全文获取类型
收费全文 | 19967篇 |
免费 | 1459篇 |
国内免费 | 409篇 |
专业分类
耳鼻咽喉 | 121篇 |
儿科学 | 599篇 |
妇产科学 | 324篇 |
基础医学 | 1606篇 |
口腔科学 | 675篇 |
临床医学 | 1830篇 |
内科学 | 2793篇 |
皮肤病学 | 238篇 |
神经病学 | 1557篇 |
特种医学 | 1467篇 |
外国民族医学 | 1篇 |
外科学 | 1945篇 |
综合类 | 1630篇 |
现状与发展 | 1篇 |
一般理论 | 2篇 |
预防医学 | 3445篇 |
眼科学 | 245篇 |
药学 | 1612篇 |
5篇 | |
中国医学 | 334篇 |
肿瘤学 | 1405篇 |
出版年
2024年 | 94篇 |
2023年 | 336篇 |
2022年 | 518篇 |
2021年 | 663篇 |
2020年 | 766篇 |
2019年 | 729篇 |
2018年 | 663篇 |
2017年 | 691篇 |
2016年 | 701篇 |
2015年 | 639篇 |
2014年 | 1193篇 |
2013年 | 1394篇 |
2012年 | 1110篇 |
2011年 | 1205篇 |
2010年 | 881篇 |
2009年 | 917篇 |
2008年 | 882篇 |
2007年 | 973篇 |
2006年 | 847篇 |
2005年 | 847篇 |
2004年 | 752篇 |
2003年 | 709篇 |
2002年 | 546篇 |
2001年 | 432篇 |
2000年 | 353篇 |
1999年 | 308篇 |
1998年 | 285篇 |
1997年 | 230篇 |
1996年 | 180篇 |
1995年 | 211篇 |
1994年 | 206篇 |
1993年 | 173篇 |
1992年 | 203篇 |
1991年 | 164篇 |
1990年 | 104篇 |
1989年 | 105篇 |
1988年 | 118篇 |
1987年 | 83篇 |
1986年 | 76篇 |
1985年 | 111篇 |
1984年 | 74篇 |
1983年 | 53篇 |
1982年 | 64篇 |
1981年 | 51篇 |
1980年 | 44篇 |
1979年 | 27篇 |
1978年 | 40篇 |
1977年 | 31篇 |
1976年 | 15篇 |
1975年 | 11篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
The relationship between dietary fat intake and risk of colorectal cancer: evidence from the combined analysis of 13 case-control studies 总被引:3,自引:0,他引:3
Geoffrey R. Howe Kristan J. Aronson Enrique Benito Roberto Castelleto Jacqueline Cornée Stephen Duffy Richard P. Gallagher José M. Iscovich Jiao Deng-ao Rudolf Kaaks Gabriel A. Kune Susan Kune Hin P. Lee Marion Lee Anthony B. Miller Ruth K. Peters John D. Potter Elio Riboli Martha L. Slattery Dimitrios Trichopoulos Albert Tuyns Anastasia Tzonou Lyndsey F. Watson Alice S. Whittemore Anna H. Wu-Williams Zheng Shu 《Cancer causes & control : CCC》1997,8(2):215-228
The objective of this study was to examine the effects of the intakeof dietary fat upon colorectal cancer risk in a combined analysis of datafrom 13 case-control studies previously conducted in populations withdiffering colorectal cancer rates and dietary practices. Original datarecords for 5,287 cases of colorectal cancer and 10,470 controls werecombined. Logistic regression analysis was used to estimate odds ratios (OR)for intakes of total energy, total fat and its components, and cholesterol.Positive associations with energy intake were observed for 11 of the 13studies. However, there was little, if any, evidence of anyenergy-independent effect of either total fat with ORs of 1.00, 0.95, 1.01,1.02, and 0.92 for quintiles of residuals of total fat intake (P trend =0.67) or for saturated fat with ORs of 1.00, 1.08, 1.06, 1.21, and 1.06 (Ptrend = 0.39). The analysis suggests that, among these case-control studies,there is no energy-independent association between dietary fat intake andrisk of colorectal cancer. It also suggests that simple substitution of fatby other sources of calories is unlikely to reduce meaningfully the risk ofcolorectal cancer. 相似文献
62.
