全文获取类型
收费全文 | 878篇 |
免费 | 89篇 |
专业分类
耳鼻咽喉 | 7篇 |
儿科学 | 26篇 |
妇产科学 | 14篇 |
基础医学 | 90篇 |
口腔科学 | 24篇 |
临床医学 | 136篇 |
内科学 | 111篇 |
皮肤病学 | 12篇 |
神经病学 | 150篇 |
特种医学 | 34篇 |
外科学 | 53篇 |
综合类 | 14篇 |
一般理论 | 53篇 |
预防医学 | 96篇 |
眼科学 | 7篇 |
药学 | 101篇 |
肿瘤学 | 39篇 |
出版年
2021年 | 13篇 |
2020年 | 7篇 |
2019年 | 8篇 |
2018年 | 12篇 |
2017年 | 8篇 |
2016年 | 15篇 |
2015年 | 21篇 |
2014年 | 22篇 |
2013年 | 24篇 |
2012年 | 53篇 |
2011年 | 53篇 |
2010年 | 21篇 |
2009年 | 19篇 |
2008年 | 32篇 |
2007年 | 43篇 |
2006年 | 31篇 |
2005年 | 36篇 |
2004年 | 36篇 |
2003年 | 45篇 |
2002年 | 39篇 |
2001年 | 28篇 |
2000年 | 30篇 |
1999年 | 29篇 |
1998年 | 13篇 |
1997年 | 11篇 |
1996年 | 11篇 |
1995年 | 7篇 |
1994年 | 7篇 |
1992年 | 8篇 |
1991年 | 19篇 |
1990年 | 8篇 |
1989年 | 9篇 |
1988年 | 14篇 |
1987年 | 11篇 |
1986年 | 9篇 |
1985年 | 8篇 |
1984年 | 13篇 |
1983年 | 7篇 |
1979年 | 16篇 |
1978年 | 7篇 |
1975年 | 11篇 |
1974年 | 11篇 |
1973年 | 9篇 |
1972年 | 10篇 |
1971年 | 12篇 |
1970年 | 9篇 |
1969年 | 12篇 |
1968年 | 17篇 |
1967年 | 14篇 |
1966年 | 14篇 |
排序方式: 共有967条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
Charlotte J. Harden Bernard M. Corfe J. Craig Richardson Peter W. Dettmar Jenny R. Paxman 《Nutrition Research》2009
This cross-sectional analysis evaluated the effect of age and body mass index (BMI) on Three-Factor Eating Questionnaire scores in males. Subjects (n = 60) were recruited according to BMI status. Each completed the 51-item Three-Factor Eating Questionnaire. The group was split at the median age to produce a “younger” and “older” group for statistical analysis. A 2-way between-groups analysis of variance revealed a significant main effect of BMI on disinhibition (P = .003) and hunger (P = .041) with higher levels found in overweight males compared to healthy-weight counterparts. A significant main effect of age on hunger (P = .046) demonstrated older males were less susceptible to hunger than younger males. These insights provide a better understanding of eating behavior across the male life cycle and may assist health professionals to better guide men in weight management in the light of rising overweight/obesity. 相似文献
5.
Cerebro-oculo-facial-skeletal (COFS) syndrome is a rare, autosomal recessive syndrome characterized by microcephaly, microphthalmia and/or cataracts, neurogenic arthrogryposis, and multiple congenital anomalies. A term female infant with COFS syndrome who developed infantile spasms at the age of 3 months is reported. The patient had a good response to intramuscular ACTH with disappearance of infantile spasms and resolution of the hypsarrhythmic pattern on electroencephalography succeeded by a slow, synchronous pattern. Modified hypsarrhythmia returned after ACTH therapy was discontinued. Infantile spasms have not previously been reported in association with COFS syndrome and are a potentially treatable aspect of the disease. This patient may add to the clinical spectrum of COFS syndrome or may have a variant. 相似文献
6.
Beverly M. Genez M.D. Victor L. Zirilli M.D. Alan E. Schlesinger M.D. Elizabeth A. Harden M.D. Kim D. Murphy M.D. Randall F. Dryer M.D. 《Skeletal radiology》1988,17(4):306-309
The opinions or assertions contained herein are the private views of the authors and are not to be construed as official nor as reflecting the views of the United States Air Force 相似文献
7.
