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131.
132.
Diltiazem, a calcium channel blocker, and a cardiovascular therapeutic agent offers significant protection to mice against lethal dose of ionizing radiation. Considering the potential efficacy of diltiazem as a radioprotector for human use, it was deemed necessary to investigate its influence on radiation-induced behavioural changes like nausea, vomiting, learning, memory and performance. In the present studies, conditioned taste aversion (CTA) test based on consumption of saccharin solution, was used as a marker of behavioural changes. Significant CTA (97 +/- 2%) was observed in rats irradiated with Co-60 gamma rays (absorbed dose 1 Gy). Administration of diltiazem at doses greater than 10 mg/kg, body wt, evoked CTA in a dose-dependent manner and that was found to be further aggravated on irradiation. At a lower dose of 5 mg/kg, body wt, diltiazem did not evoke CTA and protected against radiation induced aversion significantly (62 +/- 3%). The results suggest that diltiazem at concentrations lower than 10 mg/kg, body wt, in rats may be useful in preventing radiation induced behavioural changes. This observation could be of particular significance in clinical radiotherapy where radiation induced nausea and vomiting are of great concern. 相似文献
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134.
MC Hou TC Yen HC Lin BI Kuo CH Chen FY Lee RS Liu FY Chang SD Lee 《Canadian Metallurgical Quarterly》1997,92(10):1875-1878
OBJECTIVE: Endoscopic injection sclerotherapy and variceal ligation are two popular endoscopic methods used to treat esophageal variceal hemorrhage. These two methods have not been compared with regard to esophageal dysfunction after treatment. This is a prospective investigation of esophageal dysmotility after endoscopic injection sclerotherapy and variceal ligation. METHODS: Sequential changes of esophageal motility after endoscopic injection sclerotherapy (n = 25) and variceal ligation (n = 25) were investigated in 50 cirrhotic patients with recent variceal bleeding. Another 22 cirrhotics without esophageal varices were included as controls. Radionuclide esophageal transit tests were performed before initial endoscopic treatment, and 1 and 3 months after variceal eradication. RESULTS: The baseline esophageal transit time was longer in both the sclerotherapy (n = 25, 7.8 +/- 1.4 s) and ligation groups (n = 25, 8.2 +/- 1.8 s) than in controls (n = 22, 6.7 +/- 0.7 s, p < 0.005). The transit time was longer in patients with large varices than in those with small varices (8.3 +/- 1.7 vs. 7.2 +/- 0.7 s, p < 0.05). In the sclerotherapy group, the transit time was prolonged 1 month after variceal eradication, compared with its pretreatment state (n = 20, 7.6 +/- 1.5 vs. 10.0 +/- 2.2 s, p < 0.0001) but was shortened at 3 months compared with 1 month after variceal eradication (n = 12, 10.7 +/- 1.5 vs. 8.6 +/- 2.2 s, p < 0.05). Multiple regression analysis showed that the number of treatment sessions required to eradicate varices was the only significant factor associated with prolonged transit time (p < 0.05). In the ligation group, the transit time changed little at 1 month or 3 months after variceal eradication. CONCLUSIONS: Impairment of esophageal motility can be significant with endoscopic injection sclerotherapy but is reversible. However, endoscopic variceal ligation exerts no significant impact on esophageal motility. 相似文献
135.
OA Garden HC Rutgers SH S?rensen S Daniels D Walker RM Batt 《Canadian Metallurgical Quarterly》1997,63(3):257-261
We investigated the influence of nutrition and exercise interventions within cognitive/behavioral and public health formats on weight and blood lipid profiles in obese children. Compliance was also examined as well as the relationship of the compliance measures with clinical outcome variables. Three conditions were compared over 16 sessions: nutrition and eating-habit change followed by exercise (NE), exercise followed by nutrition and eating-habit change (EN), and an information control (INFO). NE and EN were presented in a cognitive/ behavioral framework which focused on the development of self-regulation whereas the INFO condition received the same material in a public health/educational model. NE and EN participants evidenced modest, yet significant, reductions in weight and blood lipids, and the impact of these two interventions endured at a five-year follow-up. In contrast, INFO participants displayed stable weight and blood lipids during the course of the program, and most remained morbidly obese at follow-up. Improved nutrition, increased physical activity and fitness were significantly correlated with weight and lipid reductions. 相似文献
136.
