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141.
Primary and metastatic malignant fibrous histiocytoma of the alimentary tract is uncommon, even though it is the most frequently diagnosed malignant soft tissue tumor in adults. In this report, we describe a case of malignant fibrous histiocytoma of the colon. 相似文献
142.
Arrhythmias induced by coronary artery ligation in cats, by CaCl2 and epinephrine in rats, and by ouabain in guinea-pigs were used as experimental models for studying the effects of a new calcium antagonist AR-1 ([1,2,5-trimethyl-4-phenyl-4-beta-(N-cyanoethyl-N-4'-methoxybenzyl) -ethylamino]piperidine, calcium channel blocker and calmodulin antagonist) on ventricular arrhythmias. Coronary ligation caused 90% lethality (ventricular fibrillation) with 12.5 min in untreated control cats, which was prevented by administration of AR-1 (4 mg/kg body weight (b.w.) before or after arrhythmia induction. Pretreatment with AR-1 afforded protection in a dose-related fashion. A dose of 1.5 mg/KG b.w. increased survival to 45%, and all cats dosed with 3 to 5 mg/Kg b.w. survived. CaCl2 (180 mg/Kg b.w., i.v.) induced ventricular fibrillation and 100% lethality. These effects were completely prevented by an anti-arrhythmic dose of AR-1 (3 mg/kg b.w.). Epinephrine-induced ventricular arrhythmias were also prevented by the same dose of AR-1. AR-1 (5 mg/kg b.w.) did not prevent ouabain (0.5 mg/kg b.w.)-induced arrhythmias that caused death within 17 +/- 3.7 min, but displayed protective effects during 67 +/- 7.7 min. The results from these animal studies, in conjunction with previously studies demonstrating coronarodilatory and anti-platelet efficacy of this compound, collectively suggest that AR-1 has a potential to become a useful antianginal and antiarrhythmic therapeutic agent. 相似文献
143.
NS Clayton 《Canadian Metallurgical Quarterly》1998,37(4-5):441-452
Comparative studies provide a unique source of evidence for the role of the hippocampus in learning and memory. Within birds and mammals, the hippocampal volume of scatter-hoarding species that cache food in many different locations is enlarged, relative to the remainder of the telencephalon, when compared with than that of species which cache food in one larder, or do not cache at all. Do food-storing species show enhanced memory function in association with the volumetric enlargement of the hippocampus? Comparative studies within the parids (titmice and chickadees) and corvids (jays, nutcrackers and magpies), two families of birds which show natural variation in food-storing behavior, suggest that there may be two kinds of memory specialization associated with scatter-hoarding. First, in terms of spatial memory, several scatter-hoarding species have a more accurate and enduring spatial memory, and a preference to rely more heavily upon spatial cues, than that of closely related species which store less food, or none at all. Second, some scatter-hoarding parids and corvids are also more resistant to memory interference. While the most critical component about a cache site may be its spatial location, there is mounting evidence that food-storing birds remember additional information about the contents and status of cache sites. What is the underlying neural mechanism by which the hippocampus learns and remembers cache sites? The current mammalian dogma is that the neural mechanisms of learning and memory are achieved primarily by variations in synaptic number and efficacy. Recent work on the concomitant development of food-storing, memory and the avian hippocampus illustrates that the avian hippocampus may swell or shrivel by as much as 30% in response to presence or absence of food-storing experience. Memory for food caches triggers a dramatic increase in the total number of number of neurons within the avian hippocampus by altering the rate at which these cells are born and die. 相似文献
144.
145.
M Brenner T Shankel NS Wang TA Waite H Wong A Hamilton Y Tadir T Milner J Boyajian E Chung B Tromberg AF Wilson MW Berns 《Canadian Metallurgical Quarterly》1996,153(3):1136-1140
Laser exposure of the pulmonary parenchyma during treatment of emphysema and other clinical indications causes acute lung injury. Animal investigations are needed to understand and control laser-induced lung injury. We hypothesized that lung injury is deeper from Nd:YAG laser exposures than CO2 exposures because of deeper penetration of Nd:YAG wavelength light. We compared the temporal evolution of histologic injury in rabbits resulting from continuous mode shallow CO2 and Nd:YAG laser pulmonary parenchymal exposures applied in rabbits. Forty-six New Zealand white (NZW) rabbits underwent treatment with CO2 laser (n=18), Nd:YAG laser (n=18), or sham thoracotomy control (n=10) to the visceral pleural surface using 1 min of exposure (5 watts, defocused to 70 W/cm2 power density for both lasers). Animals were killed at 0, 4, 7, 21, and 49 d after exposure. Lung injury, similar to that seen clinically in humans, developed in all laser-treated animals. Injury progressed from ischemia and vascular congestion, to edema and necrosis, followed by pleural and parenchymal fibrosis. The acute injury was qualitatively distinct and slightly deeper in CO2 than Nd:YAG-treated animals (p<0.02) despite the shallower depth of penetration of the CO2 laser. These findings may imply that higher absorption coefficient for CO2 laser energy results in greater focal temperatures and injury in the areas of direct exposure, and suggest that Nd:YAG laser exposure at these settings may cause shallower injury than CO2 lasers in humans undergoing clinical treatment. 相似文献
146.
