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   1943篇
  免费   157篇
  国内免费   15篇
耳鼻咽喉   11篇
儿科学   53篇
妇产科学   25篇
基础医学   237篇
口腔科学   58篇
临床医学   162篇
内科学   601篇
皮肤病学   40篇
神经病学   190篇
特种医学   61篇
外科学   282篇
综合类   4篇
预防医学   45篇
眼科学   13篇
药学   117篇
中国医学   1篇
肿瘤学   215篇
  2024年   5篇
  2023年   42篇
  2022年   83篇
  2021年   141篇
  2020年   61篇
  2019年   101篇
  2018年   95篇
  2017年   85篇
  2016年   84篇
  2015年   91篇
  2014年   93篇
  2013年   111篇
  2012年   146篇
  2011年   143篇
  2010年   100篇
  2009年   62篇
  2008年   115篇
  2007年   104篇
  2006年   93篇
  2005年   72篇
  2004年   71篇
  2003年   61篇
  2002年   40篇
  2001年   11篇
  2000年   10篇
  1999年   21篇
  1998年   4篇
  1997年   11篇
  1996年   3篇
  1995年   1篇
  1994年   3篇
  1993年   3篇
  1992年   6篇
  1991年   6篇
  1990年   6篇
  1989年   4篇
  1988年   2篇
  1987年   5篇
  1986年   1篇
  1985年   4篇
  1984年   8篇
  1983年   1篇
  1981年   1篇
  1980年   1篇
  1979年   2篇
  1978年   1篇
  1974年   1篇
排序方式: 共有2115条查询结果,搜索用时 15 毫秒
991.
992.
993.

Purpose

The mass screening (MS) for neuroblastoma (NB) at 6 months of age in Japan was discontinued in 2004. This study assessed the risks and benefits of MS based on an analysis of NB detected before or after discontinuation of MS in Japan.

Methods

The clinical features and Brodeur's genetic type based on MYCN, DNA ploidy, and other genetic aberrations were assessed in 113 NB patients (20 cases after and 93 cases [55 MS cases] before the discontinuation of MS) older than 6 months treated at one institution since 1985.

Results

The 20 patients with NBs detected after MS was discontinued ranged in age from 7 to 67 months, 12 patients were stage 4, and 11 patients would have been detected at 6 months of age if they had undergone MS. The Brodeur's genetic type of these 20 patients showed that 30% (6/20) were type 1 (low risk), 55% (11/20) were type 2A (intermediate risk), and 15% (3/20) were type 2B (high risk). Of 93 patients with NB detected before MS was discontinued, 60% (56/93) were type 1, 18% (17/93) were type 2A, and 22% (20/93) were type 2B. Among the type 2A patients, 82% (9/11) of the patients detected after MS was discontinued showed stage 4, whereas only 50% (9/18) of those diagnosed before MS was discontinued were stage 4. The genetic analysis using single nucleotide polymorphism (SNP) array for type 2A showed that the pattern of genetic aberration was equivalent in those detected either before or after MS was discontinued.

