首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   952篇
  免费   62篇
  国内免费   59篇
儿科学   45篇
妇产科学   6篇
基础医学   53篇
口腔科学   19篇
临床医学   149篇
内科学   255篇
皮肤病学   17篇
神经病学   18篇
特种医学   229篇
外科学   68篇
综合类   28篇
预防医学   50篇
眼科学   8篇
药学   99篇
中国医学   8篇
肿瘤学   21篇
  2022年   4篇
  2021年   12篇
  2020年   4篇
  2019年   4篇
  2018年   16篇
  2017年   3篇
  2016年   3篇
  2015年   21篇
  2014年   19篇
  2013年   33篇
  2012年   28篇
  2011年   27篇
  2010年   29篇
  2009年   23篇
  2008年   20篇
  2007年   55篇
  2006年   18篇
  2005年   23篇
  2004年   27篇
  2003年   19篇
  2002年   22篇
  2001年   17篇
  2000年   15篇
  1999年   16篇
  1998年   53篇
  1997年   36篇
  1996年   61篇
  1995年   44篇
  1994年   41篇
  1993年   50篇
  1992年   11篇
  1991年   11篇
  1990年   19篇
  1989年   30篇
  1988年   35篇
  1987年   35篇
  1986年   26篇
  1985年   29篇
  1984年   17篇
  1983年   12篇
  1982年   13篇
  1981年   23篇
  1980年   19篇
  1979年   6篇
  1978年   9篇
  1977年   15篇
  1976年   7篇
  1975年   10篇
  1970年   1篇
  1963年   1篇
排序方式: 共有1073条查询结果,搜索用时 0 毫秒
1.
2.
3.
4.
AIMS: To define outcome measures for auditing the clinical care of children and adolescents with insulin dependent diabetes mellitus (IDDM) and to assess the benefit of appointing a dedicated paediatric trained diabetes specialist nurse (PDSN). METHODS: Retrospective analysis of medical notes and hospital records. Glycaemic control, growth, weight gain, microvascular complications, school absence, and the proportion of children undergoing an annual clinical review and diabetes education session were assessed. The effect of the appointment of a PDSN on the frequency of hospital admission, length of inpatient stay, and outpatient attendance was evaluated. RESULTS: Children with IDDM were of normal height and grew well for three years after diagnosis, but grew suboptimally thereafter. Weight gain was above average every year after diagnosis. Glycaemic control was poor at all ages with only 16% of children having an acceptable glycated haemoglobin. Eighty five per cent of patients underwent a formal annual clinical review, of whom 16% had background retinopathy and 20% microalbuminuria in one or more samples. After appointing the PDSN the median length of hospital stay for newly diagnosed patients decreased from five days to one day, with 10 of 24 children not admitted. None of the latter was admitted during the next year. There was no evidence of the PDSN affecting the frequency of readmission or length of stay of children with established IDDM. Non-attendance at the outpatient clinic was reduced from a median of 19 to 10%. CONCLUSIONS: Outcome measures for evaluating the care of children with IDDM can be defined and evaluated. Specialist nursing support markedly reduces the length of hospital stay of newly diagnosed patients without sacrificing the quality of care.  相似文献   
5.
The androgen insensitivity syndrome is a heterogeneous disorder with a wide spectrum of phenotypic abnormalities, ranging from complete female to ambiguous forms that more closely resemble males. The primary abnormality is a defective androgen receptor protein due to a mutation of the androgen receptor gene. This prevents normal androgen action and thus leads to impaired virilisation. A point mutation of the androgen receptor gene affecting two siblings with partial androgen insensitivity syndrome is described. One had cliteromegaly and labial fusion and was raised as a girl, whereas the other sibling had micropenis and penoscrotal hypospadias and was raised as a boy. Both were shown to have the arginine 840 to cysteine mutation. The phenotypic variation in this family is thus dependent on factors other than abnormalities of the androgen receptor gene alone.  相似文献   
6.
Autoimmune thrombocytopenic purpura (AITP) is a bleeding disease in which autoantibodies are directed against the individual's own platelets, resulting in enhanced Fc-mediated platelet destruction by macrophages in the reticuloendothelial system. Most research in AITP has focused on characterization of the autoantibodies, while little has been devoted to the cellular immune mechanisms leading to autoantibody production. This report summarizes the current state of the literature and argues that enhanced T helper cell/antigen-presenting cell interactions in patients with AITP are the primary stimulus for the development of antiplatelet autoantibody production. Understanding these events is important for eventually identifying disease-initiating platelet autoantigens and ultimately developing specific immunotherapies for AITP.  相似文献   
7.
