全文获取类型
收费全文 | 16090篇 |
免费 | 1211篇 |
国内免费 | 578篇 |
专业分类
耳鼻咽喉 | 66篇 |
儿科学 | 180篇 |
妇产科学 | 160篇 |
基础医学 | 810篇 |
口腔科学 | 596篇 |
临床医学 | 1561篇 |
内科学 | 2962篇 |
皮肤病学 | 397篇 |
神经病学 | 527篇 |
特种医学 | 671篇 |
外科学 | 1565篇 |
综合类 | 1607篇 |
现状与发展 | 1篇 |
预防医学 | 822篇 |
眼科学 | 151篇 |
药学 | 4326篇 |
4篇 | |
中国医学 | 228篇 |
肿瘤学 | 1245篇 |
出版年
2024年 | 18篇 |
2023年 | 202篇 |
2022年 | 364篇 |
2021年 | 575篇 |
2020年 | 557篇 |
2019年 | 571篇 |
2018年 | 581篇 |
2017年 | 547篇 |
2016年 | 608篇 |
2015年 | 635篇 |
2014年 | 909篇 |
2013年 | 1687篇 |
2012年 | 921篇 |
2011年 | 966篇 |
2010年 | 766篇 |
2009年 | 728篇 |
2008年 | 722篇 |
2007年 | 745篇 |
2006年 | 598篇 |
2005年 | 612篇 |
2004年 | 500篇 |
2003年 | 473篇 |
2002年 | 398篇 |
2001年 | 330篇 |
2000年 | 278篇 |
1999年 | 208篇 |
1998年 | 199篇 |
1997年 | 219篇 |
1996年 | 146篇 |
1995年 | 165篇 |
1994年 | 141篇 |
1993年 | 143篇 |
1992年 | 125篇 |
1991年 | 131篇 |
1990年 | 101篇 |
1989年 | 105篇 |
1988年 | 98篇 |
1987年 | 106篇 |
1986年 | 80篇 |
1985年 | 88篇 |
1984年 | 91篇 |
1983年 | 66篇 |
1982年 | 62篇 |
1981年 | 48篇 |
1980年 | 48篇 |
1979年 | 42篇 |
1978年 | 39篇 |
1977年 | 28篇 |
1976年 | 34篇 |
1975年 | 18篇 |
排序方式: 共有10000条查询结果,搜索用时 11 毫秒
91.
Cedric Hirzel Arnaud G. L'Huillier Victor H. Ferreira Tina Marinelli Terrance Ku Matthew Ierullo Congrong Miao D. Scott Schmid Stephen Juvet Atul Humar Deepali Kumar 《American journal of transplantation》2021,21(6):2246-2253
Lung transplant recipients are at high risk for herpes zoster and preventive measures are a significant unmet need. We investigated the safety and immunogenicity of two doses of a recombinant zoster vaccine (RZV) in lung transplant recipients (≥50 years). We enrolled 50 patients of which 49 received at least one vaccine dose. Anti-glycoprotein E (gE) antibody levels (n = 43) increased significantly compared to baseline (median optical density [OD] 1.96; interquartile range [IQR]: 1.17–2.89) after the first (median OD 3.41, IQR 2.54–3.81, p < .0001) and second vaccine dose (median OD 3.63, IQR 3.39–3.86, p < .0001). gE-specific polyfunctional CD4+ T cell frequencies (n = 38) also increased from baseline (median 85 per 106 CD4+ T cells; IQR: 46–180) to the first (median 128 per 106 CD4+ T cells; IQR: 82–353; p = .023) and after the second dose (median 361 per 106 CD4+ T cells; IQR: 146–848; p < .0001). Tenderness (83.0%; 95%CI: 69.2–92.4%) and redness (31.9%; 95%CI: 19.1–47.1%) at injection site were common. One rejection episode within 3 weeks of vaccination was observed. This is the first study demonstrating that RZV was safe and elicited significant humoral and cell-mediated immunity in lung transplant recipients. RZV is a new option for the prevention of shingles in this population. 相似文献
92.
