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1.
Using an in vitro system, the growth characteristics and enzyme histochemical properties of 3 odontogenic keratocysts and 3 dentigerous cysts were studied. It was found that the epithelial cells of the keratocysts hut not of the dentigerous cysts grew in vitro. Furthermore, the epithelial-like cells of the keratocysts showed the same activities of acid phosphatase and NADH-diaphorase in vitro as earlier described in vivo. These enzymatic activities were increased in epithelial-like cells close to proliferating fibroblast-like cells, indicating a close relationship between these two cell types. The results are discussed in the light of the known clinical behaviour of the keratocysts and certain conclusions are also drawn concerning the suggested neo plastic potential of the keratocysts.  相似文献   
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Clearcell sarcoma is a rare soft tissue sarcoma that displays certain similarities to malignant melanoma. In this paper we describe the karyotypic findings and in vitro growth characteristics of a shorttermcultured clearcell sarcoma. The cultured tumor cells had preserved immunohistochemical characteristics and certain ultrastructural features of the primary tumor, including positivity for vimentin, S-100 protein, and a melanomaassociated antigen, supporting the authenticity of the cultured cells. Cytogenetic analysis revealed an abnormal stemline karyotype of 49,XY, –1, + 8, + 8, + 12, + der(l)t(1;?)(p36.1 –.3;?), t(12,22)(q13;q13). A similar or identical t(12;22) was recently reported in two of four clear-cell sarcomas. It is suggested that the t(12;22)(q13;q13) is a primary cytogenetic abnormality in clear-cell sarcoma and distinguishes this tumor type from malignant melanoma.  相似文献   
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AIMS: The tumour-associated trypsin inhibitor (TATI) is a 6-kDa protease inhibitor with potential inhibitory effects on tissue degradation. In serum, increased levels have been associated with adverse prognosis in different forms of cancer. We assessed the tumour tissue expression and prognostic value of TATI in a surgically treated, single-institution series of patients with gastric cancer. METHODS AND RESULTS: Using a monoclonal anti-TATI antibody, immunohistochemistry was performed on formalin-fixed paraffin-embedded tumour specimens from 336 patients. TATI expression was observed in 265 (79%) of the tumours. There was a significant association between high TATI expression and low stage (P = 0.007), superficial tumours (P = 0.005), and absence of nodal (P = 0.015) and of distant metastases (P = 0.022). In univariate analysis, patients with high TATI expression had a significantly more favourable 5-year cumulative survival compared with patients with negative to moderate immunostaining (43% and 28%, respectively, P = 0.006). On multivariate survival analysis stratified for estimated cure of surgery, stage (P < 0.0001) and age (P = 0.022) at the time of surgery were independent prognostic factors. CONCLUSIONS: High TATI expression in tumour tissue was detected more frequently in patients with early-stage gastric cancer and seems to correlate with a favourable outcome.  相似文献   
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We studied the dynamics of serum human chorionic gonadotrophin(HCG) and its free (HCG) and (HCGP) subunits in 49 early pregnanciesachieved by in-vitro fertilization (IVF) and embryo transfer.Of the 49 early pregnancies, nine were normal singleton pregnancies,11 were twin pregnancies, 11 were ectopic, eight ended in aclinical (spontaneous) abortion and 10 ended in a preclinicalabortion. The HCG, HCGa and HCGP concentrations in serum weremeasured on days 12, 19 and 26 after embryo transfer. Most ectopicpregnancies could be distinguished from singleton (and twin)pregnancies on the basis of low HCG concentrations by 12 daysafter embryo transfer, but clinical abortions could not be distinguishedfrom singleton pregnancies. In general, the measurement of HCGaand HCG and the molar ratios of the various forms provided onlymarginal additional value to that obtained from HCG, but ondays 19 and 26 after embryo transfer HCGa was the most sensitiveindicator of a normal pregnancy after IVF and embryo transfer.We conclude that in ectopic pregnancies the concentrations ofHCG, HCGa and HCGP increase as expected but 1.5 days later thanin normal pregnancies. This appears to be the result of a delayin implantation.  相似文献   
