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51.
This study explored the relationship between adenine nucleotide levels in canine renal cortex and renal function following: (a) graded periods of warm ischemia; (b) 48 hours' flush cooling with electrolyte solutions and ice storage; and (c) continuous hypothermic perfusion. Exposure to normothermic ischemia resulted in a rapid (within 15 minutes) degradation of ATP to ADP and AMP as well as a slow decline in total adenine nucleotide (TAN) to levels which were proportional to the duration of the ischemic injury. No functional impairment was evident after 15 minutes' ischemia, but with longer times, both the extent of decline in TAN and the degree of recovery following restoration of blood flow could be used to predict the quality of renal function.The relationship between TAN levels and function was of less predictive value following cold storage or continuous perfusion. The efficacy of intracellular flush solutions could not be attributed solely to conservation of TAN, nor did the well-maintained TAN levels during continuous perfusion necessarily lead to significantly better 48-hour storage than flush cooling with C2 solution.
Résumé Cette étude faite chez le chien examine la corrélation entre la fonction rénale et le taux d'adénine nucléotide dans le cortex rénal suite à: 1) différentes périodes d'ischémic chaude; 2) entreposage sur glace pendant 48 heures apres flushing avec des solutions électrolytiques; 3) hypotermie par perfusion continuelle. L'ischémie chaude a produit une dégradation rapide de l'ATD en ADP et AMP (en moins de 15 minutes) et une diminution progressive de la quantité totale d'adénine nucléotide (TAN) proportioneile à la durée de la période ischémique. La fonction rénale n'a pas été affectée par des périodes d'ischémie de 15 minutes ou moins. Suite à des périodes ischémiques plus longues cependant, la chutte des taux de TAN et leur niveau de rétablissement après réouverture de la circulation sanguine ont permis de prédire la qualité de la fonction rénale. Après storage au froid ou perfusion continue, la relation entre les taux de TAN et la fonction rénale est disparue. Le flushing à l'aide des solutions de type intracellulaire, malgré sa faible capacité à conserver les taux de TAN s'est avéré une méthode d'entreposage aussi efficace que la perfusion continuelle, laquelle a maintenu des taux normaux de TAN.


Supported by Veterans Administration Research Grant 1519-01.  相似文献   
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Multiple endocrine neoplasia type I (MEN-I) is an autosomal dominant disorder characterized by endocrinopathies involving the anterior pituitary gland, parathyroid glands, and pancreas. The long-term prognosis for patients affected with this disorder is uncertain. To better characterize this prognosis, we performed a retrospective review of all patients with MEN-I treated at a single institution during the period 1951–1997. A group of 233 patients served as the study population. Their records were analyzed for confirmation of diagnosis, treatments received, long-term survival, and cause of death. Altogether, 108 eight male patients (46%) and 125 female patients (54%) were identified. At the conclusion of the study, 164 (70%) were alive and 69 (30%) were deceased, with a median follow-up for patients alive at last contact of 13.4 years (range < 1 month to 54.3 years). The cause of death was reliably obtained in 60 patients. Of these patients, 17 (28%) died of causes related to MEN-I, most commonly metastatic islet cell tumors (10 patients). The remaining patients died of causes unrelated to MEN-I, most commonly coronary artery disease and nonendocrine malignancies (14% each). The overall 20-year survival of MEN-I patients was 64% (95% CI was 56–72%), and that of an age- and gender-matched upper Midwest population was 81% (p < 0.001). Patients with MEN-I appear to be at increased risk of premature death. Earlier diagnosis and treatment of potentially malignant pancreatic islet cell neoplasms may result in a decrease of this premature mortality.  相似文献   
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OBJECTIVE: Our goal was to evaluate the role of intraoperative cystoscopy during surgery for pelvic organ prolapse and urinary incontinence. STUDY DESIGN: Charts of 224 consecutive patients who had intraoperative cystoscopy performed after urogynecologic surgery were reviewed. RESULTS: Nine injuries occurred that were unsuspected before cystoscopy, for an incidence of 4%. Six ureteral ligations occurred, four after Burch cystourethropexy and two after vaginal culdoplasty. Intravesical sutures were noted after two Burch procedures, and another injury occurred with passage of fascia lata through the bladder during a pubovaginal sling procedure. Eight injuries were managed by removal and replacement of the suture or sling with only one requiring ureteroneocystotomy. When patients with injuries were compared with those without, there were no statistical differences in demographic or surgical parameters. CONCLUSIONS: The potential for damage to the lower urinary tract is significant with complex urogynecologic surgery. Because of the increased and delayed morbidity associated with unrecognized injury, intraoperative surveillance cystoscopy should be considered a part of all such procedures.(Am J Obstet Gynecol 1997;177:71)  相似文献   
