全文获取类型
收费全文 | 46736篇 |
免费 | 4475篇 |
国内免费 | 3703篇 |
专业分类
耳鼻咽喉 | 297篇 |
儿科学 | 422篇 |
妇产科学 | 484篇 |
基础医学 | 5605篇 |
口腔科学 | 746篇 |
临床医学 | 6802篇 |
内科学 | 7070篇 |
皮肤病学 | 590篇 |
神经病学 | 2559篇 |
特种医学 | 1946篇 |
外国民族医学 | 23篇 |
外科学 | 4297篇 |
综合类 | 7662篇 |
现状与发展 | 15篇 |
一般理论 | 7篇 |
预防医学 | 2808篇 |
眼科学 | 1455篇 |
药学 | 5040篇 |
81篇 | |
中国医学 | 2829篇 |
肿瘤学 | 4176篇 |
出版年
2024年 | 94篇 |
2023年 | 767篇 |
2022年 | 1140篇 |
2021年 | 2569篇 |
2020年 | 1950篇 |
2019年 | 1647篇 |
2018年 | 1755篇 |
2017年 | 1511篇 |
2016年 | 1452篇 |
2015年 | 2167篇 |
2014年 | 2631篇 |
2013年 | 2341篇 |
2012年 | 3456篇 |
2011年 | 3886篇 |
2010年 | 2359篇 |
2009年 | 1854篇 |
2008年 | 2480篇 |
2007年 | 2630篇 |
2006年 | 2481篇 |
2005年 | 2576篇 |
2004年 | 1484篇 |
2003年 | 1330篇 |
2002年 | 1109篇 |
2001年 | 1110篇 |
2000年 | 1152篇 |
1999年 | 1210篇 |
1998年 | 793篇 |
1997年 | 818篇 |
1996年 | 636篇 |
1995年 | 572篇 |
1994年 | 528篇 |
1993年 | 316篇 |
1992年 | 386篇 |
1991年 | 325篇 |
1990年 | 289篇 |
1989年 | 253篇 |
1988年 | 232篇 |
1987年 | 204篇 |
1986年 | 153篇 |
1985年 | 112篇 |
1984年 | 50篇 |
1983年 | 40篇 |
1982年 | 19篇 |
1981年 | 14篇 |
1980年 | 15篇 |
1979年 | 13篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1966年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 265 毫秒
991.
MicroRNAs can effectively induce formation of insulin‐producing cells from mesenchymal stem cells 下载免费PDF全文
Chunyu Bai Yuhua Gao Xiangchen Li Kunfu Wang Hui Xiong Zhiqiang Shan Ping Zhang Wenjie Wang Weijun Guan Yuehui Ma 《Journal of tissue engineering and regenerative medicine》2017,11(12):3457-3468
MicroRNAs regulate insulin secretion, pancreatic development and beta cell differentiation. However, the function of microRNAs in the formation of insulin‐producing cells (IPCs) from adult stem cells is poorly understood. We examine the microRNA expression profile in nestin‐positive umbilical cord‐derived mesenchymal stem cells (N‐UCMSCs) and nestin‐positive pancreatic mesenchymal stem cells using a deep sequencing approach. We also selected specific microRNAs for overexpression in N‐UCMSCs and found that miR‐375 and miR‐26a induced IPCs differentiation from N‐UCMSCs by downregulating target genes including mtpn, sox6, bhlhe22 and ccnd1. Small interfering RNAs were also used to knock down these genes in N‐UCMSCs to induce the formation of IPCs. These results suggest that endogenous microRNAs involved in the formation of IPCs from adult stem cells show promise for advancing the development of an effective cell transplant therapy for diabetes. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
992.
Kai Gao Yinghui Hua Shiyi Chen Yunxia Li Qingfeng Xin 《Knee surgery, sports traumatology, arthroscopy》2013,21(6):1300-1303
Cancellous osteoid osteoma of the talus near the subtalar joint is rare, and the treatment is very challenging. We present the first case of arthroscopic excision of juxtaarticular cancellous osteoid osteoma in the talar neck near the subtalar joint. After confirming the nidus of the osteoid osteoma with computer tomography, the lesion was completely removed with a motorized bur under arthroscopy, and the patient’s pain disappeared immediately after surgery. This case report demonstrates that a cancellous osteoid osteoma in the talar neck near the subtalar joint can be treated by arthroscopic excision and good results could be obtained. Level of evidence IV. 相似文献
993.
