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排序方式: 共有535条查询结果,搜索用时 31 毫秒
1.
血浆同型半胱氨酸水平与动脉粥样硬化和脑梗死的关系 总被引:1,自引:1,他引:0
目的 探讨血浆同型半胱氨酸(Hcy)水平与颈动脉粥样硬化和脑梗死关系.方法 2005-05~2006-02收治的91例脑梗死住院患者被列入研究对象.根据病灶大小分3组大片梗死21例,小片梗死44例,腔隙性梗死26例.根据颈动脉彩超检测结果将研究对象分为颈动脉斑块组34例,无颈动脉斑块组57例.全部患者测定血浆Hcy、血清叶酸、VitB12水平.分析血浆Hcy水平与脑梗死的危险因素、病灶大小、颈动脉粥样硬化斑块及血清叶酸、VitB12的关系.结果 血浆Hcy水平(1)与高血压、糖尿病、血脂、性别、年龄各指标无明显相关关系.(2)与脑梗死病灶大小无关.(3)与颈动脉粥样硬化斑块有关,有斑块34例,血浆Hcy(20.73±9.31)μmol/L,无斑块57例,血浆Hcy (15.46±11.4) μmol/L,前者高于后者(P<0.05).(4)与血清叶酸、VitB12水平呈负相关(r1s=-0.264,r2s=-0.16,P<0.05).结论 血浆Hcy水平与脑梗死病灶大小无关;Hcy水平升高与颈动脉粥样硬化斑块密切相关;与血清叶酸、VitB12水平呈负相关.高血浆Hcy血症可能是颈动脉粥样硬化的危险因素,但与脑梗死关系不明确. 相似文献
2.
低分子肝素对急性脑梗塞的影响 总被引:2,自引:0,他引:2
为了探讨低分子肝素(LMWH)在脑梗塞应用中的安全性及实用性,采用随机单盲对照方法,对39例急性脑梗塞病人,予LMWH治疗,并与低分子右旋糖酐治疗进行比较。结果显示:LMWH组对不同程度患者的神经功能恢复程度明显优于低右组(P<001),LMWH组头颅CT扫描脑梗塞体积缩小的范围比对照组明显(P<005),LMWH不减少血小板数量及纤维蛋白量,不引起出血,可改善血液流变学,降低微循环总积分值。总有效率8718%。 相似文献
3.
目的 研究 1986年 - 1996年 ,我国致病真菌菌群的变化情况。方法 1986年 1月 1日 - 12月 31日和 1996年 1月 1日 - 12月 31日在全国 2 5个省、市、自治区 4 0多个有代表性的单位对临床或现场确定的致病菌进行了动态研究 ,就病原菌变迁、各区动态情况和具体疾病等作了详细分析。结果 发现 10年间较易治疗的皮肤癣菌比例下降 ,而较难治疗的酵母菌和霉菌比例升高。结论 10年间致病真菌菌群的变化较大 ,我们应根据变化情况进行相应的研究及制定出相应治疗措施 相似文献
4.
Population-based case-control study of CYP11A gene polymorphism and breast cancer risk. 总被引:9,自引:0,他引:9
Wei Zheng Yu-Tang Gao Xiao-Ou Shu Wanqing Wen Qiuyin Cai Qi Dai Jeffrey R Smith 《Cancer epidemiology, biomarkers & prevention》2004,13(5):709-714
The CYP11A gene encodes the cholesterol side-chain cleavage enzyme (P450scc) that catalyzes the first and rate-limiting step for the biosynthesis of sex hormones. A pentanucleotide repeat [(TAAAA)n] polymorphism in the 5' of the CYP11A gene has been reported to be related to the risk of polycystic ovary syndrome, an inherited endocrine disorder characterized by hyperandrogenemia. We investigated the association of this polymorphism with breast cancer risk in a population-based case-control study conducted among Chinese women in Shanghai. Genotype assays were completed for 1015 incident breast cancer cases and 1082 community controls. Three common alleles with 4, 6, or 8 TAAAA repeats were identified in the study population. The frequency of the 8 repeat allele was more common in cases (12.6%) than controls (8.5%) (odds ratio = 1.6, 95% confidence interval = 1.3-1.9; P < 0.0001). Compared to subjects who did not carry this allele, adjusted odds ratios were 1.5 (95% confidence interval = 1.2-1.9) and 2.9 (1.3-6.7) (P for trend, <0.001), respectively, for those who carried one and two copies of this allele. This positive association was observed in both pre- and postmenopausal women and all strata defined by major breast cancer risk factors, including years of menstruation, body mass index, and waist-to-hip ratio. The results from this study indicate that the TAAAA repeat polymorphism near the promoter region of the CYP11A gene may be an important susceptibility factor for breast cancer risk. 相似文献
5.