Cecilia Nakid-Cordero Sylvain Choquet Nicolas Gauthier Noureddine Balegroune Nadine Tarantino Véronique Morel Nadia Arzouk Sonia Burrel Géraldine Rousseau Frédéric Charlotte Martin Larsen Vincent Vieillard Brigitte Autran Véronique Leblond Amélie Guihot for the K-VIROGREF Study Group 《American journal of transplantation》2021,21(8):2846-2863
EBV-positive and EBV-negative posttransplant lymphoproliferative disorders (PTLDs) arise in different immunovirological contexts and might have distinct pathophysiologies. To examine this hypothesis, we conducted a multicentric prospective study with 56 EBV-positive and 39 EBV-negative PTLD patients of the K-VIROGREF cohort, recruited at PTLD diagnosis and before treatment (2013–2019), and compared them to PTLD-free Transplant Controls (TC, n = 21). We measured absolute lymphocyte counts (n = 108), analyzed NK- and T cell phenotypes (n = 49 and 94), and performed EBV-specific functional assays (n = 16 and 42) by multiparameter flow cytometry and ELISpot-IFNγ assays (n = 50). EBV-negative PTLD patients, NK cells overexpressed Tim-3; the 2-year progression-free survival (PFS) was poorer in patients with a CD4 lymphopenia (CD4+<300 cells/mm3, p < .001). EBV-positive PTLD patients presented a profound NK-cell lymphopenia (median = 60 cells/mm3) and a high proportion of NK cells expressing PD-1 (vs. TC, p = .029) and apoptosis markers (vs. TC, p < .001). EBV-specific T cells of EBV-positive PTLD patients circulated in low proportions, showed immune exhaustion (p = .013 vs. TC) and poorly recognized the N-terminal portion of EBNA-3A viral protein. Altogether, this broad comparison of EBV-positive and EBV-negative PTLDs highlight distinct patterns of immunopathological mechanisms between these two diseases and provide new clues for immunotherapeutic strategies and PTLD prognosis. 相似文献
93.
Charles Varnell Jr Lyndsay A. Harshman Laurie Smith Chunyan Liu Shiran Chen Samhar Al-Akash Gina-Marie Barletta Craig Belsha Paul Brakeman Abanti Chaudhuri Paul Fadakar Rouba Garro Caroline Gluck Jens Goebel David Kershaw Debora Matossian Corina Nailescu Hiren P. Patel Cozumel Pruette Saritha Ranabothu Nancy Rodig Jodi Smith Judith Sebestyen VanSickle Patricia Weng Lara Danziger-Isakov David K. Hooper Michael Seifert 《American journal of transplantation》2021,21(8):2740-2748
There are limited data on the impact of COVID-19 in children with a kidney transplant (KT). We conducted a prospective cohort study through the Improving Renal Outcomes Collaborative (IROC) to collect clinical outcome data about COVID-19 in pediatric KT patients. Twenty-two IROC centers that care for 2732 patients submitted testing and outcomes data for 281 patients tested for SARS-CoV-2 by PCR. Testing indications included symptoms and/or potential exposures to COVID-19 (N = 134, 47.7%) and/or testing per hospital policy (N = 154, 54.8%). Overall, 24 (8.5%) patients tested positive, of which 15 (63%) were symptomatic. Of the COVID-19-positive patients, 16 were managed as outpatients, six received non-ICU inpatient care and two were admitted to the ICU. There were no episodes of respiratory failure, allograft loss, or death associated with COVID-19. To estimate incidence, subanalysis was performed for 13 centers that care for 1686 patients that submitted all negative and positive COVID-19 results. Of the 229 tested patients at these 13 centers, 10 (5 asymptomatic) patients tested positive, yielding an overall incidence of 0.6% and an incidence among tested patients of 4.4%. Pediatric KT patients in the United States had a low estimated incidence of COVID-19 disease and excellent short-term outcomes. 相似文献
94.
