全文获取类型
收费全文 | 5421篇 |
免费 | 256篇 |
国内免费 | 32篇 |
专业分类
耳鼻咽喉 | 42篇 |
儿科学 | 97篇 |
妇产科学 | 61篇 |
基础医学 | 832篇 |
口腔科学 | 197篇 |
临床医学 | 330篇 |
内科学 | 1242篇 |
皮肤病学 | 59篇 |
神经病学 | 411篇 |
特种医学 | 231篇 |
外科学 | 1041篇 |
综合类 | 15篇 |
预防医学 | 186篇 |
眼科学 | 44篇 |
药学 | 373篇 |
中国医学 | 4篇 |
肿瘤学 | 544篇 |
出版年
2023年 | 33篇 |
2022年 | 47篇 |
2021年 | 98篇 |
2020年 | 44篇 |
2019年 | 68篇 |
2018年 | 92篇 |
2017年 | 79篇 |
2016年 | 97篇 |
2015年 | 100篇 |
2014年 | 125篇 |
2013年 | 141篇 |
2012年 | 193篇 |
2011年 | 223篇 |
2010年 | 130篇 |
2009年 | 138篇 |
2008年 | 217篇 |
2007年 | 232篇 |
2006年 | 238篇 |
2005年 | 223篇 |
2004年 | 247篇 |
2003年 | 238篇 |
2002年 | 215篇 |
2001年 | 211篇 |
2000年 | 195篇 |
1999年 | 191篇 |
1998年 | 61篇 |
1997年 | 57篇 |
1996年 | 50篇 |
1995年 | 47篇 |
1994年 | 44篇 |
1993年 | 52篇 |
1992年 | 143篇 |
1991年 | 112篇 |
1990年 | 127篇 |
1989年 | 122篇 |
1988年 | 111篇 |
1987年 | 93篇 |
1986年 | 105篇 |
1985年 | 96篇 |
1984年 | 69篇 |
1983年 | 60篇 |
1979年 | 51篇 |
1978年 | 35篇 |
1974年 | 34篇 |
1973年 | 42篇 |
1971年 | 34篇 |
1970年 | 33篇 |
1969年 | 32篇 |
1967年 | 36篇 |
1966年 | 34篇 |
排序方式: 共有5709条查询结果,搜索用时 15 毫秒
41.
An autopsy case of adult hepatoblastoma is presented. The patient was an 82-year-old male with chronic hepatitis of 7 years' duration. The liver tumor was detected 6 months before death. Autopsy revealed a large hepatic tumor occupying about 80% of the entire liver. Histologically, the tumor showed typical features of mixed epithelial- and mesenchymal-type hepatoblastoma. The epithelial component consisted of fetal and embryonal cell types. The mesenchymal component showed primitive spindle-shaped cells with various degrees of cellularity. Chondroid areas and a few foci of osteoid formation were also present. 相似文献
42.
The effect of bile duct ligation on enzyme activities in the subfractions of the rat liver plasma membrane was investigated. Two subfractions were isolated from the rat liver plasma membrane by homogenization and subsequent centrifugation in a discontinuous sucrose gradient. The light subfraction contained fragments of the bile canalicular surface and the heavy fraction contained fragments of the sinusoidal and lateral surfaces of the hepatocyte. Bile duct ligation decreased NaK ATPase and Mg-ATPase activity in the light subfraction, whereas it had no significant effect on these enzyme activities in the heavy fraction. Leucyl-β-naphthylamidase activity was reduced and alkaline phosphatase activity was increased in both subfractions. These facts suggested that ligation of the bile duct led to loss of the secretory polarity of the liver cell. The in vitro effects of some bile acids on the membranebound enzymes in the light subfraction were investigated, and a possible involvement of chenodeoxycholic acid in the alteration of enzyme activities in the bile canalicular membrane was suggested. 相似文献
43.
44.
45.
K Maruoka M Yamanaka M Misago K Nakata J Tsukada K Nagata T Sato N Mori S Oda S Chiba 《Rinsho byori. The Japanese journal of clinical pathology》1990,38(10):1161-1166
The activities of RNase (RNase-U and RNase-C) were determined in the serum and leukocytes of 277 patients with 14 cases of various kinds of eosinophilia (not less than 10(3)/microliters), 28 cases of chronic myelocytic leukemia (CML), using polyuridylic acid and polycytidylic acid as synthetic substrates according to the method of Raddi et al. Serum RNase-U activity, serum RNase-C activity and the activity ratio (U/C x 10(-3)) were 55 +/- 14 U, 1,280 +/- 235 U and 44 +/- 11 (mean +/- SD), 196 +/- 137, 1,992 +/- 1,134 U and 97 +/- 38, and 110 +/- 50 U, 1,854 +/- 625 U and 65 +/- 13 for normal subjects, eosinophilia and CML (untreated), respectively. U/C ratio in eosinophilia and CML (untreated) showed a highly significant positive correlation (p less than 0.001) with peripheral eosinophil count; the activity of serum RNase-U per cells in the supernatant of eosinophil homogenate rose significantly (p less than 0.001) compared with that of lymphocytes or granulocytes. Besides, serum and eosinophil RNase-U had a similar optimal pH. These results suggested that serum RNase-U in eosinophilia originated mostly from eosinophils and its rise was correlated strongly with the increase in eosinophils. 相似文献
46.
Summary Human cells doubly transformed by Rous sarcoma virus and SV40 (RSb cells) formed syncytia by cocultivation with Mason-Pfizer monkey virus (MPMV)-producing cells. This cell fusion was blocked by anti-MPMV serum indicating that the phenomenon is MPMV specific. The RSb cells were successfully used for MPMV infectivity assay in the same manner as KC cells.With 1 Figure 相似文献
47.
48.
49.
50.