全文获取类型
收费全文 | 41865篇 |
免费 | 4372篇 |
国内免费 | 1299篇 |
专业分类
耳鼻咽喉 | 841篇 |
儿科学 | 938篇 |
妇产科学 | 555篇 |
基础医学 | 8266篇 |
口腔科学 | 575篇 |
临床医学 | 3354篇 |
内科学 | 6874篇 |
皮肤病学 | 616篇 |
神经病学 | 3546篇 |
特种医学 | 997篇 |
外国民族医学 | 7篇 |
外科学 | 3113篇 |
综合类 | 4482篇 |
现状与发展 | 12篇 |
一般理论 | 1篇 |
预防医学 | 2883篇 |
眼科学 | 644篇 |
药学 | 4286篇 |
17篇 | |
中国医学 | 1859篇 |
肿瘤学 | 3670篇 |
出版年
2024年 | 64篇 |
2023年 | 1032篇 |
2022年 | 1157篇 |
2021年 | 2252篇 |
2020年 | 2061篇 |
2019年 | 1714篇 |
2018年 | 1636篇 |
2017年 | 1750篇 |
2016年 | 1762篇 |
2015年 | 1779篇 |
2014年 | 2512篇 |
2013年 | 3452篇 |
2012年 | 2157篇 |
2011年 | 2297篇 |
2010年 | 1833篇 |
2009年 | 1860篇 |
2008年 | 1770篇 |
2007年 | 1672篇 |
2006年 | 1605篇 |
2005年 | 1301篇 |
2004年 | 1180篇 |
2003年 | 1045篇 |
2002年 | 931篇 |
2001年 | 830篇 |
2000年 | 660篇 |
1999年 | 589篇 |
1998年 | 492篇 |
1997年 | 447篇 |
1996年 | 396篇 |
1995年 | 458篇 |
1994年 | 416篇 |
1993年 | 342篇 |
1992年 | 335篇 |
1991年 | 357篇 |
1990年 | 257篇 |
1989年 | 253篇 |
1988年 | 246篇 |
1987年 | 247篇 |
1986年 | 240篇 |
1985年 | 332篇 |
1984年 | 330篇 |
1983年 | 206篇 |
1982年 | 269篇 |
1981年 | 183篇 |
1980年 | 161篇 |
1979年 | 155篇 |
1978年 | 92篇 |
1977年 | 83篇 |
1976年 | 78篇 |
1975年 | 51篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
《Vaccine》2022,40(30):4038-4045
PurposeAs protection from COVID-19 following two doses of the BNT162b2 vaccine showed a time dependent waning, a third (booster) dose was administrated. This study aims to compare the antibody response following the third dose versus the second and to evaluate post-booster seroconversion.MethodsA prospective observational study conducted in Maccabi Healthcare Services. Serial SARS-CoV-2 Spike IgG tests, 1,2,3 and 6 months following the second vaccine dose and one month following the third were obtained. Neutralizing antibody levels were measured in a subset of participants. Per individual SARS-CoV-2 Spike IgG titer ratios were calculated one month after the booster administration compared to titers one month following the second dose and prior to booster.ResultsAmong 110 participants, 56 (51%) were women. Mean age was 61.7 ± 1.9 years and 66 (60%) were immunocompromised. One month after third dose, IgG titers were induced 7.83 (95 %CI 5.25–11.67) folds and 2.40 (95 %CI 1.90–3.03) folds compared to one month after the second, in the immunocompromised and immunocompetent groups, respectively. Of the 17 immunocompromised participants who were seronegative after the second dose, 4 (24%) became seropositive following the third. Comparing the titers prior to the third dose, an increase of 50.7 (95 %CI 32.5–79.1) fold in the immunocompromised group and 25.7 (95 %CI 19.1–34.7) fold in and immunocompetent group, was observed.ConclusionA third BNT162b2 vaccine elicited robust humoral response, superior to the response observed following the second, among immunocompetent and immunocompromised individuals. 相似文献
2.
《Revista brasileira de otorrinolaringologia (English ed.)》2022,88(4):621-624
ObjectivesRecurrent Aphthous Stomatitis (RAS) a chronic idiopathic oral mucosal disease. But yet the etiology and pathogenesis of RAS are not exactly known, it is thought that inflammation play an important role in the pathogenesis. The aim of this study is to demonstrate the role of systemic inflammation among the possible etiological factors of RAS and to find the possible diagnostic correlation between Systemic Immune Inflammation Index (SII).MethodsPatients who were consulted the otolaryngology outpatient clinic and diagnosed with RAS between 2019–2021 were retrospectively analyzed. Neutrophil/Lymphocyte Ratio (NLR), Platelet/Lymphocyte Ratio (PLR) and SII values were calculated based on the results of complete blood count. Demographic and hematological parameters between control and RAS groups were compared. The statistical significance level was considered as <0.05.ResultsThere was no statistically significant difference between the control and RAS groups in terms of sex and age distributions (p = 0.566 and p = 0.173, respectively). SII, NLR and PLR values were significantly higher in the RAS group compared to the controls (p < 0.001, p < 0.001 and p = 0.001, respectively). A very strong correlation between SII and NLR, moderately strong correlation between SII and PLR and moderate correlation between NLR and PLR values were detected (respectively ρ: 0.813, 0.719, 0.532; p-values <0.001).ConclusionSII, NLR and PLR has significantly higher levels in the RAS group compared to the control group, that it supports the role of systemic inflammation in the etiopathogenesis of RAS. In addition, the results show that SII is a valuable marker for inflammation.Level of evidence4. 相似文献
3.
