全文获取类型
收费全文 | 25386篇 |
免费 | 1533篇 |
国内免费 | 175篇 |
专业分类
耳鼻咽喉 | 321篇 |
儿科学 | 697篇 |
妇产科学 | 846篇 |
基础医学 | 2756篇 |
口腔科学 | 758篇 |
临床医学 | 2055篇 |
内科学 | 4957篇 |
皮肤病学 | 580篇 |
神经病学 | 1218篇 |
特种医学 | 953篇 |
外国民族医学 | 15篇 |
外科学 | 4341篇 |
综合类 | 633篇 |
现状与发展 | 2篇 |
一般理论 | 12篇 |
预防医学 | 2291篇 |
眼科学 | 677篇 |
药学 | 2332篇 |
中国医学 | 185篇 |
肿瘤学 | 1465篇 |
出版年
2023年 | 260篇 |
2022年 | 870篇 |
2021年 | 1338篇 |
2020年 | 738篇 |
2019年 | 934篇 |
2018年 | 1260篇 |
2017年 | 760篇 |
2016年 | 801篇 |
2015年 | 780篇 |
2014年 | 1054篇 |
2013年 | 1311篇 |
2012年 | 1825篇 |
2011年 | 1947篇 |
2010年 | 1125篇 |
2009年 | 830篇 |
2008年 | 1135篇 |
2007年 | 1183篇 |
2006年 | 1105篇 |
2005年 | 1042篇 |
2004年 | 910篇 |
2003年 | 863篇 |
2002年 | 820篇 |
2001年 | 322篇 |
2000年 | 292篇 |
1999年 | 315篇 |
1998年 | 134篇 |
1997年 | 131篇 |
1996年 | 145篇 |
1995年 | 130篇 |
1994年 | 169篇 |
1993年 | 100篇 |
1992年 | 231篇 |
1991年 | 286篇 |
1990年 | 260篇 |
1989年 | 227篇 |
1988年 | 221篇 |
1987年 | 216篇 |
1986年 | 194篇 |
1985年 | 158篇 |
1984年 | 92篇 |
1983年 | 61篇 |
1982年 | 40篇 |
1981年 | 33篇 |
1980年 | 30篇 |
1979年 | 28篇 |
1975年 | 29篇 |
1973年 | 33篇 |
1969年 | 28篇 |
1967年 | 27篇 |
1966年 | 33篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Sudden coronary death in Glasgow: the severity and distribution of chronic coronary atherosclerotic stenoses.
下载免费PDF全文
![点击此处可从《Heart (British Cardiac Society)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
A detailed analysis of the extent of coronary artery atherosclerosis was made in 92 white subjects (66 men and 26 women) who died suddenly from ischaemic heart disease. Stenoses resulting in loss of greater than or equal to 75% of luminal cross sectional area (significant stenosis) were found in 90 subjects and these were more extensive in the proximal coronary tree than in the distal. Thirty nine per cent had triple vessel disease, 37% had double vessel disease, and 23% had single vessel disease. In addition one man had an isolated significant stenosis affecting the left main coronary artery. The frequency of significant stenoses in the left main coronary artery was greater in men than in women. The arteries that were least affected were the distal branches of the right coronary artery. A notable feature was the widespread nature of the coronary atherosclerosis: only 26 of the total of 1840 segments of coronary artery examined in the 92 victims could be described as having a normal intima (less than or equal to 10% loss of the area within the internal elastic lamina). 相似文献
22.
I Ilardi S C Shiddo H H Mohamed C Mussa A S Hussein C S Mohamed K Bile A Sebastiani C Bianchini S Sanguigni 《Transactions of the Royal Society of Tropical Medicine and Hygiene》1987,81(2):336-338
About 85% of the population of two Somali communities harboured soil-transmitted intestinal nematodes and/or protozoa. The commonest parasite (75% in the Lafoole institution and 59% in the Afgoye institution) was Trichuris trichiura. Mixed infections were common. The source of infection is contaminated fields around dwelling quarters, because of indiscriminate defaecation. One of the factors responsible for the higher incidence of hookworm in Lafoole (45%) compared with Afgoye (1.5%) may be the different soil character of the surrounding fields. 相似文献
23.
T E Porter B M Hargis J L Silsby M E el Halawani 《General and comparative endocrinology》1989,74(3):400-405
This study was conducted to determine if lower steroid secretion by the small white follicles in incubating turkey hens contributes to lower circulating steroid concentrations during this time. Turkey hens were grouped as either laying or incubating. Serum samples and the ovarian small white follicles (SWF; 2-7 mm diameter) were collected from each hen. The SWF were pooled for each group and their cells were dispersed by trypsin digestion. Serum-luteinizing hormone (LH), progesterone (P), testosterone (T), and estradiol (E) concentrations were lower and serum prolactin concentration was higher during incubation than during egg laying. SWF cells from incubating hens secreted more P and T and less E in response to ovine luteinizing hormone (oLH) than did similar cell suspensions from laying hens. The incubating hens' SWF cells' capacity to secrete E but not their capacity to secrete P or T in vitro is consistent with the observed circulating levels. It is hypothesized that lower levels of circulating LH and/or higher levels of prolactin found in incubating hens may have a depressing effect on aromatase activity and/or an up-regulating effect on LH-induced P and T secretion by the SWF cells. 相似文献
24.
25.
Perianal mucinous adenocarcinoma is a rare tumour which may be associated with long‐standing chronic perianal sepsis. Early diagnosis is challenging and is based on a high index of clinical suspicion and specific histological features. Definitive treatment is surgical, in the form of an abdomino‐perineal resection. We hereby describe a case of a perianal mucinous adenocarcinoma arising from long‐standing recurrent perianal fistula and complement this with a brief review of the literature pertaining in particular to the management of this condition. 相似文献
26.
27.
28.
29.
30.
S Rashwan S Fahmy E A el Kader M Morta 《The Journal of the Egyptian Public Health Association》1991,66(1-2):173-191
A group of pregnant mothers above 35 years old were collected from the MCH centre in Kafr-El Zayat during a period of 10 months (82). A control group of mothers aged 20-30 years old were also selected during the same period (62). Those with specific diseases from both groups were excluded. During the repeated visits of those mothers to the MCH centre they were subjected to complete history taking, physical examination plus urine analysis & haemoglobin levelling. A special visit was performed by the researcher to the mothers on 7th day after labour to report on the outcome of labour. The present study revealed significant differences between mothers over 35 years and those of 20-30 years in the course of pregnancy, labour and their outcomes where the former group showed greater tendency to be at a higher risk. 相似文献