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101.
102.
M Aristegui RF Canalis M Naguib E Saleh Y Cokkeser F Mancini M Sanna 《Canadian Metallurgical Quarterly》1997,76(8):578-583
We report our experience (1987-1993) with Meniere's disease patients treated with a retrolabyrinthine vestibular neurectomy. The current literature was reviewed and our results have been compared with those of previous reports. The overall success rate for vertigo relief was 96.7%, with no serious or permanent complications resulting from the procedure. The technical elements of the operation, as they apply to our approach and those of others, have been analyzed, with special attention given to the anatomical features of the region and their influence on success or failure. We conclude that the retrolabyrinthine approach for vestibular nerve section remains a safe and highly successful technique which merits continued use. 相似文献
103.
M van der Gaag AJ Debets HD Osiewacz RF Hoekstra 《Canadian Metallurgical Quarterly》1998,258(5):521-529
We have investigated the properties of the newly synthesized proton-pump inhibitor, 3-butyryl-8-methoxy-4-[(2-thiophenyl)amino]quinoline (YJA20379-6), on gastric mucosal proton-pump (H+/K+-ATPase) activity, gastric acid secretion and gastroduodenal lesions in experimental rats. YJA20379-6 markedly inhibited H+/K+-ATPase activity in rabbit isolated gastric mucosal microsomes, confirming its classification as a proton-pump inhibitor. The inhibitory efficacy of YJA20379-6 on the proton pump was approximately 14-times higher than that of omeprazole at pH 7.4. YJA20379-6 given intraduodenally had a potent inhibitory effect on gastric secretion in pylorus-ligated rats (ED50 22.9 mg kg(-1)) but was less active than omeprazole. Pretreatment of rats with YJA20379-6 dose-dependently protected the gastric mucosa from damage induced by water-immersion stress, indomethacin and absolute ethanol, and the duodenal mucosa from damage induced by mepirizole. Repeated administration of YJA20379-6 also dose-dependently accelerated the spontaneous healing of acetic acid-induced gastric ulcers. These results suggest that YJA20379-6 has potent anti-secretory and anti-ulcer effects which are exerted by suppression of H+/K+-ATPase activity in gastric parietal cells. YJA20379-6 might be useful for the clinical treatment of peptic ulcer diseases. 相似文献
104.
RE Marc RF Murry SK Fisher KA Linberg GP Lewis M Kalloniatis 《Canadian Metallurgical Quarterly》1998,39(9):1685-1693
PURPOSE: To establish a nomogram of amino acid signatures in normal neurons, glia, and retinal pigment epithelium (RPE) of the cat retina, guided by the premise that micromolecular signatures reflect cellular identity and metabolic integrity. The long-range objective was to provide techniques to detect subtle aberrations in cellular metabolism engendered by model interventions such as focal retinal detachment. METHODS: High-performance immunochemical mapping, image registration, and quantitative pattern recognition were combined to analyze the amino acid contents of virtually all cell types in serial 200-nm sections of normal cat retina. RESULTS: The cellular cohorts of the cat retina formed 14 separable biochemical theme classes. The photoreceptor --> bipolar cell --> ganglion cell pathway was composed of six classes, each possessing a characteristic glutamate signature. Amacrine cells could be grouped into two glycine- and three gamma-aminobutyric acid (GABA)-dominated populations. Horizontal cells possessed a distinctive GABA-rich signature completely separate from that of amacrine cells. A stable taurine-glutamine signature defined Müller cells, and a broad-spectrum aspartate-glutamate-taurine-glutamine signature was present in the normal RPE. CONCLUSIONS: In this study, basic micromolecular signatures were established for cat retina, and multiple metabolic subtypes were identified for each neurochemical class. It was shown that virtually all neuronal space can be accounted for by cells bearing characteristic glutamate, GABA, or glycine signatures. The resultant signature matrix constitutes a nomogram for assessing cellular responses to experimental challenges in disease models. 相似文献
105.
106.
