全文获取类型
收费全文 | 1306篇 |
免费 | 95篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 13篇 |
儿科学 | 32篇 |
妇产科学 | 24篇 |
基础医学 | 203篇 |
口腔科学 | 3篇 |
临床医学 | 128篇 |
内科学 | 278篇 |
皮肤病学 | 6篇 |
神经病学 | 154篇 |
特种医学 | 30篇 |
外科学 | 225篇 |
综合类 | 11篇 |
一般理论 | 1篇 |
预防医学 | 59篇 |
眼科学 | 25篇 |
药学 | 61篇 |
中国医学 | 1篇 |
肿瘤学 | 148篇 |
出版年
2023年 | 4篇 |
2022年 | 14篇 |
2021年 | 33篇 |
2020年 | 11篇 |
2019年 | 15篇 |
2018年 | 27篇 |
2017年 | 21篇 |
2016年 | 23篇 |
2015年 | 37篇 |
2014年 | 39篇 |
2013年 | 54篇 |
2012年 | 66篇 |
2011年 | 68篇 |
2010年 | 36篇 |
2009年 | 31篇 |
2008年 | 61篇 |
2007年 | 78篇 |
2006年 | 68篇 |
2005年 | 73篇 |
2004年 | 58篇 |
2003年 | 54篇 |
2002年 | 56篇 |
2001年 | 51篇 |
2000年 | 36篇 |
1999年 | 32篇 |
1998年 | 16篇 |
1997年 | 15篇 |
1996年 | 13篇 |
1995年 | 15篇 |
1994年 | 12篇 |
1993年 | 15篇 |
1992年 | 27篇 |
1991年 | 26篇 |
1990年 | 18篇 |
1989年 | 24篇 |
1988年 | 25篇 |
1987年 | 23篇 |
1986年 | 11篇 |
1985年 | 27篇 |
1984年 | 17篇 |
1983年 | 7篇 |
1982年 | 5篇 |
1980年 | 5篇 |
1979年 | 6篇 |
1978年 | 8篇 |
1977年 | 11篇 |
1976年 | 7篇 |
1975年 | 6篇 |
1973年 | 5篇 |
1972年 | 3篇 |
排序方式: 共有1402条查询结果,搜索用时 78 毫秒
31.
Andrew G. Matthew Orit Raz Kristen L. Currie Alyssa S. Louis Haiyan Jiang Tal Davidson 《Journal of psychosocial oncology》2018,36(2):159-174
Objective: To quantify distress in men treated with radical prostatectomy (RP) or active surveillance (AS). Methods: In a retrospective cross-sectional design, we assessed men through questionnaire and investigator-designed questions. Results: RP patients worried more about cancer spread than AS patients. RP patients were influenced by friends for treatment decision, whereas AS patients were influenced by urologists. RP group report declines in intimacy and instrumental. AS men worried more about future health and dying than post-RP men. Conclusion: Fear of disease progression may be a motivating factor in choosing RP. AS patients adhere to their treatment decision in spite of distress. 相似文献
32.
23S rRNA base pair 2057-2611 determines ketolide susceptibility and fitness cost of the macrolide resistance mutation 2058A-->G
下载免费PDF全文
![点击此处可从《Proceedings of the National Academy of Sciences of the United States of America》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Pfister P Corti N Hobbie S Bruell C Zarivach R Yonath A Böttger EC 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(14):5180-5185
The 23S rRNA A2058G alteration mediates macrolide, lincosamide, and streptogramin B resistance in the bacterial domain and determines the selectivity of macrolide antibiotics for eubacterial ribosomes, as opposed to eukaryotic ribosomes. However, this mutation is associated with a disparate resistance phenotype: It confers high-level resistance to ketolides in mycobacteria but only marginally affects ketolide susceptibility in streptococci. We used site-directed mutagenesis of nucleotides within domain V of 23S rRNA to study the molecular basis for this disparity. We show that mutational alteration of the polymorphic 2057-2611 base pair from A-U to G-C in isogenic mutants of Mycobacterium smegmatis significantly affects susceptibility to ketolides but does not influence susceptibility to other macrolide antibiotics. In addition, we provide evidence that the 2057-2611 polymorphism determines the fitness cost of the 23S rRNA A2058G resistance mutation. Supported by structural analysis, our results indicate that polymorphic nucleotides mediate the disparate phenotype of genotypically identical resistance mutations and provide an explanation for the large species differences in the epidemiology of defined drug resistance mutations. 相似文献
33.