Deletions of interferon genes in acute lymphoblastic leukemia 总被引:16,自引:0,他引:16
M O Diaz C M Rubin A Harden S Ziemin R A Larson M M Le Beau J D Rowley 《The New England journal of medicine》1990,322(2):77-82
Structural rearrangements involving the short arm of chromosome 9, including bands 9p21 and 22, are found in the leukemia cells of 7 to 13 percent of patients with acute lymphoblastic leukemia. The interferon-alpha gene cluster and the interferon-beta 1 gene have been localized to this chromosomal region. We have previously demonstrated deletions of these genes in several cell lines established in vitro from patients with lymphoblastic leukemia. We report here homozygous or hemizygous deletions of the interferon-alpha and interferon-beta 1 genes in samples of leukemia cells from patients with lymphoblastic leukemia. Of 62 patients examined, 18 (29 percent) had such deletions. Four patients (7 percent) had homozygous deletions of the interferon-alpha gene cluster; of these, one also had a homozygous deletion and three had hemizygous deletions of the interferon-beta 1 gene. Fourteen patients (23 percent) had hemizygous deletions of both the interferon-alpha gene cluster and the interferon-beta 1 gene. In 8 of the 18 patients with deletions, the deletions of interferon genes were submicroscopic; in the 11 other patients, chromosomal rearrangements of 9p, including translocations or deletions, were visible on light microscopy. These chromosomal and molecular deletions are likely to be related to the loss of a tumor-suppressor gene (or genes) located on 9p, which may be an interferon gene or an unrelated but closely linked gene. 相似文献
8.
9.
Demonstration of phenotypic abnormalities of thymic epithelium in thymoma including two cases with abundant Langerhans cells. 总被引:1,自引:0,他引:1
下载免费PDF全文
![点击此处可从《The American journal of pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
V. B. Kraus E. A. Harden B. Wittels J. O. Moore B. F. Haynes 《The American journal of pathology》1988,132(3):552-562
A panel of monoclonal antibodies that phenotypically define stages of normal human thymic epithelial (TE) cell maturation was used to compare thymic epithelium of nine thymomas with hyperplastic thymic epithelium in myasthenia gravis (MG) and thymic epithelium of normal thymuses. It has been shown previously that normal thymic epithelial cells express antigens of early TE cell maturation (A2B5, TE-4) throughout thymic ontogeny and acquire antigens 12/1-2, TE8, and TE-15 at 14 to 16 weeks of fetal gestation. Hyperplastic MG thymic epithelial cells expressed TE antigens in phenotypic patterns similar to that seen in normal postnatal thymus, ie, TE in subcapsular cortex and medulla was TE4+, A2B5+, and 12/1 - 2+ and Hassall's bodies were reactive with antibodies TE8 and TE15. In contrast, thymic epithelium in primary mediastinal thymomas was TE4+, A2B5+, TE8-, and greater than 75% of thymoma epithelium was 12/1 - 2-, a thymic epithelial phenotype similar to that seen on normal fetal thymic epithelium at 14 to 16 weeks fetal gestation. In one subject with a mature epithelial histologic pattern, thymoma epithelium was found to be strongly TE8+, a phenotype suggestive of a later stage of TE maturation. Lymphocytes in five of seven thymomas with immature thymic epithelial cells predominantly expressed immature thymocyte phenotype while two thymomas with immature epithelial phenotype showed a predominance of Langerhans cells and surrounding lymphocytes expressing a mature phenotype. Lymphocytes in the thymoma with differentiated epithelial cells expressed a mature thymocyte phenotype. Thus, in thymomas of varying histologic types, phenotypic abnormalities of thymic epithelium are present; these phenotypic abnormalities may reflect abnormal thymic epithelial maturation. 相似文献
10.
1 The metabolism of extracellular nucleotides plays an important role in nucleotide signalling mediated by P2 receptors. The nucleotide sequence encoding a putative human ecto-ATPase named CD39L1 was reported recently. However, the biological activity of this protein has not been established. 2 Based on the sequence of CD39L1 we isolated from mRNA from human ECV-304 cells a sequence encoding a 495 amino acid protein that is identical to CD39L1, with the exception that this sequence contains a 23 amino acid stretch in the putative extracellular loop that is missing in CD39L1. Partial sequence of a genomic DNA clone indicates that the CD39L1 gene corresponds to an alternative spliced form of the human ecto-ATPase. 3 Stable expression of isolated sequence in NIH-3T3 mouse fibroblasts conferred a marked nucleotide hydrolytic activity consistent with the activity of an ecto-ATPase. 4 The human ecto-ATPase hydrolyzed all naturally occurring nucleoside triphosphates in a Ca(2+)- or Mg(2+)-dependent manner. Nucleoside diphosphates were hydrolyzed at a rate approximately 5% of that of the corresponding triphosphates. The apparent Km and Vmax values were: 394+/-62 microM and 107+/-7 nmol Pi min-1 10(6) cells-1 for the hydrolysis of ATP, and 102+/-33 microM and 4+/-0.4 nmol Pi min-1 10(6) cells-1 for the hydrolysis of ADP, respectively. 5 In conclusion, we report here the cloning and functional expression of a human ecto-ATPase. The study of the biochemical properties and the regulatory mechanisms of ecto-ATPases of defined sequence will be valuable in the definition of their role in nucleotide signalling. 相似文献