全文获取类型
收费全文 | 986篇 |
免费 | 53篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 47篇 |
妇产科学 | 6篇 |
基础医学 | 111篇 |
口腔科学 | 16篇 |
临床医学 | 127篇 |
内科学 | 210篇 |
皮肤病学 | 21篇 |
神经病学 | 23篇 |
特种医学 | 152篇 |
外科学 | 46篇 |
综合类 | 106篇 |
预防医学 | 61篇 |
眼科学 | 3篇 |
药学 | 69篇 |
中国医学 | 4篇 |
肿瘤学 | 48篇 |
出版年
2022年 | 10篇 |
2021年 | 10篇 |
2020年 | 5篇 |
2019年 | 7篇 |
2018年 | 10篇 |
2017年 | 10篇 |
2016年 | 13篇 |
2015年 | 22篇 |
2014年 | 38篇 |
2013年 | 30篇 |
2012年 | 33篇 |
2011年 | 43篇 |
2010年 | 40篇 |
2009年 | 40篇 |
2008年 | 46篇 |
2007年 | 37篇 |
2006年 | 28篇 |
2005年 | 23篇 |
2004年 | 17篇 |
2003年 | 28篇 |
2002年 | 24篇 |
2001年 | 19篇 |
2000年 | 16篇 |
1999年 | 22篇 |
1998年 | 51篇 |
1997年 | 43篇 |
1996年 | 32篇 |
1995年 | 20篇 |
1994年 | 28篇 |
1993年 | 24篇 |
1992年 | 10篇 |
1991年 | 19篇 |
1990年 | 14篇 |
1989年 | 21篇 |
1988年 | 25篇 |
1987年 | 40篇 |
1986年 | 14篇 |
1985年 | 20篇 |
1984年 | 11篇 |
1983年 | 9篇 |
1982年 | 15篇 |
1981年 | 9篇 |
1980年 | 7篇 |
1978年 | 11篇 |
1977年 | 4篇 |
1976年 | 13篇 |
1975年 | 10篇 |
1973年 | 4篇 |
1972年 | 4篇 |
1970年 | 5篇 |
排序方式: 共有1054条查询结果,搜索用时 15 毫秒
1.
Akira Sawaki Nobumasa Mizuno Kuniyuki Takahashi Tsuneya Nakamura Masahiro Tajika Hiroki Kawai Toshifumi Isaka Hiroshi Imaoka Yasuyuki Okamoto Masatoshi Aoki Hiroyuki Inoue Ahmed AS Salem Yasushi Yatabe Kenji Yamao 《Digestive endoscopy》2006,18(1):40-44
Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed. 相似文献
2.
G F Sasso M Ceccanti E Nardi G Valicenti M A Savina N Stella F Zacco 《Panminerva medica》1989,31(1):30-33
The activity of LCAT (the controlling enzyme for cholesterol esterification in plasma) is known to be reduced in alcoholic cirrhosis, while little is known about early stage (liver steatosis) alcoholics. In this study, LCAT activity was assayed by Stokke and Norum's method, before and after a 15-day sobriety period, in liver steatosis and in cirrhosis alcoholics. Before alcohol withdrawal, LCAT activity was depressed in both groups. After the sobriety period, LCAT activity was significantly raised in liver steatosis patients, but was still lower than in controls; in cirrhosis patients, it was increased, but not significantly. According to our results, LCAT activity impairment in alcoholic liver disease is sustained by both the hypothesized mechanisms, alcohol-related metabolic disorders and lowered LCAT-enzyme production, but to different degrees, depending on the stage of the disease. In liver steatosis, metabolic disorders play a major role, as a liver-impairment-induced decrease in LCAT production seems rather unlikely, and increased LCAT activity is more likely to be sustained by metabolic normalisation than by any recovery of the damaged liver. However, the lack of improvement in about 20% of patients, and the fairly wide scattering of individual data, suggest a minor LCAT production impairment in liver steatosis too. In cirrhosis, the major role seems to be played by a permanent decrease in LCAT production, as no significant rise in LCAT activity was observed after alcohol withdrawal. However the restored LCAT activity observed in some patients could be related to improvement in the metabolic disorder, thus confirming the effectiveness of this mechnism in cirrhosis too.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
3.
Coronary artery bypass grafts: visualization with MR imaging 总被引:1,自引:0,他引:1
4.
5.
6.
7.
N V Mironets R V Savina I S Kucherov V V Solntseva N V Martyshchenko 《Kosmicheskaia biologiia i aviakosmicheskaia meditsina》1988,22(1):63-66
The purpose of the study was to identify maxim allowable concentrations of urea in reclaimed potable water. The urea concentration equal to 80 mg/l is the threshold dose influencing the taste and flavor of water. Urea is a low toxicity substance (LD50 = 14,300 mg/kg), the effect of which is not cumulative. However, when used in high doses it affects bioenergetic and cholinergic processes and causes changes in ECG, higher nervous activity and visceral structure. It has been shown that when applied to warm-blooded animals the acting dose of urea is 14.3 and 1.43 mg/kg (1/1000 and 1/10000 LD50), the threshold dose is 0.72 mg/kg (1/20000 LD50), and the ineffective dose is 0.36 mg/kg (1/40000 LD50) which amounts to the concentration of 10 mg/l. In terms of toxic effects the dose equal to 10 mg/l is taken to be the maximally allowable concentration of urea. It is recommended to use the Laham biotest for measuring urea in water. 相似文献
8.
9.
10.
Evaluation of a new enzyme-linked immunosorbent assay test for rotavirus antigen in faeces 总被引:6,自引:0,他引:6
下载免费PDF全文
![点击此处可从《Journal of clinical pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
A new commercial test for the diagnosis of rotavirus gastroenteritis was assessed. With some modifications it compared favourably with electron microscopy and immunofluorescence. 相似文献