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乳腺管状小叶癌(Tubulolobular carcinoma,TLC)最初是被作为小叶癌的管状变型。作者总结了27例TLC的组织学、免疫表型和临床特征,并与纯小管癌和经典型小叶癌进行了比较。此组患者年龄43-79岁(中位年龄60岁)。1例双侧乳腺受累,5例病变为多灶性。肿瘤直径0.5-2.5cm,色灰褐,质硬。组织学观察:TLC的肿瘤细胞形成管状和条索状两种结构模式并相互混杂,且两者比例相当(统称为管状小叶模式)。  相似文献   
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Germline mutations of the CDKN2 gene in UK melanoma families   总被引:4,自引:1,他引:4  
Germline mutations in CDKN2 on chromosome 9p21, which codes for the cyclin D kinase inhibitor p16, and more rarely, mutations in the gene coding for CDK4, the protein to which p16 binds, underlie susceptibility in some melanoma families. We have sequenced all exons of CDKN2 and analysed the CDK4 gene for mutations in 27 UK families showing evidence of predisposition to melanoma. Five different germline mutations in CDKN2 were found in six families. Three of the mutations (Met53Ile, Arg24Pro and 23ins24) have been reported previously. We have identified two novel CDKN2 mutations (88delG and Ala118Thr) which are likely to be associated with the development of melanoma, because of their co-segregation with the disease and their likely functional effect on the CDKN2 protein. In binding assays the protein expressed from the previously described mutation, Met53Ile, did not bind to CDK4/CDK6, confirming its role as a causal mutation in the development of melanoma. Ala118Thr appeared to be functional in this assay. Arg24Pro appeared to bind to CDK6, but not to CDK4. No mutations were detected in exon 2 of CDK4, suggesting that causal mutations in this gene are uncommon. The penetrance of these mutant CDKN2 genes is not yet established, nor is the risk of non-melanoma cancer to gene carriers.   相似文献   
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BackgroundUse of the single-port da Vinci SP robotic platform for various urological procedures has been described by several groups. However, the comparative performance of the SP robot in relation to earlier models such as the da Vinci Xi is still unclear.ObjectiveTo compare intraoperative and short-term postoperative outcomes between the da Vinci Xi and SP robots for patients undergoing radical prostatectomy (RP) in a referral center.Design, setting, and participantsData were prospectively collected for patients undergoing RP from June 2019 to April 2020 in a single center. The da Vinci SP was used for 71 patients and the da Vinci Xi for 875 patients. After propensity score (PS) matching, two groups of 71 patients were selected for the comparative study.InterventionRP via a transperitoneal approach using the same technique steps and anatomy access with both robot consoles.Outcome measurements and statistical analysisA PS analysis was performed using the covariates age, body mass index, Charlson comorbidity index, Sexual Health Inventory for Men score, American Urological Association symptom score, prostate size, prostate-specific antigen levels, Gleason score, D’Amico risk group, and degree of nerve-sparing. Intraoperative performance and short-term functional (continence and potency) and oncological outcomes were compared between the groups.Results and limitationsMedian follow-up was 4.4 mo (interquartile range [IQR] 1.6–7.2) for the SP group and 3.2 mo (IQR 1.6–4.8) for the Xi group (p = 0.2). The median total operative time and median console time were both significantly higher in the SP group, with median differences of 14 min (95% confidence interval [CI] 9–19) and 5 min (95% CI 0–5), respectively. The proportion of patients with blood loss of >100 ml was significantly lower in the SP group (difference of 27%, 95% CI 12–42%). No intra- or postoperative complications were reported in either group. There were no significant differences in pain scores at 6, 12, and 18 h or in positive surgical margin rates between the groups. The SP group had a significantly higher percentage of extraprostatic extension than the Xi group (difference of 16%, 95% CI 4.6–27%). None of the patients experienced biochemical recurrence during follow-up. The difference in continence rates at 45 d between the SP and Xi groups was 11% (95% CI ?5.6% to 28%) and the difference in potency rates at 45 d was ?7.3% (95% CI ?21% to 6.2%). The short-term follow-up for comparison of functional and oncological outcomes is a limitation.ConclusionsDespite differences in trocar placement and technology between the two da Vinci consoles, the SP has satisfactory intraoperative performance compared to the Xi. SP surgery can be performed safely and effectively during the initial learning phase. However, longer-term follow-up is needed to provide further evidence on the impact of SP implementation on functional and oncological outcomes.Patient summaryWe compared intraoperative and short-term postoperative outcomes for patients who underwent radical prostatectomy using two different robots, the da Vinci Xi and the single-port da Vinci SP. We found that operative time was longer for the Single Port console. Studies with long-term follow-up are needed to compare the functional and oncological outcomes.  相似文献   
