首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1352篇
  免费   157篇
  国内免费   4篇
耳鼻咽喉   9篇
儿科学   34篇
妇产科学   23篇
基础医学   351篇
口腔科学   6篇
临床医学   201篇
内科学   239篇
皮肤病学   247篇
神经病学   92篇
特种医学   13篇
外科学   97篇
综合类   3篇
预防医学   91篇
眼科学   13篇
药学   74篇
中国医学   2篇
肿瘤学   18篇
  2023年   7篇
  2022年   6篇
  2021年   12篇
  2020年   21篇
  2019年   27篇
  2018年   33篇
  2017年   30篇
  2016年   37篇
  2015年   45篇
  2014年   50篇
  2013年   63篇
  2012年   102篇
  2011年   97篇
  2010年   49篇
  2009年   58篇
  2008年   79篇
  2007年   67篇
  2006年   65篇
  2005年   52篇
  2004年   53篇
  2003年   52篇
  2002年   40篇
  2001年   60篇
  2000年   59篇
  1999年   48篇
  1998年   24篇
  1997年   17篇
  1996年   7篇
  1995年   9篇
  1994年   9篇
  1993年   13篇
  1992年   28篇
  1991年   18篇
  1990年   20篇
  1989年   28篇
  1988年   26篇
  1987年   10篇
  1986年   12篇
  1985年   8篇
  1984年   7篇
  1983年   5篇
  1981年   4篇
  1979年   3篇
  1977年   4篇
  1975年   5篇
  1972年   3篇
  1971年   3篇
  1967年   3篇
  1966年   3篇
  1939年   3篇
排序方式: 共有1513条查询结果,搜索用时 31 毫秒
71.
72.
Severe maternal psychopathology and infant-mother attachment   总被引:3,自引:0,他引:3  
Eighty-two mother-infant dyads, comprising women with psychiatric disorder and individually matched controls, were followed up over the children's 1st year of life. The mothers with mental illness consisted of two subgroups: first, 25 severely mentally ill mothers who had been admitted to a psychiatric unit with their infants; and second, 16 mothers from a community sample meeting research diagnostic criteria for unipolar, nonpsychotic depression. With the exception of six dyads in the in-patient group, observations were made of the mother-infant interaction and the quality of the infant-mother attachment relationship at 12 months. The nature and course of the mothers' illness was also documented. Although few residual symptoms of maternal mental illness were detected at 1 year postpartum, interactional disturbances were evident among the case group dyads. A strong association was revealed between infant-mother attachment quality and maternal diagnosis; a manic episode of illness in the postpartum period was related to security in the attachment relationship, and psychotic or nonpsychotic depression was related to insecurity. Concurrent patterns of mother-infant interaction provided support for this finding.  相似文献   
73.
Nucleic acid sequence-based amplification (NASBA) was used for detection of the human cytomegalovirus (CMV) immediate early-1 (IE) and the late pp67 mRNA in 353 blood samples collected from 34 liver transplant patients. The diagnostic value of these assays was compared to that of the pp65 antigenemia assay. Overall, 95 and 42% of the antigenemia-positive samples were IE NASBA and pp67 NASBA positive, respectively. Although the results from pp67 NASBA and the antigenemia assay appeared to correspond poorly, a clear correlation was seen between pp67 NASBA-negative results and low numbers of pp65 antigen-positive cells. Twenty patients (59%) were treated with ganciclovir after the diagnosis of symptomatic CMV infection. Before initiation of the antiviral therapy, the antigenemia assay detected the onset of symptomatic infection in all patients, whereas 95 and 60% of these patients were IE NASBA and pp67 NASBA positive, respectively. Although the sensitivity of IE NASBA was very high, the positive predictive value (PPV) of this assay for the onset of a symptomatic infection was only 63%. The PPV of the antigenemia assay as well as pp67 NASBA was considerably higher (80 and 86%, respectively). Thus, the detection of IE mRNA using NASBA appears to be particularly useful as a marker for early initiation of antiviral therapy in patients at high risk for the development of a symptomatic infection. Also, IE NASBA was found to be more sensitive than the antigenemia assay for monitoring CMV infection during antiviral therapy. On the contrary, pp67 NASBA did not appear to have additional diagnostic value compared to the antigenemia assay.  相似文献   
74.
75.
