全文获取类型
收费全文 | 32484篇 |
免费 | 7466篇 |
国内免费 | 587篇 |
专业分类
耳鼻咽喉 | 534篇 |
儿科学 | 850篇 |
妇产科学 | 635篇 |
基础医学 | 2108篇 |
口腔科学 | 1756篇 |
临床医学 | 7777篇 |
内科学 | 6874篇 |
皮肤病学 | 819篇 |
神经病学 | 3184篇 |
特种医学 | 1060篇 |
外国民族医学 | 4篇 |
外科学 | 3818篇 |
综合类 | 1820篇 |
现状与发展 | 2篇 |
一般理论 | 2篇 |
预防医学 | 3666篇 |
眼科学 | 834篇 |
药学 | 1633篇 |
29篇 | |
中国医学 | 623篇 |
肿瘤学 | 2509篇 |
出版年
2024年 | 170篇 |
2023年 | 1461篇 |
2022年 | 584篇 |
2021年 | 1293篇 |
2020年 | 1580篇 |
2019年 | 921篇 |
2018年 | 2094篇 |
2017年 | 2120篇 |
2016年 | 2060篇 |
2015年 | 2285篇 |
2014年 | 2610篇 |
2013年 | 2666篇 |
2012年 | 1828篇 |
2011年 | 1914篇 |
2010年 | 1835篇 |
2009年 | 1977篇 |
2008年 | 1354篇 |
2007年 | 1206篇 |
2006年 | 1207篇 |
2005年 | 1042篇 |
2004年 | 865篇 |
2003年 | 843篇 |
2002年 | 759篇 |
2001年 | 772篇 |
2000年 | 672篇 |
1999年 | 669篇 |
1998年 | 415篇 |
1997年 | 413篇 |
1996年 | 396篇 |
1995年 | 356篇 |
1994年 | 218篇 |
1993年 | 204篇 |
1992年 | 256篇 |
1991年 | 207篇 |
1990年 | 168篇 |
1989年 | 197篇 |
1988年 | 157篇 |
1987年 | 125篇 |
1986年 | 109篇 |
1985年 | 96篇 |
1984年 | 72篇 |
1983年 | 46篇 |
1982年 | 35篇 |
1981年 | 27篇 |
1980年 | 26篇 |
1979年 | 22篇 |
1978年 | 21篇 |
1977年 | 22篇 |
1976年 | 16篇 |
1971年 | 17篇 |
排序方式: 共有10000条查询结果,搜索用时 250 毫秒
91.
Jin H. Han MD MSc Karen F. Miller RN MPA Alan B. Storrow MD 《Academic emergency medicine》2007,14(3):228-233
Background: Elder patients with acute coronary syndromes (ACS) are less likely to receive cardiac catheterization. The reasons for this are unclear.
Objectives: To assess whether elder patients who had a documented history of dementia, lived in extended care facilities, or had do not intubate–do not resuscitate (DNR-DNI) advance directives were less likely to receive cardiac catheterization, despite having ACS with high-risk features.
Methods: This was a medical record review conducted at an urban teaching hospital. DNR-DNI status before hospitalization, extended care facility (nursing home or assisted living) residence, and a previous diagnosis of dementia were obtained from the medical record. Patients 65 years and older who presented to the emergency department with acute myocardial infarction or with unstable angina with ST segment deviation were included. Univariate and multivariate logistic regression were performed, and odds ratios (ORs) were reported with their 95% confidence intervals (CIs).
Results: Of the 201 eligible patients, 66 (32.8%) patients did not undergo cardiac catheterization. In the univariate analysis, patients who had dementia, resided in extended care facilities, or were DNR-DNI were less likely to receive cardiac catheterization. Only extended care facility residence (OR, 0.18; 95% CI = 0.04 to 0.83) and DNR-DNI status (OR, 0.19; 95% CI = 0.04 to 0.92) remained significantly associated with decreased cardiac catheterization in the multivariate analysis.
