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排序方式: 共有4432条查询结果,搜索用时 15 毫秒
1.
Brenda M Sandmaier Storb Rainer Yanfang Liu Erlinda B Santos Eileen Bryant Friedrich G Schuening H Joachim Deeg Kristy Seidel Theodore Graham 《Transplant immunology》1996,4(4):271-274
920 cGy total body irradiation (TBI) is adequate for consistently successful engraftment of marrow from dog leukocyte antigen (DLA)-identical littermates; however, the dose is inadequate to ensure a marrow graft from DLA-nonidentical unrelated donors. Such mismatched grafts are successful only after 1800 cGy, given in three fractions. While anti-T-cell reagents enhance engraftment of DLA-identical littermate marrow after 920 cGy, they fail to be effective in the DLA-nonidentical setting. However, a monoclonal antibody (mAb) to CD44, S5, was found to be very effective in enhancing engraftment of DLA-nonidentical marrow. The current study asked whether mAb S5 was also effective in the setting of DLA-identical littermate transplants. To this purpose, the TBI dose was lowered to 450 cGy, a dose after which 70% of such grafts failed. Four dogs were treated with antibody S5, 0.2 mg/kg on days −7 though −2 (per previously published protocol), given 450 cGy TBI followed by marrow grafts from their DLA-identical littermates. All four dogs rejected their grafts; two of these died from marrow aplasia, and two survived with endogenous marrow recovery. This result was not statistically significantly different from that in 17, historical (n = 5) and concurrent (n = 12), control dogs where 11 of 17 animals rejected. Even if ten experimental animals were transplanted and all six remaining dogs engrafted, the results still would not have been significantly different from control. This result is in contrast to the successful engraftment promoted by pretreatment with antibody S5 of DLA-nonidentical unrelated dogs, consistent with the notion that different host cells are involved in graft rejection in the two disparate histocompatibility settings. 相似文献
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Although psychological debriefing (PD) represents the most common form of early intervention for recently traumatized people, there is little evidence supporting its continued use with individuals who experience severe trauma. This review identifies the core issues in early intervention that need to be addressed in resolving the debate over PD. It critiques the available evidence for PD and the early provision of cognitive-behavioral therapy (CBT). Based on available evidence, we propose that psychological first aid is an appropriate initial intervention, but that it does not serve a therapeutic or preventive function. When feasible, initial screening is required so that preventive interventions can be used for those individuals who may have difficulty recovering on their own. Evidence-based CBT approaches are indicated for people who are at risk of developing posttraumatic psychopathology. Guidelines for managing acutely traumatized people are suggested and standards are proposed to direct future research that may advance our understanding of the role of early intervention in facilitating adaptation to trauma. 相似文献
4.
Effect of calcium antagonist drugs on calcium currents in mammalian skeletal muscle fibers 总被引:5,自引:0,他引:5
K B Walsh S H Bryant A Schwartz 《The Journal of pharmacology and experimental therapeutics》1986,236(2):403-407
The calcium channel-inhibiting drugs diltiazem, verapamil and nitrendipine represent three general classes of organic calcium antagonists. In the present study, the effect of these drugs on calcium currents (ICa++) in rabbit sternomastoid muscle fibers was examined. ICa++ were recorded at room temperature using a vaseline gap voltage clamp. ICa++ measured had similar kinetics to those reported in rat skeletal muscle, were partially blocked by 0.5 mM CdCI2 and could be reduced by substitution of Mg++ for Ca++. Diltiazem reversibly blocked ICa++ in a concentration-dependent manner with the 50% inhibitory concentration (IC50) being 63 microM. Verapamil was slightly more potent with approximately 50% block of ICa++ occurring at 10 microM. In contrast, nitrendipine at concentrations from 1 to 10 microM had no blocking action on ICa++, even after 20 min of exposure. Thus, although Ca++ channels in mammalian skeletal muscle fibers are readily blocked by cadmium, diltiazem and verapamil, these channels appear to be insensitive to the dihydropyridine compound nitrendipine. 相似文献
5.
Kellie D Bryant 《The ABNF journal》2006,17(4):133-136
Adolescent pregnancy is a social issue that severely jeopardizes the quality of life for young parents and their children. It is estimated that if fertility rates remain unchanged, the United States will see a 26% increase in the number of adolescent pregnancies and births due to an increase in the adolescent population (Henshaw, 1996). With a disproportional rate of Black adolescents becoming pregnant, there is a need to examine factors related to the high adolescent pregnancy rate among the Black community. Black adolescent mothers and their children face additional adverse psychosocial effects due to healthcare disparities, a higher incidence of health problems, and an increase risk of financial hardship (Hogan, Astone, & Kitagawa, 1985; J. V. Horn, 1998; Morgan, Chapar, & Fisher, 1995). Although the teenage pregnancy rate has declined, it is important for practitioners to continue to implement interventions that promote abstinence and increase contraceptive use among sexually active adolescents. 相似文献
6.
