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1.
目的:探讨龙胆紫染色区分存活精子和死亡精子可能性,以提供一种判定精子存活率的新方法,为男性精液检测和质量评价提供依据。方法:采用不同浓度的龙胆紫溶液对精液样本染色,在光学显微镜下观察染色结果,讨论区分存活精子和死亡精子的标准,并计数一定数量的总精子数,计算存活率,并将计算结果与标准方法比较。结果:经过龙胆紫溶液(0.05%,M/V)染色后在显微镜下存活精子呈现淡蓝色,而死亡精子呈现深紫色,计算获得的存活率与伊红染色法(0.5%,M/V)的结果比较差异统计学意义(t=0.862,双侧P=0.403)。结论:一定浓度的龙胆紫染色后能够清楚地区分存活精子和死亡精子,该法获得的精子存活率结果可靠,龙胆紫染色法可以作为一种新的分析精子存活率的方法。  相似文献   
2.
拉萨市藏、汉民族血脂水平的比较   总被引:2,自引:0,他引:2       下载免费PDF全文
 目的 调查分析拉萨市藏、汉民族间血脂水平及其异常检出率的差异,为该地区血脂异常症的预防提供客观依据。方法 选取拉萨市藏(Tibetan,T)、汉民族(Han,H)1 228例体检人群为调查对象,其中藏族559例,汉族669例,按血脂测定标准化方法测定的血清总胆固醇(total cholesterol,TC)、三酰甘油(triglycerin,TG)、高密度脂蛋白胆固醇(high-density lipoprotein cholesterol,HDL-C)及低密度脂蛋白胆固醇(low-density lipoprotein cholesterol,LDL-C) 4项指标的血脂水平;按2007年《中国成人血脂异常防治指南》将研究对象分为4个年龄组,界定4项血脂异常标准值,比较藏、汉民族各年龄组血脂异常检出率的差异。采用协方差分析和χ2检验比较两民族间血脂存在的差异。结果 汉族TG水平高于藏族(P≤0.001),HDL-C水平低于藏族(P<0.001);藏族TC和LDL-C水平均高于汉族 (P<0.001、P=0.013)。藏族男性青年组、中年组、老年前期组TC异常检出率均显著高于汉族(P<0.001),藏族男性中年组和女性青年组、中年组TG异常检出率反而比汉族高(P<0.001、P<0.05、P<0.001);汉族男性青年组、中年组、老年前期组HDL-C异常检出率明显高于藏族(P<0.001)。结论 藏族是混合型高脂血症的高危人群,尤其藏族男性;汉族男性是低HDL-C血症的高危人群。  相似文献   
3.
AIM:To investigate the relationship between CD14-260and-651 polymorphisms and the risk of developing gastric cancer.METHODS:DNA was extracted from peripheral blood samples obtained from 225 Tibetans with gastric cancer and 237 healthy Tibetans,and analyzed using the polymerase chain reaction/ligase detection(PCR/LDR)method to determine the genotypes at-260 and-651loci of the CD14 promoter.The allele frequencies,genotype frequencies,and haplotypes were analyzed for their association with gastric cancer risk using online SHEsis software.The luciferase reporter assay and point mutation analysis were used to construct in vitro plasmids expressing a C/T homozygote at the-260 lo-cus of the CD14 promoter.RESULTS:The frequencies of CC,CT and TT genotypes in the CD14-260 C/T locus in gastric cancer patients were 19.1%,38.7%and 42.2%,respectively,whereas they were 33.3%,32.5%and 34.2%,respectively,in healthy control subjects.CT genotype carriers were more frequently found among gastric cancer patients than healthy controls(OR=2.076;95%CI:1.282-3.360).Also,TT genotype carriers were more frequently found among gastric cancer patients(OR=2.155;95%CI:1.340-3.466).Compared to the C allele of CD14/-260,the T allele was associated with an increased risk for gastric cancer(OR=1.574;95%CI:1.121-2.045).Furthermore,the frequencies of CC,CT and TT in the CD14-651 C/T locus in gastric cancer patients were 64.4%,29.3%and 6.2%,respectively,while they were 56.5%,35.0%and 8.4%,respectively,in the healthy control subjects(P>0.05).Data obtained using the luciferase reporter assay showed that the p260T homozygote was associated with greater CD14 promoter activity(P<0.01).CONCLUSION:CD14/-260 polymorphism is associated with gastric cancer risk in Highland Tibetans and affects CD14 promoter activity,thereby regulating CD14expression.  相似文献   
4.