Genetic polymorphisms in the estrogen receptor alpha gene and risk of breast cancer: results from the Shanghai Breast Cancer Study. 总被引:11,自引:0,他引:11
6.
A population-based case-control study of the Arg399Gln polymorphism in DNA repair gene XRCC1 and risk of breast cancer. 总被引:4,自引:0,他引:4
Xiao-Ou Shu Qiuyin Cai Yu-Tang Gao Wanqing Wen Fan Jin Wei Zheng 《Cancer epidemiology, biomarkers & prevention》2003,12(12):1462-1467
XRCC1 (X-ray repair cross-complementing group 1) is a base excision repair protein that plays a central role in the repair of DNA base damage and strand breaks. A common polymorphism (Arg-->Gln) at codon 399 of the XRCC1 gene has been previously linked to functional changes of the gene product and risk of cancers. We evaluated the association between XRCC1 Arg399Gln polymorphism and breast cancer risk in the population-based Shanghai Breast Cancer Study involving 1088 cancer patients and 1182 community controls. Genomic DNA from peripheral blood was used in genotyping assays, and exposure information and anthropometrics were collected through in-person interview. Plasma estrogen and sex hormone-binding globulin (SHBG) levels were measured for 190 postmenopausal breast cancer patients who had donated a pretreatment blood sample and 407 postmenopausal controls. Conditional logistic regression model was used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs) adjusting potential confounders. Approximately 27% of controls carried the variant allele (Gln), and cases and controls had a similar distribution for both allele type and genotype of this polymorphism. We found that 7.8% of cases and 6.3% of controls were homozygous for the variant allele, resulting in an OR of 1.20 (95% CI, 0.85-1.69). The OR was slightly higher among younger women [<45 years of age (OR, 1.39; 95% CI, 0.82-2.36)] than older women [> or = 45 years of age (OR, 1.07; 95% CI, 0.68-1.67)], but neither OR was statistically significant. No modifying effect of major breast cancer risk factors, including years of menstruation, body mass index, waist:hip ratio, and blood estrogen levels, was noted. Homozygosity for the variant Gln allele was associated with an elevated risk of postmenopausal breast cancer among subjects with a higher blood level of SHBG (OR, 3.27; 95% CI, 1.16-9.20) and a reduced risk among those with a lower level of SHBG (OR, 0.60; 95% CI, 0.18-1.97). The overall results of the study suggest that Arg399Gln polymorphism of the XRCC1 gene alone may not play a substantial role in the risk of breast cancer among Chinese women. 相似文献
7.
目的利用中国肿瘤登记地区1998-2007年胰腺癌发病登记数据分析胰腺癌发病趋势,并预测2008--2015年中国胰腺癌的发病情况。方法计算各年份胰腺癌的粗发病率,直接法计算中国人口标准化率,采用JoinPoint软件对中国肿瘤登记地区1998-2007年胰腺癌发病数据进行趋势分析,计算年度平均变化率。应用贝叶斯年龄一时期一队列模型对数据进行拟合,估计年龄、时期、队列参数效应并预测2008-2015年全国胰腺癌发病情况。结果1998-2007年城市男性粗发病率每年以1.86%的比例上升,中国人口标准化率上升趋势不明显;女性粗发病率每年上升2.1%,中国人口标准化率上升趋势不明显。农村男性粗发病率每年上升7.54%,中国人口标准化率每年上升4.82%;女性分别上升7.83%和5.48%。预测模型显示年龄效应、时期效应和队列效应均在胰腺癌发病中起重要作用。估计2015年新发胰腺癌103 428例,其中男性60 500例,女性42 928例,较2008年增加15 277例。结论中国胰腺癌发病率呈上升趋势,其中农村地区上升明显,城市地区上升速度略缓,到2015年总体上升趋势有所减缓,但短期内胰腺癌仍然是主要癌症。 相似文献
8.