U. Eiholzer P. Bodmer M. Bühler U. Döhmann G. Meyer P. Reinhard G. Schimert G. Varga R. Wälli R. Largo L. Molinari 《European journal of pediatrics》1998,157(7):547-552
A longitudinal growth study with monthly measurements during the 1st year of life was conducted by nine paediatricians working
in private practice in Zurich. Of 92 children, none was lost to the study and only 32 of 1104 planned visits were missed;
the quality of the measurements was comparable to that of a specialised university clinic. Compared to the Zurich Longitudinal
Growth Studies, children of this study were considerably heavier and taller. In 92% of the subjects, growth velocity was at
least once outside the reference range (3rd–97th percentile). For weight increments, the corresponding proportion was 87%.
Conclusions The data indicate that current standards for the 1st year of life for the Zurich area might no longer be appropriate and
need to be updated. The currently used velocity percentiles based on 3-monthly measurements are not suitable to assess individual
height and weight increments calculated from monthly measurements.
Received: 9 June 1997 / Accepted in revised form: 21 November 1997 相似文献
63.
目的 探讨影响极低出生体重儿(VLBWI)体重增长的院内相关因素.方法 对1998年1月至2007年12月我院新生儿重症监护病房(NICU)收治的151例VLBWI进行回顾性分析.根据出院时体重是否达到纠正胎龄第10百分位数分为迟缓组和非迟缓组,分别为104例和47例.结果 两组之间胎龄、出生体重、恢复出生体重日龄、体重下降百分比、日平均体重增长差异均有统计学意义.生后第1、2周迟缓组摄人热量、胃肠内摄入热量、多种氨基酸和总入量均低于非迟缓组,差异有统计学意义.Logistic回归分析发现胎龄(OR=0.140,95%CI 0.051~0.385,P=0.000)、出生体重(OR=1.016,95%CI 1.006~1.026,P=0.002)、第1周多种氨基酸量(OR=47.565,95%CI 1.386~1632.621,P=0.032)和第1周胃肠内热量(OR=23.643,95%CI 1.211~234.877,P=0.042)是影响体重增长的危险因素.结论 VLBWI生后应保证足够的热量、多种氨基酸和总入量,小于胎龄儿和有严重并发症的患儿更应加强营养,合理应用胃肠外营养. 相似文献
64.
Silica-containing dust and silicosis have beenattracting more and more attention with numerousresearches worldwide[1 ,2], especially in China .However ,few studies have been conducted con-cerning the criteria of the period and content ofmedical examination of health surveillance for dust-exposed workers[3]. Since 1986 an epidemiologicalstudy onthe relation of silica dust exposure ,silico-sis and lung cancer was jointly made by TongjiMedical College , US National Cancer Institute andthe US … 相似文献
65.
Episode-related factors and antidepressant treatment adequacy may be important determinants of recovery from a major depressive episode (MDE). We compared recovered and nonrecovered patients on baseline sociodemographic, clinical and episode-related measurements. Twenty-five inpatients with recurrent major depressive disorder diagnosed by SADS-L participated in this naturalistic, prospective, longitudinal study. Recovery, which was defined as a sustained return to non-depressed status lasting > or = 8 consecutive weeks, was assessed at 6- and 12-month follow-up with the Streamlined Longitudinal Interval Continuation Evaluation (SLICE). Thirteen (52%) patients met recovery criteria. The cumulative proportion remaining depressed for at least 52 weeks was 42.5%. Recovered patients had shorter episodes preceding the index hospitalization (P = .01). Despite adequate antidepressant pharmacotherapy, the length of the current episode remains the most important correlate of recovery from MDE recurrence. Our small sample size and the uncontrolled nature of treatment may limit the generalizability of these findings. 相似文献
66.
795例肠外营养支持的回顾性分析 总被引:2,自引:0,他引:2
目的:对795例患者的肠外营养支持进行回顾性分析.方法:对行肠外营养支持的399例患者进行治疗前后淋巴细胞计数、血浆白蛋白和血浆锌离子浓度等营养学指标的比较,并选择行肠外营养的患者198例与行单一静脉营养的患者198例进行营养学指标的比较,同时比较不良反应和依从性.另选择25例有单一静脉营养史患者25例,分为足量组13例和低氮组12例,分别按照1.0~1.5和0.6 g·kg-1·d-1逐渐在3 d内递增到1.0~1.5 g·kg-1·d-1给予氨基酸,其余营养支持相同, 进行营养学指标的比较.结果:与治疗前比较,行肠外营养支持后患者的白蛋白、淋巴细胞计数、锌离子浓度等均显著增加(P<0.05).与单一静脉营养相比较,行肠外营养患者的白蛋白、淋巴细胞计数、锌离子浓度等也均显著增加(P<0.05),同时不良反应和依从性较好.足量组与低氮组比较,白蛋白值显著增加,而淋巴细胞计数、锌离子浓度无显著性差异.结论:肠外营养支持可以显著改善营养不良. 相似文献
67.
