全文获取类型
收费全文 | 22080篇 |
免费 | 448篇 |
国内免费 | 59篇 |
专业分类
耳鼻咽喉 | 680篇 |
儿科学 | 227篇 |
妇产科学 | 1414篇 |
基础医学 | 2717篇 |
口腔科学 | 562篇 |
临床医学 | 2251篇 |
内科学 | 3668篇 |
皮肤病学 | 365篇 |
神经病学 | 1243篇 |
特种医学 | 612篇 |
外科学 | 3925篇 |
综合类 | 68篇 |
预防医学 | 1425篇 |
眼科学 | 598篇 |
药学 | 1681篇 |
中国医学 | 13篇 |
肿瘤学 | 1138篇 |
出版年
2022年 | 262篇 |
2021年 | 444篇 |
2020年 | 121篇 |
2019年 | 125篇 |
2018年 | 197篇 |
2017年 | 165篇 |
2016年 | 177篇 |
2015年 | 247篇 |
2014年 | 375篇 |
2013年 | 452篇 |
2012年 | 819篇 |
2011年 | 1201篇 |
2010年 | 666篇 |
2009年 | 290篇 |
2008年 | 861篇 |
2007年 | 1119篇 |
2006年 | 1187篇 |
2005年 | 1133篇 |
2004年 | 1308篇 |
2003年 | 1336篇 |
2002年 | 1307篇 |
2001年 | 929篇 |
2000年 | 1134篇 |
1999年 | 738篇 |
1998年 | 249篇 |
1992年 | 184篇 |
1991年 | 187篇 |
1990年 | 170篇 |
1989年 | 227篇 |
1988年 | 223篇 |
1987年 | 204篇 |
1986年 | 261篇 |
1985年 | 251篇 |
1984年 | 210篇 |
1983年 | 161篇 |
1979年 | 275篇 |
1978年 | 182篇 |
1977年 | 140篇 |
1976年 | 154篇 |
1975年 | 208篇 |
1974年 | 295篇 |
1973年 | 268篇 |
1972年 | 239篇 |
1971年 | 242篇 |
1970年 | 215篇 |
1969年 | 199篇 |
1968年 | 179篇 |
1967年 | 143篇 |
1966年 | 151篇 |
1965年 | 98篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
H Gregorek A Jung B Grabowska K Madaliński 《Archivum immunologiae et therapiae experimentalis》1991,39(5-6):519-527
Circulating immune complexes (CIC) containing HBsAg and HBeAg were identified in sera of 5 out of 6 children with hepatitis B mediated membranous glomerulonephritis. CIC were precipitated from sera by 3.5% PEG, washed and subsequently analysed after acid dissociation and trypsin digestion. HBsAg, anti-HBs and albumin; HBeAg, anti-HBe and anti-HBc were recovered from the isolated complexes and these findings are discussed. Analysis of 3.5% PEG mediated precipitate of human serum proteins showed the relatively high content of IgG classical pathway complement components: C1q, C4 and C3. 相似文献
82.
J Roliński Z M Rupniewska J Kowalewski M Kowal M Wach 《Acta haematologica Polonica》1990,21(2):185-191
In a group of 9 patients with chronic lymphocytic or lymphoplasmocytic leukaemia in clinical stage from 2 to 4 (classification of Rai et al.) 8 various CHOP programmes (cyclophosphamide, hydroxyldaunomycin, oncovin, prednisone) were used. In 6 cases (67%) partial remission was obtained, with normalization of peripheral blood and bone marrow patterns, with statistically significant decrease of the proportion of cells forming rosettes with murine erythrocytes, and with reduction or full normalization of the size of previously enlarged lymph nodes. In one case the control examination of a lymph node failed to demonstrate the previously present clone of cells with chromosomal aberration, although in histological examination the diagnosis of lymphoplasmocytic lymphoma was maintained. In the remaining 3 cases no partial remission was noted, and in one case progression was recognized. We think similarly as the French haematologists studying chronic lymphatic leukaemia, that the CHOP programme is effective in the treatment of chronic lymphatic or lymphoplasmocytic leukaemia. 相似文献
83.
Krzyzak AT Jasiński A Weglarz WP Adamek D Sagnowskil P Baj M 《Acta neurobiologiae experimentalis》2005,65(3):255-264
Magnetic Resonance Diffusion Tensor Imaging (DTI) of the control and traumatic injured spinal cord of a rat in vitro is reported. Experiments were performed on excised spinal cords from 10 Wistar rats, using a home-built 6.4 T MR microscope. MRI and histopathological results were compared. Presented results show that DTI of the spinal cord, perfused with formalin 10 minutes after the injury, can detect changes in water diffusion in white matter (WM) and in gray matter (GM), in areas extending well beyond the region of direct impact. Histology of neurons of the GM shows changes that can be attributed to ischemia. This is in agreement with the observed decrease of diffusion in the injured regions, which may be attributed to the cytotoxic edema due to ischemia. However, the diffusion changes in highly anisotropic WM seem to be caused by a direct action of mechanical force of impact, which significantly distorts the nerve fibers. 相似文献
84.