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The objective of this study was to examine the effects of the intakeof dietary fat upon colorectal cancer risk in a combined analysis of datafrom 13 case-control studies previously conducted in populations withdiffering colorectal cancer rates and dietary practices. Original datarecords for 5,287 cases of colorectal cancer and 10,470 controls werecombined. Logistic regression analysis was used to estimate odds ratios (OR)for intakes of total energy, total fat and its components, and cholesterol.Positive associations with energy intake were observed for 11 of the 13studies. However, there was little, if any, evidence of anyenergy-independent effect of either total fat with ORs of 1.00, 0.95, 1.01,1.02, and 0.92 for quintiles of residuals of total fat intake (P trend =0.67) or for saturated fat with ORs of 1.00, 1.08, 1.06, 1.21, and 1.06 (Ptrend = 0.39). The analysis suggests that, among these case-control studies,there is no energy-independent association between dietary fat intake andrisk of colorectal cancer. It also suggests that simple substitution of fatby other sources of calories is unlikely to reduce meaningfully the risk ofcolorectal cancer.  相似文献   
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Fumonisin mycotoxicosis in pigs causes a decrease in mean aortic pressure, an increase in mean pulmonary arterial pressure, and increases in serum concentrations of sphinganine (3.2 microM) and sphingosine (1.4 microM). To determine a causal relationship between the hemodynamic changes and sphingolipid alterations, we examined the in vitro effects of sphinganine, sphingosine, and sphingosine-1-phosphate on porcine aortic and pulmonary arterial rings. Both sphinganine and sphingosine relaxed un-contracted and phenylephrine-contracted aortic rings at > or = 10 microM and > or = 1 microM, respectively. Sphingosine (> or = 10 microM) relaxed un-contracted and phenylephrine-contracted pulmonary arterial rings, whereas sphingosine-1-phosphate (10 microM) contracted pulmonary arterial rings. Sphingosine (3 microM) also impaired the contractile response of pulmonary artery rings to 60 mM KCl. The results suggested that the systemic hypotension caused by fumonisin is mediated, in part, by increases in serum sphinganine and sphingosine concentrations, and the pulmonary hypertension is mediated, in part, by increased sphingosine-1-phosphate concentrations.  相似文献   
60.
Endometrial carcinomas are classified by their morphology into two major subtypes. Endometrioid carcinomas (type I) are generally estrogen dependent, well-differentiated, superficially invasive, and have a good outcome. Serous carcinomas (type II) are hormone independent, frequently deeply invasive and widely metastatic, and have a poor prognosis. Microarray technology and analysis allows us to determine if the global gene expression profiles of these two subtypes correlate with their morphologic phenotype. Fresh tissue from 18 endometrial carcinomas was studied: 7 well-, 2 moderately, and one poorly differentiated endometrioid, 4 serous carcinomas, and 4 high-grade mixed endometrioid-serous carcinomas. Labeled cDNA probes were synthesized (Cy5 for tumor, Cy3 for reference) and applied to microarrays containing 18,098 cDNA clones or ESTs. A pool of equal amounts of total RNA from each tumor served as the reference RNA. By unsupervised cluster analysis, the endometrioid carcinomas clustered together and were separate from the serous carcinomas. The high-grade mixed carcinomas clustered with the serous carcinomas. Using a statistical algorithm based on gene expression pattern and conducting a supervised analysis of the two defined groups, we have identified 315 genes that statistically differentiate type I from type II endometrial carcinomas. In addition to corroborating the predicted overexpression of known markers (e.g., ras and catenin in endometrioid carcinomas), the cDNA microarray technique has revealed novel alterations in gene expression relevant to cell cycle, cell adhesion, signal transduction, apoptosis, and tumor progression not previously implicated in endometrial carcinomas. For serous carcinomas, these include aldolase, desmoplakin, integrin-linked kinase, PKC, and metallopeptidase. In conclusion, the gene expression profiles of type I and type II endometrial carcinomas are different. Refinement of these profiles will permit more accurate diagnostic tumor classification and the development of prognosis assays.  相似文献   
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