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   4773篇
  免费   305篇
  国内免费   2篇
耳鼻咽喉   113篇
儿科学   75篇
妇产科学   70篇
基础医学   615篇
口腔科学   60篇
临床医学   479篇
内科学   1085篇
皮肤病学   181篇
神经病学   514篇
特种医学   163篇
外科学   505篇
综合类   22篇
一般理论   1篇
预防医学   361篇
眼科学   76篇
药学   339篇
中国医学   3篇
肿瘤学   418篇
  2023年   33篇
  2022年   53篇
  2021年   141篇
  2020年   102篇
  2019年   146篇
  2018年   137篇
  2017年   103篇
  2016年   116篇
  2015年   120篇
  2014年   189篇
  2013年   243篇
  2012年   347篇
  2011年   344篇
  2010年   192篇
  2009年   151篇
  2008年   269篇
  2007年   270篇
  2006年   270篇
  2005年   253篇
  2004年   220篇
  2003年   175篇
  2002年   159篇
  2001年   78篇
  2000年   74篇
  1999年   68篇
  1998年   33篇
  1997年   33篇
  1996年   36篇
  1995年   48篇
  1994年   24篇
  1993年   27篇
  1992年   49篇
  1991年   52篇
  1990年   40篇
  1989年   43篇
  1988年   46篇
  1987年   33篇
  1986年   22篇
  1985年   27篇
  1984年   33篇
  1983年   28篇
  1982年   34篇
  1981年   20篇
  1979年   24篇
  1978年   15篇
  1977年   16篇
  1975年   15篇
  1974年   20篇
  1972年   18篇
  1970年   12篇
排序方式: 共有5080条查询结果,搜索用时 15 毫秒
151.
152.
153.
Testicular germ cell tumours, seminoma (SE) and non-seminoma (NS), of young adult men develop from a precursor cell, carcinoma in situ (CIS), which resembles foetal gonocytes and retains embryonic pluripotency. We used microarrays to analyse microRNA (miRNA) expression in 12 human testis samples with CIS cells and compared it with miRNA expression profiles of normal adult testis, testis with Sertoli-cell-only that lacks germ cells, testis tumours (SE and embryonal carcinoma (EC), an undifferentiated component of NS) and foetal male and female gonads. Principal components analysis revealed distinct miRNA expression profiles characteristic for each of the different tissue types. We identified several miRNAs that were unique to testis with CIS cells, foetal gonads and testis tumours. These included miRNAs from the hsa-miR-371-373 and -302-367 clusters that have previously been reported in germ cell tumours and three miRNAs (hsa-miR-96, -141 and -200c) that were also expressed in human epididymis. We found several miRNAs that were upregulated in testis tumours: hsa-miR-9, -105 and -182-183-96 clusters were highly expressed in SE, while the hsa-miR-515-526 cluster was high in EC. We conclude that the miRNA expression profile changes during testis development and that the miRNA profile of adult testis with CIS cells shares characteristic similarities with the expression in foetal gonocytes.  相似文献   
154.
Cold atmospheric plasmas (CAPs) are promising medical tools and are currently applied in dermatology and epithelial cancers. While understanding of the biomedical effects is already substantial, knowledge on the contribution of individual ROS and RNS and the mode of activation of biochemical pathways is insufficient. Especially the formation and transport of short-lived reactive species in liquids remain elusive, a situation shared with other approaches involving redox processes such as photodynamic therapy. Here, the contribution of plasma-generated reactive oxygen species (ROS) in plasma liquid chemistry was determined by labeling these via admixing heavy oxygen 18O2 to the feed gas or by using heavy water H218O as a solvent for the bait molecule. The inclusion of heavy or light oxygen atoms by the labeled ROS into the different cysteine products was determined by mass spectrometry. While products like cysteine sulfonic acid incorporated nearly exclusively gas phase-derived oxygen species (atomic oxygen and/or singlet oxygen), a significant contribution of liquid phase-derived species (OH radicals) was observed for cysteine-S-sulfonate. The role, origin, and reaction mechanisms of short-lived species, namely hydroxyl radicals, singlet oxygen, and atomic oxygen, are discussed. Interactions of these species both with the target cysteine molecule as well as the interphase and the liquid bulk are taken into consideration to shed light onto several reaction pathways resulting in observed isotopic oxygen incorporation. These studies give valuable insight into underlying plasma–liquid interaction processes and are a first step to understand these interaction processes between the gas and liquid phase on a molecular level.

