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41.
取10具新鲜成年雄性家猪的脊柱标本,分两组观察鲁格氏棒经椎管行椎板固定和鲁格氏棒经横突椎板固定时,受破坏性屈曲力的数据,结果显示鲁格氏棒经椎管固定组在达1048.6(±20)N时,所固定的椎板发生骨折,部分钢丝断裂;鲁格氏棒经横突固定组达2058(±20)N时,仅发生棒弯曲,未发现任何部位骨折或钢丝断裂。临床治疗33例不稳定胸腰椎骨折脱位患者,术后X线片示骨折脱位复位满意,两周后患者可离床活动,随访2~2.5年未发现任何并发症。  相似文献   
42.
The objective of this work is to optimize the process parameters for detoxification of gossypol in cottonseed meal (CSM) by Candida tropicalis ZD-3 during solid substrate fermentation (SSF). The maximum detoxification efficiency of gossypol was achieved by employing the substrate, which consists of 70% of CSM, 20% of corn flour and 10% of wheat bran. The optimum fermentation conditions for gossypol detoxification are incubation period of 48h, incubation temperature at 30 degrees Celsius, inoculum level 5% v/w, moisture content of solid substrate 50% and pH in nature. Adding minerals solution to CSM substrate benefit fermentation detoxification.  相似文献   
43.
Factors affecting choice between a managed care organization(MCO) and a fee-for-service insurance plan were examined whenthe University of Geneva health insurance plan was transformedinto an MCO, in October 1992. A case-control study using a mailedquestionnaire (response rate 84%) was conducted to compare formermembers who joined the MCO (joiners, n=421) to former memberswho opted out in order to keep fee-for-service coverage (non-joiners,n=222). Non-joiners were more likely to be women (odds ratio(OR) from multivariate model was 1.15, p=0.50), to be born inSwitzerland (OR=2.04, p<0.01), to have an annual income >75,000Swiss francs (OR=2.00, p<0.01), to have a personal physician(OR=1.96, p<0.01) and to have consulted a specialist (OR=1.69,p=0.02) or used unconventional medicine (OR=4.59, p<0.01)in the past year. During the previous year, non-joiners hadmore health care visits than joiners (14.6 versus 9.1, p=0.01).Non-joiners reported better mental health and fewer complainedof persistent fatigue (OR=2.18, p=0.03). The choice of healthplan was strongly influenced by socio-demographic characteristics,past patterns of health services utilization and health status.The self-selection process was paradoxical: MCO joiners hadused fewer health care visits than non-joiners, but their self-reportedhealth status was worse. The differences we have observed betweenself-selected populations have important implications for thefinancial performance of competing health care delivery systems.  相似文献   
44.
During maturation, most proteins undergo different posttranslational modifications. In most simple cases, signal peptidases remove the signal or leader peptide from the precursors of the secretory proteins during their translocation across the ER membrane. For biologically active proteins, such as enzymes, regulatory and defense proteins, toxins, etc., additional maturation-regulating mechanisms were shown to proceed with limited proteolysis of inactive precursors by specific enzymes. A number of specific enzymes from different cell types selectively cleave proproteins at specific processing sites. In this work, we analyzed the sequences of protein precursors synthesized in the excretory glands of different animals and identified new, non-traditional processing sites. They differ from the motifs previously identified in secreted proteins' precursors and enabled us to reconstruct the sequence of events leading to the conversion of protein precursors into the final products (mature proteins). We also found that in animals, the maturation mechanism of secretory and excretory proteins and the set of enzymes involved are species specific. The processing sites identified in protein precursors in this study are useful for a more detailed genome analysis and more accurate mature protein sequence prediction.  相似文献   
45.
The conceptual and methodological framework proposed by Doss (this issue) makes valuable suggestions for strategic choices in future research. This commentary addresses conceptual and terminological distinctions adopted by Doss, as well as his criticism of add-on/ dismantling studies. We also suggest research topics and methodological developments that could be integrated in Doss's framework to further expand understanding of therapeutic change.  相似文献   
46.
