全文获取类型
收费全文 | 1237143篇 |
免费 | 87421篇 |
国内免费 | 12434篇 |
专业分类
耳鼻咽喉 | 16682篇 |
儿科学 | 36805篇 |
妇产科学 | 29962篇 |
基础医学 | 168206篇 |
口腔科学 | 32392篇 |
临床医学 | 114890篇 |
内科学 | 223599篇 |
皮肤病学 | 26286篇 |
神经病学 | 87829篇 |
特种医学 | 49103篇 |
外国民族医学 | 269篇 |
外科学 | 179702篇 |
综合类 | 57256篇 |
现状与发展 | 50篇 |
一般理论 | 272篇 |
预防医学 | 88560篇 |
眼科学 | 28149篇 |
药学 | 103416篇 |
200篇 | |
中国医学 | 15404篇 |
肿瘤学 | 77966篇 |
出版年
2022年 | 9273篇 |
2021年 | 15231篇 |
2020年 | 11123篇 |
2019年 | 12369篇 |
2018年 | 16335篇 |
2017年 | 14058篇 |
2016年 | 14940篇 |
2015年 | 18983篇 |
2014年 | 24666篇 |
2013年 | 32004篇 |
2012年 | 44670篇 |
2011年 | 47464篇 |
2010年 | 30470篇 |
2009年 | 27434篇 |
2008年 | 40693篇 |
2007年 | 42348篇 |
2006年 | 42326篇 |
2005年 | 39198篇 |
2004年 | 35503篇 |
2003年 | 33992篇 |
2002年 | 31999篇 |
2001年 | 63379篇 |
2000年 | 64024篇 |
1999年 | 52876篇 |
1998年 | 13589篇 |
1997年 | 12089篇 |
1996年 | 11873篇 |
1995年 | 11096篇 |
1994年 | 9927篇 |
1993年 | 9224篇 |
1992年 | 38160篇 |
1991年 | 36571篇 |
1990年 | 36022篇 |
1989年 | 34502篇 |
1988年 | 31043篇 |
1987年 | 30161篇 |
1986年 | 28338篇 |
1985年 | 26542篇 |
1984年 | 19233篇 |
1983年 | 16153篇 |
1979年 | 17069篇 |
1978年 | 11419篇 |
1977年 | 10246篇 |
1975年 | 10079篇 |
1974年 | 11671篇 |
1973年 | 11300篇 |
1972年 | 10761篇 |
1971年 | 10100篇 |
1970年 | 9261篇 |
1969年 | 8942篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
目的 探讨数字减影血管造影(DSA)诊断与介入治疗在胃肠道动脉性出血中的应用价值.方法 回顾性总结78例消化道动脉性出血患者的DSA表现和动脉栓塞、药物灌注的治疗经验.结果 本组患者十二指肠溃疡15例,胃溃疡5例,胃癌2例,Dieulafoy病1例,血管畸形和发育不良9例,胃肠术后吻合口出血8例,肝胆疾患术后肝动脉破裂出血10例,Crohn病5例、肠道憩室出血6例、小肠炎或溃疡6例,小肠息肉3例,小肠中度恶性间质瘤1例,小肠高分化平滑肌肉瘤2例,直结肠癌5例.74%(58/78)的患者DSA造影阳性,造影剂外溢直接征象者33%(26/78),术后吻合口出血直接征象者83%(15/18).介入治疗的病例中动脉药物灌注15例,技术成功率60%(9/15),临床成功率40%(6/15);栓塞36例,技术成功率86%(31/36),临床成功率72%(26/36);介人治疗后再出血率16%(8/51),其中1例栓塞后再呕血经胃镜治疗无效死亡.DSA造影和介入治疗后手术者27例,造影与术后病理诊断的符合率为78%(21/27).随访时间2个月至3年,未发生胃肠道缺血坏死等并发症.结论 DSA对消化道动脉性出血的定位、定性有着重要价值,选择性动脉栓塞及药物灌注止血安全有效,有助于择期手术和并发症处理. 相似文献
83.
Four clinical trials of porcine islet transplantation have been reported, and there are verbal reports that clinical trials on much larger scales are continuing in centers in China and Russia. The four reported trials are briefly reviewed and, in the light of the present status of experimental islet xenotransplantation, consideration is given to whether such trials are currently justified. The Ethics Committee of the International Xenotransplantation Association has (1) emphasized the need for encouraging studies in non-human primates before clinical trials should be undertaken, (2) mandatory monitoring for the transfer of porcine microorganisms, and (3) careful regulation and oversight by recognized bodies. Other aspects of the topic, such as the need for informed consent, are briefly discussed. We conclude that, at the present time, more data documenting convincing efficacy, focused on clinically applicable immunosuppressive regimens, are needed to justify the initiation of closely monitored clinical trials. A clinical trial may then be justified even though the potential risk to the patients, and possibly for society, will not be zero. 相似文献
84.
85.
