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Purpose BRAF V600E mutation represents the most common oncogenic event in sporadic papillary thyroid cancer (PTC). There are, however, significant discrepancies regarding the overall frequency, its prevalence in PTC‐variants, and its relationship with clinico‐pathological parameters of poor outcome. Moreover, the impact of BRAFV600E mutants on tumour‐related patient's death has not been evaluated. Design We analysed, by PCR‐SSCP and/or PCR‐direct sequencing, exons 8, 10, 11 and 15 of BRAF in 113 tumour samples from 49 PTC‐patients. Matched lymph node metastases and/or distant metastases (DMs) were screened in 35 patients. Focal changes in the growth pattern or microscopic grade within the primary tumour (Pt) or the metastases were separately genotyped. Mutations at H‐, K‐, N‐ras and PIK3CA exons 9 and 20 were also investigated. For comparison with PTC cases, the BRAF and Ras mutational status was evaluated in 89 specimens obtained from 24 poorly differentiated thyroid carcinomas (PDCs) and 36 anaplastic thyroid carcinomas (ATCs). Results BRAF V600E was found in 13/16 classical PTCs (CL‐PTCs), 6/17 follicular variant PTCs (FV‐PTCs) and 8/16 mixed (papillary/follicular) PTCs (Mx‐PTCs), being significantly associated with CL‐PTCs (P = 0·015). BRAFV600E segregated with metastatic PTC‐cells in 43% of the patients, but only one DM disclosed the mutation. PTC‐tumours featuring concurrent less‐differentiated foci were BRAF wild‐type in both components. Noteworthy, the frequency of BRAF mutations among PDCs and ATCs resulted considerably lower (16·6% and 25%, respectively) than in PTCs (55%). The prevalence of Ras mutations among PDCs and ATCs (46% and 36%, respectively) was, however, much higher than in PTCs (14%). Five (71%) of the patients who died of PTC displayed somatic mutations. Four of them had other gene alteration associated with BRAFV600E and the only one that did not, BRAFV600E was restricted to the Pt. The occurrence of BRAFV600E associated with other genetic events was an independent predictor of DMs during follow‐up, recurrence and tumour‐related death. Remarkably, two PDCs (8·3%) and five ATCs (14%) revealed concurrent BRAF and Ras mutations. Conclusion BRAF V600E‘alone’ does not represent a marker for poor outcome, however, when associated with alterations in other genes identifies a subset of PTCs with increased risk of recurrence and decreased survival.  相似文献   
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A new cam is reported of müllerian adenosarcoma, presenting as a 'benign cervical polyp' protruding through the vulva of a 44 yearold woman admitted with abnormal vaginal bleeding. This report emphasizes the importance of a careful examination of the stroma and special features of the entrapped glands in order to contribute to an earlier and proper diagnosis. The literature is reviewed and the probable histogenesis of this tumor and differential diagnosis with embryonal rhabdomysarcoma (sarcoma botryoides), adenofibroma, malignant mesodermal tumor and carcino-sarcoma is discussed.  相似文献   
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Thyroid oncocytic (Hürthle cell) neoplasms represent a distinct subset of follicular thyroid tumors characterized by abnormal accumulation of mitochondria, whose chromosomal abnormalities have never been systematically analyzed. We have used comparative genomic hybridization to investigate chromosomal DNA alterations in 11 thyroid oncocytic tumors (7 adenomas and 4 carcinomas). Unbalanced chromosomal DNA profiles were detected in 6 of 7 adenomas and 3 of 4 carcinomas, numerical chromosomal aberrations being the dominant feature. Comparative genomic hybridization findings are compatible with two separate groups of tumors with karyotypic abnormalities, one characterized by multiple chromosomal gains with polysomy of chromosomes 5 and 7, the other by loss of chromosome 2. Pathologic and clinical features were similar in the two groups with no difference observed between adenomas and carcinomas. Activating H-, K-, or N-Ras mutations are commonly detected in follicular adenomas and carcinomas of the thyroid gland. However, Ras mutational analysis demonstrated that only one of the tumors in this series, an oncocytic carcinoma with a balanced karyotype, had activating Ras mutations (at codon 13 of K-Ras). The lack of Ras mutations in the 9 oncocytic neoplasms exhibiting chromosomal aneuploidy indicates that numerical chromosomal abnormalities are independent of activating Ras mutations in oncocytic tumors.  相似文献   
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Poorly differentiated carcinoma of the thyroid gland (PDC) represents an heterogeneous group of epithelial neoplasms with morphologic features and clinical characteristics intermediate between well differentiated and anaplastic (undifferentiated) carcinomas. Unlike well differentiated tumors, PDCs are associated with significant morbidity and mortality. The general prevalence of RET/PTC rearrangement in thyroid PDC and its impact on patient outcome are unknown. To address these issues and to identify prognostically relevant clinicopathologic parameters, we have investigated a series of 62 PDCs. RET/PTC rearrangement, analyzed by RT-PCR and immunohistochemistry using antibodies specific for the tyrosine kinase and juxtamembrane portions of the RET protein, was identified in 8/62 (12.9%) PDCs. RET/PTC was more common in cases with histologic evidence indicating coexistence with or possible evolution from a well differentiated papillary carcinoma (5 of 25 tumors, 20%) but did not correlate with other clinicopathologic parameters. The relatively low prevalence of RET activation in PDCs argues against a major role for RET/PTC in the progression from well to poorly differentiated thyroid tumor phenotypes. Survival analysis demonstrates that poor survival in PDC is associated with old age, male sex, invasion of extrathyroidal soft tissues, coexistence in the same tumor of oncocytic features with insular growth pattern, and distant metastases but not RET activation.  相似文献   
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Male circumcision has been shown to reduce the risk of acquiring and transmitting a number of venereal infections. However, little is known about the association between male circumcision and the risk of Chlamydia trachomatis infection in the female partner. The authors pooled data on 305 adult couples enrolled as controls in one of five case-control studies of invasive cervical cancer conducted in Thailand, the Philippines, Brazil, Colombia, and Spain between 1985 and 1997. Women provided blood samples for C. trachomatis and Chlamydia pneumoniae antibody detection; a type-specific microfluorescence assay was used. Multivariate odds ratios were computed for the association between male circumcision status and chlamydial seropositivity in women. Compared with women with uncircumcised partners, those with circumcised partners had a 5.6-fold reduced risk of testing seropositive for C. trachomatis (82% reduction; odds ratio = 0.18, 95% confidence interval: 0.05, 0.58). The inverse association was also observed after restricting the analysis to monogamous women and their only male partners (odds ratio = 0.21, 95% confidence interval: 0.06, 0.72). In contrast, seropositivity to C. pneumoniae, a non-sexually-transmitted infection, was not significantly related to circumcision status of the male partner. These findings suggest that male circumcision could reduce the risk of C. trachomatis infection in female sexual partners.  相似文献   
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