全文获取类型
收费全文 | 5716篇 |
免费 | 473篇 |
国内免费 | 138篇 |
专业分类
耳鼻咽喉 | 67篇 |
儿科学 | 105篇 |
妇产科学 | 121篇 |
基础医学 | 673篇 |
口腔科学 | 143篇 |
临床医学 | 604篇 |
内科学 | 1311篇 |
皮肤病学 | 57篇 |
神经病学 | 357篇 |
特种医学 | 133篇 |
外科学 | 818篇 |
综合类 | 285篇 |
一般理论 | 7篇 |
预防医学 | 368篇 |
眼科学 | 111篇 |
药学 | 481篇 |
1篇 | |
中国医学 | 146篇 |
肿瘤学 | 539篇 |
出版年
2023年 | 39篇 |
2022年 | 78篇 |
2021年 | 156篇 |
2020年 | 96篇 |
2019年 | 134篇 |
2018年 | 146篇 |
2017年 | 113篇 |
2016年 | 155篇 |
2015年 | 190篇 |
2014年 | 240篇 |
2013年 | 274篇 |
2012年 | 399篇 |
2011年 | 440篇 |
2010年 | 281篇 |
2009年 | 249篇 |
2008年 | 350篇 |
2007年 | 386篇 |
2006年 | 305篇 |
2005年 | 339篇 |
2004年 | 302篇 |
2003年 | 276篇 |
2002年 | 241篇 |
2001年 | 194篇 |
2000年 | 162篇 |
1999年 | 108篇 |
1998年 | 44篇 |
1997年 | 45篇 |
1996年 | 35篇 |
1995年 | 28篇 |
1994年 | 27篇 |
1993年 | 19篇 |
1992年 | 50篇 |
1991年 | 61篇 |
1990年 | 50篇 |
1989年 | 33篇 |
1988年 | 26篇 |
1987年 | 16篇 |
1986年 | 30篇 |
1985年 | 28篇 |
1984年 | 19篇 |
1983年 | 18篇 |
1982年 | 8篇 |
1981年 | 8篇 |
1980年 | 13篇 |
1979年 | 18篇 |
1978年 | 20篇 |
1977年 | 11篇 |
1976年 | 9篇 |
1974年 | 11篇 |
1973年 | 8篇 |
排序方式: 共有6327条查询结果,搜索用时 31 毫秒
991.
Pharmaceutical Chemistry Journal - Two black rice pigment components, BR1 and BR2, were obtained by thin layer chromatography. From five experiments for in vitro testing of the scavenging ability,... 相似文献
992.
Robert A. Fargione Natchada Tansuebchueasai Rachel Lee Tak Yee Tania Tai 《Survey of ophthalmology》2019,64(2):217-224
Insertion of glaucoma drainage devices has become a mainstay in the surgical management of multiple forms of glaucoma, and the indications for this procedure continue to expand. A unique clinical challenge in the postoperative care of these devices is the hypertensive phase, a period of postoperative intraocular pressure elevation in the first three months after surgery. We discuss the influence of a variety of factors on the development of the hypertensive phase after glaucoma drainage implantation, including type of device, device material, and device surface area. Furthermore, several intraoperative and postoperative interventions are investigated as attempts to mitigate this phenomenon. Included among these are the use of antimetabolites, collagen matrix, and a variety of approaches to postoperative inflammation and intraocular pressure control. We provide an overview of our current knowledge of the etiology and management of the hypertensive phase. 相似文献
993.