Tobias Veit Dieter Munker Jürgen Barton Katrin Milger Teresa Kauke Bruno Meiser Sebastian Michel Michael Zoller Hans Nitschko Oliver T. Keppler Jürgen Behr Nikolaus Kneidinger 《American journal of transplantation》2021,21(10):3449-3455
Letermovir is a new antiviral drug approved for the prophylaxis of CMV infection in allogeneic stem cell transplants. The aim of the study was to assess the therapeutic efficacy of letermovir in difficult to treat CMV infections in lung transplant recipients. All lung transplant recipients between March 2018 and August 2020, who have been treated with letermovir for ganciclovir-resistant or refractory CMV infection were included in the study and analysed retrospectively. In total, 28 patients were identified. CMV disease was present in 15 patients (53.6%). In 23 patients (82.1%), rapid response was noticed, and CMV-viral load could be significantly decreased (>1 log10) after a median of 17 [14–27] days and cleared subsequently in all of these patients. Five patients (17.9%) were classified as non-responder. Thereof, development of a mutation of the CMV UL56 terminase (UL-56-Gen: C325Y) conferring letermovir resistance could be observed in three patients (60%). Common side effects were mild and mostly of gastrointestinal nature. Mild adjustments of the immunosuppressive drugs were mandatory upon treatment initiation with letermovir. In addition to other interventions, letermovir was effective in difficult to treat CMV infections in lung transplant recipients. However, in patients with treatment failure mutation conferring letermovir, resistance should be taken into account. 相似文献
95.
目的:分析抗结核药物导致的肝损伤(anti-tuberculosis drug-induced liver injury,ATB-DILI)患者基质金属蛋白酶类(matrix metalloproteinases,MMP)水平及其相关性。方法:采用回顾性研究方法,收集2019年6月至2020年6月昆明市第三人民医院收治的肺结核患者中发生ATB-DILI的98例患者作为病例组;选取同期门诊健康体检者30名作为对照组。采集研究对象晨起空腹静脉血6 ml,采用双抗体夹心法检测其MMP-1、MMP-2、MMP-7、MMP-9、MMP-13、MMP-14浓度。病例组研究对象根据ATB-DILI临床分型分为肝细胞损伤型(A组)、胆汁淤积型(B组)、肝血管损伤型(C组)、混合型(D组);根据ATB-DILI严重程度分为0级(无肝损伤)、1级(轻度肝损伤)、2级(中度肝损伤)、3级(重度肝损伤)、4级(急性肝功能衰竭)、5级(致命)。比较不同临床分型组及对照组研究对象MMP水平;分析MMP水平与ATB-DILI严重程度分级相关性。结果:按照ATB-DILI临床分型,病例组中A组有51例,B组有12例,C组有15例,D组有20例;根据ATB-DILI严重程度分级,病例组中1级有33例,2级有27例,3级有22例,4级有14例,5级有2例。A、B、C、D组及对照组MMP-1浓度分别为:(89.1±11.2)ng/ml、(32.3±6.3)ng/ml、(47.5±9.1)ng/ml、(55.2±11.1)ng/ml、(27.5±8.2)ng/ml;MMP-2浓度分别为:(8.2±2.1)ng/ml、(6.2±2.3)ng/ml、(15.5±1.8)ng/ml、(7.2±1.6)ng/ml、(3.2±1.3)ng/ml;MMP-9浓度分别为:36.1(25.9,47.3)ng/ml、11.3(5.1,20.6)ng/ml、14.1(6.1,21.3)ng/ml、15.3(3.8,28.1)ng/ml、6.4(2.8,8.6)ng/ml;MMP-14浓度分别为:5.2(2.8,7.5)ng/ml、6.0(3.6,8.9)ng/ml、11.2(5.2,17.4)ng/ml、4.0(1.8,6.2)ng/ml、2.8(1.4,4.3)ng/ml。A组MMP-1和MMP-9浓度明显升高,C组MMP-2和MMP-14浓度明显升高,差异均有统计学意义(F=7.983,P=0.031;H=9.979,P=0.041;F=9.381,P=0.010;H=10.555,P=0.032)。ATB-DILI严重程度1、2、3、4、5级患者MMP-9浓度分别为:16.2(13.2,19.3)ng/ml、21.5(18.4,23.6)ng/ml、24.3(20.6,27.1)ng/ml、30.3(25.1,35.3)ng/ml、38.5(33.9,43.1)ng/ml,与严重程度分级呈正相关(r=0.882,P=0.000)。结论:不同临床分型ATB-DILI患者MMP-1、MMP-2、MMP-9、MMP-14浓度有不同程度升高;MMP-9浓度与ATB-DILI严重程度呈正相关;MMP水平可能为ATB-DILI发生的影响因素。 相似文献
96.
