全文获取类型
收费全文 | 347251篇 |
免费 | 23405篇 |
国内免费 | 7646篇 |
专业分类
耳鼻咽喉 | 4116篇 |
儿科学 | 9624篇 |
妇产科学 | 6589篇 |
基础医学 | 28041篇 |
口腔科学 | 11994篇 |
临床医学 | 37409篇 |
内科学 | 43346篇 |
皮肤病学 | 4611篇 |
神经病学 | 19634篇 |
特种医学 | 7994篇 |
外国民族医学 | 32篇 |
外科学 | 37069篇 |
综合类 | 51053篇 |
现状与发展 | 13篇 |
一般理论 | 29篇 |
预防医学 | 35516篇 |
眼科学 | 5426篇 |
药学 | 30364篇 |
374篇 | |
中国医学 | 30599篇 |
肿瘤学 | 14469篇 |
出版年
2023年 | 5606篇 |
2022年 | 9944篇 |
2021年 | 13548篇 |
2020年 | 12689篇 |
2019年 | 18403篇 |
2018年 | 16112篇 |
2017年 | 13005篇 |
2016年 | 10567篇 |
2015年 | 9922篇 |
2014年 | 20153篇 |
2013年 | 21712篇 |
2012年 | 18405篇 |
2011年 | 19965篇 |
2010年 | 16030篇 |
2009年 | 14742篇 |
2008年 | 14402篇 |
2007年 | 14851篇 |
2006年 | 12978篇 |
2005年 | 11226篇 |
2004年 | 9166篇 |
2003年 | 8107篇 |
2002年 | 6377篇 |
2001年 | 5750篇 |
2000年 | 4732篇 |
1999年 | 4084篇 |
1998年 | 3368篇 |
1997年 | 3221篇 |
1996年 | 2790篇 |
1995年 | 2664篇 |
1994年 | 2567篇 |
1993年 | 2062篇 |
1992年 | 2100篇 |
1991年 | 1809篇 |
1990年 | 1627篇 |
1989年 | 1440篇 |
1988年 | 1352篇 |
1987年 | 1187篇 |
1985年 | 3844篇 |
1984年 | 4839篇 |
1983年 | 3383篇 |
1982年 | 3842篇 |
1981年 | 3588篇 |
1980年 | 3188篇 |
1979年 | 2939篇 |
1978年 | 2568篇 |
1977年 | 1943篇 |
1976年 | 2186篇 |
1975年 | 1662篇 |
1974年 | 1463篇 |
1973年 | 1307篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Summary During the period 1980 through 1989 a total of 1029 cases of fatal poisoning (638 men and 391 women) were examined at the Department of Forensic Medicine, Aarhus University, Denmark. In 68% of the cases death had been caused by drugs, whereas acute alcohol poisoning and carbon monoxide accounted for 15% and 14% of the cases, respectively. Alcohol was detected in more than half of the 1029 fatal poisoning cases, and in 42% of all cases the blood alcohol concentration was above 0.8 g/kg. In 57% of the cases death was categorized as accidental, only in 31% of the cases as suicide. Accidental deaths were especially predominant amongst drug and/or alcohol abusers. Propoxyphene was the drug found to have caused most fatal poisonings during the decade (30% of the drug-related deaths). Most of the propoxyphene-related deaths occurred during the early and mid-eighties. Barbiturate poisonings were quite frequent during the first half of the eighties. However, the number of deaths caused by barbiturates decreased significantly after 1986, when most barbiturates were withdrawn from the market. The number of deaths caused by narcotics and analgesics increased during the survey period, while no specific tendency was observed concerning antidepressants. 相似文献
993.
Magnetic resonance angiography (MRA) of the circle of Willis: a prospective comparison with conventional angiography in 54 subjects 总被引:4,自引:0,他引:4
We prospectively correlated the findings of magnetic resonance angiography (MRA) with those of transfemoral four-vessel angiography in 54 patients to investigate the direction of flow within the circle of Willis. Our primary goal was to assess the direction of flow using the size of the vessel and signal intensity, without saturation techniques. Analysis of the circle of Willis, especially the communicating arteries, was performed double-blind by two groups of two radiologists. Three types of arteries were identified: high flow or cross-cerebral circulation, patent and nonvisualised arteries. Cerebral angiography was the standard for comparison between the two methods. MRA did not reveal any arteries invisible on angiography, thus providing a specificity of 100%. The sensitivity of MRA was 89.2% for the anterior and 81.3% for the posterior communicating arteries, and 100% for the anterior, middle and posterior cerebral arteries. MRA was shown to be a useful technique for the assessment of patency of the circle of Willis. 相似文献
994.
