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101.
van Uden CJ Nieman FH Voss GB Wesseling G Winkens RA Crebolder HF 《BMC health services research》2005,5(1):27
Background
In recent years, Dutch general practitioner (GP) out-of-hours service has been reorganised into large-scale GP cooperatives. Until now little is known about GPs' experiences with working at these cooperatives for out-of-hours care. The purpose of this study is to gain insight into GPs' satisfaction with working at GP cooperatives for out-of-hours care in separated and integrated cooperatives. 相似文献102.
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104.
Pfaff JJ Bernert RA Hollar DL Witte TK Merrill KA Pettit JW Almeida OP Joiner TE 《Psychiatry research》2006,144(2-3):217-219
We examined the relationship between season of birth and depressive and suicidal symptoms among 859 elderly outpatients. Date and country of birth were recorded for each participant. Those in utero during the Northern or Southern Hemisphere flu peak were expected to show the highest depressive and suicidal symptoms. Hypotheses were partially supported. 相似文献
105.
Braun JM Kalkbrenner AE Calafat AM Bernert JT Ye X Silva MJ Barr DB Sathyanarayana S Lanphear BP 《Environmental health perspectives》2011,119(1):131-137
Background
Prenatal bisphenol A (BPA) exposure may be associated with developmental toxicity, but few studies have examined the variability and predictors of urinary BPA concentrations during pregnancy.Objective
Our goal was to estimate the variability and predictors of serial urinary BPA concentrations taken during pregnancy.Methods
We measured BPA concentrations during pregnancy and at birth in three spot urine samples from 389 women. We calculated the intraclass correlation coefficient (ICC) to assess BPA variability and estimated associations between log10-transformed urinary BPA concentrations and demographic, occupational, dietary, and environmental factors, using mixed models.Results
Geometric mean (GM) creatinine-standardized concentrations (micrograms per gram) were 1.7 (16 weeks), 2.0 (26 weeks), and 2.0 (birth). Creatinine-standardized BPA concentrations exhibited low reproducibility (ICC = 0.11). By occupation, cashiers had the highest BPA concentrations (GM: 2.8 μg/g). Consuming canned vegetables at least once a day was associated with higher BPA concentrations (GM = 2.3 μg/g) compared with those consuming no canned vegetables (GM = 1.6 μg/g). BPA concentrations did not vary by consumption of fresh fruits and vegetables, canned fruit, or store-bought fresh and frozen fish. Urinary high-molecular-weight phthalate and serum tobacco smoke metabolite concentrations were positively associated with BPA concentrations.Conclusions
These results suggest numerous sources of BPA exposure during pregnancy. Etiological studies may need to measure urinary BPA concentrations more than once during pregnancy and adjust for phthalates and tobacco smoke exposures. 相似文献106.
CT模拟结肠镜在结肠病灶诊断中的应用 总被引:2,自引:0,他引:2
结肠癌是常见的消化道肿瘤,上海等地区的发病率有明显增高的趋势。在发达国家,结肠癌占肿瘤死亡率第二位,且与大肠腺瘤关系密切。如能早期发现有恶变先兆的息肉并切除之,可以预防结肠癌发生。目前,对结肠癌发病高危人群并未作大规模普查,部分由于患者缺乏早期主诉,或是由于现有普查手段不够有效。大便隐血试验只能发现30%~40%结肠肿瘤,乙状结肠镜不能进入近端结肠,并有10%~15%乙状结肠肿瘤漏诊。钡剂灌肠和结肠镜能检查全结肠,但有10%~15%患者行结肠镜检查失败,并且结肠镜可能使10%~20%病灶遗漏,尚… 相似文献
107.
108.
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
109.
(-),(+)黄皮酰胺对鼠脑内 NMDA- 受体的影响 总被引:7,自引:1,他引:7
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
110.