海藻硫酸多糖的制备及其性质研究   总被引:11,自引:0,他引:11  
目的 建立一套从褐藻中提取海藻硫酸多糖(SP)简单可行的工艺流程。方法 采用乙醇分级提取和Sevage去除蛋白的方法分离、纯化SP,并用Molish反应、Fehling反应、茚三酮法和硫酸基法等鉴定SP产品,用苯酚硫酸法测定SP产品中的糖含量,硫酸基法测定SP产品中的硫酸基含量。结果 从褐藻中得到了SP产品,其得率为3%,SP产品的总糖含量高达85.4%,硫酸基含量为5.3%。结论 我们建立的SP制备工艺流程简单可行,所得产品确系硫酸酯化的海藻多糖。  相似文献   
47.
OBJECTIVE: Over the last 6 years, multidisciplinary teams (MDTs) have been established and play a key role in organizing the delivery of cancer care in the UK. There are no published data on the roles of their co-coordinators. To seek the views of colorectal multidisciplinary team co-ordinators (MDTCs) on what they do and how they do it. METHOD: Questionnaires were sent to the colorectal MDTC, or equivalent, in all 180 NHS hospital trusts in England and Wales where colorectal cancer surgery is performed. RESULTS: There was a 70% response rate. Seventy-one per cent of trusts now have a dedicated MDTC, whereas in 2002, only 40% had one. MDTCs generally keep their information on databases, but these differ, and are not coordinated with data entry into the national colorectal cancer database of the Association of Coloproctology of Great Britain and Ireland. In only 26 trusts does the MDTC communicate decisions to primary care, and the patients seem almost completely excluded from this process. CONCLUSION: The recently formed national MDTC Forum should grasp the opportunity of coordinating all of this well-intentioned but pluralistic activity to the benefit of patients, primary care and hospital teams. An effective MDTC with a robust database will be the key in achieving cancer waiting time targets with useful audit, thereby improving patient care.  相似文献   
48.
一氧化氮与卵巢生理   总被引:1,自引:0,他引:1  
NO是一种结构简单的气体,是脊椎动物体内已发现的分子量最小的生物活性分子。NO作为一种信使分子,生物作用广泛,在生殖系统发挥重要作用。本文着重介绍NO作为卵巢内重要的调节因子,在调节卵泡发育、卵母细胞成熟、排卵、黄体的形成与退化、激素合成等方面的研究进展。  相似文献   
49.
目的 探索牙槽突裂与鼻畸形同期整复的新方法。方法 对 4 2例牙槽突裂患者采用自体髂骨及松质骨充填牙槽裂隙 ,髂嵴软骨片覆盖并充垫塌陷的梨状孔外缘及鼻侧区 ,同时利用鼻前庭黏膜软骨复合组织瓣V Y推进法整复鼻畸形。结果  9~ 11岁患者牙槽突高度恢复平均为86 7% ,厚度恢复平均为 89 6 % ,牙槽突外形和功能为Ⅰ、Ⅱ级 ,尖牙在骨移植区萌出 ,梨状孔外缘鼻侧区低陷处高度恢复 ,鼻翼塌陷畸形恢复 ,鼻孔形态对称 ;12岁以上患者牙槽突高度恢复平均为70 1% ,厚度恢复平均为 71 7% ,牙槽突外形和功能为Ⅱ级、Ⅲ级 ;2例 18岁患者鼻背长轴、鼻端偏斜未能改善。结论 利用自体松质骨和软骨来修复牙槽突裂并同时进行鼻畸形整复 ,既能保证牙槽突高度、牙弓连续性的恢复 ,鼻畸形的改善 ,又能防止鼻背、鼻端长期畸形发展而造成难以矫正的偏斜 ,同时也能尽早消除因畸形给患者带来的心理障碍 ,是一种比较理想的整复方法  相似文献   
50.
就第Ⅱ报及第Ⅴ报提出的用于选取薄层色谱最佳溶剂系统的均匀设计法进行了进一步的改进及实验验证,使其更趋完善。结果表明,该法不仅适用于已知混合物,而且适用于未知混合物,是一种比较简捷、快速且行之有效的方法。  相似文献   
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