全文获取类型
收费全文 | 459920篇 |
免费 | 32552篇 |
国内免费 | 8996篇 |
专业分类
耳鼻咽喉 | 5854篇 |
儿科学 | 9067篇 |
妇产科学 | 11079篇 |
基础医学 | 63141篇 |
口腔科学 | 13294篇 |
临床医学 | 41311篇 |
内科学 | 89890篇 |
皮肤病学 | 9289篇 |
神经病学 | 31638篇 |
特种医学 | 16978篇 |
外国民族医学 | 143篇 |
外科学 | 68444篇 |
综合类 | 24440篇 |
现状与发展 | 31篇 |
一般理论 | 67篇 |
预防医学 | 22219篇 |
眼科学 | 11872篇 |
药学 | 39562篇 |
69篇 | |
中国医学 | 6901篇 |
肿瘤学 | 36179篇 |
出版年
2022年 | 2802篇 |
2021年 | 7098篇 |
2020年 | 5059篇 |
2019年 | 5681篇 |
2018年 | 7539篇 |
2017年 | 6202篇 |
2016年 | 6039篇 |
2015年 | 8018篇 |
2014年 | 10472篇 |
2013年 | 11436篇 |
2012年 | 16113篇 |
2011年 | 17145篇 |
2010年 | 10349篇 |
2009年 | 9020篇 |
2008年 | 13497篇 |
2007年 | 14588篇 |
2006年 | 14493篇 |
2005年 | 13683篇 |
2004年 | 11482篇 |
2003年 | 10985篇 |
2002年 | 10333篇 |
2001年 | 29886篇 |
2000年 | 30650篇 |
1999年 | 25913篇 |
1998年 | 6698篇 |
1997年 | 5747篇 |
1996年 | 5009篇 |
1995年 | 4511篇 |
1994年 | 3969篇 |
1993年 | 3421篇 |
1992年 | 16668篇 |
1991年 | 15332篇 |
1990年 | 14636篇 |
1989年 | 14357篇 |
1988年 | 12907篇 |
1987年 | 12318篇 |
1986年 | 11282篇 |
1985年 | 10463篇 |
1984年 | 6978篇 |
1983年 | 5641篇 |
1982年 | 2743篇 |
1979年 | 5500篇 |
1978年 | 3345篇 |
1977年 | 2963篇 |
1975年 | 2636篇 |
1974年 | 3064篇 |
1973年 | 2863篇 |
1972年 | 2828篇 |
1971年 | 2773篇 |
1969年 | 2543篇 |
排序方式: 共有10000条查询结果,搜索用时 234 毫秒
81.
82.
83.
84.
Parallel enzyme‐linked immunosorbent assay screening for human immunodeficiency virus among blood donors in five Chinese blood centres: a retrospective analysis 下载免费PDF全文
85.
86.
87.
88.
Fei Xu Ming‐Liang Ye Yu‐Peng Zhang Wen‐Jie Li Meng‐Ting Li Hai‐Zhou Wang Xiao Qiu Yan Xu Jin‐Wen Yin Qian Hu Wan‐Hui Wei Ying Chang Lan Liu Qiu Zhao 《Cancer science》2020,111(5):1528-1541
Resistance to chemotherapy is a major challenge for the treatment of patients with colorectal cancer (CRC). Previous studies have found that microRNAs (miRNAs) play key roles in drug resistance; however, the role of miRNA‐373‐3p (miR‐375‐3p) in CRC remains unclear. The current study aimed to explore the potential function of miR‐375‐3p in 5‐fluorouracil (5‐FU) resistance. MicroRNA‐375‐3p was found to be widely downregulated in human CRC cell lines and tissues and to promote the sensitivity of CRC cells to 5‐FU by inducing colon cancer cell apoptosis and cycle arrest and by inhibiting cell growth, migration, and invasion in vitro. Thymidylate synthase (TYMS) was found to be a direct target of miR‐375‐3p, and TYMS knockdown exerted similar effects as miR‐375‐3p overexpression on the CRC cellular response to 5‐FU. Lipid‐coated calcium carbonate nanoparticles (NPs) were designed to cotransport 5‐FU and miR‐375‐3p into cells efficiently and rapidly and to release the drugs in a weakly acidic tumor microenvironment. The therapeutic effect of combined miR‐375 + 5‐FU/NPs was significantly higher than that of the individual treatments in mouse s.c. xenografts derived from HCT116 cells. Our results suggest that restoring miR‐375‐3p levels could be a future novel therapeutic strategy to enhance chemosensitivity to 5‐FU. 相似文献
89.