8.
Miller JA  Thai K  Scholey JW 《Diabetes》2000,49(9):1585-1589
Recent studies suggest that there is an association between the A1166-->C polymorphism of the angiotensin II type 1 receptor (AGT1R), glycemic control, and the risk of diabetic nephropathy in subjects with type 1 diabetes. Because hypertension and renal hemodynamic function are also related to the risk of diabetic nephropathy and because hyperglycemia can activate the renin angiotensin system, we sought to determine if there is an association between the AGT1R polymorphism, baseline renal and peripheral hemodynamic function, and pressor response to high glucose in subjects with early uncomplicated type 1 diabetes. There were 39 diabetic subjects genotyped for the AGT1R polymorphism by polymerase chain reaction and segregated into 2 groups: those with and those without the C1166 allele (AA and AC/CC). The average age was 27 +/- 1 years, and the mean duration of diabetes was 3.5 +/- 0.6 years. HbA(1c) values were <10% in all subjects and were similar in the 2 groups (8.2 +/- 0.3 vs. 9.1 +/- 0.4%). After a 7-day controlled diet (150 mmol sodium, 1.5-2.0 g x kg(-1) x day(-1) protein), renal hemodynamic function was assessed by inulin and para-aminohippurate clearance during clamped euglycemic conditions (4-6 mmol/l). Mean values for glomerular filtration rates did not differ between groups during euglycemia. In contrast, mean values for renal plasma flow and renal blood flow were significantly greater in the AC/CC group compared with the AA group. Values for mean arterial pressure were similar in the 2 groups, whereas renal vascular resistance was significantly reduced in the AC/CC group. In 20 subjects (10 from each genotype subgroup), hemodynamic function was assessed on a second occasion during controlled clamped hyperglycemia (9-11 mmol/l) after a similar preparatory period. In response to high glucose, plasma renin activity increased in both genotype groups to the same extent, but a pressor response was noted only in subjects with the C1166 allele. Mean arterial pressure increased significantly in the AC/CC subgroup and remained unchanged in the AA subgroup. We conclude that there is an association between the AGT1R A1166-->C polymorphism and renal hemodynamic function in early type 1 diabetes. But more importantly, the pressor response to hyperglycemia is augmented in those diabetic patients with the C1166 allele and may represent a factor that predisposes them to renal injury during periods of inadequate glucose control.  相似文献   
9.
Two groups of adult male trainees of varying levels of retardation were instructed and monitored over a period of 9 months in various aspects of social education. The training took place in an up-graded home-orientated atmosphere. Group A and B together showed an increase of 44 per cent in skill competence over the 9 month period and 46 per cent increase over the control group.  相似文献   
10.
Nakamura  H; Said  JW; Miller  CW; Koeffler  HP 《Blood》1993,82(3):920-926
p53 mutations are found in a variety of neoplasia. B-immunoblastic lymphoma (BIBL) is a rapidly progressive, aggressive lymphoma. As patients with acquired immunodeficiency syndrome (AIDS) live longer, BIBL is becoming an increasing problem. We asked three questions in our study. What is the frequency of p53 mutations in BIBL? Is it more frequent in patients with AIDS? Can immunohistochemical staining of lymph nodes for expression of p53 substitute for mutational analysis of p53 to detect lymphomas with mutated p53? Exons 5, 6, 7, 8 of the p53 gene (hot-spots for mutations) were amplified and examined for mutations by single-strand conformation polymorphism (SSCP) analysis. Altered migration was observed in 7 of 52 BIBL samples. Of these, 4 of 25 were from individuals infected with human immunodeficiency virus (HIV) and 3 of 27 were not infected with HIV. Direct sequencing of amplified material confirmed the presence of mutations in exons 5, 7, 8 of p53. A total of 26 BIBL as well as other lymphoma/leukemia samples, stained strongly by immunohistochemistry with three antibodies directed against human p53. Five of 6 BIBL samples with p53 mutations stained strongly for p53, but 20 lymphoma samples with no detectable p53 mutations also stained strongly for p53. Of note, however, 10 hyperplastic, nonmalignant lymph nodes from individuals either infected or not infected with HIV had negligible staining for p53 protein. In conclusion, p53 mutations occur in about 14% BIBL samples; the frequency of p53 mutations in BIBL in individuals with and without AIDS was similar. Positive p53 immunohistochemistry did not correlate with detectable p53 mutations in the same tissue, but positive immunohistochemical staining for p53 was only found in neoplastic lymph nodes. This latter finding provides a strong warning that p53 immunochemistry with available reagents cannot be used to determine which tumors have mutations of p53.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号