全文获取类型
收费全文 | 20728篇 |
免费 | 1416篇 |
国内免费 | 59篇 |
专业分类
耳鼻咽喉 | 125篇 |
儿科学 | 449篇 |
妇产科学 | 281篇 |
基础医学 | 2781篇 |
口腔科学 | 341篇 |
临床医学 | 2575篇 |
内科学 | 3642篇 |
皮肤病学 | 205篇 |
神经病学 | 1844篇 |
特种医学 | 710篇 |
外科学 | 2853篇 |
综合类 | 258篇 |
一般理论 | 28篇 |
预防医学 | 2679篇 |
眼科学 | 432篇 |
药学 | 1621篇 |
中国医学 | 36篇 |
肿瘤学 | 1343篇 |
出版年
2024年 | 15篇 |
2023年 | 123篇 |
2022年 | 183篇 |
2021年 | 517篇 |
2020年 | 315篇 |
2019年 | 448篇 |
2018年 | 529篇 |
2017年 | 399篇 |
2016年 | 433篇 |
2015年 | 584篇 |
2014年 | 747篇 |
2013年 | 986篇 |
2012年 | 1663篇 |
2011年 | 1682篇 |
2010年 | 966篇 |
2009年 | 904篇 |
2008年 | 1472篇 |
2007年 | 1608篇 |
2006年 | 1460篇 |
2005年 | 1467篇 |
2004年 | 1435篇 |
2003年 | 1346篇 |
2002年 | 1160篇 |
2001年 | 156篇 |
2000年 | 114篇 |
1999年 | 163篇 |
1998年 | 222篇 |
1997年 | 154篇 |
1996年 | 136篇 |
1995年 | 102篇 |
1994年 | 114篇 |
1993年 | 87篇 |
1992年 | 52篇 |
1991年 | 50篇 |
1990年 | 37篇 |
1989年 | 38篇 |
1988年 | 30篇 |
1987年 | 37篇 |
1986年 | 32篇 |
1985年 | 32篇 |
1984年 | 27篇 |
1983年 | 32篇 |
1982年 | 30篇 |
1981年 | 25篇 |
1980年 | 21篇 |
1978年 | 10篇 |
1977年 | 8篇 |
1976年 | 17篇 |
1973年 | 4篇 |
1972年 | 5篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
111.
Cruzipain, the major cysteinyl proteinase of Trypanosoma cruzi, is expressed by all developmental forms and strains of the parasite and stimulates potent humoral and cellular immune responses during infection in both humans and mice. This information suggested that cruzipain could be used to develop an effective T. cruzi vaccine. To study whether cruzipain-specific T cells could inhibit T. cruzi intracellular replication, we generated cruzipain-reactive CD4(+) Th1 cell lines. These T cells produced large amounts of gamma interferon when cocultured with infected macrophages, resulting in NO production and decreased intracellular parasite replication. To study the protective effects in vivo of cruzipain-specific Th1 responses against systemic T. cruzi challenges, we immunized mice with recombinant cruzipain plus interleukin 12 (IL-12) and a neutralizing anti-IL-4 MAb. These immunized mice developed potent cruzipain-specific memory Th1 cell responses and were significantly protected against normally lethal systemic T. cruzi challenges. Although cruzipain-specific Th1 responses were associated with T. cruzi protective immunity in vitro and in vivo, adoptive transfer of cruzipain-specific Th1 cells alone did not protect BALB/c histocompatible mice, indicating that additional immune mechanisms are important for cruzipain-specific immunity. To study whether cruzipain could induce mucosal immune responses relevant for vaccine development, we prepared recombinant attenuated Salmonella enterica serovar Typhimurium vaccines expressing cruzipain. BALB/c mice immunized with salmonella expressing cruzipain were significantly protected against T. cruzi mucosal infection. Overall, these data indicate that cruzipain is an important T. cruzi vaccine candidate and that protective T. cruzi vaccines will need to induce more than CD4(+) Th1 cells alone. 相似文献
112.
