全文获取类型
收费全文 | 4079篇 |
免费 | 343篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 36篇 |
儿科学 | 154篇 |
妇产科学 | 87篇 |
基础医学 | 686篇 |
口腔科学 | 89篇 |
临床医学 | 377篇 |
内科学 | 898篇 |
皮肤病学 | 65篇 |
神经病学 | 443篇 |
特种医学 | 87篇 |
外科学 | 368篇 |
综合类 | 12篇 |
一般理论 | 1篇 |
预防医学 | 449篇 |
眼科学 | 95篇 |
药学 | 284篇 |
中国医学 | 5篇 |
肿瘤学 | 299篇 |
出版年
2024年 | 3篇 |
2023年 | 48篇 |
2022年 | 32篇 |
2021年 | 114篇 |
2020年 | 96篇 |
2019年 | 121篇 |
2018年 | 129篇 |
2017年 | 119篇 |
2016年 | 117篇 |
2015年 | 136篇 |
2014年 | 142篇 |
2013年 | 194篇 |
2012年 | 357篇 |
2011年 | 367篇 |
2010年 | 187篇 |
2009年 | 167篇 |
2008年 | 262篇 |
2007年 | 311篇 |
2006年 | 234篇 |
2005年 | 251篇 |
2004年 | 266篇 |
2003年 | 218篇 |
2002年 | 220篇 |
2001年 | 26篇 |
2000年 | 21篇 |
1999年 | 27篇 |
1998年 | 32篇 |
1997年 | 26篇 |
1996年 | 22篇 |
1995年 | 19篇 |
1994年 | 17篇 |
1993年 | 17篇 |
1992年 | 18篇 |
1991年 | 17篇 |
1990年 | 7篇 |
1989年 | 8篇 |
1988年 | 9篇 |
1987年 | 10篇 |
1986年 | 6篇 |
1985年 | 5篇 |
1984年 | 8篇 |
1983年 | 5篇 |
1982年 | 6篇 |
1975年 | 3篇 |
1971年 | 3篇 |
1970年 | 2篇 |
1969年 | 3篇 |
1968年 | 2篇 |
1967年 | 2篇 |
1965年 | 6篇 |
排序方式: 共有4435条查询结果,搜索用时 15 毫秒
31.
32.
Woo PC Lau SK Wong BH Tsoi HW Fung AM Kao RY Chan KH Peiris JS Yuen KY 《Journal of clinical microbiology》2005,43(7):3054-3058
The use of recombinant severe acute respiratory syndrome-coronavirus (SARS-CoV) nucleocapsid protein (N) enzyme-linked immunosorbent assay (ELISA)-based antibody and antigen tests for diagnosis of SARS-CoV infections have been widely reported. However, no recombinant SARS-CoV spike protein (S)-based ELISA is currently available. In this article, we describe the problems and solutions of setting up the recombinant SARS-CoV S-based ELISA for antibody detection. The SARS-CoV S-based immunoglobulin M (IgM) and IgG ELISAs were evaluated and compared with the corresponding N-based ELISA for serodiagnosis of SARS-CoV pneumonia, using sera from 148 healthy blood donors who donated blood 3 years ago as controls and 95 SARS-CoV pneumonia patients in Hong Kong. Results obtained by the recombinant S (rS)-based IgG ELISA using the regenerated S prepared by dialysis with decreasing concentrations of urea or direct addition of different coating buffers, followed by addition of different regeneration buffer, identified 4 M urea and 1 M sarcosine for plate coating and no regeneration buffer as the most optimal conditions for antibody detection. The specificities of the S-based ELISA for IgG and IgM detection were 98.6% and 93.9%, with corresponding sensitivities of 58.9% and 74.7%, respectively. The sensitivity of the rN IgG ELISA (94.7%) is significantly higher than that of the rS IgG ELISA (P < 0.001), whereas the sensitivity of the rS IgM ELISA is significantly higher than that of the rN IgM ELISA (55.2%) (P < 0.01). An ELISA for detection of IgM against S and N could be more sensitive than one that detects IgM against N alone for serodiagnosis of SARS-CoV pneumonia. 相似文献
33.