Vaccinia virus propagated in rotated cultures of RK13 cells was purified by sucrose density gradient zonal centrifugation. The purified virus was dissociated with sodium dodecyl sulfate end its protein composition analyzed by polyacrylamide gel electrophoresis. The protein composition of the virion envelope, isolated by the non-ionic detergent Nonidet P-40, was also determined. 相似文献
85.
E. Podsiadły J. Przyłuski A. Kwiatkowski M. Kruk M. Wszoła R. Nosek W. Rowiński W. Rużyłło S. Tylewska-Wierzbanowska 《European journal of clinical microbiology & infectious diseases》2005,24(8):507-513
Data published over the past decade show that Chlamydia pneumoniae is likely associated with the development of atherosclerosis. The aim of this study was to ascertain whether C. pneumoniae infections occur more frequently in patients with atherosclerosis than in healthy subjects. A total of 517 persons were studied. Serum samples, leukocytes, and tissue samples were assayed for the presence of C. pneumoniae-specific IgG and IgA antibodies and C. pneumoniae DNA. C. pneumoniae DNA was found in renal, iliac, and brachial vessels, but it was not detected in radial arteries. C. pneumoniae DNA was found most often in directional coronary atherectomy tissue specimens (11/41, 26.8%), but it was also found in the leukocytes of 14.9% (28/188) of patients with atherosclerosis and 24.6% (28/114) of patients without atheroma changes in vessels. Specific IgG and IgA antibodies were present in 63.8 and 49.9% of atheroma patients, respectively. The prevalence of C. pneumoniae antibodies differs significantly in patients with and without atherosclerosis (for IgG, p=0.002, and for IgA, p=0.006). The identification of persons with chlamydial infection of atherosclerotic arteries necessitates the examination of vascular tissues obtained during revascularization procedures. Serological investigation alone cannot identify individuals with vascular chlamydial infections. Detection of C. pneumoniae DNA in peripheral blood mononuclear cells does not seem to be the exclusive marker of persistent vascular infection. A more easily accessible parameter that allows prediction of chlamydial vascular infection is required. 相似文献
86.
The aim of this work was to demonstrate the role of interferon alpha (IA) in apoptosis control of cells of hypothalamohypophysial adrenocortical system (HHAS) in young and old mice under conditions of hyperoxia. The increase of functional activity of neurosecretory cells of hypothalamic paraventricular nucleus in old mice treated with IA was demonstrated, while no effect was found in young mice. This differences could be associated with aging changes in HHAS in intact old animals. Oxidative stress caused an increase in the number of cells synthesizing proapoptotic c-fos protein in paraventricular nucleus of mice of both age groups. However, the protective action of IA against the stress is expressed more actively and in more early stage of apoptosis in young mice. Thus, the degree of IA participation in the control of programmed cell death of hypothalamic cells depends on the age of the animal. In the adrenal zona fasciculata of young mice the number of apoptotic cells was significantly increased after IA administration while after hyperoxia or its combination with IA it remained at control level. In the adrenal gland of old mice the proportion of apoptotic cells was not different from that found in young mice and remained unchanged after all experimental challenges. 相似文献
87.
The review examines the current data on the cellular and tissue mechanisms of scar formation in the liver. On the basis of the analysis of the literature, authors conclude that to minimize the destructive processes in the liver, the most advisable and promising method during the operations on this organ is the use of laser surgical devices. However, the problems of the selection of the optimal regimes of laser radiation and of the methods of conducting these operations to promote reliable and rapid healing of postoperative wound of the liver. 相似文献
88.
Pig kidney diamine oxidase (DAO) and rat intestinal histaminase (Hi-are) activities are inhibited in vitro by high concentrations of both a substrate (histamine) and a coenzyme (pyridoxal-5-phosphate). This inhibition may be at least partially associated with the formation of a cyclic compound between histamine (Hi) and pyridoxal-5-phosphate (PLP).The dynamics of this cyclic compound formation in the presence of both enzymes has been examined. In an incubation mixture containing partially purified pig kidney DAO, the rate of cyclization decreased slightly as compared with a buffer. On the contrary, in the presence of crude rat intestinal histaminase, the rate of cyclization was inhibited significantly; this inhibition was proportional to the amount of enzyme preparation present in the incubation mixture. The possible mechanism of the influence of enzyme protein on the rate of cyclic compound formation, and its possible biological significance, are discussed. 相似文献
89.
J. Kusche T. Biegański R. Hesterberg C. -D. Stahlknecht K. -D. Feußner I. Stahlenberg W. Lorenz 《Inflammation research》1980,10(1-2):110-113
The distribution of diamine oxidase (DAO) activity was studied in patients having no carcinoma disease. Besides in gut DAO occurred in high activity only in kidney and mesenteric lymph nodes.In patients with adenocarcinoma of the large bowel or of the stomach the enzymic activity was reduced in the tumour tissue itself as compared with the adjacent mucosa in which part the highest activities were observed. In stomach it seemed most important that the enzymic activity was enhanced in the whole mucosa, also in a 10 cm distance from tumour where no histological alterations were found. This fact should be checked for significance in early tumour diagnosis.Supported by A. v. Humboldt Stiftung.Supported by a grant from Deutsche Forschungsgemeinschaft (Lo 199/7). 相似文献
90.