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101.
目的:重症脑出血微创术后气管切开病人痰培养病原菌分布与耐药情况分析,其院内感染发生的原因、探讨防治对策。方法:应用痰培养检出的病原菌及耐药性分析。结果:重症脑出血微创术后气管切开病人下呼吸道感染41例,其中G-杆菌26例占63.4%,G 球菌15例占36.6%,其中金葡菌11例,药敏仍以敏感菌株为主,但耐药菌株有增多趋势。结论:重症脑出血微创术后气管切开病人下呼吸道感染以G-杆菌为主,G 球菌以金葡菌为主,仍以敏感菌珠为主,耐药有增多趋势。万古霉素对G 球菌,氨曲南对G-杆菌敏感性较敏感,故在培养结果未出来之前经验用药是非常重要的。  相似文献   
102.
肝硬化患者高胰岛素血症对血清瘦素水平的影响   总被引:3,自引:0,他引:3  
目的 探讨肝炎后肝硬化患者高胰岛素血症对血清瘦素水平的影响,以及瘦素在肝纤维化形成中的作用.方法 采用化学发光酶联免疫分析和酶联免疫吸附法分别测定30例肝炎后肝硬化患者的血清胰岛素和瘦素水平.同时选取健康体检者30例作对照组.并用HOMA模式计算胰岛素抵抗指数.结果 肝硬化患者血清瘦素、空腹胰岛素、胰岛素抵抗指数分别为(7.2±2.2)ng/ml、(17.3±6.8)mIU/L和3.97±0.48,显著高于对照组的(3.4±1.2)ng/ml、(9.7±4.1)rIU/L和1.98±0.11(P<0.01).肝硬化Child C级患者的血清瘦素水平明显高于Child A级和Child B级患者(P<0.01),其空腹胰岛素和胰岛素抵抗指数明显上升(P<0.01).结论 肝炎后肝硬化患者存在高胰岛素血症,其胰岛素和瘦素间的反馈调节失衡是导致肝硬化患者血清瘦素水平上升的重要原因之一,瘦素可能是肝纤维化形成的重要促进因子.  相似文献   
103.
高浓度瘦素自分泌诱导脂肪细胞瘦素抵抗的研究   总被引:1,自引:0,他引:1  
李小林  赵锋  巫国辉  袁铿 《中国美容医学》2007,16(12):1696-1699
目的:观察高浓度瘦素对人脂肪细胞分解代谢及脂肪蓄积的直接影响,探讨瘦素自分泌调节在肥胖发生中的作用。方法:取正常成人皮下脂肪组织,常规提取和培养前脂肪细胞,待细胞融合后诱导分化为脂肪细胞后分为二组:低浓度组、高浓度组;分别培养于瘦素终浓度为100ng/ml、1000ng/ml的培养液a中。于培养48h、72h收集培养液检测游离脂肪酸和甘油的浓度,取脂肪细胞行油红O染色并图像分析计算脂肪细胞中脂肪颗粒的积分光密度。结果:与低浓度组相比,瘦素作用48h、72h后,高浓度组培养液中游离脂肪酸浓度均下降[(0.16711±0.011900)mmol/L VS(0.20589±0.008738)mmol/L,(0.17544±0.013920)mmol/L VS(0.23567±0.026220)mmol/L,甘油含量均减少(28.1733±0.91377)μmol/L VS(30.2456±0.30084)μmol/L,(28.9367±0.79530)μmol/L VS(31.8567±0.79024)μmol/L],而脂肪颗粒积分光密度则升高(461136.89±12049.947 VS418570.33±5668.129,441566.56±5921.602 VS 390133.67±7001.304)。结论:高浓度瘦素长时程作用脂肪细胞,可延缓脂肪分解代谢,增加脂肪蓄积。高浓度瘦素经自分泌诱导脂肪细胞产生瘦素抵抗,可能对肥胖发生有重要影响。  相似文献   
104.
