and the older patients (p < 0.054) were at greater risk for nonaccess hospitalization than blacks and younger patients, respectively. Even after adjusting for age, race, and diabetes, each decrease of one unit in the modified Karnofsky score was associated with a 3-4% increased risk for all types of hospitalization (p < 0.001)--poor functional status is associated with increased risk for all hospitalizations. We conclude that the risk for hemodialysis vascular access morbidity is increased in women and white hemodialysis patients. Poor functional status is associated with increased risk for all hospitalizations.  相似文献   
998.
The introduction of several mutations resulted in the generation of improved mutants of the green fluorescent protein (GFP). A strong green (GFPsg25) and blue (BFPsg50) fluorescent protein, gave 50-fold-100-fold brighter fluorescence compared to wild-type GFP and BFP (Tyr66His), respectively, upon expression in mammalian cells. GFPsg25 and BFPsg50 have different excitation and emission maxima. This allows their use as an efficient dual-color tagging system and their independent detection in living cells.  相似文献   
999.
The purpose of this study was to determine the relationship between the ulnar nerve and the cubital tunnel during flexion of the elbow with use of magnetic resonance imaging and measurements of intraneural and extraneural interstitial pressure. Twenty specimens from human cadavera were studied with the elbow in positions of incremental flexion. With use of magnetic resonance imaging, cross-sectional images were made at each of three anatomical regions of the cubital tunnel: the medial epicondyle, deep to the cubital tunnel aponeurosis, and deep to the flexor carpi ulnaris muscle. The cross-sectional areas of the cubital tunnel and the ulnar nerve were calculated and compared for different positions of elbow flexion. Interstitial pressures were measured with use of ultrasonographic imaging to allow a minimally invasive method of placement of the pressure catheter, both within the cubital tunnel and four centimeters proximal to it, at 10-degree increments from 0 to 130 degrees of elbow flexion. As the elbow was moved from full extension to 135 degrees of flexion, the mean cross-sectional area of the three regions of the cubital tunnel decreased by 30, 39, and 41 per cent and the mean area of the ulnar nerve decreased by 33, 50, and 34 per cent. These changes were significant in all three regions of the cubital tunnel (p < 0.05). The greatest changes occurred in the region beneath the aponeurosis of the cubital tunnel with the elbow at 135 degrees of flexion. The mean intraneural pressure within the cubital tunnel was significantly higher than the mean extraneural pressure when the elbow was flexed 90, 100, 110, and 130 degrees (p < 0.05). With the elbow flexed 130 degrees, the mean intraneural pressure was 45 per cent higher than the mean extraneural pressure (p < 0.001). Similarly, with the elbow flexed 120 degrees or more, the mean intraneural pressure four centimeters proximal to the cubital tunnel was significantly higher than the mean extraneural pressure (p < 0.01). Relative to their lowest values, intraneural pressure increased at smaller angles of flexion than did extraneural pressure, both within the cubital tunnel and proximal to it. With the numbers available, we could not detect any significant difference in intraneural pressure measured, either at the level of the cubital tunnel or four centimeters proximal to it, after release of the aponeurotic roof of the cubital tunnel.  相似文献   
1000.
A long-standing question in Quaternary paleontology is whether climate-induced, population-level phenotypic change is a result of large-scale migration or evolution in isolation. To directly measure genetic variation through time, ancient DNA and morphologic variation was measured over 2,400 years in a Holocene sequence of pocket gophers (Thomomys talpoides) from Lamar Cave, Yellowstone National Park, Wyoming. Ancient specimens and modern samples collected near Lamar Cave share mitochondrial cytochrome b sequences that are absent from adjacent localities, suggesting that the population was isolated for the entire period. In contrast, diastemal length, a morphologic character correlated with body size and nutritional level, changed predictably in response to climatic change. Our results demonstrate that small mammal populations can experience the long-term isolation assumed by many theoretical models of microevolutionary change.  相似文献   
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