全文获取类型
收费全文 | 1348篇 |
免费 | 77篇 |
国内免费 | 46篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 43篇 |
妇产科学 | 39篇 |
基础医学 | 198篇 |
口腔科学 | 44篇 |
临床医学 | 109篇 |
内科学 | 219篇 |
皮肤病学 | 38篇 |
神经病学 | 177篇 |
特种医学 | 62篇 |
外科学 | 101篇 |
综合类 | 5篇 |
预防医学 | 87篇 |
眼科学 | 88篇 |
药学 | 132篇 |
中国医学 | 2篇 |
肿瘤学 | 121篇 |
出版年
2023年 | 10篇 |
2021年 | 30篇 |
2020年 | 11篇 |
2019年 | 26篇 |
2018年 | 35篇 |
2017年 | 22篇 |
2016年 | 30篇 |
2015年 | 32篇 |
2014年 | 40篇 |
2013年 | 62篇 |
2012年 | 69篇 |
2011年 | 92篇 |
2010年 | 52篇 |
2009年 | 45篇 |
2008年 | 90篇 |
2007年 | 116篇 |
2006年 | 88篇 |
2005年 | 90篇 |
2004年 | 62篇 |
2003年 | 55篇 |
2002年 | 60篇 |
2001年 | 15篇 |
2000年 | 15篇 |
1999年 | 13篇 |
1998年 | 25篇 |
1997年 | 21篇 |
1996年 | 21篇 |
1995年 | 14篇 |
1994年 | 9篇 |
1993年 | 5篇 |
1992年 | 9篇 |
1991年 | 11篇 |
1990年 | 12篇 |
1989年 | 10篇 |
1988年 | 17篇 |
1987年 | 5篇 |
1986年 | 14篇 |
1985年 | 8篇 |
1982年 | 5篇 |
1981年 | 6篇 |
1980年 | 6篇 |
1977年 | 5篇 |
1967年 | 5篇 |
1933年 | 8篇 |
1932年 | 8篇 |
1931年 | 5篇 |
1930年 | 4篇 |
1929年 | 4篇 |
1928年 | 4篇 |
1923年 | 5篇 |
排序方式: 共有1471条查询结果,搜索用时 171 毫秒
1.
Background
Reports on childhood cancer survivors estimated cumulative probability of developing secondary neoplasms vary from 3,3% to 25% at 25 years from diagnosis, and the risk of developing another cancer to several times greater than in the general population. 相似文献2.
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
3.
Ana Berta Sousa Ana Medeira Binita M Kamath Nancy B Spinner Isabel Cordeiro 《Revista portuguesa de cardiologia》2006,25(4):447-452
Although most congenital heart defects are isolated abnormalities of embryonic development, with little genetic contribution, a small number are components of syndromes. In such cases, an accurate diagnosis has important implications for individual prognosis and familial genetic counseling. Alagille syndrome (AGS) is a dominantly inherited multisystem developmental disorder, which primarily affects the liver, heart, eyes, skeleton, and face. In recent years, the identification of the AGS gene has drawn attention to the existence of subclinical carriers, and broadened the spectrum of phenotypical variation associated with this syndrome. The authors present a case of mother and son with benign stenosis of the pulmonary artery branches. Subtle facial aspects suggested the diagnosis of AGS, which was confirmed by molecular analysis. Relevant clinical investigations and diagnostic implications are discussed. 相似文献
4.
We used arthrotomography to study the glenoid labrum in 114 patients. Sixty-nine of the patients had anatomic instability of the shoulder (including recurrent dislocation and subluxation of the shoulder), and 45 patients had functional instability of the shoulder (denoted by chronic pain, clicking of the joint, and the sensation that an unstable condition exists without the objective signs of it). Labral tears were revealed arthrotomographically in 86% of the patients with anatomic instability, while only 40% of the patients with functional instability had labral abnormalities, and these were primarily of minor severity. Fifty-six patients (44 of whom had anatomic instability; 12, functional instability) required surgery. The surgical findings were correlated with the arthrotomographic findings, and no false-positive results were revealed. However, arthrotomography demonstrated only part of the pathologic condition of two patients. These results confirm that there is a strong correlation between labral pathologic conditions and anatomic instability of the shoulder. Arthrotomographic studies have a great impact on the selection of therapy in cases of both anatomic and functional instability of the shoulder. 相似文献
5.
