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   1670篇
  免费   73篇
  国内免费   7篇
耳鼻咽喉   17篇
儿科学   53篇
妇产科学   24篇
基础医学   292篇
口腔科学   24篇
临床医学   123篇
内科学   360篇
皮肤病学   24篇
神经病学   150篇
特种医学   49篇
外科学   195篇
综合类   33篇
一般理论   1篇
预防医学   127篇
眼科学   10篇
药学   131篇
中国医学   13篇
肿瘤学   124篇
  2023年   8篇
  2022年   13篇
  2021年   16篇
  2020年   23篇
  2019年   20篇
  2018年   28篇
  2017年   22篇
  2016年   15篇
  2015年   28篇
  2014年   56篇
  2013年   65篇
  2012年   133篇
  2011年   72篇
  2010年   46篇
  2009年   51篇
  2008年   94篇
  2007年   67篇
  2006年   71篇
  2005年   64篇
  2004年   87篇
  2003年   97篇
  2002年   85篇
  2001年   58篇
  2000年   35篇
  1999年   41篇
  1998年   15篇
  1997年   15篇
  1996年   17篇
  1995年   15篇
  1994年   27篇
  1993年   39篇
  1992年   19篇
  1991年   25篇
  1990年   21篇
  1989年   16篇
  1988年   14篇
  1987年   14篇
  1985年   8篇
  1984年   13篇
  1983年   15篇
  1982年   22篇
  1981年   8篇
  1980年   14篇
  1979年   14篇
  1978年   13篇
  1977年   15篇
  1974年   12篇
  1973年   14篇
  1971年   7篇
  1966年   10篇
排序方式: 共有1750条查询结果,搜索用时 498 毫秒
1.
Annals of Nuclear Medicine - The Response Evaluation Criteria In Solid Tumors (RECIST) is the most used radiological method for evaluating response after peptide receptor radionuclide therapy...  相似文献   
2.
3.
儿童肺炎支原体感染状况分析   总被引:2,自引:0,他引:2  
目的 探讨儿童的肺炎支原体(MP)感染现状及早期诊断的意义。方法 检测181例就诊儿童血液标本分析MP感染的状况。结果 肺炎支原体感染率为29.8%;男性患儿MP检测阳性率(35.7%)明显高于女性患儿(16.4%)(P<0.01);5岁以下患儿阳性率超过50%,且有3例婴儿检测阳性;10-12月份支原体肺炎发病率明显增加,占全年的40.7%。结论 针对儿童支原体肺炎的发病情况,早诊断,早治疗,利于患儿尽早康复,防止肺部病变迁延及肺外并发症的发生。  相似文献   
4.

Background  

Communication training builds on the assumption that understanding of the concepts related to professional communication facilitates the training. We know little about whether students' knowledge of clinical communication skills is affected by their attendance of communication training courses, or to what degree other elements of the clinical training or curriculum design also play a role. The aim of this study was to determine which elements of the curriculum influence acquisition of knowledge regarding clinical communication skills by medical students.  相似文献   
5.

