全文获取类型
收费全文 | 895篇 |
免费 | 34篇 |
国内免费 | 65篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 59篇 |
妇产科学 | 12篇 |
基础医学 | 64篇 |
口腔科学 | 37篇 |
临床医学 | 135篇 |
内科学 | 220篇 |
皮肤病学 | 23篇 |
神经病学 | 8篇 |
特种医学 | 244篇 |
外科学 | 43篇 |
综合类 | 29篇 |
预防医学 | 24篇 |
眼科学 | 14篇 |
药学 | 46篇 |
肿瘤学 | 34篇 |
出版年
2021年 | 6篇 |
2020年 | 2篇 |
2019年 | 4篇 |
2018年 | 3篇 |
2017年 | 8篇 |
2016年 | 9篇 |
2015年 | 15篇 |
2014年 | 16篇 |
2013年 | 24篇 |
2012年 | 12篇 |
2011年 | 10篇 |
2010年 | 27篇 |
2009年 | 38篇 |
2008年 | 12篇 |
2007年 | 56篇 |
2006年 | 24篇 |
2005年 | 19篇 |
2004年 | 10篇 |
2003年 | 6篇 |
2002年 | 14篇 |
2001年 | 13篇 |
2000年 | 11篇 |
1999年 | 13篇 |
1998年 | 60篇 |
1997年 | 70篇 |
1996年 | 70篇 |
1995年 | 59篇 |
1994年 | 42篇 |
1993年 | 49篇 |
1992年 | 8篇 |
1991年 | 14篇 |
1990年 | 13篇 |
1989年 | 39篇 |
1988年 | 22篇 |
1987年 | 36篇 |
1986年 | 12篇 |
1985年 | 24篇 |
1984年 | 15篇 |
1983年 | 23篇 |
1982年 | 19篇 |
1981年 | 17篇 |
1980年 | 20篇 |
1979年 | 1篇 |
1978年 | 5篇 |
1977年 | 9篇 |
1976年 | 4篇 |
1975年 | 6篇 |
1966年 | 2篇 |
1948年 | 1篇 |
1947年 | 1篇 |
排序方式: 共有994条查询结果,搜索用时 8 毫秒
41.
Mewissen MW; Erickson SJ; Foley WD; Lipchik EO; Olson DL; McCann KM; Schreiber ER 《Radiology》1989,173(1):155-157
Color Doppler flow imaging or compression ultrasound (US) was used to prospectively determine frequency of thrombosis at 54 venous insertion sites (47 in common femoral veins, seven in right internal jugular veins) after percutaneous placement of Greenfield filters for interruption of the inferior vena cava. Fifty-one filters were successfully placed in 51 patients with a dilator set or a balloon angioplasty catheter. Nine focal thrombi were detected in the common femoral vein (19%) and one in the right internal jugular vein (14%). Use of dilators induced eight thrombi (24%), compared with two (10%) from balloon catheters. The left common femoral vein had a high frequency of thrombosis, regardless of dilation technique (five of nine). Of nine patients with acute common femoral vein thrombosis, four became symptomatic within 10 days after the procedure. Patients may remain asymptomatic or have delayed symptoms; thus, US is valuable for determining patients at risk of thrombosis of the common femoral vein. 相似文献
42.
HL Robbins M Hetzel S Mungall SJ Cawthorn 《Annals of the Royal College of Surgeons of England》2015,97(1):e1-e2
Tuberculous mastitis is rare, especially in Western countries. We describe a case where the interferon gamma release assay blood test led to diagnosis and successful treatment of the disease. 相似文献
43.
44.
