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   4868篇
  免费   330篇
  国内免费   23篇
耳鼻咽喉   31篇
儿科学   150篇
妇产科学   113篇
基础医学   763篇
口腔科学   134篇
临床医学   373篇
内科学   1166篇
皮肤病学   219篇
神经病学   552篇
特种医学   48篇
外科学   337篇
综合类   22篇
预防医学   415篇
眼科学   146篇
药学   382篇
中国医学   39篇
肿瘤学   331篇
  2024年   3篇
  2023年   39篇
  2022年   89篇
  2021年   178篇
  2020年   103篇
  2019年   168篇
  2018年   186篇
  2017年   134篇
  2016年   154篇
  2015年   162篇
  2014年   222篇
  2013年   262篇
  2012年   453篇
  2011年   431篇
  2010年   250篇
  2009年   195篇
  2008年   354篇
  2007年   298篇
  2006年   280篇
  2005年   291篇
  2004年   260篇
  2003年   226篇
  2002年   232篇
  2001年   19篇
  2000年   17篇
  1999年   33篇
  1998年   30篇
  1997年   25篇
  1996年   21篇
  1995年   13篇
  1994年   8篇
  1993年   12篇
  1992年   10篇
  1991年   7篇
  1990年   4篇
  1989年   2篇
  1988年   2篇
  1987年   7篇
  1986年   9篇
  1983年   2篇
  1982年   5篇
  1981年   4篇
  1980年   2篇
  1978年   3篇
  1974年   2篇
  1973年   2篇
  1970年   1篇
  1968年   1篇
  1967年   1篇
  1965年   2篇
排序方式: 共有5221条查询结果,搜索用时 15 毫秒
81.
82.
Prefrontal serotonin 2A receptors (5‐HT2ARs) have been linked to the pathogenesis and treatment of schizophrenia. Many antipsychotics fully occupy 5‐HT2AR at clinical relevant doses, and activation of 5‐HT2A receptors by lysergic acid diethylamide (LSD) and LSD‐like drugs induces a schizophrenia‐like psychosis in humans. Subchronic phencyclidine (PCP) administration is a well‐established model for schizophrenia‐like symptoms in rodents. The aim of the present study was to investigate whether subchronic PCP administration changes expression, binding, or functionality of cortical 5‐HT2ARs. As a measure of 5‐HT2AR functionality, we used the 5‐HT2AR agonist 2,5‐dimethoxy‐4‐iodoamphetamine (DOI)‐induced head‐twitch response (HTR) and mRNA expression of the immediate‐early genes (IEGs) activity‐related cytoskeletal associated‐protein (Arc), c‐fos, and early growth response protein 2 (egr‐2) in the frontal cortex. Mice were treated with PCP (10 mg/kg) or saline for 10 days, followed by a 5‐day washout period. The PCP pretreatment increased the overall induction of HTR and frontal cortex IEG mRNA expression following a single challenge with DOI. These functional changes were not associated with changes in 5‐HT2AR binding. Also, binding of the 5‐HT1AR and the 5‐HT transporter was unaffected. Finally, basal mRNA level of Arc was increased in the prefrontal cortex after subchronic PCP administration as revealed with in situ hybridization. Together these findings indicate that PCP administration produces changes in the brain that result in an increase in the absolute effect of DOI. Therefore, neurotransmission involving the 5‐HT2AR could contribute to the behavioral deficits observed after PCP treatment. © 2013 Wiley Periodicals, Inc.  相似文献   
83.
Abstract

This study compared symptomatological and personality differences between individuals with threshold bulimia nervosa (BN; n=39) and those with subthreshold BN (n=39) and their short-term response to a brief outpatient intervention. Participants were matched using a pairwise matching procedure, taking into account age, age of onset, and duration of the disorder. Both groups received the same brief outpatient psychoeducational therapy. The same assessment measures were used before and after treatment. With the exception of some clinical and psychopathological symptoms (higher depression and phobic anxiety in threshold BN), there were no significant between-group differences on scales of general psychopathology or personality traits. At the end of treatment, there were no significant between-group differences on abstinence rates for binge eating and vomiting, number of sessions attended, or dropout rates. Threshold BN and subthreshold BN share common psychopathological symptoms and personality traits. No differences in therapy outcome were observed for the two groups after a brief group psychoeducational intervention.  相似文献   
84.
Abstract

