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991.
992.
Recent studies suggest that local levels of sympathetic nervous activity influence the growth of prostatic tissue. In several epidemiological studies, resting heart rate, an indicator of overall sympathetic activity, was positively associated with all noncardiovascular and cancer death among men. However, no previous analyses have focused on the specific relationship of heart rate to prostate cancer mortality. We studied 22,380 men enrolled in the Chicago Heart Association cohort from 1967-1973, who had heart rate (HR) determined by electrocardiogram. Mean length of follow-up (for mortality) was 19.2 years. We computed age-adjusted rates for prostate cancer death by variable of interest and fitted proportional hazards models to estimate relative risks (RRs) adjusted for potential confounders. In a model controlling for age, body mass index, blood pressure, serum cholesterol, smoking, postload plasma glucose, and years of education, the RR for a 10 beat/min higher HR was 1.26 (95% confidence interval = 1.04-1.51). Age-adjusted RRs across higher quintiles for HR were 1.00, 1.55, 1.85, 2.18, and 2.69 (P trend = 0.006). Survival curves indicated that the elevated risk was not confined to the early years of follow-up. Because little is known about factors that determine risk of prostate cancer death, these results could prove important even if due to an unmeasured etiological factor other than heart rate itself. The results are consistent with the hypothesis that local neurotrophic factors associated with sympathetic activity influence the progression of prostate cancer  相似文献   
993.
This paper presents data on two surveys done in 1989 and 1992 that indicated the attitudes of Singaporeans to sexuality. Both surveys revealed that Singaporeans have sexually conservative attitudes and those who have a lower education, are single, above the age of 40, are Malays/Muslims hold more conservative views.  相似文献   
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996.
BACKGROUND: Activation of platelets and expression of adhesion molecules (e.g. CD62P and CD63) which mediate interactions between platelets and other cells may be important in the pathogenesis of aspirin-sensitive asthma. OBJECTIVE: To determine the expression of CD62P and CD63 on platelets from aspirin-sensitive asthmatic (ASA+), aspirin-tolerant asthmatic (ASA-) and normal subjects and to assess the modulatory effect of aspirin on platelet CD62P and CD63 expression following stimulation with either platelet-activating factor (PAF), arachidonic acid (AA) or collagen (COL). METHODS: Platelet-rich plasma was obtained from 10 ASA+, 10 ASA- and 10 normal control subjects, and expression of CD62P and CD63 was measured by flow cytometry. Platelets were stimulated with PAF (10, 80 nM), AA (0.1, 1 mM) or COL (80, 800 micrograms/mL) with or without aspirin (concentration range 0.4-4 mg/mL). RESULTS: In the absence of aspirin, CD62P expression induced by AA and COL was greater in ASA+ patients compared with control subjects (P < 0.001) while CD62P expression with PAF, AA and COL was reduced in ASA- when compared with ASA+ and control subjects (P < 0.001). CD63 expression with PAF and AA was reduced in both ASA+ and ASA- patients compared with control subjects (P < 0.001). Aspirin inhibited the expression of both CD62P and CD63 after agonist stimulation. Greater inhibition of CD62P expression was observed in ASA+ compared with ASA- patients (P < 0.001) and normal subjects (P < 0.05) while greater inhibition of CD63 expression was observed in normal subjects compared with both ASA+ and ASA- patients (P < 0.05). In ASA+ patients and normal subjects, stimulation with PAF and COL resulted in only one platelet population while in contrast with 1 mM AA two populations were observed. CONCLUSIONS: Enhanced AA- and collagen-induced platelet CD62P expression in ASA+ patients compared with normal subjects and greater inhibition by aspirin of CD62P expression in ASA+ may be relevant to the pathogenesis of this syndrome. Reduced expression of CD62P and CD63 in platelets of ASA- patients following stimulation with PAF and AA may also have implications for the role of platelets and these mediators in the pathogenesis of other forms of asthma.  相似文献   
997.
998.
OBJECTIVE: To study interns' perceptions of their learning during their rotation through a short stay unit (SSU). DESIGN: Case-based, qualitative research study. SETTING: A tertiary care pediatric hospital (The Children's Hospital, Boston, Mass). PARTICIPANTS: Ten interns who had worked in the SSU in the 3 months prior to June 1, 1995, and on a general medical team in the previous 12 months. INTERVENTION: None. MAIN OUTCOME MEASURES: In July 1995, the interns participated in focused, open-ended interviews lasting about 40 to 60 minutes to document their perceptions of their learning during their SSU rotation. The interviews were recorded on audiotape and transcribed prior to analysis. Data were analyzed to discern and categorize themes from the interns' responses. RESULTS: All interns responded favorably to their educational and learning experiences during their rotation through the SSU. Two major themes emerged: (1) the interns' learning, which was affected by the role of the attending physician, the organization and structure of the SSU, and the teaching strategies in the SSU; and (2) the interns' collaborative work with the nursing staff in the SSU, which affected patient care but did not facilitate the interns' learning. CONCLUSION: Clustering in the SSU of patients whose symptoms suggested straightforward diagnoses enhanced interns' educational experiences.  相似文献   
999.
1000.
The expression of VIP precursor products: prepro-VIP(22-79), peptide histidine isoleucine (PHI), peptide histidine valine (PHV), prepro-VIP(111-122), VIP, prepro-VIP(156-170), and prepro-VIP mRNA in the anterior pituitary of estrogen-treated, ovariectomized rats, of ovariectomized controls, and of sham-operated controls was examined. Using radioimmunoassays based on antisera against each of the prepro-VIP sequences, we found that all sequences were expressed and markedly induced by estrogen, except PHI and PHV, which both were undetectable. By immunohistochemistry, it appeared that the number of cells immunoreactive for each of these sequences was increased in the estrogen-treated animals. However, PHI/PHV-immunoreactive cells could not be detected, despite the use of four different PHI antisera with different specificities. Estrogen treatment increased the prepro-VIP mRNA as judged by Northern blotting. In situ hybridization signals for both VIP mRNA and PHI mRNA were observed in few pituitary cells from control animals whereas strong positive signals were observed in a larger number of cells after estrogen treatment. The findings show that estrogen causes activation of the VIP gene expression in anterior pituitary cells, and that the absence of PHI and PHV probably is due to translational or posttranslational events.  相似文献   
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