von der Mohlen MA; van Deventer SJ; Levi M; van den Ende B; Wedel NI; Nelson BJ; Friedmann N; ten Cate JW 《Blood》1995,85(12):3437-3443
A recombinant endotoxin-neutralizing protein, rBPI23, was shown to partially prevent endotoxin-induced activation of the fibrinolytic and coagulation systems in experimental endotoxemia in humans. In a placebo- controlled, blinded crossover study, eight volunteers were challenged twice with an intravenous bolus injection of endotoxin (40 EU/kg of body weight) and concurrently received either rBPI23 (1 mg/kg) or placebo (human serum albumin, 0.2 mg/kg). rBPI23 treatment significantly lowered the endotoxin-induced fibrinolytic response, ie, reduced the release of tissue-type plasminogen activator, urokinase- type plasminogen activator, plasminogen activator inhibitor antigen, and complex formation of plasmin alpha 2-antiplasmin (P = .0078 for each). Plasminogen activator inhibitor activity was also reduced, but not significantly according to the Hochberg method (P = .0304). The endotoxin-induced activation of the procoagulant state as reflected by increase in F1 + 2 fragments and TAT complexes was blunted by rBPI23 infusion (P = .0391 [not significant according to the Hochberg method] and .0078, respectively). These results indicate that rBPI23 is capable of reducing both the activation of the fibrinolytic and the coagulation systems after low-dose endotoxin infusion in humans. 相似文献
45.
Pediatric patients with achondroplasia: CT evaluation of the craniocervical junction 总被引:2,自引:0,他引:2
Twenty-six patients (4 months to 6 years old) with achondroplasia complicated by sleep apnea and/or other neurologic manifestations underwent plain computed tomography (CT) of the craniocervical junction; six also underwent CT myelography. For objectification, multiplanar reconstruction was used to complement axial plane measurements by providing coronal and sagittal measurements; multiplanar reconstruction also improved perception of the longitudinal relationships between the brain stem and subarachnoid space. A narrow subarachnoid space was found in all 26 patients; marked cord compression was present in nine, six of whom underwent CT myelography. These six had marked focal obliteration of the subarachnoid space on both plain CT and CT myelography. Since the subarachnoid space immediately above and below the craniocervical junction is normally capacious, when marked constriction was present, no additional information could have been gained from CT myelography. Thus, plain CT was shown to be sufficient for surgical planning (suboccipital decompression) in nine patients with cord compression due to achondroplasia. 相似文献
46.
47.
48.
49.
Carriage of Haemophilus influenzae and Streptococcus pneumoniae in healthy Chinese and Vietnamese children in Hong Kong 总被引:1,自引:0,他引:1
RYT Sung JM Ling SM Fung SJ Oppenheimer DW Crook JTF Lau AFB Cheng 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(11):1262-1267
Nasopharyngeal carriage of Haemophilus influenzae and Streptococcus pneumoniae was studied in 621 healthy Chinese children and 300 healthy Vietnamese children aged from 2 months to 5 years in Hong Kong. The carriage rate of H, influenzae type b in Vietnamese children was 1.3% (CI 0.04-2.63%); it was zero in Chinese. The carriage rate of non-typable H. influenzae was 5.8% (CI 1.4-7.6%) in Chinese and 65.4% (CI 58.9-69.8%) in Vietnamese. The carriage rates of S. pneumoniae were 10.8% (CI 8.3-13.2%) and 55.7% (CI 50.1-61.3%) in Chinese and Vietnamese children, respectively. Univariate and multivariate logistic regression analyses were performed to search for factors associated with differences in carriage rates of both H. influenzae and S. pneumoniae between Chinese and Vietnamese children. Although older age, smaller living area and parental smoking were associated with higher carriage rates, these could not explain the remarkably low carriage rates of both bacteria in Chinese children. 相似文献
50.
In the introduction I express the need of introducing the point of view of Ethics when we are dealing with problems of science, technology, and especially medicine. In the first part of my presentation I deal with the problem of the value of human life, coming to the conclusion that human life might not be completely absolute, but is extremely important and “ceteris paribus” should be respected, and the problem of when it starts. Some of the main arguments are discussed. In this connection the question of abortion is briefly discussed. In the second part I deal with some problems related to human reproduction. Most people will be willing to support programmes for treating individuals with genetic disease; but at the same time the dangers of increasing depersonalization of the reproductive process are pointed out. In the third part I take up the problem of In Vitro Fertilisation. IVF has certainly brought benefits to some couples suffering from infertility, but at the same time it has raised quite a few human and moral problems. Is it permissible to fertilise an egg with a donor sperm, replacing the embryo in the womb? What about fertilising a donor egg with the husband's sperm? Is it acceptable to store or freeze embryos for future use? Is it moral to implant such an embryo in a woman who has no genetic relationship with the embryo? Is it moral to use surrogate mothers? Is it moral for ‘spare’ embryos to be killed or used as tissue for research? At the end I stress the need of dialogue between life sciences and ethics. 相似文献