Hsiu‐Ju Yen Shih‐Hsiang Chen Tsung‐Yen Chang Chao‐Ping Yang Dong‐Tsamn Lin Iou‐Jih Hung Kai‐Hsin Lin Jiann‐Shiuh Chen Chih‐Cheng Hsiao Tai‐Tsung Chang Te‐Kao Chang Ching‐Tien Peng Ming‐Tsan Lin Tang‐Her Jaing Hsi‐Che Liu Shiann‐Tarng Jou Meng‐Yao Lu Chao‐Neng Cheng Jiunn‐Ming Sheen Shyh‐Shin Chiou Giun‐Yi Hung Kang‐Hsi Wu Ting‐Chi Yeh Shih‐Chung Wang Rong‐Long Chen Hsiu‐Hao Chang Yung‐Li Yang Shu‐Huey Chen Shin‐Nan Cheng Yu‐Hsiang Chang Bow‐Wen Chen Yuh‐Lin Hsieh Fang‐Liang Huang Wan‐Ling Ho Jinn‐Li Wang Chia‐Yau Chang Yu‐Hua Chao Pei‐Chin Lin Yu‐Chieh Chen Yu‐Mei Liao Tung‐Huei Lin Lee‐Yung Shih Der‐Cherng Liang 《Pediatric blood & cancer》2017,64(10)
994.
Hser Yih-Ing Li Ming D. Grella Christine Brecht Lynn Chen Zhiwei Chang Sulie L. Chang Linda Normand Jacques Tai Betty 《Journal of neuroimmune pharmacology》2017,12(2):79-80
The 2017 CALDAR Summer Institute on Longituidnal Research and International Conference Series to Promote Global Health will take place in Los Angeles Universal City, CA, USA from August 15 to August 17, 2017. The conference will present a selection of the lastest and most current reseach in the areas of addiction, HIV, and related treatment. 相似文献
995.
Chuang Zhu Ling-Ling Tai Xiao-chun Wan Da-xiang Li Yong-Qing Zhao 《Pharmaceutical biology》2017,55(1):2123-2128
Context: Tea (Camellia sinensis (L.) Kuntze [Theaceae]) is used to induce urination and inducing nervous excitation. Green and black teas have multifarious physiological functions. The different effects of green and black tea aqueous extracts (GTEs and BTEs) on hyperuricemia are not definitely reported.Objective: The different effects of GTEs and BTEs on lowering serum uric acid (UA) in hyperuricemic mice were determined.Materials and methods: Kunming mice were divided into nine groups (n?=?6/each group). GTEs and BTEs at the doses of 0.5, 1 and 2?g/kg were orally administrated to mice for seven days, respectively. Hepatic xanthine oxidase (XOD) and adenosine deaminase (ADA) activities as mechanisms of actions were assessed.Results: Research indicated that the LD50 of tea extract is greater than 2?g/kg in mice. UA levels were suppressed significantly with dose-dependent treatment of 0.5, 1 and 2?g/kg BTEs (up to 25.5%, 28.7% and 29.8%, respectively); the serum UA levels were decreased by GTEs but not significant. The activities of XOD and ADA in high dose (2?g/kg) groups of both GTEs and BTEs were notably lower than those of the model group.Discussion and conclusions: The results suggested that both GTEs and BTEs have hypouricaemic and renal protective effects on hyperuricemic mice and the latter one was better. Our study sheds light on the research and development of anti-hyperuricemic functional foods and drugs from tea. 相似文献
996.
Chen-Dan Zou Wei-Ming Zhao Xiao-Na Wang Qiang Li Hui Huang Wan-Peng Cheng Jian-Feng Jin He Zhang Ming-Juan Wu Sheng Tai Chao-Xia Zou Xu Gao 《Oncotarget》2016,7(1):266-278
MicroRNAs (miRNAs) are dysregulated in many types of malignancies, including human hepatocellular carcinoma (HCC). MiR-107 has been implicated in several types of cancer regulation; however, relatively little is known about miR-107 in human HCC. In the present study, we showed that the overexpression of miR-107 accelerates the tumor progression of HCC in vitro and in vivo through its new target gene, CPEB3. Furthermore, our results demonstrated that CPEB3 is a newly discovered tumor suppressor that acts via the EGFR pathway. Therefore, our study demonstrates that the newly discovered miR-107/CPEB3/EGFR axis plays an important role in HCC progression and might represent a new potential therapeutic target for HCC treatment. 相似文献
997.
