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51.
回顾医学美学与美容医学形成独立的学科系统的十多年来的发展历程,认为这个新兴学科在“整体学科”方面还存在一些学术问题有待人们进一步探讨。并认为,所谓“整体学科研究”是遵循该学科发展的内在规律所进行的各项研究的总和,是该学科发展的灵魂。学者们的任务在于:通过“整体学科研究”寻求其学科内在规律,经一代代同道有志者坚持不懈的努力,达到学科完善的目的。  相似文献   
52.
以头孢呋辛钠为原料,从制备(R,S)-乙酸1-溴乙酯开始。经酯化反应的溶剂沉淀过程无须分离直接制得高纯度非晶型的头孢呋辛酯。本制备方法简便,适于工为化生产。  相似文献   
53.
With Streptococcus pneumoniae, moxifloxacin was 4- and 10-fold more effective than levofloxacin at restricting selection of resistant mutants and at killing resistant mutants, respectively. The selection frequency for first-step topoisomerase mutants was 1,000 times lower for moxifloxacin than for levofloxacin; this difference was lost when second-step mutants were selected.  相似文献   
54.
A genome-wide screen was conducted using a large white sample to identify QTLs for FNCS geometry. We found significant linkage of FNCS parameters to 20q12 and Xq25, plus significant epistatic interactions and sex-specific QTLs influencing FNCS geometry variation. INTRODUCTION: Bone geometry, a highly heritable trait, is a critical component of bone strength that significantly determines osteoporotic fracture risk. Specifically, femoral neck cross-sectional (FNCS) geometry is significantly associated with hip fracture risk as well as genetic factors. However, genetic research in this respect is still in its infancy. MATERIALS AND METHODS: To identify the underlying genomic regions influencing FNCS variables, we performed a remarkably large-scale whole genome linkage scan involving 3998 individuals from 434 pedigrees for four FNCS geometry parameters, namely buckling ratio (BR), cross-sectional area (CSA), cortical thickness (CT), and section modulus (Z). The major statistical approach adopted is the variance component method implemented in SOLAR. RESULTS: Significant linkage evidence (threshold LOD = 3.72 after correction for tests of multiple phenotypes) was found in the regions of 20q12 and Xq25 for CT (LOD = 4.28 and 3.90, respectively). We also identified eight suggestive linkage signals (threshold LOD = 2.31 after correction for multiple tests) for the respective geometry traits. The above findings were supported by principal component linkage analysis. Of them, 20q12 was of particular interest because it was linked to multiple FNCS geometry traits and significantly interacted with five other genomic loci to influence CSA variation. The effects of 20q12 on FNCS geometry were present in both male and female subgroups. Subgroup analysis also revealed the presence of sex-specific quantitative trait loci (QTLs) for FNCS traits in the regions such as 2p14, 3q26, 7q21 and 15q21. CONCLUSIONS: Our findings laid a foundation for further replication and fine-mapping studies as well as for positional and functional candidate gene studies, aiming at eventually finding the causal genetic variants and hidden mechanisms concerning FNCS geometry variation and the associated hip fractures.  相似文献   
55.

Objectives  

To investigate clinical effects and manual operational point of Bryan cervical disc prosthesis in Chinese, to observe the stability and range of movement (ROM) post-operatively.  相似文献   
56.
背景与目的:功能性消化不良(FD)被认为是一类由不同病理生理原因导致的多种机能紊乱而促发的症状。Rome Ⅱ委员会建议将具有同种病理生理学及临床特征的FD患划分为感觉明显疼痛组和感觉不适组两个亚组。该研究旨在分析显疼痛或感觉不适与病理生理学机制间的关系,评价是否考虑到个体的显性症状将会产生更好的结果。方法:持续性FD患(n=720;489例女性;年龄41.3±0.6岁)填写消化不良调查问卷并确定出最令人烦恼的症状。分析此显症状在人口统计学、临床、病理生理学特点上的相互联系(研究592例患幽门螺杆菌感染、胃排空情况,对332例患行胃敏感性、顺应性试验)。结果:根据Rome Ⅱ标准,22%疼痛明显,78%不适感明显。疼痛明显的患超敏性的发生率较高(44% vs 25%),且在这些病例中观察到的胃排空迟缓较少出现(16% vs 26%),但是有较多的重叠。详细分析表明可能有8种消化不良症状其中之一较为突出。  相似文献   
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59.
OBJECTIVE: To investigate the hemodynamic effects of a moderately low-salt diet in a 9-week, randomized, double-blind, crossover study in 20 hypertensive, ambulatory patients. METHODS: All subjects followed a 9-week, low-salt diet. During this period, they received capsules containing either lactose or salt in 4-week treatment periods, separated by a 1-week washout period. Hemodynamic and biological parameters were evaluated on the day of randomization and at the end of weeks 4 and 9. We defined a low-sodium diet (LSD) as a salt-restriction period with lactose capsules, and a normal-sodium diet (NSD) as a salt-restriction period with capsular salt supplementation. RESULTS: Blood pressure was significantly lower during LSD compared with NSD. This fall in blood pressure was associated with a decrease in peripheral resistance in carotid and forearm circulation. Brachial artery diameter was larger during LSD whereas carotid artery diameter remained unchanged. The changes in brachial artery were: (1) not related to blood pressure changes; (2) positively related to age, and (3) negatively correlated with baseline intracellular sodium content. CONCLUSIONS: These results suggest that moderate low-salt restriction is capable of decreasing blood pressure and peripheral resistance in carotid and forearm circulation. The increase in brachial, but not carotid, artery diameter following salt restriction suggests a difference in salt dependence among different arteries.  相似文献   
60.
应用不经胸食管钝性剥离拔脱术治疗26例咽下癌与高位食管癌,效果良好,术后5例发生开发症,其中颈部吻合口痿3例,暂时性咳呛1例,腹部切口局限裂开1例。手术死亡率7.6%(2/26)。介绍了手术方法,对不经胸施术、胃体缝缩、颈部食管胃Gambee氏吻合法应用进行了讨论。  相似文献   
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