全文获取类型
收费全文 | 4666篇 |
免费 | 259篇 |
国内免费 | 20篇 |
专业分类
耳鼻咽喉 | 36篇 |
儿科学 | 129篇 |
妇产科学 | 83篇 |
基础医学 | 693篇 |
口腔科学 | 148篇 |
临床医学 | 357篇 |
内科学 | 1168篇 |
皮肤病学 | 110篇 |
神经病学 | 380篇 |
特种医学 | 68篇 |
外科学 | 518篇 |
综合类 | 31篇 |
一般理论 | 1篇 |
预防医学 | 164篇 |
眼科学 | 207篇 |
药学 | 428篇 |
中国医学 | 35篇 |
肿瘤学 | 389篇 |
出版年
2023年 | 49篇 |
2022年 | 76篇 |
2021年 | 115篇 |
2020年 | 49篇 |
2019年 | 86篇 |
2018年 | 105篇 |
2017年 | 78篇 |
2016年 | 108篇 |
2015年 | 100篇 |
2014年 | 121篇 |
2013年 | 167篇 |
2012年 | 251篇 |
2011年 | 312篇 |
2010年 | 174篇 |
2009年 | 158篇 |
2008年 | 294篇 |
2007年 | 314篇 |
2006年 | 282篇 |
2005年 | 307篇 |
2004年 | 289篇 |
2003年 | 264篇 |
2002年 | 283篇 |
2001年 | 84篇 |
2000年 | 88篇 |
1999年 | 73篇 |
1998年 | 52篇 |
1997年 | 38篇 |
1996年 | 41篇 |
1995年 | 28篇 |
1994年 | 30篇 |
1993年 | 18篇 |
1992年 | 47篇 |
1991年 | 42篇 |
1990年 | 47篇 |
1989年 | 35篇 |
1988年 | 23篇 |
1987年 | 23篇 |
1986年 | 25篇 |
1985年 | 31篇 |
1984年 | 31篇 |
1983年 | 15篇 |
1982年 | 12篇 |
1981年 | 14篇 |
1980年 | 18篇 |
1979年 | 23篇 |
1978年 | 18篇 |
1974年 | 16篇 |
1972年 | 12篇 |
1971年 | 11篇 |
1970年 | 11篇 |
排序方式: 共有4945条查询结果,搜索用时 0 毫秒
71.
72.
73.
74.
Moriya T Ohno S Hirasawa Y Tanaka K Fujita Y 《Diabetes research and clinical practice》2008,80(3):424-431
Mesangial expansion and glomerular basement membrane (GBM) thickening did not correlate with urinary albumin excretion (UAE) in type 2 diabetic patients in our previous studies; therefore, it was necessary to elucidate more detailed ultrastructural changes in the early stages of diabetic nephropathy (DN) in type 2 diabetic patients. The quick-freezing and deep-etching (QF–DE) method allows us to examine three-dimensional ultrastructures of human renal glomeruli in vivo at high resolution. The QF–DE method was applied to six type 2 diabetic patients without definable renal diseases other than DN. Four patients were normoalbuminuric (NA) and the other two were microalbuminuria (MA). Three control specimens were the normal parts from nephrectomies due to renal cell carcinomas. Electron microscopic morphometric analyses provided quantitative glomerular structural changes. Replica membranes were prepared by the QF–DE method, and diameters of mesh structures at the GBM and mesangial matrix (MM) were measured on electron micrographs as previously described. By the QF–DE method, both the GBM middle layer and MM were composed of polygonal meshwork structures. The mesh pores of the GBM and MM were more enlarged and irregular in shape in NA diabetic patients than those of the controls, and these ultrastructural changes became more obvious in MA patients. The mesh diameters of the GBM and MM in the diabetic patients were also larger than those of the controls. Such a mesh diameter of the GBM was well correlated with the amount of UAE, while the mesh diameter of MM showed a slight correlation with UAE. Although there were small number of subjects in the present study, the detailed ultrastructural changes in NA and MA type 2 diabetic patients, which had not been disclosed by conventional electron microscopy, were revealed by the QF–DE method. Increased mesh diameters of GBM might be related with the increase of UAE. 相似文献
75.
