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   1075篇
  免费   93篇
  国内免费   16篇
耳鼻咽喉   16篇
儿科学   38篇
妇产科学   17篇
基础医学   66篇
口腔科学   34篇
临床医学   163篇
内科学   216篇
皮肤病学   81篇
神经病学   35篇
特种医学   112篇
外科学   158篇
综合类   74篇
现状与发展   27篇
预防医学   48篇
眼科学   13篇
药学   24篇
中国医学   2篇
肿瘤学   60篇
  2024年   15篇
  2023年   144篇
  2022年   12篇
  2021年   11篇
  2020年   45篇
  2019年   18篇
  2018年   41篇
  2017年   39篇
  2016年   31篇
  2015年   48篇
  2014年   65篇
  2013年   46篇
  2012年   21篇
  2011年   22篇
  2010年   62篇
  2009年   75篇
  2008年   21篇
  2007年   45篇
  2006年   17篇
  2005年   13篇
  2004年   6篇
  2003年   12篇
  2002年   12篇
  2001年   8篇
  2000年   15篇
  1999年   23篇
  1998年   28篇
  1997年   42篇
  1996年   32篇
  1995年   29篇
  1994年   22篇
  1993年   32篇
  1992年   5篇
  1991年   7篇
  1990年   6篇
  1989年   16篇
  1988年   16篇
  1987年   10篇
  1986年   4篇
  1985年   5篇
  1984年   3篇
  1982年   7篇
  1981年   10篇
  1980年   10篇
  1978年   5篇
  1976年   12篇
  1975年   9篇
  1959年   2篇
  1937年   1篇
  1933年   1篇
排序方式: 共有1184条查询结果,搜索用时 93 毫秒
71.
72.
The Acne Disability Index: Usefulness confirmed   总被引:1,自引:0,他引:1  
One hundred and four patients with acne completed a questionnaire derived from the Cardiff Acne Disability Index Questionnaire. In addition, 59% of patients returned an identical follow-up questionnaire 6 months later. Significant disability from acne was identified in many patients, with the median initial Acne Disability Index (ADI) being 6 (maximum possible 15), improving to 3 after treatment. Scores correlated poorly with the clinical severity of acne. The questionnaire proved useful for identifying patients with poor self-image who might benefit from more potent treatment for their acne, and to evaluate the effect of treatment.  相似文献   
73.
74.
Anastasi  J; Feng  J; Le Beau  MM; Larson  RA; Rowley  JD; Vardiman  JW 《Blood》1993,81(6):1580-1585
Clonality in myelodysplastic syndromes (MDS) has been studied with various techniques including glucose-6-phosphate dehydrogenase (G6PD) isoenzyme and cytogenetic analyses, and with molecular techniques such as gene deletion studies and the analysis of restriction fragment- length polymorphisms (RFLP) of X-linked genes. In this study, we investigated the use of fluorescence in situ hybridization (FISH) with a chromosome-specific probe to examine cytogenetic clonality in peripheral blood (PB) cells from three patients with MDS. In each case, trisomy 8 was shown by conventional cytogenetic analysis at the time of the initial diagnosis. By using FISH with a probe for the centromere of chromosome 8, we identified the trisomy in individual PB cells from Wright-stained smears. With this technique, we could determine the cell lineage involved by the trisomy, and through serial analyses we could assess the response of the clonal and nonclonal cells to growth-factor therapy, and the expansion of the trisomic clone over time. In each of the three cases, various proportions of granulocytes, monocytes, eosinophils, and basophils showed trisomy 8 by FISH analysis. In none of the cases did we detect trisomy 8 in lymphocytes. By analysis of PB cells before and during therapy with recombinant granulocyte-macrophage colony-stimulating factor (GM-CSF), we found that GM-CSF stimulated both trisomic and disomic cells. During a 1-year period of sequential study, we detected an abrupt increase in the percentage of trisomic cells in one patient, a stable percentage in another, and a slowly increasing percentage in the third. The abrupt increase in the first patient preceded a transformation to a more acute phase by 2 months. We conclude that FISH analysis of PB cells of patients with MDS offers an additional approach to the study of clonality in this disorder. In some cases this analysis may provide a useful and simple means of assessing response to therapy and progression of disease.  相似文献   
75.
