全文获取类型
收费全文 | 1284篇 |
免费 | 59篇 |
国内免费 | 11篇 |
专业分类
耳鼻咽喉 | 25篇 |
儿科学 | 92篇 |
妇产科学 | 28篇 |
基础医学 | 91篇 |
口腔科学 | 45篇 |
临床医学 | 130篇 |
内科学 | 323篇 |
皮肤病学 | 39篇 |
神经病学 | 41篇 |
特种医学 | 53篇 |
外科学 | 339篇 |
综合类 | 11篇 |
一般理论 | 1篇 |
预防医学 | 44篇 |
眼科学 | 17篇 |
药学 | 45篇 |
肿瘤学 | 30篇 |
出版年
2023年 | 7篇 |
2022年 | 10篇 |
2021年 | 21篇 |
2020年 | 11篇 |
2019年 | 22篇 |
2018年 | 26篇 |
2017年 | 35篇 |
2016年 | 45篇 |
2015年 | 56篇 |
2014年 | 56篇 |
2013年 | 58篇 |
2012年 | 67篇 |
2011年 | 62篇 |
2010年 | 48篇 |
2009年 | 58篇 |
2008年 | 101篇 |
2007年 | 99篇 |
2006年 | 100篇 |
2005年 | 107篇 |
2004年 | 95篇 |
2003年 | 69篇 |
2002年 | 51篇 |
2001年 | 19篇 |
2000年 | 22篇 |
1999年 | 29篇 |
1998年 | 12篇 |
1997年 | 5篇 |
1996年 | 4篇 |
1995年 | 5篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1992年 | 9篇 |
1991年 | 6篇 |
1990年 | 7篇 |
1989年 | 2篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 3篇 |
1984年 | 3篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1979年 | 3篇 |
1978年 | 5篇 |
1977年 | 2篇 |
1976年 | 1篇 |
1974年 | 3篇 |
1973年 | 1篇 |
排序方式: 共有1354条查询结果,搜索用时 15 毫秒
101.
Bozkurt B Mesci L Irkec M Ozdag BB Sanal O Arslan U Ersoy F Tezcan I 《Clinical & experimental ophthalmology》2012,40(4):e156-e162
Background: Tumour necrosis factor‐alpha (TNF‐α) is an important proinflammatory cytokine driving axonal degeneration and retinal ganglion cell apoptosis in glaucoma. The aim of the study was to evaluate the association of TNF‐α ‐308 G/A and ‐238 G/A polymorphisms with primary open‐angle glaucoma (POAG). Design: A prospective, case–control study, university hospital setting. Participants: Eighty‐six POAG patients and 193 healthy unrelated controls. Methods: TNF‐α polymorphisms were screened by using direct gene sequencing. Main Outcome Measures: Frequency of TNF‐α ‐308 G/A and TNF‐α ‐238 G/A promoter polymorphisms in glaucoma and healthy subjects. Results: The frequencies of TNF‐α ‐308 GA genotype and ‘A’ allele were higher in patients with POAG (22.1% and 12.2%, respectively) in comparison with the control group (10.9% and 6%, respectively) (P = 0.046 and 0.02, respectively), with odds ratios of 2.45 (P = 0.01, 95% CI = 1.23–4.87) and 2.19 (P = 0.013, 95% CI = 1.18–4.08), respectively. Genotype distribution of the TNF‐α ‐238 variants did not yield a statistically significant difference between the two groups (P = 0.87). Conclusion: TNF‐α ‐308 G/A polymorphism seems to be associated with POAG in Turkish population. However, population‐based studies with large number of subjects and long‐term follow‐up are needed to verify the association of TNF‐α ‐308 G/A polymorphism with glaucoma susceptibility. 相似文献
102.
103.
