首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1183篇
  免费   88篇
  国内免费   18篇
耳鼻咽喉   46篇
儿科学   84篇
妇产科学   12篇
基础医学   100篇
口腔科学   27篇
临床医学   80篇
内科学   192篇
皮肤病学   27篇
神经病学   50篇
特种医学   144篇
外科学   132篇
综合类   137篇
预防医学   93篇
眼科学   4篇
药学   55篇
中国医学   39篇
肿瘤学   67篇
  2023年   8篇
  2022年   15篇
  2021年   24篇
  2020年   20篇
  2019年   18篇
  2018年   20篇
  2017年   15篇
  2016年   20篇
  2015年   29篇
  2014年   41篇
  2013年   43篇
  2012年   51篇
  2011年   50篇
  2010年   72篇
  2009年   62篇
  2008年   34篇
  2007年   39篇
  2006年   52篇
  2005年   35篇
  2004年   20篇
  2003年   29篇
  2002年   21篇
  2001年   20篇
  2000年   15篇
  1999年   24篇
  1998年   50篇
  1997年   61篇
  1996年   53篇
  1995年   38篇
  1994年   33篇
  1993年   31篇
  1992年   15篇
  1991年   10篇
  1990年   14篇
  1989年   30篇
  1988年   24篇
  1987年   21篇
  1986年   18篇
  1985年   15篇
  1984年   12篇
  1983年   5篇
  1982年   9篇
  1981年   10篇
  1980年   14篇
  1979年   7篇
  1977年   6篇
  1976年   7篇
  1966年   2篇
  1958年   4篇
  1957年   2篇
排序方式: 共有1289条查询结果,搜索用时 11 毫秒
91.
OBJECTIVES: This study examined whether Medicaid-insured women at low risk receive less adequate obstetrical care than privately insured women. METHODS: Low-risk women who were cared for by a random sample of obstetrical providers in Washington State were randomly selected. Information on all prenatal and intrapartum services was abstracted from medical records. Service information was aggregated into standardized resource-use units. Results compared Medicaid-insured women with those who were privately insured. RESULTS: Medicaid-insured women were significantly younger (22.5 years vs 26.9 years) and averaged 6% fewer visits than privately insured women. Nonetheless, Medicaid status had no meaningful association with prenatal, intrapartum, or overall resource use. Some variation occurred in individual resources received. Medicaid-insured women had 38.8% more resources expended on testing for sexually transmitted diseases. Privately insured women had more resources expended on alpha-fetoprotein testing and on amniocentesis. There were no meaningful differences in birthweight or gestational age at delivery. CONCLUSIONS: In this study of women who entered obstetrical care at low risk, similar care and resources were expended on Medicaid-insured and on privately insured women.  相似文献   
92.

Background

Malaria is one of the most important parasitic diseases in tropical and temperate regions. The aim of this study was to determine the trend of malaria in Mazandaran Province, northern Iran during 1997-2012.

Methods

This retrospective study was conducted from 1997 to 2012. The population''s study was individuals who registered at health centers of Mazandaran Province. Peripheral blood smear were prepared for each case, stained with Giemsa and examined by light microscope. In addition to demographic data, other parameters including Slide Positive Rate (SPR), Annual Parasite Incidence (API) and Annual Blood Examination Rate (ABER) were analyzed.

Results

In total, 844 cases of malaria were reported. Plasmodium vivax was predominant species with 821 cases (97.4%). The number of malaria cases increased from 1997 to 2005 and then decreased to 3 cases in 2011. Some cities had not reported any cases during last three years. The highest infection rate, 163(20.07%), was seen in 2001-02. The SPR had the highest value (0.54%) in 2004-05. The maximum API and ABER were observed in 2001-02 and 1997-98. 641(75.9%) of cases were imported from hyperendemic areas such as Afghanistan and South-eastern Iran and 94 (11.1%) malaria patients were recorded as introduced cases. The highest infection rate of malaria (21.3%) was seen in Babolsar.