LJ Garcia TK Pradhan HC Weber TW Moody RT Jensen 《Canadian Metallurgical Quarterly》1997,1356(3):343-354
A magnetization-prepared sequence, T2-Prep-IR, exploits T1, T2, and chemical shift differences to suppress background tissues relative to arterial blood. The resulting flow-independent angiograms depict vessels with any orientation and flow velocity. No extrinsic contrast agent is required. Muscle is the dominant source of background signal in normal volunteers. However, long-T2 deep venous blood and nonvascular fluids such as edema also contribute background signal in some patients. Three sets of imaging parameters are described to address patient-specific contrast requirements. A rapid, spiral-based, three-dimensional readout is utilized to generate high-resolution angiograms of the lower extremities. Comparisons with x-ray angiography and two-dimensional time-of-flight angiography indicate that this flow-independent technique has unique capabilities to accurately depict stenoses and to visualize slow flow and in-plane vessels. 相似文献
137.
LH Carvalho CJ Fontes AA Fernandes HC Marinuzzi AU Krettli 《Canadian Metallurgical Quarterly》1997,19(2):47-59
The present review offers a new look at capillary isoelectric focusing (cIEF) by centering on the most troublesome aspects of the technique, namely: 1) how to modulate the slope of the pH gradient, for increasing resolution (equivalent to pH gradient engineering, as easily available in immobilized pH gradients); and 2) how to keep proteins in solution at (and in the proximity of) the pl value. A simple solution is offered in the first case: addition, to the standard 2-pH-units interval, of separators or spacers, i.e., of amphoteric molecules (either single or in combination) able to locally flatten the pH and increment resolution. Examples of the separation of fetal and glycated hemoglobins are provided. In the second case, a unique solubilization power (while maintaining full protein integrity and enzyme activity) is obtained if class I solubilizers are used. They consist of mixtures of sugars (e.g., sucrose and sorbitol) at ca. 1 M concentration, with zwitterions (up to 1 M) such as the class of nondetergent sulfobetaines, but also taurine and some of the Good's buffers (e.g., CAPS). In these solvents, the protein exists in a state of superhydration and its solubility is greatly augmented. The review ends with an excursus on the use of isoelectric buffers in zone electrophoretic separations. Such isoelectric buffers offer unique advantages: They permit very-high-voltage gradients (up to 1000 V/cm) and thus minimize analysis times (down to a few min in 30-35 cm long capillaries). This results in a marked increase in resolution, due to minimal diffusion-driven peak spreading. Such buffers are finding unique applications for generating peptide maps of tryptic digests of proteins and also in the analysis of oligonucleotides. 相似文献
138.
