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111.
P Talard S Lévy J Bonal F Paganelli C Bouchiat G Cellarier GV Dussarat 《Canadian Metallurgical Quarterly》1996,19(8):1264-1267
Aborted sudden death as the presenting manifestation of hypertrophic cardiomyopathy in a 14-year-old child is reported. Documented ventricular fibrillation was the cause of cardiac arrest. No ventricular arrhythmia was induced during programmed electrical stimulation. An implantable cardioverter-defibrillator was indicated. As the patient had a family history of myocardial disease, he had undergone a cardiovascular evaluation 4 years before the major event, and was found normal. It is suggested that normal physical examination, ECG, echocardiogram should not rule out the diagnosis of hypertrophic cardiomyopathy when a family history is present. Left ventricular hypertrophy may develop during childhood in patients with hypertrophic cardiomyopathy. 相似文献
112.
K Triantafyllou GV Papatheodoridis GA Paspatis TH Vasilakaki I Elemenoglou DG Karamanolis 《Canadian Metallurgical Quarterly》1997,44(14):533-538
BACKGROUND/AIMS: In order to reduce the number of colonoscopies performed for the surveillance of patients after polypectomy, suitable predictors of adenomas recurrence are needed. The aim of this study was to find predictors of the early development of metachronous adenomas and specifically of advanced ones. MATERIALS AND METHODS: Forty-four patients underwent total colonoscopy 24-26 months after initial endoscopic polypectomy. All polyps were endoscopically removed and an adenoma was considered as advanced if the diameter was > 1 cm and/or villous component and/or severe dysplasia were present. RESULTS: Metachronous adenomas were detected in 16 (36.4% patients. Five (11.4%) of them had advanced metachronous adenomas. Early recurrence of adenomas was significantly correlated with the total number of indices adenomas (p = 0.027). On the contrary, the presence of metachronous adenomas was not related to any of the patients' characteristics nor to the site and the histology of the indices adenomas. The development of advanced metachronous adenomas during the same period was significantly correlated with patients' age, as it was observed only in patients aged > or = 60 years (5/21 or 23.8%) and in none of the patients aged < 60 years (Odds ratio: 15.7, p = 0.02). Logistic regression analysis revealed that patient's age was the only significant predictor of the early development of advanced metachronous adenomas (beta = 0.40, p = 0.02) and that the number of the indices adenomas was the only significant predictor for the recurrence of all adenomas (beta = 1.59, p = 0.02). CONCLUSIONS: 1. Only patients aged > or = 60 years seem to develop advanced metachronous adenomas two years after polypectomy and 2. The likelihood for developing metachronous adenomas during the same period is related to the number of indices adenomas. 相似文献
113.
GV Heller M Sridharan J Morse S Glasser CL Beach 《Canadian Metallurgical Quarterly》1997,17(4):760-766
STUDY OBJECTIVE: To determine the safety and efficacy of diltiazem CD 180 mg administered once/day in patients with chronic stable angina inadequately controlled with P-blockers, long-acting nitrates, or both. DESIGN: Multicenter, randomized, double-blind, placebo-controlled, parallel-group trial. SETTING: Medical clinics in the private and academic sectors. PATIENTS: Of 172 patients, 170 completed the 2-week double-blind treatment period. INTERVENTION:. Patients received either diltiazem CD 180 mg or placebo once/day in combination with existing antianginal therapy. MEASUREMENTS AND MAIN RESULTS: The time to termination of exercise tolerance testing, 24 hours after the dose increased significantly in the diltiazem CD group (37.2 sec) compared with the placebo group (21.3 sec, p=0.0438). Time to onset of angina during exercise testing also increased (57.6 vs 35.0 sec, respectively, p=0.0324), as did time to moderate angina (37.5 vs 20.6 sec, respectively, p=0.0354). The rates of total angina attacks and of angina attacks on exertion were significantly reduced in the diltiazem CD group versus placebo (p<0.05). Significant reductions in systolic and diastolic blood pressures and heart rate-blood pressure product measured at rest, submaximum exercise, and exercise termination were observed in diltiazem CD-treated patients compared with placebo (p<0.05). The frequency of treatment-related adverse events was identical in the two groups, 15.1%. CONCLUSION: Diltiazem CD 180 mg once/day is an effective, safe, and beneficial initial dosage when added to existing antianginal therapy. 相似文献
114.