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PURPOSE: The discovery of new ovarian cancer biomarkers that are suitable for early disease diagnosis and prognosis may ultimately lead to improved patient management and outcomes. PATIENTS AND METHODS: We measured, by immunoassay, human kallikrein 6 (hK6) concentration in serum of 97 apparently healthy women, 141 women with benign abdominal diseases, and 146 women with histologically proven primary ovarian carcinoma. We then calculated the diagnostic sensitivity and specificity of this test and examined the association of serum hK6 concentration with various clinicopathologic variables and patient survival. RESULTS: Serum hK6 concentration between normal and benign disease patients was not different (mean, 2.9 and 3.1 micro g/L, respectively). However, hK6 in presurgical serum of ovarian cancer patients was highly elevated (mean, 6.8 micro g/L; P <.001). Serum hK6 decreased after surgery (to a mean of 3.9 micro g/L) in 68% of patients. The diagnostic sensitivity of serum hK6 at 90% and 95% specificity is 52% and 47%, respectively, in the whole patient population. For early stage disease (stage I or II), sensitivity is approximately 21% to 26%. When combined with CA-125, at 90% specificity, sensitivity increases to 72% (for all patients) and to 42% in stage I or II disease. Serum hK6 concentration correlates moderately with CA-125 and is higher in patients with late-stage, higher-grade disease and in patients with serous histotype. Preoperative serum hK6 concentration is a powerful predictor of disease-free and overall survival in both univariate and multivariate analyses. CONCLUSIONS: Serum hK6 concentration seems to be a new biomarker for ovarian carcinoma and may have value for disease diagnosis and prognosis.  相似文献   
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Objective To evaluate the use of the pre-operative tumour-associated trypsin inhibitor (TATI) level and residual tumour size at primary surgery as a prognostic indicators for patients with Stage III epithelial ovarian cancer.
Design Retrospective cohort study.
Setting Department of Obstetrics and Gynaecology, University Hospital, Helsinki, Finland.
Participants Ninety-eight women with Stage III ovarian cancer.
Methods TATI was measured by radioimmunoassay from serum samples obtained within one week before surgery. A cutoff value of 22 μg/L was used. Multivariate analysis included pre-operative TATI level, age, histologic grade and histologic type. Mantel-Cox test was used for calculating statistical significance of differences in survival between groups.
Main outcome measures Cumulative five-year survival, pre-operative serum TATI level and residual tumour size.
Results Surgery was optimal (residual tumour size ≤ 2 cm) in 55 patients and suboptimal (residual tumour size > 2 cm) in 43. Pre-operative TATI level ≤ 22 μg/L predicted better prognosis both in patients with optimal and suboptimal surgery compared with patients with pre-operative TATI level > 22 μ/L. Patients with optimal surgery and a pre-operative TATI > 22 μg/L had a twofold relative risk of death compared with those with a pre-operative TATI ≤ 22 μg/L. The cumulative survival was less than three years for patients with suboptimal surgery and pre-operative TATI > 22 μg/L.
Conclusions Pre-operative serum TATI in combination with residual tumour size may be useful in stratifying patients with Stage III ovarian cancer into different categories in randomised treatment trials.  相似文献   
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Introduction. Currently the only treatment for celiac disease is a lifelong gluten-free diet. The diet is, however, often burdensome, and thus new treatment options are warranted. We isolated proteases from germinating wheat grain naturally meant for total digestion of wheat storage proteins and investigated whether these enzymes can diminish toxic effects of gluten in vitro and ex vivo.

Methods. Pepsin and trypsin digested (PT) gliadin was pretreated with proteases from germinating wheat, whereafter the degradation was analyzed by HPLC-MS (high-performance liquid chromatography and mass spectroscopy) and sodium dodecyl sulphate polyacrylamide gel electrophoresis. The toxicity of cleaved PT-gliadin products was assessed in Caco-2 epithelial cells, celiac patient-derived T cells, and in human small intestinal mucosal organ culture biopsies.

Results. Proteases from germinating wheat degraded gliadin into small peptide fragments, which, unlike unprocessed PT-gliadin, did not increase epithelial permeability, induce cytoskeletal rearrangement or changes in ZO-1 expression in Caco-2 cells. Pretreated gliadin did not stimulate T cell proliferation in vitro or enhance the production of autoantibodies to culture supernatants and the activation of CD25+ lymphocytes in the organ culture to the same extent as unprocessed PT-gliadin.

Discussion. Germinating wheat enzymes reduce the toxicity of wheat gliadin in vitro and ex vivo. Further studies are justified to develop an alternative therapy for celiac disease.  相似文献   
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