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排序方式: 共有849条查询结果,搜索用时 15 毫秒
841.
842.
Background Systemic inflammation has been linked with reduced survival in cancer, however, the role of the host cytokine genotype versus tumour phenotype in the generation of this response is not clearly established. This study examined the relationship between cytokine polymorphisms (IL-1β 511, IL-6 174, IL-10 1082, TNFα 308 and LTα +252) and serum cytokine concentrations, serum CRP concentration and survival duration in patients with gastro-oesophageal malignancy. Methods Two hundred and three newly diagnosed patients with gastric or oesophageal cancer had serum CRP and cytokine concentrations determined by ELISA. SNP genotyping was performed by Taqman allelic discrimination genotyping and compared with the genotype observed in 266 healthy volunteers. Clinico-pathological information was collected prospectively and survival duration was recorded. Results Distribution of the cytokine genotypes was similar between patients and controls. The IL-6 174 CC and IL-10 1082 GG genotypes were associated with elevated serum CRP (P = .03, P = .01, respectively; Mann–Whitney U test) and sTNF-R (P = .015, P = .02) concentrations. These genotypes were also associated with reduced survival duration (P = .01, P = .047; log-rank test). TNFα AA genotype was also associated with reduced survival duration on univariate (P = .032) and multivariate analysis (P = .006, multivariate model), but not with inflammatory markers. No other cytokine polymorphisms were associated with systemic inflammatory markers or prognosis. Conclusions There is a pro-inflammatory cytokine haplotype (IL-6 CC, IL-10 GG, TNFα AA) that is associated with adverse prognosis that may act, at least in part, through an inflammatory mediated mechanism. Determining patients’ cytokine haplotype may improve prognostication and allow stratification for intervention studies.  相似文献   
843.
We examined associations between polymorphisms in genes related to estrogen metabolism (CYP1B1 codon 432G → C rs#1056836, CYP1B1 codon 453A → G rs#1800440, COMT codon 158G → A rs#4680) and biosynthesis (CYP17 T → C promoter rs#743572, CYP19 exon 4 TTTA repeat) and urinary estrogen metabolites (2-hydroxyestrogens (2-OHE), 16α-hydroxyestrone (16α-OHE1), and their ratio) in a pilot study of 64 pre- and post-menopausal women with a family history of breast cancer. Women were participants in the Metropolitan New York Registry of Breast Cancer Families, one of six international sites of the National Cancer Institute’s Breast Cancer Family Registry. We used linear regression to examine the effects of genetic variants on log-transformed urinary estrogen metabolites. After adjusting for menopausal status, BMI, and age, carriers of the CYP1B1 codon 453G variant allele had 31.0% lower levels of 2-OHE (P-value = 0.05) and 40.2% lower levels of 16α-OHE1 (P = 0.01). Results were similar after restricting the analyses to pre-menopausal women (n = 41). Consistent with other studies, among pre-menopausal women, carriers of the COMT codon 158A variant allele had increased 2-OHE levels (P = 0.03) and an increased 2-OHE/16α-OHE1 ratio (P = 0.04); carriers of the CYP17 C promoter variant allele had increased 2-OHE levels (P = 0.08). To our knowledge this is the first report showing associations between the CYP1B1 codon 453G variant allele and urinary 2-OHE and 16α-OHE1 metabolites. Further larger studies should be conducted to confirm these results. Future identification of individuals with genetic polymorphisms that affect estrogen metabolism and biosynthesis may help characterize women at higher breast cancer risk and could guide breast cancer prevention strategies for those individuals.  相似文献   
844.
A multigenic approach to predict breast cancer risk   总被引:2,自引:0,他引:2  
In the biology of complex disorders, such as breast cancer, interactions among genetic factors may play an important role and theoretical considerations suggest that gene-gene interactions are quite common in such diseases. In this case-control study with 500 breast cancer patients and 500 population-based healthy sex- and age-matched control subjects, we applied a multigenic approach to examine the associations with breast cancer risk of a comprehensive panel of 16 selected polymorphisms in a variety of pathways using classification tree analysis (CART). Overall, 79.6% of all breast cancer patients and 80.6% of all control subjects were correctly classified on the basis of their individual genetic profile by the classification procedure. CART analysis of the data identified the heterozygous vascular endothelial growth factor (VEGF) and matrix metalloproteinase 3 (MMP3) genotype and homozygous cyclooxygenase-2 (PTGS2) mutant as the initial splits, indicating that these genotypes exert the greatest impact on the classification process. Breast cancer patients were primarily indicated by 30 distinct genetic profiles. The odds ratio of these genetic risk profiles for breast cancer was 16.12 (95% confidence interval 11.09-23.49). Five genetic profiles formed homogenous breast cancer subgroups and represented highest risk genetic profiles. This is the first comprehensive study to use a multigenic analysis for breast cancer and the data suggest that individuals with distinct genetic profiles are at an increased risk for breast cancer, confirming the importance of taking a multigenic approach for risk assessment.  相似文献   
845.