Shape response of human erythrocytes to altered cell pH   总被引:1,自引:0,他引:1  
Gedde  MM; Yang  E; Huestis  WH 《Blood》1995,86(4):1595-1599
Alteration of red blood cell (RBC) pH produces stomatocytosis (at low pH) and echinocytosis (at high pH). Cell shrinkage potentiates high pH echinocytosis, but shrinkage alone does not cause echinocytosis. Mechanisms for these shape changes have not been described. In this study, measured dependence of RBC shape on cell pH was nonlinear, with a broad pH range in which normal discoid shape was maintained. Transbilayer distribution of phosphatidylcholine and phosphatidylserine, measured by back-extraction of radiolabeled lipid, was the same in control and altered pH cells. Possible roles of pH- titratable inner monolayer phospholipids were examined by assessing pH- dependent shape in cells in which their levels had been perturbed. In metabolically depleted cells and calcium-treated cells, which have altered levels of phosphatidic acid, phosphatidylinositol-4-phosphate, and/or phosphatidylinositol-4,5-bisphosphate, low cell pH was stomatocytogenic and high cell pH was echinocytogenic, as in control cells. Thus, neither change in membrane lipid asymmetry nor normal levels of the pH-titratable inner monolayer lipids is necessary for cell pH-mediated shape change.  相似文献   
76.
77.
Objective: To investigate the effect of ultrasound in the treatment of osteoarthritis of the knee. Methods: Eighty‐seven out‐ and in‐patients with osteoarthritis of the knee (15 men and 72 women) underwent ultrasonic therapy from February to October 2010. The patients were randomly assigned to an ultrasound group (Group A) and a placebo group (Group B). Group A was offered ultrasonic therapy while Group B underwent mock treatment. The visual analogue scale (VAS) and Lequesne scores of the two groups before and after treatment were compared. The data were analyzed by normal distribution, Student's t‐test and the rank sum test. The means during and after treatment of the VAS and Lequesne efficacy index of the treatment group were calculated and plotted on a bar graph. Results: Single sample analysis of Groups A and B showed VAS efficacy index: mean = 0.3640, P= 0.000; Lequesne efficacy index, median = 0.3080, P= 0.000, and mean = 0.1000, P= 0.000; Lequesne efficacy index, mean = 0.0364, P= 0.024, respectively. Independent samples t test and rank sum test showed significant differences between the two groups, namely P= 0.000 for both the VAS and Lequesne curative effect indexes. The means of the VAS efficacy index of the treatment group increased during and after treatment. The means of the Lequesne efficacy index of the treatment group showed no apparent decrease by 28 days after treatment. Conclusion: Ultrasound treatment significantly alleviates joint symptoms, relieving joint swelling, increasing joint mobility and reducing inflammation, in osteoarthritis patients.  相似文献   
78.
Introduction: Based on early studies of non‐motor function in the cerebellum and dysfunction in the cerebellum of post‐traumatic stress disorder (PTSD) patients, we presumed that the cerebellum was involved in the neuropathology of cognitive and emotional processing of PTSD patients, while the density of some sub‐areas of the cerebellum of PTSD patients was most likely abnormal. Methods: Eleven female victims of rape with PTSD and 12 age‐matched female normal controls received 1.5 T 3D magnetic resonance imaging (MRI) scan. The scans were then analyzed using the voxel‐based morphometry 2 (VBM2) toolbox. Results: Victims of rape with PTSD showed increased cerebellum density on the left side compared with normal controls (P<0.001), especially in the pyramis (x=?9, y=?72, z=?36; k=519; t=4.70), uvula (x=?4, y=?66, z=?35; k=256; t=4.02), declive (x=?6, y=?69, z=?30; k=213; t=3.84) and nodule (x=?4, y=?63, z=?31; k=147; t=3.93). In addition, compared with normal controls, the PTSD group showed significant differences in gray matter density of other brain areas, including the frontal lobe, parietal lobe, occipital lobe (P<0.001), insula, posterior cingulate, amygdala and hippocampus (P<0.005). Discussion: These finding suggest that the cerebellum may be involved in the neuropathology and functional compensation in the neurocircuitry of PTSD.  相似文献   
79.
80.
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