全文获取类型
收费全文 | 30287篇 |
免费 | 2182篇 |
国内免费 | 1216篇 |
专业分类
耳鼻咽喉 | 165篇 |
儿科学 | 671篇 |
妇产科学 | 241篇 |
基础医学 | 2439篇 |
口腔科学 | 358篇 |
临床医学 | 2943篇 |
内科学 | 3458篇 |
皮肤病学 | 321篇 |
神经病学 | 1354篇 |
特种医学 | 1438篇 |
外国民族医学 | 8篇 |
外科学 | 2393篇 |
综合类 | 3614篇 |
现状与发展 | 4篇 |
预防医学 | 2038篇 |
眼科学 | 506篇 |
药学 | 7626篇 |
6篇 | |
中国医学 | 1938篇 |
肿瘤学 | 2164篇 |
出版年
2024年 | 33篇 |
2023年 | 370篇 |
2022年 | 576篇 |
2021年 | 985篇 |
2020年 | 894篇 |
2019年 | 885篇 |
2018年 | 946篇 |
2017年 | 987篇 |
2016年 | 1043篇 |
2015年 | 1022篇 |
2014年 | 1872篇 |
2013年 | 2535篇 |
2012年 | 1864篇 |
2011年 | 2066篇 |
2010年 | 1608篇 |
2009年 | 1576篇 |
2008年 | 1633篇 |
2007年 | 1525篇 |
2006年 | 1294篇 |
2005年 | 1182篇 |
2004年 | 998篇 |
2003年 | 902篇 |
2002年 | 763篇 |
2001年 | 590篇 |
2000年 | 523篇 |
1999年 | 475篇 |
1998年 | 434篇 |
1997年 | 434篇 |
1996年 | 383篇 |
1995年 | 391篇 |
1994年 | 338篇 |
1993年 | 320篇 |
1992年 | 250篇 |
1991年 | 221篇 |
1990年 | 187篇 |
1989年 | 164篇 |
1988年 | 196篇 |
1987年 | 126篇 |
1986年 | 109篇 |
1985年 | 171篇 |
1984年 | 147篇 |
1983年 | 111篇 |
1982年 | 114篇 |
1981年 | 86篇 |
1980年 | 84篇 |
1979年 | 54篇 |
1978年 | 58篇 |
1977年 | 34篇 |
1976年 | 41篇 |
1975年 | 24篇 |
排序方式: 共有10000条查询结果,搜索用时 375 毫秒
1.
目的:探讨脑出血对酵母沉默信息调节因子2(Sirt2)和炎症的影响。方法:将胶原酶Ⅳ注入SD大鼠右侧
纹状体中建立脑出血模型,通过免疫印迹和ELISA 等方法测定大鼠脑出血后48 h 的Sirt2 的表达及炎症变化。利
用Hemin 诱导PC12 细胞损伤模拟体外脑出血模型,并检测Sirt2 及炎症变化;采用短发夹RNA(shRNA)-Sirt2 沉
默Sirt2 在PC12 细胞中的表达及对炎症的影响。结果:手术后48 h 脑出血行为学评分最低。脑出血组Sirt2 的表达
显著高于假手术组。脑出血组IL-6、IL-1β 表达显著升高。结论:脑出血可以促进Sirt2 的表达和炎症反应,降低
Sirt2 的表达可减缓炎症反应。
关键词 脑出血;沉默信息调节 相似文献
2.
3.
4.
5.
Karen Kayser Ariel Washington Lesley M. Harris Barbara Head 《Journal of psychosocial oncology》2021,39(1):17-34
Abstract
Purpose
Financial hardship can be a major cause of distress among persons with cancer, resulting in chronic stress and impacting physical and emotional health. This paper provides an analysis of the lived experience of cancer patients’ financial hardship from diagnosis to post-treatment. 相似文献6.
