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71.
目的:对比野生型小鼠和成纤维细胞生长因子Ⅱ型受体(fibroblast growth factor receptor2,fgfr2)基因S252W突变型小鼠颅底软骨的生长发育情况,探讨fgfr2功能持续增强对小鼠颅底软骨发育的影响。方法:实验于2004-03/2005-04在解放军第三军医大学大坪医院野战外科研究所创伤中心实验室,创伤、烧伤与复合伤国家重点实验室完成。①fgfr2 小鼠和C57BL/6J小鼠交配后取F1代,利用聚合酶链反应方法进行fgfr2突变型小鼠基因型的鉴定,得到野生型和fgfr2受体功能获得型点突变型两组小鼠。②标本取材及处理:分别在两组实验动物中,取胚胎期16d(E16)、胚胎期17d(E17)、新生2d(P2)、新生8d(P8)的小鼠的颅底作为标本。一部分体积分数为0.75的乙醇溶液固定。另一部分标本行40g/L多聚甲醛固定,150g/L乙二胺四乙酸溶液脱钙,常规石蜡包埋、切片。③阿尔辛-茜素红骨架染色显示颅底整体骨骼的发育情况。软骨组织染为蓝色,骨组织染为红色。④脱钙骨切片后进行苏木精-伊红染色。未脱钙骨切片后进行Calcein染色,荧光显微镜下观察钙化组织的情况。⑤使用地高辛RNA标记试剂盒按照产品说明制备Col 10(Collagen 10)地高辛标记的互补RNA探针,对颅底软骨联结进行检测软骨分化标志基因表达情况的原位杂交。⑥组织切片染色结果使用SPOT Advanced软件进行数码拍摄。结果:①实验小鼠颅底发育的大体情况:fgfr2受体功能获得型点突变小鼠从胚胎后期开始就表现出短颅现象。②阿尔辛蓝-茜素红骨架染色、Calcein染色和苏木精-伊红染色显示,fgfr2受体功能获得型点突变小鼠出生后颅底软骨联结没有出现提前融合的现象,但是颅底软骨生长发育差,软骨细胞增生区、肥大区缩短。突变小鼠的颅底软骨发育障碍导致颅底骨组织的生长发育也出现障碍。③原位杂交:Col10在野生型和突变型小鼠颅底软骨的表达部位未见明显差异,但是这个软骨细胞分化标志基因的表达强度降低。结论:fgfr2 S252W点突变能够引起小鼠颅底软骨联结处的软骨细胞发育异常,导致颅底骨骼发育畸形。fgfr2可能具有调控软骨细胞系发育的功能,从而可能在骨骼发育、骨折修复等方面发挥重要作用。  相似文献   
72.
The development of laparoscopic surgery has generated the new field of study, laparoscopic anatomy. This article reviews the reported literature on laparoscopic anatomy and explores how it has evolved along with advances in abdominal surgery. In addition, the principal concerns in current laparoscopic anatomy research are discussed, including: (1) types of special adjacent anatomical structures; and (2) special surgical planes and anatomical landmarks. Understanding of systematic laparoscopic anatomy can pr...  相似文献   
73.
Oral Diseases (2010) 16 , 136–145 Objective: The oral cavity forms an indispensable part of the human microbiome, for its unique and diverse microflora distributed within various niches. While majority of these organisms exhibit commensalism, shifts in bacterial community dynamics cause pathological changes within oral cavity and distant sites. The aim of this review was to appraise the current and emerging methods of detecting bacteria of the oral cavity paying particular attention to the cultivation independent methods. Design: Literature pertaining to cultivation based and cultivation independent methods of oral bacterial identification was reviewed. Methods: The specific advantages and disadvantages of cultivation based, microscopic, immunological and metagenomic identification methods were appraised. Results: Because of their fastidious and exacting growth requirements, cultivation based studies grossly underestimate the extent of bacterial diversity in these polymicrobial infections. Culture independent methods deemed more sensitive in identifying difficult to culture and novel bacterial species. Conclusion: Apart from characterizing potentially novel bacterial species, the nucleic acid sequence data analyzed using various bioinformatics protocols have revealed that there are in excess of 700 bacterial species inhabiting the mouth. Moreover, the latest pyrosequencing based methods have further broadened the extent of bacterial diversity in oral niches.  相似文献   
74.