Changqing Fang Rong Yang Zisen Zhang Xing Zhou Wanqing Lei Youliang Cheng Wei Zhang Dong Wang 《RSC advances》2018,8(16):8920
Thermoplastic polyurethane (TPU) was blended with recycled polyethylene terephthalate (rPET) to prepare rPET/thermoplastic polyurethane (TPU) composites. Meanwhile, multiple-walled carbon nanotubes (MWCNTs) were employed as a reinforcing filler to study the synergistic effect between CNTs and rPET/TPU composites. The effect of CNT content on the morphology and micro-structure of the composites was investigated using a scanning electron microscope (SEM) and X-ray diffraction (XRD). The thermal properties were characterized using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA). The mechanical properties were investigated using tensile tests and hardness measurements. The results showed that TPU was compatible with rPET. The existence of rPET changed the crystalline phase and affected the glass transition and crystallisation temperature of the TPU matrix. The rPET/TPU composites displayed poor thermal stability and tensile properties when compared to pure TPU. The addition of CNTs had no effect on the crystalline phase of the rPET/TPU composites. Due to the occurrence of interfacial adhesion between the CNTs and rPET, the CNTs displayed an offset effect on the reaction of rPET and decreased the rigidity of the molecular chain in the rPET/TPU composites. The thermal stability and tensile strength of the CNTs/rPET/TPU composites improved with an increase in CNT content.Multiple-walled carbon nanotubes (MWCNTs) were employed as a reinforcing filler to study the synergistic effect between CNTs and rPET/TPU composites. 相似文献
9.
目的探讨养阴活胃合剂对慢性萎缩性胃炎(CAG)模型大鼠血清炎症因子含量的影响及其作用机制。方法将实验动物随机分为6组:空白对照组、模型组、阳性药物对照组及中药低剂量组、中剂量组、高剂量组,每组16只。除空白对照组常规饲养、自由进食水之外,其余5组将2 g水杨酸钠加入100 m L的30%乙醇溶液中,给大鼠灌胃,每日1次,每次3 m L,配合隔日喂食不禁水法建立大鼠萎缩性胃炎模型,模型复制成功后中药治疗低、中、高剂量组分别喂饲养阴活胃合剂水煎剂0.74 g·kg-1·d-1、1.48 g·kg-1·d-1和2.22 g·kg-1·d-1。12 w后测定血清中IL-6、TNF-α、IFN-β及NOS2含量。结果养阴活胃合剂能够改善大鼠胃黏膜病理状态,使病变胃黏膜趋于正常。与空白对照组比较,各组IL-6、TNF-α、IFN-β及NOS2均明显升高(P<0.05),证明模型复制成功。与模型组相比,中药高剂量组TNF-α、IL-6、NOS2均明显降低,差异有统计学意义(P<0.05),中药中剂量组IFN-β降低,差异有统计学意义(P<0.05)。结论养阴活胃合剂可降低慢性萎缩性胃炎大鼠血清中炎症因子水平,而抑制炎症反应可能有助于慢性萎缩性胃炎病情的改善。 相似文献
10.
Dietary assessment, while traditionally based on pen-and-paper, is rapidly moving towards automatic approaches. This study describes an Australian automatic food record method and its prototype for dietary assessment via the use of a mobile phone and techniques of image processing and pattern recognition. Common visual features including scale invariant feature transformation (SIFT), local binary patterns (LBP), and colour are used for describing food images. The popular bag-of-words (BoW) model is employed for recognizing the images taken by a mobile phone for dietary assessment. Technical details are provided together with discussions on the issues and future work. 相似文献