全文获取类型
收费全文 | 14601篇 |
免费 | 1341篇 |
国内免费 | 1109篇 |
专业分类
耳鼻咽喉 | 123篇 |
儿科学 | 156篇 |
妇产科学 | 162篇 |
基础医学 | 1688篇 |
口腔科学 | 189篇 |
临床医学 | 1926篇 |
内科学 | 2062篇 |
皮肤病学 | 106篇 |
神经病学 | 778篇 |
特种医学 | 462篇 |
外国民族医学 | 10篇 |
外科学 | 1510篇 |
综合类 | 3017篇 |
现状与发展 | 6篇 |
一般理论 | 1篇 |
预防医学 | 885篇 |
眼科学 | 327篇 |
药学 | 1628篇 |
15篇 | |
中国医学 | 878篇 |
肿瘤学 | 1122篇 |
出版年
2024年 | 46篇 |
2023年 | 242篇 |
2022年 | 551篇 |
2021年 | 792篇 |
2020年 | 609篇 |
2019年 | 469篇 |
2018年 | 462篇 |
2017年 | 436篇 |
2016年 | 457篇 |
2015年 | 657篇 |
2014年 | 827篇 |
2013年 | 735篇 |
2012年 | 1115篇 |
2011年 | 1207篇 |
2010年 | 851篇 |
2009年 | 667篇 |
2008年 | 800篇 |
2007年 | 824篇 |
2006年 | 801篇 |
2005年 | 767篇 |
2004年 | 487篇 |
2003年 | 450篇 |
2002年 | 395篇 |
2001年 | 385篇 |
2000年 | 318篇 |
1999年 | 339篇 |
1998年 | 198篇 |
1997年 | 210篇 |
1996年 | 165篇 |
1995年 | 135篇 |
1994年 | 111篇 |
1993年 | 66篇 |
1992年 | 86篇 |
1991年 | 77篇 |
1990年 | 74篇 |
1989年 | 65篇 |
1988年 | 42篇 |
1987年 | 38篇 |
1986年 | 44篇 |
1985年 | 20篇 |
1984年 | 11篇 |
1983年 | 7篇 |
1982年 | 6篇 |
1981年 | 2篇 |
1979年 | 5篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
51.
苯并二氢吡喃腙衍生物的合成及其初步药理活性 总被引:4,自引:0,他引:4
为进一步筛选活性更强、副作用更小的抗绝经后骨质疏松症药物 ,在综合考察雷洛昔芬和异丙氧基异黄酮的基础上 ,设计合成一系列苯并二氢吡喃腙化合物 .化合物的结构均经波谱鉴定 ,并通过研究其对幼年小鼠子宫增重和血碱性磷酸酶活性的影响 ,初步考察化合物的药理活性 .结果表明 ,XY990 2具有较弱的雌激素受体激动作用和一定的雌激素受体拮抗作用 ,并有助于成骨细胞增殖 ,对治疗骨质疏松症是有利的 . 相似文献
52.
目的:观察青芪散对免疫损伤小鼠淋巴细胞亚群和自然杀伤细胞(NK细胞)的影响.方法:采用青芪散小、中、大3种剂量治疗免疫性肝损伤小鼠,与迈普新治疗对照,观察其对淋巴细胞亚群、NK细胞及肝脏病理的影响.结果:青芪散中剂量组显著降低CD8 ,提高CD3 、CD4 及CD4 /CD8 比值,与对照组比较差异有统计学意义(P<0.05);实验各组能提高NK细胞活性,其中中剂量组疗效与对肝组织病理学影响一样,较对照组稍优,但无统计意义(P>0.05).结论:青芪散对免疫损伤小鼠特异与非特异性免疫机制有积极作用. 相似文献
53.