Conclusions

There was a decrease of type 1 and an increase of type 2A NB in patients after MS was discontinued in Japan. These results suggest that most of the type 1 detected by MS has regressed, and most of the type 2A detected by MS has appeared sporadically as advanced NB in patients older than 1 year.  相似文献   
994.
Intense FDG uptake in the ovary with painless torsion   总被引:1,自引:0,他引:1  
We report a case demonstrating intense FDG uptake in the ovary, which was diagnosed to be a hemorrhage and congestion due to painless torsion. An asymptomatic retropelvic mass was detected in a 51-year-old female by echography. FDG-PET demonstrated intense uptake in the mass, thus suggesting an ovarian tumor. A resection of the tumor was performed, and histopathological examination revealed hemorrhage and congestion in the ovary due to ovarian torsion. An ovarian hemorrhage due to painless torsion should be considered in the differential diagnosis of intrapelvic masses demonstrating high FDG uptake, even in asymptomatic patients.  相似文献   
995.
996.
Background Platelets contain several growth factors, including platelet-derived growth factor and hepatocyte growth factor. Materials and methods We examined the effects of platelet increment on liver regeneration after 70% hepatectomy. Hepatectomies were carried out in male BALB/c mice, and subsequently divided into three groups: (i) untreated mice, (ii) thrombocytotic mice induced with thrombopoietin, and (iii) thrombocytopenic mice induced with anti-platelet antibody. Growth kinetics in the liver were analyzed as a function of the liver/body weight ratio, the mitotic index, the proliferating cell nuclear antigen labeling index and Ki-67 labeling index. Activation of signal transduction pathways relating to cell proliferation were examined, including the STAT3, Akt, and ERK1/2 pathways. Platelet accumulation in the residual liver was quantified by immunohistochemistry and transmission electron microscopy. Results In thrombocytotic and thrombocytopenic mice, liver/body weight ratios and Ki-67 labeling indices were significantly increased and significantly decreased, respectively, compared with untreated mice 48 hours post-hepatectomy. The Akt pathway was strongly activated, and platelet accumulation was significantly increased in thrombocytotic group 5 minutes post-hepatectomy compared with normal and thrombocytopenic groups. After hepatectomy platelets accumulated in the sinusoids of liver and promoted hepatocyte proliferation in early period after hepatectomy. Conclusion By increasing or decreasing the platelet, marked changes in liver regeneration can occur, due to differences in cellular signaling and mitosis.  相似文献   
997.
We examined the clinical evaluation of biapenem (BIPM) for febrile neutropenia in patients with hematological disorders. BIPM was administrated by drip infusion when fever developed over 37.5 degrees C with a neutrophil counts lower than 1000/microl. The underlying diseases were acute myelogenous leukemia in 16 cases, acute lymphocytic leukemia in 1, malignant lymphoma in 14, myelodysplastic syndrome in 1, aplastic anemia in 1. Microbiologically documented infections were found in 3 cases (9.1%) before treatment. Clinical effect was excellent in 9 cases, good in 11, fair in 6, poor in 7. Factors associated with efficacy rate were concomitant use of granulocytecolony stimulating factor, duration of neutropenia and neutrophil counts at day 3 of day after start of the therapy. No serious adverse events were observed in all cases, although one case developed exanthema. In conclusion, these results confirmed the efficacy and safety of BIPM for febrile neutropenia in patients with hematological disorders.  相似文献   
998.
Cysteinyl-leukotrienes (cysLTs) and thromboxane A2 (TXA2) are important mediators in inflammatory lung diseases such as bronchial asthma and idiopathic pulmonary fibrosis (IPF). We examined the effects of inhaled KP-496, a novel dual antagonist of the cysLTs and TXA2 receptors, on bleomycin-induced IPF in mice. Mice were intravenously injected bleomycin on day 0, and 0.5% of KP-496 was inhaled twice a day (30 min/time) for the entire experimental period. The effects of KP-496 were evaluated by the number of infiltrated cells in bronchoalveolar lavage fluid (BALF), hydroxyl-l-proline content in the lung, and histopathology. Analyses of BALF on days 7 and 21 revealed that inhaled KP-496 significantly decreased total cell numbers, macrophages, neutrophils, and eosinophils on both days. KP-496 significantly decreased hydroxyl-l-proline content in the lung on day 21. Histopathological analyses of lungs on day 21 demonstrated that KP-496 significantly suppressed inflammatory and fibrotic changes. Our results suggested that the suppression of cysLTs and TXA2 pathways by KP-496 could control airway inflammation and pulmonary fibrosis, and that KP-496 could be a new therapeutic agent for lung diseases with inflammation and fibrogenesis such as IPF and chronic obstructive pulmonary disease.  相似文献   
999.
We performed the genotyping and phylogenetic analysis of respiratory syncytial virus (RSV) isolated from 17 infants with bronchiolitis in Kanagawa Prefecture, Japan in 2005 and 2006. The major genes in these samples (attachment [G] glycoprotein gene, fusion [F] protein gene, and nucleoprotein [N] gene) were sequenced and analyzed genetically. Phylogenetic analysis of these genes revealed that 7 and 10 strains could be classified into subgroups A and B, respectively. Phylogenetic analysis of the G gene revealed that the subgroup A and B strains were unique genotypes GA2 and BA, respectively. Moreover, the amino acid sequences for these genotypes suggested a relatively high frequency of amino acid substitutions in the G and F proteins in these strains, whereas the N protein was highly homologous. These results suggest that RSV genotypes GA2 and BA may be associated with bronchiolitis in the cases studied here.  相似文献   
1000.
We report here a rare case of insufficiency fracture at the distal diaphysis of the radius in a patient with rheumatoid arthritis (RA) after synovectomy combined with the Sauvé-Kapandji procedure. A 71-year-old woman who had been diagnosed with RA had been consecutively treated with several disease-modifying antirheumatic drugs. She had undergone synovectomy of the right wrist combined with the Sauvé-Kapandji procedure, due to a tendon rupture, 2 years before the current presentation (first visit). Although she had not experienced any recent trauma, the wrist pain had increased after she had lifted up the bedding at the funeral of her friend about 1 month prior to her first visit. Radiographs of her right wrist taken at the second visit showed a fracture at the distal diaphysis of the radius at the level of the excision osteotomy of the distal ulna; however, no displacement of the distal fragment was observed. We immobilized her forearm in a long-arm cast. However, after 3 weeks of cast immobilization, a displacement of the distal fragment was observed. A manual reduction of the displacement was performed and the arm was again immobilized in a long-arm cast. However, 1 week later, a displaced distal fragment was again observed. Subsequently, she received an open reduction and internal fixation using a volar locking plate and screws with an autologous iliac crest bone graft. Bone union was completed by 8 months following the operation.  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