D Olde Weghuis ME Stoepker B de Leeuw E van den Berg RF Suijkerbuijk WM Molenaar B de Jong A Geurts van Kessel 《Canadian Metallurgical Quarterly》1994,9(4):288-291
In this case-control study, we investigated the role of Cryptosporidium in gastroenteritis in children < 6 years old. Six hundred fresh stool specimens were examined for various pathogenic parasites, bacteria, and rotaviruses. Wet-mount preparations, formaline-ether concentrations, and Sheather's floatation techniques were used to recover the parasite oocysts. Permanent stained slides using acid-fast stain and trichrome stains were prepared. Of 300 children with gastroenteritis symptoms, 20 (6.7%) had Cryptosporidium oocysts; seven of the 20 had concomitant infections so they were excluded from the counts. This infection rate is significantly different (Z = 2; p < 0.05) from that found in the control group (1.7%) of children who reported no symptoms. The most frequent symptoms reported beside diarrhea were abdominal pain, cramps, anorexia, nausea, vomiting, and fatigue. Contaminated drinking water is suspected to be the source of infection; other possible factors are discussed. 相似文献
107.
108.
JM Robbins JM Tilford RF Jacobs JG Wheeler SR Gillaspy GE Schutze 《Canadian Metallurgical Quarterly》1998,152(4):358-366
OBJECTIVES: To estimate how many infants in selected high-risk subgroups would require treatment with respiratory syncytial virus immune globulin (RSV-IG) to avoid 1 hospital admission and to determine whether this is economically justified. DESIGN: Cost-benefit analysis. Data from 3 randomized controlled trials of RSV-IG are used to estimate the number needed to treat to prevent 1 hospital admission for respiratory syncytial virus infection. The threshold number needed to treat is computed according to a formula incorporating costs and benefits of RSV-IG prophylaxis. Estimates of the willingness to pay were obtained from a sample of 39 health care providers (35 physicians and 4 nurses). MAIN OUTCOME MEASURES: The number needed to treat to prevent 1 hospital admission for respiratory syncytial virus infection. The threshold number needed to treat that would balance costs with benefits. RESULTS: More than 16 (95% confidence interval, 12.5-23.8) infants would need to be treated with RSV-IG to avoid 1 hospital admission for respiratory syncytial virus infection, ranging from 63 for premature infants without chronic lung disease to 12 (confidence interval, 6.3-100.0) for infants with bronchopulmonary dysplasia. A sensitivity analysis of the costs and values of hospital admission for respiratory syncytial virus infection and RSV-IG treatment resulted in a weak recommendation against the treatment of infants with bronchopulmonary dysplasia and strong recommendations that the costs and risks of RSV-IG treatment outweigh the benefits for the combined sample of infants and premature infants without lung disease. CONCLUSIONS: The number-needed-to-treat procedures offer a method to assess evidence of treatment effects and decision rules for whether to accept treatment recommendations. Under plausible assumptions, treatment with RSV-IG is not recommended for infants without lung disease. Institutions can examine cost and benefit assumptions that best fit their own practice setting. 相似文献
109.
G Daidone B Maggio S Plescia D Raffa D Schillaci O Migliara A Caruso VM Cutuli M Amico-Roxas 《Canadian Metallurgical Quarterly》1998,53(5):350-356
Several new 1-methyl-5-[substituted-4-oxo-1,2,3-benzotriazin-3-yl] -1H-pyrazole-4-acetic acids and their ethyl ester derivatives were prepared. The compounds were tested for analgesic and antiinflammatory activities, acute toxicity, ulcerogenic effect, and as in vitro inhibitors of 3 alpha-hydroxysteroid dehydrogenase (3 alpha-HSD), since it is claimed that the inhibition of such an enzyme predicts in vivo antiinflammatory activity. Some compounds were more active than phenylbutazone in the phenylbenzoquinone and acetic acid peritonitis tests, and equiactive to the same drug in the carrageenin paw edema test. All the compounds inhibited the 3 alpha-HSD, but no correlation was observed with the paw edema inhibition values. The compounds proved to possess marginal or no ulcerogenic effect, as well as low systemic toxicity. 相似文献
110.
JL Clements B Yang SE Ross-Barta SL Eliason RF Hrstka RA Williamson GA Koretzky 《Canadian Metallurgical Quarterly》1998,281(5375):416-419
The leukocyte-specific adapter molecule SLP-76 (Src homology 2 domain-containing leukocyte protein of 76 kilodaltons) is rapidly phosphorylated on tyrosine residues after receptor ligation in several hematopoietically derived cell types. Mice made deficient for SLP-76 expression contained no peripheral T cells as a result of an early block in thymopoiesis. Macrophage and natural killer cell compartments were intact in SLP-76-deficient mice, despite SLP-76 expression in these lineages in wild-type mice. Thus, the SLP-76 adapter protein is required for normal thymocyte development and plays a crucial role in translating signals mediated by pre-T cell receptors into distal biochemical events. 相似文献