为研究Nogo-A基因沉默对细胞凋亡的影响,本文构建了靶向Nogo-A的短发夹样RNA(short hairpin RNA,shRNA)真核表达载体并经脂质体转染到培养的PC12细胞。分别以逆转录聚合酶链反应(RT-PCR)和免疫印迹法检测转染48h后Nogo-A mRNA及蛋白表达的变化。在转染后不同时间应用四甲基偶氮唑盐(MTT)法检测细胞增殖活性,用原位末端标记(TUNEL)法及流式细胞仪检测细胞凋亡率。结果显示:由shRNA产生的小干扰RNA(siRNA)可有效抑制PC12细胞Nogo-A基因的表达。Nogo-A siRNA处理组细胞的增殖活性增加、凋亡率明显下降。本结果提示,Nogo-A基因可能与细胞凋亡有关。 相似文献
54.
Guangshuo Li Shang Wang Yunyun Xiong Hongqiu Gu Kaixuan Yang Xin Yang Chunjuan Wang Chuanying Wang Zixiao Li Xingquan Zhao 《CNS Neuroscience & Therapeutics》2022,28(8):1240
IntroductionThe relationship between statins and intracerebral hemorrhage outcomes is unclear.AimWe aimed to compare the in‐hospital mortality and evacuation of intracranial hematoma rates in patients with primary intracerebral hemorrhage between prior statin users and nonusers.ResultsThe final study population included 66,263 patients. Multivariable logistics analyses showed that prior statin use was not associated with in‐hospital mortality for primary intracerebral hemorrhage (adjusted odd ratio 0.78, 95% CI 0.61–1.01), but reduced the proportion of patients undergoing evacuation of intracranial hematoma (adjusted odd ratio 0.70, 95% CI 0.61–0.82). Propensity score matching analyses yielded similar results.ConclusionPrior statin use was not associated with in‐hospital mortality but did reduce evacuation of intracranial hematoma rates. 相似文献
55.
Rationale:To report a rare case of calculating the IOL power in a cataract patient who underwent both radial keratotomy (RK) and photorefractive keratectomy (PRK).Patient concerns:A 48-year-old woman underwent bilateral RK at age 22 and bilateral PRK at age 46. She developed bilateral corneal haze and corneal endothelial inflammation and received steroids therapy for long time after PRK. Then she was referred to our hospital due to decreased vision in the both eyes.Diagnoses:The patient was diagnosed with binocular complicated cataract, corneal haze, high myopia and post corneal refractive surgery (RK and PRK).Interventions:The patient underwent bilateral phacoemulsification. The IOL power was calculated using SRK/T formula for RK and Haigis-L formula for PRK, respectively. We finally selected the Haigis-L formula and the intraocular lens (SN60WF) was implanted within the capsular bag.Outcomes:After the surgery, both eyes showed myopia drift, and the right eye continuously fluctuated in refractive results. However, by nearly 1 year later, refractive results in both eyes had stabilized, and no other complications had occurred.Lessons:IOL power in patients who undergo both RK and PRK can be reliably calculated using the Shammas-PL, Average of multiple formulas, or Barret True-K No History formulas. Haigis-L formula is not suitable. Such patients require at least three months after surgery to attain refractive stability in both eyes. 相似文献
56.
少见部位骨巨细胞瘤的临床及影像学表现分析 总被引:1,自引:1,他引:0
目的:提高对少见部位骨巨细胞瘤影像学表现的认识能力,降低误诊率。方法:回顾性分析13例经手术病理证实的少见部位骨巨细胞瘤的临床及影像学资料。本组病例均是在拍摄X线正侧位片时首先发现病灶。10例行CT扫描。结果:X线检查诊断为骨巨细胞瘤2例,骨囊肿6例,跟骨结核1例,椎体结核2例,椎体血管瘤1例,椎体骨髓瘤1例。CT扫描检查诊断为骨巨细胞瘤5例,骨囊肿4例,椎体结核1例。13例中Ⅰ级者9例,Ⅱ级者3例,Ⅲ级者1例。结论:少见部位的骨巨细胞瘤影像学特征不典型,易与骨囊肿、骨结核、单发性骨髓瘤相混淆。对特殊部位的骨质膨胀性破坏,皮质变薄,并见有细小骨嵴者应考虑本病。 相似文献
57.