TV Cacciarelli M Green R Jaffe GV Mazariegos A Jain JJ Fung J Reyes 《Canadian Metallurgical Quarterly》1998,66(8):1047-1052
BACKGROUND: Posttransplant lymphoproliferative disease (PTLD) after pediatric liver transplantation has been associated with high mortality rates. METHODS: The present study examined 282 consecutive pediatric liver transplant recipients from October 1989 to June 1996 who received primary tacrolimus immunosuppression. The aim was to determine the incidence of PTLD, management strategies, and patient outcome. RESULTS: The incidence of PTLD was 13% (361282) with a mean age of 5.5+/-0.7 years (range 0.6 to 15) at diagnosis. The average time from transplantation to PTLD was 10.1+/-2.1 months. Initial treatment of PTLD consisted of reduction (3 patients) or discontinuation (33 patients) of tacrolimus and initiation of antiviral therapy (intravenous ganciclovir, 14 patients; intravenous acyclovir, 22 patients; or both, 5 patients). Alpha-interferon was used in four patients (two successfully). One patient also received gamma-interferon, chemotherapy, and radiation for a central nervous system lesion. Chemotherapy was also used in one patient with Burkitt's, whereas one patient with a pulmonary lesion received additional radiation therapy. Three patients received supportive surgery for gastrointestinal involvement, and one patient had a splenectomy for hemolysis. Overall mortality was 22% (8/36) with 5 (14%) PTLD-related deaths (disseminated disease, 4 patients; bowel perforation, 1 patient). Of 31 survivors, 23 had acute rejection at a median time of 24 days after PTLD, with 2 patients developing chronic rejection. One patient required retransplantation. Present immunosuppression consists of tacrolimus monotherapy in 14 patients, tacrolimus/prednisone in 8 patients, and none in 6 patients. CONCLUSION: In summary, PTLD can be successfully treated with reduction of immunosuppression and administration of antiviral agents in most patients. The management of rejection after PTLD requires reassessment of disease status and judicious reintroduction of immunosuppression therapy. 相似文献
115.
VN Buneva OA Andrievskaia IV Romannikova GV Gololobov RP Iadav VI Iamkovo? GA Nevinski? 《Canadian Metallurgical Quarterly》1994,28(4):738-743
The interaction of antibodies from blood sera of patients with autoimmune pathology, systemic lupus erythematosus with oligoribonucleotides was studied. The RNA-hydrolyzing activity was shown to be an intrinsic property of autoantibodies. Enzymic activity of antibodies in hydrolysis of poly(U) was estimated at 20-40% of that of RNase A. In contrast to known eukaryotic RNases, the autoantibodies possess a specific RNA-hydrolyzing activity for oligo r(A). The RNA-nicking activity of antibodies in hydrolysis of oligoadenylates was more higher than with hydrolysis of oligo d(A). Optimal conditions of r(pA)13 hydrolysis were selected, including the optimal of pH = 8.7. 相似文献
116.
117.
In this study, the authors test for and estimate the clustering of marijuana use within United States neighborhoods, making use of data from annual nationally representative household sample surveys conducted during the period 1990-1995. A recently developed statistical method, alternating logistic regression, was used to quantify the clustering of marijuana users in neighborhoods. The resulting estimates of pairwise odds ratios ranged from 1.3 (95% confidence interval 1.22-1.42) for the lifetime history of marijuana use to 2.0 (95% confidence interval 1.6-2.6) for recent sharing of marijuana from one person to another. Exploratory analysis showed a slight decrease of clustering effects after adjustment for individual-level covariates: age, sex, race, education, annual family income, and history of tobacco use. Nevertheless, the main factors that account for clustering remain to be determined. Alternating logistic regression provided useful estimates of marijuana use clustering and can be used to estimate clustering of the other drug-related behavior, including sharing of needle injection equipment and other human immunodeficiency virus risk behaviors. As a form of multilevel analysis, the alternating logistic regression can accommodate shared, community-level characteristics that might influence drug taking (e.g., collective efficacy), as well as individual-level covariates, such as age and sex. 相似文献
118.
