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BACKGROUND: Apoptotic cell death plays a key role in the pathogenesis, aggressiveness, and therapy responsiveness of cancer. The suicidal machinery of apoptosis is genetically controlled. Proteins of the Bcl-2 family as well as p53 are important regulators of apoptosis. OBJECTIVE: To assess the rate of spontaneous apoptosis and the expression of p53 and Bcl-2 family proteins in locally advanced squamous cell carcinomas of the head and neck. DESIGN: Twenty-six patients with locally advanced squamous cell carcinoma of the head and neck were included in the study. The expression of p53, Bcl-2, Mcl-1, Bax, and Bak was assessed by immunohistochemical analysis. The terminal deoxytransferase-mediated deoxyuridine nick end-labeling assay was used to quantify apoptosis by flow cytometry. RESULTS: Tumor cells containing immunostaining for the antiapoptotic proteins Bcl-2 and Mcl-1 were present in 4 (15%) and 24 (92%) of the cases evaluated, respectively, whereas immunopositivity for the proapoptotic proteins Bax and Bak was found in 9 (35%) and 24 (92%) of the samples. Immunoreactivity to p53 was detected in 20 (77%) of the samples. There was a positive correlation between the expression of Bcl-2 and Bax and between Mcl-1 and Bak. A low fraction of apoptotic cells (<2.5%) in the pretreatment tumor samples was significantly correlated with increased 2-year survival in these patients. CONCLUSIONS: Our results establish the frequent expression of the Bcl-2 family proteins Bcl-2, Mcl-1, Bax, and Bak in locally advanced head and neck cancer. In addition, this study suggests that the apoptotic fraction in pretreatment tumor samples might be of prognostic importance for the outcome in these patients.  相似文献   
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OBJECTIVE: In 1983 Vigorita reported 3 cases of osteoporosis associated with intramedullary lymphoid nodules. We present 8 patients with osteoporosis and lymphoid nodules (LN) in whom we studied the clinical, biological and histological features and the course of the disease. METHODS: Three men (mean age 52 yrs., range 43-68 yrs.) and 5 women (mean age 60 yrs., 49-66 yrs.), 6 of them with osteoporosis with fracture and 2 with osteoporosis on bone densitometry (T score < -2.5 SD) were enrolled in this study. The following parameters were studied: immunobinding with IG determination, phosphorus and calcium levels, PTH, 25 and 1-25 OH D3, osteocalcin, urinary deoxypyridinoline, histomorphometry, tests for autoanti-bodies, HIV, HTLV, EBV and CMV serology. The results were compared with those of 20 patients with osteoporosis but without LN. Five patients underwent a second BMB a mean of 2 years after the first. RESULTS: Five patients had asthenia, 4 had joint pain and 3 had hyperlymphocytosis. Immunologic and virologic investigations were negative in all cases. Bone marrow was hypercellular (59.9 +/- 5.3 vs 40.1 +/- 13%, p: 0.001). At the second BMB, LN were absent but bone marrow was still hypercellular. In all cases, no cause of demineralization was found and osteoporosis progressed rapidly (an average of 3 vertebral compression fractures in three months, with increased resorption (ES 6.5 +/- 1.6 vs 3 +/- 1.2, p: 0.05) with decreased calcification rate (CR 0.62 +/- 0.07 vs 0.79 +/- 0.1, p: 0.04). CONCLUSION: Some interesting questions are raised by this study. Did an undiscovered viral infection cause the asthenia and joint pain via cytokines or PTHrp in our patients, and can activated lymphocytes perhaps modify bone remodeling?  相似文献   
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Sixteen cases of primary anterior mediastinal B-cell lymphoma were characterized by morphologic, immunophenotypic, and clinical profiles. Twelve were men and four were women. The median age was 42 years. Virtually all tumors were of large cell type. Three main morphologic categories were identified, with one rare exception. In some tumors, the cells were compatible with centrocytes and centroblasts (four). Others had cells readily identifiable as centroblasts (six). Both these groups had a variable proportion of cells with multilobed nuclei. A third group was composed mainly of unclassifiable cells with multilobed nuclei (five). All had discernible sclerosis of varying intensity. A wider range of morphologic features and different sex distribution was noticed in comparison with previously reported clear cell features and younger women. The dominant phenotype of these B-cell lymphomas was CD19+, CD22+, CD37+, CD21-, CD30-, CD10-, CD5-, and Ig-negative. The finding of CD21-, Ig-negative phenotype, as observed by the authors and others, overlaps with some high-grade lymphomas of follicular center cell origin but is thought to bear similarity to a noncirculating population of thymic medullary B-cells. The tumors attained large size without peripheral dissemination and responded to chemotherapy as well as radiotherapy.  相似文献   
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In order to study the distribution of lymphocyte subpopulations in a pathologic intestinal mucosa, the authors, instead of using the classic method by counting the number of lymphocytes, present an original method permitting the exploitation of quantified data from labelled surface cells by texture analyser coupled with a computerized system. We investigated 25 children presenting with chronic diarrhea and villous atrophy and 5 control subjects. Fifteen of the 25 children had celiac disease (10 active with total villous atrophy and 5, celiac disease in remission with healing mucosa), 5 cow's milk protein intolerance with total or partial villous atrophy and 5, chronic diarrhea with partial villous atrophy. Immunohistochemical study with monoclonal antibodies was carried out on frozen sections using a three-step immunoperoxidase technique. Compared with the 5 controls, patients with food intolerance (celiac disease and cow's milk protein intolerance) showed a significant increase of T suppressor lymphocytes (p less than 0.01 and p less than 0.05) in the epithelium, whereas there were more T helper lymphocytes in the lamina propria (p less than 0.05 and p less than 0.01). Non-treated celiac disease was distinguished from treated celiac disease by a marked increase in intra-epithelial T cytotoxic-suppressors. These results suggest that T cytotoxic-suppressors may be the mediators of the lesions observed in celiac disease.  相似文献   
25.
BackgroundNo biological or molecular marker of primary melanoma tumor cells has been shown to predict clinical outcome in melanoma.ObjectiveTo determine whether CD10, CD133, nestin and CD20 may evaluate the prognosis of melanoma.MethodsThe differential expression of these molecules was assessed in pairs of cell lines. We evaluated, by both immunohistochemical staining and RT-qPCR, their expression in a cohort of 32 patients (68 samples) with a history of metastatic melanoma, divided into two groups according to their clinical outcome profile.ResultsCD10 over expression in cancer cell lines was associated with more aggressive behavior in vitro. A CD10-positive staining was more frequent in patients in the “rapidly progressive” group than those in the “long survivor” group (23/35 versus 2/18, p < 10?4). CD10 expression was associated with a lower median overall survival (1.15 year – IQR: [0.50–2.58] versus 4.27 – IQR: [1.66–6.33]; p = 10?4). The Odds Ratio of displaying a “rapidly progressive” melanoma when tumor cells expressed CD10 was 15 (95% confidence interval: [3–78]). After adjusting for confounding factors, CD10 expression in melanoma tumor cells remained associated with an increased risk of death and more rapid disease progression (p = 6 × 10?4; HR = 3.71).ConclusionCD10 may predict clinical outcome in melanoma patients.  相似文献   
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