Conclusion

Extensive malaria control should be continued to Mazandaran to become malaria-free region and in prevention of re-introduction stage.  相似文献   
93.
[目的]评价蒙药胃舒安对束缚-水浸应激所致大鼠胃溃疡的预防作用。[方法]将Wistar实验大鼠,分正常组、给药组和对照组3组,正常组不给药,无束缚-水浸应激压力,对照组给淀粉,给药组灌胃给蒙药胃舒安,给药剂量为0.9~1.3mL/只(82.5g/L),连续给胃舒安7d后,停食24h,建立3h束缚-水浸应激性胃溃疡模型,取胃,肉眼观察胃黏膜损伤,用Image J图像分析法测定胃黏膜溃疡面积,并进行比较。用酶联免疫吸附测定法检测胃溃疡大鼠血清转化生长因子(TGF-β1)含量并进行比较。[结果]蒙药胃舒安对3h束缚-水浸应激所致大鼠胃溃疡形成有抑制作用。胃舒安组大鼠血清TGF-β1含量明显低于对照组。[结论]蒙药胃舒安对实验大鼠束缚-水浸应激3h所致胃溃疡的形成有显著抑制作用。  相似文献   
94.
目的:观察五禽戏联合推拿治疗原发性痛经(PD)的临床疗效及对患者血清肿瘤坏死因子-α(TNF-α)、CD4+、催产素(OT)及β-内啡肽(β-EP)水平的影响.方法:选取80例PD女大学生,按随机数字表法分为对照组、五禽戏组、推拿组及五禽戏+推拿组,对照组给予田七痛经胶囊治疗,其余3组分别给予五禽戏、推拿及五禽戏+推拿...  相似文献   
95.
BACKGROUND: By 2016, the proportion of Canadians older than 65 years of age will increase to 16%, and there will be an increase in the absolute number of cases of cardiovascular disease in older Canadians. The Canadian Heart Health Surveys database provides information about this population upon which health policy related to cardiovascular disease can be based. This paper presents for the first time population-based data on the risk factors for cardiovascular disease in older Canadians. METHODS: Canadians from all 10 provinces participated in surveys of cardiovascular risk factors; health insurance registries were used as sampling frames. In each province, probability samples of 2200 adults 18 to 74 years old not living in institutions, on reserves or in military camps were asked to participate in interviews and to undergo testing at clinics for major risk factors for cardiovascular disease. RESULTS: A total of 2739 men (response rate 70%) and 2617 women (response rate 66%) aged 55 to 74 years participated in the survey and also provided follow-up clinical measurements at the clinic. Overall, 52% of participants were hypertensive, 26% had isolated systolic hypertension, and 30% had a total blood cholesterol level of 6.2 mmol/L or greater. Rates of current smoking were lower in women than men (17% v. 22%). Overall, 87% of men and 78% of women who were current smokers smoked at least 10 cigarettes per day. Only slightly more than half of participants exercised at least once a week for at least 15 minutes, and almost half had a body mass index of 27 or greater. In only 4% was no major risk factor for cardiovascular disease detected. INTERPRETATION: Significant numbers of older Canadians have one or more major risk factors for cardiovascular disease. Many of these risk factors are amenable to modification.  相似文献   
96.
癌性疼痛是肿瘤最为常见的临床症状之一,如何有效地控制癌性疼痛,改善癌症病人的生活质量,延长生存期已成为全球关注的焦点。WHO调查认为:进展期癌症和终末期癌症病人约75%~90%以疼痛为主要临床症状,经过治疗90%的癌性疼痛可缓解。单纯运用西医的三阶梯镇痛疗法会导致病人药物成瘾性及较大的毒副作用;而单纯运用中医药疗法止痛效果不甚显著。因此,将中西医疗法结合运用到治疗癌性疼痛上,将成为今后癌症病人综合治疗的重要环节,尤其近年来中医学以其独特的理论体系,辨病辨证相结合,采用中药内服、外用、针灸等方法,对癌性疼痛的治疗研究取得了满意的进展。  相似文献   
97.
98.
冠心病的发生、发展与中医体质存在密切关系.冠心病患者在遗传物质的差异、生长地域环境的不同等影响因素下表现出中医体质类型的差异性.诸多体质学研究发现冠心病患者以偏颇体质、兼夹体质为主.中医体质研究从宏观角度反映冠心病患者的疾病特质,中医体质分布规律的研究对冠心病的认识具有重要意义,本文就近10年来冠心病中医体质类型分布、...  相似文献   
99.

Background

Leishmaniasis is a worldwide disease prevalent in tropical and sub tropical countries. Many attempts have been made and different strategies have been approached to develop a potent vaccine against Leishmania. DNA immunisation is a method, which is shown to be effective in Leishmania vaccination. Leishmania Soluble Antigen (SLA) has also recently been used Leishmania vaccination.

Methods

The immunity generated by SLA and L. mexicana gp63 cDNA was compared in groups of 6 mice, which were statistically analysed by student t- test with the P-value of 0.05. SLA was administered by two different methods; intramuscular injection and injection of dendritic cells (DCs) loaded with SLA. L. mexicana gp63 cDNA was administered by the gene gun.

Results

Immunisation of BALB/c mice with L. mexicana gp63 resulted in high levels of Th1-type immune response and cytotoxic T lymphocytes (CTL) activity, which were accompanied with protection induced by the immunisation against L. mexicana infection. In contrast, administration of SLA, produced a mixed Th1/Th2-type immune responses as well as a high level of CTL activity but did not protect mice from the infection.

Conclusion

The results indicate higher protection by DNA immunisation using L. mexicana gp63 cDNA compared to SLA, which is accompanied by a high level of Th1 immune response. However, the CTL activity does not necessarily correlate with the protection induced by the vaccine. Also, gene gun immunisation is a potential approach in Leishmania vaccination. These findings would be helpful in opening new windows in Leishmania vaccine research.  相似文献   
100.
丁香水溶性化学成分的研究   总被引:2,自引:0,他引:2  
目的:研究丁香水溶性化学成分。方法:利用HP-20大孔吸附树脂、反相硅胶柱色谱、反相制备薄层色谱、制备型反相高效液相色谱进行分离,NMR和MS等方法进行结构鉴定。结果:从丁香干燥花蕾的水提物中分离鉴定了5个化合物,分别为槲皮素-3-O-葡萄糖醛酸苷(1),槲皮素-3-O-葡萄糖醛酸苷6″-甲酯(2),槲皮素-3-O-葡萄糖苷(3),丁香酚-β-芸香糖苷(4),杨梅酮(5)。结论:化合物1~4为首次从丁香属植物中分离得到。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号