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RY Poon K Yamashita JP Adamczewski T Hunt J Shuttleworth 《Canadian Metallurgical Quarterly》1993,12(8):3123-3132
Activation of the cyclin-dependent protein kinases p34cdc2 and p33cdk2 requires binding with a cyclin partner and phosphorylation on the first threonine residue in the sequence THEVVTLWYRAPE. We present evidence that this threonine residue, number 160 in p33cdk2, can be specifically phosphorylated by a cdc2-related protein kinase from Xenopus oocytes called p40MO15. Binding to cyclin A and phosphorylation of this threonine are both required to activate fully the histone H1 kinase activity of p33cdk2. In cell extracts, a portion of p40MO15 is found in a high molecular weight complex that is considerably more active than a lower molecular weight form. Wild-type MO15 protein expressed in bacteria does not possess kinase activity, but acquires p33cdk2-T160 kinase activity after incubation with cell extract and ATP. We conclude that p40MO15 corresponds to CAK (cdc2/cdk2 activating kinase) and speculate that, like p33cdk2 and p34cdc2, p40MO15 requires activation by phosphorylation and association with a companion subunit. 相似文献
65.
Priapism is a urologic emergency. All patients should receive prompt urologic consultation. Management is based on prompt recognition, differentiation between low- and high-flow priapism, reversal of any potential precipitating factors, and the use of corporal aspiration/irrigation combined with intracavernosal alpha-agonist injection therapy. It cannot be over-emphasized that severely prolonged erections are associated with the development of irreversible problems with erectile function and, therefore, immediate and aggressive management is mandatory. 相似文献
66.
The authors report a case of pulmonary nocardiosis due to Nocardia nova occurring in a smoker who had a renal transplant. A pseudo-tumour was found on a standard X-ray and computerised tomography did not suggest the diagnosis. Needle aspiration under computerised tomographic control enabled a diagnosis to be made. 相似文献
67.
J Kattan S Culine MJ Terrier-Lacombe C Théodore JP Droz 《Canadian Metallurgical Quarterly》1993,4(10):871-875
BACKGROUND: Children with paratesticular rhabdomyosarcoma (RMS) have both a good prognosis and a high survival rate. The clinical behaviour and outcome of the disease in adults is not well described. PATIENTS AND METHODS: We reviewed retrospectively our experience with paratesticular RMS in patients older than 16 years during a 16-year period (1975-1991). RESULTS: Thirteen adult patients with paratesticular RMS are reported. Median age was 21 years (range 16 to 31). Presentation characteristics were scrotal mass in 11 cases, lumbar pain and weight loss in 5 cases, hypercalcemia in 3 cases and thrombocytopenia in 3 cases. There were 5 patients with stage IV, 2 with stage IIB and 6 with stage IA (IRS classification). The 5 stage IV patients are reported in detail, with initial bone marrow infiltration encountered in 4 of them. Objective response to chemotherapy was achieved in all 6 patients with measurable disease (2 CR + 4 PR). Two of 7 patients who received adjuvant chemotherapy relapsed at 7 and 11 months. After a median follow-up of 90 months, 8 patients (5 stage IV, 3 stage IA) died from disease progression. CONCLUSION: Metastatic disease with bone marrow involvement at presentation and aggressive behaviour seem to be more relevant in adult paratesticular RMS patients compared with children. 相似文献
68.
T Ojasoo E Bignon A Crastes de Paulet JC Doré J Gilbert JF Miquel M Pons JP Raynaud 《Canadian Metallurgical Quarterly》1993,44(3):239-250
A multivariate statistical method, correspondence factorial (CF) analysis, was used to examine the correlations among the protein binding and cell proliferation effects of a series of 36 di- and triphenylethylenes (DPEs and TPEs). The analysis was applied to a study which measured their competition for estradiol binding to cytosol estrogen receptor (ER), their influence on protein kinase C (PKC) activity under different conditions of enzyme activation, their ability to promote the growth of a breast cancer cell line and to inhibit growth at high concentrations (cytotoxicity). The CF analysis revealed several levels of correlation. First, it distinguished those molecules within the population that stimulated rather than inhibited PKC activity. Second, it made apparent a strong correlation between cytotoxicity and inhibition of Ca++ and phosphatidylserine-dependent PKC activity, which was most marked when the enzyme had been activated by diacylglycerol indicating that PKC inhibition under physiological conditions might contribute to the overall cytotoxicity of these compounds. Third, a lower level of correlation was established between competition for ER binding and cytotoxicity. Taken together, the results suggest that MCF7 cells might be most sensitive to a cytotoxic effect of TPEs (via PKC and other targets) when they at the same time decrease estrogen-stimulated proliferation via an ER-mediated antiestrogenic effect. 相似文献
69.
Prednisolone therapy of idiopathic feline lower urinary tract disease: a double-blind clinical study
CA Osborne JM Kruger JP Lulich GR Johnston DJ Polzin LK Ulrich J Sanna 《Canadian Metallurgical Quarterly》1996,26(3):563-569
A double-blind clinical study was performed to evaluate prednisolone as treatment for idiopathic feline lower urinary tract disease. No differences in response were observed in prednisolone- and placebo-treated cats. 相似文献
70.
R Legouis M Cohen-Salmon I del Castillo J Levilliers L Capy JP Mornow C Petit 《Canadian Metallurgical Quarterly》1993,17(2):516-518
The human KAL gene, responsible for the X-linked Kallmann syndrome, was isolated previously. Southern blot analysis using human cDNA probes detected cross-hybridization with DNA from several organisms, including chicken and quail. The entire coding sequences of chicken and quail KAL cDNAs were determined. A comparison of these cDNAs with the human KAL cDNA reveals an overall identity of 73 and 72%, respectively. This results in 76 and 75% identity at the protein level. The highest conservation was found in the WAP four-disulfide core motif and in two of the four fibronectin type III repeats reported in the human protein. These results further support the hypothesis that the KAL protein is an extracellular matrix component with anti-protease and adhesion functions. 相似文献