全文获取类型
收费全文 | 12245篇 |
免费 | 951篇 |
国内免费 | 570篇 |
专业分类
耳鼻咽喉 | 88篇 |
儿科学 | 117篇 |
妇产科学 | 139篇 |
基础医学 | 1881篇 |
口腔科学 | 322篇 |
临床医学 | 713篇 |
内科学 | 1769篇 |
皮肤病学 | 148篇 |
神经病学 | 1015篇 |
特种医学 | 350篇 |
外国民族医学 | 6篇 |
外科学 | 670篇 |
综合类 | 1809篇 |
现状与发展 | 4篇 |
预防医学 | 553篇 |
眼科学 | 314篇 |
药学 | 2219篇 |
6篇 | |
中国医学 | 631篇 |
肿瘤学 | 1012篇 |
出版年
2024年 | 30篇 |
2023年 | 144篇 |
2022年 | 268篇 |
2021年 | 380篇 |
2020年 | 342篇 |
2019年 | 342篇 |
2018年 | 327篇 |
2017年 | 338篇 |
2016年 | 358篇 |
2015年 | 420篇 |
2014年 | 706篇 |
2013年 | 872篇 |
2012年 | 762篇 |
2011年 | 849篇 |
2010年 | 635篇 |
2009年 | 659篇 |
2008年 | 714篇 |
2007年 | 663篇 |
2006年 | 588篇 |
2005年 | 571篇 |
2004年 | 481篇 |
2003年 | 452篇 |
2002年 | 397篇 |
2001年 | 332篇 |
2000年 | 258篇 |
1999年 | 254篇 |
1998年 | 243篇 |
1997年 | 176篇 |
1996年 | 170篇 |
1995年 | 133篇 |
1994年 | 107篇 |
1993年 | 113篇 |
1992年 | 89篇 |
1991年 | 66篇 |
1990年 | 61篇 |
1989年 | 52篇 |
1988年 | 45篇 |
1987年 | 42篇 |
1986年 | 35篇 |
1985年 | 51篇 |
1984年 | 52篇 |
1983年 | 37篇 |
1982年 | 34篇 |
1981年 | 26篇 |
1980年 | 24篇 |
1979年 | 25篇 |
1978年 | 12篇 |
1977年 | 12篇 |
1976年 | 10篇 |
1973年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Osric A. Forrest Daniel M. Chopyk Yael Gernez Milton R. Brown Carol K. Conrad Richard B. Moss Vin Tangpricha Limin Peng Rabindra Tirouvanziam 《Journal of cystic fibrosis》2019,18(1):64-70
Background
Resistin is an immunometabolic mediator that is elevated in several inflammatory disorders. A ligand for Toll-like receptor 4, resistin modulates the recruitment and activation of myeloid cells, notably neutrophils. Neutrophils are major drivers of cystic fibrosis (CF) lung disease, in part due to the release of human neutrophil elastase- and myeloperoxidase-rich primary granules, leading to tissue damage. Here we assessed the relationship of resistin to CF lung disease.Methods
Resistin levels were measured in plasma and sputum from three retrospective CF cohorts spanning a wide range of disease. We also assessed the ability of neutrophils to secrete resistin upon activation in vitro. Finally, we constructed a multivariate model assessing the relationship between resistin levels and lung function.Results
Plasma resistin levels were only marginally higher in CF than in healthy control subjects. By contrast, sputum resistin levels were very high in CF, reaching 50–100 fold higher levels than in plasma. Among CF patients, higher plasma resistin levels were associated with allergic bronchopulmonary aspergillosis, and higher sputum resistin levels were associated with CF-related diabetes. Mechanistically, in vitro release of neutrophil primary granules was concomitant with resistin secretion. Overall, sputum resistin levels were negatively correlated with CF lung function, independently of other variables (age, sex, and genotype).Conclusions
Our data establish relationships between resistin levels in the plasma and sputum of CF patients that correlate with disease status, and identify resistin as a novel mechanistic link between neutrophilic inflammation and lung disease in CF. 相似文献2.
《Drug discovery today》2022,27(6):1733-1742
Compounds that exhibit assay interference or undesirable mechanisms of bioactivity are routinely encountered in assays at various stages of drug discovery. We observed that assays for the investigation of thiol-reactive and redox-active compounds have not been collected in a comprehensive review. Here, we review these assays and subject them to experimental optimization to improve their reliability. We demonstrate the usefulness of our assay cascade by assaying a library of bioactive compounds, chemical probes, and a set of approved drugs. These high-throughput assays should complement the array of wet-lab and in silico assays during the initial stages of hit discovery campaigns to pursue only hit compounds with tractable mechanisms of action. 相似文献
3.