P Ure?a M Mannstadt M Hruby A Ferreira F Schmitt C Silve R Ardaillou B Lacour AB Abou-Samra GV Segre 《Canadian Metallurgical Quarterly》1995,47(6):1797-1805
In a recent study we demonstrated that the PTH/PTHrP receptor (PTH-R) mRNA was markedly down-regulated in the remnant kidney of uremic rats with severe secondary hyperparathyroidism. Among the factors potentially implicated in this down-regulation, to date only PTH has been demonstrated to modulate PTH-R expression. Here, we examined the effect of thyroparathyroidectomy (TPTX) on the renal expression of PTH-R in rats with normal renal function or with chronic renal failure (CRF) induced by 5/6 nephrectomy. Four groups of rats were studied: control, TPTX, CRF, and CRF + TPTX. Moderate-degree renal failure was documented by mean (+/- SD) creatinine clearances (microliter/min/100 g body wt) of 259 +/- 40 and 212 +/- 45 in CRF and CRF + TPTX rats, compared with 646 +/- 123 and 511 +/- 156 in control and TPTX rats, respectively. Plasma phosphorus, calcitriol, and ionized calcium were significantly lower in CRF and CRF + TPTX than in control animals. Plasma ionized calcium and calcitriol were also lower in TPTX than in control rats. Plasma PTH levels (pg/ml) were increased in CRF rats (41.8 +/- 29.4), and markedly decreased in TPTX (10.1 +/- 7.8) and CRF + TPTX (8.0 +/- 3.8) rats compared with control rats (21.7 +/- 7.5). Northern blot analysis showed that the level of the steady-state PTH-R mRNA in the kidney of CRF and CRF + TPTX rats was markedly decreased compared with that of control rats, the ratios of PTH-R mRNA/beta-actin mRNA being 0.28 +/- 0.04 and 0.27 +/- 0.03 versus 0.54 +/- 0.05, respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
119.
Carbon monoxide (CO) is an activator of soluble guanylyl cyclase and is implicated as a neuronal messenger. CO production, nitric oxide synthase (NOS) activity, and guanosine 3',5'-monophosphate (cGMP) levels were quantitated in cerebellar granule cell cultures. Metabolic labeling experiments enabled the direct measurement of neuronal CO production in vitro. CO production is significant, and peaked during early stages of culture. NOS activity and cGMP levels synchronously increased as cells matured. Whereas inhibition of NOS depleted cGMP in mature cultures, inhibitors of CO production potentiated the nitric oxide (NO)-mediated cGMP increase. Exogenous CO at similar concentrations to endogenous levels blocked the NO-mediated cGMP increase. These results directly demonstrate that endogenous neuronal CO production is high and indicate that while NO is the major regulator of cGMP in these neurons, CO may modulate the NO-cGMP signaling system. 相似文献
120.
JT Robertson GV Huffmon LB Thomas CW Leffler BC Gunter RP White 《Canadian Metallurgical Quarterly》1996,21(15):1731-1736
STUDY DESIGN: This study ascertained the effects of discectomy on prostaglandin synthesis. OBJECTIVES: The purpose of these novel experiments was to measure the levels of two prostaglandins in lumbar epidural fluid obtained from an area subjected to discectomy. For comparison, lumbar epidural fluid from a site not disturbed by discectomy and fluid from a subcutaneous site were analyzed for the prostaglandins. SUMMARY OF BACKGROUND DATA: Previous studies have shown that nuclear material obtained from degenerative discs manifests an extraordinarily high level of phospholipase A2 activity. Others have hypothesized that the known inflammatory effects of phospholipase A2 are due to the release of arachidonic acid, which is converted to various eicosanoids, including several algesic prostaglandins (PGI2 and PGE2). No previous study has continuously measured prostaglandin levels in epidural fluid or assessed the effect of discectomy on prostaglandin production. METHODS: An ultrafiltrate of lumbar epidural fluid of dogs was obtained from indwelling catheters located adjacent to spinal areas that were and were not subjected to discectomy as well as from subcutaneous tissue. The fluid was collected daily for 14 days and analyzed for PGE2 and 6-keto PGF1(alpha) (the stable metabolite of PGI2) by radioimmunoassay. RESULTS: The concentration of 6-keto PGF1(alpha) and PGE2 in fluid collected during the first 24 hours was significantly higher in the area of discectomy than in the epidural region that was not subjected to discectomy and significantly higher than in fluid obtained from the subcutaneous site. The high level of these prostaglandins at the discectomy site fell rapidly, so that by the end of 48 hours the differences in values between spinal fluid from the discectomy and nondiscectomy regions were not statistically significant. The concentration of the prostaglandins in epidural fluid decreased with time and became minimal within the second week. CONCLUSION: The removal of normal discs is accompanied for 24 hours by a marked rise in the synthesis of two prostaglandins known to produce pain. Because the concentration of prostaglandins in epidural fluid decreased rapidly thereafter, the initial surge obtained appears to be associated more with chemical factors such as phospholipase A2 than with wound healing. 相似文献