OBJECTIVE—To assess whether prandial insulin, in addition to basal insulin, has an effect on the rate of glucose appearance from a meal in people with type 1 diabetes.RESEARCH DESIGN AND METHODS—The rate of glucose appearance from a mixed meal (Rameal) was investigated in six adult (aged 24 ± 2 years), lean (BMI 23.6 ± 1.5 kg/m2) subjects with well-controlled type 1 diabetes (duration 7.9 ± 6.9 years, A1C 7.6 ± 0.9%) with/without prandial insulin. Actrapid was infused to maintain euglycemia before meals were consumed. Subjects consumed two identical meals on separate occasions, and Rameal was measured using a dual isotope method. [6,6-2H2]glucose was incorporated into the meal (0.081 g/kg body wt), and a primed constant/variable rate infusion of [1,2,3,4,5,6,6-2H2]glucose was administered. In the tests with prandial insulin, an additional bolus dose of Actrapid was given 20 min before the meal at 0.1 units/kg body wt.RESULTS—Insulin concentration with prandial insulin was significantly higher than during basal insulin studies (119 ± 16 vs. 66 ± 15 pmol/l, P = 0.03 by paired t test). Despite differences in insulin concentration, there were no differences in total glucose appearance (3,398 ± 197 vs. 3,307 ± 343 μmol/kg) or time taken for 25% (33.1 ± 3.3 vs. 31.7 ± 3.5 min), 50% (54.6 ± 3.5 vs. 54.1 ± 4.7 min), and 75% (82.9 ± 7.1 vs. 82.8 ± 5.8 min) of total glucose appearance. The fraction of the glucose dose appearing in the circulation was the same for basal (73 ± 8%) and prandial (75 ± 4%) study days.CONCLUSIONS—These results suggest that meal glucose appearance is independent of prandial insulin concentration in people with type 1 diabetes.Plasma glucose concentration is determined by several factors: the production of glucose by the body, the uptake of glucose by splanchnic and peripheral tissue, and the appearance of exogenous glucose from meals (1). Plasma insulin regulates the production and uptake of glucose (2,3), but its role in regulating rates of glucose appearance from meals (Rameal) is uncertain.Rameal is determined by the rate at which glucose is emptied from the stomach and absorbed across the intestinal membrane, and by the extent of extraction during first pass of the liver and other splanchnic tissues, before reaching the general circulation. The modification by insulin of any of these processes would act to regulate postprandial glucose levels and would be an important consideration for people with diabetes. In particular, for people with type 1 diabetes, the effect of insulin on Rameal has important implications for the timings of prandial insulin injections and the appropriateness of pre-/post-meal insulin dosing.Research in this area is limited and, although there is some in vitro and in vivo evidence that insulin plays a role in regulating glucose appearance in rats (46), these findings have yet to be reproduced in human studies. In people with poorly controlled type 1 diabetes, Rameal was normal and unchanged with intensive insulin therapy (7). However, these studies were designed to investigate the effects of longer-term hyperglycemia/insulin deficiency, and the effect of acute insulin deficiency on Rameal was not independently investigated.No study to date has examined the immediate independent effect of bolus exogenous insulin administration on Rameal in people with type 1 diabetes. This study therefore aimed to compare Rameal in the presence of prandial insulin with that measured at basal insulin concentrations in people with type 1 diabetes.  相似文献   
75.
Animal evidence indicates that green tea may modulate insulin sensitivity, with epigallocatechin-3-gallate (EGCG) proposed as a likely health-promoting component. The purpose of this study was to investigate the effect of dietary supplementation with EGCG on insulin resistance and associated metabolic risk factors in man. Overweight or obese male subjects, aged 40-65 years, were randomly assigned to take 400 mg capsules of EGCG (n 46) or the placebo lactose (n 42), twice daily for 8 weeks. Oral glucose tolerance testing and measurement of metabolic risk factors (BMI, waist circumference, percentage body fat, blood pressure, total cholesterol, LDL-cholesterol, HDL-cholesterol, TAG) was conducted pre- and post-intervention. Mood was evaluated weekly using the University of Wales Institute of Science and Technology mood adjective checklist. EGCG treatment had no effect on insulin sensitivity, insulin secretion or glucose tolerance but did reduce diastolic blood pressure (mean change: placebo - 0.058 (se 0.75) mmHg; EGCG - 2.68 (se 0.72) mmHg; P = 0.014). No significant change in the other metabolic risk factors was observed. The EGCG group also reported feeling in a more positive mood than the placebo group across the intervention period (mean score for hedonic tone: EGCG, 29.11 (se 0.44); placebo, 27.84 (se 0.46); P = 0.048). In conclusion, regular intake of EGCG had no effect on insulin resistance but did result in a modest reduction in diastolic blood pressure. This antihypertensive effect may contribute to some of the cardiovascular benefits associated with habitual green tea consumption. EGCG treatment also had a positive effect on mood. Further studies are needed to confirm the findings and investigate their mechanistic basis.  相似文献   
76.
