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In vivo assessment of skin electroporation using square wave pulses.   总被引:5,自引:0,他引:5  
The application of short-duration high-voltage pulses to the skin has been shown to enhance transdermal drug delivery by several orders of magnitude and to transiently permeabilize cells in tissue. Both exponentially decaying (ED) pulses and square wave (SW) pulses have been applied. The latter have also been used for electrochemotherapy. To date, their effect on skin integrity has not been analyzed. The scope of this work was (i) to investigate the effect induced by SW pulses on the stratum corneum and the skin, (ii) to evaluate the safety issue associated with electroporation, (iii) to contribute to the understanding of drug transport. Biophysical techniques (transepidermal water loss, chromametry, impedance and laser Doppler velocimetry or imaging measurement) and histological methods were combined to provide a global picture of the effects. Ten SW pulses applied to the skin induced a mild impairment of the skin barrier function and a dramatic decrease in skin resistance. These changes were reversible. A transient decrease (<5 min) in blood flow was observed. Neither inflammation, nor necroses were observed. These studies confirm the tolerance of the skin to square wave pulses in vivo.  相似文献   
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目的:了解中国不同地区间中老年人群膝关节骨性关节炎患病危险因素。方法:调查时间为2005—07/08。①从中国六大行政区(西北,华北,华东。中南,东北,西南)选出六城市(西安,石家庄,上海。广州,哈尔滨市,成都),用分层多阶段整群抽样方法,抽取6218名40岁及以上具有正式户口常住男女人群进行膝关节骨性关节炎的流行病学问卷调查(包括一般情况、现病史、既往史、体格检查、X射线片检查情况和疾病诊断6个方面,共计94个问题141个变量指标),并对其中4808名有症状者进行X射线平片膝正侧位投照。②膝关节骨性关节炎诊断标准为临床症状阳性加X射线Kellgren & Lawrence分级二级及以上者。③计算患病率,并采用Epilnf06.0和SPSS 10.0软件对其中83个变量进行多因素非条件Logistfc回归分析,表示疾病与暴露因素之间联系强度的指标用比值比(OR),若OR〉1,说明疾病发生危险性增加,与暴露因素呈正关联;若OR〈1,说明疾病发生危险性减少,与暴露因素呈负关联。 结果:①六城市膝关节骨性关节炎总患病率为15.6%,其中西安7.7%,石家庄11.2%,上海9.8%。广州30.5%,哈尔滨16.9%,成都17.5%,各城市患病率比较差异显著(P〈0.01)。②Logistic回归分析膝关节骨性关节炎在大部分城市有共同的危险因素如年龄大(OR=1.032—1.181),使用蹲坑排便年限长(OR=1.021-1.077),体质量高(OR=1.048—1.073),和开始饮酒年龄大(OR=1.008~1.028);而从事专职体育运动(OR=1.651,西安),骨质疏松病史(OR=3.311,石家庄),吸烟(OR=2.654,石家庄),类风湿关节炎病史(OR=4.964,上海),文化程度高(OR=2.593,上海),女性(OR=2.510,广州),姐妹骨关节炎史(OR=13.251,哈尔滨),母亲骨关节炎史(OR=5.683,成都)等危险因素分别在不同地区出现. 结论:年龄大、使用蹲坑排便年限长、体质量高和开始饮酒年龄大是中国六地区膝关节骨性关节炎患病的共同危险因素,同时,不同地区主要危险因素又有一定差异。  相似文献   
14.

Background

The common bile duct traditionally is managed with T-tube drainage after choledochotomy and removal of common bile duct (CBD) stones, but this approach carries an associated tube-related morbidity rate, including bile leak, of 10.5–20 %. This study examined the safety and effectiveness of laparoscopic CBD exploration (LCBDE) followed by primary duct closure.

Methods

This is a retrospective analysis of 120 consecutive patients (81 female) who underwent LCBDE between October 2002 and October 2012. The duct primarily was closed in all patients. The results are given as median (range).

Results

Trans-CBD exploration was performed in 120 patients and all cases were successfully completed laparoscopically. The maximum diameter of the CBD was 9.4 (3–30) mm and the number of CBD stones detected was 3 (0–20). The biliary tree was clear at the end of exploration in 116 patients (96.7 %). The operating time was 122 (70–360) min. The mortality rate, morbidity rate, postoperative bile leak rate, rate of retained CBD stones after the primary procedure, and CBD stricture rate at a follow-up of 39.2 (2–82) months were 0, 8.3, 2.5, 3.3, and 0.8 %, respectively. The postoperative hospital stay was 2.1 (1–29) days.

