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   119958篇
  免费   11628篇
  国内免费   3530篇
耳鼻咽喉   362篇
儿科学   1623篇
妇产科学   858篇
基础医学   5462篇
口腔科学   2872篇
临床医学   13726篇
内科学   13057篇
皮肤病学   1898篇
神经病学   4902篇
特种医学   1399篇
外国民族医学   16篇
外科学   7062篇
综合类   17810篇
现状与发展   11篇
一般理论   30篇
预防医学   9158篇
眼科学   1464篇
药学   36551篇
  619篇
中国医学   8914篇
肿瘤学   7322篇
  2024年   1533篇
  2023年   2633篇
  2022年   3802篇
  2021年   5720篇
  2020年   6263篇
  2019年   5244篇
  2018年   4893篇
  2017年   5438篇
  2016年   5125篇
  2015年   4719篇
  2014年   8026篇
  2013年   11247篇
  2012年   7555篇
  2011年   7756篇
  2010年   6157篇
  2009年   5466篇
  2008年   5210篇
  2007年   5297篇
  2006年   4682篇
  2005年   4039篇
  2004年   3480篇
  2003年   3128篇
  2002年   2414篇
  2001年   2151篇
  2000年   1685篇
  1999年   1371篇
  1998年   1221篇
  1997年   1147篇
  1996年   928篇
  1995年   815篇
  1994年   746篇
  1993年   591篇
  1992年   664篇
  1991年   549篇
  1990年   452篇
  1989年   407篇
  1988年   388篇
  1987年   374篇
  1986年   264篇
  1985年   293篇
  1984年   243篇
  1983年   169篇
  1982年   158篇
  1981年   124篇
  1980年   89篇
  1979年   85篇
  1978年   80篇
  1977年   60篇
  1976年   65篇
  1975年   65篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Objective: A multidisciplinary vocational rehabilitation programme, the Vocational Enablement Protocol (VEP) was developed to address the specific needs of employees with hearing difficulties. In the current study we evaluated the process of implementing the VEP in audiologic care among employees with hearing impairment. Design: In conjunction with a randomized controlled trial, we collected and analysed data on seven process parameters: recruitment, reach, fidelity, dose delivered, dose received and implemented, satisfaction, and perceived benefit. Study sample: Sixty-six employees with hearing impairment participated in the VEP. The multidisciplinary team providing the VEP comprised six professionals. Results: The professionals performed the VEP according to the protocol. Of the recommendations delivered by the professionals, 31% were perceived as implemented by the employees. Compliance rate was highest for hearing-aid uptake (51%). Both employees and professionals were highly satisfied with the VEP. Participants rated good perceived benefit from it. Conclusions: Our results indicate that the VEP could be a useful treatment for employees with hearing difficulties from a process evaluation perspective. Implementation research in the audiological setting should be encouraged in order to further provide insight into parameters facilitating or hindering successful implementation of an intervention and to improve its quality and efficacy.  相似文献   
2.
The Present and Future of Clinical Psychology in Private Practice   总被引:1,自引:0,他引:1  
This article discusses clinical psychologists' current concerns, challenges, and opportunities in private practice. The future of clinicians in independent practice is presented within two paradigms, namely, psychology as a health profession, and psychology as life enhancement. Finally, the author argues that psychotechnology, corporate clinical psychology, and psychology as life enrichment will evolve within the future of clinical psychological independent practice.  相似文献   
3.
BACKGROUND: Computer-assisted image analysis has been proposed for human hair growth studies. METHODS: The performances of Trichoscan, a commercially available automated system combining epiluminiscence microscopy with digital image analysis, developed for office-based hair growth measurements, have been evaluated comparatively on the same skin sites using standardized photographic equipment and calibrated processing for contrast-enhanced phototrichogram (CE-PTG) analysis. This reference method has been validated with scalp biopsies and histological examination of serial sectioning. RESULTS: Besides edge effects, hair fibres escaped the Trichoscan analysis for various reasons including, but not limited to, thickness, pigmentation, closeness and crossing. CONCLUSION: Most of these problems have been identified in the late 1980s and remain largely unsolved by the processing software that was evaluated in 2004. Therefore claims promoting the Trichoscan method for accurate hair measurements in clinical trials on scalp and body hair are not supported by the present investigation. The speed at which the analysis is performed is outweighed by the errors in signal detection. Therefore we suggest that improvements must be clearly documented before Trichoscan is established for quantified diagnostic purposes and detailed hair cycle monitoring during hair trials.  相似文献   
4.