Marie V. Plaisime PhD MPH Marie Jipguep-Akhtar PhD Joseph J. Locascio PhD Harolyn M. E. Belcher MD MHS Rachel R. Hardeman PhD MPH Katherine Picho-Kiroga PhD Sylvia P. Perry PhD Sean M. Phelan PhD MPH Michelle van Ryn PhD LMFT MPH John F. Dovidio PhD 《Health services research》2023,58(Z2):229-237
Objective
To examine the experience of interracial anxiety among health professionals and how it may affect the quality of their interactions with patients from racially marginalized populations. We explored the influence of prior interracial exposure—specifically through childhood neighborhoods, college student bodies, and friend groups—on interracial anxiety among medical students and residents. We also examined whether levels of interracial anxiety change from medical school through residency.Data Source
Web-based longitudinal survey data from the Medical Student Cognitive Habits and Growth Evaluation Study.Study Design
We used a retrospective longitudinal design with four observations for each trainee. The study population consisted of non-Black US medical trainees surveyed in their 1st and 4th years of medical school and 2nd and 3rd years of residency. Mixed effects longitudinal models were used to assess predictors of interracial anxiety and assess changes in interracial anxiety scores over time.Principal Findings
In total, 3155 non-Black medical trainees were followed for 7 years. Seventy-eight percent grew up in predominantly White neighborhoods. Living in predominantly White neighborhoods and having less racially diverse friends were associated with higher levels of interracial anxiety among medical trainees. Trainees' interracial anxiety scores did not substantially change over time; interracial anxiety was highest in the 1st year of medical school, lowest in the 4th year, and increased slightly during residency.Conclusions
Neighborhood and friend group composition had independent effects on interracial anxiety, indicating that premedical racial socialization may affect medical trainees' preparedness to interact effectively with diverse patient populations. Additionally, the lack of substantial change in interracial anxiety throughout medical training suggests the importance of providing curricular tools and structure (e.g., instituting interracial cooperative learning activities) to foster the development of healthy interracial relationships. 相似文献4.
5.
目的:通过检测人绒癌细胞株Be Wo合体化过程中增殖细胞核抗原(proliferating cell nuclear antigen,PCNA)、生存素(Survivin)蛋白表达的变化,探讨滋养细胞合体化后增殖性的变化,为恶性滋养细胞肿瘤,尤其是耐药恶性滋养细胞肿瘤的临床治疗提供新的思路和方法。方法:利用毛喉素(forskolin)诱导Be Wo细胞株融合;应用逆转录聚合酶链反应(RT-PCR)检测促融素(Syncytin)在forskolin作用不同时间的Be Wo细胞株中的表达;应用蛋白质印迹(Western blotting)检测PCNA、Survivin蛋白在forskolin作用不同时间的Be Wo细胞株中的表达;应用噻唑蓝比色分析实验(MTT)法检测forskolin作用不同时间的绒癌细胞株Be Wo的增殖能力。结果:1forskolin作用后的Be Wo细胞株Syncytin基因的表达增强,且随着forskolin作用时间的延长,Syncytin的表达更强,于48 h达到高峰。2forskolin作用后的Be Wo细胞株PCNA、Survivin蛋白的表达降低。3forskolin作用后的Be Wo细胞株的增殖能力下降,且不同作用时间的差异有统计学意义;forskolin作用的时间越长,Be Wo细胞株增殖能力下降越明显。结论:人绒癌细胞株Be Wo合体化后PCNA、Survivin蛋白的表达降低,说明人绒癌细胞株Be Wo合体化后增殖性降低,推测诱导滋养细胞合体化可能对临床治疗恶性滋养细胞肿瘤具有一定作用。 相似文献
6.
7.
目的 通过与LBL教学法对比,探讨PBL教学法在核医学科课间实习教学中的应用效果.方法 选取哈尔滨医科大学2016级临床医学专业本科二班学生72人,随机分为实验组和对照组,每组各36人,在课间实习教学中分别实施PBL教学法和LBL教学法.实习结束后,通过考试及问卷调查,进行教学法评价.结果 观察组在考试成绩、学习兴趣、学习热情、教学满意度、培养临床思维、增强知识点掌握等教学法评价指标均优于对照组,具有统计学意义(P<0.05).结论 与LBL教学法相比,PBL教学法应用于核医学科课间实习教学中更能激发学生学习兴趣、增强综合素质,从而提高教学效果. 相似文献
8.
9.
Metabolic abnormalities of gastrointestinal mucosa in celiac disease: An in vitro proton nuclear magnetic resonance spectroscopy study 下载免费PDF全文
10.
从包涵体中纯化重组人幽门螺杆菌热休克蛋白A亚单位 总被引:3,自引:1,他引:2
目的:建立一种有效从包涵体中纯化重组人幽门螺杆菌热休克蛋白A亚单位HspA的方法。方法:重组基因工程大肠杆菌发酵后,表达的Hp r HspA包涵体经洗涤,变性,复性,采用Q Sepharose High Performance阴离子交换层析和Superdex75凝胶过滤层析分离纯化,使用SDS-PAGE和HPLC检测纯度,选用ELISA和动物实验对纯化蛋白的免疫学活性和生物学活性进行鉴定。结果:Hp的HspA包涵经洗涤和溶解后,Hp的HspA的纯度>60%,包涵体溶解液经阴离子交换层析和凝胶过滤层析后纯度超过95%,Hp的HspA纯品经检测具有良好的免疫学活性和生物学活性。结论:本研究建立的分离纯化方法可从包涵体中获得高纯度的重组HspA蛋白,为进一步的动物实验研究奠定了基础。 相似文献