Parent-child sexuality communication has been identified as a protective factor for adolescent sexual and reproductive health, including HIV infection. The available literature on this topic in sub-Saharan Africa is increasing; however a systematic review of studies has not been conducted. This article reviews the literature in the area of parental or caregiver and child communication about sexuality and HIV/AIDS in sub-Saharan Africa. A review of peer reviewed literature published between 1980 and April 2011 was conducted. Communication process studies investigating the frequency, content, style, tone of discussions, preferences, as well as associations with and barriers to sexuality communication are reviewed. In addition, studies which examine behavioral associations with parent-child sexuality communication, and intervention studies to improve parent-child sexuality communication are examined. The findings from process studies suggest wide variation in terms of frequency of discussions, with a range of socio-demographic and other factors associated with sexuality communication. Overall, findings demonstrate that discussions tend to be authoritarian and uni-directional, characterized by vague warnings rather than direct, open discussion. Moreover, parents and young people report a number of barriers to open dialogue, including lack of knowledge and skills, as well as cultural norms and taboos. Findings are less clear when it comes to associations between parental communication and adolescent sexual activity and contraception use. However, nascent indications from intervention research suggest positive findings with increases in frequency and comfort of discussions, among other outcomes. Gaps in the research are identified and discussed with implications for future studies.  相似文献   
77.
ABSTRACT Publication of the Royal College of Psychiatrists'guidelines for provision of psychotherapy training for general psychiatric trainees led to the implementation of the pilot scheme described in this paper. The scheme offered an experience of individual psychodynamic therapy, with group supervision, for the beginning therapist. The authors describe the induction programme, the group experience, the experience of being supervised, working with the patient and ending. A personal view is offered, aiming to provide an understanding of the nature and quality of this experience, highlighting its benefits and difficulties. Conclusions are drawn as to the usefulness of the scheme in personal and professional spheres and in relation to the Royal College guidelines.  相似文献   
78.
刘新泳  徐丽君 《药学学报》1994,29(2):153-157
In order to search for more ideal antiviral drugs,21 substituted pyriiT1idinone derivatives were designed and synthesized,among which 11 were not reported before. The cheinicalstructures were characterized by elemen tal and spectral analysis. The serum interferon - inducing activity was tested in mice. All 2-amino-5-bromo-6-substituted-4-(3H)pyrimidinone compounds were shown to have interferon inducing activity.The corresponding substituted pyrimidine thiones were less active.The new compounds of 6-sulfophenyl derivatives are soluble in、water, but the interferon-inducing activity are not higher than the original compound of ABPP.  相似文献   
79.
抗病毒药物2,5,6-三取代-4(3H)嘧啶酮衍生物的合成及诱导干扰素活性刘新泳,徐丽君(山东医科大学药学系济南250012)取代嘧啶酮类化合物是一类小分干扰素诱导剂,有抗病毒、抗肿瘤、杀菌抑霉、诱导干扰素和白介素、免疫调节等多种生物活性(1)。目前?..  相似文献   
80.
侯宁  徐丽君 《药学学报》1992,27(10):738-742
设计合成了新型缩氨基硫脲衍生物4-氨基-3-(呋喃-2)-5-巯基-1,2,4-三唑及其十种不同醛的Schiff碱衍生物,并进行了抑菌实验。结果表明:Schiff碱化合物结构中的甲亚胺基是该类化合物的活性功能基。苯环上更换不同的取代基对其活性有一定的影响,其中化合物4-(5-硝基亚糠基氨基)-3-(呋喃-2)-5-巯基-1,2,4-三唑(Ik)抗菌活性最高且抗菌谱最广;化合物4-亚水杨基氨基-3-(呋喃-2)-5-巯基-1,2,4-三唑(Ib)具有较强的抑霉活性。  相似文献   
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