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51.
AIMS: To estimate the prevalence and distribution of the metabolic syndrome (MS) in adolescents attending school in the north Indian city of Chandigarh. RESEARCH DESIGN AND METHODS: At total of 1083 adolescents attending school (aged 12-17 years) participated in a community-based cross-sectional survey. Anthropometric examination included height, weight, body mass index, waist circumference, hip circumference, waist-hip ratio and blood pressure measurement. A fasting blood sample was taken for measurement of glucose, insulin and lipid profile. Socio-demographic characteristics were investigated using a questionnaire. The metabolic syndrome was determined by the National Cholesterol Education Program Adult Treatment Panel III definition modified for age. RESULTS: The overall prevalence of MS in adolescents was 4.2%. However, the prevalence rose to 5.8% when the fasting plasma glucose cut-off was lowered to 5.5 mmol/l. There was no gender difference in the distribution of MS. When stratified by body mass index (BMI), 5.5% adolescents were overweight (BMI > or = 95th percentile), while 4% were at risk for overweight (BMI between 85th and 95th percentile). Of the overweight adolescents, 36.6% met the criteria for MS, while 11.5% at risk for overweight and only 1.9% of the normal population had MS (P < 0.0001). Low high-density lipoprotein was the most common and abdominal obesity the least common constituent of MS. There was a significant difference (P < 0.0001) between the prevalence of MS adolescents from low to high socio-economic strata. CONCLUSIONS: A substantial number (4.2%) of north Indian adolescents and 36.6% of overweight adolescents had MS. This poses a serious threat to the current and future health of these young people.  相似文献   
52.
目的 探讨丹红注射液对急性冠脉综合征(ACS)患者介入治疗后血小板活化和炎症因子的影响。  相似文献   
53.
目的:探讨心肌缺血患者外周血白细胞计数及活性与心肌缺血发生发展的相关性。方法:对74例心肌缺血患者进行回顾性统计,以白细胞计数lO×109/L分组,大于此数患者归于异常组,小于此数则属于正常组.把心肌缺血患者分为两组.一组为心肌梗死组,另一组为心绞痛组,以健康体检者为对照组,分别就患者组与健康对照组在ld~3d/4d~6d/7d—lOd/lld—14d分四个阶段进行白细胞计数及活性测定。结果:心肌梗死组的白细胞计数明显高于冠心病组及正常对照组;随着病情的减轻白细胞计数逐渐下降,其白细胞活性与其记数呈正相关;且心肌梗死组白细胞教异常的病例数明显高于冠心病组及正常对照组。结论:白细胞数及活性的升高参与了心肌缺血的病理生理过程。  相似文献   
54.
血小板活化与冠心病关系的研究进展   总被引:3,自引:0,他引:3  
病理性血小板活化与血栓性疾病密切相关,在心血管疾病中,这一病理生理过程不仅与冠心病的发生、发展有着非常重要的联系,而且对于该病的治疗策略的优化和近、远期预后等方面都有直接的影响。  相似文献   
55.
代谢酶基因多态性与肿瘤的关系是近来国内外研究的热点。代谢酶基因多态性使酶的活性发生改变,是胰腺癌遗传易感性的重要机制。现综述了与胰腺癌癌变过程中有关的代谢酶基因多态性与其易感性的关系。  相似文献   
56.
目的 研究成年男性血清尿酸水平与代谢综合征危险因素的关系.方法 对2006年在解放军总医院做健康查体的男性进行调查.记录病史并全面检查,无糖尿病者行标准75g葡萄糖耐量试验(OGTT),排除影响血尿酸的继发因素.根据血尿酸水平,分为高尿酸血症组与血尿酸正常组,比较两组代谢综合征各组分的差异,并将血尿酸水平与各组分进行Logistic回归分析.进一步将非糖尿病者根据血尿酸水平进行分层,比较不同血尿酸水平组代谢综合征组分水平、代谢综合征患病率,血尿酸水平与代谢综合征各组分的相关性.结果 入选的男性有1 399例,年龄56.3±21.0岁,其中高尿酸血症者占14.37%.随着血尿酸水平升高,代谢综合征检出率也显著增高(P<0.01).Logistic回归分析显示,高尿酸血症与肥胖(OR=1.998,P<0.01)、高血压(OR=1.562,P<0.01)、高甘油三酯血症(OR=1.529,P<0.01)呈正相关.在非糖尿病人群中,血尿酸水平不仅与肥胖、高甘油三酯血症、高血压检出率呈正相关,还与HOMA指数(r=0.081,P<0.05)呈正相关.结论 在本研究人群中,高尿酸血症与代谢综合征危险因素显著相关.  相似文献   
57.
