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991.
人工全膝置换在严重膝内翻畸形患者中的应用   总被引:6,自引:5,他引:1  
目的观察保留后交叉韧带人工全膝置换治疗严重膝内翻畸形患者的临床结果.方法回顾性分析1990年1月~1995年7月间严重膝内翻畸形骨关节炎患者(≥20°)人工全膝置换后的临床结果.假体为Miller-Galante-Ⅰ人工全膝(MG-Ⅰ,Zimmer公司).采用KSS评分对临床结果进行评估.结果38人56膝获完整随访,平均随访6(4~9)年.术前至最后一次随访,平均膝评分从33分提高到91分,其中84%优秀;平均膝关节功能评分自39增加到76分;两者的改善均有统计学意义(P<0.01).86%的患者膝关节活动度超过90°,多数病例(50/56)术后膝关节力线正常,6例残留5~10°内翻畸形.总翻修率21%(12/56),平均翻修时间为术后5.5年.其它并发症包括髌骨半脱位,膝前痛,浅表感染.无深部感染、假体松动及前后向不稳.结论保留后交叉韧带人工全膝可矫正严重膝内翻畸形,术后内、外向不稳问题常致假体早期失败.  相似文献   
992.
我国造血干细胞基础研究的新进展兼论干细胞可塑性   总被引:14,自引:4,他引:14  
1995年以来我国造血干细胞工程与相关的生物学领域的研究发展迅速。有关造血干 祖细胞基因表达的研究 ,上海国家人类基因组研究中心陈竺、陈赛娟等为正常和急性白血病人骨髓造血干祖细胞cDNA文库的基因表达建立了一套先进的工作体系。他们在许多白血病细胞系的干 祖细胞中发现了 30 0个新的相关基因。中山大学医学院李树浓、黄绍良等从人的桑葚期胚胎干细胞成功地诱导出造血细胞等。北京输血研究所裴雪涛等从成人和胎儿的骨髓分离出成年源干细胞 ,又进一步诱导分化为骨、软骨、脂肪和神经原细胞等。他们成功地构建了胎儿和成人间充质干细胞cDNA扣除文库 ,获得了胎儿和成人间充质干细胞的差异表达基因及在胎儿特异表达基因。中国医学科学院天津血液学研究所、国家血液学重点实验室赵春华等证实从胚胎胰腺、骨髓和肝脏中都可以分离出人间充质干细胞 ,又证明G CSF可以使输注的间充质干细胞在体内促造血重建。北京基础医学研究所毛宁等的实验不支持间充质干细胞可以“横向分化”。最近他们发现小鼠胚胎干细胞的体外分化重现了胚胎早期造血发生的生物学程序以及Smad5基因调控在胚胎造血发生中的必要性和多样性 ,又表明其上游配体TGF beta家族分子在胚胎发生中的作用和特点。本文针对干细胞可塑性研究作了评  相似文献   
993.

Background

Domestic fuel combustion from cooking and heating is an important public health issue because roughly 3 billion people are exposed worldwide. Recently, the International Agency for Research on Cancer classified indoor emissions from household coal combustion as a human carcinogen (group 1) and from biomass fuel (primarily wood) as a probable human carcinogen (group 2A).

Objectives

We pooled seven studies from the International Lung Cancer Consortium (5,105 cases and 6,535 controls) to provide further epidemiological evaluation of the association between in-home solid-fuel use, particularly wood, and lung cancer risk.

Methods

Using questionnaire data, we classified subjects as predominant solid-fuel users (e.g., coal, wood) or nonsolid-fuel users (e.g., oil, gas, electricity). Unconditional logistic regression was used to estimate the odds ratios (ORs) and to compute 95% confidence intervals (CIs), adjusting for age, sex, education, smoking status, race/ethnicity, and study center.

Results

Compared with nonsolid-fuel users, predominant coal users (OR = 1.64; 95% CI, 1.49–1.81), particularly coal users in Asia (OR = 4.93; 95% CI, 3.73–6.52), and predominant wood users in North American and European countries (OR = 1.21; 95% CI, 1.06–1.38) experienced higher risk of lung cancer. The results were similar in never-smoking women and other subgroups.

