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91.
Sorex araneus and Sorex granarius are sibling species within the Sorex araneus group with karyotypes composed of almost identical chromosome arms. S. granarius has a largely acrocentric karyotype, while, in S. araneus, various of these acrocentrics have combined together by Robertsonian (Rb) fusions to form metacentrics, with the numbers and types of metacentrics differing between chromosomal races. Our studies on telomeric sequences in S. araneus and S. granarius revealed differences between chromosomes and between species. In S. araneus (the Novosibirsk race), hybridization signals were present on the telomeres of all the chromosomes after FISH with a PCR-generated telomeric probe. In addition, hybridization signals were observed at high frequencies in the pericentric regions of some but not all metacentrics formed by Rb fusion. There were fewer signals on those metacentrics formed earlier in the evolution of S. araneus. This suggests that S. araneus chromosomes retain at least some telomeric repeats during Rb fusion, but that these repeats are lost or modified over time. These results are critical for the interpretation of the well-studied hybrid zones between chromosomal races of S. araneus, given that Rb fission has been postulated in such hybrid zones and that the likelihood of Rb fission will relate to presence/absence of telomeric sequences at the centromeres of metacentrics. In S. granarius, there were strong signals at the proximal (centromeric) telomeres of the acrocentrics after FISH with a DNA telomeric probe. FISH with a PNA telomeric probe on S. granarius acrocentrics showed that the proximal telomeres were 213 kb on average, while the length of the distal telomeres was 3.8 kb on average. Two-colour FISH, using a telomeric DNA probe and a microdissected probe generated from the pericentric regions of the S. granarius chromosomes a and b, revealed regions on distinct chromatin fibres where telomeric and microdissected probes were colocalized or localized sequentially. The proximal telomeres of S. granarius are highly unusual both in their large size and their heterogeneous structure relative to the telomeres of other mammals.  相似文献   
92.
Objective Discussion of diagnosis, treatment and prognosis of non-palpable TO breast cancer. Methods Between 1978 and 1997, 9,980 female patients with operable breast cancer were treated surgically, of which 276 were determined to have TO breast cancer. Most TO breast cancers could be detected promptly with careful examination of presenting symptoms, such as nipple discharge, local thickening of the breast, nipple erosion, nipple retraction and postmenopausal mastalgia, while 12 cases were detected by routine mammography of the contralateral breast. Results All patients were treated surgically and their tissue subjected to histopathological examination. Most cases (73.0%) were noninvasive or early invasive carcinoma. Axillary lymph nodes metastases were found in 7.69% of 234 mastectomy cases. Conclusion The survival rate was significantly increased if the tumor was in an early stage. The 5-, 10-, 15-years survival rates were 98.1%, 94.6% and 90.3%, respectively.  相似文献   
93.
目的总结23例乳腺派杰氏(Paget’s)病患者的诊断及治疗。方法收集我院自1984~2004年23例经病理确诊的乳腺Paget’s病例,通过对病人的临床资料及治疗方法的分析,总结该病的诊治经验。结果乳腺Paget’s病以慢性乳头皮肤改变为主要特点,钼靶X线多显示导管区恶性改变。细胞学检查见到Paget’s细胞。术后7例失访,余16例随访时间最长13年,最短6月,其中3例出现术后远处转移。结论早期诊断及手术为主的综合治疗预后较佳。  相似文献   
94.
A prospective study of seeding of the skin after core biopsy of the breast   总被引:2,自引:0,他引:2  
BACKGROUND: The number of core biopsies done for breast abnormalities is increasing. The risk of skin seeding resulting from core biopsy is unknown. METHODS: Consecutive patients diagnosed with breast cancer were studied. The skin and subcutaneous fat surrounding the site of core needle penetration were excised and studied by routine histologic staining. Findings were correlated with other clinical variables. RESULTS: Eighty-nine consecutive patients were studied. Thirty-one had stereotactic core biopsies, 23 had vacuum-assisted biopsy, 8 had multiple-puncture biopsy, and 58 had ultrasound-guided core biopsy. Two patients who were biopsied using multiple-puncture biopsy were found to have nests of cancer cells in the dermis. One of these patients had recurrence in the skin biopsy site at 34 months. CONCLUSION: Skin seeding may be important in light of increasing use of image-directed biopsy, and particularly for cases in which the biopsy puncture site is outside the index quadrant and in which no radiation is anticipated.  相似文献   
95.
