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31.
32.
Surface-active phospholipid as the lubricating component of lubricin   总被引:5,自引:0,他引:5  
To resolve the apparent conflict between a lubricating glycoprotein, 'lubricin', as the active ingredient in synovial fluid (SF) and surface- active phospholipid (SAPL) present in SF (and adsorbed to articular cartilage) as the boundary lubricant reducing friction to such low physiological levels, lubricin was isolated from bovine SF following the original procedure of Swann et al. (Arthritis Rheum 1981;24:22-30). Analysis of the lipid extract by thin-layer chromatography and phosphorus determination demonstrated a phospholipid component of 11.1 +/- 1.7% (N = 5) which corresponds very closely to the 9.2-13.0% of lubricin which had hitherto remained unidentified and which has previously been shown to be transferable to the articular surface to impart lubrication. These results would appear to resolve any theoretical conflict in that lubricin is, indeed, an active ingredient within SF. Yet, as a large water-soluble molecule, it really functions as a carrier for the highly insoluble SAPL which it deposits on the articular surface as the oligolamellar layer visualized in previous studies. However, it is this deposited SAPL, rather than lubricin, which actually lubricates.   相似文献   
33.
目的分析影响大学生饮酒模式的因素,针对饮酒教育及酒精政策提出建议。方法采用整群抽样方法,选择来自北京和郑州的530名大学生完成有效问卷调查。采用 Epidata 录入数据,SAS 12.0和 R 2.7.2进行数据描述和分析。结果74.5%的大学生在过去1年内饮过酒,啤酒是饮酒者的主要选择(85.9%),餐馆和家里是饮酒比较频繁的场所,饮用酒多来自同学/朋友及家庭成员提供,25.3%饮酒者并无特别原因饮酒,各有约1/5的饮酒者是出于社交目的或喜欢饮酒的感觉。认为“饮酒有助于社交暠或“饮酒促进交流暠者、父母及同学/朋友饮酒者、来自农村地区或小城镇者及吸烟者更容易发生饮酒行为(均 P 〈0.05),男生大学生、规律饮酒者更容易遭遇强迫劝酒场面、更易发生醉酒(均 P 〈0.05)。超过一半饮酒者出现酒后脸红、肌肉软弱无力等生理反应,饮酒对被调查大学生产生的社会心理影响依次是记忆丧失(23.9%)、宿醉(14.6%)、做了后悔的事(低于10%)等。结论目前大学生仍保持着一种低风险饮酒模式。大学生饮酒教育应提供关于饮酒利弊的科学信息,使其对饮酒保持一种现实的期望。应制定针对性酒精政策和教育鼓励和支持低风险且满足社交功能的饮酒模式,控制高风险饮酒模式。  相似文献   
34.

Objectives

To understand the vaginal bleeding/spotting experiences of postmenopausal (PM) women taking estrogen plus progestin therapies (EPT) and develop measures to assess these symptoms and their impact on women's daily lives in four countries.

Design

(1) Concept elicitation interviews were conducted with PM women in the US (n = 14), Italy (n = 15), Mexico (n = 15) and China (n = 15) to explore vaginal bleeding/spotting symptoms associated with EPT. The Post-Menopausal Bleeding Questionnaire (PMBQ) was also debriefed to evaluate understanding and comprehensiveness. (2) Based on concept elicitation, a single item electronic daily diary was developed and the PMBQ modified to form a 12-item impact measure. (3) The measures were pilot-tested and then cognitively debriefed with US women receiving EPT. All qualitative data was subject to thematic analysis.

Main outcome measures

The Vaginal Bleeding/Spotting Daily Diary, (VBS-DD) and Post-Menopausal Bleeding Impact Questionnaire (PMBIQ) were developed in this study.

Results

Concept elicitation identified vaginal bleeding and spotting as important symptoms for women taking EPT, impacting their emotional wellbeing, social life, ability to move freely, clothing and sexual activity. Based on pilot testing and cognitive debriefing, women demonstrated good understanding of the VBS-DD and the PMBQ was reduced to 10 items due to conceptual redundancy.

