全文获取类型
收费全文 | 34549篇 |
免费 | 2240篇 |
国内免费 | 210篇 |
专业分类
耳鼻咽喉 | 298篇 |
儿科学 | 684篇 |
妇产科学 | 553篇 |
基础医学 | 4550篇 |
口腔科学 | 1015篇 |
临床医学 | 3479篇 |
内科学 | 7554篇 |
皮肤病学 | 775篇 |
神经病学 | 3721篇 |
特种医学 | 2385篇 |
外国民族医学 | 1篇 |
外科学 | 5465篇 |
综合类 | 192篇 |
一般理论 | 18篇 |
预防医学 | 1318篇 |
眼科学 | 748篇 |
药学 | 1946篇 |
中国医学 | 35篇 |
肿瘤学 | 2262篇 |
出版年
2023年 | 318篇 |
2022年 | 668篇 |
2021年 | 1151篇 |
2020年 | 660篇 |
2019年 | 884篇 |
2018年 | 1062篇 |
2017年 | 882篇 |
2016年 | 1065篇 |
2015年 | 1208篇 |
2014年 | 1473篇 |
2013年 | 1718篇 |
2012年 | 2632篇 |
2011年 | 2580篇 |
2010年 | 1569篇 |
2009年 | 1496篇 |
2008年 | 2175篇 |
2007年 | 2254篇 |
2006年 | 1923篇 |
2005年 | 1869篇 |
2004年 | 1715篇 |
2003年 | 1591篇 |
2002年 | 1397篇 |
2001年 | 403篇 |
2000年 | 381篇 |
1999年 | 403篇 |
1998年 | 298篇 |
1997年 | 244篇 |
1996年 | 185篇 |
1995年 | 150篇 |
1994年 | 140篇 |
1993年 | 132篇 |
1992年 | 175篇 |
1991年 | 166篇 |
1990年 | 143篇 |
1989年 | 176篇 |
1988年 | 116篇 |
1987年 | 103篇 |
1986年 | 113篇 |
1985年 | 91篇 |
1984年 | 76篇 |
1983年 | 65篇 |
1982年 | 62篇 |
1980年 | 54篇 |
1979年 | 93篇 |
1978年 | 63篇 |
1977年 | 57篇 |
1974年 | 65篇 |
1973年 | 56篇 |
1972年 | 58篇 |
1971年 | 62篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
63.
Nikolaus A Haas Christoph K Camphausen 《Pediatric critical care medicine》2006,7(4):399; author reply 399-399; author reply 400
64.
Onnen Grauhan Henryk Siniawski Michael Dandel Hans Lehmkuhl Christoph Knosalla Miralem Pasic Yu-Guo Weng Roland Hetzer 《European journal of cardio-thoracic surgery》2007,32(4):634-638
OBJECTIVE: Due to the shortage of donor hearts, the criteria for organ acceptability have been considerably extended and donor grafts with coronary atherosclerosis are among those offered. This study evaluated whether and to what degree pre-existing coronary atherosclerosis may be acceptable. METHODS: A total of 1253 consecutive HTx recipients were investigated retrospectively for donor-transmitted coronary atherosclerosis (DCAS). Donor-transmitted coronary atherosclerosis was defined as focal atherosclerosis with stenosis of at least 50%. Inclusion criteria were absence of pre-HTx angiogram but performance of angiogram or autopsy within 6 months after heart transplantation. Kaplan-Meier analysis and log-rank test were used. RESULTS: Eighty-five out of 1253 (6.8%) cases were excluded, since coronary evaluation was not performed within 6 months (n=45) or hearts had undergone pre-transplant angiography (n=40). In 1086 patients no donor-transmitted coronary atherosclerosis was found (NDCAS group) and in 82 patients (7%) donor-transmitted coronary atherosclerosis was diagnosed by angiography (n=49) or autopsy (n=33). Single-vessel donor-transmitted coronary atherosclerosis was found in 53/82 patients (DCAS1 group) and double- or triple-vessel donor-transmitted coronary atherosclerosis in 26/82 patients (DCAS2/3 group). Three of the 82 patients with donor-transmitted coronary atherosclerosis were excluded since the autopsy report was unclear regarding degree of atherosclerosis. Early after heart transplantation the 30-day mortality in the NDCAS and DCAS1 groups was 12.2% versus 13.2% whereas in the DCAS2/3 group it was 61.5%. Beyond the first year the annual decrease with and without donor-transmitted coronary atherosclerosis (single-vessel disease) is comparable. CONCLUSIONS: Donor screening without coronary angiogram overlooks significant atherosclerotic lesions in a considerable number of cases (7.0%). Therefore, angiographic donor screening should be performed. Donor grafts with single-vessel coronary atherosclerosis may be accepted as marginal hearts; however, in our opinion, revascularisation (CABG, PTCA) should be considered. Grafts with two- or even three-vessel coronary atherosclerosis seem to have a serious risk for early graft failure. Beyond the first year the outcome of healthy grafts and grafts with donor-transmitted coronary atherosclerosis seems to be comparable. 相似文献
65.
