全文获取类型
收费全文 | 3734篇 |
免费 | 155篇 |
国内免费 | 64篇 |
专业分类
耳鼻咽喉 | 43篇 |
儿科学 | 61篇 |
妇产科学 | 61篇 |
基础医学 | 378篇 |
口腔科学 | 107篇 |
临床医学 | 356篇 |
内科学 | 533篇 |
皮肤病学 | 52篇 |
神经病学 | 278篇 |
特种医学 | 107篇 |
外科学 | 531篇 |
综合类 | 429篇 |
预防医学 | 347篇 |
眼科学 | 92篇 |
药学 | 340篇 |
中国医学 | 85篇 |
肿瘤学 | 153篇 |
出版年
2024年 | 8篇 |
2023年 | 67篇 |
2022年 | 167篇 |
2021年 | 176篇 |
2020年 | 139篇 |
2019年 | 155篇 |
2018年 | 158篇 |
2017年 | 98篇 |
2016年 | 151篇 |
2015年 | 109篇 |
2014年 | 304篇 |
2013年 | 251篇 |
2012年 | 219篇 |
2011年 | 226篇 |
2010年 | 149篇 |
2009年 | 174篇 |
2008年 | 176篇 |
2007年 | 150篇 |
2006年 | 172篇 |
2005年 | 129篇 |
2004年 | 99篇 |
2003年 | 84篇 |
2002年 | 70篇 |
2001年 | 67篇 |
2000年 | 46篇 |
1999年 | 56篇 |
1998年 | 33篇 |
1997年 | 26篇 |
1996年 | 26篇 |
1995年 | 26篇 |
1994年 | 29篇 |
1993年 | 20篇 |
1992年 | 16篇 |
1991年 | 19篇 |
1990年 | 20篇 |
1989年 | 16篇 |
1988年 | 17篇 |
1987年 | 15篇 |
1986年 | 7篇 |
1985年 | 14篇 |
1984年 | 10篇 |
1983年 | 4篇 |
1982年 | 8篇 |
1981年 | 13篇 |
1980年 | 5篇 |
1978年 | 7篇 |
1977年 | 5篇 |
1972年 | 3篇 |
1971年 | 2篇 |
1969年 | 2篇 |
排序方式: 共有3953条查询结果,搜索用时 15 毫秒
71.
The purpose of this study was to test the usefulness of some morphometric parameters of the teeth in 5 different age groups through images of Cone Beam CT. 118 upper central incisors clinically acquired of 60 women and 58 men aged between 22 and 70 years were selected. The hard tissue volume and the pulp cavity volume of each tooth was obtained and computed by the software DentalSlice® and the measures were assessed (pulp cavity volume, hard tissue volume, tooth volume and pulp cavity/tooth volume ratio). The pulp cavity volume and the pulp cavity/tooth volume ratio showed significant differences between age groups (p < 0.001). Linear regression analysis showed a coefficient of determination of 0.21 which suggests that there is a weak correlation between the pulp cavity/tooth volume ratio and age. 相似文献
72.
目的:了解北京市二级医院护理人员专业自主性现状,并分析其影响因素。方法于2014年1—3月以中文版护理实践量表( NAS)为调查工具,对北京市平谷区3家二级医院364名临床科室护理人员的专业自主性进行调查。结果3家二级医院的364名护理人员专业自主性得分为(177.96±18.52)分,处于中高等水平。不同年龄、护龄、职称、职务的护理人员的专业自主性得分比较差异有统计学意义(t值分别为6.284,9.700,5.410,6.435;P<0.05)。结论管理者应关注自主性较低人群,有针对性的采取措施,提高护理人员整体的专业自主性水平,以提升护理质量。 相似文献
73.