B Nkgudi K A Robertson J Volmink B M Mayosi 《Suid-Afrikaanse tydskrif vir geneeskunde》2006,96(3):206-208
OBJECTIVE: To determine whether under-reporting of rheumatic fever occurs at hospital, municipal, provincial and national levels of the South African health system. BACKGROUND: Information on the incidence of rheumatic fever (RF) and the prevalence of rheumatic heart disease (RHD) is required for the prevention of valvular heart disease in developing countries. In South Africa, RF was made a notifiable condition in 1989. It has recently been suggested that the reporting of RF cases may be incomplete, possibly because of underreporting by health care professionals and deficient administration of the disease notification system in South Africa. METHOD AND RESULTS: We assessed whether underreporting of RF cases occurs by comparing the numbers of RF cases reported per year at hospital, municipal, provincial and national levels from 1990 to 2004. There was a fall in the number of RF cases reported per year at national and provincial level over the 15 years of observation. A detailed analysis of the number of RF cases reported at hospital, municipal and provincial level for a 5-year period showed that more cases were diagnosed in one hospital (serving a smaller population) than were captured at municipal and provincial level (serving a larger population), suggesting underreporting by health care professionals. There were discrepancies in the number of cases reported at municipal, provincial and national level, suggesting poor administration of the notification system. CONCLUSION: There appears to be underreporting of RF cases by health care professionals, and poor administration of the RF notification system. Health care professionals need to be educated about the statutory requirement to notify all RF cases in South Africa. An effective national disease notification system is required. 相似文献
86.
87.
88.
89.
Willemijn A K M Windt Atsua Tahara Alex C A Kluppel Dick de Zeeuw Robert H Henning Richard P E van Dokkum 《Journal of the renin-angiotensin-aldosterone system》2006,7(4):217-224
INTRODUCTION: Vasopressin, mainly through the V1a-receptor, is thought to be a major player in the maintenance of hyperfiltration. Its inhibition could therefore lead to a decrease in progression of chronic renal failure. To this end, the effect of the vasopressin V1a-receptor-selective antagonist, YM218, was studied on proteinuria and focal glomerulosclerosis in early and late intervention after 5/6 nephrectomy in rats, and compared with an angiotensin-converting enzyme inhibitor (ACE-I). MATERIALS AND METHODS: After 5/6 nephrectomy, early intervention was performed between week 2 and 10 thereafter with the V1a-receptor-selective antagonist (VRA, 10 mg/kg/day, n=10), enalapril (ACE-I, 10 mg/kg/day, n=9), or vehicle (n=8). Late intervention was performed in another group between week 6 and 12 with VRA (10 mg/kg/day, n=7), lisinopril (ACE-I, 5 mg/kg/day, n=7), or vehicle (n=7). RESULTS: In early intervention, proteinuria and focal glomerulosclerosis were significantly decreased by VRA compared to vehicle (44+7% and 59+8% respectively). ACE-I significantly decreased proteinuria (67+7%) and a trend towards a decrease in focal glomerulosclerosis was observed (30+18%). In late intervention, VRA did not decrease proteinuria and focal glomerulosclerosis compared to vehicle (21+20% and 0%, respectively), ACE-I significantly lowered proteinuria (92+2%) and a focal glomerulosclerosis (69+1%) lowering trend was observed. CONCLUSION: These results indicate that VRA may protect against early progression of renal injury after 5/6 nephrectomy, whereas its effectiveness seems limited in established renal damage. 相似文献
90.
肾移植术后并发尿路上皮肿瘤的临床分析 总被引:8,自引:0,他引:8
目的 分析肾移植患者并发尿路上皮肿瘤的特点,探讨其诊治方法。方法 自1998~2003年肾移植患者1293例,术后发生尿路上皮恶性肿瘤21例(1.6%)。男4例,女17例。17例原发病为慢性问质性肾炎。发生尿路上皮肿瘤距肾移植6~62个月,平均26个月。其中膀胱癌6例,单侧肾盂或输尿管癌6例,单侧肾盂或输尿管、膀胱癌8例,双侧肾盂输尿管癌1例。10例上尿路肿瘤发生部位与移植肾同侧,4例发生于移植肾对侧。临床症状以无痛性肉服血尿和反复泌尿系感染为主。19例行手术治疗,术后所有患者免疫抑制剂用量减少1/3并辅以局部灌注化疗。结果 2例行姑息性治疗的晚期肿瘤患者分别于发现肿瘤5、8个月死亡。余19例现已随访2~5年。13例肿瘤复发,复发部位为膀胱或对侧原。肾、输尿管。所有患者在免疫抑制剂减量期间均未出现急性排斥。2例因切除移植肾恢复透析,17例肾功能正常。结论 慢性间质性。肾炎导致。肾功能衰竭的。肾移植患者和女性肾移植患者易发生移植后尿路上皮肿瘤;移植肾同侧上尿路较对侧好发肿瘤;对移植肾对侧为首发的上尿路发生肿瘤者可预防性行双侧上尿路根治性切除。 相似文献