Chengwei Xiang Zekun Yang Ting Xiong Ting Wang Jie Yang Mei Huang Dingxiang Liu Ruiai Chen 《Viruses》2022,14(7)
Avian interferon regulatory factors 1 and 7 (IRF1 and IRF7) play important roles in the host’s innate immunity against viral infection. Our previous study revealed that duck tembusu virus (DTMUV) infection of chicken fibroblasts (DF1) and duck embryo fibroblasts (DEFs) induced the expression of a variety of IFN-stimulated genes (ISGs), including VIPERIN, IFIT5, CMPK2, IRF1, and IRF7. IRF1 was further shown to play a significant role in regulating the up-expression of VIPERIN, IFIT5, and CMPK2 and inhibiting DTMUV replication. In this study, we confirm, through overexpression and knockout approaches, that both IRF1 and IRF7 inhibit DTMUV replication, mainly via regulation of type I IFN expression, as well as the induction of IRF1, VIPERIN, IFIT5, CMPK2, and MX1. In addition, IRF1 directly promoted the expression of VIPERIN and CMPK2 in an IFN-independent manner when IRF7 and type I IFN signaling were undermined. We also found that non-structural protein 2B (NS2B) of DTMUV was able to inhibit the induction of IFN-β mRNA triggered by Newcastle disease virus (NDV) infection or poly(I:C) treatment, revealing a strategy employed by DTMUV to evade host’s immunosurveillance. This study demonstrates that avian IRF7 and IRF1 play distinct roles in the regulation of type I IFN response during DTMUV infection. 相似文献
58.
Rui Zhang Jin Chen Yanqin Xiong Lihong Wang Xinmei Huang Tiange Sun Bingbing Zha Yueyue Wu Cuili Yan Shufei Zang Qin Zhou Zhe Huang Jun Liu 《Journal of Diabetes》2022,14(7):442
BackgroundThis study aims to investigate the potential association of peripheral inflammatory blood cell parameters with the incidence and progression of chronic kidney disease (CKD) in patients with diabetes.MethodsThe cross‐sectional study included 1192 subjects with diabetes derived from one center. The cohort study included 2060 subjects with diabetes derived from another two centers followed up for 4 years. Logistic regression and Cox proportional hazards models were used to evaluate the association of peripheral inflammatory blood cell with CKD.ResultsIn the cross‐sectional study, neutrophil count performed best as an independent risk factor for CKD (odds ratio 2.556 [95% confidence interval 1.111, 5.879]) even after 1:1 case–control matching for age, gender, history of high blood pressure and duration of diabetes. Spline regression revealed a significant linear association of CKD incidence with continuous neutrophil count in excess of 3.6 × 109/L. In the cohort study, subjects were grouped based on tertile of neutrophil count and neutrophil‐to‐lymphocyte ratio. Cox regression analysis results showed that only neutrophil count was independently associated with CKD progression (the highest group vs. the lowest group, hazard ratio 2.293 [95% confidence interval 1.260, 4.171]) after fully adjusting for potential confounders. The cumulative incidence of CKD progression in patients with diabetes gradually increased with increasing neutrophil count (53 (7.7%) subjects in the lowest group vs. 60 (8.2%) in the middle group vs. 78 (12.2%) in the highest group).ConclusionsThis study suggested that neutrophil count is an independent risk factor for progression of CKD in patients with diabetes. 相似文献
59.
60.
目的 分析胰岛素对急性缺血性脑卒中合并糖尿病患者神经功能产生的影响效果。方法 将2016年10月至2017年10月我院接诊的急性缺血性脑卒中合并糖尿病患者中抽取84例纳入研究,常规组采用常规方法治疗,联合组采用常规西医联合胰岛素进行治疗。评价两组患者不同治疗后临床疗效、神经功能改善情况的差异性。结果 治疗后,联合组临床治疗有效率为92.86%,明显高于常规组(P<0.05);联合组神经功能缺损NIHSS评分(5.34±0.11)分,明显低于常规组(P<0.05)。结论 胰岛素对急性缺血性脑卒中合并糖尿病患者神经功能产生的影响效果显著,可推广应用。 相似文献