Background
The federal and provincial governments in Canada have invested an enormous amount of resources to measure, report and reduce surgical wait times. Yet these measures under-report the wait period that patients’ actually experience, because they do not capture the length of time a patient spends waiting to see the surgeon for a surgical assessment. This unmeasured time is referred to as the “wait one” (W1). Little is known about W1 and the effects that this has on patients’ health. Similarly, it is not understood whether patients waiting for surgical assessment actually want or need surgery. Existing administrative and clinical dataset do not capture information on health and decision-making while the patient is waiting for care form a specialist. The objective of this proposed study is to understand the impact that W1 for elective surgeries has on the health of patients and to determine whether this time can be reduced.Methods/Design
A prospective survey design will be used to measure the health of patients waiting for surgical assessment. Working with the support of the surgical specialities in Vancouver Coastal Health, we will survey patients immediately after being referred for surgical assessment, and every four months thereafter, until they are seen by the surgeon.Validated survey instruments will be used, including: generic and condition-specific health status questionnaires, pain and depression assessments. Other factors that will be measured include: patients’ knowledge about their condition, and their desired autonomy in the decision making process. We have piloted data collection in one surgical specialty in order to demonstrate feasibility.Discussion
The results from this study will be used to quantify changes in patients’ health while they wait for surgical assessment. Based on this, policy- and decision-makers could design care interventions during W1, aimed at mitigating any negative health consequences associated with waiting. The results from this study will also be used to better understand whether there are factors that predict patients’ desire to proceed to surgery. These could be used to guide future research into experimenting with interventions to minimize inappropriate referrals and where they are best targeted. 相似文献74.
75.
Toiyama Y Araki T Yoshiyama S Miki C Kusunoki M 《World journal of gastroenterology : WJG》2005,11(43):6888-6890
We report a case of secondary pouchitis, defined as a mucosal inflammatory lesion in the ileal reservoir provoked by pouch-related complication following total colectomy and pouch anal anastomosis, which was successfully treated by salvage surgery- A 20-year-old woman with ulcerative colitis developed acute severe bloody diarrhea following proctocolectomy, ileal pouch-anal anastomosis and diverting ileostomy. She was diagnosed as having a secondary pouchitis mainly caused by a peripouch abscess and partly concerned with the abnormal pouch formation. The remnant rectum and ileal pouch were excised and ileal pouch-anal anastomosis and diverting ileostomy were constructed. The postoperative course was uneventful with no sign of pouchitis. Salvage surgery may be indicated to treat secondary pouchitis when caused by surgery-related complications. 相似文献
76.
77.
Inflammatory bowel diseases(IBD), conventionally consist of Crohn's disease(CD) and ulcerative colitis. They occur in individuals with high risk genotype for the disease in the setting of appropriate environmental factors. The pathogenesis of IBD involves a dysregulated autoimmune response to gut dysbiosis, which in turn is triggered due to exposure to various inciting environmental factors. But there is no clearly defined etiology of IBD and this type of disease is termed as "idiopathic IBD", "classic IBD", or "primary IBD". We reviewed the current medical literature and found that certain etiological factors may be responsible for the development of IBD or IBD-like conditions, and we consider this form of de novo IBD as "secondary IBD". Currently known factors that are potentially responsible for giving rise to secondary IBD are medications; bowel altering surgeries and transplantation of organs, stem cells or fecal microbiome. Medications associated with the development of secondary IBD include; immunomodulators, anti-tumor necrosis factor alpha agents, anti-interleukin agents, interferons, immune stimulating agents and checkpoint inhibitors. Colectomy can in some cases give rise to de novo CD, pouchitis of the ileal pouch, or postcolectomy enteritis syndrome. After solid organ transplantation or hematopoietic stem cell transplantation, the recipient may develop de novo IBD or IBD flare. Fecal microbiota transplantation has been widely used to treat patients suffering from recurrent Clostridium difficile infection but can also causes IBD flares. 相似文献
78.
