全文获取类型
收费全文 | 11329篇 |
免费 | 1060篇 |
国内免费 | 314篇 |
专业分类
耳鼻咽喉 | 80篇 |
儿科学 | 237篇 |
妇产科学 | 243篇 |
基础医学 | 1414篇 |
口腔科学 | 202篇 |
临床医学 | 1268篇 |
内科学 | 2120篇 |
皮肤病学 | 147篇 |
神经病学 | 619篇 |
特种医学 | 369篇 |
外科学 | 1658篇 |
综合类 | 915篇 |
现状与发展 | 2篇 |
一般理论 | 2篇 |
预防医学 | 834篇 |
眼科学 | 352篇 |
药学 | 926篇 |
1篇 | |
中国医学 | 322篇 |
肿瘤学 | 992篇 |
出版年
2024年 | 16篇 |
2023年 | 125篇 |
2022年 | 227篇 |
2021年 | 374篇 |
2020年 | 274篇 |
2019年 | 303篇 |
2018年 | 347篇 |
2017年 | 282篇 |
2016年 | 289篇 |
2015年 | 386篇 |
2014年 | 476篇 |
2013年 | 489篇 |
2012年 | 773篇 |
2011年 | 821篇 |
2010年 | 480篇 |
2009年 | 444篇 |
2008年 | 685篇 |
2007年 | 647篇 |
2006年 | 602篇 |
2005年 | 620篇 |
2004年 | 518篇 |
2003年 | 471篇 |
2002年 | 392篇 |
2001年 | 289篇 |
2000年 | 291篇 |
1999年 | 291篇 |
1998年 | 154篇 |
1997年 | 119篇 |
1996年 | 107篇 |
1995年 | 97篇 |
1994年 | 88篇 |
1993年 | 64篇 |
1992年 | 140篇 |
1991年 | 113篇 |
1990年 | 117篇 |
1989年 | 89篇 |
1988年 | 91篇 |
1987年 | 92篇 |
1986年 | 78篇 |
1985年 | 61篇 |
1984年 | 42篇 |
1983年 | 42篇 |
1982年 | 43篇 |
1981年 | 28篇 |
1980年 | 16篇 |
1979年 | 32篇 |
1978年 | 19篇 |
1976年 | 19篇 |
1972年 | 16篇 |
1970年 | 17篇 |
排序方式: 共有10000条查询结果,搜索用时 203 毫秒
101.
Risk estimates promulgated by various radiation protection authorities in recent years have become increasingly more complex. Early "integral" estimates in the form of health effects per 0.01 person-Gy (per person-rad) or per 10(4) person-Gy (per 10(6) person-rad) have tended to be replaced by "differential" estimates which are age- and sex-dependent and specify both minimum induction (latency) and duration of risk expression (plateau) periods. These latter types of risk estimate must be used in conjunction with a life table in order to reduce them to integral form. In this paper, the life table has been used to effect a comparison of the organ and tissue risk estimates derived in several recent reports. In addition, a brief review of life-table methodology is presented and some features of the models used in deriving differential coefficients are discussed. While the great number of permutations possible with dose-response models, detailed risk estimates and proposed projection models precludes any unique result, the reduced integral coefficients are required to conform to the linear, absolute-risk model recommended for use with the integral risk estimates reviewed. 相似文献
102.
Winnie K. W. So Judy Y. W. Chan Bernard M. H. Law Kai Chow Choi Jessica Y. L. Ching Kam Leung Chan Raymond S. Y. Tang Carmen W. H. Chan Justin C. Y. Wu Stephen K. W. Tsui 《Nutrients》2021,13(2)
Rice bran exhibits chemopreventive properties that may help to prevent colorectal cancer (CRC), and a short-term rice bran dietary intervention may promote intestinal health via modification of the intestinal microbiota. We conducted a pilot, double-blind, randomised placebo-controlled trial to assess the feasibility of implementing a long-term (24-week) rice bran dietary intervention in Chinese subjects with a high risk of CRC, and to examine its effects on the composition of their intestinal microbiota. Forty subjects were randomised into the intervention group (n = 19) or the control group (n = 20). The intervention participants consumed 30 g of rice bran over 24-h intervals for 24 weeks, whilst the control participants consumed 30 g of rice powder on the same schedule. High rates of retention (97.5%) and compliance (≥91.3%) were observed. No adverse effects were reported. The intervention significantly enhanced the intestinal abundance of Firmicutes and Lactobacillus, and tended to increase the Firmicutes/Bacteroidetes ratio and the intestinal abundance of Prevotella_9 and the health-promoting Lactobacillales and Bifidobacteria, but had no effect on bacterial diversity. Overall, a 24-week rice bran dietary intervention was feasible, and may increase intestinal health by inducing health-promoting modification of the intestinal microbiota. Further larger-scale studies involving a longer intervention duration and multiple follow-up outcome assessments are recommended. 相似文献
103.
