全文获取类型
收费全文 | 1008395篇 |
免费 | 79066篇 |
国内免费 | 23308篇 |
专业分类
耳鼻咽喉 | 12069篇 |
儿科学 | 26482篇 |
妇产科学 | 22418篇 |
基础医学 | 148212篇 |
口腔科学 | 25290篇 |
临床医学 | 105907篇 |
内科学 | 178115篇 |
皮肤病学 | 19104篇 |
神经病学 | 66573篇 |
特种医学 | 37410篇 |
外国民族医学 | 289篇 |
外科学 | 135649篇 |
综合类 | 63896篇 |
现状与发展 | 78篇 |
一般理论 | 179篇 |
预防医学 | 69417篇 |
眼科学 | 25568篇 |
药学 | 85523篇 |
326篇 | |
中国医学 | 19574篇 |
肿瘤学 | 68690篇 |
出版年
2022年 | 8117篇 |
2021年 | 18788篇 |
2020年 | 15201篇 |
2019年 | 16105篇 |
2018年 | 19096篇 |
2017年 | 15882篇 |
2016年 | 16010篇 |
2015年 | 21700篇 |
2014年 | 27792篇 |
2013年 | 30486篇 |
2012年 | 42918篇 |
2011年 | 46958篇 |
2010年 | 28425篇 |
2009年 | 24022篇 |
2008年 | 36704篇 |
2007年 | 38218篇 |
2006年 | 38661篇 |
2005年 | 36951篇 |
2004年 | 30418篇 |
2003年 | 28502篇 |
2002年 | 26668篇 |
2001年 | 43242篇 |
2000年 | 44629篇 |
1999年 | 38811篇 |
1998年 | 12767篇 |
1997年 | 11616篇 |
1996年 | 10776篇 |
1995年 | 10480篇 |
1994年 | 9246篇 |
1993年 | 7637篇 |
1992年 | 25632篇 |
1991年 | 25201篇 |
1990年 | 24318篇 |
1989年 | 23832篇 |
1988年 | 21510篇 |
1987年 | 20641篇 |
1986年 | 19474篇 |
1985年 | 18133篇 |
1984年 | 13158篇 |
1983年 | 11074篇 |
1979年 | 11706篇 |
1978年 | 8194篇 |
1977年 | 6898篇 |
1976年 | 6647篇 |
1975年 | 7318篇 |
1974年 | 8583篇 |
1973年 | 8204篇 |
1972年 | 7724篇 |
1971年 | 7170篇 |
1970年 | 6924篇 |
排序方式: 共有10000条查询结果,搜索用时 203 毫秒
81.
幽门螺杆菌(HP)是革兰阴性微需氧的螺旋样杆菌,主要通过口-口途径在人-人之间感染传播。HP的发现加深了人类对慢性感染、炎症和癌症之间关系的认识。其特定的螺旋形体型、鞭毛及动力、尿素酶和黏附素活性,以及细胞毒素基因A(cagA)、空泡细胞毒素基因A(vacA)等是影响HP感染研究较多的相关致病因素。HP感染在胃癌的发生、发展中可能具有重要作用,但尚未确切证实HP感染是导致胃癌的主因。文章概述了HP感染相关致病因素的研究进展。 相似文献
82.
83.
Juan Carlos Casado-Morente Elena Mora Rivas Carlos O’Connor Reina Soledad Angulo Serrano Estefanía Díaz-Fresno Isabel Sandoval-Menéndez Antonio Becerra M. Jesús Lucio Faustino Núñez-Batalla 《Acta otorrinolaringologica espanola》2021,72(1):21-26
ObjectiveThe aim of this study was to create and validate an abbreviated version of the Spanish Transsexual Voice Questionnaire for Male-to-Female Transsexuals (SvTVQMtF).SettingThe study was conducted by two referral hospitals for voice feminization surgery and by a university department of psychology and speech therapy, all in Spain.Subjects and methodsWe prospectively studied 51 male-to-female transsexuals who underwent voice feminization surgery between January 2017 and December 2018. The SvTVQMtF was completed before and after surgery, and the 10 items with the greatest variation were selected by clinical consensus of an expert panel to develop the short version of the SvTVQMtF (SvTVQMtF-10). The correlation between the total score and the score for each item on the SvTVQMtF and the SvTVQMtF-10 was studied. The internal consistency of the SvTVQMtF-10 was analysed.ResultsGood correlation (Pearson coefficient above .90) was found between the two questionnaires. A significant correlation was found between the total SvTVQMtF-10 score and the score for each item. A significant negative correlation was found between the SvTVQMtF and fundamental frequency after voice feminization surgery. Cronbach's α was .79.ConclusionThe SvTVQMtF-10 is a valid short version of the SvTVQMtF and can be used to quantify voice-related quality of life in MtF transsexuals. 相似文献
84.
Patrick Demkowicz BS Renelle Pointdujour-Lim MD Sofia Miguez BA Yesung Lee BS Bailey S. C. L. Jones BS Christopher A. Barker MD Marcus Bosenberg MD PhD David H. Abramson MD Alexander N. Shoushtari MD Harriet Kluger MD Jasmine H. Francis MD Mario Sznol MD Mathieu F. Bakhoum MD PhD 《Cancer》2023,129(20):3275-3286
85.