Conclusions: Elder patients with ACS residing in extended care facilities or who are DNR-DNI are less likely to receive cardiac catheterization. Future studies concerning the quality of ACS care for elders should take these variables into account. 相似文献
Objectives: To assess whether elder patients who had a documented history of dementia, lived in extended care facilities, or had do not intubate–do not resuscitate (DNR-DNI) advance directives were less likely to receive cardiac catheterization, despite having ACS with high-risk features.
Methods: This was a medical record review conducted at an urban teaching hospital. DNR-DNI status before hospitalization, extended care facility (nursing home or assisted living) residence, and a previous diagnosis of dementia were obtained from the medical record. Patients 65 years and older who presented to the emergency department with acute myocardial infarction or with unstable angina with ST segment deviation were included. Univariate and multivariate logistic regression were performed, and odds ratios (ORs) were reported with their 95% confidence intervals (CIs).
Results: Of the 201 eligible patients, 66 (32.8%) patients did not undergo cardiac catheterization. In the univariate analysis, patients who had dementia, resided in extended care facilities, or were DNR-DNI were less likely to receive cardiac catheterization. Only extended care facility residence (OR, 0.18; 95% CI = 0.04 to 0.83) and DNR-DNI status (OR, 0.19; 95% CI = 0.04 to 0.92) remained significantly associated with decreased cardiac catheterization in the multivariate analysis.
Conclusions: Elder patients with ACS residing in extended care facilities or who are DNR-DNI are less likely to receive cardiac catheterization. Future studies concerning the quality of ACS care for elders should take these variables into account. 相似文献
92.
耳源性脑疝25例,抢救成功者19例。采用单纯脑脓肿穿刺抽脓抢救脑疝6例,仅1例成功;开颅减压术抢救脑疝20例,18例抢救成功。本组临床实践和文献报道都说明耳源性脑疝一旦发生应即刻行开颅减压术,能卓有成效地抢救生命 相似文献
93.
吡酮酸类抗菌药物的研究Ⅷ.1-对氟苯基-6-氟-1,4-二氢-4-氧-7-(1-哌嗪)噌啉-3-羧酸及其类似物的合成和构效关系 总被引:1,自引:0,他引:1
为探讨构效关系,合成了1-对氟苯基-6-氟-1,4-二氢-4-氧-7-(1-哌嗪)噌啉-3-羧酸及其喹啉、萘啶、吡啶[2,3-C]哒嗪环系类似物16个。测定了对大肠杆菌的MIC。用Hückel分子轨道理论(HMO)方法计算了四个母体环上电子密度。结果表明:环中氮的位置对药效团——3位羧基和4位羰基氧原子上电子密度的影响较大而影响其抗菌活性。喹啉、萘啶两环系的3位羧基和4位羰基氧原子上的电子密度较高,其体外抗菌活性较高;而噌啉及吡啶[2,3-C]哒嗪两环系的电子密度较低,其体外抗菌活性较低甚至消失。 相似文献
94.
异位妊娠259例临床总结分析 总被引:2,自引:0,他引:2
成丽虹 《国际医药卫生导报》2005,(17):71-72
目的探讨异位妊娠的发病相关因素,提出防治措施。方法对我院10年间收治的259例异位妊娠病例的发病趋势,既往病史及节育状况、误诊情况作一回顾分析。结果近10年异位妊娠发生率为2.19%并呈上升趋势。人工流产、节育手术、下腹部手术等与异位妊娠的发生关系密切。结论降低人工流产率,减少性病传播是预防异位妊娠发生的重要手段,随着高科技手段的应用使异位妊娠早期准确的诊断成为可能,为保守治疗赢得机会。 相似文献
95.
96.