34.
Chazan B Colodner R Teitler N Chen Y Raz R 《American journal of infection control》2008,36(6):436-438
Health care workers (HCWs) are susceptible to hospital acquired varicella zoster virus (VZV). We evaluated seroprevalence and predictive value of a history of varicella disease (VD) with VZV serology in HCWs in northern Israel. A total of 200 HCWs were enrolled. A high rate of seropositivity for VZV-IgG was found: 98.5% seropositive and only 1.5% seronegative. A positive history of VD was an excellent predictor for the presence of VZV-IgG; however, a negative history of VD does not rule out the presence of VZV-IgG. 相似文献
35.
Dyachenko P Ziv M Raz R Chazan B Lev A Rozenman D 《European Journal of Internal Medicine》2005,16(8):610-611
Cat scratch disease (CSD) is typically a self-limited regional lymphadenopathy in children and young adults that is caused by Bartonella henselae. The majority of CSD cases resolve spontaneously; however, many systemic complications have been described. We report an unusual case of CSD presenting as an epitrochlear arm mass and complicated by encephalopathy. Identification of B. henselae DNA in the affected lymph node and cerebrospinal fluid confirmed the diagnosis of CSD. Systemic antibiotic therapy was administered and the patient improved without any neurological deficit. 相似文献
36.
Fujioka K Brazg RL Raz I Bruce S Joyal S Swanink R Pans M 《Diabetes, obesity & metabolism》2005,7(1):28-39
AIM: The efficacy, dose-response relationships and safety of an extended-release formulation of metformin (Glucophage) XR) were evaluated in two double-blind, randomized, placebo-controlled studies of 24 and 16 weeks' duration, in patients with inadequate glycaemic control despite diet and exercise. Protocol 1 provided an evaluation of metformin XR at a commonly used dosage. Protocol 2 evaluated different dosages of metformin XR. METHODS: In Protocol 1, 240 patients were randomized to receive metformin XR 1000 mg once daily. or placebo in a 2:1 ratio for 12 weeks (patients could receive metformin XR 1500 mg during weeks 12-24 if required). In Protocol 2, 742 patients were randomized to receive metformin XR 500 mg once daily, 1000 mg once daily, 1500 mg once daily, 2000 mg once daily, 1000 mg twice daily or placebo for 16 weeks. The primary endpoint in each study was the change from baseline in HbA(1C) at 12 weeks (Protocol 1) or 16 weeks (Protocol 2). RESULTS: Metformin XR reduced HbA(1C) in Protocol 1, with mean treatment differences for 1000 mg once daily vs. placebo of -0.7% at 12 weeks and -0.8% at 24 weeks (p < 0.001 for each). In Protocol 2, a clear dose-response relationship was evident at doses up to 1500 mg, with treatment differences vs. placebo of -0.6% (500 mg once daily), -0.7% (1000 mg once daily), -1.0% (1500 mg once daily) and -1.0% (2000 mg once daily). The efficacy of metformin XR 2000 mg once daily and 1000 mg twice daily were similar (mean treatment differences vs. placebo in HbA(1C) were -1.0% and -1.2%, respectively). More patients achieved HbA(1C) < 7.0% with metformin XR vs. placebo in Protocol 1 (29% vs. 14% at 12 weeks) and with once-daily metformin XR in Protocol 2 (up to 36% vs. 10% at 16 weeks). No significant changes in fasting insulin or body weight occurred. Total and low-density lipoprotein (LDL)-cholesterol improved (p < 0.05-p < 0.001) in metformin XR groups in Protocol 2. Metformin XR was well tolerated; gastrointestinal side effects were more common with metformin XR vs. placebo, but few patients withdrew for this reason (1.3% vs. 1.3% in Protocol 1 and 1.6% vs. 0.9% in Protocol 2). CONCLUSIONS: Once-daily metformin XR presents an effective and well-tolerated therapeutic option for delivering metformin in a convenient manner, which supports good compliance with therapy. 相似文献
37.