Conclusions

Our results are consistent with previous observations pertaining to in-home coal use and lung cancer risk, support the hypothesis of a carcinogenic potential of in-home wood use, and point to the need for more detailed study of factors affecting these associations.  相似文献   
994.
BACKGROUND: Retinal vein pulsation is often absent in glaucoma, but can be induced by applying a graded ophthalmodynamometric force (ODF) to the eye, which is elevated in glaucoma. AIM: To assess whether ODF has a predictive value in determining glaucoma progression. METHODS: 75 patients with glaucoma and suspected glaucoma were examined prospectively in 1996, and then re-examined at a mean of 82 months later. All subjects had intraocular pressure, visual fields, stereo optic disc photography and ODF measured on their initial visit. When venous pulsation was spontaneous, the ODF was said to be 0 g. At re-examination, central corneal thickness and blood pressure were also measured. Initial and subsequent optic disc photographs were compared and graded into those that had increased excavation and those that had remained stable. The relationship between increased excavation (recorded as a binary response) and the measured variables was modelled using a multiple mixed effects logistic regression. RESULTS: ODF at the initial visit was strongly predictive of increased excavation (p = 0.004, odds ratio 1.16/g, range 0-60 g), with greater predictive value in women than in men (p = 0.004). Visual field mean deviation was predictive of increased excavation (p = 0.044), as was optic nerve haemorrhage in association with older age (p = 0.038). Central corneal thickness was not significantly predictive of increased excavation (p = 0.074) after having adjusted for other variables. CONCLUSION: ODF measurement seems to be strongly predictive of the patient's risk for increased optic disc excavation. This suggests that ODF measurement may have predictive value in assessing the likelihood of glaucoma progression.  相似文献   
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Assays of metabolised cotinine are considered to be an accurate measure of exposure to cigarette smoke among pregnant women. We investigated the association and differences between the cotinine levels in maternal urine and blood, and the umbilical cord blood of three tobacco exposure groups at different stages of pregnancy. A prospective study was conducted among 398 pregnant women undergoing prenatal care in different trimesters at two medical centres and one regional hospital in central Taiwan. All 398 subjects (including 25 smokers, 191 passive smokers and 182 non-smokers) remained in the study up to the time of delivery; 384 of them delivered singleton live births. Cotinine levels were assayed in the maternal plasma and urine of the mothers at each trimester and in the cord blood of the newborns. All specimens were measured using a sensitive high-performance liquid chromatography. Cotinine concentrations in plasma and urine showed a significant dose-dependent difference among the three groups (non-smoker, passive and active smoker) and a trend that increased with gestation among the pregnant women. Significant correlations between cotinine concentrations in plasma and urine among the pregnant women in each trimester were found. In addition, the level of cotinine in umbilical cord blood was significantly correlated with that in maternal blood at term (r = 0.89, P < 0.001). A pattern of elevated cotinine concentrations in the plasma and urine of pregnant women from the beginning to the end of pregnancy was found, and this correlated significantly with the cotinine levels in the umbilical cord blood.  相似文献   
999.
This article describes the impacts of the Ministry of Health and Long-Term Care's End-of-Life Care Strategy on the quality of end-of-life (EOL) care services delivered by home care providers across the province of Ontario. We compared key home care services one year before the strategy's implementation with those one year after. In addition, we conducted a qualitative survey of all community care access centres, the main providers of home care, and nearly all EOL Care Network directors to assess improvements to EOL care at the system and client level. Results showed that the number of clients of EOL care served increased by 3,537 over the baseline year. Moreover, the total number of nursing visits, shift nursing hours and personal support hours increased by 26%, 31% and 47%, respectively, compared with the baseline year. The qualitative analysis indicated that increased collaborations and communication have enhanced integration, coordination and consistency of EOL care. Anecdotally, clients and families feel more supported navigating the healthcare system, and more of their wishes are being met. The strategy appeared to improve EOL care on multiple levels. However, several barriers and challenges remain. Further investments and research are needed to achieve reliable quality EOL care for all Ontarians.  相似文献   
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