Peripheral T-cell lymphomas consist of a clinically heterogeneous group of malignant disorders whose immunophenotype usually corresponds to that of normal mature T cells. We describe and correlate the clinical, histopathologic, phenotypic, and genotypic findings in two patients with malignant lymphoma presenting with hepatosplenic disease. The morphologic pattern of lymphoma was that of a sinusal/sinusoidal infiltration in spleen, marrow, and liver. This morphologic characteristic was associated with the presence of a productive clonal rearrangement of the T-cell receptor (TCR) delta gene. Lymphoma cells expressed a CD3-TCR-gamma delta- phenotype. They were also double negative (ie, CD4-CD8-) and lacked the CD5 and CD7 antigens. In one patient, tumor progression was associated with phenotypic changes that resulted in a CD3-TCR-gamma delta- phenotype with the same delta-gene rearrangement as initially. These observations suggest the existence of a new type of peripheral T-cell lymphoma characterized by its hepatosplenic presentation, and by the sinusal/sinusoidal tropism and the TCR-gamma delta phenotype of the malignant cells.  相似文献   
76.
77.
DNA polymorphisms of Arcobacter butzleri outbreak-related strains and Arcobacter reference strains were determined by use of the polymerase chain reaction with primers aimed at repetitive sequences. The epidemiological relationship among 14 outbreak-related strains was substantiated, as they showed virtually no genomic variations. Their DNA amplification patterns were, however, clearly different from those of all Arcobacter reference strains studied; each reference strain was characterized by a unique DNA fingerprint.  相似文献   
78.
Background : We performed a retrospective analysis of the maze IV procedures performed in our surgical department for concomitant atrial fibrillation.

Methods : Preoperative, in-hospital and postoperative follow-up data were collected from 46 consecutive patients who underwent the maze IV operation between April 2006 and December 2010. All electrocardiograms and Holters were reviewed.

Results : One patient died in-hospital. During a mean follow-up of 25 ± 16.3 months seven patients died: two related to a hemorrhagic stroke, one due to right ventricular failure, the remainder deaths were not cardiac related. The success rate, defined as no recurrence of AF or atrial flutter with a blanking period of 6 months postoperatively, was 73.7%. Plots of probability of freedom of atrial fibrillation over time are drawn and reach a stable level after one year. Conclusions : The mid term results of the maze IV procedures for concomitant atrial fibrillation are very good. The results are stable for the remainder of follow-up.  相似文献   
79.
The current study investigated loss of control (LC) over eating and the role of anxiety, depression and emotional eating in a sample of both treatment seeking (N = 115) and non‐treatment seeking (N = 73) overweight youngsters (aged 8–18) using a semi‐structured clinical interview and self‐report questionnaires. It was found that treatment seekers reported twice as much LC (40%) compared to non‐treatment seekers (21%). Cross‐sectional prediction models indicated that increased anxiety was associated with emotional eating and LC. Emotional eating tended to mediate the relationship between anxiety and LC. Increased depression was associated with emotional eating but not with LC. Especially overweight treatment seekers turn out to be at risk for LC. Because LC may develop as a result of inadequate coping with negative emotions like anxiety, obesity treatment should focus on teaching more effective coping strategies. Longitudinal research is recommended to further elaborate affect regulation and LC. Copyright © 2008 John Wiley & Sons, Ltd and Eating Disorders Association.  相似文献   
80.
The gene encoding α-T-catenin, CTNNA3, is positioned within a region on chromosome 10, showing strong evidence of linkage to Alzheimer’s disease (AD), and is therefore a good positional candidate gene for this disorder. We have demonstrated that α-T-catenin is expressed in human brain, and like other α-catenins, it inhibits Wnt signaling and is therefore also a functional candidate. We initially genotyped two single-nucleotide polymorphisms (SNPs) in the gene, in four independent samples comprising over 1200 cases and controls but failed to detect an association with either SNP. Similarly, we found no evidence for association between CTNNA3 and AD in a sample of subjects showing linkage to chromosome 10, nor were these SNPs associated with Aβ deposition in brain. To comprehensively screen the gene, we genotyped 30 additional SNPs in a subset of the cases and controls (n>700). None of these SNPs was associated with disease. Although an excellent candidate, we conclude that CTNNA3 is unlikely to account for the AD susceptibility locus on chromosome 10.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号