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   230篇
  免费   6篇
  国内免费   1篇
耳鼻咽喉   3篇
儿科学   38篇
妇产科学   9篇
基础医学   10篇
口腔科学   15篇
临床医学   12篇
内科学   50篇
皮肤病学   10篇
神经病学   4篇
特种医学   14篇
外科学   34篇
综合类   3篇
预防医学   11篇
眼科学   5篇
药学   13篇
中国医学   1篇
肿瘤学   5篇
  2023年   1篇
  2021年   3篇
  2020年   2篇
  2019年   2篇
  2018年   4篇
  2017年   4篇
  2016年   6篇
  2015年   8篇
  2014年   3篇
  2013年   8篇
  2012年   16篇
  2011年   15篇
  2010年   16篇
  2009年   5篇
  2008年   12篇
  2007年   17篇
  2006年   18篇
  2005年   15篇
  2004年   16篇
  2003年   17篇
  2002年   23篇
  2001年   10篇
  2000年   7篇
  1999年   8篇
  1990年   1篇
排序方式: 共有237条查询结果,搜索用时 15 毫秒
1.
Nanobacteria: an infectious cause for kidney stone formation   总被引:23,自引:0,他引:23  
BACKGROUND: Nanobacteria are cytotoxic, sterile-filterable, gram-negative, atypical bacteria detected in bovine and human blood. Nanobacteria produce carbonate apatite on their cell walls. Data on Randall's plaques suggest that apatite may initiate kidney stone formation. We assessed nanobacteria in 72 consecutively collected kidney stones from Finnish patients. METHODS: Nanobacteria and kidney stone units were compared using scanning electron microscopy (SEM). Demineralized kidney stones were screened for nanobacteria using a double-staining method and a specific culture method. Isolated nanobacteria were analyzed for mineral formation in vitro with Ca and 85Sr incorporation tests. RESULTS: SEM highlighted the resemblance in size and morphology of nanobacteria and the smallest apatite units in the kidney stones. Nanobacterial antigens could be detected after the demineralization of the stones in 1 N HCl. Nanobacteria were surprisingly resistant to this treatment, and cultures could be established from 93.1% of the stones. Only struvite stones had common bacteria, in addition to the nanobacteria. When the results of all of the assays were combined, 70 of the 72 stones (that is, 97.2%) were nanobacteria positive. Although apatite stones indicated highest nanobacteria antigen signals, the overall nanobacteria positivity did not depend on the stone type. The isolated nanobacteria produced apatite stones in vitro, measured by Ca and 85Sr incorporation. CONCLUSIONS: We propose that kidney stone formation is a nanobacterial disease analogous to Helicobacter pylori infection and peptic ulcer disease. Both diseases are initiated by bacterial infection and subsequently endogenous and dietary factors influence their progression.  相似文献   
2.
Several studies indicate that thrombosis plays an important role in the pathogenesis of coronary heart disease (CHD). Fibronectin is a multifunctional protein in plasma, other body fluids, and cell surface and plays an important role in platelet functions, including mediation of cell-cell and cell-surface interactions. Sialic acid is a regular constituent of glycoproteins and gangliozides in the outer cell membrane of mammalian cells. Therefore, the sialic acid content of platelets, which are characterized by their ability to aggregate with each other, can be important in leading to thrombus formation. In this study, platelet fibronectin, sialic acid-, and adenosine diphosphate (ADP)-induced platelet aggregation levels were determined in patients with CHD. Platelet sialic acid concentrations were determined by Warren's method. Platelet aggregation tests with ADP in platelet-rich plasma (PRP) were analyzed by use of an aggregometer. Platelet homogenate fibronectin levels were determined by ELISA. Total protein levels were determined by Lowry method. Our results indicate that, in patients with no vessel disease (patients with no obstructed vessel but suffering from chest pain, like angina pectoris) platelet fibronectin levels were significantly lower than the total of the other patients (patients with 1, 2, or 3 obstructed coronary vessels) (p<0.05). Sialic acid levels in patients with no vessel disease were significantly lower than the total of the patient group (p<0.05). There was significant (+) correlation between platelet aggregation, platelet fibronectin, platelet sialic acid, and severity of disease (p<0.05). Our preliminary findings suggest that, especially platelet fibronectin levels potentially represent a pathogenic factor for CHD.  相似文献   
3.
Methotrexate (MTX) remains one of the most frequently used anti-metabolite agents in dermatology. MTX is an analog of folate that competitively and irreversibly inhibits dihydrofolate reductase. Oral mucositis is a common side effect of chemotherapy drugs and is characterized by erythema, pain, poor oral intake, pseudomembranous destruction, open ulceration and hemorrhage of the oral mucosa. In this paper, we report a 32-year-old female with a case of mucositis due to MTX intoxication that resulted from an overdose for rheumatoid arthritis. The patient had abdominal pain, vomiting, and nausea. During follow-up, the patient’s white blood cell count was found to be 0.9?×?109/L (4–10?×?109/L). The patient developed fever exceeding 40?°C. The patient was consulted to the hematology service. They suggested using granulocyte colony-stimulating factor for febrile neutropenia. On the fifth day of treatment, the white blood cell count reached 5.3?×?109/L and the patient’s fever and mucositis started to resolve. Here, we presented a case of hemorrhagic mucositis and febrile neutropenia resulted from high-dose MTX that responded very well to granulocyte colony-stimulating factor treatment and we reviewed the literature.  相似文献   
4.