Mario Cocco Cristiana Bellan Roxane Tussiwand Davide Corti Elisabetta Traggiai Stefano Lazzi Susanna Mannucci Lucio Bronz Nazzareno Palummo Chiara Ginanneschi Piero Tosi Antonio Lanzavecchia Markus G. Manz Lorenzo Leoncini 《The American journal of pathology》2008,173(5):1369-1378
Recent studies suggest that Epstein-Barr virus (EBV) can infect naïve B cells, driving them to differentiate into resting memory B cells via the germinal center reaction. This hypothesis has been inferred from parallels with the biology of normal B cells but has never been proven experimentally. Rag2−/− γc−/− mice that were transplanted with human CD34+ cord blood cells as newborns were recently shown to develop human B, T, and dendritic cells, constituting lymphoid organs in situ. Here we used this model to better define the strategy of EBV infection of human B cells in vivo and to compare this model system with different conditions of EBV infection in humans. Our results support the model of EBV persistence in vivo in cases that were characterized by follicular hyperplasia and a relatively normal CD4+ and CD8+ T-cell distribution. Intriguingly, in cases that were characterized by nodular and diffuse proliferation with a preponderance of CD8+ T cells, similar to infectious mononucleosis, EBV still infects naïve B cells but also induces clonal expansion and ongoing somatic mutations without germinal center reactions. Our results reveal different strategies of EBV infection in B cells that possibly result from variations in the host immune response. Future experiments might allow understanding of the mechanisms responsible for persistent EBV infection and provide targets for more highly tailored therapeutic interventions. 相似文献
34.
Mauro Congia Fulvia Frau Rosanna Lampis Rita Frau Roberto Mele Francesco Cucca Francesco Muntoni Susanna Porcu Francesca Boi Licinio Contu Giorgio La Nasa Marina Mulargia Mario Pirastu Antonio Cao Stefano De Virgillis 《Tissue antigens》1992,39(2):78-83
This study characterizes by serological and molecular methods the HLA class I and class II alleles in a group of celiac disease children, their parents and a control group of Sardinian descent. We found the DR3-DQw2 haplotype in all patients which was, in almost all cases (84%), associated with the HLA-A30, B18, DR3, DRw52, DQw2 extended haplotype named "Sardinian haplotype" because of its frequency (12-15%) in this Caucasian population. This is the first time that this DQw2-linked haplotype has been reported with such a high frequency in CD. However, no different distribution of "Sardinian haplotype" was found comparing CD patients with 91 haplotyped DQw2-positive controls. This finding indicates that the DQw2 antigen in Sardinians is almost always associated with the A30, B18, DR3, DRw52, DQw2 extended haplotype. The DQA1 and DQB1 second exon sequence analysis of the B18,DR3 and B8,DR3 haplotypes showed the DQA1*0501 and DQB1*0201 alleles which shared the already published sequences. DPB1 subtyping showed the DPB1*0301 allele more frequently (p less than 0.005) in CD patients but this difference was no longer significant when patients and controls, both heterozygous for the DR3-DQw2 haplotype, were compared. We suggest that the divergent HLA extended haplotypes and DP allele associated with CD, described in different Caucasian populations, can be explained by the particular DQw2 linkage disequilibrium in each population. 相似文献
35.
Granulocyte superoxide production by different stimuli was studied in 14 patients suffering from rheumatoid arthritis, and in four cases defective (O
2
–
generation was shown. The effect of two chemically related drugs, such as indomethacin and oxamethacin, was also evaluated, since we have previously investigated the action of antiinflammatory agents on cell locomotion. Indomethacin did not affect O
2
–
production, whereas oxamethacin reduced significantly superoxide generation in PMNs from all subjects tested. Moreover, the extent of the effect was dependent on the stimulant used, being larger when the activation of O
2
–
generating system was induced by opsonized zymosan. 相似文献
36.