《Revista de gastroenterologia de Mexico》2022,87(1):52-58
IntroductionThe sofosbuvir-velpatasvir (SOF/VEL) combination is a direct-acting antiviral therapy that is authorized and available in Mexico, making the performance of a real-world multicenter study that evaluates the sustained virologic response at 12 weeks post-treatment a relevant undertaking.MethodsA retrospective review of the case records of 241 patients seen at 20 hospitals in Mexico was conducted to assess hepatitis C treatment with the SOF/VEL combination (n = 231) and the sofosbuvir/velpatasvir/ribavirin (SOF/VEL/RBV) combination (n = 10). The primary efficacy endpoint was the percentage of patients that achieved SVR at 12 weeks after the end of treatment.ResultsOverall SVR was 98.8% (95% CI 97.35-100%). Only three patients did not achieve SVR, two of whom had cirrhosis and a history of previous treatment with peg-IFN. Of the subgroups analyzed, all the patients with HIV coinfection, three patients with genotype 3, and the patients treated with the SOF/VEL/RBV combination achieved SVR. The subgroups with the lower success rates were patients that were treatment-experienced (96.8%) and patients with F1 fibrosis (95.5%). The most frequent adverse events were fatigue, headache, and insomnia. No serious adverse events were reported.ConclusionTreatments with SOF/VEL and SOF/VEL/RBV were highly safe and effective, results coinciding with those of other international real-world studies. 相似文献
4.
5.
《Vaccine》2022,40(31):4105-4115
The etiologic agents of visceral leishmaniasis are Leishmania infantum and Leishmania donovani. Despite the variety of drugs available to treat leishmaniasis, most lead to serious adverse effects, and resistance to these drugs has been reported. Currently, no leishmaniasis vaccine is available for humans. That is why the group developed transgenic L. infantum promastigote lines, which express toxic proteins after differentiation into amastigotes. That is why group developed the pFL-AMA plasmid and transfected it into L. Infantum promastigotes. This plasmid was expressed only in the amastigote form of the parasite. Sequences encoding toxic proteins (active bovine trypsin and egg avidin) were inserted in this plasmid, and the transfected parasites died after the differentiation process. In this study, two immunization protocols were performed in BALB/c mice: prime and prime-boost immunization prior to challenge with the wild-type L. infantum (WT). The parasite burdens in the spleen, liver, and bone marrow were evaluated to verify immunological protection. Histopathological analysis of the spleen and liver and the humoral immune response were also performed. The data showed that the parasite burden was reduced in prime-boosted mice in the spleen, liver, and bone marrow, indicating that mice immunized with two doses of the transfected parasites were satisfactorily protected. High levels of IgG, IgG1, and IgG2a antibodies were observed, as well as the presence of anti-inflammatory cytokine Interleukine-10 and pro-inflammatory cytokine Tumor Necrosis Factor-α (TNF-α) and Interferon-γ (IFN – γ) suggesting a Th1/Th2 mix response, in addition to the presence of multinucleated giant cells in the spleen and lymphocyte infiltration in the liver. Therefore, L. infantum transfected with a toxic plasmid is an excellent vaccine candidate against visceral leishmaniasis and the application of a boost before the challenge promotes greater protection against WT L. infantum infection. 相似文献
6.
7.
目的 研究社区获得性肺炎(community acquired pneumonia,CAP)患儿血清维生素A(vitamin A,VA)水平及与免疫功能的相关性,为肺炎病情评估提供一定参考。方法 以入住新乡医学院第一附属医院PICU的63例重度社区获得性肺炎(severe community acquired pneumonia, SCAP)患儿(SCAP组)、普通儿科病区的30例轻度社区获得性肺炎(mild community acquired pneumonia, MCAP)患儿(MCAP组),以及同期体检的30名健康儿童(对照组)为研究对象,检测其血清中VA和免疫球蛋白(immunoglobulin,Ig)G、IgA、IgM水平,及SCAP组体内T淋巴细胞亚群(总T淋巴细胞、CD4、CD8、CD4/CD8),并对SCAP组体内VA水平及以上指标的相关性进行分析。结果 3组性别和年龄差异无统计学意义;血清中VA的平均含量分别为0.36、0.25和0.19 mg/L,CAP组VA的含量较对照组明显降低,且SCAP组明显低于MCAP组( <0.05)。根据WHO推荐的VA诊断标准,3组VA临床缺乏/亚临床缺乏率分别为10.00%、36.67%和61.90%,差异有统计学意义( <0.05)。CAP组血清中Ig水平较对照组明显降低,且SCAP组明显低于MCAP组( <0.05)。SCAP组血中总T淋巴细胞、CD4、CD8和CD4/CD8的平均水平分别为53.28%、30.26%、20.24%和1.59;分析VA水平与免疫相关指标关系发现VA水平与Ig(IgG、IgA、IgM)水平、总T淋巴细胞、CD4呈正相关,与CD8水平不相关。结论 肺炎患儿血清VA水平与病情严重程度及机体免疫功能相关。 相似文献
8.
9.
Robert J. Motzer MD David F. McDermott MD Bernard Escudier MD Mauricio Burotto MD Toni K. Choueiri MD Hans J. Hammers MD PhD Philippe Barthélémy MD PhD Elizabeth R. Plimack MD Camillo Porta MD Saby George MD Thomas Powles MD Frede Donskov MD PhD Howard Gurney MD Christian K. Kollmannsberger MD Marc-Oliver Grimm MD Carlos Barrios MD Yoshihiko Tomita MD PhD Daniel Castellano MD Viktor Grünwald MD PhD Brian I. Rini MD M. Brent McHenry PhD Chung-Wei Lee MD PhD Jennifer McCarthy MA Flavia Ejzykowicz PhD Nizar M. Tannir MD 《Cancer》2022,128(11):2085-2097
10.