JN Aaron CC Carlisle MA Carskadon TJ Meyer NS Hill RP Millman 《Canadian Metallurgical Quarterly》1996,19(9):707-710
Our laboratory previously reported continuously monitored peak sound levels in several areas at Rhode Island Hospital. The number of sound peaks greater than 80 A-weighted decibels (dBA) was found to be high in the intensive and intermediate respiratory care unit (IRCU) areas, even at night. Environmental noise of this magnitude is potentially sleep-disruptive. Therefore, we hypothesized that nocturnal peak sound levels of > or = 80 dBA would be associated with an increase in EEG arousals from sleep in patients in the IRCU. Six patients underwent sleep monitoring while environmental peak sound levels were continuously recorded. Each 8-hour period (2200 to 0600 hours) was broken down into 30-minute segments. If there were 10 minutes or more of wakefulness in a segment, that segment was dropped from further analysis. Of the remaining 61 segments, there was a very strong correlation (r = 0.57, p = 0.0001) between the number of sound peaks of > or = 80 dBA and arousals from sleep. These 61 periods were then classified as quiet, moderately loud, and very loud based on the number of sound peaks (< or = 5, 6-15, and > 15, respectively). Analysis of variance revealed a significant difference between the number of arousals (p = 0.001) in quiet periods and that in very loud periods. We conclude that environmental noise may be an important cause of sleep disruption in the IRCU. 相似文献
147.
EV Karpenko AN Shul'ga NS Shcheglova SA Eliseev RI Vil'danova-Martsishin AA Turovski? 《Canadian Metallurgical Quarterly》1996,58(5):18-24
Pseudomonas species S-27 was grown on various substrates. It was established that the Pseudomonas species S-27 strain can produce biosurfactants of ramnolipid nature decreasing the surface and interfacial tension to 29.2 and 0.05 mN/m. respectively, as well as a biopolymer stabilizing the emulsions with hydrocarbons and oils. The biosurfactant and bioemulsifier synthesis is shown to depend of the substrate nature. 相似文献
148.
MIu Shchelkanov NG Iaroslavtseva AN Iudin VF Eremin NS Pyzhova IuA Semiletov AV Abélian LP Titov EV Karamov 《Canadian Metallurgical Quarterly》1998,32(4):717-728
This article reviews the existing knowledge base concerning the biology of spinal fusion, with the understanding that the focus is weighted toward posterolateral lumbar spinal fusion because of a relative paucity of biologic information on healing of other types of fusions. The discussion focuses first on the basic science of spinal fusion healing from the standpoint of animal modeling. Next, the discussion centers on the multitude of local factors that can affect fusion healing. Finally, the numerous systemic factors known to affect fusion healing are discussed. 相似文献
149.
NS Russell A Grummels AA Hart IJ Smolders J Borger H Bartelink AC Begg 《Canadian Metallurgical Quarterly》1998,73(6):661-670
Nearly 4 million women in the United States were physically hurt by their husbands or boyfriends in 1994. The health and well-being of these women and their children, as well as the women who are overlooked in these statistics, are jeopardized by past and current experiences with abuse within intimate relationships. Strategies for nurses in women's health care settings to screen women for current or past abuse within their intimate personal relationships, guidelines for effective responses to disclosure of abuse, and supportive interventions are described. 相似文献
150.
NS Runkel U Hinz T Lehnert HJ Buhr Ch Herfarth 《Canadian Metallurgical Quarterly》1998,85(9):1260-1265
BACKGROUND: Emergency surgery for colorectal cancer has become more aggressive and radical over the past decade. This retrospective review analyses the impact on outcome. METHODS: The results of emergency surgery within 24 h of admission were compared between 1982 and 1987 (77 patients) and 1988 and 1993 (75 patients). Patient and tumour characteristics were similar in both groups. RESULTS: Right colonic obstruction or perforation was treated by primary resection and anastomosis in 11 of 12 patients before 1988 and in all 19 patients thereafter. Primary resection was also the treatment of choice for perforated cancer of the left colon and rectum before 18 of 20) and after (20 of 21) 1988. The rate of primary resection for obstructing cancer of the left colon and rectum increased from 17 of 45 to 30 of 35. One-stage resections for obstructing cancer were performed in ten of 45 and 22 of 35 patients before and after 1988 respectively. The overall mortality rate declined from 14 of 77 to three of 75 after 1988 (P< 0.01). The rate of radical lymphadenectomy rose from six of 46 patients to 42 of 69 after 1988. The 3-year survival rate increased from 50 to 74 per cent (P < 0.05). CONCLUSION: The data support further efforts towards improving the immediate and late outcome of emergency surgery in complicated colorectal cancer. 相似文献