A plasmid for cytoglobin expression, pAcGFP1-C1-cytoglobin, was transfected into SH-SY5Y cells. Cobalt chloride was used to establish a model of hypoxia. Western blotting indicated that cytoglobin was overexpressed and there was low expression of hypoxia-inducible factor-1α in SH-SY5Y cells after transfection. Following cobalt chloride-induced hypoxia, cytoglobin and hypoxia-inducible fac-tor-1α expression gradually increased in SH-SY5Y cells. Flow cytometry showed that with increas-ing duration of hypoxia, the proportion of normal cells significantly diminished in the transfected and non-transfected groups. The proportion of cells in the early stages of apoptosis increased. However, the proportion of apoptotic cells was significantly lower in the transfected group compared with the non-transfected group. These results demonstrate that cytoglobin and hypoxia-inducible factor-1α are strongly up-regulated by hypoxia, and that there is a strong relationship between hy-poxia-inducible factor-1α and cytoglobin during hypoxic injury. 相似文献
994.
Following peripheral nerve compression, peripheral nerve microcirculation plays important roles in regulating the nerve microenvironment and neurotrophic substances, supplying blood and oxygen and maintaining neural conduction and axonal transport. This paper has retrospectively analyzed the articles published in the past 10 years that addressed the relationship between peripheral nerve compression and changes in intraneural microcirculation. In addition, we describe changes in different peripheral nerves, with the aim of providing help for further studies in peripheral nerve microcirculation and understanding its protective mechanism, and exploring new clinical methods for treating peripheral nerve compression from the perspective of neural microcirculation. 相似文献
995.
Fang Zhao Puhong Zhang Lu Zhang Wenyi Niu Jianmei Gao Lixin Lu Caixia liu Xian Gao 《Nutrients》2015,7(4):2719-2730
In China, few people are aware of the amount and source of their salt intake. We conducted a survey to investigate the consumption and sources of dietary salt using the “one-week salt estimation method” by weighing cooking salt and major salt-containing food, and estimating salt intake during dining out based on established evidence. Nine hundred and three families (1981 adults and 971 children) with students in eight primary or junior high schools in urban and suburban Beijing were recruited. On average, the daily dietary salt intake of family members in Beijing was 11.0 (standard deviation: 6.2) g for children and adolescents (under 18 years old), 15.2 (9.1) g for adults (18 to 59 years old), and 10.2 (4.8) g for senior citizens (60 years old and over), respectively. Overall, 60.5% of dietary salt was consumed at home, and 39.5% consumed outside the home. Approximately 90% of the salt intake came from cooking (household cooking and cafeteria or restaurant cooking), while less than 10% came from processed food. In conclusion, the dietary salt intake in Beijing families far surpassed the recommended amounts by World Health Organization, with both household cooking and dining-out as main sources of salt consumption. More targeted interventions, especially education about major sources of salt and corresponding methods for salt reduction should be taken to reduce the risks associated with a high salt diet. 相似文献
996.
Ming‐Xing Xia Yang‐Lin Pan Xiao‐Bo Cai Jun Wu Dao‐Jian Gao Xin Ye Tian‐Tian Wang Bing Hu 《Digestive endoscopy》2021,33(1):179-189
997.
Yuan Gao Yu-ling Wang Dan Kong Bo Qu Xiao-jing Su Huan Li Hong-ying Pi 《中国神经再生研究》2015,10(6):1003-1008
With advances in biomedical methods, tissue-engineered materials have developed rapidly as an alternative to nerve autografts for the repair of peripheral nerve injuries. However, the materials selected for use in the repair of peripheral nerve injuries, in particular multiple injuries and large-gap defects, must be chosen carefully. Various methods and materials for protecting the healthy tissue and repairing peripheral nerve injuries have been described, and each method or material has advantages and disadvantages. Recently, a large amount of research has been focused on tissue-engineered materials for the repair of peripheral nerve injuries. Using the keywords “pe-ripheral nerve injury”, “autotransplant”, “nerve graft”, and “biomaterial”, we retrieved publications using tissue-engineered materials for the repair of peripheral nerve injuries appearing in the Web of Science from 2010 to 2014. The country with the most total publications was the USA. The institutions that were the most productive in this field include Hannover Medical School (Germany), Washington University (USA), and Nantong University (China). The total number of publications using tissue-engineered materials for the repair of peripheral nerve injuries grad-ually increased over time, as did the number of Chinese publications, suggesting that China has made many scientific contributions to this field of research. 相似文献
998.