Conclusion

Primary duct closure following LCBDE is safe, can be employed routinely as an alternative to T-tube insertion, and has a short hospital stay and low morbidity rate.  相似文献   
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广地龙中促进子宫收缩的成分   总被引:1,自引:0,他引:1  
徐叔云  孙鼎兴  尹留康  邢文 《药学学报》1964,11(11):729-734
本文研究了自广地龙中提出来的一种引湿性、淡黄色針状結晶(含量約0.2%)对平滑肌器官(特别是对子宮)的作用。介紹了該結晶的提取方法。該結晶0.1毫克加入25毫升Locke液中,能使已孕和未孕大鼠或豚鼠离体子宮角紧张度明显升高,0.3毫克可使之呈痙攣收縮状态。按1毫克/公斤給已孕和未孕麻醉家兔靜脉注射后15—30分钟,在位子宮紧张度升高,作用維持1.5—3小时。按8—10毫克/公斤注射,子宮紧张度立卽升高和血压急剧下降到零而死亡。9只慢性子宫瘻家兔靜脉注射(3—6毫克/公斤)或灌胃給药(10—20毫克/公斤)后15—45分钟,子宮收縮明显增强,作用維持1.5—3小时(注射給药)和7小时以上(灌胃給药)。多数实驗家兔在子宮兴奋同时有排便現象。該結晶对家兔在位腸管和大鼠后肢血管均有强烈兴奋作用,但对豚鼠支气管肌作用极弱。当給小鼠靜脉注射时,LD50为38.7毫克/公斤。  相似文献   
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INTRODUCTION: This study used reliable and validated instruments to compare pain severity in multiple sclerosis (MS) to that in other chronic painful conditions, and to examine relationships between chronic pain in MS and health-related quality of life (HRQOL). METHODS: Ninety-nine MS patients completed a self-administered survey comprised of the Medical Outcomes 36-Item Short-Form Health Survey, the Short-Form McGill Pain Questionnaire, and the Hospital Anxiety and Depression Scale. RESULTS: Pain severity was not different between MS patients with pain and rheumatoid arthritis (P = 0.77) or osteoarthritis (P = 0.98) patients. Chronic pain in MS was less often neurogenic than non-neurogenic, although severity of neurogenic pain was greater than that of non-neurogenic pain (P = 0.048). Chronic pain in MS was found to have no significant relationship to age, disease duration or disease course. Instead, we found that pain was correlated with aspects of HRQOL, particularly mental health (r = 0.44, P < 0.0001) versus physical functioning (r = 0.19, P > 0.05). Chronic pain was significantly related to anxiety and depression for females but not for males with MS. CONCLUSIONS: Chronic pain in MS is as severe as pain in arthritic conditions and is associated with reduced HRQOL. Thus, pain can be a significant symptom for MS patients and the need for treatment may be underestimated.  相似文献   
20.
Streptococcus pyogenes is an important bacterial pathogen afflicting humans. A striking feature is its extraordinary biological diversity, evident in the wide range of diseases it can cause and the antigenic heterogeneity present on its surface. The T antigens form the basis of a major serological typing scheme that is often used as an alternative or supplement to M typing. Unlike M typing, the genetic basis for T typing is poorly understood. In this report, the tee6 gene is localized to a position approximately equal to 3.3 kb downstream from prtF1 (or sfbI), which encodes the Fn-binding protein, protein F, a key virulence factor. Comparison of this portion of the genome with those of four additional strains reveals the presence of genes encoding a collagen-binding protein (Cpa) and a second Fn-binding protein (PrtF2 or PfbpI). This chromosomal region--here designated the FCT region--is approximately 11 to 16 kb in length and is flanked at both ends by long stretches of highly conserved sequence. For each of the five strains, the FCT region contains a unique combination of semiconserved loci, indicative of extensive intergenomic recombination. The data provide evidence that the highly recombinatorial FCT region of the S. pyogenes genome is under strong selection for change in response to the host environment.  相似文献   
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