PURPOSE: This study evaluated the effect of different cements on resistance to dislodgment of crowns cemented on preparations lacking geometric resistance form. MATERIALS AND METHODS: A preparation that offered no geometric resistance form, with 20 degrees total occlusal convergence (TOC), 0.9 mm wide shoulder finish line, and a 2.5 mm axial wall height was created on an ivorine tooth using a milling machine. Ten metal test specimen die replicas and 10 standardized metal crowns with recipient sites for the application of external forces through a universal testing machine were fabricated. The crowns were cemented on the dies under 5 and 10 kg external loads, the marginal openings measured, loaded to dislodgment, and cleaned of cement. The process was repeated using zinc oxide and eugenol (ZOE), zinc phosphate (ZPh), resin modified glass ionomer (RMGI), and composite resin (CR) cements. RESULTS: Marginal openings under 5 kg cementation loads were 74.63 (+/-15.04) for ZOE, 75.98 (+/-18.20) microm for ZPh, 98.58 (+/-22.62) microm for RMGI, and 105.82 (+/-20.07) microm for CR cements respectively; under 10 kg cementation loads they were 57.62 (+/-15.86) microm, 59.55 (+/-15.41) microm, 95.00 (+/-19.52) microm, 101.30 (+/-12.52) microm respectively. Oblique dislodgment forces, measured with a Universal testing machine, were 40.18 (+/- 6.76) N for ZOE, 215.65 (+/-45.79) N for ZPh, 165.43 (+/-19.53) N for RMGI, and 181.54 (+/-30.75) N for CR respectively when crowns were cemented under 5 kg loads. The corresponding values for 10 kg loads were 38.62 (+/-4.19), 274.86 (+/-54.22), 139.70 (+/-21.71), and 160.40 (+/-21.21) respectively. Only zinc phosphate cement produced statistically enhanced resistance when crowns were cemented under 10 kg force (p value = 0.035). CONCLUSIONS: Under the conditions of the present study only crowns cemented with zinc phosphate displayed increased resistance to dislodgment on preparations lacking resistance form.  相似文献   
105.
咳嗽变异型哮喘多项检测指标的Bayes判别分析   总被引:1,自引:0,他引:1  
目的探讨咳嗽变异型哮喘(CVA)肺功能、气道弹性阻力、支气管激发试验、最大呼气峰流量(PEF)日内波动率[△PEFR(%)]、支气管肺泡灌洗液(BALF)细胞学以及血清IgE的变化特点及诊断意义。方法对22例CVA、20例慢性阻塞性肺病(COPD)稳定期患者以及20名健康成年人进行最大呼气流量-容积曲线(MEFV曲线)、气道弹性阻力、支气管激发试验、[△PEFR(%)]、BALF细胞学分析以及血清IgE测定。结果(1)CVA患者呼气流量指标[PEF、一秒用力呼气容积(FEV1)、FEV,/FVC、最大呼气中段流量(MMEF)]与健康对照组比较差异无统计学意义(P〉0.05)。CVA组气道弹性阻力增高,与健康对照组比较差异有统计学意义(P〈0.01),但与COPD组比较差异无统计学意义(P〉0.05);(2)CVA组患者气道反应性明显增高,支气管激发试验阳性,Mch—PC20-FEV1明显降低、[APEFR(%)]增大(〉20%)、BALF中嗜酸性粒细胞明显增高、血清IgE明显增高与健康对照组及COPD组比较差异有统计学意义(均P〈0.01)。结论气道弹性阻力、支气管激发试验、[APEFR(%)]、BALF细胞学以及血清IgE的测定有助于CVA的诊断且与COPD等的鉴别。根据Bayes判别结果,鉴别CVA与COPD的上述病因学指标作用大小依次为Mch—PC20-FEV1、JgE、[△PEFR(%)]、BALF嗜酸性粒细胞计数、FEV1/FVC、FEV1、PEF、MMEF和气道弹性阻力,其中主要为Mch—PC20-FEV1、IgE、[APEFR(%)]、BALF嗜酸性粒细胞计数。  相似文献   
106.
肿瘤多药耐药与细胞信号转导的研究进展   总被引:1,自引:1,他引:0  
肿瘤多药耐药是肿瘤治疗失败的重要原因,最近研究发现细胞信号转导通路在肿瘤细胞耐药形成的过程中具有重要作用,主要包括凋亡、NF-κB、MAPK、PI3K/Akt通路及肿瘤干细胞等方面,而应用相应的通路阻断剂逆转耐药将成为提高肿瘤治疗效果的亮点。本文主要对以上与肿瘤多药耐药相关的细胞信号转导通路作一综述。  相似文献   
107.
目的从蛋白激酶C(PKC)信号通路角度,探讨游离脂肪酸(FFA)引起肝脏胰岛素抵抗(IR)的可能机制。方法培养HepG2细胞,同时设立对照组、软脂酸(PA)组、高胰岛素组。软脂酸组、高胰岛素组分别用250μmol/L PA、5×10-7mol/L胰岛素处理24h。然后对照组、软脂酸组再根据胰岛素刺激前加( )与不加(-)PKC抑制剂白屈菜红碱盐酸盐(chelerythrine chloride,CC)5μmol/L预处理1h,随机分为两亚组:对照组(-)、对照组( )、PA组(-)、PA组( )。葡萄糖氧化酶法测定胰岛素刺激后12h葡萄糖消耗量,蒽酮法测定胰岛素刺激后3h点细胞内糖原含量,Western blotting技术检测15min点细胞内P-Ser473PKB、P-Ser21/9GSK-3α/β水平。结果PA组(-)与高胰岛素组葡萄糖消耗量无统计学差异(P=0.523)。葡萄糖消耗量、细胞内糖原含量、P-Ser473PKB、P-Ser21GSK-3α、P-Ser9GSK-3β水平均显示,PA组(-)与对照组(-)比较显著降低(P值依次为0.000,0.000,0.004,0.004,0.028),对照组( )与对照组(-)比较略有升高但无显著性差异;PA组( )与PA组(-)比较显著升高(P值依次为0.000,0.014,0.043,0.041,0.035)。结论PA(250μmol/L)体外成功诱导了HepG2细胞产生IR,PKC信号通路在FFA引起肝脏IR中起着重要作用。  相似文献   
108.
