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191.
AL Gutiérrez-Escolano F Medina VR Racaniello RM Del Angel 《Canadian Metallurgical Quarterly》1997,227(2):505-508
Specific polyclonal antibody was raised against D-aspartate (D-Asp) which had been conjugated to glutaraldehyde and was purified by affinity chromatography. Immunohistochemical staining of rat pineal gland with the antibody demonstrated the presence of D-Asp in the cytoplasm of pinealocytes, the predominant cell type in this gland. D-Asp immunoreactivity was more evident in the distal region than in the proximal region of the gland. Pinealocytes in the distal region are presumably involved in the synthesis and secretion of the pineal hormone, melatonin, and the results of staining may indicate some yet unknown role of D-Asp in the regulation of melatonin secretion. 相似文献
192.
AL Escobar P Velez AM Kim F Cifuentes M Fill JL Vergara 《Canadian Metallurgical Quarterly》1997,434(5):615-631
We describe a high temporal resolution confocal spot microfluorimetry setup which makes possible the detection of fluorescence transients elicited by Ca2+ indicators in response to large (50-200 microM), short duration (< 100 ns), free [Ca2+] transients generated by laser flash photolysis of DM-nitrophen (DM-n; caged Ca2+). The equilibrium and kinetic properties of the commercially available indicators Fluo-3, Rhod-2, CalciumOrange-5N (COr-5N) and CalciumGreen-2 (CGr-2) were determined experimentally. The data reveal that COr-5N displays simple, fast response kinetics while, in contrast, Fluo-3, Rhod-2 and CGr-2 are characterized by significantly slower kinetic properties. These latter indicators may be unsuitable for tracking Ca2+ signaling events lasting only a few milliseconds. A model which accurately predicts the time course of fluorescence transients in response to rapid free [Ca2+] changes was developed. Experimental data and model predictions concur only when the association rate constant of DM-n is approximately 20 times faster than previously reported. This work establishes a quantitative theoretical framework for the study of fast Ca2+ signaling events and the use of flash photolysis in cells and model systems. 相似文献
193.
194.
AL Kraus 《Canadian Metallurgical Quarterly》1997,210(10):1412-1413
195.
JA Rivera C Fernández-del Castillo M Pins CC Compton KB Lewandrowski DW Rattner AL Warshaw 《Canadian Metallurgical Quarterly》1997,225(6):637-44; discussion 644-6
OBJECTIVE: The purpose of the study is to review a single institutional experience with mucinous ductal ectasia (MDE) and intraductal papillary neoplasms (IPNs) and to compare the clinicopathologic features of the two groups of tumors. SUMMARY BACKGROUND DATA: Mucinous ductal ectasia and IPNs represent newly recognized categories of pancreatic exocrine tumors, previously confused with pancreatic cystic neoplasms. The natural history of MDE and IPN is not well understood, and it is unclear whether MDE and IPN represent two distinct tumors or the same clinicopathologic entity. METHODS: The authors reviewed the clinical presentation, treatment, histopathology, and outcomes of 23 patients diagnosed with MDE or IPN at their institution over the past 6 years. RESULTS: The mean age at presentation for the cohort of patients with MDE and IPN was 62.5 years. The prevalence of abdominal pain was 75%, jaundice 25%, weight loss 42%, steatorrhea 37.5%, diabetes 37.5%, and history of pencreatitis 29%. Serum CA 19-9 levels ranged from 0 to 5350 units/mL with high levels reflecting advanced disease. There were no significant differences between MDE and IPN with respect to these parameters. Both MDE and IPN comprised papillary villous epithelial neoplasms involving the main and large pancreatic ducts. The tumors ranged from a few millimeters in size to panductal and were distinguished easily from cystic neoplasms in all cases. Invasive carcinoma was present in 11 (46%) of 24 patients, carcinoma in situ in an additional 10 (42%) of 24 patients, and low grade dysplasia in the remaining 3 (12%) of 24 patients. Mucinous ductal ectasia and IPN differed histopathologically only in degree of mucin secretion and tumor location. Mucinous ductal ectasia, but not IPN, was characteristically mucin-hypersecreting and more frequently involved the head of the gland than did IPN (11/16 vs. 1/8 p < 0.04). All patients were explored surgically and 20 (83%) of 24 of the tumors were resectable with frozen section control of the duct margins (9 pancreatoduodenectomies, 4 distal pencreatectomies, 7 total pancreatectomies). Despite the 88% prevalence of cancer, the overall survival at a mean follow-up of 21 months was 13 (87%) of 15 for MDE and 5 (71%) of 7 for IPN. CONCLUSIONS: Intraductal papillary neoplasms with or without MDE represent a spectrum of main duct papillary tumors ranging from adenoma to carcinoma with differing amounts of extracellular mucin production. Malignant IPNs with or without MDE typically exhibit extensive intraductal growth but are slow to invade the periductal tissues and slow to metastasize. The majority of patients with these tumors have resectable disease and a favorable prognosis; endoscopic therapy is inappropriate. The encompessing term intraductal papillary-mucinous tumors is appropriate. 相似文献
196.
This article discusses immunization, development, vision, blood pressure, dentition, behavioral, and environmental screening for preschool children. The authors then discuss screening for children in the early school years. Injury and violence prevention and topics of sexuality for the preadolescent are also presented. 相似文献
197.
HG Roozen AL Deden AJ Kerkhof JP Vorsteveld W van den Brink 《Canadian Metallurgical Quarterly》1997,141(49):2377-2380
Rapid opiate withdrawal and relapse prevention in opiate addicts are made possible by naltrexone, clonidine and diazepam in combination with cognitive behavioural therapy according to the Community Reinforcement Approach. In an open pilot experiment 12 addicted patients achieved initial detoxification. At follow-up after a minimum of 6 months, 10 of these had not relapsed. Good results with this detoxification method could be booked by selecting highly motivated opiate addicts. 相似文献
198.
199.
MP Saunders AJ Salisbury KJ O'Byrne L Long RM Whitehouse DC Talbot EB Mawer AL Harris 《Canadian Metallurgical Quarterly》1997,82(12):4044-4048
The treatment of cancer patients with conventional chemotherapy is sometimes associated with severe systemic toxicity and only a minimal survival benefit. Because of this, new less toxic and more efficacious treatments have been sought. 8-Chloro-cAMP (8-Cl-cAMP) is one of a new generation of anticancer drugs that act at the level of signal transduction. In preclinical models, 8-Cl-cAMP modulates protein kinase A (PKA) leading to growth inhibition and increased differentiation of cancer cells. 8-Cl-cAMP was given to 16 patients with advanced cancer as an infusion via an indwelling subclavian venous catheter. We showed that 8-Cl-cAMP had a parathyroid hormone-like effect leading to increased synthesis of renal 1,25-dihydroxyvitamin D [up to 14 times the baseline value, median 3.6 times; P = 0.00001 (Student's paired t test)]. This produced the dose-limiting toxicity of reversible hypercalcemia that could not be controlled by the administration of either pamidronate or dexamethasone. The treatment was otherwise well tolerated, and other cAMP-dependent pathways (cortisol and TSH) were not affected, emphasizing the marked differences between organs in their sensitivity to this cAMP analog. Our results have shown that 8-Cl-cAMP is biologically active, and it is feasible that if the hypercalcemia can be controlled, then this drug may have a role as a single agent, or as a short infusion between cycles of chemotherapy. 相似文献
200.