Background  

The behaviour of children with Attention-Deficit/Hyperactivity Disorder is characterized by low predictability of responding. Low behavioural predictability is one way of operationalizing intra-individual ADHD-related variability. ADHD-related variability may be caused by inefficient behavioural selection mechanisms linked to reinforcement and extinction, as suggested by the recently published dynamic developmental theory (DDT) of ADHD. DDT argues that ADHD is a basic neurobehavioural disorder, caused by dysfunctioning dopamine systems. For establishing ADHD as a neurobehavioural disorder, findings from studies conducted in Western countries should be replicated in other cultural populations. The present study replicated the study conducted in Norway, with children from the Limpopo province in the Republic of South Africa.  相似文献   
6.
流行性出血热人群传播速度的定量研究   总被引:1,自引:0,他引:1  
选取家鼠型EHF中发病区人群血清EHF抗体阳性率资料,试用可逆催化模型对EHF人群传播速度进行定量研究。结果表明:所建立的可逆催化模型其理论值与实际值理论拟合较好,用χ^2做配合适度检验,P〉0.05。证实可逆催化模型可用来作EHF人群中传播速度的定量研究。还发现在家鼠型EHF疫区每1000人中约有80人因有效接触而获得感染,同时又有40人血清EHF抗体转阴。  相似文献   
7.
Intravenous injections of 50 μ.g Staphylococcus aureus enterotoxin B (SEB) or bacterial lipopolysaccharide (LPS) are lethal, provided that mice are simultaneously sensitized with either N-galactosamine (GalN) or the anti-glucocorticoid RU-38486. Similar to the synthetic glucocorticoid (GC) receptor agonist dexamethasone, pharmacological doses of the immunomodulator linomide (quinoline-3-carboxamide) prevent death in all four models of lethal septic shock (LPS + GalN, LPS + RU-38486, SEB + GalN, and SEB + RU-38486) and inhibit the secretion of tumor necrosis factor, one of the major intermediate effector molecules of SEB and LPS toxicity. In this system, cyclosporine A (CsA), although effective in suppressing SEB toxicity, fails to counteract the lethal effect of LPS. This observation, together with the fact that linomide acts in the presence of excess amounts of GC receptor antagonist, indicates that linomide functions in a different way to that of known immunosuppressive agents like CsA and GC.  相似文献   
8.
Lipopolysaccharide (LPS) and related bacterial products can be recognized by host inflammatory cells in a particulate, bacterium-bound form, as well as in various soluble, released forms. In the present study we have compared the mechanisms used by LPS, detoxified LPS (DLPS), and mannuronic acid polymers (M-polymers), in solution or covalently linked to particles, in stimulating monocytes to tumor necrosis factor (TNF) production. The addition of recombinant LPS binding protein (LBP) and/or soluble CD14 (sCD14) enhanced the production of TNF from monocytes stimulated with soluble LPS, DLPS, or M-polymer, but did not affect the response to M-polymer or DLPS attached to particles. Treatment of monocytes with antibody to CD14, CD18, or CD11b showed that CD14, but not CR3 (CD11b/CD18), mediated monocyte TNF production in response to the soluble antigens. In contrast, anti-CD14, anti-CD11b and anti-CD18 monoclonal antibodies all inhibited the response to the particulate stimuli. On the other hand, B975, a synthetic analog of Rhodobacter capsulatus lipid A, completely abrogated the monocyte TNF response induced by LPS but did not affect the TNF induction by DLPS or M-polymer, either in soluble or particulate forms. These data demonstrate that the engagement of immune receptors by bacterial products such as LPS, DLPS, and M-polymer is dependent upon the presentation form of their constituent carbohydrates, and that factors such as aggregation state, acylation, carbohydrate chain length, and solid versus liquid phase of bacterial ligands influence the mechanisms used by cells in mediating proinflammatory responses.  相似文献   
9.
Gonadal dysgenesis with 45,X/46,X,dic(Yp) mosaicism   总被引:1,自引:0,他引:1  
A female patient with a gonodal mucinous cystadenoma on the right side and a gonado-blastoma on the left was found to be a 45,X/46,X,dic (Yp) mosaic, This brings the total number of cases with dicentric Y chromosome reported to date to 23.
Together with the available evidence, the information derived from this case supports the hypothesis that the gene on the long arm of the Y chromosome is responsible for the initiation of testicular differentiation, whereas that on the short arm is responsible for the maturation of the testes.  相似文献   
10.
A cohort of 485 couples starting their first in-vitro fertilization(IVF) attempt between January, 1989 and February, 1991 inclusive,were followed until June 1, 1992. A total of 1086 treatmentcycles were initiated (mean 2.2, range 1–6). Of these,235 (21.8%) cycles were cancelled, giving a total of 851 embryoreplacements (mean 1.7, range 1–5). After IVF treatment,189 women have either delivered or have an ongoing pregnancyin the second or third trimester. This gives a baby take-homerate of 17.4% per started cycle and 22.2% per embryo replacement.For 91 (18.6%) of the couples, the treatment was abandoned priorto completion of the three scheduled IVF attempts and 57 (11.7%)of these had no completed IVF cycles. In the group of coupleswith reduced sperm quality, the delivery rate was significantlylower than that of the other groups. A total of 193 women hadembryos cryopreserved in at least one IVF cycle; 124 of thesewomen started a frozen embryo replacement cycle and 88 had atleast one cycle with replacement of frozen/thawed embryos, resultingin 25 deliveries/ongoing pregnancies. Due to the Norwegian lawon assisted procreation 65 (33.7%) of the women have had theirfrozen embryos thawed and discarded after 12 months of storage.The cryopreservation programme, with the limitations of theNorwegian law, gives a 5.2% increase in the baby take-home ratefor women entering the IVF programme, an increase of 13.2% inthe number of ongoing pregnancies/deliveries and an 11.6% increasein number of children/viable fetuses. A total of 214 women havedelivered or have ongoing pregnancies in the second or thirdtrimester. This represents 44.1% of the 485 women accepted forIVF treatment, irrespective of whether they were treated ornot, and 50.0% of those couples who completed at least one IVFcycle.  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