全文获取类型
收费全文 | 3632篇 |
免费 | 198篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 39篇 |
儿科学 | 64篇 |
妇产科学 | 48篇 |
基础医学 | 502篇 |
口腔科学 | 43篇 |
临床医学 | 445篇 |
内科学 | 804篇 |
皮肤病学 | 32篇 |
神经病学 | 356篇 |
特种医学 | 90篇 |
外科学 | 426篇 |
综合类 | 20篇 |
一般理论 | 1篇 |
预防医学 | 335篇 |
眼科学 | 95篇 |
药学 | 276篇 |
中国医学 | 1篇 |
肿瘤学 | 261篇 |
出版年
2023年 | 23篇 |
2022年 | 47篇 |
2021年 | 79篇 |
2020年 | 46篇 |
2019年 | 46篇 |
2018年 | 52篇 |
2017年 | 45篇 |
2016年 | 76篇 |
2015年 | 97篇 |
2014年 | 115篇 |
2013年 | 148篇 |
2012年 | 227篇 |
2011年 | 267篇 |
2010年 | 132篇 |
2009年 | 176篇 |
2008年 | 260篇 |
2007年 | 294篇 |
2006年 | 311篇 |
2005年 | 304篇 |
2004年 | 224篇 |
2003年 | 213篇 |
2002年 | 180篇 |
2001年 | 26篇 |
2000年 | 20篇 |
1999年 | 23篇 |
1998年 | 44篇 |
1997年 | 33篇 |
1996年 | 39篇 |
1995年 | 22篇 |
1994年 | 24篇 |
1993年 | 38篇 |
1992年 | 13篇 |
1991年 | 11篇 |
1990年 | 12篇 |
1989年 | 12篇 |
1988年 | 15篇 |
1987年 | 8篇 |
1986年 | 12篇 |
1984年 | 5篇 |
1983年 | 11篇 |
1982年 | 9篇 |
1981年 | 5篇 |
1980年 | 11篇 |
1979年 | 5篇 |
1973年 | 4篇 |
1943年 | 3篇 |
1940年 | 3篇 |
1935年 | 4篇 |
1932年 | 8篇 |
1931年 | 3篇 |
排序方式: 共有3838条查询结果,搜索用时 0 毫秒
41.
42.
Schoofs MW van der Klift M Hofman A de Laet CE Herings RM Stijnen T Pols HA Stricker BH 《Annals of internal medicine》2003,139(6):476-482
Since most hip fractures are related to osteoporosis, treating accelerated bone loss can be an important strategy to prevent hip fractures. Thiazides have been associated with reduced age-related bone loss by decreasing urinary calcium excretion. 相似文献
43.
44.
45.
Hyo Jong Lee Adrian Preda Judith M. Ford Daniel H. Mathalon David B. Keator Theo G.M. van Erp Jessica A. Turner Steven G. Potkin 《Journal of Korean medical science》2015,30(5):625-631
Previous fMRI studies of sensorimotor activation in schizophrenia have found in some cases hypoactivity, no difference, or hyperactivity when comparing patients with controls; similar disagreement exists in studies of motor laterality. In this multi-site fMRI study of a sensorimotor task in individuals with chronic schizophrenia and matched healthy controls, subjects responded with a right-handed finger press to an irregularly flashing visual checker board. The analysis includes eighty-five subjects with schizophrenia diagnosed according to the DSM-IV criteria and eighty-six healthy volunteer subjects. Voxel-wise statistical parametric maps were generated for each subject and analyzed for group differences; the percent Blood Oxygenation Level Dependent (BOLD) signal changes were also calculated over predefined anatomical regions of the primary sensory, motor, and visual cortex. Both healthy controls and subjects with schizophrenia showed strongly lateralized activation in the precentral gyrus, inferior frontal gyrus, and inferior parietal lobule, and strong activations in the visual cortex. There were no significant differences between subjects with schizophrenia and controls in this multi-site fMRI study. Furthermore, there was no significant difference in laterality found between healthy controls and schizophrenic subjects. This study can serve as a baseline measurement of schizophrenic dysfunction in other cognitive processes.
Graphical Abstract
相似文献46.