目的 通过检测高原世居藏族人群CD14基因全长的序列信息,了解该地区藏族人群CD14基因单核苷酸多态性变化的遗传特点.方法 采用直接测序的方法检测40例西藏高原世居藏族人群CD14基因全长,将测序结果与美国国家生物技术信息中心(NCBI)及国际人类基因组单体型图计划(HapMap)数据库比对,确定高原藏族CD14基因SNP位点的位置、类型和频率,并与不同人群SNP等位基因频率进行分析比较.结果 高原世居藏族人群CD14基因总有效测序长度约为4259 bp,共发现9个CD14基因SNP位点,其中有6个位点在NCBI的dbSNP数据库中已经存在,新发现3个SNP位点分别为:SNP04 (2755 T>G)、SNP07(3801 T>C)、SNP08 (4192 T>A).通过9个位点计算出4个主要单倍型,分别是CAGTCCTTG,频率为36.1%;CGGTCCTTG,频率为28.8%;CGGTCCTTC,频率为5.8%;CGATCCTTG,频率为3.8%.不同人群等位基因分析比较发现:在rs2563298位点,携带A等位基因在高原藏族人群的分布频率显著低于中国汉族(P=0.016)、欧洲(P =0.000)、日本(P =0.002)和非洲人群(P=0.001);在rs2569190位点,高原藏族人群携带G等位基因显著低于非洲人群(P =0.001),而与中国汉族(P=0.755)、日本(P =0.635)和欧洲人群(P=0.467)分布相似,差异无统计学意义.在rs2569192位点,C等位基因在高原藏族人群低于欧洲人群(P =0.035),而与中国汉族(P =0.837)、日本(P =0.266)和非洲人群(P=0.064)分布相似差异无统计学意义.结论 高原世居藏族人群CD14基因SNPs分布具有自身的遗传特征,本项研究将为进一步探讨高原地区藏族人群CD14基因相关疾病发病机制提供科学依据.  相似文献   
5.
为了“奥毛塞”在医疗、食品保健、美容等领域更好的应用,以及对“奥毛塞”的化学成分、药理作用、栽培与保健等方面的研究进展进行综述。通过文献查阅,可知奥毛塞主要成分以木脂素类和黄酮类为主,具有抗肿瘤、抗菌、抗病毒、等药理作用。在妇科疾病和营养保健、美容等方面更是有着不错的潜力。该综述可为“奥毛塞”的研究和开发提供参考。  相似文献   
6.
The chemical constituents of the traditional Tibetan medicine of Saussurea medusa Maxim. (Compositae) were investigated and a new flavonoid glucoside, together with 14 known compounds, was isolated. The structure of the new compound was established as 6″-O-crotonoylhomoplantaginin by using one- and two-dimensional nuclear magnetic resonance spectroscopy and mass spectrometry analyses.  相似文献   
7.
There is strong evidence to support the idea that the renin-angiotensin system (RAS) plays an important role in the pathogenesis of essential hypertension (EH) and its complications. However, existing data about the association of angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism with blood pressure is conflicting, mainly due to racial differences and environmental exposure status. We therefore conducted a case control study to observe the relationship between ACE I/D polymorphism and EH in a Tibetan population who live in relatively isolated areas and are genetically homogeneous. The study was conducted at stable residential communities in the urban district of Lhasa, the capital of the Tibet autonomous region, China, and 106 unrelated EH patients and 135 normotensIve subjects were recruited. PCR, PCR/RFLP and PCR-SSCP were carried out to study the association between RAS genes and EH. Frequencies for the DD, ID and II genotypes were 27, 47 and 29 in hypertensive subjects, and 15, 60 and 48 in normotensive subjects, respectively. Derived allele frequencies for the I and D alleles were 0.51 and 0.49 in hypertensive subjects and 0.64 and 0.36 in normotensive subjects. There were significant differences in genotype distribution and derived allele frequency between these two groups. The genotype and allele frequencies of the ACE gene differed significantly between hypertensive and normotensive females (p>0.05), but there were no differences in males. In females, the DBP and MAP level were significantly higher for the DD than for the ID and II genotype, and SBP was significantly higher for the DD than for the II genotype. But in males, there were no significant differences in blood pressure among ACE genotypes. The results showed a significant association between the D allele of the ACE gene and hypertension in Tibetan women but not in Tibetan men.  相似文献   
8.
