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51.
RC Becker CP Cannon EG Bovill RP Tracy B Thompson GL Knatterud A Randall B Braunwald 《Canadian Metallurgical Quarterly》1996,78(2):142-147
The records of 60 patients with gallbladder carcinoma (GBC) operatively treated between 1966 and 1993 at Belen Hospital, Trujillo, Perú, were retrospectively reviewed. The ratio of men to women was 1:7.5 and the average of age was 61 years. The accuracy of ultrasonography and oral cholecystograms for the specific diagnosis was 21% and 0% respectively. The surgical procedures employed were simple cholecystectomy (n = 56), right hepatectomy (n = 2). Whipple operation (n = 1) and extended cholecystectomy (n = 1), and our resectability rate for GBC is currently 50%. Simple cholecystectomy was a potentially curative surgical procedure in patients with in situ cancer (stage O) and early GBC (stage 1). In hospital mortality was 11.6% and 5-year survival rate for the total series was 15%. Gallstones were present in 95% of patients and most tumors (58%) had grown by diffuse infiltration or were associated with empyema (38%). Tumor stage, depth of invasion, tumor grade histologic type were all predictive of patient outcome. This report reinforces the difficulty in diagnosis and the poor prognosis for patients with GBC. We hold the view that more radical approaches for invasive cancers will enhance the operative results. 相似文献
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CONTEXT: Although blacks receive lower doses of hemodialysis than whites, their survival when receiving dialysis treatment is better than that for whites. Previous studies of the relationship between the dose of dialysis and patient survival have not controlled for differences in patient characteristics. OBJECTIVE: To examine the association of mortality with the dose of hemodialysis for clusters of patients categorized by race and sex. DESIGN: Retrospective analysis of laboratory data and mortality outcomes from 1994, using a national database of hemodialysis patients. PATIENTS: A total of 18144 black and white patients receiving hemodialysis 3 times weekly who either lived the entire year receiving hemodialysis or died. MAIN OUTCOME MEASURES: The fractional reduction of urea in a single dialysis session as the measured hemodialysis dose (urea reduction ratio [URR]) after controlling for race, sex, age, and diabetes mellitus. Mortality was determined by strata of URRs and albumin and creatinine levels. RESULTS: Across all age categories, blacks had lower URRs than whites, and men had lower URRs than women. In an age-adjusted model for evaluating interactions among URRs, race, sex, and diabetes, the association of URR with mortality risk was weak among blacks, particularly black men. After adjustment for age and diabetes, death probability curves were most steep for white women with URR values less than 60%. The death probability curves were least steep for black men. There was no meaningful difference between death probability and albumin or creatinine concentration among the race by sex clusters. CONCLUSION: Using URR, the usual measure of hemodialysis dose, the assumption that the association between dialysis dose and survival is uniform across demographic groups appears incorrect. Comparisons of the quality of dialysis patient care should not rely on URR alone to predict patient survival. 相似文献
53.
G Cannella E Paoletti S Barocci F Massarino R Delfino G Ravera G Di Maio A Nocera P Patrone D Rolla 《Canadian Metallurgical Quarterly》1998,54(2):618-626
BACKGROUND: Prolonged antihypertensive therapy might be less effective in reversing the left ventricular hypertrophy (LVH) in uremics bearing the deleted (DD) allele of the angiotensin converting enzyme (ACE) gene than in patients with the inserted (II) allele or in those heterozygous (ID) for the gene. METHODS: Thirteen DD and 17 II + ID hemodialyzed uremics were followed-up with yearly echocardiography and 24-hour blood pressure (BP) monitoring over five years while on an antihypertensive therapy that included ACE inhibitors as first line drugs. RESULTS: In the II + ID group there were significant decreases of the left ventricular mass index (LVMi) and of both systolic and diastolic BPs. These changes were less pronounced in the DD group, but the difference was not statistically significant given the wide overlap between the two groups. Further analysis of the data revealed that the only factor associated to a decreased LVMi was the decrease of the systolic BP irrespective of the ACE gene genotype of each individual patient. CONCLUSIONS: The ACE-gene genotype does not necessarily predict the extent to which LVMi will be lowered by ACE-inhibitors therapy. The LVH of hypertensive uremics is amenable by long-term antihypertensive therapy provided that it results in significantly decreased systolic blood pressure. 相似文献
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C Bais B Santomasso O Coso L Arvanitakis EG Raaka JS Gutkind AS Asch E Cesarman MC Gershengorn EA Mesri MC Gerhengorn 《Canadian Metallurgical Quarterly》1998,391(6662):86-89
The Kaposi's sarcoma-associated herpesvirus (KSHV/HHV8) is a gamma-2 herpesvirus that is implicated in the pathogenesis of Kaposi's sarcoma and of primary effusion B-cell lymphomas (PELs). KSHV infects malignant and progenitor cells of Kaposi's sarcoma and PEL, it encodes putative oncogenes and genes that may cause Kaposi's sarcoma pathogenesis by stimulating angiogenesis. The G-protein-coupled receptor encoded by an open reading frame (ORF 74) of KSHV is expressed in Kaposi's sarcoma lesions and in PEL and stimulates signalling pathways linked to cell proliferation in a constitutive (agonist-independent) way. Here we show that signalling by this KSHV G-protein-coupled receptor leads to cell transformation and tumorigenicity, and induces a switch to an angiogenic phenotype mediated by vascular endothelial growth factor, an angiogenesis and Kaposi's-spindle-cell growth factor. We find that this receptor can activate two protein kinases, JNK/SAPK and p38MAPK, by triggering signalling cascades like those induced by inflammatory cytokines that are angiogenesis activators and mitogens for Kaposi's sarcoma cells and B cells. We conclude that the KSHV G-protein-coupled receptor is a viral oncogene that can exploit cell signalling pathways to induce transformation and angiogenesis in KSHV-mediated oncogenesis. 相似文献
56.
HD Connor RG Thurman G Chen JL Poyer EG Janzen RP Mason 《Canadian Metallurgical Quarterly》1998,24(9):1364-1368
It has been proposed that the C-phenyl-N-tert-butylnitrone/trichloromethyl radical adduct (PBN/.CCl3) is metabolized to either the C-phenyl-N-tert-butylnitrone/carbon dioxide anion radical adduct (PBN/.CO2-) or the glutathione (GSH) and CCl4-dependent PBN radical adduct (PBN/[GSH-.CCl3]). Inclusion of PBN/.CCl3 in microsomal incubations containing GSH, nicotinamide adenine dinucleotide phosphate (NADPH), or GSH plus NADPH produced no electron spin resonance (ESR) spectral data indicative of the formation of either the PBN/[GSH-.CCl3] or PBN/.CO2- radical adducts. Microsomes alone or with GSH had no effect on the PBN/.CCl3 radical adduct. Addition of NADPH to a microsomal system containing PBN/.CCl3 presumably reduced the radical adduct to its ESR-silent hydroxylamine because no ESR signal was observed. The Folch extract of this system produced an ESR spectrum that was a composite of two radicals, one of which had hyperfine coupling constants identical to those of PBN/.CCl3. We conclude that PBN/.CCl3 is not metabolized into either PBN/[GSH-.CCl3] or PBN/.CO2- in microsomal systems. 相似文献
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