Harinakshi Sanikini David C. Muller Marisa Sophiea Sabina Rinaldi Antonio Agudo Eric J. Duell Elisabete Weiderpass Kim Overvad Anne Tjønneland Jytte Halkjær Marie-Christine Boutron-Ruault Franck Carbonnel Iris Cervenka Heiner Boeing Rudolf Kaaks Tilman Kühn Antonia Trichopoulou Georgia Martimianaki Anna Karakatsani Valeria Pala Domenico Palli Amalia Mattiello Rosario Tumino Carlotta Sacerdote Guri Skeie Charlotta Rylander María-Dolores Chirlaque López Maria-Jose Sánchez Eva Ardanaz Sara Regnér Tanja Stocks Bas Bueno-de-Mesquita Roel C.H. Vermeulen Dagfinn Aune Tammy Y.N. Tong Nathalie Kliemann Neil Murphy Marc Chadeau-Hyam Marc J. Gunter Amanda J. Cross 《International journal of cancer. Journal international du cancer》2020,146(4):929-942
Obesity has been associated with upper gastrointestinal cancers; however, there are limited prospective data on associations by subtype/subsite. Obesity can impact hormonal factors, which have been hypothesized to play a role in these cancers. We investigated anthropometric and reproductive factors in relation to esophageal and gastric cancer by subtype and subsite for 476,160 participants from the European Prospective Investigation into Cancer and Nutrition cohort. Multivariable hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox models. During a mean follow-up of 14 years, 220 esophageal adenocarcinomas (EA), 195 esophageal squamous cell carcinomas, 243 gastric cardia (GC) and 373 gastric noncardia (GNC) cancers were diagnosed. Body mass index (BMI) was associated with EA in men (BMI ≥30 vs. 18.5–25 kg/m2: HR = 1.94, 95% CI: 1.25–3.03) and women (HR = 2.66, 95% CI: 1.15–6.19); however, adjustment for waist-to-hip ratio (WHR) attenuated these associations. After mutual adjustment for BMI and HC, respectively, WHR and waist circumference (WC) were associated with EA in men (HR = 3.47, 95% CI: 1.99–6.06 for WHR >0.96 vs. <0.91; HR = 2.67, 95% CI: 1.52–4.72 for WC >98 vs. <90 cm) and women (HR = 4.40, 95% CI: 1.35–14.33 for WHR >0.82 vs. <0.76; HR = 5.67, 95% CI: 1.76–18.26 for WC >84 vs. <74 cm). WHR was also positively associated with GC in women, and WC was positively associated with GC in men. Inverse associations were observed between parity and EA (HR = 0.38, 95% CI: 0.14–0.99; >2 vs. 0) and age at first pregnancy and GNC (HR = 0.54, 95% CI: 0.32–0.91; >26 vs. <22 years); whereas bilateral ovariectomy was positively associated with GNC (HR = 1.87, 95% CI: 1.04–3.36). These findings support a role for hormonal pathways in upper gastrointestinal cancers. 相似文献
90.
目的 初步探讨应用艾尔巴韦/格拉瑞韦治疗慢性丙型肝炎(CHC)患者的疗效。方法 2017年3月~2018年3月仙桃市第一人民医院感染病科收治的CHC患者82例,被随机分为对照组41例和观察组41例,分别给予聚乙二醇干扰素-α联合利巴韦林治疗和艾尔巴韦/格拉瑞韦治疗,两组均连续治疗24周。采用RT- PCR法检测血清 HCV RNA,采用全基因序列测定法行病毒基因分型。比较两组早期病毒学应答(EVR)、治疗结束时病毒学应答(ETVR)和持续病毒学应答(SVR)。结果 在治疗结束时,观察组血清丙氨酸氨基转移酶(ALT)水平为(47.9±19.7)U/L,显著低于对照组【(63.5±21.2)U/L,P<0.05】,天冬氨酸氨基转移酶(AST)水平为(55.5±22.3)U/L,显著低于对照组【(81.3±25.8)U/L,P<0.05】;观察组EVR、ETVR和SVR分别为48.8%、63.4%和70.7%,与对照组的41.5%、53.7%和65.8%比,无统计学差异(P>0.05);18例观察组非HCV Ⅰ型感染者EVR、ETVR和SVR分别为88.9%、94.4%和88.9%,显著高于同组23例HCV Ⅰ型感染者(分别为52.2%、60.9%和52.2%, P<0.05),而与对照组15例非HCV Ⅰ型感染者比,无统计学差异(分别为86.7%、93.3%和73.3%, P>0.05);观察组SVR12为87.8%(36/41),显著高于对照组的73.2%(30/41,P<0.05)。结论 应用直接抗病毒(DAA)药物艾尔巴韦/格拉瑞韦治疗CHC患者近期疗效达到,但远期疗效似优于标准治疗方案, 值得临床进一步验证。 相似文献