全文获取类型
收费全文 | 629篇 |
免费 | 43篇 |
国内免费 | 18篇 |
专业分类
耳鼻咽喉 | 7篇 |
儿科学 | 13篇 |
妇产科学 | 3篇 |
基础医学 | 91篇 |
口腔科学 | 12篇 |
临床医学 | 85篇 |
内科学 | 153篇 |
皮肤病学 | 1篇 |
神经病学 | 40篇 |
特种医学 | 64篇 |
外科学 | 64篇 |
综合类 | 9篇 |
预防医学 | 39篇 |
眼科学 | 7篇 |
药学 | 69篇 |
肿瘤学 | 33篇 |
出版年
2023年 | 7篇 |
2022年 | 6篇 |
2021年 | 6篇 |
2020年 | 4篇 |
2019年 | 18篇 |
2018年 | 15篇 |
2017年 | 19篇 |
2016年 | 9篇 |
2015年 | 12篇 |
2014年 | 15篇 |
2013年 | 33篇 |
2012年 | 20篇 |
2011年 | 37篇 |
2010年 | 24篇 |
2009年 | 13篇 |
2008年 | 23篇 |
2007年 | 27篇 |
2006年 | 28篇 |
2005年 | 18篇 |
2004年 | 17篇 |
2003年 | 15篇 |
2002年 | 7篇 |
2001年 | 9篇 |
2000年 | 16篇 |
1999年 | 27篇 |
1998年 | 23篇 |
1997年 | 16篇 |
1996年 | 26篇 |
1995年 | 12篇 |
1994年 | 15篇 |
1993年 | 20篇 |
1992年 | 12篇 |
1991年 | 13篇 |
1990年 | 11篇 |
1989年 | 18篇 |
1988年 | 17篇 |
1987年 | 13篇 |
1986年 | 5篇 |
1985年 | 7篇 |
1984年 | 4篇 |
1983年 | 6篇 |
1982年 | 9篇 |
1981年 | 5篇 |
1979年 | 3篇 |
1978年 | 3篇 |
1977年 | 4篇 |
1975年 | 5篇 |
1971年 | 4篇 |
1970年 | 3篇 |
1969年 | 3篇 |
排序方式: 共有690条查询结果,搜索用时 0 毫秒
11.
S Bydder NA Spry DRH Christie D Roos BH Burmeister H Krawitz S Davis DJ Joseph M Poulsen M Berry 《Journal of Medical Imaging and Radiation Oncology》2003,47(3):284-288
The purpose of this study was to prospectively examine the effectiveness and tolerability of a simple radiotherapy technique for the palliation of symptomatic liver metastases. Twenty‐eight patients with symptomatic liver metastases were enrolled from seven centres, and received targeted (partial or whole) liver irradiation consisting of 10 Gy in two fractions over 2 days. Symptoms at baseline were hepatic pain (27 patients), abdominal distension (19), night sweats (12), nausea (18) and vomiting (eight). Twenty‐two patients (76%) had failed previous treatment with chemotherapy, hormonal therapy and/or high‐dose steroids. Symptoms and potential toxicities were prospectively assessed at the time of treatment, then 2, 6 and 10 weeks later. Individual symptom response rates were 53?66% at 2 weeks. Partial or complete global symptomatic responses were noted in 15 patients (54%) overall. The treatment was well tolerated with two patients (7%) experiencing grade 3 toxicity (one vomiting and one diarrhoea); however, four patients reported temporary worsening of pain shortly after treatment. This simple and well‐tolerated treatment achieves useful palliation. 相似文献
12.
Kaare Solheim Knut A. Evensen Bjørn Høivik Steinar Karlsen Arne R. Rosseland 《Scandinavian cardiovascular journal : SCJ》2013,47(1):61-64
AbstractTwo operated cases of aorto-caval fistula due to ruptured abdominal aneurysm are reported. This is a rare and real surgical emergency and is fatal without operation. The classical symptoms of high-output failure occurring simultaneously with the findings of an expansible abdominal mass with thrill and bruit should facilitate clinical diagnosis. 相似文献
13.
14.
