全文获取类型
收费全文 | 1875篇 |
免费 | 119篇 |
国内免费 | 10篇 |
专业分类
耳鼻咽喉 | 17篇 |
儿科学 | 59篇 |
妇产科学 | 29篇 |
基础医学 | 225篇 |
口腔科学 | 59篇 |
临床医学 | 163篇 |
内科学 | 431篇 |
皮肤病学 | 45篇 |
神经病学 | 89篇 |
特种医学 | 174篇 |
外国民族医学 | 1篇 |
外科学 | 214篇 |
综合类 | 64篇 |
预防医学 | 114篇 |
眼科学 | 173篇 |
药学 | 86篇 |
中国医学 | 3篇 |
肿瘤学 | 58篇 |
出版年
2023年 | 9篇 |
2022年 | 19篇 |
2021年 | 27篇 |
2020年 | 24篇 |
2019年 | 34篇 |
2018年 | 53篇 |
2017年 | 46篇 |
2016年 | 33篇 |
2015年 | 47篇 |
2014年 | 42篇 |
2013年 | 69篇 |
2012年 | 85篇 |
2011年 | 91篇 |
2010年 | 75篇 |
2009年 | 76篇 |
2008年 | 82篇 |
2007年 | 68篇 |
2006年 | 62篇 |
2005年 | 52篇 |
2004年 | 79篇 |
2003年 | 53篇 |
2002年 | 44篇 |
2001年 | 46篇 |
2000年 | 41篇 |
1999年 | 42篇 |
1998年 | 59篇 |
1997年 | 69篇 |
1996年 | 71篇 |
1995年 | 46篇 |
1994年 | 46篇 |
1993年 | 41篇 |
1992年 | 16篇 |
1991年 | 19篇 |
1990年 | 20篇 |
1989年 | 23篇 |
1988年 | 30篇 |
1987年 | 29篇 |
1986年 | 29篇 |
1985年 | 17篇 |
1984年 | 15篇 |
1983年 | 16篇 |
1982年 | 25篇 |
1980年 | 9篇 |
1979年 | 11篇 |
1977年 | 9篇 |
1975年 | 10篇 |
1972年 | 9篇 |
1969年 | 8篇 |
1968年 | 9篇 |
1966年 | 11篇 |
排序方式: 共有2004条查询结果,搜索用时 15 毫秒
31.
Alan A. Saber Nami Azar Mahmoud Dekal Tamer N. Abdelbaki 《American journal of surgery》2015,209(6):999-1006
Background
Several postoperative gastrointestinal complications are attributed to ischemia. We herein evaluate the gastric wall perfusion using computed tomography (CT) scan perfusion index on trial to address the etiology of ischemic complication after sleeve gastrectomy.Methods
A retrospective study of 205 patients undergoing CT scan of the abdomen to evaluate the pattern of gastric vascular perfusion was performed. The perfusion index of the gastric mucosa was measured at 5 gastric points using CT perfusion scanning.Results
Gastric perfusion at the angle of His (AOH) (53.51 ± 14.38) was statistically significantly lower (P < .001) than that at the other gastric points studied: fundus, greater curvature, lesser curvature, incisura angularis, and mid gastric points (76.16 ± 15.21, 73.27 ± 16.55, 76.12 ± 16.12, and 75.24 ± 14.9, respectively). Gastric perfusion was significantly lower at all the gastric points (and especially so at the AOH) among obese patients (33 cases) compared with nonobese patients (18 cases). Gastric perfusion at all the points studied showed a decrease as the body mass index increases. Hypertensive patients had a better gastric perfusion compared with nonhypertensive patients.Conclusions
Gastric wall perfusion is statistically significantly decreased at the AOH and gastric fundus compared with perfusion at other gastric points. Gastric perfusion at all the gastric points studied decreased with the increase in body mass index. Gastric leakage in obese patients following sleeve gastrectomy could be attributed to a decrease in the blood supply at AOH. 相似文献32.
The relative importance of thrombin inhibition and factor Xa inhibition to the antithrombotic effects of heparin 总被引:4,自引:1,他引:4
The relative importance of antithrombin and anti-factor Xa activities of heparin fractions required to achieve optimal antithrombotic effects is unknown. To study this, we measured the effects of standard heparin, an octasaccharide heparin fraction (anti-factor Xa activity only), and dermatan sulfate (antithrombin activity only) on the prevention of thrombosis and related this to their anticoagulant effects in vivo in rabbits. Thrombosis was measured as the incorporation of 125I- fibrinogen into tissue thromboplastin-induced thrombi using a Wessler- type model. Ex vivo changes in thrombin clotting time (TCT) were used as an index of antithrombin activity, and a chromogenic anti-factor Xa assay was used to measure anti-factor Xa activity. In addition, the ability of the three sulfated polysaccharides to simultaneously inhibit the generation of thrombin activity and to enhance the inactivation of the factor Xa added to initiate thrombin generation in plasma was determined. Standard heparin, in a dose of 10 anti-factor Xa U/kg, inhibited thrombus formation by 90%, prolonged the TCT by two seconds, and resulted in an anti-factor Xa level of 0.32 U/mL. The octasaccharide heparin fraction, in a dose of 10 anti-factor Xa U/kg, inhibited thrombus formation by 41%, had no effect on the TCT, and resulted in an anti-factor Xa level of 0.28 U/mL. Higher doses of the octasaccharide resulted in a further increase in the anti-factor Xa levels but had no further effect on thrombus formation. Dermatan sulfate, in a dose of 500 micrograms/kg, inhibited thrombus formation by 95%, but had no affect on the TCT. These results indicate that the antithrombotic effect achieved by inhibiting factor Xa is limited and that better antithrombotic effects are achieved by heparin or heparin- like substances capable of influencing the inactivation and/or the generation of thrombin. 相似文献
33.
34.
35.
36.
Nari GA Azar R Feliu L Moreno E Bonaparte F 《Acta gastroenterologica Latinoamericana》2012,42(1):53-55
We present a patient with acute abdomen and digestive bleeding caused by jejunal diverticulosis. Jejunal diverticulosis, mainly asymptomatic, when is symptomatic have a wide clinical spectrum, ranging from chronic anemic syndrome to acute abdomen. In this communication, we reviewed the clinical presentation, the pathogenesis and the treatment this infrequent pathology. 相似文献
37.
38.
39.
Unfortunately, the only approved medical treatment for type 1 diabetes mellitus (DM) is insulin, despite the fact that tight control cannot be reached without some serious side effects such as hypoglycemia and weight gain. More and more importance is now shifted towards developing new drugs that can reach a better glycemic control with lesser side effects. Some of these promising drugs are the glucagon-like peptides 1 (GLP-1) and their agonists, which have been FDA approved for the treatment of type 2 DM. The purpose of this article is to review all of the relevant literature on the potential role of GLP-1 in the treatment of type 1 DM. The major source of data acquisition included Medline search strategies, using the words "type 1 diabetes mellitus" and "GLP-1." Articles published in the last 20?years were screened. GLP-1 increases insulin secretion in humans with existing beta cells; it also decreases glucagon secretion, and blunts appetite. Of note, new animal studies demonstrate a role in beta cell-proliferation and decreased apoptosis. Because of all the effects mentioned above, GLP-1 seems to be a promising drug for type 1 DM treatment, but more studies are still needed before solid conclusions can be drawn. 相似文献
40.