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   8865篇
  免费   608篇
  国内免费   207篇
耳鼻咽喉   1085篇
儿科学   196篇
妇产科学   66篇
基础医学   701篇
口腔科学   177篇
临床医学   969篇
内科学   536篇
皮肤病学   63篇
神经病学   312篇
特种医学   267篇
外国民族医学   1篇
外科学   1136篇
综合类   1536篇
现状与发展   1篇
预防医学   515篇
眼科学   251篇
药学   605篇
  17篇
中国医学   979篇
肿瘤学   267篇
  2024年   33篇
  2023年   131篇
  2022年   262篇
  2021年   401篇
  2020年   357篇
  2019年   300篇
  2018年   248篇
  2017年   297篇
  2016年   329篇
  2015年   303篇
  2014年   677篇
  2013年   649篇
  2012年   670篇
  2011年   604篇
  2010年   478篇
  2009年   433篇
  2008年   392篇
  2007年   374篇
  2006年   366篇
  2005年   320篇
  2004年   276篇
  2003年   227篇
  2002年   172篇
  2001年   180篇
  2000年   118篇
  1999年   135篇
  1998年   81篇
  1997年   95篇
  1996年   82篇
  1995年   71篇
  1994年   60篇
  1993年   59篇
  1992年   57篇
  1991年   36篇
  1990年   49篇
  1989年   28篇
  1988年   35篇
  1987年   25篇
  1986年   26篇
  1985年   58篇
  1984年   32篇
  1983年   32篇
  1982年   28篇
  1981年   14篇
  1980年   25篇
  1979年   16篇
  1978年   19篇
  1977年   4篇
  1976年   9篇
  1972年   2篇
排序方式: 共有9680条查询结果,搜索用时 15 毫秒
31.
Serum IgA and IgG functional antibodies and their subclasses to Streptococcus pneumoniae capsular antigen found in two aged‐matched cohorts of children with and without otitis media with effusion The relationship between acute otitis media and otitis media with effusion (OME) is uncertain and the aetiology of OME is multifactorial. Otitis media with effusion may be an inflammatory condition; both bacteria and viral infections could play a part in this inflammation. The four bacteria Streptococcus pneumoniae, Haemophilus influenza, Staphylococcus aureus and Branhamella catarrhalis cause 60% of the infections whereas S. pneumoniae accounts for up to 35%. IgA provides the dominant surface response to polysaccharide and lipopolysaccharide antigens, of which IgA2 is the main subclass. Once the mucosa has been breached, most protection is provided by IgG. IgG2 acts mainly against bacterial capsular antigens. This study looked at two groups of 50 children with and without OME who were aged between 3 and 10 years. The aims were to determine if, firstly, the levels of the serum immunoglobulins were different in the two groups, secondly whether these children made the appropriate antibody response to the capsular antigen to S. pneumoniae (PCP), and finally if there was a delay in the maturity of the IgA response. The total IgG, IgA and all subclass levels were measured using radial immunodiffusion. Levels of functional IgA and IgG were measured using ELISAs (25 patients in each group). The results were analysed with non‐parametric tests. The immunoglobulin levels were within the normal levels for both groups. There were very good correlations between the IgG total anti‐PCP and the IgG2 anti‐PCP (R > 0.9, p = 0.001). There was a good correlation between the levels of both IgG total and IgG2 anti‐PCP against IgA total anti‐PCP in both groups (R > 0.85, p > 0.01). This confirms a normal antibody response between both groups of patients. The ages of the controls and patients (50 samples) were correlated with increasing titres of circulating functional antibodies (P = 0.001). This is highly suggestive of a normal age‐related response. In conclusion, the findings were contradictory to our original hypothesis that there is a subtle difference in surface protection between children with and without OME. We believe that a previous history of recurrent acute otitis media is unrelated to the development of OME after 3 years of age.  相似文献   
32.
目的:观察美宝湿润烧伤膏在血栓性外痔和陈旧性肛裂切除术后治疗中的疗效。方法:术毕用MEBO纱布条填塞伤口,术后24小时取出纱布条,以后用MEBO涂于伤口内,每日2次,直至痊愈。结果:48例患者无术后伤口疼痛、出血、感染及肛门狭窄。伤口愈合时间短,治愈率高。结论:美宝湿润烧伤膏是血栓性外痔、陈旧性肛裂切除术后良好的局部治疗药物。  相似文献   
33.
34.