Cold atmospheric plasmas (CAPs) are promising medical tools producing short-lived reactive species.  相似文献   
155.
We present a case of a previously healthy and active 64‐year‐old man who experienced a rapid neuropsychiatric decline. All tests for metabolic causes, neuroinfection, intracranial infarction or tumor were negative. By the means of magnetic resonance imaging, electroencephalography and the anti‐Hu antibody test the patient was diagnosed with paraneoplastic limbic encephalitis related to prostate cancer. The patient died within 6 months. We review the literature on prostate cancer‐related paraneoplastic limbic encephalitis. High‐risk prostate cancer can trigger paraneoplastic limbic encephalitis, a rapidly progressive neurological syndrome with a bad prognosis.  相似文献   
156.
157.
Objectives. Angiography by selective catheterization is the reference standard for coronary bypass graft patency assessment but carries a risk of serious complications. We have investigated whether 16-slice multidetector spiral computed tomography (MDCT) can substitute for selective angiography. Design. Two to three years after coronary artery bypass grafting, 45 patients with a total of 156 bypasses (100 single and 28 sequential grafts) were examined with both MDCT and conventional selective angiography on the same day. The bypasses were classified as patent, stenotic or occluded. Results. The likelihood ratio for MDCT-detected occlusion was 40, reflecting a fairly high combined sensitivity and specificity. However, 24% of the distal anastomoses could not be evaluated by MDCT, mainly because of respiratory movements, artifacts due to metal clips, and small vessel dimensions. Moreover, seven out of 117 bypasses (6%) deemed evaluable by MDCT were wrongly classified by this method. Conclusions. At present, 16-slice MDCT cannot replace selective angiography for assessment of coronary bypass graft patency since 24% of bypasses could not be evaluated by this method, and an error rate of 6% is unacceptable.  相似文献   
158.
159.
The objective of this study was to describe the temperament dimension profiles assessed by the Temperament and Character Inventory (TCI) among young adults with the DSM-III-R personality disorder (PD). Our hypothesis was that PD clusters and separate PDs can be distinguished from one another by their specific temperament profiles. As a part of the 31-year follow-up survey of the prospective Northern Finland 1966 Birth Cohort, the cohort members living in the city of Oulu at the age of 31 years (n=1609) were invited to participate in a two-phase field study. The Structured Clinical Interview for DSM-III-R for PDs (SCID–II) was used as diagnostic instrument. The final study sample consisted of the 1311 subjects who had completed the Hopkins Symptom Check List-25 questionnaire for screening and had given a written informed consent. Of the 321 SCID interviewed subjects, 74 met the criteria for at least one PD and had completed the TCI. The mean TCI scores of subjects with PD and control subjects without PD (n=910) were compared. Low Novelty Seeking, high Harm Avoidance and low Reward Dependence characterized cluster A and C PDs. Subjects with a cluster B PD did not differ from controls, except for Novelty Seeking, which was high. The temperament dimensions could not distinguish different PDs very well, with the only exception of persons with obsessive–compulsive PD. PD clusters were associated with different profiles of temperament, lending some support for Cloninger's typology.  相似文献   
160.
Abstract

Purpose: Autism spectrum disorder (ASD) includes core symptoms that affect general and social development. High risk of developing comorbid disorders such as anxiety is prominent. Up to 60% of children with ASD suffer from anxiety disorders which can negatively influence educational, social and general development together with quality of life. This study is the first to investigate the feasibility of the manualised cognitive behavioural therapy (CBT) group programme 'Cool Kids ASD' for anxiety adapted for children with ASD in a general hospital setting.

Methods: Nine children, aged 9–13 years, with ASD and anxiety recruited from a public child psychiatric health clinic were enrolled in the study. Outcome measures were collected from both child and parent pre- and post-treatment and at 3-month follow-up and included scores from a semi-structured anxiety interview, together with questionnaires on anxiety symptoms, life interference, children's automatic thoughts and satisfaction with the programme.

Results: Eight out of nine families found the programme useful and would recommend it to other families in a similar situation. Six families attended all 12 sessions in the programme, two missed one session and one family only managed to attend eight sessions. At follow-up, five children were free of all anxiety diagnoses and a further two out of the nine children no longer met the criteria for their primary anxiety diagnosis.

Conclusions: This study suggests that the transition of the group programme 'Cool Kids ASD' from University Clinics to standard child psychiatric clinical settings is feasible. Further randomised studies are needed to confirm the efficacy of the programme in a larger sample.  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