全文获取类型
收费全文 | 4608097篇 |
免费 | 344111篇 |
国内免费 | 10996篇 |
专业分类
耳鼻咽喉 | 65812篇 |
儿科学 | 150190篇 |
妇产科学 | 126354篇 |
基础医学 | 644488篇 |
口腔科学 | 133826篇 |
临床医学 | 427426篇 |
内科学 | 884104篇 |
皮肤病学 | 102718篇 |
神经病学 | 379492篇 |
特种医学 | 178497篇 |
外国民族医学 | 1801篇 |
外科学 | 690350篇 |
综合类 | 105447篇 |
现状与发展 | 7篇 |
一般理论 | 1974篇 |
预防医学 | 370956篇 |
眼科学 | 108854篇 |
药学 | 342872篇 |
12篇 | |
中国医学 | 9062篇 |
肿瘤学 | 238962篇 |
出版年
2018年 | 49560篇 |
2017年 | 37976篇 |
2016年 | 43035篇 |
2015年 | 48496篇 |
2014年 | 68346篇 |
2013年 | 104273篇 |
2012年 | 139541篇 |
2011年 | 148511篇 |
2010年 | 89141篇 |
2009年 | 84543篇 |
2008年 | 139348篇 |
2007年 | 148348篇 |
2006年 | 149719篇 |
2005年 | 145116篇 |
2004年 | 140189篇 |
2003年 | 135175篇 |
2002年 | 131435篇 |
2001年 | 206494篇 |
2000年 | 212723篇 |
1999年 | 180934篇 |
1998年 | 54847篇 |
1997年 | 48676篇 |
1996年 | 48034篇 |
1995年 | 46439篇 |
1994年 | 43175篇 |
1993年 | 40508篇 |
1992年 | 144147篇 |
1991年 | 140088篇 |
1990年 | 135929篇 |
1989年 | 131519篇 |
1988年 | 121542篇 |
1987年 | 119857篇 |
1986年 | 113202篇 |
1985年 | 108751篇 |
1984年 | 82048篇 |
1983年 | 70216篇 |
1982年 | 42172篇 |
1981年 | 38234篇 |
1979年 | 75912篇 |
1978年 | 53741篇 |
1977年 | 45794篇 |
1976年 | 42948篇 |
1975年 | 45564篇 |
1974年 | 55150篇 |
1973年 | 52755篇 |
1972年 | 49606篇 |
1971年 | 45972篇 |
1970年 | 43220篇 |
1969年 | 40647篇 |
1968年 | 37420篇 |
排序方式: 共有10000条查询结果,搜索用时 184 毫秒
991.
992.
Nathan Scudder James Robertson Sally F. Kelty Simon J. Walsh Dennis McNevin 《The Australian journal of forensic sciences》2020,52(2):235-241
ABSTRACTForensic DNA analysis is dependent on comparing the known and the unknown. Expand the number of known profiles, and the likelihood of a successful match increases. Forensic use of DNA is moving towards comparing samples of unknown origin with publicly available genetic data, such as the records held by genetic genealogy providers. Use of forensic genetic genealogy has yielded a number of recent high-profile successes but has raised ethical and privacy concerns. Navigating family trees is complex, even more so when combined with a comparison of genetic relationships. This intelligence-gathering process has led to occasional false leads, and its use also risks a public backlash, similar to concerns over Cambridge Analytica. A cautious approach to use of this technique is therefore warranted. 相似文献
993.
994.
B. G. Salas-Salas D. J. Domnguez-Nuez R. Cabrera L. Ferrera-Alayn M. Lloret P. C. Lara 《Clinical & translational oncology》2020,22(1):151-157
Definitive radiotherapy is an effective single-modality in T1 glottic cancer. Hypofractionated schemes could offer excellent results in a shorter treatment period. We aimed to evaluate the clinical outcomes and toxicity comparing conventional vs. hypofractionated radiotherapy treatment in T1N0M0-glottic cancer. Between Jan-1st, 2005 and August-1st, 2017, in a prospective cohort study, with 10-year follow-up, 138 patients were treated with conventional schedule 2 Gy/day, total dose 70 Gy/7 weeks (N = 71) or hypofractionated schedule 2, 2–2, 25 Gy/day, total dose 63, 8–63 Gy/5, 5 weeks (N = 67). Endpoints were clinical-response rate, local relapse-free survival (LRFS), laryngectomy-free survival (LFS), toxicity rates, relapse-free survival (RFS), metastasis-free survival (MFS), second tumour-free survival (2TFS), and overall survival (OS). All patients showed a complete clinical response. No differences were found for LRFS (p = 0.869), LFS (p = 0.975), RFS (p = 0.767), MFS (p = 0.601), 2TFS (p = 0.293), or OS (p = 0.685). Acute toxicity for skin and mucosae was similar (p = 0.550 and p = 0.698). Acute laryngeal toxicity was higher in the hypofractionation group (p = 0.004), due to an increase in slight moderate grade. No differences in late laryngeal edema were found (p = 0.989). Radiotherapy offers high rate survival, local control, and larynx preservation after 5–10-year follow-up. A hypofractionation could be preferable, since it offers the same results as conventional with fewer treatment sessions. 相似文献
995.
996.
997.