Conclusions

Women taking EPT in the US, China, Mexico and Italy reported vaginal bleeding/spotting symptoms that have a detrimental impact on their quality of life. Two new measures were developed to assess the severity and impact of vaginal bleeding/spotting specific to EPT. This work highlights the need for EPT-related symptoms to be a part of treatment decision-making.  相似文献   
35.
AIMS: To compare the effectiveness of thermal balloon ablation (TBA) and levonorgestrel intrauterine system (LNG-IUS) in the management of idiopathic menorrhagia and changes in pictorial blood loss assessment chart (PBAC) scores in patients who had failed on oral medical treatment. METHODS: Phase III, single-centre, open randomised controlled trial. Following full screening and evaluation of 104 women, 33 were randomised to TBA and 33 to LNG-IUS. Primary outcomes were changes in PBAC scores from baseline to 12 months. Secondary outcomes were changes in haemoglobin and serum ferritin, at six months, continuation with treatment and hysterectomy rates at two years and changes in PBAC scores at three, six and nine months. RESULTS: All patients randomised had a PBAC score of > or = 120. At all assessment times, median PBAC scores were less than baseline, the greatest reductions being seen at 12 months for both treatments. When the median PBAC for the LNG-IUS (26 (0-68)) was significantly different to the median PBAC for the TBA cohort (62 (0-142)) P < 0.001. Irregular bleeding problems were the most common reason for discontinuation of the LNG-IUS and resulted in more women (39.8%) seeking other treatment by two years than the TBA (23.1%) (P < 0.05) and more undergoing a hysterectomy (20.7% vs 13.3%, respectively) (p > 0.05). Patient acceptability of the LNG-IUS and TBA was similar at 12 and 24 months in terms of their perceived satisfaction of effect on menorrhagia. CONCLUSIONS: Both TBA and LNG-IUS achieved significant decreases in PBAC scores, with those for the LNG-IUS being significantly greater at 12 months. However, prolonged days of bleeding resulted in fewer women continuing with the LNG-IUS at two years.  相似文献   
36.
37.
IntroductionRecently, there has been much discussion in the literature about how to determine the meaningfulness of results generated from a patient-reported outcome measure. A number of reviews have shown that there are two main approaches: anchor- and distribution-based approaches for determining the minimum important difference (MID) for a new measure. There are issues with calculating an MID using each method: Will the two approaches give the same estimate? If the estimates differ, how do you decide on one estimate? Would asking patients directly be more beneficial?AimA case study was presented to address these issues based on a newly developed diary assessing number of satisfactory sexual events (SSEs) per week in women with hypoactive sexual desire disorder (HSDD).MethodsAnchor- and distribution-based estimates were generated from data gathered in two double-blind, placebo-controlled, parallel group trials for the treatment of HSDD (N = 788). A novel interview study was used to ask women directly about an MID for SSEs (N = 77).Main Outcome MeasuresDefining the MID for an SSE diary in women with HSDD.ResultsThe estimates varied, producing a range of mean MID estimates between 0.04 and 0.46 SSEs per week.ConclusionsWe recommend that rather than defining the MID, a range should be selected from the set of estimates formed by the limits of the 95% confidence intervals. Symonds T, Spino C, Sisson M, Soni P, Martin M, Gunter L, and Patrick DL. Methods to determine the minimum important difference for a sexual event diary used by postmenopausal women with hypoactive sexual desire disorder.  相似文献   
38.
Leptospira were successfully isolated from the urine of an Indian patient who had been clinically diagnosed as having leptospirosis. In an attempt to determine the source of this infection, 28 rats (Rattus rattus) and 58 bandicoots (Bandicota bengalensis) living in the vicinity of the patient's home in Avadi, a suburban area of the city of Chennai (Madras), India, were then investigated. Each animal was checked for infection by microscopical examination of fresh and stained urine, serological analysis of serum, and the culture of urine and kidney samples. Direct, dark-field, observation of fresh urine samples and examination of urine samples after Fontana's silver staining were found to be the least sensitive of the tests used. The results of the serological microscopic agglutination test (MAT) indicated that four (14.3%) of the rats and nine (16.1%) of the bandicoots had significant agglutinins, predominantly for the serogroups icterohaemorrhagiae and autumnalis. Leptospira were isolated from at least one culture of samples from one rat and each of four bandicoots. Each of these rodent isolates and the human isolate were typed as Leptospira interrogans serovar autumnalis.  相似文献   
39.
In a series of 38 nonmetastasizing and 29 metastasizing endometrial cancers, histologic subtype, aneuploidy, nuclear grade, and depth of myometrial invasion were the features most distinctly separating these two groups of patients. The most important factor was histologic type: papillary, papillary serous, adenosquamous, clear cell, and diffusely infiltrating carcinomas were strongly correlated with metastasis using chi square analysis. Nuclear grade 3 and deep myometrial invasion were similar to each other in sensitivity and predictive value, and both were also strongly correlated with metastatic risk. Aneuploidy, also correlated with metastasis, was similar to nuclear grade 3 and deep myometrial invasion in predictive value but was more sensitive. DNA analysis appeared to be most useful when histologic studies were inconclusive in assigning a high degree of risk. Twice as many aneuploid carcinomas having nuclear grade 2 (intermediate risk) morphology proved to be metastatic. A similar relationship was found with deep myometrial invasion. A quantitative correlation between the DNA index and the risk of metastasis was found; a DNA index above 1.5 was a strong attribute of the metastatic group.  相似文献   
40.
The ultrafast echo-planar magnetic resonance imaging technology, developed and built in Nottingham, has been used to produce the first snapshot images of the human fetus in utero. The imager, operating at a proton resonance frequency of 22 MHz, produces transaxial views in 64 or 128 milliseconds. These images comprise either 64 x 128 or 128 x 128 pixels with an in-plane resolution of 3 x 3 mm2. The slice thickness is 10 mm. Fetal scans of up to 32 contiguous slices are produced in a few minutes. These have been used to study the internal structure of the uterus and the fetus in a range of cases with gestations ranging from 26 weeks to term. Echo-planar imaging seems particularly suitable as an imaging modality since its high speed obviates image blurring arising from fetal motion.  相似文献   
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