PROBLEM : Human seminal plasma is known to exhibit immunosuppressive activity. Transforming growth factor β (TGF-β) has been identified as an immunosuppressive factor in human seminal plasma. Biologically active TGF-β represents a family of 25-kDa homodimeric proteins linked with disulfide bonds. TGF-β associates with high molecular weight proteins noncovalently to form a type of latency that is biologically inactive. Quantitative distribution of active form of TGF-β versus inactive latent form of TGF-β, and mechanism of the TGF-β activation in human seminal plasma remain to be elucidated. PURPOSE : To characterize seminal plasma latent form of TGF-β, including its concentration, and the mechanism underlying the activation of TGF-β. METHOD : Gel filtrations on ACA-34 and Biogel P-60 were used to fractionate seminal plasma. TGF-β was measured by enzyme immunoassay using antibodies specific for TGF-β1 and TGF-β2, respectively. Radioreceptor assay with recombinant human [125I]-TGF-β1 was applied to qualitatively identify TGF-β1. Kinetic experiments with various pH, temperature and time, along with protease inhibitors, were performed to delineate the activation mechanism of latent TGF-β. RESULTS : Human seminal plasma contained both TGF-β1 and TGF-β2, predominantly in latent form. The total concentration of TGF-β1 averaged 238 ng/ml versus an average of 18 ng/ml for TGF-β2. The in vitro activation or release of TGF-β1, from latent TGF-β1 was achieved only at acidic pH of <4.0, and was time and temperature dependent. At pH 3.7 and 37°C, a significant activation of latent TGF-β1 was achieved after an incubation of only 15 min, reached the maximum at 120 min, and the activated TGF-β1 remained relatively stable for at least 24 h. The activation was not inhibitable by a series of protease inhibitors examined, alone or in combination (e.g., phenylmethylsulfonyl fluoride, E-64, pepstatin, leupeptin, ethylenediamine tetraacetic acid). Competitive radioreceptor assay established the functional identity of TGF-β1 in human seminal plasma with recombinant human TGF-β1. CONCLUSION : Human seminal plasma TGF-β is biologically activated from high molecular weight latent TGF-β by acid pH. The acidic environment of female lower genital tract could represent an in vivo physiological condition for activation of seminal plasma TGF-β that may immunologically protect the integrity of sperm.  相似文献   
58.
In early infancy, complex disorders of acid base metabolism are more frequent than in any other age group, with a predisposition to metabolic acidosis due to an age-related low renal capacity for acid excretion and an unphysiologically high actual renal acid load in nutrition with common formulas. Recently in preterm and small-for-gestational-age infants, persistent maximum renal net acid excretion (NAE) with subnormal or normal blood acid base status, impaired weight gain, and adaptive hormonal reactions have been observed. Incipient late metabolic acidosis is one example of a mixed disorder of acid base metabolism with maximum renal NAE in early infancy. Alkali therapy is highly effective and can be realized both on an individual basis, using urine pH screening as a diagnostic criterium for maximum renal acid stimulation, or on a general preventive level using modified standard formula with a reduced actual renal NAE similar to that seen on alimentation with human milk. From an integrated point of view, the low glomerular filtration rate and renal capacity for acid excretion beyond the developmental age of more than 44 weeks, may well be interpreted as the result of a specific adaptation to breast feeding sparing energy, and thus an evolutionary advantage for the survival of mother and child. Received July 10, 1996; received in revised form and accepted October 7, 1996  相似文献   
59.
Increased numbers of polymorphonuclear granulocytes (PMN) in the airways, as measured by PMN content in bronchial lavage fluid (P less than 0.01), were found 3 h postoperatively in ten patients undergoing surgery for lumbar aortic aneurysms. An increase in plasma levels of the complement split product C3dg from 6 (0-19) AU/ml preoperatively to 20 (13-50) AU/ml 3 h after surgery (P less than 0.01), indicates an activation of the complement cascade. These changes were not accompanied by increased elastase activity in the bronchial lavage fluid or by major changes in pulmonary blood gas exchange or vascular resistance, indicating that massive PMN activation, analogous to that proposed in adult respiratory distress syndrome (ARDS) had not taken place. In conclusion, complement system activation and migration of PMN into the airways, as seen in connection with major vascular surgery, does not seem to contribute to ARDS-type pulmonary dysfunction.  相似文献   
60.
T2毒素在灌流大鼠肠肝中的首过效应和代谢动力学   总被引:3,自引:0,他引:3  
建立并用大鼠在体肠-肝灌流标本研究了T2毒素在大鼠肠肝中的首过效应和代谢转化动力学,T2毒素在大鼠肠肝中的主要代谢产物是HT2,3′-OHHT2和其葡萄糖醛酸结合物,T2毒素具有显著的肠肝首过效应,当毒素(42μg·ml~(-1))由上肠系膜动脉恒速单次灌流(8 ml·min~(-1))肠-肝标本时,穗态肝、肠抽提率分别为0.978和0.454,总有效清除率为7.91 ml·min~(-1),T2毒素在循环灌流大鼠肠-肝标本中的消除半衰期为6.5min,主要代谢产物HT2,3′-OHHT2的生成半衰期分别为8.5和38.5 min,结果表明,T2毒素经消化道中毒后,在肠和肝的首过代谢下能很快地转化为产物,因此,毒素在体内的毒效作用主要由其代谢产物表现出来。  相似文献   
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