CA Benadiva O Davis I Kligman M Moomjy HC Liu Z Rosenwaks 《Canadian Metallurgical Quarterly》1997,67(4):724-727
OBJECTIVE: To evaluate the outcomes of IVF and the incidence of ovarian hyperstimulation syndrome (OHSS) after discontinuing gonadotropin therapy in patients at risk of developing OHSS by delaying hCG administration until a drop in serum E2 levels was observed. DESIGN: Retrospective study. SETTING: IVF program at a university center. INTERVENTIONS: Gonadotropin administration was withheld in 22 patients (group 1) when their serum E2 level was > or = 3,000 pg/mL (conversion factor to SI unit, 3.671). Patients continued GnRH analogue injections daily, and hCG was administered when serum E2 levels dropped to < or = 3,000 pg/mL. Outcomes were compared with 26 patients (group 2) in whom embryo transfer was canceled and all embryos cryopreserved for transfer during a subsequent unstimulated cycle. MAIN OUTCOME MEASURES: Outcomes of IVF and incidence of OHSS were compared in both groups of patients. In group 1, follicular and hormonal parameters before and after the coasting interval were compared in pregnant versus nonpregnant patients. In addition, serum hormonal profiles were evaluated daily during the coasting period to determine the effects of gonadotropin withdrawal. RESULTS: Although the mean number of oocytes retrieved was significantly higher in group 2, fertilization rates, miscarriage rates, delivery rates/stimulation cycle, and the incidence of OHSS did not differ significantly between the two groups. CONCLUSION: Withholding gonadotropin administration is an effective alternative to prevent the development of severe OHSS in a high-risk population. Although the risk of cancellation cannot be completely eliminated, this strategy can provide a high pregnancy rate without the need to repeat multiple frozen-thawed cycles. 相似文献
139.
Kortte Kathleen B.; Veiel Lori; Batten Sonja V.; Wegener Stephen T. 《Canadian Metallurgical Quarterly》2009,54(1):91
Objective: To establish psychometric properties of the Acceptance and Action Questionnaire (AAQ), a measure of avoidance, in medical rehabilitation populations. Study Design: Cross-sectional and longitudinal. Setting: Three acute, inpatient rehabilitation units. Participants: One hundred thirty-nine adults with spinal cord dysfunction, stroke, amputation, or orthopedic surgery. Measures: AAQ, Hope Scale, Spiritual Well-Being Scale, Positive and Negative Affect Scale, Brief Symptom Inventory, Hopkins Rehabilitation Engagement Rating Scale, Functional Independence Measure, Craig Handicap Assessment and Reporting Technique, Satisfaction with Life Scale. Results: The AAQ has adequate internal consistency (α = .70), is best understood with a two-factor solution, is positively correlated with depression (r = .36, p r = .41, p r = ?.51, p r = ?.33, p r = ?.32, p 相似文献
140.
BACKGROUND AND PURPOSE: A rapid but transient expression of c-fos after cerebral ischemia has been extensively documented. However, the mechanism of this induction and whether induction of c-fos is neuroprotective or detrimental to the brain after ischemia is presently not clear. Fasting before transient cerebral ischemia has been shown to reduce delayed neuronal necrosis and infarct volume. The purpose of the present study was to examine the effect of preischemic fasting for 24 hours on the expression of c-fos after transient focal cerebral ischemia. METHODS: Focal cerebral ischemia was induced by temporary occlusion of the right middle cerebral artery and both common carotid arteries for 60 minutes. Male Long-Evans rats weighting 250 to 300 g were randomly divided into two groups: fed (control group) and food deprived for 24 hours (fasted group) before ischemic surgery. Infarct volumes were measured on the basis of triphenyltetrazolium chloride-delineated infarct areas, and plasma glucose levels were determined by the glucose oxidase method. Temporal and spatial expression of c-fos was assessed by Northern blot analysis, in situ hybridization, and immunohistochemistry. RESULTS: Fasting for 24 hours before 60 minutes of ischemia resulted in a 26.6% decrease in preischemic plasma glucose levels and a 74.5% reduction in infarct volumes in the fasted group compared with the control group. A rapid but transient induction of c-fos mRNA was observed in the ischemic cortex in control animals after 60 minutes of ischemia. Fasting not only prolonged but also enhanced the intensity of c-fos expression in the ischemic cortex. Regional c-fos expression was also different between these two groups. CONCLUSIONS: The results support the contention that c-fos expression may be compatible with its purported neuroprotective role in selected experimental paradigms. The signaling mechanisms underlying the effect of fasting and subsequent lowering of plasma glucose levels on postischemic c-fos expression remain to be explored. 相似文献