Heavy metals in soil, vegetables and fruits in the endemic upper gastrointestinal cancer region of Turkey 总被引:10,自引:0,他引:10
Türkdoğan MK Kilicel F Kara K Tuncer I Uygan I 《Environmental toxicology and pharmacology》2003,13(3):175-179
The environmental exposure to heavy metals is a well-known risk factor for cancer. We investigated levels of seven different heavy metals, (Co, Cd, Pb, Zn, Mn, Ni and Cu) in soil, fruit and vegetable samples of Van region in Eastern Turkey where upper gastrointestinal (GI) cancers are endemic. Heavy metal contents of the samples were determined by flame atomic absorption spectrometer. Four heavy metals (Cd, Pb, Cu and Co) were present in 2- to 50-fold higher concentrations whereas zinc levels were present in 40-fold lower concentrations in soil. The fruit and vegetable samples were found to contain 3.5- to 340-fold higher amounts of the six heavy metals (Co, Cd, Pb, Mn, Ni and Cu) tested. The volcanic soil, fruit and vegetable samples contain potentially carcinogenic heavy metals in such a high levels that these elements could be related to the high prevalence of upper GI cancer rates in Van region. 相似文献
104.
105.
106.
Vogt-Koyanagi-Harada (VKH) disease is a rare inflammatory ocular disorder that is characterized by bilateral granulomatous
panuveitis, neuropathy, and aseptic meningitis, along with various extraocular manifestations. VKH disease has been reported
to be associated with various immune disorders. In this report, a case of VKH disease is presented that is associated with
mesenteric vascular disease and intestinal necrosis, with an emphasis on the fact that this is the first case documented in
the literature of both diseases occurring simultaneously. 相似文献
107.
Objective
Besides severe organ shortage, hepatitis C virus (HCV) infection is an important obstacle for kidney transplantation because of long waiting times on deceased kidney donor waiting lists. We aimed to evaluate calling number of candidates according to HCV serology.Method
A total of 404 adults on the deceased donor waiting list invited for cadaveric transplantation was evaluated. Demographic data, waiting time, calling number for transplantation, and viral serology were obtained during the 6-year period.Results
Mean waiting duration and calling number of all patients were 42.7 ± 34 months and 1.56 ± 4.37 times, respectively. Twenty-six candidates had chronic HCV infection and 12 of 26 were HCV RNA–positive. Mean waiting duration and calling number in anti-HCV–positive candidates were significantly higher compared with anti-HCV–negative candidates (85.3 ± 38.8 vs 39.8 ± 31.6 months, and 10.8 ± 10.3 vs 0.92 ± 2.6 times, respectively; P < .001). Mean waiting duration and total calling number in HCV-RNA–positive candidates were significantly higher than in HCV-RNA–negative ones (107.5 ± 7.5 vs 66.2 ± 44.8 months; P = .018; 15 ± 9.7 vs 7.3 ± 9.8 times, respectively; P = .026).Conclusions
Chronic HCV infection is an important issue leading to longer waiting time on the list. Our observation showed that waiting durations of anti-HCV–positive candidates were longer than that of negative patients, although they had more frequent opportunity for transplantation. 相似文献108.
Baysan O Kaptan K Erinç K Oztas Y Coskun T Kayir H Uzun M Uzbay T Beyan C Işik E 《The Tohoku journal of experimental medicine》2005,206(2):85-90
Although moderate alcohol consumption seems to be protective against atherosclerosis, coronary artery disease rate increases with its higher doses. Platelet aggregation is an important process which contributes to the atherosclerosis. The aim of this study was to determine whether heavy ethanol consumption stimulates or inhibits platelet aggregation. Fourteen adult male Wistar rats were used. Ethanol (7.2%, v/v) in a modified liquid diet was given to eight rats for 21 days, which mimicked characteristics similar to human chronic alcoholism. Six rats constituted the control group. Adenosine diphophate (ADP) and collagen-induced platelet aggregation was measured in whole blood. We found reduced ADP-induced mean maximal aggregation in the alcoholic rat group compared to the control group at dose of 5 microM (p < 0.005). We also found decreased platelet aggregation responses to collagen in the alcoholic group (p < 0.006 for 2 microg/ml collagen, and p < 0.05 for 5 microg/ml collagen). In conclusion, chronic heavy ethanol consumption results in the decreased platelet aggregation in a rat model of alcoholism. Therefore, increased mortality from coronary artery disease in chronic alcoholism may be explained by other factors such as dietary imbalances and coexisting conditions, which include hypertension and depression. 相似文献
109.
110.