Suzanne D. LeBlang M.D. Diego B. Nuñez M.D. Anton Serafini M.D. Robert C. Duncan Ph.D. M. Judith Donovan Post M.D. Berta M. Montalvo M.D. Jose I. Becerra M.D. 《Emergency radiology》1997,4(4):191-199
The purpose of this study was to evaluate the ability of helical computed tomography (CT) to detect arterial injuries in gunshot wounds to the neck. In a blinded retrospective review, 54 helical CT scans of the cervical spine were evaluated for bullet/bone fragments, subcutaneous air, bullet path, hematoma, spine fractures, and pharyngoesophageal compromise. The distance of fragments to a major vessel was calculated. CT findings that correlated significantly with major arterial injury included the presence of fragments (bullet/bone) close to a major vessel (2.5 mm) and spine fractures. Visualizing fragments <5 mm from a vessel or a transcervical bullet trajectory predicted 12 of 13 major arterial injuries. We conclude that CT clearly depicts anatomic damage. Specific findings, such as the location of fragments and bullet trajectory adjacent to a vessel and spine fractures, indicate a higher probability of vascular damage, thus directing more definitive evaluation. 相似文献
6.
Years of speculations about the nature of the elusive testis determining factor (TDF) of the Y chromosome have ended last year. A gene named SRY satisfies many criteria expected of the testis determining gene, and gives us a basis to understand molecular mechanisms of the testis differentiation. The different steps which gave rise to SRY cloning are described. 相似文献
7.
L Berta N Fortunati P Gennari M Appendino A Casella R Frairia 《Fertility and sterility》1991,56(4):788-789
Plasma gonadotropin FSH and LH, PRL, sex steroids (17-beta E2, E1, and P), SBP binding capacity, and urine estrogens (E1, E2, and E3) were measured in 485 premenopausal healthy women, subdivided according to smoking habits. The aim of the study was to verify if cigarette smoking influences sex hormone balance. Baseline PRL levels were significantly lower (P less than 0.002) in smoker (n = 174) than in nonsmoker (n = 311) women. No difference was found in the other parameters of the two groups, particularly in plasma and urine estrogenic pattern. Our data suggest that smoking directly affects PRL levels by involving the hypothalamic mechanism that regulates PRL secretion. 相似文献
8.
Berbaum KS; el-Khoury GY; Franken EA Jr; Kathol M; Montgomery WJ; Hesson W 《Radiology》1988,168(2):507-511
The effect of knowledge of localizing symptoms and signs in the detection of fractures was studied. Forty radiographs of the extremities were examined twice by seven radiologists; the sessions were separated by 4 months. In 26 cases, a subtle fracture was present; 14 cases were normal. In half of the cases at each session, the precise location of pain, tenderness, or swelling was provided. The observer was asked to determine if the case was normal or abnormal (provide the exact location of the fracture) and to indicate the degree of confidence in the diagnosis. Responses were converted to a numeric scale for analysis. Analysis of receiver operator characteristic parameters indicates that clues regarding location of trauma facilitate detection of fractures. The improvement is based largely on an increased true-positive rate without an increased false-positive rate, regardless of the decision criteria of the radiologist (overall willingness to "overread" or "underread"). This has direct clinical applicability and reinforces the plea of radiologists for precise clinical information. 相似文献
9.
Effect of Histamine Receptor Blocking on Human Antibody-dependent Cell-mediated Cytotoxicity 总被引:1,自引:0,他引:1
I. LÁNG K. TÖRÖK P. GERGELY K. NÉKÁM GY. PETRÁNYI 《Scandinavian journal of immunology》1981,13(4):361-366
The effect of H1 and H2 receptor-blocking agents on antibody-dependent cell-mediated cytotoxicity (ADCC) was studied. The H1 receptor-blocker clemastinum and the H2 receptor blocker cimetidine dose-dependently inhibited the antibody-dependent cytotoxic activity of normal human peripheral blood mononuclear cells on chicken erythrocytes. The inhibition cannot be explained either by a direct toxic effect on effector cells or by blocking of Fc receptors. The possible involvement of histamine receptor-bearing effector cells in human ADCC is suggested. 相似文献
10.
Alberto Utrero-Rico Javier Ruiz-Hornillos Cecilia González-Cuadrado Claudia Geraldine Rita Berta Almoguera Pablo Minguez Antonio Herrero-González Mario Fernández-Ruiz Octavio Carretero Juan Carlos Taracido-Fernández Rosario López-Rodriguez Marta Corton José María Aguado Luisa María Villar Carmen Ayuso-García Estela Paz-Artal Rocio Laguna-Goya 《The Journal of allergy and clinical immunology》2021,147(5):1652-1661.e1