Alicia Aguilar-Martínez Marina Bosque-Prous Helena Gonzlez-Casals Ester Colillas-Malet Susanna Puigcorb Laura Esquius Albert Espelt 《Nutrients》2021,13(5)
Adolescence is a critical period in the consolidation of healthy lifestyles that can last into adulthood. To analyze changes in food consumption and eating behaviors in high-school adolescents during the first confinement, a cross-sectional study was conducted at the end of confinement in Spain. Changes in the frequency or quantity of consumption of different types of food and food-related behaviors were analyzed. Socioeconomic and health-related variables were also considered. To determine whether dietary changes were related to socioeconomic position (SEP), Poisson regression models with robust variance were estimated. Overall, there were some changes towards a healthier diet such as an increase in fruit consumption (38.9%) and a decrease in the consumption of soft drinks (49.8%), sweets and pastries (39.3%), and convenience foods (49.2%). Some changes, however, were related to less healthy behaviors, such as a more irregular pattern of meal distribution (39.9%) or an increase in snacking between meals (56.4%). Changes towards less healthy eating were also related to students’ SEP. The risk of worsening the diet was found to be 21% higher in adolescents from a more disadvantaged SEP. Future public policies could be adapted to avoid increasing nutritional and health inequalities. 相似文献
37.
38.
Lorente Nicolas Sherriff Nigel Panochenko Oksana Marcus Ulrich Dutarte Maria Kuske Matthias Aussó Susanna Huber Jörg Krone Michael Schink Susanne Barbara Cawley Caoimhe Casabona Jordi Folch Cinta 《Journal of community health》2021,46(3):545-556
Journal of Community Health - Little is known about Community Health Workers (CHWs) who work in non-clinical settings to provide sexual health support around HIV, viral hepatitis, and other... 相似文献
39.
V Susanna A Loffreda M G Matera R Servodio A Filippelli A Santagata C Montanaro N Carapella E Marmo 《International journal of tissue reactions》1990,12(1):59-65
We have investigated the effect of inhaled adenosine on bronchomotor tone in 16 healthy and 24 allergic and non-allergic bronchopathic subjects. We determined the inhaled adenosine dose-response curves after no treatment and after treatment with aminophylline (240 mg in 10 min), reproterol (90 mcg in 2 min) and salbutamol (100 mcg in 2 min) administered intravenously 15 min before adenosine and reproterol (500 mcg) and salbutamol (200 mcg) administered by inhalation from a metered aerosol 30 min before adenosine on separate days. Without prior treatment, inhaled adenosine caused bronchoconstriction in both groups of subjects (normal, and atopic and non-atopic asthmatic ones), but the peripheral airways revealed only a moderate change in normal subjects. Aminophylline caused a greater inhibition of adenosine bronchoconstriction than did reproterol. These results suggest that inhaled adenosine bronchoconstriction involved purinergic transmission and that it is mediated via a P1/Ri (A-1/R1) receptor. Aminophylline is a potent antagonist at purinoceptor level. Reproterol inhibits bronchoconstriction by a mechanism independent of its effect on beta-adrenergic receptors. Because salbutamol, i.e. a beta 2-agonist bronchodilator, did not inhibit adenosine-induced bronchoconstriction (or very nearly so), our results support the view that reproterol antagonizes P1/Ri (A1/R1) tracheobronchial receptors. 相似文献
40.
Susanna Jernelöv Erik Forsell Henrietta Westman Ylva Eriksson Dufva Nils Lindefors Viktor Kaldo Martin Kraepelien 《Journal of sleep research》2023,32(2):e13759
Cognitive behavioural therapy for insomnia is efficacious and recommended for insomnia, but availability is scarce. Cognitive behavioural therapy for insomnia self-help interventions could increase availability, especially if unguided. Optimizing cognitive behavioural therapy for insomnia methods and system user-friendliness, we developed a short, digital, self-help programme—FastAsleep—based on the behavioural components of sleep restriction and stimulus control. This study investigated its feasibility and preliminary effects. Thirty media-recruited participants with moderate to severe insomnia were assessed via telephone before using FastAsleep for 4 weeks, and were interviewed afterwards. Self-ratings with web questionnaires were conducted at screening, pre-, mid- and post-treatment, and at 3-month follow-up. Primary outcomes were feasibility (credibility, adherence, system user-friendliness and adverse effects), and secondary outcomes were changes in symptom severity (insomnia, depression and anxiety). Adherence was generally high, participants' feasibility ratings were favourable, and adverse effects matched previously reported levels for cognitive behavioural therapy for insomnia. Symptoms of insomnia decreased after the treatment period (Hedge's g = 1.79, 95% confidence interval = 1.20–2.39), as did symptoms of depression and anxiety. FastAsleep can be considered feasible and promising for alleviating insomnia symptoms among patients fit for self-care. Future controlled trials are needed to establish the efficacy of FastAsleep and its suitability in a stepped care model. 相似文献