目的探讨鼻咽癌(NPC)分期及放疗对免疫与肿瘤复发、转移及肿瘤退缩的相关性.方法每位病人放疗前及放疗后各测定T细胞亚群指标一次.结果早、晚期鼻咽癌放疗前后T细胞亚群相比,除早期鼻咽癌CD3下降无统计学意义外,余CD3、CD4、CD4/CD8下降;CD8升高均有统计学意义,晚期鼻咽癌的改变尤为突出,有极显著统计学意义(P<0.001).放疗后肿瘤退缩与否的T细胞亚群测定无统计学意义.放疗后肿瘤有复发或转移者CD4、CD4/CD8下降有极显著统计学意义(P<0.001).CD8升高有统计学意义.结论T细胞亚群指标的测定,对鼻咽癌患者的免疫功能状况,放疗对免疫功能的影响,对鼻咽癌放疗后复发及转移的可能性判断均有一定的临床意义. 相似文献
104.
Potential cancer therapy with the fragile histidine triad gene: review of the preclinical studies. 总被引:9,自引:0,他引:9
CONTEXT: The fragile histidine triad gene (FHIT) encompasses a human common fragile site, FRA3B, that is susceptible to environmental carcinogens. Deletion and inactivation of FHIT have been seen in a number of human premalignant and malignant lesions. OBJECTIVE: To review and evaluate preclinical studies of cancer therapy using the FHIT tumor suppressor gene and related studies involving Fhit protein expression. DATA SOURCES: A MEDLINE search of articles published from 1996 to June 2001 was performed; article reference lists were used to retrieve additional relevant articles. STUDY SELECTION: Immunohistochemical studies of primary tumors or relevant lesions were selected to evaluate Fhit expression in premalignant or malignant stages. Preclinical studies on antitumorigenic or therapeutic introduction of FHIT were reviewed for the effects of exogenous Fhit expression. For the immunohistochemical analyses, 26 studies were included that analyzed at least 15 cases of a single type of tumor. For precancerous lesions, 9 studies were included that analyzed at least 4 cases. For studies of FHIT introduction, 9 published studies were included. DATA EXTRACTION: Using primary data from each of the studies, we assessed the rationale and potential contribution of FHIT cancer therapy. Data was independently abstracted by 2 authors and study quality was assessed by 2 other authors. DATA SYNTHESIS: Overall, 60% (1162/1948 cases) of primary tumors showed absent or markedly reduced Fhit protein expression in cancer cells. Studies of preneoplastic lesions or early-stage cancer showed absence or marked reduction of Fhit protein expression in 0% to 93% of samples (overall, 31% [127/408 cases]). Preclinical studies using 26 cancer-derived cell lines from human lung, head and neck, esophageal, gastric, cervical, pancreatic, and kidney cancers, showed that reintroduction of FHIT resulted in inhibition of in vitro tumor cell growth or of in vivo tumorigenicity in 17 (57%) of 30 cell line experiments. Model systems for human preventive cancer therapy suggested that oral introduction of viral vector-mediated FHIT into Fhit-deficient mice may prevent carcinogen-induced tumor development in some cases. CONCLUSION: These findings show that FHIT gene therapy may potentially be clinically useful for treatment of cancer and also prevention of carcinogen-induced tumor development, suggesting a rationale for further research involving FHIT introduction. 相似文献
105.
Thomas Powles Michael B. Atkins Bernard Escudier Robert J. Motzer Brian I. Rini Lawrence Fong Richard W. Joseph Sumanta K. Pal Mario Sznol John Hainsworth Walter M. Stadler Thomas E. Hutson Alain Ravaud Sergio Bracarda Cristina Suarez Toni K. Choueiri James Reeves Allen Cohn David F. McDermott 《European urology》2021,79(5):665-673
BackgroundThe use of immune checkpoint inhibitors combined with vascular endothelial growth factor (VEGF)-targeted therapy as second-line treatment for metastatic clear cell renal cancer (mRCC) has not been evaluated prospectively.ObjectiveTo evaluate the efficacy and safety of atezolizumab + bevacizumab following disease progression on atezolizumab or sunitinib monotherapy in patients with mRCC.Design, setting, and participantsIMmotion150 was a multicenter, randomized, open-label, phase 2 study of patients with untreated mRCC. Patients randomized to the atezolizumab or sunitinib arm who had investigator-assessed progression as per RECIST 1.1 could be treated with second-line atezolizumab + bevacizumab.InterventionPatients received atezolizumab 1200 mg intravenously (IV) plus bevacizumab 15 mg/kg IV every 3 wk following disease progression on either atezolizumab or sunitinib monotherapy.Outcome measurements and statistical analysisThe secondary endpoints analyzed during the second-line part of IMmotion150 included objective response rate (ORR), progression-free survival (PFS), and safety. PFS was examined using Kaplan-Meier methods.Results and limitationsFifty-nine patients in the atezolizumab arm and 78 in the sunitinib arm were eligible, and 103 initiated second-line atezolizumab + bevacizumab (atezolizumab arm, n = 44; sunitinib arm, n = 59). ORR (95% confidence interval [CI]) was 27% (19–37%). The median PFS (95% CI) from the start of second line was 8.7 (5.6–13.7) mo. The median event follow-up duration was 19.4 (12.9–21.9) mo among the 25 patients without a PFS event. Eighty-six (83%) patients had treatment-related adverse events; 31 of 103 (30%) had grade 3/4 events. Limitations were the small sample size and selection for progressors.ConclusionsThe atezolizumab + bevacizumab combination had activity and was tolerable in patients with progression on atezolizumab or sunitinib. Further studies are needed to investigate sequencing strategies in mRCC.Patient summaryPatients with advanced kidney cancer whose disease had worsened during treatment with atezolizumab or sunitinib began second-line treatment with atezolizumab + bevacizumab. Tumors shrank in more than one-quarter of patients treated with this combination, and side effects were manageable. 相似文献
106.