R H Curry P R Yarnold F B Bryant G J Martin R L Hughes 《Evaluation & the health professions》1988,11(1):113-129
The selection and subsequent performance of 212 internal medicine residents was examined by factor analysis and path analysis. A three-factor solution accounted for most of the variance among the nine selection variables. These three factors, labeled Board Scores, Faculty Evaluations, and Academic Distinction, were then combined with in-training residency performance evaluations and composite scores on the ABIM certifying examination to produce a comprehensive path model of house staff selection and performance. The Academic Distinction factor emerged as the strongest predictor of residency performance,; the Faculty Evaluations factor was also a significant component of the model. Standardized test scores correlated poorly with clinical performance. The data suggest that increased attention to the content of letters of reference could substantially improve their predictive validity. Other means of reporting subjective evaluations may also be needed to increase the stature of non-cognitive attributes in house staff selection decisions. 相似文献
7.
This study investigated preferential encoding of threat material in subjects with posttraumatic stress disorder (PTSD) with a modified dot-probe paradigm. This paradigm indexes attentional bias by measuring response latency to name neutral target words that are presented adjacent to or distant from threat words. Motor vehicle accident survivors with PTSD (n = 15), subclinical PTSD (n = 15), and low anxiety (n = 15) were required to name target words that were presented either adjacent to or distant from strong threat, mild threat, positive, and neutral words. PTSD subjects named targets faster when they were in close proximity to mild threat words. Results suggested that PTSD subjects' attention was drawn to the mild threat stimuli and are discussed in the context of network models of PTSD. 相似文献
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The authors explore linkages between family and work roles. They examine patterns of apparent economic strategies of spouses working at a southern university located in a rural area. Their research focuses on spousal economic behavior and specifically addresses the effects of spouses' dual employment on the job status of women, differences between spouses in the timing of education and 1st hire at the university, status consistencies in husband and wife employment levels, and sexual discrimination in job levels and income of coemployed spouses. The study uses data extracted from a personnel data set. Cases from a computerized file were identified in 1980-1981, analyzed with 1981-1982 data, and compared with total work force data for 1982-1983. Slightly more than 1/2, or 123 identified cases, were analyzed. Some study findings follow. 1) Marriage to a coemployed spouse is associated with high occupational levels for female employees. 2) It is the husband's career that generally dictates the entry of a couple into the university's internal labor market. 3) There seems to be a strain toward consistency in the status levels of married pairs. 4) Collaborative strategies are being used to secure economic advances for the family unit. Major efforts regarding education and job selection are directed toward advancing the husband's career preference. However, some exceptions suggest that the pattern is flexible and that economic factors will take precedence over stereotyped sex roles when family needs come into consideration. 5) There is employment discrimination by sex at all levels of the internal labor market being studied. Status and income differentials still exist between males and females. Males in the same occupational statuses are paid more than their female counterparts. Females are concentrated at the lower levels of occupational ranks, males toward the top. Although this study is preliminary, it provides partial support for previous research on coemployed spouses' patterns of educational and occupational attainment, and the persistence of sex discrimination in earnings and occupational prestige. 相似文献
10.
Blood platelet uptake of serotonin in episodic aggression 总被引:2,自引:0,他引:2
C S Brown T A Kent S G Bryant R M Gevedon J L Campbell A R Felthous E S Barratt R M Rose 《Psychiatry research》1989,27(1):5-12
Blood platelet uptake of 3H-serotonin (5HT uptake), a potential marker of serotonergic function, was determined in male outpatients with episodic aggression (n = 15) and in age- and sex-matched nonaggressive controls (n = 15). Correlations with rating scales of "impulsivity" (Barratt Impulsivity Scale, 10th revision) and "anger" (Spielberger Anger Expression Scale) were performed. Mean 5HT uptake was 18% lower in patients with episodic aggression. A significant negative correlation between % difference in platelet 5HT uptake and impulsivity score was observed, but the correlation between 5HT uptake and anger was not significant. These results support the hypothesis of disturbed serotonergic function in aggression and suggest that the primary relationship is in the "control" of aggression. The blood platelet may be useful in identifying impulsive subtypes. 相似文献