BACKGROUND: The recurrent chronic orofacial swelling caused by orofacial granulomatosis (OFG) can cause significant cosmetic and functional problems but can be prevented if the disease is diagnosed early and promptly treated. Although the enlargement of the lips is described to be the most common presenting complaint, the clinical onset of OFG may be characterized by minor associated mucosal and neurological manifestations, making early diagnosis very difficult or, sometimes, merely presumable. PATIENTS AND METHODS: We retrospectively analyzed the clinical manifestations of 19 patients with OFG, who were examined at our institution between 1998 and 2002, in order to determine their initial manifestations and presenting symptoms. RESULTS: A total of 10 patients showed classical recurrent enlargement of the lips (six lower; four upper) as presenting symptom. In the other nine patients, OFG onset was characterized by transient unilateral facial nerve palsy (two cases), intraoral manifestations (two cases), recurrent swelling of the periorbital area (two cases), of the chin (one case), of the zygomatic area (one case), and of the cheeks (one case). CONCLUSION: Our data underlined that OFG onset could be frequently characterized by widely variable, multiform, and temporary clinical findings. Involvement of atypical sites of the orofacial region and presence of single minor manifestations may occur as presenting symptoms, often preceding the development of traditional clinical findings.  相似文献   
5.
Four clinical trials of porcine islet transplantation have been reported, and there are verbal reports that clinical trials on much larger scales are continuing in centers in China and Russia. The four reported trials are briefly reviewed and, in the light of the present status of experimental islet xenotransplantation, consideration is given to whether such trials are currently justified. The Ethics Committee of the International Xenotransplantation Association has (1) emphasized the need for encouraging studies in non-human primates before clinical trials should be undertaken, (2) mandatory monitoring for the transfer of porcine microorganisms, and (3) careful regulation and oversight by recognized bodies. Other aspects of the topic, such as the need for informed consent, are briefly discussed. We conclude that, at the present time, more data documenting convincing efficacy, focused on clinically applicable immunosuppressive regimens, are needed to justify the initiation of closely monitored clinical trials. A clinical trial may then be justified even though the potential risk to the patients, and possibly for society, will not be zero.  相似文献   
6.
改变督导方式促进临床教学质量   总被引:1,自引:0,他引:1  
目的:发挥教学督导的作用,提高医学院校临床教学的质量.方法:对教学督导工作进行了大胆的改革:①督导前移,加强了教学的环节质量;②疏通反馈通道,保证教学督导效果;③言传身教,加强对青年教师的培养和指导;④扩大督导范围,促进各层次教学质量;⑤全程随机评价,客观评价教学效果.结果:保证了教学效果,使教学质量有了明显的提高.结论:加速我军现代化建设,培养高素质医学人才,教学督导的作用显的尤其重要.  相似文献   
7.
Background and Aim:  We recently reported that cyclooxygenase (COX)-2 is upregulated in the rat small intestine after administration of indomethacin, and this may be the key to non-steroidal anti-inflammatory drug (NSAID)-induced intestinal damage. The present study investigated the mechanism for COX-2 expression induced in the rat small intestine by indomethacin, in relation with ulcerogenic processes.
Methods:  Animals were given indomethacin or SC-560 p.o., and the intestinal mucosa was examined 24 h later.
Results:  Indomethacin caused hemorrhagic lesions in the small intestine, accompanied with an increase in intestinal motility, bacterial invasion and inducible nitric oxide synthase (iNOS) activity, as well as the expression of COX-2 mRNA in the mucosa. Although SC-560 did not cause any damage, this agent caused intestinal hypermotility, the bacterial invasion and the upregulation of COX-2 expression. The mucosal PGE2 content was decreased by SC-560 at 3 h but recovered 12 h later, and this recovery of PGE2 was attenuated by both atropine and ampicillin, in addition to rofecoxib. The intestinal hypermotility response to indomethacin was prevented by both 16,16-dimethyl PGE2 and atropine, but not ampicillin. Yet all these agents inhibited not only the bacterial invasion but also the expression of COX-2 and iNOS activity in the intestinal mucosa following indomethacin treatment, resulting in the prevention of intestinal lesions.