Qi Chen Jiaming Feng Zhidan Liu Dongyang An Yadan Li Shaohu Zhou Zhiwei Weng 《Andrologia》2021,53(10):e14206
In the past two decades, thousands of documents in the field of prostatitis have been published. This bibliometric analysis aimed to assess the characteristics, hotspots and frontiers trend of global scientific output on prostatitis. With the trend of moderate growth, altogether 2,423 papers were reviewed. The leading role of the United States in global prostatitis research was obvious, while China had developed rapidly in recent years. Queen's University and JOURNAL OF UROLOGY were the most prolific affiliation and journal respectively. Nickel, J. C made the greatest contribution to the field of prostatitis. Five hotspots have been confirmed: (a) male infertility associated with prostatitis and the molecular mechanisms; (b) diagnosis and treatment of prostatitis; (c) inflammation, pain and bladder irritation symptoms; (d) relationship between chronic prostatitis/chronic pelvic pain syndrome, benign prostatic hyperplasia and prostate cancer; (e) epidemiology, complications of prostatitis and improvement of acupuncture. This bibliometric analysis reveals that the international cooperation was becoming more and more close. Hotspot analysis shows that the molecular mechanism of prostatitis will be a hotspot in the future, mainly focussing on inflammatory immunity and oxidative stress. 相似文献
107.
108.
Fong Zhi Ven Sekigami Yurie Qadan Motaz Fernandez-del Castillo Carlos Warshaw Andrew L. Lillemoe Keith D. Ferrone Cristina R. 《Annals of surgical oncology》2021,28(8):4216-4224
Annals of Surgical Oncology - Long-term pancreatoduodenectomy (PD) survivors have previously reported favorable quality of life (QoL). However, there has been a paucity of studies utilizing... 相似文献
109.
110.
Charles Varnell Jr Lyndsay A. Harshman Laurie Smith Chunyan Liu Shiran Chen Samhar Al-Akash Gina-Marie Barletta Craig Belsha Paul Brakeman Abanti Chaudhuri Paul Fadakar Rouba Garro Caroline Gluck Jens Goebel David Kershaw Debora Matossian Corina Nailescu Hiren P. Patel Cozumel Pruette Saritha Ranabothu Nancy Rodig Jodi Smith Judith Sebestyen VanSickle Patricia Weng Lara Danziger-Isakov David K. Hooper Michael Seifert 《American journal of transplantation》2021,21(8):2740-2748
There are limited data on the impact of COVID-19 in children with a kidney transplant (KT). We conducted a prospective cohort study through the Improving Renal Outcomes Collaborative (IROC) to collect clinical outcome data about COVID-19 in pediatric KT patients. Twenty-two IROC centers that care for 2732 patients submitted testing and outcomes data for 281 patients tested for SARS-CoV-2 by PCR. Testing indications included symptoms and/or potential exposures to COVID-19 (N = 134, 47.7%) and/or testing per hospital policy (N = 154, 54.8%). Overall, 24 (8.5%) patients tested positive, of which 15 (63%) were symptomatic. Of the COVID-19-positive patients, 16 were managed as outpatients, six received non-ICU inpatient care and two were admitted to the ICU. There were no episodes of respiratory failure, allograft loss, or death associated with COVID-19. To estimate incidence, subanalysis was performed for 13 centers that care for 1686 patients that submitted all negative and positive COVID-19 results. Of the 229 tested patients at these 13 centers, 10 (5 asymptomatic) patients tested positive, yielding an overall incidence of 0.6% and an incidence among tested patients of 4.4%. Pediatric KT patients in the United States had a low estimated incidence of COVID-19 disease and excellent short-term outcomes. 相似文献