Irene Paganini Vivian Y Chang Gabriele L Capone Jeremie Vitte Matteo Benelli Lorenzo Barbetti Roberta Sestini Eva Trevisson Theo JM Hulsebos Marco Giovannini Stanley F Nelson Laura Papi 《European journal of human genetics : EJHG》2015,23(7):963-968
Schwannomatosis is characterized by the development of multiple non-vestibular, non-intradermal schwannomas. Constitutional inactivating variants in two genes, SMARCB1 and, very recently, LZTR1, have been reported. We performed exome sequencing of 13 schwannomatosis patients from 11 families without SMARCB1 deleterious variants. We identified four individuals with heterozygous loss-of-function variants in LZTR1. Sequencing of the germline of 60 additional patients identified 18 additional heterozygous variants in LZTR1. We identified LZTR1 variants in 43% and 30% of familial (three of the seven families) and sporadic patients, respectively. In addition, we tested LZTR1 protein immunostaining in 22 tumors from nine unrelated patients with and without LZTR1 deleterious variants. Tumors from individuals with LZTR1 variants lost the protein expression in at least a subset of tumor cells, consistent with a tumor suppressor mechanism. In conclusion, our study demonstrates that molecular analysis of LZTR1 may contribute to the molecular characterization of schwannomatosis patients, in addition to NF2 mutational analysis and the detection of chromosome 22 losses in tumor tissue. It will be especially useful in differentiating schwannomatosis from mosaic Neurofibromatosis type 2 (NF2). However, the role of LZTR1 in the pathogenesis of schwannomatosis needs further elucidation. 相似文献
47.
Soza A Heller T Ghany M Lutchman G Jake Liang T Germain J Hsu HH Park Y Hoofnagle JH 《Journal of hepatology》2005,43(1):67-71
BACKGROUND/AIMS: Currently, there are no effective therapies available for patients with chronic hepatitis C who have failed to respond to optimal interferon alfa-based regimens. The aims of this pilot study were to assess the antiviral activity and safety of interferon gamma in chronic hepatitis C. METHODS: Patients with chronic hepatitis C, genotype 1, who had not responded to or who had relapsed after therapy with interferon alfa and ribavirin were enrolled in a trial of interferon gamma 1b given in doses of 100, 200 or 400 microg subcutaneously three times weekly for 4 weeks. Frequent blood samples were obtained for HCV RNA levels. RESULTS: Fourteen patients were enrolled. Geometric mean HCV RNA levels remained unchanged. Serum aminotransferase levels also did not change, while there were significant decreases in neutrophil counts (-41% from baseline) and hematocrit (-5%). Low grade fever and malaise were common with the first injection of interferon gamma, but no serious side effects were encountered. CONCLUSIONS: Although relatively well tolerated, interferon gamma in doses of 100-400 microg thrice weekly had no effect on HCV RNA levels in patients with chronic hepatitis C who had failed to achieve a sustained response to interferon alfa-based therapies. 相似文献
48.
49.
Shi Hong Kai Chook Shaun Leow Lowell Lim Shir Lynn Ramanathan Kollengode Kofidis Theo Kang Giap Swee 《Journal of thrombosis and thrombolysis》2021,52(2):680-682
Journal of Thrombosis and Thrombolysis - We present a novel case of a patient with nephrotic syndrome and previous left pneumonectomy who had a massive pulmonary embolism of his remnant right... 相似文献
50.
T Rispens J Meesters TH den Bleker P Ooijevaar-De Heer J Schuurman PW Parren A Labrijn RC Aalberse 《Molecular immunology》2013,53(1-2):35-42
Human IgG4 antibodies are remarkable not only because they can dynamically exchange half-molecules (Fab-arm exchange) but also for their ability to interact with the Fc part of IgG4 and other IgG subclasses. This rheumatoid factor-like binding of IgG4 does not appear to take place spontaneously, because it is only observed to solid-phase or antigen-bound IgG. We hypothesized that Fc-Fc interactions might involve (partial) dissociation of heavy chains. We investigated the molecular basis of these Fc-Fc interactions, and found that the structural features important for the exchange reaction also control the Fc binding activity. In particular, if arginine-409 in the CH(3)-CH(3) interface in IgG4 is mutated to lysine (the equivalent in IgG1), Fc-Fc interactions are formed 3 orders of magnitude less efficiently compared to the wild-type. This mutation was previously found to increase the CH(3)-CH(3) interaction strength in IgG4. Furthermore, of the two hinge isomers of IgG4, the intra-chain (non-covalently linked) form was found to form Fc-Fc interactions, but not the inter-chain form. Together, these results demonstrate that Fc-Fc interactions of IgG4 involve (partial or complete) dissociation of heavy chains. The promiscuity to other IgG subclasses suggests that IgG4 might act as scavenger to IgG molecules with impaired structural integrity. 相似文献