Tianshu Liu Yuxian Bai Xiaoyan Lin Wei Li Jufeng Wang Xiaochun Zhang Hongming Pan Chunmei Bai Li Bai Ying Cheng Jingdong Zhang Haijun Zhong Yi Ba Wenwei Hu Ruihua Xu Weijian Guo Shukui Qin Nong Yang Jianwei Lu Kohei Shitara Ming Lei Mingshun Li Nicole Bao Tian Chen Lin Shen 《International journal of cancer. Journal international du cancer》2023,152(4):749-760
First-line chemotherapy for advanced/metastatic human epidermal growth factor receptor 2 (HER2)-negative gastric/gastroesophageal junction cancer (GC/GEJC) has poor median overall survival (OS; <1 year). We report efficacy and safety results from Chinese patients in the phase III global CheckMate 649 study of nivolumab plus chemotherapy vs chemotherapy for the first-line treatment of GC/GEJC/esophageal adenocarcinoma (EAC). Chinese patients with previously untreated advanced or metastatic GC/GEJC/EAC were randomized to receive nivolumab (360 mg Q3W or 240 mg Q2W) plus chemotherapy (XELOX [capecitabine and oxaliplatin] Q3W or FOLFOX [oxaliplatin, leucovorin and 5-fluorouracil] Q2W), nivolumab plus ipilimumab (not reported) or chemotherapy alone. OS, blinded independent central review-assessed progression-free survival (PFS), objective response rate (ORR), duration of response (DOR) and safety are reported. Of 1581 patients enrolled and randomized, 208 were Chinese. In these patients, nivolumab plus chemotherapy resulted in clinically meaningful improvement in median OS (14.3 vs 10.2 months; HR 0.61 [95% CI: 0.44-0.85]), median PFS (8.3 vs 5.6 months; HR 0.57 [95% CI: 0.40-0.80]), ORR (66% vs 45%) and median DOR (12.2 vs 5.6 months) vs chemotherapy, respectively. The safety profile was acceptable, with no new safety signals observed. Consistent with results from the global primary analysis of CheckMate 649, nivolumab plus chemotherapy demonstrated a clinically meaningful improvement in OS and PFS and higher response rate vs chemotherapy and an acceptable safety profile in Chinese patients. Nivolumab plus chemotherapy represents a new standard first-line treatment for Chinese patients with non-HER2-positive advanced GC/GEJC/EAC. 相似文献
86.
目的: 建立首批1,6-脱水衍生物系统适用性对照品,完善国家标准。方法:以欧洲药典依诺肝素钠对照品(EP Enoxaparin Sodium,Batch5)为系统适用性对照品,采用依诺肝素钠新国家标准草案 “1,6-脱水衍生物”检查法,对依诺肝素钠国家对照品(批号:140810-201801)进行1,6-脱水衍生物含量测定,由全国14个药品检验机构及依诺肝素生产企业实验室协作标定。结果:对依诺肝素钠系统适用性国家对照品(批号:140810-201801)1,6-脱水衍生物含量标定结果为20.3%,并对实验室内误差进行考察,14个实验室中有1个实验室(Lab1)标准差(SD)为1.8%,5个实验室(Lab2、Lab4、Lab10、 Lab11和Lab13)的SD为0.5%~0.7%,其余8个实验室的SD值均小于0.5%。对实验室间误差进行考察,有效数据的SD值为0.6%,相对标准偏差(RSD)为3.2%。结论:经国家药品标准物质委员会审定后批准, 依诺肝素系统适用性国家对照品(批号:140810-201801)增加1,6-脱水衍生物含量赋值,可以用于依诺肝素钠1,6-脱水衍生物检查系统适用性考察使用。 相似文献
87.
88.
Manyu Gu Shuyi Wang Wandi Cao Dejian Yan Yi Cao 《Journal of applied toxicology : JAT》2022,42(4):651-659
Recently, we reported that titanium dioxide (TiO2) materials activated endothelial cells via Kruppel-like factor (KLF)-mediated nitric oxide (NO) dysfunction, but the roles of physical properties of materials are not clear. In this study, we prepared nanobelts from P25 particles and compared their adverse effects to human umbilical vein endothelial cells (HUVECs). TiO2 nanobelts had belt-like morphology but comparable surface areas as P25 particles. When applied to HUVECs, P25 particles or nanobelts did not induce cytotoxicity, although nanobelts were much more effective to increase intracellular Ti element concentrations compared the same amounts of P25 particles. Only nanobelts significantly induced THP-1 adhesion onto HUVECs. Consistently, nanobelts were more significant to induce the expression of intracellular adhesion molecule-1 (ICAM1) and the release of soluble ICAM-1 (sICAM-1), indicating that nanobelts were more potent to induce endothelial activation in vitro. As the mechanisms for endothelial activation, both P25 and nanobelts reduced the generation of intracellular NO as well as the expression of NO regulators KLF2 and KLF4. Combined, the results from this study indicated that the different morphologies of P25 particles and nanobelts only changed their internalization into HUVECs but showed minimal impact on KLF-mediated NO signaling pathways. 相似文献
89.
90.