首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   246535篇
  免费   18724篇
  国内免费   7819篇
耳鼻咽喉   1402篇
儿科学   8878篇
妇产科学   1849篇
基础医学   21649篇
口腔科学   3655篇
临床医学   26484篇
内科学   60239篇
皮肤病学   2830篇
神经病学   27390篇
特种医学   7310篇
外国民族医学   8篇
外科学   21453篇
综合类   33488篇
现状与发展   33篇
一般理论   9篇
预防医学   20666篇
眼科学   2430篇
药学   17685篇
  209篇
中国医学   10631篇
肿瘤学   4780篇
  2024年   748篇
  2023年   5016篇
  2022年   9008篇
  2021年   12793篇
  2020年   11971篇
  2019年   9214篇
  2018年   9157篇
  2017年   9051篇
  2016年   9461篇
  2015年   9131篇
  2014年   17277篇
  2013年   18743篇
  2012年   14236篇
  2011年   15365篇
  2010年   12160篇
  2009年   11711篇
  2008年   11688篇
  2007年   11343篇
  2006年   10147篇
  2005年   8426篇
  2004年   7165篇
  2003年   6140篇
  2002年   5188篇
  2001年   4498篇
  2000年   3738篇
  1999年   3220篇
  1998年   3056篇
  1997年   2703篇
  1996年   2432篇
  1995年   2169篇
  1994年   1988篇
  1993年   1717篇
  1992年   1663篇
  1991年   1443篇
  1990年   1169篇
  1989年   998篇
  1988年   935篇
  1987年   838篇
  1986年   756篇
  1985年   886篇
  1984年   729篇
  1983年   460篇
  1982年   552篇
  1981年   456篇
  1980年   342篇
  1979年   296篇
  1978年   233篇
  1977年   196篇
  1976年   164篇
  1975年   65篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
43.
44.

Background and aims

It is not known whether non alcoholic fatty liver disease (NAFLD) is a risk factor for diabetes in non obese, non centrally-obese subjects. Our aim was to investigate relationships between fatty liver, insulin resistance and a biomarker score for liver fibrosis with incident diabetes at follow up, in subjects who were neither obese nor centrally-obese.

Methods and results

As many as 70,303 subjects with a body mass index (BMI) < 25 kg/m2 and without diabetes were followed up for a maximum of 7.9 years. At baseline, fatty liver was identified by liver ultrasound, insulin resistance (IR) by homeostatic model assessment of insulin resistance (HOMA-IR) ≥2.0, and central obesity by waist circumference (waist circumference ≥90 cm (men) and ≥85 cm (women). The Fibrosis-4 (FIB-4 score) was used to estimate extent of liver fibrosis. Cox proportional hazards models adjusted for confounders were used to estimate hazard ratios (aHRs) for incident diabetes. As many as 852 incident cases of diabetes occurred during follow up (median [IQR] 3.71 [2.03] years). Mean ± SD BMI was 22.8 ± 1.8 and 21.7 ± 2.0 kg/m2 in subjects with and without diabetes at follow up. In subjects without central obesity and with fatty liver, aHRs (95% CI) for incident diabetes at follow up were 2.17 (1.56, 3.03) for men, and 2.86 (1.50,5.46) for women. Similar aHRs for incident diabetes occurred with fatty liver, IR and the highest quartile of FIB-4 combined, in men; and there was a non significant trend toward increased risk in women.

Conclusions

In normal weight, non-centrally obese subjects NAFLD is an independent risk factor for incident diabetes.  相似文献   
45.
Background and aimsCoronary artery disease (CAD) is the principal cause of death in individuals with non-alcoholic fatty liver disease (NAFLD). The aim of this study was to use genetic epidemiology to study the association between de novo lipogenesis (DNL), one of the major pathways leading to NAFLD, and CAD risk.Methods and resultsDNL susceptibility genes were used as instruments and selected using three approaches: 1) genes that are associated with both high serum triglycerides and low sex hormone-binding globulin, both downstream consequences of DNL (unbiased approach), 2) genes that have a known role in DNL (biased approach), and 3) genes that have been associated with serum fatty acids, used as a proxy of DNL. Gene-CAD effect estimates were retrieved from the meta-analysis of CARDIoGRAM and the UK Biobank (~76014 cases and ~264785 controls). Effect estimates were clustered using a fixed-effects meta-analysis. Twenty-two DNL susceptibility genes were identified by the unbiased approach, nine genes by the biased approach and seven genes were associated with plasma fatty acids. Clustering of genes selected in the unbiased and biased approach showed a statistically significant association with CAD (OR:1.016, 95%CI:1.012; 1.020 and OR:1.013, 95%CI:1.007; 1.020, respectively), while clustering of fatty acid genes did not (OR:1.004, 95%CI:0.996–1.011). Subsequent exclusion of potential influential outliers did reveal a statistically significant association (OR:1.009, 95%CI:1.000; 1.018).ConclusionsDNL susceptibility genes are associated with an increased risk of CAD. These findings suggest that DNL may be involved in the pathogenesis of CAD and favor further development of strategies that target NAFLD through DNL.  相似文献   
46.
47.
The main goal in the management of patients with vesicoureteral reflux (VUR) is the preservation of kidney function by minimizing the risk of pyelonephritis. By defining and analyzing the risk factors for each patient depending on age, sex, grade of reflux, lower urinary tract dysfunction, anatomic abnormalities, and kidney status, it is possible to identify those patients with a potential risk of upper urinary tract infection and resulting renal scarring. This paper gives a brief overview of the European Association of Urology guidelines for the management and treatment of VUR in children. These guidelines are based on the best currently available knowledge and evidence.  相似文献   
48.
49.
目的了解长春西部地区过敏原特异性IgE分布情况。方法应用免疫印迹法检测1 258例患者的19种吸入性及食物性过敏原特异性IgE抗体,统计过敏原结果及种类。结果 1 258例患者,检出至少一种特异性IgE阳性率为34.0%。男性阳性率为33.5%;女性阳性率为34.5%。男女间阳性率差异无统计学意义(P> 0.05)。吸入性过敏原阳性率由高到低依次为:普通豚草14.2%、艾蒿11.4%、屋尘螨/粉尘螨8.1%、猫毛3.8%、狗上皮2.4%、柳树/杨树/榆树2.1%,屋尘1.6%、蟑螂1.6%、点青霉/分枝孢霉/烟曲霉/交链孢霉1.2%、葎草1.1%。食物性过敏原阳性率由高到低依次为:鸡蛋白2.9%、鳕鱼/龙虾/扇贝2.7%、牛奶2.3%、黄豆1.9%、蟹1.5%、虾1.3%、牛肉1.2%、花生1.0%、羊肉0.8%。混合过敏达到了相当高的比例。结论长春西部地区吸入性过敏原以普通豚草、艾蒿和屋尘螨/粉尘螨为主;食物性过敏原以鸡蛋白、鳕鱼/龙虾/扇贝、牛奶为主,明确过敏原,对过敏性患者的预防和治疗有重大意义。  相似文献   
50.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号