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171.
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FO Zelaya SE Rose PF Nixon BT Wholohan AJ Bower C Zimitat J Schoutrop DM Doddrell 《Canadian Metallurgical Quarterly》1995,13(4):555-561
Contrast-enhanced T1-weighted spin-echo magnetic resonance imaging (MRI) has demonstrated that Gd-diethylenetriaminepentaacetate (Gd-DTPA), which normally does not cross the blood-brain or blood-CSF barriers, does so approximately 40 min after administration of glucose to a vitamin B1 deficient rat. The period of the onset of this blood-CSF or blood-brain barrier dysfunction coincides with our previous observations of accumulation of glutamate or glutamate derivatives following an equivalent glucose load under identical conditions of thiamin deficiency, consistent with a relationship between these two observations. The dysfunction was reversed when a thiamin deficient animal was made thiamin replete. 相似文献
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The pancreas is an ideal organ for adenoviral gene therapy because of the high level of gene transfer that can be achieved and because of the many diseases that can potentially be treated using this technology. In this report, we characterize the immune response to direct pancreatic injection of adenovirus and we overcome some of the limitations it imposes by using immunosuppression. Direct injection of recombinant adenovirus into the pancreas leads to the production of neutralizing antibodies and to sensitized splenocytes which engage in increased cytotoxic, lymphoproliferative, and cytokine release activity when reexposed to adenovirus. Transgene expression is transient and the vector cannot be readministered. Deletion of CD4+ T helper cells improves expression over time (40% of pancreatic cells express transgene at day 28 vs. 5% in controls), and allows the vector to be readministered in the pancreas, albeit, inefficiently, when compared to naive animals. Similarly, blockade of CD40 ligand, which preserves the CD4+ T helper cell population, also improves expression over time (30% of pancreatic cells express transgene at day 28), and allows the vector to be readministered. With both approaches, neutralizing antibodies are decreased and the remaining splenocytes do not engage in activated immune responses. Thus, local delivery of the adenoviral vector induces a systemic response that prevents pancreatic readministration, even with direct injection. Blockade of CD40 ligand and T helper cell depletion are transient regimens that induce systemic immunosuppression. Until the development of newer strategies that selectively suppress adenoviral immune responses, these are viable alternatives for enhancement of pancreatic adenoviral delivery. 相似文献
176.
SE Melberg 《Canadian Metallurgical Quarterly》1997,28(11):47-48
Although many facilities believe turning over some patient care to unlicensed caregivers will cut costs, results show otherwise. The greater the rate of change--patient acuity--the greater the need for an all-RN staff. Skill mix, length of stay and salary costs among five teaching hospitals measure the cost effects. 相似文献
177.
SE Linnville 《Canadian Metallurgical Quarterly》1995,81(1):209-210
The indications for prolonged cardiopulmonary support or extracorporeal membrane oxygenation are expanding. A potential serious complication of these techniques is distal limb ischemia. Techniques have been developed to provide the distal limb with blood flow. Unfortunately, specialized skills and materials are required. We describe a simple method of providing distal limb perfusion using ordinary pressure tubing and a standard cordis catheter. This technique is capable of reproducing normal superficial femoral artery blood flow. 相似文献
178.
This randomized, double-blind, placebo-controlled study was aimed at detecting cerebrovascular effects of isradipine and enalapril in patients with moderate hypertension depending on the presence and grade on unilateral stenosis of internal carotid artery (ICA). We evaluated carotid vascular resistance by using Doppler analysis and regional cerebral blood flow (rCBF) by using 133Xe-clearance technique before and after a single 5-mg oral dose of isradipine, enalapril, or placebo. Their effects were randomly and consecutively tested in 73 patients with essential hypertension subdivided into three groups: without carotid occlusive lesions, with moderate (50-75%), and with severe (76-99%) unilateral asymptomatic ICA stenosis. There were no differences in age, gender, and antihypertensive effects of the drugs between these three subgroups. Three major variants of cerebrovascular drug effects were observed: absence of changes (variant I), decrease in carotid vascular resistance with increase in rCBF and elimination of side-to-side asymmetry (variant II), and increase in carotid vascular resistance with further reduction of rCBF ipsilaterally ICA stenosis, and increased side-to-side asymmetry (variant III). Frequency of variant III was significantly higher in patients with severe ICA stenosis. Enalapril produced variant I of cerebrovascular effects in most patients examined; variant III was observed only in 13% of patients with severe ICA stenosis. Isradipine produced variant I of cerebrovascular effects much less frequently than did enalapril. For this drug, variant II was most typical in patients without ICA stenosis and with moderate ICA stenosis. In 43.5% of patients with severe ICA stenosis, however, isradipine produced reduction of cerebral perfusion. Presumably the presence of ICA stenosis, especially >75%, increases the risk of cerebrovascular disorders in antihypertensive therapy. In patients with severe ICA stenosis, treatment with enalapril appears to be safer than that with isradipine. 相似文献
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RM Conry AF LoBuglio F Loechel SE Moore LA Sumerel DL Barlow J Pike DT Curiel 《Canadian Metallurgical Quarterly》1995,2(1):33-38
Congenital cataract, type Volkmann (McKusick no 115665, gene symbol CCV) is an autosomal dominant eye disease. The disease is characterized by a progressive, central and zonular cataract, with opacities both in the embryonic, fetal and juvenile nucleus and around the anterior and posterior Y-suture. We examined blood samples from 91 members of a Danish pedigree comprising 426 members, by using highly informative short tandem repeat polymorphisms and found the closest linkage of the disease gene (CCV) to a (CA)n dinucleotide repeat polymorphism at locus D1S243 (Zmax = 14.04 at theta M = 0.025 theta F = 0.000), at a penetrance of 0.90. Using two additional chromosome 1 markers, we were able to map the CCV gene in the sequence 1pter-(CCV, D1S243)-D1S468-D1S214. The (enolase 1) gene has been mapped to this area; however, a mutation described in this gene did not give eye disease. 相似文献