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由于双层类脂膜(bilayer lipid membranes,BLMs)是生物膜极好的实验模型,因此在生物传感器的研制领域显示出广泛的应用前景。在对生物膜结构进化的简短总结后,介绍了有固态基底支撑的BLMs(supported bilayer lipid membranes,S-BLMs)的研究发展状况,并综述了其在生物传感器中的应用研究进展。  相似文献   
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何承  李瑞峰  谢海涛 《医学争鸣》2005,26(14):1332-1332
1临床资料1999-08/2004-08我科采用延迟小骨窗开颅手术治疗硬膜外血肿96(男75,女21)例,年龄13~18(平均35)岁.受伤原因车祸72例,坠落伤11例,打击伤13例.均于伤后72 h内就诊并经头颅CT确诊,表现头痛96例,呕吐21例,一侧肢体无力32例,偏身麻木23例,癫痫发作1例,原发昏迷92例,59例≤30 min,33例为30~120 min,头痛进行性加重36例.就诊时GCS记分10~12分15例,13~15分81例,运动性失语2例,混合性失语3例.CT示血肿位于额顶叶12例,额叶32例,颞叶5例,顶枕叶8例,颞顶后39例(1例合并对侧脑内血肿,5例合并额颞叶脑挫裂伤).血肿量30~80mL.入院后3~15 d内先给予脱水剂、激素、止血剂、抗生素、脑活性药物、镇痛剂等对症处理保守治疗.  相似文献   
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Dietary carotenoids are associated with a reduced risk of chronic diseases. Raw food diets are predominantly plant-based diets that are practised with the intention of preventing chronic diseases by virtue of their high content of beneficial nutritive substances such as carotenoids. However, the benefit of a long-term adherence to these diets is controversial since little is known about their adequacy. Therefore, we investigated vitamin A and carotenoid status and related food sources in raw food diet adherents in Germany. Dietary vitamin A, carotenoid intake, plasma retinol and plasma carotenoids were determined in 198 (ninety-two male and 106 female) strict raw food diet adherents in a cross-sectional study. Raw food diet adherents consumed on average 95 weight% of their total food intake as raw food (approximately 1800 g/d), mainly fruits. Raw food diet adherents had an intake of 1301 retinol activity equivalents/d and 16.7 mg/d carotenoids. Plasma vitamin A status was normal in 82% of the subjects (> or = 1.05 micromol/l) and 63% had beta-carotene concentrations associated with chronic disease prevention (> or = 0.88 micromol/l). In 77% of subjects the lycopene status was below the reference values for average healthy populations (< 0.45 micromol/l). Fat contained in fruits, vegetables and nuts and oil consumption was a significant dietary determinant of plasma carotenoid concentrations (beta-carotene r 0.284; P < 0.05; lycopene r 0.168; P = 0.024). Long-term raw food diet adherents showed normal vitamin A status and achieve favourable plasma beta-carotene concentrations as recommended for chronic disease prevention, but showed low plasma lycopene levels. Plasma carotenoids in raw food adherents are predicted mainly by fat intake.  相似文献   
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Currently the hematoxylin and eosin staining procedure is the most popular among Mohs surgeons for histology. However, safranin O, a cheaper and relatively safer stain which is predominantly used for plant histology, should be considered as it offers similar or improved accuracy in the diagnosis of frozen sections of basal and squamous cell carcinomas.  相似文献   
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The arterial grafts currently in use are classified into five basic categories; 10 different commercially available prostheses were chosen to represent these categories. The Vascutek and Bionit are made from knitted Dacron and have medium porosity, requiring preclotting by the surgeon. The DeBakey Soft Woven and Plasma TFE grafts are made from woven Dacron and have low porosity, not requiring preclotting under most circumstances. Also studied were woven and knitted grafts with leakage resistance referred to as impervious Dacron grafts: the Vascutek Gelseal, the Bard Albumin Coated DeBakey Vasculour II, the Microvel with Hemashield, and the albumin saturated, autoclaved DeBakey Soft Woven graft. Gore-Tex and Impra are expanded polytetrafluoroethylene grafts which do not require preclotting. For each type, five grafts 6 cm long and 8 mm in diameter were implanted in the descending thoracic aorta of healthy adult dogs for 16 weeks. The physical characteristics, biocompatibility, and healing patterns varied according to the structure and treatment of the grafts. Pretreatment with biomaterials during manufacture is quite effective in preventing transinterstices blood loss during implantation, but results in altered physical qualities, increased thrombogenicity and delayed healing in comparison to the effects of preclotting with autogenous blood at the time of implantation.  相似文献   
100.

Background

In the Netherlands, 30% of subfertile women are overweight or obese, and at present there is no agreement on fertility care for them. Data from observational and small intervention studies suggest that reduction of weight will increase the chances of conception, decrease pregnancy complications and improve perinatal outcome, but this has not been confirmed in randomised controlled trials. This study will assess the cost and effects of a six-months structured lifestyle program aiming at weight reduction followed by conventional fertility care (intervention group) as compared to conventional fertility care only (control group) in overweight and obese subfertile women. We hypothesize that the intervention will decrease the need for fertility treatment, diminish overweight-related pregnancy complications, and will improve perinatal outcome.

Methods/Design

Multicenter randomised controlled trial in subfertile women (age 18-39 year) with a body mass index between 29 and 40 kg/m2. Exclusion criteria are azoospermia, use of donor semen, severe endometriosis, premature ovarian failure, endocrinopathies or pre-existent hypertensive disorders. In the intervention group the aim is a weight loss of at least 5% to10% in a six-month period, to be achieved by the combination of a diet, increase of physical activity and behavioural modification. After six months, in case no conception has been achieved, these patients will start fertility treatment according to the Dutch fertility guidelines. In the control group treatment will be started according to Dutch fertility guidelines, independently of the patient's weight.

Outcome measures and analysis

The primary outcome measure is a healthy singleton born after at least 37 weeks of gestation after vaginal delivery. Secondary outcome parameters including pregnancy outcome and complications, percentage of women needing fertility treatment, clinical and ongoing pregnancy rates, body weight, quality of life and costs. Data will be analysed according to the intention to treat principle, and cost-effectiveness analysis will be performed to compare the costs and health effects in the intervention and control group.

Discussion

The trial will provide evidence for costs and effects of a lifestyle intervention aiming at weight reduction in overweight and obese subfertile women and will offer guidance to clinicians for the treatment of these patients.

Trial registration

Dutch Trial Register NTR1530  相似文献   
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