The margination of a particle circulating in the blood stream has been analyzed. The contribution of buoyancy, hemodynamic forces, van der Waals, electrostatic and steric interactions between the circulating particle and the endothelium lining the vasculature has been considered. For practical applications, the contribution of buoyancy, hemodynamic forces and van der Waals interactions should be only taken into account, whilst the effect of electrostatic and steric repulsion becomes important only at very short distances from the endothelium (1–10 nm). The margination speed and the time for margination ts have been estimated as a function of the density of the particle relative to blood , the Hamaker constant A and radius R of the particle. A critical radius Rc exists for which the margination time ts has a maximum, which is influenced by both and A: the critical radius decreases as the relative density increases and the Hamaker constant decreases. Therefore, particles used for drug delivery should have a radius smaller than the critical value (in the range of 100 nm) to facilitate margination and interaction with the endothelium. While particles used as nanoharvesting agents in proteomics or genomics analysis should have a radius close to the critical value to minimize margination and increase their circulation time. 相似文献
97.
Linkage of cytotoxic agents to immunoglobulins 总被引:3,自引:0,他引:3
98.
99.
新型三唑苄胺类化合物体外抗真菌活性及构效关系 总被引:1,自引:0,他引:1
目的:研究23个1-[2-(N-甲基-N-取代苄基)氨基-2(2,4-二氟苯基)乙基]-1H-1,2,4-三唑类化合物的体外抗真菌活性,并初步探讨其构效关系。方法:选择8种临床致病真菌为试验菌,观察本类化合物对它们的体外抑菌作用,并与布替萘芬和益康唑作比较。结果和结论:所有目标化合物对8种试验真菌均有不同程度的抑制作用,大部分化合物对白念珠菌和近平滑念珠菌的活性明显高于布替萘芬;化合物2、13对新型隐球菌的活性是益康唑的64-128倍,化合物2、3、13、16对多数真菌显示较强活性。构效关系研究表明,苄胺类和氮唑类化合物的特征结构组合在一起,对某些真菌的抑菌活性起到了取长补短的作用;但苄基为萘苄时,对多数深部真菌活性较差。 相似文献
100.
活血通脉片对大鼠异丙肾上腺素心肌损伤的保护作用 总被引:3,自引:1,他引:2
目的:研究中药复方制剂活血通脉片(Huoxue TOngmai tablet,HXTMT)对异丙肾上腺素(isoproterenol,ISO)心肌损伤大鼠的保护作用,方法:用HXTMT给SD大鼠连续灌胃14d,第12日起动物sc ISO(48umol.kg^-1.d^-1),每日一次,连续3d,复制异丙肾上腺素性心肌损伤大鼠模型。结果:中药复方制剂HXTMT能明显减轻心肌损伤程度,血清CK活性,心肌MDA含量,心肌含水量分别减少14%,25%,2%,与模型组比较有显性差异(P<0.05),结论:HXTMT能稳定细胞膜,减轻心肌水肿程度,阻止脂质过氧化物的形成,提示HXTMT对心肌缺血性损伤有细胞保护作用。 相似文献