Life satisfaction in patients with chest pain subsequently diagnosed as coronary heart disease – connection through depressive symptoms? 总被引:3,自引:0,他引:3
Valkamo M. Koivumaa-Honkanen H.-T. Hintikka J. Niskanen L. Honkalampi K. Viinamäki H. 《Quality of life research》2003,12(8):1099-1105
The aim of this study was to investigate factors associated with life dissatisfaction in symptomatic patients (n = 144) with chest pain subsequently diagnosed as coronary heart disease (CHD) by coronary angiography. Life dissatisfaction was assessed with a four-item life satisfaction scale (LS), depression with the 21-item Beck Depression Inventory (BDI) and other psychiatric symptoms with the symptom check list (SCL). DSM-III-R Axis I and Axis II psychiatric diagnoses were performed by means of the Structured Clinical Interview. All assessments took place one day before angiography. Twenty-four per cent of CHD patients were dissatisfied with their lives. Life dissatisfaction was associated with being unmarried. Dissatisfied patients had Axis I mental disorders and Axis II personality disorders more frequently than others. Psychiatric and depressive symptoms according to the SCL and BDI, respectively, were also higher among dissatisfied patients. In multiple logistic regression analyses, mental disorders were related to life dissatisfaction when age, sex, employment status, New York Heart Association class, duration of chest pain symptoms and work load were controlled in the model. Married subjects had a lower probability of being dissatisfied with their lives than other subjects (Odds Ratio, OR: 0.23). When BDI scores were included in the model, the only factor independently associated with life dissatisfaction was the severity of depressive symptoms (OR: 1.81). To conclude, life dissatisfaction is not primarily determined by the severity of CHD but by the existence of depressive symptoms. 相似文献
995.
作者选择乙基纤维素、聚乙烯醇等高分子材料制成涂膜剂,用大鼠皮进行双氯灭痛药膜的体外透皮速率测定。结果表明,氮酮与丙二醇可以促进药物渗透。不同的高分子材料可影响药物的扩散与释放,从而影响其透皮速率。与无膜无促透剂处方相比,药物在乙基纤维素中的透皮速率没有增加,在聚乙烯醇膜中的透皮速率有显著增加。 相似文献
996.
Tess Cramond 《ANZ journal of surgery》1997,67(8):512-519
John Coakley Lettsom (1744–1815) founded the Medical Society of London and played a key role in the development of the Royal Humane Society. His Quaker background underpinned his interest in social reform. He established dispensaries and soup kitchens for the poor, recognized the need for public health measures in the control of disease, and advocated prison reform and education of the poor. 相似文献
997.
无张力疝修补术后顽固性疼痛原因和对策 总被引:1,自引:0,他引:1
目的 探讨无张力疝修补术后的顽固性疼痛病因及预防治疗。方法 将同期无张力疝修补术与传统的腹股沟疝修补方法进行比较。结果 无张力疝修补术后的顽固性疼痛率为9.02%(12/133),传统的腹股沟疝修补方法疼痛率为8.61%(18/209)。无张力疝修补与传统的腹股沟疝修补相比,术后顽固性疼痛的发生率差异无显著性(P>0.05)。结论 无张力疝修补并不一定减少传统的腹股沟疝修补术后顽固性疼痛,手术规范操作是预防的关键,治疗应先保守治疗,无效再考虑手术治疗。 相似文献
998.
大肠癌误诊误治较为普通。从总结经验教训出发,本文对确诊前曾发生过误诊误治的536例大肠癌进行详尽的分析。本组病例536例,曾719次先后被误诊为32种疾病,其中误诊为“痔”“痢疾”“肠炎”“肠梗阻”等最为常见,误诊为其它疾病也时有发生,严重的影响其预后。在误诊原因上,除病人自误外,与医生责任心不强,询问病史不细,本行或未认真行有关检查,特别是直肠指诊检查和结肠内窥镜检查是分不开的。文章就今后如何减少误诊,提高早期诊断率,提出了5点措施,强调了直肠指诊和结肠内窥镜检查的重要价值。 相似文献
999.
A群脑膜炎多糖菌苗接种前后流脑流行规律的改变及今后预防对策 总被引:1,自引:0,他引:1
Wu Gueikuens et al. Collaboration of Provincial Sanitary Anti-epidemic Station Institute of Epidemiology Microbiology 《中国公共卫生学报》1994,13(5):263-264
本文研究了在使用菌苗预防前后的流行性脑脊髓膜炎流行强度的变迁,年龄、地区及季节分布特点,人群的易感性及带菌率之间的关系,并讨论了今后的预防措施。 相似文献
1000.
本文报道pH指示剂吸收度比值法测定盐酸乙胺丁醇的含量。该法采用指示剂为0.05%茜素黄R,测定波长374nm和500nm;标准液为0.1mol/L NaOH;仪器为WFZ-800D_2型分光光度计。测得三批盐酸乙胺丁醇的含量分别为99.5±0.04%,99.4±0.05%和99.6±0.03%.同时与药典法比较,结果一致。 相似文献