背景 利妥昔单克隆抗体(RTX)用于肾小球疾病的治疗已近20年,近年来其在治疗原发性和继发性肾病方面积累了一些循证医学证据,但对于较为明显的肾功能不全患者是否适合应用RTX进行挽救性治疗,目前尚无相关研究。目的 观察RTX挽救性治疗继发性难治性肾病患者的有效性和安全性。方法 回顾性选取2018-2019年北京大学国际医院收治的所有住院使用RTX治疗的成年难治性肾病患者48例。根据原发病诊断结果将患者分为原发性肾病(PN)组和继发性肾病(SN)组,再将SN组依据RTX治疗前血肌酐(Scr)分为SN-NST亚组(Scr<300 μmol/L)和SN-ST亚组(Scr≥300 μmol/L)。收集所有患者的一般资料(包括性别、年龄、体质量、身高、体表面积、原发病),RTX治疗前、后实验室检查结果〔24 h尿蛋白(Upro)、白细胞计数(WBC)、红细胞计数(RBC)、血小板计数(PLT)、白蛋白(Alb)、Scr、CD4+细胞计数〕,计算CD4+细胞计数/WBC比例,记录RTX治疗期间严重不良事件〔包括严重感染全身(应用抗生素≥7 d或联合应用2种及以上抗感染药物)、肾脏替代治疗(RRT)、多脏器功能衰竭综合征(MODS)、死亡等〕,RTX末次治疗后3个月肾脏转归情况(即是否行维持性血液透析)。结果 48例使用RTX治疗的难治性肾病患者均进行肾穿刺活检;PN组19例(39.6%),SN-NST亚组14例(29.2%),SN-ST亚组15例(31.2%)。SN-ST亚组患者年龄小于PN组和SN-NST亚组(P<0.05)。PN组患者RTX治疗前24 hUpro、RBC、PLT高于SN-NST亚组、SN-ST亚组,Alb低于SN-NST亚组、SN-ST亚组(P<0.05);SN-ST亚组患者RTX治疗前Scr高于PN组、SN-NST亚组,CD4+细胞计数低于PN组、SN-NST亚组(P<0.05)。SN-ST亚组患者RTX治疗后Scr高于PN组、SN-NST亚组(P<0.05)。PN组、SN-NST亚组患者RTX治疗后24 hUpro较同组治疗前降低(P<0.05)。SN-NST亚组、SN-ST亚组患者RTX治疗后WBC较同组治疗前降低(P<0.05)。SN-ST亚组患者RTX治疗后RBC较同组治疗前升高(P<0.05)。PN组患者RTX治疗后PLT较同组治疗前降低,SN-ST亚组患者RTX治疗后PLT较同组治疗前升高(P<0.05)。PN组、SN-NST亚组患者RTX治疗后Alb较同组治疗前升高(P<0.05)。三组患者RTX单位时间体表面积的累积剂量比较〔PN组、SN-NST亚组、SN-ST亚组依次为(437±322)、(503±344)、(331±312)mg?月-1?(m2)-1〕,差异无统计学意义(F=1.048,P=0.359)。SN-ST亚组患者RTX治疗期间严重感染发生率、行RRT者比例及RTX末次治疗后3个月行维持性血液透析者比例高于PN组(P<0.05);SN-ST亚组患者RTX治疗期间行RRT者比例、RTX末次治疗后3个月行维持性血液透析者比例高于SN-NST亚组(P<0.05)。结论 Scr≥300 μmol/L的继发性难治性肾病患者应用RTX治疗对其肾病改善作用不明显,且会明显增加其严重感染和肾衰竭发生风险,故RTX不应作为这部分患者的挽救治疗措施。 相似文献
79.
80.
《岭南心血管病杂志(英文版)》2014,(3)
The direct-acting platelet P2Y12 receptor antagonist ticagrelor can reduce the incidence of major adverse cardiovascular events when administered at hospital admission to patients with ST-segment elevation myocardial infarction(STEMI). Whether prehospital administration of ticagrelor can improve coronary reperfusion and the clinical outcome is unknown. Methods We conducted an international, multicenter, randomized, doubleblind study involving 1862 patients with ongoing STEMI of less than 6 hours' duration, comparing prehospital(in the ambulance) versus in-hospital(in the catheterization laboratory) treatment with ticagrelor. The coprimary end points were the proportion of patients who did not have a 70% or greater resolution of ST-segment elevation before percutaneous coronary intervention(PCI) and the proportion of patients who did not have Thrombolysis in Myocardial Infarction flow grade 3 in the infarct-related artery at initial angiography.Secondary end points included the rates of major adverse cardiovascular events and definite stent thrombosis at30 days. Results The median time from randomization to angiography was 48 minutes, and the median time difference between the two treatment strategies was 31 minutes. The two coprimary end points did not differsignificantly between the prehospital and in-hospital groups. The absence of ST-segment elevation resolution of 70% or greater after PCI(a secondary end point) was reported for 42.5% and 47.5% of the patients, respectively. The rates of major adverse cardiovascular events did not differ significantly between the two study groups. The rates of definite stent thrombosis were lower in the prehospital group than in the in-hospital group(0% vs. 0.8% in the first 24 hours; 0.2% vs. 1.2% at 30 days). Rates of major bleeding events were low and virtually identical in the two groups, regardless of the bleeding definition used. Conclusions Prehospital administration of ticagrelor in patients with acute STEMI appeared to be safe but did not improve pre-PCI coronary reperfusion. 相似文献