全文获取类型
收费全文 | 404篇 |
免费 | 10篇 |
国内免费 | 18篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 14篇 |
妇产科学 | 18篇 |
基础医学 | 61篇 |
口腔科学 | 5篇 |
临床医学 | 41篇 |
内科学 | 109篇 |
皮肤病学 | 1篇 |
神经病学 | 12篇 |
特种医学 | 82篇 |
外科学 | 28篇 |
综合类 | 5篇 |
预防医学 | 13篇 |
眼科学 | 1篇 |
药学 | 32篇 |
肿瘤学 | 9篇 |
出版年
2023年 | 1篇 |
2021年 | 6篇 |
2020年 | 3篇 |
2019年 | 1篇 |
2018年 | 5篇 |
2017年 | 3篇 |
2016年 | 4篇 |
2015年 | 4篇 |
2014年 | 6篇 |
2013年 | 3篇 |
2012年 | 11篇 |
2011年 | 8篇 |
2010年 | 11篇 |
2009年 | 18篇 |
2008年 | 17篇 |
2007年 | 29篇 |
2006年 | 17篇 |
2005年 | 17篇 |
2004年 | 13篇 |
2003年 | 6篇 |
2002年 | 13篇 |
2001年 | 16篇 |
2000年 | 16篇 |
1999年 | 10篇 |
1998年 | 20篇 |
1997年 | 10篇 |
1996年 | 13篇 |
1995年 | 16篇 |
1994年 | 11篇 |
1993年 | 11篇 |
1992年 | 3篇 |
1991年 | 10篇 |
1990年 | 6篇 |
1989年 | 15篇 |
1988年 | 13篇 |
1987年 | 8篇 |
1986年 | 14篇 |
1985年 | 11篇 |
1984年 | 5篇 |
1983年 | 4篇 |
1982年 | 3篇 |
1981年 | 5篇 |
1980年 | 6篇 |
1977年 | 3篇 |
1976年 | 1篇 |
1975年 | 5篇 |
1965年 | 1篇 |
排序方式: 共有432条查询结果,搜索用时 31 毫秒
1.
2.
Occurrence of the t(2;5)(p23;q35) in non-Hodgkin's lymphoma 总被引:9,自引:3,他引:6
Weisenburger DD; Gordon BG; Vose JM; Bast MA; Chan WC; Greiner TC; Anderson JR; Sanger WG 《Blood》1996,87(9):3860-3868
Primary CD30(Ki-1)-positive anaplastic large-cell lymphoma (ALCL) is considered by some to be a distinct clinicopathologic entity associated with the t(2;5) (p23;q35). However, the specificity of t(2;5) for ALCL has not been carefully studied. Therefore, we performed a detailed analysis of all cases of ALCL with abnormal cytogenetics results in the Nebraska Lymphoma Study Group registry, as well as all other cases of non-Hodgkin's lymphoma with t(2;5) in the registry. We found the t(2;5) in only five of 10 cases of ALCL, four of whom were young patients. However, we also found the t(2;5) in 11 other cases of nonanaplastic lymphoma, including eight children with typical peripheral T-cell lymphomas of various types. The t(2;5) was also found in three older adults with B-cell lymphomas of various types. Thus, the t(2;5) was not specific for CD30+ ALCL. However, t(2;5) may define a clinicopathologic entity in children and young adults characterized by variable morphologies with a T-cell or indeterminate phenotype, CD30-positivity, nodal disease with frequent extranodal involvement, advanced stage, and an excellent response to therapy, including bone marrow transplantation for relapsed disease. The clinical relevance of the t(2;5) in older patients requires further study. 相似文献
3.
The magnetic resonance (MR) images of six patients with thrombosis of a dural sinus were reviewed. The diagnosis had been verified by computed tomographic scans in three patients and arteriograms in two; in the sixth patient, only MR imaging was used to confirm the clinical syndrome. In all patients, high-intensity signal was seen from the thrombus within the affected dural sinus on all echoes. This persistent signal intensity allowed intravascular clot to be distinguished from normal causes of increased signal such as flow-related enhancement (entry phenomenon) and even-echo rephasing. MR imaging demonstrated the cause of the thrombosis in three patients: two were secondary to adjacent tumors, and one was secondary to unsuspected mastoiditis. Complications such as infarction were also demonstrated. Using MR imaging, one can easily and safely diagnose thrombosis of a dural sinus. MR should be the imaging method of choice in patients suspected of having thrombosis of a dural sinus. 相似文献
4.
Limited-field-of-view radio-frequency receiver antennas provide improved near-field sensitivity for magnetic resonance imaging by decreasing the antenna volume. The Helmholtz-type surface coil, consisting of two flat rings, is an organ-encompassing antenna that takes advantage of this principle to yield an improved signal-to-noise ratio (S/N). The coil was tested in a group of 50 patients and 16 healthy volunteers. Images obtained with the Helmholtz coil demonstrated quantitatively superior S/N of 2.2-fold or greater than that of comparison body coil images, as well as qualitatively superior anatomic resolution. 相似文献
5.