原发性乳腺鳞状细胞癌临床病理分析   总被引:1,自引:0,他引:1  
回顾性分析11例原发性乳腺鳞状细胞癌(primary squamous cell careinoma of the breast,PSCCB)患者的临床病理资料.11例均行手术治疗,术后病理检查4例发生腋窝淋巴结转移,生存超过5年的7例,3例死于肿瘤复发和转移.回顾性研究的结果提示,PSCCB患者的临床表现与普通类型的乳腺癌比较无特异性,确诊需依据病理诊断,由于其发病率低,规范的治疗和预后评价有待进一步研究.  相似文献   
96.
There have been several well-established multi-centered clinical trails about breast conserving therapy (BCT) published their results and showed that for appropriately selected and staged patients with early invasive carcinoma of the breast, breast conservation therapy has been shown to result in survival rates and local recurrence rates comparable to those achieved with mastectomy while preserving the breast[1,2]. In 1995, our hospital began breast conserving therapy of early stage breast can…  相似文献   
97.
OBJECTIVE To evaluate the incidence of residual thyroid cancer and cervical lymph node metastasis following a previous local resection for thyroid cancer, and to discuss methods of a reoperation.METHODS From 1994~2005, 118 patients with thyroid cancer who had previously been treated with a nodule-resection or subtotal Iobectomy in other hospitals underwent a surgical re-operation.RESULTS The incidence of residual cancer at the primary site was 38.1%. The lymph node metastasis rate at the central area was 39.8%.The rate of lymph node metastasis in patients with enlarged lymph nodes in the ipsilateral internal jugular chain was 37.5%. The rate of laryngeal recurrent nerve injury was 15.2% in other hospitals while that of the second operation in our hospital was 1.6%.CONCLUSION Nodule-resection or subtotal Iobectomy alone is not indicated for patients with thyroid cancer because of the high rate of local residual cancer. It is important to be familiar with the anatomy of the laryngeal recurrent nerve for thyroid surgery. Exploration to the central area is necessary for differentiated thyroid cancer.  相似文献   
98.
99.
【摘要】 目的 探讨基质金属蛋白酶抑制剂(RECK)、基质金属蛋白酶 9(MMP 9)在三阴性乳腺癌(TNBC)组织、癌旁组织中的表达及与TNBC临床病理的关系。方法 选择绵阳市中心医院乳腺外科2011年5月~2013年7月经病理证实为TNBC的72例石蜡标本及同 患者癌旁组织,利用免疫组化组织芯片技术检测其RECK、MMP 9蛋白的表达。结果 RECK在TNBC组织及癌旁组织中阳性表达率分别为4306%、8056%(P=0000)。TNBC中RECK的表达与临床分期(P=0009)、组织学分级(P=0010)、腋窝淋巴结转移情况(P=0000)相关。MMP 9在TNBC组织及癌旁组织中阳性表达率分别为625%、1528%(P=0000)。TNBC中MMP 9的表达与肿瘤大小(P=0017)、临床分期(P=0001)、组织学分级(P=0001)、腋窝淋巴结转移状况(P=0001)、Ki 67表达情况(P=0034)相关。TNBC中RECK与MMP 9表达呈负相关(r= 0195,P<005)。结论 RECK的表达缺失与MMP 9过度表达与TNBC浸润、转移有关,有望成为TNBC的预后指标,并且有可能成为TNBC治疗的靶点。  相似文献   
100.
NIMA Related Kinase 6 (Nek6) is a protein kinase involved in various cellular processes, including cell cycle regulation, apopotosis, senescence, telomere maintainance and chemoresistance. In the present study, we investigated the role of Nek6 in breast tumorigenesis and the prognostic merit of Nek6 expression in breast cancer. Immunohistochemistry and Western blot analyses was conducted to determine the expression profile of Nek6 in 133 breast cancer specimens. Nek6 was overexpressed in a majority of breast cancer specimens, compared with the adjacent non-tumorous tissues. Furthermore, we revealed that high expression of Nek6 was associated with histologic grade, tumor size and TNM stage in breast cancer. Liner regression analysis showed a significant association between the levels of Nek6 and Ki-67. Cox regression analysis indicated that Nek6 expression was an independent prognostic predictor for breast cancer. Moreover, intracellular level of Nek6 was remarkably increased following the release from serum starvation in MCF-7 cells. EdU incorporation assay indicated that depletion of Nek6 remarkably impaired the proliferation of MCF-7 cells. Finally, spheroid formation assay revealed that interference of Nek6 led to diminished oncospheroid-forming capacity of breast cancer cells. In conclusion, our results imply that Nek6 plays a facilitating role in breast cancer cell proliferation and may serve as a promising therapeutic target for breast cancer.  相似文献   
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