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排序方式: 共有2211条查询结果,搜索用时 0 毫秒
991.
992.
HC Chen MH Cheng AG Schneeberger TJ Cheng FC Wei YB Tang 《Canadian Metallurgical Quarterly》1998,45(3):570-574
Damage of large arteries is a major contributory factor to the high pulse pressure observed in patients with end-stage renal disease. Whether incremental modulus of elasticity (Einc), a classic marker of arterial stiffness, can predict cardiovascular mortality has never been investigated. A cohort of 79 patients with end-stage renal disease undergoing hemodialysis was studied between September 1995 and January 1998. Mean age at entry was 58+/-15 years. The duration of follow-up was 25+/-7 months, during which 10 cardiovascular and 8 noncardiovascular fatal events occurred. At entry, carotid Einc was calculated from measurements of diameter, thickness (echo-tracking technique), and pulse pressure (tonometry). Based on Cox analyses, 2 dominant factors emerged as predictors of all-cause and cardiovascular mortality: increased Einc and decreased diastolic blood pressure. Lipid abnormalities and the presence of previous cardiovascular events interfered to a smaller extent. After adjustment for confounding variables, the odds ratio for Einc >/=1 kPa-3 was 9.2 (95% confidence interval, 2.4 to 35.0) for all-cause mortality. These results provide the first direct evidence that in patients with end-stage renal disease undergoing hemodialysis, arterial alterations, as determined from carotid Einc, are strong independent predictors of all-cause and cardiovascular mortality. 相似文献
993.
BS Preiss GB Kerndrup KG Schmidt AG S?rensen NA Clausen OV Gadeberg T Mourits-Andersen NT Pedersen 《Canadian Metallurgical Quarterly》2003,123(2):219-234
During a 10-year period (1992-2001) in the region of Southern Denmark, 337 patients aged 15 years or older (range 16-93 years, median 67 years) were diagnosed with acute myeloid leukaemia (AML). Cytogenetic analysis was carried out in 90%, of whom 53% had clonal chromosome aberrations. Some 24% and 31% had only numerical or structural abnormalities respectively. The remaining patients showed both types of abnormalities. Ploidy levels in decreasing order were: pseudodiploidy, 41%; hyperdiploidy, 32%; and hypodiploidy, 27%. Pseudodiploidy characterizes type M3 (70%) and hypodiploidy M6 (56%). Recurrent cytogenetic abnormalities--t(8;21), t(15;17) and inv(16)--were found in 3.3%, 3.3% and 2.0% of all patients respectively. Prognostically intermediate and adverse aberrations were found in 39% and 44%, respectively, of those with an abnormal karyotype. Rare recurrent aberrations were found in two patients in this material. A previously described non-recurrent abnormality was found to be recurrent in one patient [der(20)t(11;20)(q13.2;p13)]. New, previously undescribed abnormalities were found in 41 patients. Statistically significant correlations were found between t(15;17) and young age (P < 0.001), inv(16) and young age (P < 0.006), -17 and M6 (P = 0.007), and M6 and complex karyotype with five or more unrelated aberrations (P = 0.004). We conclude that this truly population-based cytogenetic study of adult AML showed distributions of chromosome abnormalities that differ from those described so far. 相似文献
994.
995.
MA Jewett C Bombardier AG Logan KE Psihramis T Wesley-James JE Mahoney JJ Luymes D Iba?ez MR Ryan RJ Honey 《Canadian Metallurgical Quarterly》1998,160(4):1241-1243
PURPOSE: To answer the question of whether extracorporeal shock wave lithotripsy (ESWL*) induces hypertension, a prospective, randomized controlled trial of normotensive patients with asymptomatic renal calculi was designed. MATERIALS AND METHODS: Patients were randomized to receive immediate ESWL versus observation, reserving ESWL for the onset of symptoms. The rates of new onset hypertension were evaluated for both groups. RESULTS: There was no observed difference in the incidence of hypertension between the treatment and observation groups. CONCLUSIONS: The risk of hypertension in patients undergoing ESWL therapy is similar to that of a control cohort of initially observed asymptomatic patients. 相似文献
996.
D Hrouda BE Souberbielle J Kayaga CM Corbishley RS Kirby AG Dalgleish 《Canadian Metallurgical Quarterly》1998,82(6):870-876
OBJECTIVE: To evaluate the potential of heat-killed Mycobacterium vaccae (SRL172) as a nonspecific immunostimulant and as an adjuvant to whole tumour cell vaccination in the rat model of prostate cancer. MATERIALS AND METHODS: SRL172 was used as a vaccine in the prevention and treatment of subcutaneous tumours in rats. Prevention experiments were conducted using subcutaneous MAT-LyLu tumours in Copenhagen rats, comparing vaccination with SRL172 alone, SRL172 plus autologous cells, and bacille Calmette-Guèrin (BCG) plus autologous cells before tumour implantation. Treatment experiments were conducted using subcutaneous MAT-LyLu tumours in the Copenhagen rat and subcutaneous PAIII tumours in the Lobund-Wistar rat. Tumours were induced by subcutaneous injection with tumour cells. Animals were then vaccinated with autologous cells, autologous cells plus SRL172, or SRL172 alone. RESULTS: SRL172 was effective as an adjuvant to autologous whole tumour cell vaccination in the prevention of MAT-LyLu tumours and the survival benefit was equivalent to that provided when the adjuvant was live-attenuated BCG. SRL172 alone did not reduce tumour take or tumour growth in this model and neither strategy was effective in delaying the growth of established MAT-LyLu tumours. In the Lobund-Wistar rat vaccination with autologous whole tumour cells and SRL172 significantly delayed the growth of established tumours. CONCLUSION: Mycobacterium vaccae deserves further evaluation as an adjuvant to whole tumour cell vaccination in a phase I clinical trial in patients with prostate cancer. 相似文献
997.