An eighth locus for autosomal dominant retinitis pigmentosa is linked to chromosome 17q 总被引:5,自引:2,他引:5
Bardienb Soraya; Ebenezer Neil; Greenberg Jacquie; Inglehearn Chris F.; Bartmann Lecia; Goliath Rene; Beighton Peter; Ramesar Rajkumar; Bhattacharya Shomi S. 《Human molecular genetics》1995,4(8):1459-1462
Retinitis pigmentosa is one of the most common causes of severevisual handicap in middle to late life. Prior to this report,seven loci had previously been mapped for the autosomal dominantform of this disorder (adRP). We now report the identificationof a novel adRP locus on chromosome 17q. To map the new locus,we performed linkage analysis with microsatellite markers ina large South African kindred. After exclusion of 13 RP candidategene loci (including rhodopsin and peripherin-RDS), we obtainedsignificant positive lod scores at zero recombination fraction( 相似文献
113.
114.
Use of a heminested reverse transcriptase PCR assay for detection of astrovirus in environmental swabs from an outbreak of gastroenteritis in a pediatric primary immunodeficiency unit
下载免费PDF全文
![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Gallimore CI Taylor C Gennery AR Cant AJ Galloway A Lewis D Gray JJ 《Journal of clinical microbiology》2005,43(8):3890-3894
115.
Profiles of HIV voluntary counseling and testing of clients at a district hospital,Chiang Mai Province,northern Thailand,from 1995 to 1999 总被引:3,自引:0,他引:3
Kawichai S Celentano DD Chaifongsri R Nelson KE Srithanaviboonchai K Natpratan C Byerer C Khamboonruang C Tantipiwatanaskul P 《Journal of acquired immune deficiency syndromes (1999)》2002,30(5):493-502
Voluntary HIV counseling and testing (VCT) is a central component of comprehensive HIV prevention strategies targeting individual risk reduction. VCT data are essential for planning and improving HIV/AIDS intervention strategies. The objective of this study is to describe demographic profiles, reasons for seeking HIV counseling and testing, rate of declining HIV testing after pretest counseling, rate of failure to return for HIV test results, and HIV prevalence and associations among 3570 clients who sought VCT at Sansai Hospital in northern Thailand from 1995 to 1999. Data were abstracted retrospectively from client-level data recorded by the hospital counselors on a standard form. HIV prevalence was 29% and remained high throughout the study period. Reasons for seeking VCT for men and women were markedly different and highly correlated with rates of declining the test, failure to return for test results, and HIV prevalence. Declining VCT and failing to return were high among uneducated clients (p <.001). Failure to return among men was associated with HIV prevalence (OR = 1.72, p =.003), particularly for those who had risk behaviors (OR = 5.92, p <.001) and those who wanted to know their HIV serostatus (OR = 4.44, p =.002). Overall, VCT acceptance and returning for test results were high. VCT services at the community level can reach high-risk individuals, especially male partners of women tested as part of routine prenatal care. 相似文献
116.
Utility of a multiplex PCR assay for detecting herpesvirus DNA in clinical samples 总被引:4,自引:0,他引:4
下载免费PDF全文
![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Druce J Catton M Chibo D Minerds K Tyssen D Kostecki R Maskill B Leong-Shaw W Gerrard M Birch C 《Journal of clinical microbiology》2002,40(5):1728-1732
A multiplex PCR was designed to amplify herpes simplex virus types 1 and 2, cytomegalovirus, and varicella-zoster virus DNA present in a diverse range of clinical material. The susceptibility of these viruses to in vivo inhibition by at least one antiviral drug was an important consideration in their inclusion in the multiplex detection system. An aliquot of equine herpesvirus was introduced into each specimen prior to extraction and served as an indicator of potential inhibitors of the PCR and a detector of suboptimal PCR conditions. Compared to virus isolation and immunofluorescence-based antigen detection, the multiplex assay yielded higher detection rates for all viruses represented in the assay. The turnaround time for performance of the assay was markedly reduced compared to those for the other techniques used to identify these viruses. More than 21,000 tests have been performed using the assay. Overall, the multiplex PCR enabled the detection of substantially increased numbers of herpesviruses, in some cases in specimens or anatomical sites where previously they were rarely if ever identified using traditional detection methods. 相似文献
117.
