全文获取类型
收费全文 | 152255篇 |
免费 | 36042篇 |
国内免费 | 5427篇 |
专业分类
耳鼻咽喉 | 2720篇 |
儿科学 | 3230篇 |
妇产科学 | 2880篇 |
基础医学 | 8892篇 |
口腔科学 | 6156篇 |
临床医学 | 33322篇 |
内科学 | 32152篇 |
皮肤病学 | 3796篇 |
神经病学 | 14446篇 |
特种医学 | 5445篇 |
外国民族医学 | 41篇 |
外科学 | 23259篇 |
综合类 | 11235篇 |
现状与发展 | 55篇 |
一般理论 | 5篇 |
预防医学 | 17480篇 |
眼科学 | 3525篇 |
药学 | 7399篇 |
67篇 | |
中国医学 | 4307篇 |
肿瘤学 | 13312篇 |
出版年
2024年 | 1056篇 |
2023年 | 6217篇 |
2022年 | 4079篇 |
2021年 | 6340篇 |
2020年 | 8017篇 |
2019年 | 4101篇 |
2018年 | 8949篇 |
2017年 | 9325篇 |
2016年 | 9657篇 |
2015年 | 10622篇 |
2014年 | 13646篇 |
2013年 | 14906篇 |
2012年 | 7801篇 |
2011年 | 7920篇 |
2010年 | 9618篇 |
2009年 | 11337篇 |
2008年 | 6015篇 |
2007年 | 5147篇 |
2006年 | 6035篇 |
2005年 | 4407篇 |
2004年 | 3241篇 |
2003年 | 3076篇 |
2002年 | 2766篇 |
2001年 | 3331篇 |
2000年 | 2370篇 |
1999年 | 2855篇 |
1998年 | 2763篇 |
1997年 | 2644篇 |
1996年 | 2504篇 |
1995年 | 2205篇 |
1994年 | 1547篇 |
1993年 | 1162篇 |
1992年 | 1117篇 |
1991年 | 963篇 |
1990年 | 807篇 |
1989年 | 759篇 |
1988年 | 701篇 |
1987年 | 554篇 |
1986年 | 510篇 |
1985年 | 412篇 |
1984年 | 341篇 |
1983年 | 345篇 |
1982年 | 255篇 |
1981年 | 221篇 |
1980年 | 133篇 |
1979年 | 91篇 |
1978年 | 129篇 |
1977年 | 130篇 |
1976年 | 92篇 |
1974年 | 89篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Objective
The aim of the study was to estimate the effect of the state-based reinsurance programs through the section 1332 State Innovation Waivers on health insurance marketplace premiums and insurer participation.Data Source
2015 to 2022 Robert Wood Johnson Foundation Health Insurance Exchange Compare Datasets.Study Design
An event study difference-in-differences (DD) model separately for each year of implementation and a synthetic control method (SCM) are used to estimate year-by-year effects following program implementation.Data Collection/Extraction Methods
Not applicable.Principal Findings
Reinsurance programs were associated with a decline in premiums in the first year of implementation by 10%–13%, 5%–19%, and 11%–17% for bronze, silver, and gold plans (p < 0.05). There is a trend of sustained declines especially for states that implemented their programs in 2019 and 2020. The SCM analyses suggest some effect heterogeneity across states but also premium declines across most states. There is no evidence that reinsurance programs affected insurer participation.Conclusion
State-based reinsurance programs have the potential to improve the affordability of health insurance coverage. However, reinsurance programs do not appear to have had an effect on insurer participation, highlighting the need for policy makers to consider complementary strategies to encourage insurer participation. 相似文献2.
3.
4.
5.
6.
7.
8.
9.
Zongzhang Huang Qigu Yao Jianping Zhu Ying He Yanghao Chen Feng Wu Teng Hua 《Diagnostic and interventional imaging》2021,102(5):279-285
PurposeThe purpose of this study was to make a systematic review and meta-analysis to determine the stent diameter (8 mm vs. 10 mm) that conveys better safety and clinical efficacy for transjugular intrahepatic portosystemic shunt (TIPS).Materials and methodsFour databases were used to identify clinical trials published from inception until March 2020. Data were extracted to estimate and compare one-year and three-year overall survivals, hepatic encephalopathy, variceal rebleeding, and shunt dysfunction rates between patients with 8 mm covered stents and those with 10 mm covered stents.ResultsFive eligible studies were selected, which included 489 patients (316 men, 173 women). The 8 mm covered stent group had higher efficacy regarding one-year or three-year overall survival (odds ratio [OR], 2.88; P = 0.003) and (OR, 1.81; P = 0.04) and lower hepatic encephalopathy (OR, 0.69; P = 0.04) compared with 10 mm covered stent group. There were no significant differences in variceal rebleeding rate (OR 0.80; P = 0.67). However, shunt dysfunction was lower in 10 mm covered stent group (OR, 2.26; P = 0.003).ConclusionsOur results suggest that the use of 8 mm covered stents should be preferred to that of 10 mm covered stents for TIPS placement when portal pressure is frequently monitored. 相似文献
10.
目的探讨C型凝集素受体Dectin-2在烟曲霉菌感染中的作用及机制。方法用紫外线灭活的烟曲霉菌膨胀态分生孢子刺激野生型(wild type, WT)和Dectin-2缺失(Clec4n-/-)小鼠骨髓来源的巨噬细胞(bone marrow derived macrophages, BMDMs)。刺激20min及40min后,利用Western印迹法检测BMDMs中脾酪氨酸激酶(spleen tyrosine kinase, Syk)和核转录因子κB抑制因子(inhibitor-κB, IκBα)的磷酸化水平。刺激16h后,利用酶联免疫吸附法(enzyme-linked immunosorbent assay, ELISA)检测BMDMs细胞上清液中IL-6、TNF-α和IL-12p40的水平。另一方面,利用压舌感染的方法在WT和Clec4n-/-小鼠中构建烟曲霉菌肺部感染模型。感染2d后,统计小鼠整个肺脏荷菌量,并检测肺脏匀浆液中IL-6和IL-12p40水平。结果体外试验提示,烟曲霉菌刺激后,Dectin-2缺失的BMDMs中Syk和IκBα的磷酸化水平及IL-6、TNF-α和IL-12p40水平显著下降(P<0.05)。体内试验发现,烟曲霉菌感染后,Dectin-2缺失小鼠中肺脏荷菌量显著升高(P<0.05),肺脏匀浆液内IL-6、IL-12p40水平显著降低(P<0.05)。结论C型凝集素受体Dectin-2激活烟曲霉菌诱导的NF-κB信号通路并介导促炎细胞因子的产生,可在小鼠肺烟曲霉菌病动物模型中发挥保护性作用。 相似文献