Ohfuji Satoko Matsuura Tomoka Tamori Akihiro Kubo Shoji Sasaki Satoshi Kondo Kyoko Ito Kazuya Fukushima Wakaba 《Digestive diseases and sciences》2021,66(6):2118-2128
Digestive Diseases and Sciences - Hepatocellular carcinoma develops in some patients with hepatitis C virus (HCV), even after achieving sustained virological response (SVR). We examined factors... 相似文献
76.
W F Shen G S Roubin K Hirasawa R F Uren B F Hutton P J Harris P J Fletcher D T Kelly 《The American journal of cardiology》1984,54(6):605-609
To examine the effects of nifedipine on the left ventricular (LV) functional response to isometric exercise in patients with aortic regurgitation (AR), 20 patients with isolated, moderate to severe AR performed 3 minutes of handgrip exercise at 33% of their maximal voluntary contraction, before and after administration of 20 mg of sublingual nifedipine. Although handgrip exercise produced similar increases in heart rate and systolic blood pressure before and after nifedipine treatment, heart rate was higher and systolic blood pressure lower with handgrip exercise during nifedipine treatment. LV end-diastolic volume index was not different during the control period and nifedipine handgrip exercise, but the increase in end-systolic volume index was smaller and the ejection fraction was higher during nifedipine handgrip exercise. Nifedipine reduces afterload and ameliorates handgrip exercise-induced LV dysfunction in patients with AR. 相似文献
77.
Shinichi Niwano Hidehira Fukaya Masaru Yuge Ryuta Imaki Shouji Hirasawa Takeshi Sasaki Yoshihiro Yumoto Takayuki Inomata Tohru Izumi 《Circulation journal》2008,72(2):268-273
BACKGROUND: Ventricular tachyarrhythmias (VT/VF) are 1 of the most important factors determining the prognosis of patients with heart failure (HF). Although priority is given to implantable cardioverter defibrillator (ICD) therapy for the prevention of sudden cardiac death, electrophysiologic-study (EPS)-guided preventive therapy could be important for reducing the number of cardiac events. METHODS AND RESULTS: Of 864 patients with a history of HF, an EPS was performed in 168 and 121 had inducible VT/VF. Under the basic therapy of an ICD, additional catheter ablation was attempted for 95 of 124 monomorphic VT foci in 74 patients, and 78 of the VT were successfully ablated. The prognoses were compared among 5 patient groups with different results for the EPS and catheter ablation: (1) success group (n=43), (2) failure group (n=15), (3) not attempted group (n=16), (4) VF group (n=47), and (5) no inducible VT/VF group. During a follow-up period of 31+/-22 months, the incidence of VT/VF was lower in the success and no inducible VT/VF groups than in the other groups (p=0.0018), although a significant difference was not observed for the total deaths. CONCLUSION: EPS-guided preventive therapy using an ICD and catheter ablation can be useful, at least for the reduction of arrhythmic events in patients with HF. 相似文献
78.
Although Helicobacter pylori have been identified in the liver, the role of Helicobacter sp. in human liver diseases remains unclear. This study explored whether H. pylori were internalized and could persist in hepatocytes. The majority of an inoculum of H. pylori (1 x 10(7) colony forming units) adhered to hepatocytes. Using the gentamicin invasion assay we found that approximately 2% were internalized and persisted following passage for more than 2 months. Electron microscopy confirmed the presence of intracellular Helicobacter. The number of adherent or internalized H. pylori was significantly greater with hepatocytes than with gastric epithelial cells (P < 0.05) and was also dependent on cag pathogenicity island (PAI), VacA, OipA, or BabA status. Transmission electron microscopy was used to confirm adherence and invasion of H. pylori into hepatocytes. Internalization of H. pylori was inhibited by antibodies to beta1-integrin receptors, genistein, and cytochalasin D (P < 0.05) consistent with beta1-integrin acting as a surface receptor with additional requirements for tyrosine kinase phosphorylation and actin polymerization. In summary, H. pylori both adhered to and invaded into hepatocytes in vitro, depending on the virulent factors, and persisted within hepatocytes during subcultures. beta1-integrin is likely a receptor involved in internalization of H. pylori into hepatocytes. 相似文献
79.
80.