Philip Peng FRCPC Manon Choiniere PhD Dominique Dion MD MSc Howard Intrater FRCPC Sandra LeFort PhD Mary Lynch FRCPC May Ong FRCPC Saifee Rashiq MSc DA FRCPC Gregg Tkachuk PhD Yves Veillette FRCPC 《Journal canadien d'anesthésie》2007,54(12):977-984
PURPOSE: The objective of this survey was to examine the services offered by multidisciplinary pain treatment facilities (MPTFs) across Canada and to compare access to care at these MPTFs. METHODS: A MPTF was defined as a clinic that advertised specialized multidisciplinary services for the diagnosis and management of patients with chronic pain, having a minimum of three different health care disciplines (including at least one medical speciality) available and integrated within the facility. The search method included approaching all hospital and rehabilitation centre administrators in Canada, the Insurance Bureau of Canada, the Workplace Safety and Insurance Board or similar body in each province. Designated investigators were responsible for confirming and supplementing MPTFs from the preliminary list for each province. Administrative leads at each eligible MPTF were asked to complete a detailed questionnaire regarding their MPTF infrastructure, clinical, research, teaching and administrative activities. RESULTS: Completed survey forms were received from 102 MPTFs (response rate 85%) with 80% concentrated in major cities, and none in Prince Edward Island and the Territories. The MPTFs offer a wide variety of treatments including non-pharmacological modalities such as interventional, physical and psychological therapy. The median wait time for a first appointment in public MPTFs is six months, which is approximately 12 times longer than non-public MPTFs. Eighteen pain fellowship programs exist in Canadian MPTFs and 64% engage in some form of research activities CONCLUSION: Canadian MPTFs are unable to meet clinical demands of patients suffering from chronic pain, both in terms of regional accessibility and reasonable wait time for patients' first appointment. 相似文献
97.
98.
99.
目的:分离培养小鼠骨髓间充质干细胞,研究其体外培养的生物特性。方法:获取骨髓间充质干细胞进行培养,倒置相差显微镜观察细胞生长情况。绘制生长曲线,冷冻保存细胞复苏后的生长状况观察。免疫细胞化学法鉴定细胞表面抗原。在地塞米松、β-甘油磷酸钠、抗坏血酸的作用下,进行成骨诱导分化。结果:原代和传代培养的细胞体外培养细胞呈现梭形、多角形外观,具有较强的生长增殖能力,复苏细胞生长状况无明显改变;细胞CD44。CD54抗原有阳性表达,CD34呈阴性表达。分化细胞表现成骨细胞特性,合成碱性磷酸酶(ALP)能力增强,矿化结节逐渐出现。结论:建立稳定可靠的分离培养小鼠骨髓MSCs方法,分离出的MSCs具有干细胞的生物特性,可用于骨组织工程中的种子细胞。 相似文献
100.
目的目前,对中国人抑郁体验的现象学理解很大程度上依赖于西方教科书和国际诊断系统中的描述。而临床经验告诉我们,不同地区、不同文化对情绪痛苦的表达有着各自的特点;但中国在这方面还缺乏研究。为此,我们采用民俗学方法对广州地区就诊人群的抑郁体验进行了研究。方法在广州市精神卫生中心门诊,采用定额取样招募40例有抑郁情绪的患者;问及的合适的病人共43人,只有3人不同意参加。采用开放式深入民俗学访谈了解患者的抑郁体验,即让患者用他们自己的话来讲述患病经历。对访谈进行录音,转录为文字并译成英文。对中英文记录分别进行了内容分析。结果除了西方教科书和诊断系统中描述的抑郁症状外,还发现了六个情感体验的类别:本地情感语汇、具身的情绪体验、隐含的忧伤、难以言状的痛苦、情绪不良造成的人际不和谐,以及专注于失眠。结论精神病学教科书和诊断系统中的描述未能涵盖中国抑郁患者对抑郁症状的全部体验。需要进一步研究抑郁体验与生活事件的关联及其在不同文化下的表现方式,这样才能作出与文化相适应的有效诊断。 相似文献