MO MCarron KW Muir CJ Weir AG Dyker I Bone JA Nicoll KR Lees 《Canadian Metallurgical Quarterly》1998,29(9):1882-1887
BACKGROUND AND PURPOSE: Polymorphism of the apolipoprotein E gene (APOE) may influence outcome after traumatic brain injury and intracerebral hemorrhage, with the epsilon4 allele being associated with poorer prognosis. We investigated APOE allele distribution in acute stroke and the effect of the epsilon4 allele on outcome. METHODS: APOE genotypes were determined in 714 stroke patients: 640 ischemic stroke and 74 intracerebral hemorrhage patients. The survival effect of the epsilon4 allele was assessed with the use of a stratified log-rank test. A Cox proportional hazards regression model was used to estimate the independent effect of epsilon4 dose (0, 1, or 2) on survival, and logistic regression was used to determine the effect on 3-month outcome (good if alive at home, poor if in care or dead). RESULTS: Allele distribution matched the general population with no difference between the ischemic and hemorrhagic groups. Survival in the entire cohort was unaffected by epsilon4 dose. Improved survival with increasing epsilon4 dose was found in the ischemic group (relative hazard=0.76 per allele; P=0.04). If transient ischemic attacks were excluded, a trend for improved survival persisted (P=0.06). With intracerebral hemorrhage, a trend was seen toward reduced survival with epsilon4 (P=0.07, log-rank test). Three-month outcome in the ischemic group was unaffected by epsilon4 dose, and a trend toward poorer outcome with epsilon4 was seen for intracerebral hemorrhage (P=0.10). CONCLUSIONS: The APOE epsilon4 allele had divergent effects on survival and outcome in ischemic and hemorrhagic strokes in this population. The reported adverse effect on patients with intracerebral hemorrhage was supported. The favorable survival effect on ischemic stroke patients requires further study. 相似文献
998.
JR Nery D Weppler M Rodriguez P Ruiz ER Schiff AG Tzakis 《Canadian Metallurgical Quarterly》1998,65(12):1615-1621
BACKGROUND: Indication of liver transplantation for patients infected with hepatitis B virus (HBV) remains controversial because of the high incidence of posttransplant HBV recurrence and aggressive involvement of the allograft. In this article, we provide evidence that the introduction of lamivudine may favorably alter the prognosis of these patients. METHODS: Lamivudine was used in 40 HBV-infected adult patients suffering from chronic end-stage liver disease who underwent liver transplantation. The drug was used in the following settings: failure of prolonged passive immunoprophylaxis, elective conversion from immunoprophylaxis, de novo posttransplant HBV infection, and primary treatment with lamivudine which started before and continued after transplantation. Twenty patients (50%) had viral replication at the time lamivudine was started. Posttransplant and antiviral treatment follow-ups were 8-64 months (median follow-up: 27.5 months) and 9-39 months (median follow-up: 19 months), respectively. RESULTS: The patient and graft survival rates were 97.5% (39/40). Thirty-three patients (82.5%) have remained free of viral recurrence. In the seven re-infected patients, the manifestations of HBV involvement of the allograft have been mild. There have been no side effects related to lamivudine, and the treatment is substantially less costly than with other anti-HBV agents. CONCLUSIONS: Compared with historic series utilizing other modalities of treatment, the use of lamivudine has, so far, yielded superior results. This drug may be an important acquisition for antiviral prophylaxis in HBV-infected liver recipients. Because of the risk of viral mutations, however, efforts should proceed to achieve more efficacious methods for prevention and control of HBV recurrence. 相似文献
999.
AG Tielens 《Canadian Metallurgical Quarterly》1997,25(1):127-131
We have studied the role of cytokines in the spontaneous regression of AK-5 histiocytoma in syngeneic rats. Animals in which the tumour regresses show high levels of cytokines in the serum compared with animals which succumb to the tumour, and levels of IL-2, IL-4, IL-12, interferon-gamma (IFN-gamma) and tumour necrosis factor-alpha (TNF-alpha) are significantly higher in tumour tissue of the former. Thus there is an association between rejection of the tumour and the levels of cytokines present in the tumour mass. Our results also suggest a predominant Th1-type of response in those rats that display early tumour rejection. 相似文献
1000.