Lars J Vatten Tom I L Nilsen P?l R Romundstad Wenche B Dr?yvold Jostein Holmen 《European journal of cardiovascular prevention and rehabilitation》2006,13(6):909-915
OBJECTIVE: To investigate whether cardiovascular mortality related to obesity could be modified by physical activity. DESIGN: Mortality follow-up. SETTING: Population study. PARTICIPANTS: Participants in a health survey: 34 868 women and 32 872 men free from known cardiovascular disease or diabetes at baseline. MAIN OUTCOME MEASURES: Total cardiovascular mortality. MAIN RESULTS: During 16 years of follow-up, 3026 women and 3526 men had died from cardiovascular causes. In middle age, obesity [body mass index (BMI) of 30 or higher] was associated with increased risk of cardiovascular death, but the association weakened with age. After 70, there was no association between BMI and cardiovascular death. At all ages, a lower level of physical activity was associated with a higher cardiovascular mortality. In women with high physical activity, indicated by at least 30 min of moderate to vigorous activity more than once a week, cardiovascular mortality was only slightly higher in the obese compared to lean women (adjusted relative risk, 1.27; 95% confidence interval, 0.80-2.00). In men with high physical activity, cardiovascular mortality was, however, significantly higher among the obese (relative risk, 1.62; 95% confidence interval, 1.09-2.40). In both genders cardiovascular mortality was substantially higher in obese people who reported no regular physical activity compared to obese people with a high level of physical activity. CONCLUSION: In obese women, being highly active may, to a large extent, compensate for the risk-increasing effect of being obese, whereas in obese men who engage in a high level of physical activity, the risk of cardiovascular death may be higher than in lean and equally active men. 相似文献
998.
Timothy W Puetz Kathryn M Beasman Patrick J O'Connor 《European journal of cardiovascular prevention and rehabilitation》2006,13(6):886-893
BACKGROUND: Physical activity is a healthful behavior that has promise for combating feelings of low energy and fatigue. Despite evidence suggesting that fatigue is a prodromal symptom of major cardiac events, improvements in feelings of energy and fatigue have largely been ignored by reviewers of cardiac rehabilitation literature who have focused on anxiety, depression and general measures of quality of life. DESIGN: A meta-analytical review. METHODS AND RESULTS: Computer databases were searched from January 1945 to May 2005 to identify relevant literature. A total of 36 studies consisting of 4765 subjects were included. Cardiac rehabilitation exercise programs were consistently associated with increases in energy and decreases in fatigue. The magnitude of the effect was moderately large (mean delta 0.51; 95% confidence interval 0.42-0.61) but was heterogeneous and modified by features of the research design. Comparison of effect sizes in cardiac rehabilitation studies concurrently measuring energy/fatigue, anxiety and depression suggest that exercise-based cardiac rehabilitation programs have larger effects on feelings of energy and fatigue compared with anxiety and depression. CONCLUSION: This review quantifies the potential benefit of cardiac rehabilitation exercise programs on feelings of energy and fatigue, and suggests that cardiac rehabilitation researchers and practitioners may benefit from examining, and perhaps even focusing on, feelings of energy and fatigue as an important outcome variable. A greater understanding of the effect of cardiac rehabilitation exercise programs on feelings of energy and fatigue will be reached when more true experiments are conducted thereby avoiding the primary limitation of the literature reviewed; that is, the frequent use of non-experimental research designs. 相似文献
999.
Heather M Arthur Christine Patterson James A Stone 《European journal of cardiovascular prevention and rehabilitation》2006,13(1):3-9
BACKGROUND: Presently, complementary and alternative medicine, including both therapies and herbal/oral supplements, is used globally. Few studies have examined the use of specific therapies, separate from herbal/oral supplements, in cardiac rehabilitation. This paper presents a systematic evaluation of current research evidence related to use of specific complementary and alternative medicine therapies in secondary prevention of cardiovascular disease, with a view to making recommendations for cardiac rehabilitation. DESIGN AND METHODS: A literature search was conducted using complementary and alternative medicine websites, Medline, Allied and Complementary Medicine, CINAHL, Cochrane databases, EMBASE, SportDiscus, Clinical Evidence, and Evidence-Based Practice to locate research-based scientific evidence related to the use of complementary and alternative medicine in cardiac rehabilitation. Search keywords included heart, cardiac, cardiovascular, coronary, myocardial and rehabilitation, combined with particular therapies. Herbal/oral supplements were not included in this evaluation. RESULTS: Some complementary and alternative medicine therapies may be useful to patients by themselves or coupled with traditional cardiac rehabilitation. Tai chi, as a complement to existing exercise interventions, can be utilized for low and intermediate risk patients. transcendental meditation may be used as a stress reduction technique. There was insufficient evidence found for the use of acupuncture or chelation therapy in cardiac rehabilitation or secondary prevention. CONCLUSIONS: Some complementary and alternative medicine therapies hold promise for patients in cardiac rehabilitation. Further research is essential, however, in all areas of complementary and alternative medicine to confirm its usefulness as an adjunct to cardiac rehabilitation. 相似文献
1000.
A. Zampieron M. Elseviers P. Ormandy H. Vlaminck J.‐Y. De Vos T. Kafkia E. Lindley M. Harrington 《Journal of Renal Care》2006,32(1):14-19
This paper describes a study to capture the key roles and activities of nephrology nurses across different countries in Europe. The concept of the study and the need to clarify the activities of the nephrology nurse arose as part of a larger study to develop the European Practice Database (EPD) (1). The Research Board (EDTNA/ERCA) needed to identify key questions that would detect significant differences in the role and responsibilities of nephrology nurses in different countries and monitor the evolution over time of nephrology nursing practice in Europe. It was therefore appropriate to devise a separate small study to generate evidence based questions for the EPD and confirm the reliability and usefulness of the information captured. 相似文献