5.
6.
To investigate the reason of high incidence of annual patients with tuberculosis (TB) in a military school previously known by screening tuberculin skin test (TST) and finding out the proportion of annual infection risk (PAIR), the prevalance of TB infection and the distribution for each grades. Our study is a cross-sectional epidemiologic study made about TB infection. TST were screened for all students in the school. 5 TU PPD was injected to every student and after 72 hours, the results were evaluated by measuring the diameter of enduration. Test was repeated after 10 days for negative reactions. Age, sex, the number of BCG wound, smoking and dwelling for last 5 years were asked from the students and their answers were recorded. More than 10 mm enduration for cases who had no BCG and 15 mm enduration for cases who had BCG were accepted positive. Chest roentgenogram was taken for each student enrolled into the study. Infection prevalance and PAIR were calculated after tests and measurements. The total number of students was 948. Of 917 (96.7%) were male and 31 (3.3%) were female. The mean age was 19.72 +/- 1.25. The mean of TST was 12.79 +/- 5.96 mm for all students. According to the number of BCG scar, the numbers of students, percentage and the mean of TST were like that 70 (7.3%) cases no BCG scar 8.41 +/- 7.87 mm, 393 (41.4%) students one BCG scar, 11.94 +/- 6.26 mm, 343 (36.1%) cases two BCG scars, 13.74 +/- 5.12 mm, 142 (14.9%) students three or more then three scars, 14.97 +/- 4.11 mm. In the students who had no BCG, TST positivity was 50%. TB infection prevalance of entire school and PAIR were 46% and 3.44% (respectively). In this study, we found that increased number of BCG wound associated with the increased diameter of TST enduration. The proportion of unvaccinated students was similar to the same age population in our country but it showed differences in the distribution of regions. The students who started first grade had serious TB infection risk in their first school year. We think that PAIR values derived from TST conversions done in high risky community by screening annual TST could show all aspects of TB infection risk in those community.  相似文献   
7.
The study investigated in vitro effects of halothane, isoflurane, ketamine, sevoflurane, prilocaine, diazepam, and midazolam on enzymatic activity of human red blood cell glucose-6-phosphate dehydrogenase (G6PD; E.C. 1.1.1.49). G6PD was purified from human red blood cells by 2',5'-ADP-sepharose 4B affinity gel. Enzymatic activity was spectrophotometrically measured at 340 nm according to the method of Beutler. I50 values were determined from drug activity (%) - drug concentration curves. I50 values were as follows: 0.72 mM for isoflurane, 1.82 mM for sevoflurane, 0.38 mM for diazepam, and 0.0019 mM for midazolam. But halothane, ketamine and prilocaine had no inhibitory effect on the G6PD activity in in vitro.  相似文献   
8.
9.
Netherton syndrome is a rare genodermatosis comprised of anichthyosiform dermatitis, hair shaft defects, and atopic features. Other problems associated with Netherton syndrome are delayed growth and development, immune abnormalities, recurrent infections, and intermittent aminoaciduria. We describe an 18-month-old girl with Netherton syndrome who had idiopathic congenital hemihypertrophy on her right side with contralateral benign nephromegaly in addition to the characteristic clinical signs of the syndrome. To our knowledge, this is the first case of Netherton syndrome associated with idiopathic congenital hemihypertrophy to be reported.  相似文献   
10.
Thymic masses constitute one of the least common mediastinal masses in childhood. While producing symptoms of airway compromise, they also raise the suspicion of malignancy when detected. Radiological, operative and pathological findings of patients that have been operated for thymic masses in our institution is presented in this paper. Nine patients were operated in our institution during a 12-year-period between 1985-1997 for thymic masses. Ages of the patients ranged from four months to 13 years. With the exception of one, who was diagnosed with a routine chest x-ray, all the patients had respiratory complaints. All the patients had been evaluated with computed tomography preoperatively. In total, seven sternotomies and four thoracotomies were performed to reach the anterior mediastinum. The distribution of masses was as follows two malignant thymomas, three thymic hyperplasia, one lymphocyte-rich thymoma, one epithelial thymoma, one cystic thymoma and one lymphoblastic lymphoma. Although rare, thymic enlargement may be a cause of intractable respiratory complaints in childhood. Because of the high incidence of primary malignancy of the mediastinal neoplasms in childhood, thymic enlargement requires accurate pathological diagnosis and treatment. Median sternotomy with intensive anesthetical care allows proper tumoral exposure.  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