目的了解白细胞介素-6(IL-6)基因-597G/A及-572C/G多态性对冠心病(CHD)发病易感性的影响及其影响机制。方法 应用聚合酶链反应.限制性片段长度多态性(PCR-RFLP)分析方法,测定245例CHD患者和260例正常对照者的IL-6基因型,探讨其与CHD的相关关系;观察基因型对血清IL-6水平的影响,并采用logistic回归分析法了解基因型与CHD其他危险因素间的相互作用。结果 两组研究对象中-597位点均仅发现GG基因型。-572C/G基因型和等位基因频率在两组间存在明显统计学差异(P均〈0.01),CHD组GG基因型和G等位基因频率均显著高于对照组(P均〈0.01);CG、GG基因型人群患CHD的风险分别为CC基因型人群的1.46倍(95%CI:1.01~2.10,P〈0.05)和5.19倍(95%CI:1.69~15.89,P〈0.01);不同基因型患者间血清IL-6水平无统计学差异(P〉0.05);-572C/G基因型与总胆固醇、甘油三酯间存在一定的交互作用,OR值分别为1.76(95%CI:1.05~3.16,P〈0.05)、2.51(95%CI:1.04~6.45,P〈0.05)。结论 IL-6基因-597G/A多态性可能与中国汉族人群CHD发病易感性无关,而-572C/G多态性可能是该人群CHD发病的易感基因之一,其可能通过对组织IL-6水平的影响及与血脂的协同作用参与CHD的发生。  相似文献   
846.
Vesico-ureteral reflux (VUR) is the most common inherited disorder of the lower urinary tract. Children with VUR are at risk for ongoing renal damage with subsequent infections. IL8 is an important inflammatory mediator which can be produced by epithelial cells of the renal tract in response to a variety of inflammatory stimuli. High serum concentrations of IL-8 have been reported in patients with chronic renal failure. Elevated IL-8 levels have been reported in the urine of patients with VUR and renal parenchymal scarring (RPS). More recently it was reported that urine IL-8 levels remain elevated in infants with VUR even in the absence of a urinary tract infection (UTI). Increased IL-8 expression has been shown to be associated with polymorphism at position -251 (rs4073) of the IL-8 promoter. The aim of this study was to examine the association of IL-8 gene polymorphism with familial VUR in a cohort of 219 siblings from 109 families affected with VUR, the largest such cohort tested to date. RPS was assessed using dimercaptosuccinic acid scintigraphy. Genotyping was performed in 219 siblings with VUR (157 without RPS, 62 with RPS) and 292 controls for the position -251 of IL-8 gene by polymerase chain reaction with tetra primers and gel analysis. Genotype was compared using the chi square test. Statistical significance was taken as a value of P < 0.05. There were no significant differences in IL-8 -251 genotype frequency between VUR patients and controls. Similarly, gender, severity of VUR and renal parenchymal scarring had no effect on IL-8 -251 genotype frequency. Although IL-8 urinary levels have been reported to be elevated in VUR, our data indicate that IL-8 gene is not involved in the pathogenesis of familial VUR or reflux nephropathy.  相似文献   
847.