Ofer Beharier Romina Plitman Mayo Tal Raz Kira Nahum Sacks Letizia Schreiber Yael Suissa-Cohen Rony Chen Rachel Gomez-Tolub Eran Hadar Rinat Gabbay-Benziv Yuval Jaffe Moshkovich Tal Biron-Shental Gil Shechter-Maor Sivan Farladansky-Gershnabel Hen Yitzhak Sela Hedi Benyamini-Raischer Nitzan D. Sela Debra Goldman-Wohl Ziv Shulman Ariel Many Haim Barr Simcha Yagel Michal Neeman Michal Kovo 《The Journal of clinical investigation》2021,131(13)
BACKGROUNDThe significant risks posed to mothers and fetuses by COVID-19 in pregnancy have sparked a worldwide debate surrounding the pros and cons of antenatal SARS-CoV-2 inoculation, as we lack sufficient evidence regarding vaccine effectiveness in pregnant women and their offspring. We aimed to provide substantial evidence for the effect of the BNT162b2 mRNA vaccine versus native infection on maternal humoral, as well as transplacentally acquired fetal immune response, potentially providing newborn protection.METHODSA multicenter study where parturients presenting for delivery were recruited at 8 medical centers across Israel and assigned to 3 study groups: vaccinated (n = 86); PCR-confirmed SARS-CoV-2 infected during pregnancy (n = 65), and unvaccinated noninfected controls (n = 62). Maternal and fetal blood samples were collected from parturients prior to delivery and from the umbilical cord following delivery, respectively. Sera IgG and IgM titers were measured using the Milliplex MAP SARS-CoV-2 Antigen Panel (for S1, S2, RBD, and N).RESULTSThe BNT162b2 mRNA vaccine elicits strong maternal humoral IgG response (anti-S and RBD) that crosses the placenta barrier and approaches maternal titers in the fetus within 15 days following the first dose. Maternal to neonatal anti-COVID-19 antibodies ratio did not differ when comparing sensitization (vaccine vs. infection). IgG transfer ratio at birth was significantly lower for third-trimester as compared with second trimester infection. Lastly, fetal IgM response was detected in 5 neonates, all in the infected group.CONCLUSIONAntenatal BNT162b2 mRNA vaccination induces a robust maternal humoral response that effectively transfers to the fetus, supporting the role of vaccination during pregnancy.FUNDINGIsrael Science Foundation and the Weizmann Institute Fondazione Henry Krenter. 相似文献
38.
Pleun Hombrink Yotam Raz Michel G. D. Kester Renate de Boer Bianca Weißbrich Peter A. von dem Borne Dirk H. Busch Ton N. M. Schumacher J. H. Frederik Falkenburg Mirjam H. M. Heemskerk 《European journal of immunology》2013,43(11):3038-3050
The low frequency of antigen‐specific naïve T cells has challenged numerous laboratories to develop various techniques to study the naïve T‐cell repertoire. Here, we combine the generation of naïve repertoire‐derived antigen‐specific T‐cell lines based on MHC‐tetramer staining and magnetic‐bead enrichment with in‐depth functional assessment of the isolated T cells. Cytomegalovirus (CMV) specific T‐cell lines were generated from seronegative individuals. Generated T‐cell lines consisted of a variety of immunodominant CMV‐epitope‐specific oligoclonal T‐cell populations restricted to various HLA‐molecules (HLA‐A1, A2, B7, B8, and B40), and the functional and structural avidity of the CMV‐specific T cells was studied. Although all CMV‐specific T cells were isolated based on their reactivity toward a specific peptide‐MHC complex, we observed a large variation in the functional avidity of the MHC‐tetramer positive T‐cell populations, which correlated with the structural avidity measured by the recently developed Streptamer koff‐rate assay. Our data demonstrate that MHC‐tetramer staining is not always predictive for specific T‐cell reactivity, and challenge the sole use of MHC‐tetramers as an indication of the peripheral T‐cell repertoire, independent of the analysis of functional activity or structural avidity parameters. 相似文献
39.
40.