118.
F. Facchetti Chris de Wolf-Peeters J. J. van den Oord C. J. L. M. Meijer S. T. Pals V. J. Desmet 《Immunology letters》1989,20(4):277-281
So-called plasmacytoid T cells represent a subset of monocyte related cells, which share with endothelium the CD36+CD11b− (OKM5+OKM1−) phenotype. The reactivity of plasmacytoid T cells with rat monoclonal antibody HECA-452, highly specific for high endothelial venules, was analyzed in reactive lymph nodes. In all cases, HECA-452 not only labelled the endothelium of high endothelial venules, but also strongly reacted with singular and clustered plasmacytoid T cells. The HECA-452 positivity for high endothelial venules and plasmacytoid T cells visualized a lymph node compartment extending from the subcapsular sinus to the corticomedullary junction. This compartment surrounded the composite nodule and was designated the ”extranodular“ compartment. The cooccurrence of plasmacytoid T cells and high endothelial venules in this extranodular compartment, together with their immunophenotypical similarities, may be indicative of functional co-operations. 相似文献
119.
Grossman M Koenig P DeVita C Glosser G Moore P Gee J Detre J Alsop D 《Neuropsychology》2003,17(4):658-674
Patients with probable Alzheimer's disease (AD) have difficulty understanding verbs. To investigate the neural basis for this deficit, the authors used functional magnetic resonance imaging to examine patterns of neural activation during verb processing in 11 AD patients compared with 16 healthy seniors. Subjects judged the pleasantness of verbs, including MOTION verbs and COGNITION verbs. Healthy seniors and AD patients both activated posterolateral temporal and inferior frontal regions during judgments of verbs. These activations were relatively reduced and somewhat changed in their anatomic distribution in AD patients compared with healthy seniors, particularly for the subcategory of MOTION verbs, but AD patients showed minimal activation in association with COGNITION verbs. These findings imply that poor performance with verbs in AD is due in part to altered activation of the large-scale neural network that supports verb processing. 相似文献
120.
Shigemitsu Iwai MD Kei Torikai MD Chris M. Coppin MD Yoshiki Sawa MD 《Journal of artificial organs》2007,10(1):29-35
Currently used bioprosthetic valves have several limitations such as calcification and functional deterioration, and revitalization
through cellular ingrowth is impossible. To overcome these obstacles, we have developed a minimally immunogenic tissue-engineered
valve that consists of an unfixed, decellularized porcine valve scaffold capable of being spontaneously revitalized in vivo
after implantation. Porcine aortic root tissue was decellularized using detergents such as sodium lauryl sulfate and Triton
X-100. The porcine valve was treated very gently and plenty of time was allowed for constituents to diffuse in and out of
the matrix. In a preliminary study, a piece of decellularized porcine valve tissue was implanted into the rat subdermal space
for 14 and 60 days and the structural integrity and calcification were evaluated. As an in vivo valve replacement model, the
decellularized porcine valve was implanted in the pulmonary valve position in dogs and functional and histological evaluation
was performed after 1, 2, and 6 months. Histological examination showed that the newly developed detergent treatment effectively
removed cellular debris from the porcine aortic tissue. Decellularized porcine valve tissue implanted subdermally in rats
showed minimal inflammatory cell infiltration and calcification. In the valve replacement model, spontaneous reendothelialization
and repopulation of the medial cells were observed within 2 months, and good valve function without regurgitation was observed
by echocardiography up to 6 months. The minimally immunogenic decellularized porcine valve proved effective in mitigating
postimplant calcification and provided a suitable matrix for revitalizing prostheses through in situ recellularization, cellular
ingrowth, and tissue remodeling. 相似文献