In the human erythrocyte membrane phosphatidylcholine and sphingomyelin reside mainly in the outer leaflet, whereas the aminophospholipids, phosphatidylethanolamine and phosphatidylserine, are mainly found in the inner leaflet. Maintenance of phospholipid asymmetry has been assumed to involve interactions between the aminophospholipids and the membrane skeleton, in particular spectrin. To investigate whether spectrin contributes to maintaining the phospholipid transbilayer distribution and kinetics of redistribution, we studied erythrocytes from hereditary spherocytosis patients whose spectrin levels ranged from 34% to 82% of normal. The phospholipid composition and the accessibility of membrane phospholipids to hydrolysis by phospholipases were in the normal range. Spin-labeled phosphatidylserine and phosphatidylethanolamine analogues that had been introduced into the outer leaflet were rapidly transported at 37 degrees C to the inner leaflet, whereas the redistribution of spin-labeled phosphatidylcholine was slower. The kinetics of transbilayer movement of these spin-labeled phospholipid in all samples was in the normal range and was not affected by the level of spectrin. Although these erythrocyte membranes contained as little as 34% of the normal level of spectrin and were characterized by several physical abnormalities, the composition, distribution, and transbilayer kinetics of the phospholipids were found to be normal. We therefore conclude that spectrin plays, at best, only a minor role in maintaining the distribution of erythrocyte membrane phospholipid. 相似文献
15.
Styles LA; Schalkwijk CG; Aarsman AJ; Vichinsky EP; Lubin BH; Kuypers FA 《Blood》1996,87(6):2573-2578
Acute chest syndrome (ACS) is associated with significant morbidity and is the leading cause of death in patients with sickle cell disease (SCD). Recent reports suggest that bone marrow fat embolism can be detected in many cases of severe ACS. Secretory phospholipase A2 (sPLA2) is an important inflammatory mediator and liberates free fatty acids, which are felt to be responsible for the acute lung injury of the fat embolism syndrome. We measured SPLA2 levels in 35 SCD patients during 20 admissions for ACS, 10 admissions for vaso-occlusive crisis, and during 12 clinic visits when patients were at the steady state. Eleven non-SCD patients with pneumonia were also evaluated. To determine if there was a relationship between sPLA2 and the severity of ACS we correlated SPLA2 levels with the clinical course of the patient. In comparison with normal controls (mean = 3.1 +/- 1.1 ng/mL), the non- SCD patients with pneumonia (mean = 68.6 +/- 82.9 ng/mL) and all three SCD patient groups had an elevation of SPLA2 (steady state mean = 10.0 +/- 8.4 ng/mL; vaso-occlusive crisis mean = 23.7 +/- 40.5 ng/mL; ACS mean = 336 +/- 209 ng/mL). In patients with ACS sPLA2 levels were 100- fold greater than normal control values, 35 times greater than values in SCD patients at baseline, and five times greater than non-SCD patients with pneumonia. The degree of SPLA2 elevation in ACS correlated with three different measures of clinical severity and, in patients followed sequentially, the rise in SPLA2 coincided with the onset of ACS. The dramatic elevation of SPLA2 in patients with ACS but not in patients with vaso-occlusive crisis or non-SCD patients with pneumonia and the correlation between levels of SPLA2 and clinical severity suggest a role for SPLA2 in the diagnosis and, perhaps, in the pathophysiology of patients with ACS. 相似文献
16.
17.
18.
19.
Nylund A Plarre H Karlsen M Fridell F Ottem KF Bratland A Saether PA 《Archives of virology》2007,152(1):151-179
Summary. In the present study, 24 smolt production sites were screened for the presence of infectious salmon anaemia virus (ISAV) with
the help of a specific real-time RT PCR assay, and 22 of these sites had smolts that were positive. If these smolt production
sites are representative for the prevalence of ISAV in Norwegian smolts, then most marine production sites must be considered
to be positive for ISAV. In addition, 92 European ISAV isolates have been genotyped based on the hemagglutinin-esterase gene
(HE), and their distribution pattern was analysed. This pattern has been coupled to information about the origin of smolt,
eggs, and broodfish in those cases where it has been possible to obtain such information, and with information about ISAV
in neighbouring farms. The pattern suggests that an important transmission route for the ISAV could be that the salmon farming
industry in Norway is circulating some of the isolates in the production cycle, i.e. some sort of vertical or transgenerational
transmission may occur. It has also been shown that avirluent ISAV isolates are fairly common in Norwegian farmed salmon.
Based on this, it is hypothesized that the change from avirulent to virulent ISAV isolates is a stochastic event that is dependent
on the replication frequency of the virus and the time available for changes in a highly polymorphic region (HPR) of the HE
gene to occur. This, and the possibility that only avirluent ISAV isolates are vertically transmitted, may explain why ISA
most often occurs at marine sites and why no more than about 15 farms get ISA every year in Norway. 相似文献
20.
Serological markers of extracellular matrix remodeling predict transplant‐free survival in primary sclerosing cholangitis 下载免费PDF全文