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Molecular analyses of the mitotic checkpoint components hsMAD2, hBUB1 and hBUB3 in human cancer 总被引:10,自引:0,他引:10
Hernando E Orlow I Liberal V Nohales G Benezra R Cordon-Cardo C 《International journal of cancer. Journal international du cancer》2001,95(4):223-227
During the metaphase-anaphase transition, the spindle checkpoint prevents segregation of chromosomes if the spindle assembly is perturbed. Critical components of this checkpoint are the MAD and BUB families of proteins, which prevent the proteolysis of Pds1 and B cyclins, producing mitotic arrest. In the present study, we first intended to resolve the role of the hsMAD2 gene in human cancer by determining the potential presence of hsMAD2 mutations in 44 primary bladder tumors, 42 soft-tissue sarcomas and 10 hepatocellular carcinomas. The entire coding region of the hsMAD2 gene was analyzed using PCR-SSCP and sequencing. One of the bladder tumor samples showed a point mutation consisting of a transition, ATC-->GTC (Ile-->Val) in codon 190 of hsMAD2. However, no differences were found in the mitotic arrest between cells transfected with mutant and wild-type MAD2 cDNA. We also identified mobility shifts in hsMAD2 in both normal and tumor DNA in 3 bladder tumors, 3 soft-tissue sarcomas and 1 hepatocellular carcinoma, consistent with a polymorphism at codon 143, CCA-->CCG (Pro-->Pro). Another polymorphism was identified in a hepatocellular carcinoma case at codon 22, GAG-->GAA (Glu-->Glu). In addition, a subgroup of 67 primary tumors was analyzed by Southern blot hybridization. No deletion or visible re-arrangements were detected by comparing tumor and normal DNA band signals. Two other important components of the spindle mitotic checkpoint, hBUB1 and hBUB3, were also screened for mutations: hBUB1 in 43 bladder tumors and 9 bladder cell lines and hBUB3 only in the cell lines. Two polymorphisms were found in hBUB1 at positions 144, CAG-->CAA (Gln-->Gln) in 1 primary tumor and 1 bladder cell line, and 913 (ATC-->ATT, Ile-->Ile) in 1 primary tumor. We did not find sequence alterations in hBUB3. These results suggest that mutations of the hsMAD2, hBUB1 and hBUB3 genes are very rare in bladder tumors and that hsMAD2 alterations are also infrequent in soft-tissue sarcomas and hepatocellular carcinomas. 相似文献
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葛根素对高血压患者血浆内皮素和一氧化氮的影响 总被引:29,自引:0,他引:29
目的:检测正常人与高血压病(EH)患者血浆内皮素、一气体氮的变化及葛根素对其的干预效应。方法:EH对照组口服苯磺酸氨氯地平5mg/d,或合和盐酸苯那普利10mg/d,每日一次,15d为一疗程。EH伍用治疗组同时合用5%GNS250ml+葛根素注射液400mg静滴,两组治疗前后检测血浆ET、NO水平变化。结果:EH各组血浆ET较正常人组均显著增高(P〈0.01),血浆NO水平及NO/ET比值除轻度E 相似文献
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Magill HL; Clarke EA; Fitch SJ; Boulden TF; Ramirez R; Siegle RL; Somes GW 《Radiology》1986,161(3):625-630
A multicenter clinical study was conducted using iohexol, a second-generation nonionic contrast medium, for excretory urography performed in 130 children. Doses of iohexol (300 mg iodine/ml) ranged between 150 and 660 mgI/kg (0.5 and 2.2 ml/kg). Iohexol was tolerated well, and no significant adverse reactions occurred. Sixty-five iohexol urograms were evaluated to determine the minimum dose for adequate visualization of the kidneys and collecting systems. A dose greater than 300 mgI/kg (1.0 ml/kg) always resulted in a urogram of diagnostic quality, while visualization was insufficient for diagnosis in 10% of studies done with doses of 150-300 mgI/kg (0.5-1.0 ml/kg). Another 65 iohexol urograms were compared in a blinded manner with a similar number of studies performed using iothalamate meglumine at comparable iodine concentration and dose. Visualization of calyces and pelvoinfundibular structures achieved with iohexol was rated better with statistical significance, but there was no difference in visualization of the renal parenchyma or ureters. Use of iohexol in excretory urography may be advantageous in children who are at greatest risk for an adverse reaction to contrast media or in those most likely to benefit from use of a low osmolality contrast agent. 相似文献
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Scales for the measurement of attitudes toward blood donation 总被引:1,自引:0,他引:1
Attitudes toward blood donation are frequently assumed to vary along a single dimension from unfavorable to favorable. In contrast, theories of attitude structure specify three distinct attitude components: affect, cognition, and behavior. This article describes the development of three new scales for the measurement of affective, cognitive, and behavioral components of attitudes toward blood donation. The scales were developed using the method of equal-appearing intervals and were administered to both donors of blood and nondonors. Correlations among the scales were relatively small and supported the three-component distinction. Affect was more strongly correlated with the number of prior donations than was cognition, which suggested an important role for emotional factors in blood donation. Scores on all three scales showed the attitudes of blood donors to be more favorable than those of nondonors. 相似文献
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Pediatric patients with achondroplasia: CT evaluation of the craniocervical junction 总被引:2,自引:0,他引:2
Twenty-six patients (4 months to 6 years old) with achondroplasia complicated by sleep apnea and/or other neurologic manifestations underwent plain computed tomography (CT) of the craniocervical junction; six also underwent CT myelography. For objectification, multiplanar reconstruction was used to complement axial plane measurements by providing coronal and sagittal measurements; multiplanar reconstruction also improved perception of the longitudinal relationships between the brain stem and subarachnoid space. A narrow subarachnoid space was found in all 26 patients; marked cord compression was present in nine, six of whom underwent CT myelography. These six had marked focal obliteration of the subarachnoid space on both plain CT and CT myelography. Since the subarachnoid space immediately above and below the craniocervical junction is normally capacious, when marked constriction was present, no additional information could have been gained from CT myelography. Thus, plain CT was shown to be sufficient for surgical planning (suboccipital decompression) in nine patients with cord compression due to achondroplasia. 相似文献