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Skin tumors induced in mice by initiation-promotion (2 microg DMBA-2 microg TPA) protocols were found to be under multigenic control. Eighty- one N2 mice from the cross (BALB/cAnPt x SENCARA/Pt)F1 x SENCARA/Pt that were either solidly resistant (no papillomas) or highly susceptible (> or = 7 papillomas/mouse) were subjected to a 'genome scan' using 89 microsatellite markers to check for associations with susceptible and resistant phenotypes. A locus on Chr 5 (Skts4) was found to control the susceptibility of SENCARA/Pt mice and the resistance of BALB/cAnPt mice to papilloma formation. In addition, higher than expected linkage scores were seen for the markers D9Mit271, D11Mit268 and D12Mit56. Further work is required to establish whether genes determining papilloma formation are located in these regions of the genome. In general, no evidence was seen for loss of heterozygosity in microsatellite markers on Chrs 5, 9 and 11 in 17 microdissected papillomas from (BALB/c x SENCARA)F1 hybrid mice.   相似文献   
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Multipotent mesenchymal stromal cells (MSCs) were first isolated from bone marrow and then from various adult tissues including placenta, cord blood, deciduous teeth, and amniotic fluid. MSCs are defined or characterized by their ability to adhere to plastic, to express specific surface antigens, and to differentiate into osteogenic, chondrogenic, adipogenic, and myogenic lineages. Although the molecular mechanisms that control MSC proliferation and differentiation are not well understood, the involvement of microRNAs has been reported. In the present study, we investigated the role of miR-125b during osteoblastic differentiation in humans. We found that miR-125b increased during osteoblastic differentiation, as well as Runx2 and ALPL genes. To study whether the gain or loss of miR-125b function influenced osteoblastic differentiation, we transfected MSCs with pre-miR-125b or anti-miR-125b and cultured the transfected cells in an osteoblastic differentiation medium. After transfection, no change was observed in osteoblastic differentiation, and Runx2, OPN, and ALPL gene expression were not changed. These results suggest that the gain or loss of miR-125b function does not influence levels of Runx2, OPN, and ALPL during osteoblastic differentiation.  相似文献   
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Interest in T-lymphocyte subsets has arisen because of their involvement in the autoimmune process. Contradictory results have been published in the literature about the number of peripheral blood lymphocyte subsets in autoimmune diseases. In order to investigate the number and distribution of peripheral blood lymphocyte subsets in autoimmune thyroid disease, the levels of total T-lymphocytes (CD3), T-helper (CD4) and T-suppressor/cytotoxic (CD8) lymphocytes were determined in 44 patients with Graves' disease (1), multinodular goiter (2) and Hashimoto's thyroiditis (3). All patients had high levels of antithyroglobulin and thyroid antiperoxidase (antimicrosomal) antibodies. The T subset levels were related to the functional thyroid status, measured as serum free thyroxine (FT4) and thyrotropin (TSH). Our data show the existence of a strong influence of functional status on CD3, CD4 and CD8 levels, as reflected in the significant correlations obtained with FT4 (negative) and TSH (positive). A significant decrease in all populations was observed in Graves' disease hyperthyroid patients. A decrease in the CD4/CD8 ratio in Hashimoto's thyroiditis hypothyroid patients was observed, in contrast to an increase in the ratio in autoimmune hyperthyroid patients. This points to the CD4/CD8 ratio as a differential characteristic between the two autoimmune (hypothyroid and hyperthyroid) entities, independent of free thyroxine levels. No significant correlation was found between antithyroid antibody levels and peripheral blood T-lymphocyte subsets or serum levels of FT4 and TSH.  相似文献   
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