68.
Nicole-Ann Lim Ooiean Teng Chester Yan Hao Ng Lena X. Y. Bao Paul Anantharajah Tambyah Amy M. L. Quek Raymond C. S. Seet 《Annals of medicine》2022,54(1):1488
BackgroundAccumulating data suggest antiviral effects of povidone-iodine against the Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. This narrative review aims to examine the antiviral mechanisms of povidone-iodine, efficacy of povidone-iodine against the SARS-CoV-2 virus, and safety of povidone-iodine to human epithelial cells and thyroid function.MethodsWe searched the electronic databases PubMed, Embase, Cochrane Library, ClinicalTrials.gov and World Health Organization’s International Clinical Trials Registry Platform for articles containing the keywords “povidone-iodine”, “SARS-CoV-2” and “COVID-19” from database inception till 3 June 2021.ResultsDespite in vitro data supporting the anti-SARS-CoV-2 effects of povidone-iodine, findings from clinical studies revealed differences in treatment response depending on study settings (healthy vs. hospitalized individuals), treatment target (nasal vs. oral vs. pharynx), method of administration (oral rinse vs. gargle vs. throat spray) and choice of samples used to measure study endpoints (nasopharyngeal vs. saliva). One large-scale clinical trial demonstrated reduction in the incidence of SARS-CoV-2 infection among participants who administered povidone-iodine 3 times daily during an active outbreak. Povidone-iodine is also used to disinfect the oro-pharyngeal space prior to dental or otolaryngology procedures. Although existing data suggest minimal impact of povidone-iodine on thyroid function, high-quality safety data are presently lacking.ConclusionsPovidone-iodine application to the oropharyngeal space could complement existing non-pharmacological interventions to reduce SARS-CoV-2 infection especially in high exposure settings.
Key messages
- Accumulating data suggest antiviral effects of povidone-iodine against the SARS-CoV-2 virus.
- Findings from clinical studies reveal differences in treatment response depending on study settings, treatment target, method of administration and choice of samples used to measure study endpoints. One large-scale clinical trial observed reduction in the incidence of SARS-CoV-2 infection among participants who administered povidone-iodine 3 times daily during an active outbreak.
- Povidone-iodine application to the oropharyngeal space could complement existing non-pharmacological interventions to reduce SARS-CoV-2 infection especially in high exposure settings.
69.
目的探讨综合干预措施对老年人血脂异常状况改善的价值。方法采用国际标准化心血管流行病学调查方法,对辖区内离退休老干部进行心血管危险因素调查;对该人群进行健康教育,并对每一个体进行危险评估、个体化用药指导,并跟踪随访。结果(1)本研究人群是多重危险因素高度聚集的心血管疾病群体,冠心病及等危症者占69.81%;(2)经过3年的综合干预,他汀类药物的服用率由14.48%上升到22.32%;高TC血症治疗达标率由27.00%上升至63.78%;高LDL-C控制率由19.79%上升到63.65%;TC与LDL-C的达标率都有显著增高(P<0.01);TG的达标率无显著变化。结论健康教育和根据危险分层确定个体化治疗方案相结合的综合干预,能够明显提高高胆固醇血症老年患者的血脂达标率。 相似文献
70.
傅金阶 《中国临床保健杂志》2007,10(6):591-592
目的探讨中枢神经系统(CNS)感染的诊断及鉴别诊断思路。方法回顾性分析以发热、头痛、神经系统功能缺损为首发症状,初诊疑诊CNS感染的住院患者103例,分析误诊原因。结果(1)确诊CNS感染92例,非CNS感染误诊CNS感染为8例,诊断不明3例。(2)CNS感染各病种之间的误诊以病毒性脑炎、结核性脑膜炎、脑肿瘤多见。结论对CNS感染临床诊治思路应遵循多发病多考虑,少发病少考虑的原则;尽早选择CSF检查,有助于早期诊断。 相似文献