《Clinical genitourinary cancer》2022,20(5):442-451
IntroductionSelective internal radiation therapy (SIRT) is a potential treatment of primary renal cell carcinoma (RCC) deemed unsuitable for conventional therapy. RESIRT is the first-in-human study to evaluate safety and feasibility of SIRT for primary RCC.Patients and MethodsPatients with RCC, unsuitable for, or who declined conventional therapy, were eligible. A single transfemoral micro-catheter administration of yttrium-90 (Y-90) resin microspheres (SIR-Spheres) was delivered super selectively via the renal artery to the tumour at intended radiation doses of 75, 100, 150, 200, 300 Gy and a final cohort with a procedural endpoint of “imminent stasis,” in a dose-escalation design. Post-SIRT follow-up was 12 months. Study endpoints included safety and toxicity 30-days and 12-months post-SIRT and tumour response (RECIST v1.1).ResultsIn total, 21 patients were enrolled, mean (SD) age was 75 (9.3) years, WHO performance status was 0 in 81%, 12 (57%) had stage 3 chronic kidney disease, and 7 (33%) had prior contralateral nephrectomy. Overall, 71% of patients completed 12 months of follow-up. Intended doses were delivered without any dose-limiting toxicity. Seventeen out of 21 (81%) patients experienced an adverse event (AE) from any cause within 30 days post-SIRT; all SIRT-related AEs were grade 1 to 2. Best overall tumour responses were partial response 1/21 (4.8%), stable disease 19/21 (90.5%) and progressive disease 1/21 (4.8%).ConclusionThis study demonstrated good tolerability of SIRT at all dose levels including “imminent stasis” in treating primary tumours in RCC patients otherwise unsuitable for conventional therapy. SIRT with Y-90 resin microspheres may be a feasible treatment option for RCC. 相似文献
7.
8.
9.
目的 探究醛糖还原酶和晚期糖基化终末产物受体对糖尿病视网膜病变神经元凋亡的影响。方法 Wistar大鼠36只,随机分为对照组、模型组、转染组,后两组建立糖尿病大鼠模型。模型建立成功后,构建含有晚期糖基化终末产物受体siRNA的质粒并利用慢病毒转染入转染组大鼠体内。造模后4周、8周、12周,记录各组大鼠体质量及空腹血糖。造模后9周,禁食6 h,测定口服葡萄糖耐量。造模后12周,处死全部大鼠后,TUNEL法检测各组大鼠视网膜神经元凋亡情况,荧光分光光度计测定醛糖还原酶活性,Western blotting法测定晚期糖基化终末产物受体的表达,RT-PCR检测视网膜中Bcl-2和Bax mRNA相对表达量。结果 造模后4周、8周、12周,转染组和模型组的大鼠体质量均低于对照组(均为P<0.05);造模后12周,转染组大鼠体质量高于模型组(P<0.05)。造模后4周、8周、12周,各组内大鼠空腹血糖水平均无明显变化(均为P>0.05),转染组和模型组大鼠的空腹血糖水平均高于对照组(均为P<0.05)。模型组和转染组大鼠在口服葡萄糖后30 min时,血糖水平均高于对照组(均为P<0.05);在120 min时分别下降至最低,但仍高于对照组(均为P<0.05)。模型组和转染组的视网膜神经元凋亡指数、醛糖还原酶活性、晚期糖基化终末产物受体和Bax mRNA相对表达量均高于对照组(均为P<0.05),且转染组均高于模型组(均为P<0.05)。模型组和转染组的Bcl-2 mRNA相对表达量均低于对照组(均为P<0.05),转染组低于模型组(P<0.05)。结论 晚期糖基化终末产物结合受体后产生大量的氧自由基损伤,可能是导致糖尿病视网膜神经元凋亡,进而导致糖尿病视网膜病变发生的机制之一。 相似文献
10.
《Respiratory investigation》2022,60(1):137-145
BackgroundSome chronic obstructive pulmonary disease (COPD) patients develop hypoxemia with disease progression, with some even requiring long-term oxygen therapy (LTOT). Lung function, especially diffusing capacity, and the annual decline in PaO2, are reported to be predictive factors of chronic respiratory failure. However, the association between lung morphometry evaluated using computed tomography (CT) images and LTOT initiation is unknown.MethodsWe retrospectively evaluated the relationship between clinical indices, including pulmonary function, body mass index (BMI), and CT parameters, at baseline and LTOT initiation in two prospective COPD cohorts. In the Nara Medical University cohort (n = 76), the low attenuation area (LAA) and its fractal dimension (fractal D) were adapted as the indices for parenchymal destruction in CT images. The association between these CT measurements and LTOT initiation was replicated in the Kyoto University cohort (n = 130).ResultsIn the Nara Medical University cohort, lower BMI (hazard ratio [HR]:0.70, p = 0.006), lower % diffusing capacity (%DLCO) (HR: 0.92, p = 0.006), lower %DLCO/VA (HR, 0.90, p = 0.008), higher RV/TLC (HR, 1.26, p = 0.012), higher LAA% (HR: 1.18, p = 0.001), and lower fractal D (HR: 3.27 × 10?8, p < 0.001) were associated with LTOT initiation. Multivariate analysis in the Kyoto University cohort confirmed that lower %DLCO and lower fractal D were independently associated with LTOT initiation, whereas LAA% was not.ConclusionFractal D, which is the index for morphometric complexity of LAA in CT analysis, is predictive of LTOT initiation in COPD patients. 相似文献