Christian Etz Henryk Welp Hans H Scheld Christof Schmid 《European journal of cardio-thoracic surgery》2005,27(4):722-723
We report on an unusual case of a young female patient who received an implantable LVAD after unsuccessful emergency coronary bypass surgery following acute myocardial infarction. After LVAD placement, it became evident that the patient had been pregnant. She had to undergo gynaecological surgery during mechanical support to remove the deceased fetus. 相似文献
66.
Sergi Sastre Guillem Bori Sebastian Garcia Andreu Combalia 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2005,15(1):63-65
A rare case of an infected chronic hematoma in a patient with immunodeficiency syndrome mimicking a soft tissue neoplasm is presented. There are few reported cases of hematogenous infection of chronic hematomas, which be difficult to differentiate from soft tissue neoplasms. 相似文献
67.
68.
Thomas Müller Christoph Erdmann Siegfried Muhlack Dirk Bremen Horst Przuntek Dirk Woitalla 《Journal of clinical neuroscience》2007,14(5):424-428
BACKGROUND: A possible strategy to prolong plasma metabolism of Levodopa/Carbidopa (LD/CD) is Entacapone addition (EN), which improves impaired motor behaviour in patients with Parkinson's disease (PD). AIMS OF THE STUDY: Objectives were to evaluate the clinical response to an increased dopaminergic substitution with EN by clinical rating and assessment of complex motions and to investigate the change of movement in PD patients during repeat drug administration during an eight hour interval. METHODS: We used peg insertion with a computer based device and clinical rating for assessment of motor function in 20 treated PD patients. They received LD/CD and then the same LD/CD dosage plus EN in a standardised, open label fashion. RESULTS: Motor scores and performance of the instrumental task were significantly better and the fluctuation of movement was less intense during the LD/CD/EN condition according to the motor test outcomes. CONCLUSION: EN supplementation improves motor symptoms and provides a more continuous movement behaviour in PD patients. 相似文献
69.
Jürgen Treckmann Andreas Paul Georgios C. Sotiropoulos Hauke Lang Arzu Özcelik Fuat Saner Christoph E. Broelsch 《Journal of gastrointestinal surgery》2008,12(2):313-318
Introduction Delayed massive hemorrhage induced by pancreatic fistula after pancreaticoduodenectomy is a rare but life-threatening complication.
The purpose of this study was to analyze the clinical course of patients with late hemorrhage, with or without sentinel bleeding,
to better define treatment options in the future.
Material and Methods From April 1998 to December 2006, 189 pancreaticoduodenectomies were performed. Eleven patients, including two patients referred
from other hospitals, were treated with delayed massive hemorrhage occurring 5 days or more after pancreaticoduodenectomy.
Sentinel bleeding was defined as minor blood loss via surgical drains or the gastrointestinal tract with an asymptomatic interval
until development of hemorrhagic shock. The clinical data of patients with bleeding episodes were analyzed retrospectively.
Results Eight of the 11 patients had sentinel bleeding, and seven of them had it at least 6 h before acute deterioration. Seven out
of 11 patients died, five out of eight with sentinel bleeding. No differences could be detected between patients with or without
sentinel bleeding before delayed massive hemorrhage. The only difference found was that non-surviving patients were significantly
older than surviving patients. Delayed massive hemorrhage is a common cause of death after pancreaticoduodenostomy complicated
by pancreatic fistula formation. The observation of sentinel bleeding should lead to emergency angiography and dependent from
the result to emergency relaparotomy to increase the likelihood of survival. 相似文献
70.
Jennifer C. Chen Katrina L. Schmid Brian Brown Marion H. Edwards Bibianna SY Yu John KF Lew 《Clinical & experimental optometry》2003,86(5):323-330
Purpose: Caucasian children with myopia have elevated response accommodative vergence to accommodation (AC/A) ratios. The purpose of this study was twofold: to determine if response AC/A ratios vary with refractive error and with myopic progression rate in Hong Kong Chinese children, and to determine the effect of beta‐adrenergic antagonism with topical timolol application on AC/A ratios. Methods: Thirty children aged eight to 12 years participated in the study. All refractive errors were corrected with spectacle lenses. Accommodative responses were measured using a Shin‐Nippon autorefractor and concurrent changes in vergence were assessed using a vertical prism and a Howell‐Dwyer card at three metres and 0.33 metre. Accommodative demand was altered using plus or minus two dioptre lenses and lens‐ and distance‐induced response AC/A ratios were calculated. Measurements were repeated 30 minutes after the instillation of topical timolol maleate (0.5 per cent). Results: AC/A ratios appeared higher in progressing myopic children but the difference was not statistically significant. Timolol application reduced accommodative convergence (AC) in the stable myopes (reduction = ‐3 ± 1.14A) but not in the emmetropes (0.69 ± 0.9P) or progressing myopes (0.16 ± 0.43A) and this difference between refractive groups was statistically s ignificant (F2,27= 3.766; P= 0.036). However, timolol did not produce a significant change in the accommodative response to positive or negative lenses or response AC/A ratios. Conclusions: We did not find that AC/A ratios in myopic Chinese children were elevated and therefore, it is unlikely that elevated AC/A ratios are responsible for the high levels of myopia that occur in Hong Kong. The finding that timolol reduced AC in the stable myopes suggests that the autonomic control of accommodative convergence in these children may be different from that in emmetropic children and those with progressing myopia. 相似文献