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The present study was designed to determine if spinal calcium channels, calmodulin, and calcium/calmodulin-dependent protein kinase II were involved in the production of antinociception induced by cold water swimming stress (CWSS). The effects of intrathecal (i.t.) injection of nimodipine, omega-conotoxin GVIA, calmidazolium, or (S)-5-isoquinolinesulfonic acid, 4-[2-[(5-isoquinolinyl-sulfonyl)methylamino]-3-oxo-3-(4-phenyl-1-piperaz inyl)-propyl]phenyl ester (KN-62) on CWSS-induced antinociception were studied in ICR mice. The antinociception was assessed by the tail-flick test. CWSS produced inhibition of the tail-flick response. Various doses of nimodipine (10-40 ng), omega-conotoxin GVIA (5-40 ng), calmidazolium (10-40 ng), or KN-62 (5-40 ng) injected i.t. alone did not show any antinociceptive effect in the tail-flick test. I.t. pretreatment with omega-conotoxin GVIA, calmidazolium, or KN-62 dose dependently attenuated the CWSS-induced inhibition of the tail-flick response. However, i.t. pretreatment with nimodipine did not affect the inhibition of the tail-flick response induced by CWSS. Our results suggest that spinal N-type calcium channel, calmodulin and calcium/calmodulin-dependent protein kinase II may be involved in the production of antinociception induced by CWSS. On the other hand, CWSS-induced antinociception appears not to be mediated via the spinal L-type calcium channel. 相似文献
13.
The traditional approach to severe subglottic stenosis (SGS) in the pediatric age group is laryngotracheal reconstruction (LTR). This approach may be complex and multistaged, with variable and unpredictable success rates in the individual patient. Excellent results have been reported in adults who had severe SGS and underwent partial resection of the cricoid and primary thyrotracheal anastomosis. This procedure has not been widely reported in infants and children. We report our experience with this procedure in 16 pediatric patients with grade III or IV SGS. Eleven patients had multiple previous LTR operations. The preoperative evaluation, surgical techniques, postoperative care, complications, and final results are described and discussed. Fourteen patients were decannulated after the procedure, 1 patient needed a second open procedure prior to decannulation, and 1 patient with concomitant bronchopulmonary dysplasia remains cannulated, for an overall 94% decannulation rate. Fourteen patients have no limitation of respiration, and 1 patient has moderate exercise intolerance. The results of this series suggest that partial cricotracheal resection with primary anastomosis is a relatively safe and effective procedure for pediatric patients with severe SGS. 相似文献
14.
CS Rubenstein ZF Peynircioglu DL Chambless TA Pigott 《Canadian Metallurgical Quarterly》1993,31(8):759-765
In a series of experiments we extended the research on possible memory deficits in subclinical obsessive-compulsive Ss who reported excessive checking. Using a variety of memory tests we compared 20 subclinical checkers to 20 Ss without obsessive-compulsive symptomatology. Contrary to hypothesis, checkers remembered self-generated words better than read words just as much as did normals, but they were more likely than normals to report thinking they had studied words that, in fact, had not been on the study list. Further, they more often confused whether they read or generated the words at study. Checkers did not appear to perseverate on already-recalled words on repeated free recall tests any more than did normals. However, checkers remembered fewer actions overall and more often misremembered whether they had performed, observed, or written these actions. Such memory deficits may contribute to the development of excessive checking. 相似文献
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RG Wilde JT Billheimer SJ Germain EA Hausner PC Meunier DA Munzer JK Stoltenborg PJ Gillies DL Burcham SM Huang JD Klaczkiewicz SS Ko RR Wexler 《Canadian Metallurgical Quarterly》1996,4(9):1493-1513
Acyl-CoA:cholesterol acyltransferase (ACAT) is the enzyme largely responsible for intracellular cholesterol esterification. A systemic inhibitor of ACAT is believed to be able to slow or even reverse the atherosclerotic process. Towards that goal, a series of cyclic sulfides, derived from the hetero-Diels-Alder reaction of thioaldehydes with 1,3-dienes, and bearing carboxamide substituents, were prepared and evaluated for in vitro (in several tissues and species) and ex vivo ACAT inhibition. Minor changes in subsequent structure were found to have a significant effect in optimization of the biological activity of this series of compounds. 相似文献
17.
