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Hahn  PF; Stark  DD; Vici  LG; Ferrucci  JT  Jr 《Radiology》1986,159(2):379-382
Proper management of duodenal hematoma requires that an accurate diagnosis be made using noninvasive radiological methods. Conventional imaging may be nonspecific if there is no history of trauma or coagulopathy. Two cases of duodenal hematoma that were imaged by magnetic resonance (MR) and computed tomography (CT) are described. In both cases the hematoma had a well-defined concentric ring configuration on MR images, a finding which helped establish the diagnosis. MR imaging may provide tissue-specific characterization of duodenal hematomas.  相似文献   
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(-),(+)黄皮酰胺对鼠脑内 NMDA- 受体的影响   总被引:7,自引:1,他引:7  
段文贞  张均田 《药学学报》1997,32(4):259-263
用[3H]MK-801放射配体竟争结合法测定了(-),(+)黄皮酰胺对大鼠前脑,海马,皮层等部位突触膜的NMDA-R的作用,以探讨其促智机制。同时用饱和实验分析po给药10d后,小鼠脑内该受体密度的变化。结果表明:(-),(+)黄皮酰胺对脑内各部位的NMDA受体均无特异亲和力。但(-)黄皮酰胺在体给药10d后能使小鼠脑内NMDA受体密度显著增高,并呈一定的量效关系。提示黄皮酰胺的药理作用有光学选择性;(-)黄皮酰胺增加脑内NMDA受体密度为其促智作用提供了重要理论依据。  相似文献   
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BACKGROUND: Controversy remains on the relationship between high-density lipoprotein cholesterol (HDL-C) and atherosclerotic cerebrovascular disease. METHODS: Over 5000 women living in the area of Naples, Southern Italy, were recruited for a prospective study on the etiology of cardiovascular disease in the female population (the 'Progetto ATENA' study). A sample of 310 participants underwent high-resolution B-mode ultrasound examination and the intima-media thickness and diameters of common carotid artery were measured. In addition to routine biochemical tests, these women also had oxidation markers determined. RESULTS: Women in the upper HDL-C quartile (HDL-C>1.89 mmol/L) had significantly lower body mass index and waist-to-hip ratio values, and triglycerides concentrations when compared with women in the first three quartiles. A linear negative association was found between HDL-C and carotid intima-media thickness (1.07+/-0.16 mm for the IV quartile versus 1.10+/-0.20 mm for the III quartile, 1.15+/-0.26 mm for the II quartile and 1.19+/-0.23 mm for the I quartile; P<0.01 by ANOVA). No difference was found between groups with regard to carotid diameters and oxidation markers. After adjustment for other cardiovascular risk factors, women in the highest quartile of HDL-C had a decreased risk of carotid intima-media thickening (OR 0.42, 95%CI 0.23-0.94). CONCLUSIONS: In asymptomatic middle-aged women, HDL-C levels were independently and negatively associated with preclinical atherosclerotic changes of the carotid artery wall.  相似文献   
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High blood pressure (BP) is one of the crucial determinants of the metabolic syndrome (MS). The extent to which MS, diagnosed according to the criteria of the International Federation of Diabetes, impacts on cardiovascular organ damage, independently of BP, is debated. Three hundred and forty hypertensive patients and 100 normotensive controls underwent the following procedures: (1) physical examination and resting BP measurements, (2) 24 h ambulatory BP monitoring, (3) laboratory routine examination, (4) echocardiography, (5) carotid ultrasonography and (6) ankle-brachial BP index. The syndrome was found in 104 of the 340 hypertensive patients (30.6). In comparison to those without MS, those with MS had significantly higher prevalence of left ventricular (LV) hypertrophy by mass/height(2.7) criteria (46 vs 42%, P<0.01) but not by LV mass/body surface criteria (30 vs 31%); the ratio between early-to-late peak velocities of the LV filling waves (E/A) was higher (E/A=0.99+/-0.14 vs 0.89+/-0.15, P<0.01) and left atrium was larger (3.8+/-0.3 vs 3.5+/-0.5 cm, P<0.01). Both hypertensive groups had significantly greater LVM and carotid intima-media thickness than normotensives, without between-group-difference. In this hypertension outpatient clinic almost one-third hypertensive patients have MS. They show a deterioration in structure and function of the heart in comparison to hypertensive patients without MS, but no difference was detected in the carotid and peripheral arterial circulation.  相似文献   
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Interest in estimating HIV-1 incidence using specimens obtained as part of cross-sectional surveys has led to the development of new methods to detect recent HIV-1 infection through the testing of a single anti-HIV-positive specimen. These assays are based on quantitative and qualitative differences in anti-HIV-1 antibodies between recent and long-standing infections. An ongoing vaccine preparedness study enrolled female sex workers in the Dominican Republic. Specimens from women found to be HIV positive at baseline were tested for recent HIV-1 infection using the detuned assay, avidity index, and BED-CEIA assay. An unweighted kappa statistic in pairwise comparisons was used to estimate the correlation of recent HIV-1 infection detection by the three methods. Nineteen (3.9%) of 482 women were positive for HIV-1 infection. The incidence of HIV infection was 1.4% [95% confidence interval (CI): 0.2, 5.3], 0.9%(95% CI: 0.1, 4.4), and 1.0%(95% CI: 0.1, 4.4) using detuned assay, avidity index, and BED-CEIA techniques, respectively. The overall agreement between both detuned assay and avidity index and detuned assay and BED-CEIA was 94%(kappa = 0.8, 95% CI; 0.3, 1.0). The correlation was highest between BED-CEIA and avidity index methods (100%; kappa = 1.0). All three methods performed similarly in detecting recent HIV-1 infection in this region dominated by clade B HIV-1 infection. Although incidence estimates were slightly higher using the detuned assay method, they were not significantly different. These assays may be of value in both clinical research and practice. The utility of individual assays for recent infection detection will depend upon operating characteristics, HIV-1 subtype limitations, and selection of appropriate assay cutoff values.  相似文献   
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Return to post-test counselling is essential for optimal individual and public health impact of voluntary counselling and testing (VCT) services. Our study assessed factors associated with return to post-test counselling among 309 out-of-treatment injecting drug users who underwent VCT as part of a cross-sectional survey in Bac Ninh, Vietnam during August and September 2003. The overall return rate to post-test counselling was 54% (n=167). While participants in the rural study district were significantly less likely (chi2=5.8; p<0.05) to return compared with participants in the town centre (42.7 versus 58.1%), return rates did not significantly vary by age, perception of personal HIV risk, HIV serostatus diagnosed by the study, counsellor, history of HIV testing or prior knowledge of HIV status. In a multivariate analysis, higher return rate was associated with residence in Bac Ninh town centre (adjusted OR=1.9; CI=1.1-3.1). Of HIV-positive participants (n=131), 45% (n=59) did not return to collect test results. In view of the findings it is crucial to address risk perception and benefits of collecting test results during pre-test counselling sessions in order to maximize the desired impact of community-based VCT services targeting IDUs in Vietnam.  相似文献   
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