Low-artifact intravascular devices: MR imaging evaluation 总被引:2,自引:0,他引:2
Teitelbaum GP; Ortega HV; Vinitski S; Stern H; Tsuruda JS; Mitchell DG; Rifkin MD; Bradley WG Jr 《Radiology》1988,168(3):713-719
Flow-phantom magnetic resonance (MR) imaging, with use of both spin-echo (SE) and gradient-echo (GRE) techniques at 1.5 T, was performed on the percutaneous Greenfield (beta-III titanium alloy [TMA wire]), Amplatz (MP32-N alloy), and Simon nitinol filters and TMA wire facsimiles of the bird's nest, Gunther, new retrievable, and Amplatz vena caval filters. SE imaging allowed detection of thrombi as small as 5 X 5 mm trapped within the percutaneous Greenfield, Simon nitinol, and TMA-wire facsimile filters; with the MP32-N Amplatz filter, a larger volume of thrombus (10 X 20-mm clots) was necessary for clot detection. GRE imaging allowed detection of intraluminal tilting of the percutaneous Greenfield and facsimile Amplatz (TMA-wire) filters. GRE imaging was useful for demonstrating postfilter turbulence due to clots, which was greatest for the Amplatz filter. Imaging of facsimile vascular devices made of tantalum or TMA wire did not cause the severe "black-hole" MR artifacts typical of the stainless-steel devices. SE and GRE imaging were very useful for determining caval patency in two patients with previously placed Mobin-Uddin filters. Noninvasive MR evaluation of blood vessels in the presence of a variety of low-artifact intravascular devices appears feasible. 相似文献
6.
7.
8.
9.
Guidelines for the appropriate use of genetic tests in infertile couples 总被引:10,自引:0,他引:10
Foresta C Ferlin A Gianaroli L Dallapiccola B 《European journal of human genetics : EJHG》2002,10(5):303-312
Research on genetic causes of male and female infertility rapidly expanded in the last years, following the development of in vitro fertilising techniques. Genetic tests are now available to explore the cause of the infertility and assess the risk of a given couple to transmit its genetic characteristics. This allows at-risk couples to take an informed decision when electing for a medically assisted reproduction. It also allows the professionals to offer a prenatal diagnosis when appropriate. Thus, the genetic work-up of the infertile couple has become good practice for an appropriate diagnosis, treatment and prognostic assessment. The lack of national or international rules for the genetic approach to the infertile couple, prompted the Italian community of professionals in the field of reproductive medicine to join and set up guidelines for the genetic diagnosis of male and female infertility. The group of clinical and research experts is representative of 12 national scientific societies and was supported by external experts from four international societies. We examine the clinically relevant genetic causes of male and female infertility and suggest the category of patients for which each genetic test is recommended or optional, both for an accurate diagnosis and prior to ART. 相似文献
10.
Atrial automaticity and atrioventricular conduction in athletes: contribution of autonomic regulation 总被引:2,自引:0,他引:2
Stein R Moraes RS Cavalcanti AV Ferlin EL Zimerman LI Ribeiro JP 《European journal of applied physiology》2000,82(1-2):155-157
Little is known about the sinoatrial automatism and atrioventricular conduction of trained individuals who present a normal
resting electrocardiogram. We used transesophageal atrial stimulation, a minimally invasive technique, to evaluate aerobically
trained athletes (n=10) and sedentary individuals (n=10) with normal resting electrocardiograms, to test the hypothesis that parasympathetic tone, as detected by heart rate variability,
could be associated with changes in sinoatrial automatism and atrioventricular conduction. Corrected sinus node recovery time
tended to be longer in athletes than in sedentary individuals, but this difference did not reach statistical significance.
The Wenckebach point occurred at a lower rate in athletes than in the controls. Over a 24-h period of measurement, the mean
RR interval was longer in the athletes than in the sedentary individuals. The mean square root of successive differences (rMSSD)
tended to be higher in athletes than in controls, but this difference did not reach statistical significance. There was a
moderate correlation (r=0.48, P < 0.05) between the index of atrioventricular conduction, the rate at the Wenckebach point, and the logarithmically transformed
rMSSD. Thus, as a corollary to its effects on the sinus node, where increased parasympathetic tone, decreased sympathetic
tone, and non-autonomic components may contribute to sinus bradycardia, it is possible that athletic training may also induce
intrinsic adaptations in the conduction system, which could contribute to the higher prevalence of atrioventricular conduction
abnormalities observed in athletes.
Accepted: 2 January 2000 相似文献