We report a case of Fusarium solani keratitis which highlights the difficulties often associated with management of fungal corneal infections. This case demonstrates several unusual and interesting features: the occurrence of deep fungal pathology after superficial injury, the difficulties encountered in attempting to isolate and identify the causative organism, and the protracted course taken by an organism often noted to be rapidly destructive. These features necessitated an individual approach to therapy, employing unconventional medical and surgical techniques to achieve a satisfactory outcome  相似文献   
35.
M. M. Moneer 《Surgery today》1997,27(11):1022-1025
This study consists of a preliminary report of 94 cases with various types of inguinal hernias. All cases were repaired by a new technique, in which the herniotomy is performed via a preperitoneal approach and the repair is achieved by using a bipedicled flap from the external oblique aponeurosis, which is transpositioned into the preperitoneal space and sutured to the iliopubic tract. The details of this technique are herein described. After a follow-up ranging from 15 to 48 months, both the early and late complications are presented. They were minimal and of minor significance, apart from a hernial recurrence in one case.  相似文献   
36.
37.
1999~2001年全国治疗药物监测室间质评结果   总被引:1,自引:0,他引:1  
郭健  陆红  谢洁红 《中国医药导刊》2002,4(3):229-230,228
目的:通过开展室间质量评价活动提高临床实验室的检验结果质量。方法:每年向参加治疗药物监测(TDM)室间质量评价活动的单位发放质控品10个批号,测定项目包括茶碱、地高辛、苯妥英、苯巴比妥、卡马西平和环孢菌素A,实验室用常规方法测定并回报测定结果,经计算机软件对全部结果进行统计分析。结果:2001年参加TDM室间质评的实验室数为48家,测定结果的平均及格率分别为茶碱94.2%、地高辛82.6%、苯妥英83.8%、苯巴比妥88.4%、卡马西平94.2和环孢菌素A92.4%。1999~2001年全国TDM室间质评的年平均及格率分别为78.7%、84.7%和89.3%。不同测定方法的精密度分别为茶碱4.4%~14.2%、地高辛11.5%~21.9%、苯妥英8.5%~29.5%、苯巴比妥8.2%~13.9%、卡马西平10.8%~12.6%和环孢菌素A15.5%~16.6%。结论:多数参加TDM室间质评实验室的测定结果有较好的一致性,及格率逐年上升,但参加TDM室间质评的实验室数占开展TDM的实验室总数的比例较低,在不同的测定方法间还存在较大的差异。  相似文献   
38.
本文解剖观察、测量了16具32例新生儿尸体的颈外静脉,结果其平均长度为4.37±0.94Cm,平均管径起点为0.16±0.05Cm,汇合点为0.24±0.07Cm,注入点为0.28±0.08Cm,被测量的颈外静脉中有98%的下段后壁上有一较大的属支.全长可分为三段,根据回流部位不同可分为三型,即锁骨下静脉型、静脉角型和颈内静脉型.  相似文献   
39.
Fungal infections still represent a serious complication after organ transplantation. Early diagnosis and aggressive treatment are crucial. Because of the many diagnostic problems involved, we present a case of mucormycosis--primarily affecting the paranasal sinuses with later intracranial extension--in a highly immunized recipient of a third renal transplant. Although fungal infection was suspected from various imaging techniques, only the detection of typical fungal hyphae in the infected tissue was diagnostic. Neither the blood tests and cerebrospinal fluid examinations performed nor cultures from maxillary sinus fluid were of any diagnostic help. Surgical debridement from a transnasal as well as an intracranial approach and systemic amphotericin B together with the discontinuation of immunosuppression after removal of the rejected graft were able to save the patient. This case stresses the importance of early diagnosis that can only be made from tissue biopsies and allows appropriate timely treatment.  相似文献   
40.
The cytotoxicity of extracts from rice cultures of five Fusarium avenaceum strains against the porcine epithelial kidney cell-line PK-15 was investigated using the Alamar Blue™ assay. After the identification of known fungal metabolites, cytotoxic extracts were fractionated using semi-preparative reversed-phase HPLC and normal phase LC, and the fractions were tested for cytotoxicity. In this way, two different groups of metabolites were identified as the major cytotoxic principles of the extracts. High concentrations of enniatins, especially enniatins B and B1, inhibited the metabolic activity of PK-15 cells. Furthermore, an unidentified metabolite, produced in high amounts by a strain that produced relatively small amounts of enniatins, was also found to be cytotoxic to PK-15 cells. This study shows that enniatins, a group of cyclic depsipeptides, which have been ignored as significant contributors to the toxicity of fungal extracts, may account for most of the observed effect for F. avenaceum.  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