R Bascom J Kesavanathan TK Fitzgerald KH Cheng DL Swift 《Canadian Metallurgical Quarterly》1995,103(11):1026-1030
Nasal mucociliary clearance (NMC) is a biomarker of nasal mucosal function. Tobacco smokers have been shown to have abnormal NMC, but the acute effect of environmental tobacco smoke (ETS) on nonsmokers is unknown. This study evaluated acute tobacco smoke-induced alterations in NMC in 12 healthy adults. Subjects were studied on 2 days, separated by at least 1 week. Subjects underwent a 60-min controlled exposure at rest to air or sidestream tobacco smoke (SS) (15 ppm CO) in a controlled environmental chamber. One hour after the exposure, 99mTc-sulfur colloid was aerosolized throughout the nasal passage and counts were measured with a scintillation detector. Six out of 12 subjects showed more rapid clearance after smoke exposure than after air exposure, and 3/12 had rapid clearance on both days. However, substantial decreases in clearance occurred in 3/12 subjects, all of whom had a history of ETS rhinitis. In two subjects, more than 90% of the tracer remained 1 hr after tracer administration (2 hr after smoke exposure). Understanding the basis for biologic variability in the acute effect of tobacco smoke on NMC may advance our understanding of pathogenesis of chronic effects of ETS. 相似文献
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To determine the most effective treatment for acrodermatitis chronica atrophicans, several clinical trials were undertaken in recent years to evaluate whether a 2-week course of ceftriaxone would be superior to oral antibiotics. Of the 46 patients suffering from acrodermatitis chronica atrophicans, 14 were treated with ceftriaxone 2g for 15 days. The remaining patients received either oral penicillin V 1.5 million IU t.i.d. or doxycycline 100 mg b.i.d. for 20 to 30 days. Patients were followed up for at least 1 year. Of the 14 ceftriaxone-treated patients four showed incomplete regression of the inflammatory skin changes after 6 to 12 months. Two out of five patients who were monitored for Borrelia burgdorferi DNA excretion were still positive after 12 months as compared to none of six patients who were treated orally for 20-30 days. Six out of 11 patients treated orally for only 20 days needed retreatment after 6 months because of continuing skin manifestations, neuropathy or arthralgia. A 30-day duration of treatment with oral antibiotics and not the chosen antibiotic is crucial for curing acrodermatitis chronica atrophicans. The duration of treatment with ceftriaxone needed for eradication of Borrelia in acrodermatitis chronica atrophicans has yet to be determined in future studies. 相似文献
20.
In response to public concern over abuses in human medical experimentation, the dominant approach to the ethics of clinical research during the past 30 years has been regulation, particularly via institutional review board review and approval of scientific protocols and written consent forms. However, the effectiveness of regulatory mechanisms in ensuring the ethical conduct of clinical research is limited. Little attention has been devoted to the nature and role of professional integrity of physician investigators, a conscientious framework for guiding investigators in the socially important but morally complex activity of clinical research. Professional integrity is vital in forging an ethically sound relationship between investigators and patient volunteers, a relationship that differs in important ways from the patient-physician relationship in standard clinical practice. We examine critically 2 models of the moral identity of physician investigators, the investigator as clinician and the investigator as scientist; in neither of these 2 models can the physician investigator eliminate completely the moral conflicts posed by clinical research. The professional integrity of physician investigators depends on a coherent moral identity that is proper to the enterprise of clinical research. The roles of clinician and scientist must be integrated to manage conscientiously the ethical complexity, ambiguity, and tensions between the potentially competing loyalties of science and care of volunteer patients. 相似文献