It is well established that genetic factors play a major role in the pathogenesis of osteoporosis. Previous reports have suggested that vitamin D receptor (VDR) gene polymorphisms, particularly the BB, tt and AA genotypes, are associated with low bone mineral density (BMD). If these VDR genotypes are indeed an important determinant of BMD, then a population of related osteoporotic individuals (mother–daughter or sister–sister relationship) should have a high prevalence of the BB, tt or AA VDR genotypes. To test this hypothesis we determined the VDR genotypes in 26 osteoporotic persons (age 44.3 ± 12.7 years, mean ± SD) belonging to 12 families. Furthermore, for comparison with existing studies, we applied the VDR genotype analysis in a population of 53 unrelated healthy subjects (age 45.2 ± 9.8 years, mean ± SD) and 59 unrelated osteoporotic subjects (age 52.1 ± 9.0 years, mean ± SD). The menopausal status of the healthy and osteoporotic populations was pre-, peri- and mostly early postmenopausal. The proportions of the three genotypes, BB, tt and AA, within the 12 osteoporotic families were 15%, 12% and 27%, respectively, whereas the proportions of the other three homozygous genotypes (bb, TT, aa) were 50%, 50% and 23%. The distribution of the BB, tt and AA genotypes in the normal population was 21%, 21% and 36%, respectively (vs bb, TT, aa: 36%, 38%, 21%), whereas in the osteoporotic population it was 24%, 20% and 34% (vs bb, TT, aa: 27%, 34%, 14%). Our data indicate that there is not a statistically significant (p>0.05) difference in the VDR genotype frequencies within osteoporotic families as compared with the same genotypes in the population of unrelated normal or osteoporotic subjects. VDR genotype analysis showed no significant relation between VDR polymorphisms and BMD or Z-score values at the lumbar spine. This study demonstrates the lack of a heritability pattern between the BB, tt and AA genotypes and low BMD. Received: 29 October 1998 / Accepted: 19 April 1999  相似文献   
848.
目的新近的研究提示CD40/CD40L信号途径对急性冠状动脉综合征的发病及预后均具有一定影响。本研究旨在探讨CD40L G基因单核苷酸多态性与急性冠状动脉综合征患者冠状动脉病变程度间的关系。方法搜集2008年8月至2010年8月间在北京安贞医院抢救中心确诊为急性冠状动脉综合征的患者共482例,总结分析其临床特征、相关危险因素及血清单核细胞和血小板表达CD40水平以及CD40L G基因单核苷酸多态性对冠状动脉病变程度的影响。结果 (1)6.8%(n=33)的急性冠状动脉综合征患者未检测到血清sCD40L(<95 ng/L),449例患者平均血清sCD40L为296±25 ng/L,sCD40L平均水平男性为309 ng/L,女性为195 ng/L,男性高于女性(P<0.001),sCD40L水平随着冠状动脉病变程度加重而升高(P<0.001)。(2)不同基因型间血清sCD40L水平与冠状动脉评分存在显著性差异(P<0.001),趋势具有统计学意义。其中以GG基因型的sCD40L水平最高,为409ng/L,冠状动脉病变程度最严重(P<0.001)。(3)多因素分析显示,在矫正年龄、性别及高血脂、高血压、糖尿病等危险因素后,CD40L G基因多态性与冠状动脉病变程度密切相关,它们的OR值分别为1.00、1.32、3.41(P≤0.001)。结论急性冠状动脉综合征患者血清sCD40L水平及CD40L G基因多态性与冠状动脉病变程度密切相关,在急性冠状动脉综合征临床危险分层中,血清sCD40L水平及CD40L G基因多态性是一个不容忽视的方面。  相似文献   
849.
《Human immunology》2023,84(2):80-88
Human Mannose-binding lectin (MBL) is a protein encoded by MBL2 gene involved in the activation of the lectin-complement pathway. Several studies emphasized the role of MBL2 gene in several infectious diseases’ susceptibility, including HIV-1 infection. We aim to investigate the impact of 10 MBL2 gene polymorphisms located in the promoter, 5′UTR and exon 1 regions on HIV-1 physiopathology. The polymorphisms genotyping of 400 individuals, which 200 were HIV-1 positive patients and 200 were controls, was performed by PCR-sequencing. Our results showed that rs503037 and rs1800451 polymorphisms are associated with a high risk of HIV-1 infection susceptibility while rs7096206 and rs11003123 showed a protective effect. A significant association between haplotype CGA and HIV-1 infection susceptibility was also found in the exon 1 region. Moreover, rs11003124, rs7084554, rs36014597 and rs11003123 polymorphisms revealed an association with treatment response outcome as measured by RNA viral load. This study highlights the importance of MBL2 polymorphisms in the modulation of HIV-1 infection susceptibility and the contribution to treatment response outcomes among Moroccan subjects.  相似文献   
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