Conclusion:  These results suggest that COX-2 expression in the intestinal mucosa following the administration of indomethacin is associated with intestinal hypermotility and bacterial invasion. The intestinal hypermotility caused by COX-1 inhibition may be a key to COX-2 expression after administration of NSAIDs and their intestinal ulcerogenic properties.  相似文献   
8.
Intrastriatal transplantation of striatal neuroblasts from human fetuses is a promising approach for treatment of Huntington's disease, on the basis of many experimental animal studies and, most recently, pilot clinical trials. Technically, several issues remain to be resolved (e.g., the precise site of dissection of the fetal tissue; the number and location of the fetal striatal implants; or the use of immunosuppressive therapy), and await larger-scale trials and purposely designed protocols. Further clinical data must also be obtained, and preliminary promising results must be replicated in a patient group large enough to provide conclusive results. It is important to establish (1) the amount of clinical benefit provided to the patient by the grafted cells; (2) the anticipated duration of clinical benefits; and (3) the secondary rate of decline after the benefit of the graft has been overbalanced. Evaluation of these parameters will require very long-term follow-up of the patients involved, over several years after grafting, before the technique can eventually be proposed widely to patients.  相似文献   
9.
Summary. In this study, we have examined our records for the isolation of Candida tropicalis from clinical specimens of patients with heterogeneous clinical presentations during the past 5 years. We have found that this species ranks third among all yeasts in frequency of isolation from clinical specimens and that the trend of recovery from the specimens is rising over the years. The isolation rate of C. tropicalis was highest from urine specimens (36%) followed by respiratory specimens (22%). The frequency of isolation of C. tropicalis from vaginal specimens was relatively high (14%), however the trend was declining over the years. In general, the high recovery of Candida tropicalis from clinical specimens of patients with variable disease supports the views of this organism being a major pathogen.
Zusammenfassung. Die Studie basiert auf einer Durchsicht der Patientenarchive der letzten fünf Jahre auf die Isolationshäufigkeit von Candida tropicalis aus klinischen Untersuchungsmaterialien von Patienten mit unterschiedlichen klinischen Krankheitsbildern. Diese Hefeart war die dritthäufigste mit steigender Tendenz über die Jahre. Die Isolierungsrate von C. tropicalis war am höchsten aus Urin (36%), gefolgt von Respirationstrakt-Materialien (22%). Die Isolationshäufigkeit aus dem hinteren Scheidengewölbe war relativ hoch (14%), nahm jedoch mit den jahren ab. Allgemein unterstreicht die hohe Isolationsrate von C. tropicalis aus klinischen Untersuchungsmaterialien die ätiologische Bedeutung dieses Erregers.  相似文献   
10.
Abstract The aim of the present clinical trial was to test tolerability during 2 treatments with EMDOGAIN® in a large number of patients. An open, controlled study design in 10 Swedish specialist clinics was chosen, with a test group of 107 patients treated with EMDOGAIN® in connection with periodontal surgery at 2 surgical test sites per patient. The procedures were performed 2 to 6 weeks apart on one-rooted teeth with at least 4 mm deep intraosseous lesions. A control group of 33 patients underwent flap surgery without EMDOGAIN® at I comparable site. In total 214 test and 33 control surgeries were performed. Serum samples were obtained from test patients for analysis of total and specific antibody levels. 10 of the patients had samples taken before and after the first surgery. 56 other samples were taken after one treatment with EMDOGAIN®, and 63 after 2 treatments. None of the samples, not even from allergy-prone patients after 2 treatments, indicated deviations from established baseline ranges. This indicates that the immunogenic potential of EMDOGAIN® is extremely low when applied in conjunction with periodontal surgery. Comparison between the test and control groups demonstrated the same type and frequency of post-surgical experiences, i.e., reactions caused by the surgical procedure itself. Clinical probing and radiographic evaluation was performed at baseline and 8 months postsurgery. About half of the patients (44 test and 21 control) were also evaluated after 3 years. There was a significant difference between the test and control results at 8 months post surgery. and this difference had increased further at the 3 year follow-up. The 2.5–3 mm increase in attachment and bone level after treatment with EMDOGAIN® was of the same magnitude as seen in the studies with split-mouth design aiming for lest of effectiveness of EMDOGAIN®.  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