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Birth placement and childhood disadvantage   总被引:1,自引:0,他引:1  
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PURPOSE: To examine the perceptions of faculty role models to learn whether their perceptions of role models' behaviors are congruent with those of their students. METHOD: In 1996 a survey was mailed to 210 student-identified faculty role models at the University of Washington School of Medicine and the University of North Carolina at Chapel Hill School of Medicine. The nominees were asked to rate to what extent each of 32 student-identified role model characteristics was representative of their behavior. They were then asked to rank order the characteristics they felt were most important to model for students. The role models were also asked to rate how much influence they perceived themselves to have on their students' specialty choices. A final, open-ended question inquired about the single characteristics they modeled to students that most influenced the students' specialty choices. The role models' specialties were grouped as either primary care (PC) or non-primary care (NPC). Data were analyzed with several statistical methods. RESULTS: Of the 210 mailed surveys, a total of 177 were returned, for a response rate of 84%. The role models perceived their behaviors much like their students did; the role models' self-ratings were generally high for all of the student-defined characteristics. Although clinical reasoning was considered the most important characteristic to model for students, the role models also believed that enthusiasm and love for their work were the characteristics that most influenced their students' specialty choices. Few differences were found between the PC and the NPC role models. CONCLUSION: The role models in this study agreed with their students about what is important to model. They did not intentionally try to recruit students to join their specialties but felt that demonstrating enthusiasm and a sincere love for what they did has a strong influence toward this end.  相似文献   
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In 1993 a number of cases of unexplained adult respiratory syndrome occurred in the southwestern United States. The illness was characterized by a prodrome of fever, myalgia, and other symptoms followed by the rapid onset of a capillary leak syndrome with hemoconcentration, thrombocytopenia, and pulmonary edema. Viral RNA sequences in the lungs identified a new member of the hantavirus genus, Sin Nombre virus (SNV), unique to North America. Pulmonary endothelial cells were heavily infected but were not necrotic. We speculated that this capillary leak syndrome was initiated by immune responses to the SNV-infected pulmonary endothelial cells. We isolated a CD8+ cytotoxic T lymphocyte (CTL) clone directly from the blood of a patient with the acute hantavirus pulmonary syndrome (HPS) which recognizes a SNV specific epitope on the virus nucleocapsid protein (aa 234-242) that is restricted by HLA C7 and produces IFN gamma but not IL-4. We identified a second CD8+ CTL epitope located within another site aa 131-139 on the nucleocapsid protein, which is HLA B35 restricted, and a CD4+ CTL epitope located on a third site on nucleocapsid protein aa 372-380 using lymphocytes obtained during HPS from another patient that were stimulated in vitro. Hantavirus specific CD8+ and CD4+ CTL may contribute to the immunopathology and capillary leak syndrome observed in the HPS.  相似文献   
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Two experiments were conducted to study the effect of feeding raw or treated common vetch seeds (V) on BW, feed intake (FI), egg production (EP), feed conversion (FC), egg weight (EW), shell thickness (ST), yolk color score (YC), and Haugh unit score (HU) of Single Comb White Leghorn hens for 56 d. In Experiment 1, diets contained 0, 7.5, 15, and 22.5% raw V. Compared with the control, the 22.5% V diet decreased (P < .05) BW, FI, and EP. In Experiment 2, intact or ground (G) V were either soaked (S) in water (1:5) for 24 h or autoclaved (A) at 103.5 x 10(3) Pa for 8 h, and then dried (D) at 55 C for 24 h. Eight diets were used, a corn soybean (control) and seven others, each containing 25% V, previously subjected to the forementioned treatments as follows: untreated V (UV), SDV, GSDV, ADV, GADV, SADV, and GSADV. Compared with the control, the UV diet decreased (P < .05) FI (75 vs 98 g) and EP (47.3 vs 88.7%), increased FC (1.99 vs 1.4 kg feed per dozen eggs), and induced BW loss (-63 vs 49 g). Soaking intact V improved (P < .05) FI (85 g) and EP (69%). Remaining treatments resulted in further improvement. Hens fed all V diets produced eggs with HU score 13 points better than that of the control (P < .05). In both experiments, EW, YC, and ST were not different among treatments. Results indicated that autoclaved V at 25% level was not detrimental to layers' performance.  相似文献   
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The ethanol withdrawal syndrome includes anxiety as a prominent symptom. Because the extent that specific regions of brain are critical to the generation of this emotional state is unknown, Fos-like immunoreactivity (Fos-LI) was used to associate specific regions of the rat brain with the anxiety component of the ethanol withdrawal syndrome exacerbated by an air puff challenge in rats. Chronic ethanol liquid diet was administered intragastrically for 4 days or by having the rats consume the diet for 14 days. During withdrawal from either treatment protocol, Fos-LI was induced most prominently in forebrain areas, although the midbrain and hindbrain were also represented. Included in these Fos-LI positive regions were many cortical regions, septum, accumbens, claustrum, amygdala, paraventricular nucleus of the thalamus and hypothalamus, hippocampus, locus coeruleus, and central gray. Fos-LI expression differed mostly in intensity between the two treatment and withdrawal protocols, with the gastric protocol producing the greatest Fos-LI induction in most brain regions. The threshold for air puff-induced ultrasonic vocalizations was decreased, and the number of vocalizations was increased and the period of vocalization was extended. These behavioral data indicate that aversively motivated responding in rats during ethanol withdrawal can be readily quantified with the ultrasonic vocalizations test without precipitating convulsive activity. Furthermore, a comparison of the effects of the air puff challenge versus withdrawal on Fos-LI indicated that the behavioral state induced in these two situations share functional neuroanatomical features. Some regions--such as the accumbens core, medial septum, subregions of the amygdala, hippocampus, substantia nigra, and cerebellum--exhibited little Fos-LI during withdrawal and also did not exhibit strong increases after the addition of the air puff challenge. However, other regions-such as the cerebral cortex (medial prefrontal, frontal, cingulate and ventrolateral orbital, claustrum, and tenia tecta), hypothalamus, and locus ceoruleus- exhibited Fos-LI at levels higher than that seen after either the ethanol withdrawal or puff challenge alone. These overlapping patterns of Fos-LI in specific regions of the brain, activated by both ethanol withdrawal and an anxiety provoking behavioral challenge, suggest that specific neuroanatomical sites in brain are associated with the symptom of anxiety observed during the "ethanol withdrawal syndrome."  相似文献   
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PURPOSE: To verify the acclaimed accuracy of ultrasound (US) combined with US-guided fine-needle aspiration biopsy (FNAB) in the detection of lymph node metastasis in the neck and to evaluate the interobserver variability. MATERIALS AND METHODS: In a prospective, multicenter study of 185 patients with head and neck squamous cell carcinoma, US (n=238 neck sides) with US-guided FNAB (n=178 neck sides) was used for evaluation of the lymph node status of the neck. Findings were correlated with those of histopathologic examination in 238 neck sides. RESULTS: US with US-guided FNAB had a sensitivity of 77% and a specificity of 100%. Nineteen of 178 aspirations were nondiagnostic. There were no significant differences between the four participating hospitals or the individual sonologists (P>.05). CONCLUSION: Sensitivity of US with US-guided FNAB was slightly lower compared with previous reports. Specificity was similar to previous reports. Interobserver variability appeared to be low. The validity of US with US-guided FNAB is high and warrants widespread use of the procedure for evaluation of the neck.  相似文献   
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