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21.
Prophylactic oophorectomy: a morphologic and immunohistochemical study   总被引:2,自引:0,他引:2  
BACKGROUND: The tumorigenesis of ovarian carcinoma is poorly understood. The authors studied morphologic features and immunohistochemical expression patterns of neoplasia-associated markers in prophylactically removed ovaries, normal ovaries, and papillary serous ovarian carcinomas to identify possible preneoplastic changes in ovarian surface epithelium. METHODS: Morphologic features and immunohistochemical expression patterns of CA-125, Ki-67, p53, E-cadherin, and Bcl-2 were evaluated in 21 normal ovaries, 31 ovaries that were removed prophylactically for increased carcinoma risk, and 7 ovarian papillary serous carcinomas. Representative slides from formalin-fixed, paraffin-embedded tissue blocks were submitted to immunohistochemical staining and were evaluated independently by three gynecologic pathologists. For statistical analyses, Fisher exact tests, multivariate analyses, Spearman rank correlation coefficients, Wald statistics, Kruskal-Wallis tests, and Mann-Whitney tests were used. Immunohistochemical staining results were correlated with morphologic findings. RESULTS: The authors found progressive increases in reactivity with the lowest expression in normal ovarian epithelium, stronger expression in epithelium from prophylactically removed ovaries, and the highest expression in carcinomas for Ki-67 and p53. A similar trend was observed for CA-125. Positivity for Ki-67 and p53 was seen predominantly in the epithelium of inclusion cysts and deep invaginations, including those areas that had been identified as hyperplastic or dysplastic on routine hematoxylin and eosin-stained sections. CONCLUSIONS: The current results suggest biologic/molecular evidence for the existence of preneoplastic changes in ovarian surface epithelium and support the previously proposed concept of ovarian dysplasia. Subtle morphologic alterations of the ovarian epithelium may be biologically significant.  相似文献   
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High frequencies of loss of heterozygosity (LOH) in chromosome 11q22-qter have been observed in various malignancies, including breast cancer. Previous studies on breast carcinomas by Winqvist et al (Cancer Res 55: 2660-2664) have indicated that a survival factor gene is located in band 11q23, and that the highly informative microsatellite polymorphism at the APOC3 locus would be a suitable tool to perform more extensive LOH studies. In this European multicentre study, we have examined the occurrence of APOC3 LOH and evaluated the effect of LOH of this chromosomal subregion on the clinical behaviour of the disease in a cohort of 766 breast cancer patients in more detail. LOH for APOC3 was found in 42% of the studied tumours, but it was not found to be significantly associated with any of the studied clinical variables, including cancer-specific survival time or survival time after recurrent/metastatic disease. According to the present findings, the putative survival factor gene on 11q23 is not located close enough to the APOC3 gene, but apparently at a more proximal location.  相似文献   
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OBJECTIVES: Firstly to evaluate future mortality from mesothelioma in France with an age-period-cohort approach and evaluate different hypotheses on risk of mesothelioma for the most recent birth cohort. Secondly to compare the results with a British and an American study. Thirdly to study if any trends were detectable on data for women which would be consistent with the consequences of increasing environmental exposure to asbestos. METHODS: Estimates of mortality from mesothelioma among men and women in France from 1950 to 1995 were based on the analysis of the pleural cancer mortality data coded 163 in the ninth revision of the international classification of diseases (ICD-9). Correction factors were used to derive the mortality from mesothelioma from these data, based on two regional registries. The analysis of the past mortality data has been performed by an age-cohort model (with a maximum likelihood technique). Predictions of deaths from mesothelioma over the next 50 years were based on four different assumptions on the risk of death from mesothelioma in future birth cohorts. RESULTS: The predicted lifetime probability of dying from mesothelioma increases until the last birth cohort 1964-8 among men whereas it decreases strongly from the 1954-8 birth cohort among women. The projected numbers of deaths from mesothelioma in France until 2020 are similar, whichever hypothesis is considered: around 20,000 deaths from mesothelioma might occur among men and 2900 among women from 1996 to 2020. CONCLUSIONS: French data show an increasing lifetime probability of death from mesothelioma in the more recent male cohorts. Although the mortality burden can be predicted until 2020, and is intermediate between the United Kingdom and United States estimates, there is still high uncertainty on the figures after 2020. No increase is found in women, and this does not support the hypothesis that current environmental exposure to asbestos could be associated with a detectable risk of death. Specific surveillance should be set up to monitor future trends or their absence.    相似文献   
