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排序方式: 共有2439条查询结果,搜索用时 234 毫秒
31.
c-erbB-2 related aggressiveness in breast cancer is hypoxia inducible factor-1alpha dependent. 总被引:4,自引:0,他引:4
Alexandra Giatromanolaki Michael I Koukourakis Costantinos Simopoulos Alexandros Polychronidis Kevin C Gatter Adrian L Harris Efthimios Sivridis 《Clinical cancer research》2004,10(23):7972-7977
c-erbB-2-positive breast carcinomas are highly aggressive tumors. In vitro data on breast cell lines showed that c-erbB-2 enhanced translational efficiency of hypoxia inducible factor-1alpha (HIF1alpha) production (Laughner et al., Mol Cell Biol 2001;21:3995-4005). We investigated the clinical correlate of this observation to assess whether c-erbB-2 expression was related to HIF1alpha expression, angiogenesis, and prognosis. A series of 180 breast carcinomas of known c-erbB-2 status (90 c-erbB-2-positive and 90 c-erbB-2-negative carcinomas) were stained immunohistochemically for HIF1alpha and CD31 endothelial cell antigen. c-erbB-2 positivity was clearly related to HIF1alpha protein expression and high angiogenesis. However, prognosis was decreased only in cases with simultaneous c-erbB-2 and HIF1alpha expression. If activation of c-erbB-2 in humans results in overexpression of HIF1alpha independently of conditions of hypoxia, as occur in experimental studies, this interaction may represent a main pathway conferring clinical aggressiveness to c-erbB-2-positive breast tumors. 相似文献
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OBJECTIVES: To re-examine the potential influence of varicocelectomy on testicular volume using scrotal ultrasonography, because it has been reported that total testicular volume (assessed by physical examination) increases after adult varicocele ligation. METHODS: A retrospective review of the testicular volume and semen parameters of 61 men who underwent microsurgical varicocelectomy between 1996 and 1998 was performed. Ultrasound-derived testicular volumes and total motile sperm counts were compared before varicocelectomy and at a mean of 7.2 months postoperatively. RESULTS: Bilateral varicocelectomy was performed in 22 men; 39 men underwent a left-sided procedure only. Overall, no significant change was found in the mean total testicular volume after varicocelectomy compared with preoperatively (24.0 versus 23.9 mL, respectively; P = 0.74). Similarly, the testicular volumes did not change significantly after left or bilateral varicocelectomy (P >0.05). Overall, the mean total motile sperm count increased significantly after varicocelectomy (17. 9 to 25.4, P = 0.05). CONCLUSIONS: This was the first study to examine the effect of adult varicocelectomy on testicular volume using ultrasound-derived measurements of volume. Unlike previous findings, our data suggest that although adult varicocelectomy improves semen quality in most infertile men, it does not result in a significant increase in testicular volume. 相似文献
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Alexandros Papanikolaou Qian-Shu Wang Don A. Delker Daniel W. Rosenberg 《Cancer letters》1998,130(1-2):29-34
Azoxymethane (AOM) is an organotropic colon carcinogen that is commonly used to induce colon tumors in rodents. Unlike its parent compound, 1,2-dimethylhydrazine (DMH), a tumor susceptibility phenotype in inbred mice with respect to AOM has not been established. Thus, this study was undertaken to determine whether genetic susceptibility extends to this carcinogen. SWR/J, A/J (both susceptible to DMH carcinogenesis) and AKR/J (resistant) mice were treated with 10 mg/kg AOM i.p. once a week for 8 weeks. Twenty-five weeks after the initial injection, tumor yield was determined. With a single exception, only SWR/J and A/J mice developed tumors, with a distribution that was limited to the distal colon (16.3±1.1 and 36.4±2.4, respectively). The formation of aberrant crypt foci (ACF), putative preneoplastic lesions, was also assessed in whole-mount colons using Methylene Blue staining. Consistent with tumor multiplicity, the total number of ACF was highest in A/J mice, followed by SWR/J mice. In addition, A/J mice had a significantly greater number of large ACF (five or more crypts per foci) than the other strains. Despite the absence of colon tumors, however, AKR/J mice did develop a significant number of ACF. This finding suggests that ACF in resistant mice are persistent but do not progress to tumors. 相似文献
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Konstantinos C. Theodoropoulos MD MSc Alexandros Papachristidis MD Michael Papitsas MD Jonathan Byrne MBChB PhD FRCP Mark J. Monaghan PhD FRCP FACC FESC 《Echocardiography (Mount Kisco, N.Y.)》2018,35(1):132-134
We present a case of a 68‐year‐old man with calciphylaxis, who was found to have a floating thrombus in the descending aorta on a transesophageal echocardiogram. The use of 3D echocardiography demonstrated nicely the free motion of the thrombus, emerging from an atherosclerotic plaque in the descending aorta. Anticoagulation was started for thromboembolism prevention. 相似文献
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