Stacy Loeb Shomik Sengupta Mohit Butaney Joseph N. Macaluso Stefan W. Czarniecki Rebecca Robbins R. Scott Braithwaite Lingshan Gao Nataliya Byrne Dawn Walter Aisha Langford 《European urology》2019,75(4):564-567
YouTube is a social media platform with more than 1 billion users and >600 000 videos about prostate cancer. Two small studies examined the quality of prostate cancer videos on YouTube, but did not use validated instruments, examine user interactions, or characterize the spread of misinformation. We performed the largest, most comprehensive examination of prostate cancer information on YouTube to date, including the first 150 videos on screening and treatment. We used the validated DISCERN quality criteria for consumer health information and the Patient Education Materials Assessment Tool, and compared results for user engagement. The videos in our sample had up to 1.3 million views (average 45 223) and the overall quality of information was moderate. More videos described benefits (75%) than harms (53%), and only 50% promoted shared decision-making as recommended in current guidelines. Only 54% of the videos defined medical terms and few provided summaries or references. There was a significant negative correlation between scientific quality and viewer engagement (views/month p = 0.004; thumbs up/views p = 0.015). The comments section underneath some videos contained advertising and peer-to-peer medical advice. A total of 115 videos (77%) contained potentially misinformative and/or biased content within the video or comments section, with a total reach of >6 million viewers.
Patient summary
Many popular YouTube videos about prostate cancer contained biased or poor-quality information. A greater number of views and thumbs up on YouTube does not mean that the information is trustworthy. 相似文献999.
Zhang Di Tang Xiaojing Gao Yuan Yu Hongjing Wen Bin Fu Lili Song Shuwei Mei Changlin 《中华肾脏病杂志》2019,35(4):288-294
Objective To screen Oxalobacter formigenes (OxF) from fresh feces of healthy adults, and study its effect on the the prevention of calcium oxalate kidney stones. Methods OxF was screened and cultured from fresh feces of healthy adults. The rat model of calcium oxalate stone was established by esophageal gavage of 0.8% of ethylene glycol. Rats were divided into a control group and four groups of rats with ethylene glycol-induced calcium oxalate kidney stones according to random number table. Three groups were treated with 106 CFU, 107 CFU, 108 CFU viable OxF every day, respectively, for 4 weeks. The blood and 24-hour urine samples were collected to detect the serum creatinine, urea nitrogen, serum and urine calcium, phosphorus, magnesium and urine oxalate every week. At the end of the 4th week, the rats were sacrificed and the kidney tissues were stained with HE and Yasue. The deposition and content of calcium oxalate crystals were observed under a light microscope. Results The bacteria strain isolated from fresh feces of healthy adults was 100% as same as the known ATCC35274 bacteria strain, which means the strain screened is OxF. Among the 5 groups, there were no significant differences in body weight, Scr, BUN, serum calcium, blood magnesium, blood phosphorus, urinary magnesium and urinary phosphorus. The 24-hour urinary calcium excretion in the model group was significantly lower than that of the control group (P<0.05). After intervention with OxF solution, the 24-hour urinary calcium excretion in the 108 CFU OxF group was significantly higher than that in the model group (P<0.05), while there was no significant difference between the other intervention groups and the model. The oxalic acid excretion of 106 CFU OxF group and 107 CFU OxF group was lower than that of the model, but the difference did not reach statistical significance (P>0.05). The 24 h oxalic acid excretion in the 108 CFU OxF group was significantly lower than that of the model at the end of first week (P<0.05), and continued to decrease for the next 3 weeks. After 4 weeks of intervention, no crystal formation was observed in the control group under the deflection microscope, but a large amount of calcium oxalate crystals were formed in the renal cortex and renal medulla. The crystals were piled up and connected to each other. Yasue staining coincided with the calcium oxalate crystal in the same part of the kidneys. Compared with the model, there was no significant change in the score of calcium oxalate crystal in the kidneys of 106 CFU OxF group and 107 CFU OxF group, while the score of calcium oxalate crystal in the kidneys of 108 CFU OxF group was significantly lower (P<0.05). Conclusions OxF are successively screened from healthy adults. Daily administration of 108 CFU OxF can safely and effectively reduce the urinary oxalic acid excretion, prevent the formation of calcium oxalate crystals and inhibit the formation of stones in kidneys of rats. 相似文献
1000.