全文获取类型
收费全文 | 3114篇 |
免费 | 187篇 |
国内免费 | 19篇 |
专业分类
耳鼻咽喉 | 20篇 |
儿科学 | 117篇 |
妇产科学 | 48篇 |
基础医学 | 329篇 |
口腔科学 | 9篇 |
临床医学 | 426篇 |
内科学 | 526篇 |
皮肤病学 | 14篇 |
神经病学 | 307篇 |
特种医学 | 25篇 |
外科学 | 317篇 |
综合类 | 328篇 |
一般理论 | 4篇 |
预防医学 | 424篇 |
眼科学 | 48篇 |
药学 | 168篇 |
中国医学 | 1篇 |
肿瘤学 | 209篇 |
出版年
2024年 | 3篇 |
2023年 | 26篇 |
2022年 | 47篇 |
2021年 | 86篇 |
2020年 | 58篇 |
2019年 | 99篇 |
2018年 | 109篇 |
2017年 | 68篇 |
2016年 | 99篇 |
2015年 | 74篇 |
2014年 | 101篇 |
2013年 | 141篇 |
2012年 | 283篇 |
2011年 | 311篇 |
2010年 | 144篇 |
2009年 | 113篇 |
2008年 | 216篇 |
2007年 | 246篇 |
2006年 | 240篇 |
2005年 | 222篇 |
2004年 | 129篇 |
2003年 | 128篇 |
2002年 | 133篇 |
2001年 | 15篇 |
2000年 | 16篇 |
1999年 | 11篇 |
1998年 | 26篇 |
1997年 | 6篇 |
1996年 | 12篇 |
1995年 | 13篇 |
1994年 | 12篇 |
1993年 | 12篇 |
1992年 | 11篇 |
1991年 | 8篇 |
1990年 | 6篇 |
1989年 | 5篇 |
1988年 | 6篇 |
1987年 | 8篇 |
1986年 | 5篇 |
1984年 | 8篇 |
1983年 | 5篇 |
1982年 | 7篇 |
1981年 | 8篇 |
1980年 | 7篇 |
1975年 | 4篇 |
1974年 | 5篇 |
1973年 | 3篇 |
1972年 | 3篇 |
1970年 | 4篇 |
1968年 | 4篇 |
排序方式: 共有3320条查询结果,搜索用时 0 毫秒
1.
Bridget A. Bagert 《Current neurology and neuroscience reports》2009,9(5):405-410
Recent seroepidemiologic and pathologic evidence suggests that prior infection with Epstein-Barr virus (EBV) may be necessary
for the development of multiple sclerosis (MS). EBV infects more than 90% of all humans, most of whom remain healthy. In contrast,
99% of MS patients have evidence of prior infection with EBV. EBV infects resting B lymphocytes, immortalizing them into long-lived
memory B cells that survive largely undetected by the immune system in the peripheral circulation. MS patients show elevated
titers to EBV years before developing any neurologic symptoms. Postmortem pathologic analysis of brains of patients with MS
has revealed diffuse EBV-associated B-cell dysregulation in all forms of MS. Theories of pathogenesis of EBV in MS include
antigenic mimicry, immortalization of B-cell clones, and cytotoxic T-cell dysfunction against virally infected B cells. This
article reviews the existing evidence of the relationship between EBV and MS and considers the therapeutic implication of
this evidence. 相似文献
2.
3.
4.
5.