BACKGROUND: During the study of a family with hereditary factor (F)V deficiency (FV Amersfoort, 1102 A > T in exon 7) we identified an individual with 5% FV heavy chain antigen (FV(HC)) and 50% FV light chain antigen (FV(LC)). Further testing revealed that apart from the FV Amersfoort allele a second variant FV allele was segregating in this family, which encodes for a FV molecule with a reduced affinity for mAb V-23 used in the FV heavy chain ELISA (ELISA(HC)). OBJECTIVE: Identification and characterization of the molecular basis responsible for the reduced affinity of the variant FV for mAb V-23. METHODS: Family members of the proband were screened for mutations in the exons coding for the heavy chain of FV, after which the recombinant variant FV could be generated and characterized. Next, the cases and controls of the Leiden Thrombophilia Study (LETS) were genotyped for carriership of the variant FV. RESULTS: In the variant FV allele a polymorphism in exon 3 (409G > C) was identified, which predicts the replacement of aspartic acid 79 by histidin (D79H). Introduction of this mutation in recombinant FV confirmed that it reduces the affinity for binding to mAb V-23. The substitution has no effect on FV(a) stability and Xa-cofactor activity. In Caucasians the frequency of the FV-79H allele is approximately 5%. Analysis of the LETS revealed that the FV-79H allele is not associated with FV levels (FV(LC)), activated protein C sensitivity (using an activated partial thromboplastin time-based test) or risk of venous thrombosis (OR 1.07, CI 95: 0.7-1.7). CONCLUSION: The D79H substitution in FV should be considered as a neutral polymorphism. The monoclonal antibody V-23, which has a strongly reduced affinity for FV-79H, is not suitable for application in diagnostic tests.  相似文献   
109.
Insulin resistance Type A and short 5th metacarpals.   总被引:1,自引:0,他引:1  
BACKGROUND/AIMS: Insulin resistance is associated with a number genetic syndromes and a variety of defects of insulin action. METHODS: We describe three members of an extended family spanning two generations with insulin resistance Type A and short 5th metacarpals. The proband had secondary amenorrhoea, male pattern hair distribution, acne, hirsutism, deep voice, acanthosis nigricans, polycystic ovaries, diabetes, features of acromegaly, raised creatine kinase and triglyceride levels and short 5th metacarpals. Her growth hormone, adrenal steroid and testosterone levels were normal. The proband's daughter had severe acne, hirsutism, acanthosis nigricans, polycystic ovaries, raised triglyceride, glucose and testosterone level short metacarpals and normal insulin receptor gene. The proband's son had a muscular build, raised creatine kinase, hypertriglyceridaemia and short 5th metacarpals. His fasting insulin levels were normal but pro-insulin was raised. RESULT/CONCLUSION: There are many familial and genetic syndromes associated with insulin resistance. This family was diagnosed as having insulin resistance Type A. This family does not conform entirely to any of the previously described syndromes and a number of family members have the phenotype of short 5th metacarpals, which appears to be associated with the features of insulin resistance Type A.  相似文献   
110.
目的探讨清肝泻心滋阴润燥法对2型糖尿病患者血清脂肪细胞抵抗素及脂联素水平变化的影响及其与胰岛素抵抗的关系。方法入选患者随机分为治疗组30例,对照组30例,治疗组采用清肝泻心汤治疗,对照组采用文迪雅治疗2个月。用ELISA法检测并比较治疗前后两组的脂肪细胞抵抗素、脂联素的血清水平及其与血糖、胰岛素抵抗水平的关系。结果两组治疗后均能降低血糖(P<0.01),但两组间差值比较差异无显著性意义(P>0.05)。两组均能降低糖化血红蛋白,且治疗组明显优于对照组(P<0.01)。在改善胰岛素抵抗相关指标方面,两组治疗后均能降低胰岛素、C肽及血清抵抗素水平(P<0.01),升高胰岛素敏感性指数及脂联素水平(P<0.01),但两组间差值比较差异无显著性意义(P>0.05)。结论清肝泻心滋阴润燥法及文迪雅均能降低2型糖尿病患者血清抵抗素水平,升高脂联素水平,这些脂肪细胞因子的改变直接与2型糖尿病患者胰岛素抵抗的改善相关。  相似文献   
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