Objectives: Little empirical literature focuses on psychotherapists' cultivation of internal states of mind necessary for controlling attention and responding empathically to the client. We explore the effects of mindfulness training on emotional and attentional measures in Spanish resident intern psychiatrists and clinical psychologists. Method: One hundred and three residents were assigned to an experimental group (n = 60) that completed an 8-week mindfulness training versus a wait-list control group (n = 43). We evaluated emotional variables (sadness, anxiety, and anger, using standard instruments), state of mindfulness (using the Mindfulness Awareness Attention Scale), and attentional control variables using objective measures such as a continuous performance task and the Stroop task before and after mindfulness training. Results: Our study provides data that suggest that mindfulness training significantly improves measures of trait anger and attentional control. Conclusions: Further research is needed to replicate these findings, explore the effects of mindfulness training on other aspects of emotional regulation and cognition, and evaluate the impact of these effects within clinical situations.  相似文献   
85.
86.
Characterization of multiprotein complexes (MPCs) is an important step toward an integrative view of protein interaction networks and prerequisite for a molecular understanding of how a certain MPC functions. Here, we present a technique utilizing monoclonal subunit-specific antibodies for an electrophoretic immunoshift assay in Blue Native-gels (NAMOS-assay), which allows the determination of the stoichiometry of MPCs. First, we use the B cell antigen receptor as a model MPC whose stoichiometry is known, confirming the HC(2)LC(2)Igalpha/beta(1) stoichiometry. Second, we demonstrate that the digitonin-extracted T cell antigen receptor (TCR) extracted from T cells has a stoichiometry of alphabetaepsilon(2)gammadeltazeta(2). We then show that the NAMOS-assay does not require purified MPCs, since it can determine the stoichiometry of an MPC in cell lysates. The NAMOS-assay is also compatible with use of epitope tags appended to the protein of interest, as e.g. the widely used HA-tag, and anti-epitope antibodies for the assay. Given its general applicability, this method has a wide potential for MPC research.  相似文献   
87.
Topical DNA vaccination (DermaVir) facilitates antigen presentation to naive T cells. DermaVir immunization in mice, using HIV-1 Env and Gag, elicited cellular immune responses. Boosting with HIV-1 gp120 Env and p41 Gag augmented Th1 cytokine levels. Intramuscular DNA administration was less efficient in priming antigen-specific cytokine production and memory T cells. In rhesus macaques, DermaVir immunization induced Gag- and Env-specific Th1 and Th2 cytokines and generation of memory T cells. Boosting of DermaVir-primed serum antibody levels was noted following gp140(SHIV89.6P)/p27(SIV) immunization. Rectal challenge with pathogenic R5-tropic SHIV162P3 resulted in control of plasma viremia (4/5 animals) that was reflected in jejunum, colon and mesenteric lymph nodes. An inverse correlation was found between Gag- and Env-specific central memory T cell responses on the day of challenge and plasma viremia at set point. Overall, the topical DermaVir/protein vaccination yields central memory T cell responses and facilitates control of pathogenic SHIV infection.  相似文献   
88.
Selective luteinizing hormone deficiency due to mutations in the luteinizing hormone beta-subunit gene (LHB) is a rare cause of hypogonadism. We describe the clinical features of a consanguineous family in which three siblings, two men and one woman, had hypogonadism related to isolated luteinizing hormone deficiency. These subjects have a newly discovered homozygous mutation of a 5' splice site in LHB: IVS2+1G-->C. This mutation disrupts the splicing of messenger RNA (mRNA), generating a gross abnormality in the processing of the luteinizing hormone beta-subunit mRNA, which abrogates the secretion of luteinizing hormone. We also determined that the female phenotype of this LHB mutation is characterized by normal pubertal development, secondary amenorrhea, and infertility.  相似文献   
89.

Background

Patients with Diabetic Foot Ulcer (DFU) show high levels of depression and anxiety symptoms. The loss of a limb is undoubtedly a devastating experience and several studies have shown that anxiety and depression symptoms are a common reaction after a lower limb amputation (LLA). However, no study has focused on the immediate emotional reactions to LLA as a personal factor based on the ICF Model.

Objective

This study focused on the characterization of anxiety and depression levels, before and after surgery, differences in levels of depression and anxiety before and after surgery and the predictors of anxiety and depression one month after surgery, in a sample of patients with DFU.

Methods

This was a longitudinal study with 179 patients with Diabetes Mellitus Type 2 and DFU indicated for amputation, screened for the presence of anxiety and depression symptoms during the hospitalization that preceded amputation and one month after surgery, during a follow-up consultation.

Results

The results showed a significant effect of anxiety and depression symptoms at pre-surgery in the prediction of anxiety and depression symptoms one month after LLA. Patients showed higher levels of anxiety than depression symptoms at pre-surgery, although anxiety significantly decreased on month after surgery. Both anxiety and depression symptoms contributed to depression after LLA, although anxiety at pre-surgery was the only predictor of anxiety at post-surgery.

Conclusions

Tailored multidisciplinary interventions need to be developed providing support before and after an amputation surgery, in order to reduce anxiety and depression symptoms and promote psychological adjustment to limb loss.  相似文献   
90.
Metastatic lesions of primary tumors, which originate in different parts of the body, comprise almost 1 % of different types of oral cancers. These lesions can affect either bones or soft tissues in the maxillofacial region. Whenever the maxillofacial area is affected, the most common location is in the molar region of the mandible. The clinical presentation of mandibular metastasis follows a clinical pattern characterized by irradiated dental pain in the third molar region. The most frequent sign is parethesia of the area innervated by the mandibular alveolar dental nerve. Differential diagnosis and treatment of these patients can be extremely difficult because there a number of pathologic conditions with similar symptoms and because diagnostic examination can be highly confusing. The aim of this article is to present a case of prostatic adenocarcinoma where the only metastasis was found in the jaw. A literature review will be presented, hoping to contribute to the scarce information regarding this lesion, due to its low frequency and atypical expression of this type of metastasis in terms of etiology, biological behavior and treatment.  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