An improved HPLC-DAD-ESI-MS(n) method has been developed to simultaneously quantify eight major compounds in Saussurea tridactyla Sch.-Bip. ex Hook. f. which has long been used as a traditional Tibetan medicine. This method was validated to be sensitive, precise and accurate with the LODs of 0.11-5.01 microg/ml, the overall intra-day and inter-day variations less than 2.70%, and the overall recovery over 98.0%, respectively. The correlation coefficients (r(2)) of the calibration curves were higher than 0.991. This newly established method was successfully applied to reveal the difference in the chemical profiles and contents of these analyses in S. tridactyla from different localities. In addition, by comparison UV and MS spectra with those of authentic compounds and literatures, a total of fourteen peaks were identified. It can be concluded that this method was effective to ensure the safety and efficacy consistency of S. tridactyla, and can be applied to other traditional Tibetan medicinal plants from different resources in Tibet.  相似文献   
9.
目的 调查日喀则地区小儿急性喉炎的发病特征,并对其治疗方案进行优化。方法 搜集日喀则地区的小儿急性喉炎患者,分析患者病情与海拔、温度、湿度等的关系。将3个月~3岁的Ⅰ~Ⅱ度喉梗阻病例分组,分别给予地塞米松静脉滴注和吸入用布地奈德混悬液(普米克令舒)雾化吸入,比较2组间的喉梗阻恢复时间。结果 经多因素回归分析,日喀则地区小儿急性喉炎患者的病情严重程度与海拔、温度、湿度等因素无明显相关,发病率与季节分布重合。吸入用布地奈德混悬液雾化吸入组较地塞米松静脉滴注组喉梗阻恢复时间快,2组间的差异具有统计学意义。结论 日喀则地区的小儿喉炎发病与季节相关。患者病情严重程度与自然环境因素无关。吸入用布地奈德混悬液雾化吸入可以减少患者的痛苦,且治疗效果确切。  相似文献   
10.
Although substantial progress has been made in the identification of genetic substrates underlying physiology, neuropsychology, and brain organization, the genotype–phenotype associations remain largely unknown in the context of high‐altitude (HA) adaptation. Here, we related HA adaptive genetic variants in three gene loci (EGLN1, EPAS1, and PPARA) to interindividual variance in a set of physiological characteristics, neuropsychological tests, and topological attributes of large‐scale structural and functional brain networks in 135 indigenous Tibetan highlanders. Analyses of individual HA adaptive single‐nucleotide polymorphisms (SNPs) revealed that specific SNPs selectively modulated physiological characteristics (erythrocyte level, ratio between forced expiratory volume in the first second to forced vital capacity, arterial oxygen saturation, and heart rate) and structural network centrality (the left anterior orbital gyrus) with no effects on neuropsychology or functional brain networks. Further analyses of genetic adaptive scores, which summarized the overall degree of genetic adaptation to HA, revealed significant correlations only with structural brain networks with respect to local interconnectivity of the whole networks, intermodule communication between the right frontal and parietal module and the left occipital module, nodal centrality in several frontal regions, and connectivity strength of a subnetwork predominantly involving in intramodule edges in the right temporal and occipital module. Moreover, the associations were dependent on gene loci, weight types, or topological scales. Together, these findings shed new light on genotype–phenotype interactions under HA hypoxia and have important implications for developing new strategies to optimize organism and tissue responses to chronic hypoxia induced by extreme environments or diseases.  相似文献   
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