Seronegative hepatitis is a common cause of acute liver failure (ALF) requiring liver transplantation. The primary aim of this study was to examine outcomes following transplantation in this group and to identify factors associated with early (<2 months) mortality. Patients studied were 110 consecutive cases of seronegative ALF transplanted at the Queen Elizabeth Hospital, Birmingham, between January 1992 and January 2004. Univariate analysis of 44 pretransplantation recipient, donor, and operative variables was performed initially to identify factors associated with early posttransplantation mortality. Variables identified as significant or approaching significance were analyzed using stepwise multiple logistic regression analysis. Survival following transplantation for seronegative hepatitis was 83%, 81%, and 73% at 2, 12, and 60 months, respectively. The majority (71%) of deaths occurred within the 1st 2 months and sepsis / multiorgan dysfunction was the most common cause of early death. Univariate analysis revealed 9 variables predicting early death. Subsequent multivariate analysis identified high donor body mass index (BMI; a possible surrogate marker for hepatic steatosis) as the most important predictor of early death (P = .009; odds ratio, 1.2; 95% confidence interval, 1.0-1.3). Recipient age >50 (P = .015; odds ratio, 4.2; 95% confidence interval, 1.3-14.1) and non-Caucasian recipient ethnicity (P = .015; odds ratio, 4.9; 95% confidence interval, 1.2-19.2) were other variables associated with early death on multivariate analysis. This study specifically examined factors that determine the early outcome of transplanted seronegative ALF patients. In conclusion, we found that donor and recipient factors identify patients who have a high chance of early death after transplantation. 相似文献
6.
7.
Kilpatrick David C.; Bevan Bridget H.; Liston William A. 《Human reproduction (Oxford, England)》1995,10(9):2501-2505
The distribution of mannan binding protein (MBP) in blood donorsera was determined by enzyme-linked immunosorbent assay toestablish normal concentrations. Abnormally low MBP concentrationswere found in 16% (21 out of 135) of female partners and 14%(15 out of 108) of male partners of couples experiencing recurrentmiscarriage, compared with <5% of obstetrically normal controls(P < 0.005). This relationship was even stronger (9.5 versus1.0%) and more significant (P < 0.002) when only subjectspresumed to be homozygous for the mutant allele responsiblefor MBP deficiency were considered. By immunohistochemistry,MBP could be demonstrated in first trimester placenta. We suggestthat low concentrations of MBP within the feto-placental unitincrease susceptibility to fetal loss, possibly via an infection-inducedplacental cytokine imbalance. 相似文献
8.
9.
10.
Heritability and Expression of C-Reactive Protein in Type 2 Diabetes in the Diabetes Heart Study 总被引:1,自引:0,他引:1
Leslie A. Lange Kathryn Burdon † Carl D. Langefeld Yongmei Liu Stephanie R. Beck Stephen S. Rich Barry I. Freedman K. Bridget Brosnihan David M. Herrington Lynne E. Wagenknecht Donald W. Bowden 《Annals of human genetics》2006,70(6):717-725
Elevated C-reactive protein (CRP) levels are associated with both prevalent and incident cardiovascular disease. In this study, familial aggregation was estimated, and we tested for association between serum CRP levels and polymorphisms within the CRP and APOE genes in sib-ships with type 2 diabetes mellitus, a population at increased risk for cardiovascular disease. CRP levels were determined in 461 diabetes-affected subjects from 224 sibships from the Diabetes Heart Study (DHS). Heritability estimates of CRP levels were obtained using variance component models. Genetic influence on serum CRP levels by single nucleotide polymorphisms (SNPs) in the CRP and APOE genes was evaluated by association analysis using mixed models. Subjects were Caucasian American (84%) and African-American (16%), 53% female, and had an average age of 62.2 ± 9.2 years. The median CRP level was 3.3 mg/L (range 0 to 59.3 mg/L), and estimated heritability for CRP was approximately 40%. Estimates of heritability were significantly greater than zero (P < 0.0001) and relatively constant, despite adjustments for important modifiers (age, sex, ethnicity, diabetes duration, statin-use and anti-inflammatory use) of CRP. There was no significant evidence for association of CRP levels with CRP gene SNPs; however, consistent with previous reports, there was significant evidence of association of CRP levels with polymorphisms within the APOE gene. These data indicate CRP levels are significantly influenced by genetic (and/or environmental) factors that are shared within DHS families. While the APOE locus shows evidence of contributing to CRP levels, no evidence of CRP gene polymorphism association with CRP levels was observed. 相似文献