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We describe a female stillbirth with duplication of 3q21-->qter and deletion of 11q23-->qter resulting from an unbalanced segregation of a maternal t(3;11) reciprocal translocation. The proband had some of the clinical features consistent with those seen in patients with dup(3q) syndrome or distal del(11q) syndrome. Prenatal sonographic examination showed short limbs, intrauterine growth retardation, and an omphalocele containing the liver. 相似文献
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Mutation in transcription factor POU4F3 associated with inherited progressive hearing loss in humans
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H Schwarzenberg S Müller-Hülsbeck CC Glüer F Wesner M Heller 《Canadian Metallurgical Quarterly》1998,170(5):1181-1185
OBJECTIVE: Our objective was to compare intravascular sonography with digital subtraction angiography (DSA) in the assessment of luminal dimension and morphologic features of endovascular stents and stent grafts. MATERIALS AND METHODS: Thirty-seven pelvic and 24 femoral stents (12 Wall-stents; 27 covered and 22 uncovered nitinol stents) in 50 patients were evaluated 15 +/- 10 months after implantation by DSA and intravascular sonography. The degree of maximum instent restenosis as revealed by DSA and intravascular sonography was compared for each location. Morphologic features of the stents and stenoses were also assessed. RESULTS: Intravascular sonography and DSA correlated well (R2 = .96) in determining in-stent restenosis. In-stent restenosis was underestimated by 13% +/- 6% by DSA compared with intravascular sonography. Differences in determining in-stent restenosis with intravascular sonography and DSA were not associated with severity of stenosis or type of stent. Intravascular sonography revealed incomplete expansion of stents in 21 cases, whereas DSA revealed incomplete expansion of stents in seven cases. The intra- and interobserver variabilities in our study were 4% and 5%, respectively. CONCLUSION: In-stent restenoses are underestimated with DSA. Intravascular sonography is superior to DSA for detection of incomplete stent expansion. 相似文献
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CC Helbing CL Wellington M Gogela-Spehar T Cheng GG Pinchbeck RN Johnston 《Canadian Metallurgical Quarterly》1998,17(12):1491-1501
When exposed to diverse growth conditions in vitro, cells can respond by entering states of proliferation, quiescence, differentiation or apoptosis. While the choices among these states can be influenced by proto-oncogene expression, how these disparate outcomes are achieved remains poorly understood. To address these issues, we have generated rodent fibroblast cell lines that harbor a human c-myc gene under the control of a tetracycline-regulated promoter. When Myc-induced cells are deprived of serum growth factors, they rapidly become apoptotic with the onset of apoptosis preceded by a large, transient increase in cdk2 kinase activity that is associated with the induction of cdc25A phosphatase and the later accumulation of p27Kip1 kinase inhibitor. Surprisingly, serum starvation in the absence of myc overexpression, (which leads to quiescence instead of apoptosis) also causes a marked transient elevation in cdk2 kinase activity, an induction of cdc25A and a delayed increase in p27Kip1. Transient elevations in cdk2 kinase activity and cdc25A abundance are required for cell cycle progression, but it is evident that these changes also precede entry to either apoptosis or quiescence in serum-starved cells. These findings suggest that the pathways to both quiescence and apoptosis share regulatory machinery with cell cycle control mechanisms. In addition, the abundance of Myc protein can be critical in the choices among these cellular states. 相似文献
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CC Szeto CC Chow KY Li TC Ko VT Yeung CS Cockram 《Canadian Metallurgical Quarterly》1996,35(3):289-291
We report a case of oesophageal disease as the first manifestation in a patient with CREST syndrome. A 46-year-old man with achalasia-like syndrome developed CREST syndrome 4 years later. A pneumatic dilatation of the cardia was performed. After pneumatic dilatation the dysphagia and regurgitation disappeared but the patient developed reflux oesophagitis. Four years after diagnosis of oesophageal disease he presented with a clinical picture of CREST syndrome. An acute ileus and constipation developed later. After receiving medical therapy with omeprazole and cisapride the patient is free of oesophageal symptoms and bowel movements are normal. Oesophageal disease is common in patients with limited and diffuse scleroderma, but to our knowledge achalasia-like syndrome has not been previously described as the first manifestation of the systemic disease. 相似文献
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A Zlotta A Drowart JP van Vooren J Simon CC Schulman K Huygen 《Canadian Metallurgical Quarterly》1994,62(3):63-68
Prophylactic treatment with Bacillus Calmette-Guerin (BCG) is an established and effective therapy of bladder cancer. The antitumor effect of BCG seems to be largely related to cellular immunological mechanisms, although its precise mode of action is unknown. Antitumor response of BCG seems to be initiated by the attachment of BCG to bladder wall via Fibronectin (FN). The cellular immune response against Tuberculin PPD and the major secreted BCG antigen (Fibronectin-binding AG 85 complex) has been tested in a control group of 20 untreated bladder tumor patients and before and after 6 weekly intravesical BCG instillations in a group of 20 superficial bladder tumor patients. A major increase in the lymphoproliferative response against PPD and AG 85 was observed in respectively 66% and 57% of the treated patients. In contrast, no detectable antibody response (IgA, IgM, IgG) was observed against AG 85 complex after BCG treatment. On the other hand, antibodies against Tuberculin increased in 13 of 20 patients. This study seems to demonstrate a specific cellular immune activation against AG 85 Fibronectin-binding complex during BCG treatment of superficial bladder tumors. Humoral response against the AG 85 is not activated after BCG treatment. Further studies are needed to elucidate the role of AG 85 in the cellular intravesical penetration of BCG. Presence or absence of cellular response against this antigen could be of clinical value. 相似文献