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   1262318篇
  免费   96665篇
  国内免费   1572篇
耳鼻咽喉   16318篇
儿科学   41007篇
妇产科学   34957篇
基础医学   189480篇
口腔科学   34820篇
临床医学   117755篇
内科学   247686篇
皮肤病学   27291篇
神经病学   101977篇
特种医学   46778篇
外国民族医学   265篇
外科学   178672篇
综合类   25786篇
现状与发展   3篇
一般理论   569篇
预防医学   104619篇
眼科学   28032篇
药学   92610篇
  6篇
中国医学   2023篇
肿瘤学   69901篇
  2018年   13546篇
  2017年   10402篇
  2016年   11335篇
  2015年   13089篇
  2014年   18031篇
  2013年   27511篇
  2012年   37615篇
  2011年   40002篇
  2010年   23084篇
  2009年   22275篇
  2008年   37798篇
  2007年   40428篇
  2006年   40009篇
  2005年   39141篇
  2004年   37585篇
  2003年   35998篇
  2002年   34902篇
  2001年   56066篇
  2000年   57088篇
  1999年   48124篇
  1998年   13412篇
  1997年   12250篇
  1996年   12661篇
  1995年   11927篇
  1994年   11119篇
  1993年   10412篇
  1992年   38224篇
  1991年   37699篇
  1990年   36464篇
  1989年   35284篇
  1988年   32707篇
  1987年   32051篇
  1986年   30546篇
  1985年   28823篇
  1984年   21970篇
  1983年   19214篇
  1982年   11373篇
  1981年   10329篇
  1979年   20960篇
  1978年   15406篇
  1977年   12799篇
  1976年   11853篇
  1975年   12820篇
  1974年   15591篇
  1973年   15375篇
  1972年   14520篇
  1971年   13556篇
  1970年   12790篇
  1969年   12068篇
  1968年   11233篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
221.
222.
223.
Lucio phenomenon is an atypical reaction of leprosy, characterized by vasculitic lesions that can mimic antiphospholipid syndrome (APS) clinically. Distinguishing the two can be difficult as antiphospholipid autoantibodies may be present in patients with leprosy. We report on a 32‐year‐old female patient presenting with a sudden onset of fever, hemorrhagic bullae, and skin necrosis on her lower legs. She was treated for APS due to the presence of antiphospholipid antibodies but had an inadequate response. A skin biopsy revealed thrombotic vasculopathy and necrotizing vasculitis associated with aggregation of foam cells in the perivascular area and subcutis, with acid‐fast bacilli in the histiocytes and blood vessel walls. Direct immunofluorescence showed IgM, C3, and fibrinogen deposition in the superficial and deep dermal blood vessels. The pathology confirmed the diagnosis of Lucio phenomenon, and appropriate therapy was given. It is essential to evaluate the patient comprehensively, including clinical, serological, and pathological aspects, to obtain the correct diagnosis.  相似文献   
224.
225.
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   
226.
2‐deoxy D‐glucose (2DG) was tested for efficacy in treating alopecia areata using the C3H/HeJ skin graft model. 2DG has proven to be efficacious in treatment of various mouse models of autoimmunity with minimal serious side effects noted. This agent has been shown to normalize abnormally activated T‐cell populations while also preventing cell surface expression of NKG2D; key factors defining alopecia areata disease progression. Daily oral ingestion of 2DG via drinking water to mice with patchy or diffuse alopecia areata for 16 weeks failed to prevent expansion of alopecia or cause regrowth of hair in treated mice. Histologically, there were no differences between treated and control groups. These results indicate that, while 2DG is effective for some autoimmune diseases, it was not efficacious for the cell‐mediated autoimmune mouse disease, alopecia areata.  相似文献   
227.

Background Context

Long-term follow-up of patient-reported outcome measures (PROM) is essential in both modern spinal care and research. Lack of time and staff are commonly reported barriers to implementing long-term follow-up of PROM. Automated and digital follow-up systems for PROM collection are seeing widespread use, yet their validity and comparative effectiveness have never been evaluated.

Purpose

The present study aimed to assess the validity of digital follow-up systems in comparison with the conventional paper-based follow-up (PB-FU).

Study Design

This is a retrospective analysis of prospectively collected double follow-up data.

Patient Sample

Patients who underwent lumbar spinal fusion for spondylolisthesis or degenerative disc disease between 2013 and 2016 were included in the study.

Outcome Measures

The study determined the Oswestry Disability Index (ODI) and Numeric Rating Scale (NRS) for back and leg pain severity at baseline, 6 weeks, 12 months, and 24 months.

Materials and Methods

After lumbar spinal fusion surgery, a double follow-up of PROM was carried out by conventional PB-FU during clinical visits, while simultaneously completing an automatically dispatched digital follow-up questionnaire. As the primary end point, we assessed the intraindividual discrepancy in PROM between PB-FU and automated digital follow-up (AD-FU).

Results

Forty patients completed all parts of the dual follow-up trajectory and were analyzed. We detected no discrepancy in ODI or NRS for back and leg pain severity at any of the baseline, 6-week, 12-month, or 24 month follow-ups (all p>.05). This was confirmed in a sensitivity analysis.

Conclusions

In an analysis of dual paper-based and digital follow-up after lumbar fusion surgery, patients report highly similar values using either method of follow-up. It appears that AD-FU without incentives produces lower response rates. To reassess the validity of these systems for data collection in spinal patient care, a prospective validation with higher statistical power is warranted.  相似文献   
228.
229.
Congenital heart disease is a rare but important finding in adults who experience sudden death. Examination of the congenitally malformed heart has historically been considered esoteric and best left to those with expertise. The Cardiac Risk in the Young cardiovascular pathology laboratory based at St George's University of London has now received over 6,000 cases. Of these, 21 congenitally malformed hearts were retained for research and educational purposes. Hearts were assessed using sequential segmental analysis, and causes of death were adjudicated based on thorough macroscopic examination and histology. Congenital malformations that were encountered included atrial septal defects, ventricular septal defects, tetralogy of Fallot, and transposition of the great arteries in both its regular and congenitally corrected variants. Findings also included hearts with mirror-imaged and isomeric atrial appendages. Direct causes of death included myocardial fibrosis, pulmonary hypertension, and hemorrhage. A small but notable proportion did not reveal a substrate for arrhythmia, raising the question of whether the terminal event was due to the congenital heart disease itself, or an underlying channelopathy. Here, we demonstrate the value of simple sequential segmental analysis in describing and categorizing the cases, with the concept of the “morphological method” serving to identify the distinguishing features of the cardiac components. Clin. Anat. 33:394–404, 2020. © 2019 Wiley Periodicals, Inc.  相似文献   
230.
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