Terence Ng Shu Mei Teo Hui Ling Yeo Maung Shwe Yan Xiang Gan Yin Ting Cheung Koon Mian Foo Mooi Tai Cham Jung Ah Lee Yee Pin Tan Gilbert Fan Wei Sean Yong Madhukumar Preetha Wei-Jen Kiley Loh Si-Lin Koo Amit Jain Guek Eng Lee Mabel Wong Rebecca Dent Yoon Sim Yap Raymond Ng Chiea Chuen Khor Han Kiat Ho Alexandre Chan 《Neuro-oncology》2016,18(2):244-251
Background
Brain-derived neurotrophic factor (BDNF), a neurotrophin that regulates neuronal function and development, is implicated in several neurodegenerative conditions. Preliminary data suggest that a reduction of BDNF concentrations may lead to postchemotherapy cognitive impairment. We hypothesized that a single nucleotide polymorphism (rs6265) of the BDNF gene may predispose patients to cognitive impairment. This study aimed to evaluate the effect of BDNF gene polymorphism on chemotherapy-associated cognitive impairment.Methods
Overall, 145 patients receiving chemotherapy for early-stage breast cancer (mean age: 50.8 ± 8.8 y; 82.1% Chinese) were recruited. Patients'' cognitive functions were assessed longitudinally using the validated Functional Assessment of Cancer Therapy–Cognitive Function (v.3) and an objective computerized tool, Headminder. Genotyping was performed using Sanger sequencing. Logistic regression was used to evaluate the association between BDNF Val66Met polymorphism and cognition after adjusting for ethnicity and clinically important covariates.Results
Of the 145 patients, 54 (37%) reported cognitive impairment postchemotherapy. The Met/Met genotype was associated with statistically significant lower odds of developing cognitive impairment (odds ratio [OR] = 0.26; 95% CI: 0.08–0.92; P = .036). The Met carriers were less likely to experience impairment in the domains of verbal fluency (OR = 0.34; 95% CI: 0.12–0.90; P = .031) and multitasking ability (OR = 0.37; 95% CI: 0.15–0.91; P = .030) compared with the Val/Val homozygote. No associations were observed between Headminder and the BDNF Val66Met polymorphism.Conclusions
This is the first study to provide evidence that carriers of the BDNF Met allele are protected against chemotherapy-associated cognitive impairment. Further studies are required to validate the findings. 相似文献998.
999.
Serum 25-hydroxyvitamin D and bone mineral density in a racially and ethnically diverse group of men 总被引:2,自引:0,他引:2
Hannan MT Litman HJ Araujo AB McLennan CE McLean RR McKinlay JB Chen TC Holick MF 《The Journal of clinical endocrinology and metabolism》2008,93(1):40-46
CONTEXT: Although racial and ethnic differences in vitamin D status and bone mineral density (BMD) are recognized, less is known about how differences in vitamin D status impact BMD, especially among men. OBJECTIVE: Our objective was to examine the relation between serum 25-hydroxyvitamin D [25(OH)D] and BMD by race and ethnic group. DESIGN: We conducted a population-based, observational survey. Participants: Participants included 1114 Black, Hispanic, and White men, 30-79 yr of age. Outcomes: We assessed 25(OH)D by a competitive protein binding assay and BMD by dual-energy x-ray absorptiometry. RESULTS: Mean age +/- SD of the 331 Black, 362 Hispanic, and 421 White men was 48 +/- 12.8 yr. Mean 25(OH)D was lower among Black (25.0 +/- 14.7 ng/ml) and Hispanic (32.9 +/- 13.9 ng/ml) men compared with White men (37.4 +/- 14.0 ng/ml, P < 0.01). A higher percentage of both Black (44%) and Hispanic (23%) men had levels of 25(OH)D in the lowest quartile, compared with 11% of White men (P < 0.001). After adjusting for age, height, and weight, only White men showed significant positive correlation between 25(OH)D and BMD (range of correlations, 0.00-0.14). Serum 25(OH)D was not associated with BMD in Black or Hispanic men at any bone site. Results were similar when adjusted for age only. CONCLUSIONS: Our findings confirm substantial racial and ethnic group differences in BMD and serum 25(OH)D in men. Serum 25(OH)D and BMD are significantly related to one another in White men only. This may have implications for evaluation of bone health and supplementation in men with low levels of 25(OH)D. Further understanding of the biological mechanisms for these differences between race and ethnic groups is needed. 相似文献
1000.