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Previous studies using Southern blot analysis or in situ hybridization have shown that approximately 20% of patients with Hodgkin's disease have Epstein-Barr virus (EBV) in involved tissues. We used the more sensitive polymerase chain reaction (PCR) technique to determine if a higher percentage of EBV could be detected. Of the 16 Hodgkin's disease patients studied, the PCR technique detected EBV in eight (50%). No prognostic significance was associated with the presence of EBV in the eight EBV-positive patients, and the presence of EBV was not associated with B cell monoclonality.  相似文献   
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The antigen receptor genes studied (immunoglobulin gene for B-cells, and T-cell receptor -beta or -gamma gene for T-cells) represent the most powerful tools for diagnosing the clonality of a lymphoid lineage. We have clonotyped 23 cutaneous T-cell lymphomas and 5 were found to be clonotypically all heterogeneous. Analysis of each patient was performed either from serial skin biopsies taken several months apart or from different tumor samples. In these cases, T-cell lymphoma clonotypic heterogeneity was demonstrated and was especially evident when examining different tumor sites. Moreover, in one case, a biogenotypic population (immunoglobulin and T-cell receptor-rearranged) was found. This unexpected high frequency of T-cell clonal heterogeneity (22%) could be explained either by the evolution of subclones from a single undifferentiated malignant cell or by the independent transformation to cancer of 2 or more lymphocytes, though the latter seems less likely. Clonotypic heterogeneity seems to be as frequent in T-cell lymphomas with cutaneous lesions as in B-cell leukemias.  相似文献   
28.
To evaluate the prevalence of inherited respiratory ciliary structure and underlying mucus abnormalities in the diffuse bronchiectasis syndrome, we investigated 53 subjects comprising 38 patients with diffuse bronchiectasis confirmed by high-resolution thoracic computed tomography, ten with chronic bronchitis and no diffuse bronchiectasis and five healthy nonsmoking control subjects. The clinical history was determined by means of a standardized questionnaire. Axonemal abnormalities of respiratory cilia were evaluated on bronchial or nasal mucosa samples by transmission electron microscopy (structure) and stroboscopic observation (function). Cystic fibrosis (CF) and Young's syndrome were detected by means of the sweat test and semen analysis when male infertility was suspected. Among the 38 patients with diffuse bronchiectasis, a primary ciliary dyskinesia (PCD) was detected in five (13%) with a high proportion (range: 55-100%) of cilia showing axonemal ultrastructural abnormalities always involving the dynein arms. The prevalence of this inherited condition was higher in North African (36%) than in European patients (4%) (p less than 0.01). After exclusion of the five patients with PCD, the patients with diffuse bronchiectasis showed axonemal ultrastructural abnormalities similar to those with chronic bronchitis. The diagnosis of underlying mucus disorders was based on two types of criterion, i.e. for CF, sweat chloride levels greater than 80 mmol.l-1, or the combination of diagnostic criteria proposed by Stern et al. Respectively, five (three Young's syndrome and two CF) and seven (one Young's syndrome and six CF) cases of inherited mucus disorders were suspected. Our results showed that PCD was highly prevalent among the adult North African patients with diffuse bronchiectasis but relatively rare in the Europeans.  相似文献   
29.
The authors report the immunogenotype of two cases of Richter's syndrome. The immunoglobulin gene rearrangement pattern obtained on Southern Blot analysis was found in both cases to be the same in leukemic blood cells and in the tissue involved by the lymphoma. The beta chain and gamma chain T-cell receptor gene rearrangement pattern exhibited a germ-line configuration in the peripheral blood cells and in the lymph node in Case 2, whereas in Case 1 the lymph node had a gene rearrangement in the beta chain, as well as in the gamma chain T-cell receptor, and the leukemic cells from bone marrow were found to be in a germ-line configuration for T-cell receptors (beta and gamma chains).  相似文献   
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