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81.
82.
Summary Canine distemper, a naturally occurring viral disease of dogs which often terminates in parainfectious demyelination, was used as a model to study the role of acid proteinase, neutral proteinase and beta-glucuronidase in demyelination. These enzymes were higher in cerebella of dogs with distemper-associated demyelination than in age-matched controls. The highest elevations corresponded with the most severely demyelinated cerebella. The source of the increased enzymes activities was apparently unrelated to the lymphocytes present in areas of demyelination.The direct effect of distemper virus and serum on these enzymes was tested in canine glial monolayers. Virus infection resulted in lower enzyme activities in cells concomitant with the appearance of cellular lesions. There was a relative increase of beta glucuronidase activity in the media suggesting that distemper virus released pre-formed lysosomal enzymes. Serum which was obtained from dogs with distemper-associated demyelination and had previously demyelinated cerebellar explants, also decreased activities of all 3 enzymesin vitro.The 3 enzymes were measured in gerbil brains at various time intervals following unilateral cerebral infarction to determine if processes other than demyelination also caused these enzymes to be increased. Uncomplicated ischemic necrosis (24 h post infarction) did not alter the activities of these enzymes. Invasion of macrophages to ingest and digest necrotic tissue 10 days after infarction resulted in greatly increased acid proteinase and beta-glucuronidase, but unchanged neutral proteinase, activities.It was concluded that the increased activities of acid proteinase and beta-glucuronidase in demyelinated tissue probably are derived from macrophages ingesting damaged tissue. Neutral proteinase may be more specifically involved in the demyelinating process since this is partially located within myelin and can degrade the basic protein of myelin.Supported in part by Research grant Nos. GM 1052 and Al-09022 from National Institutes of Health Service, U.S. Public Health Service.  相似文献   
83.
PHA对人扁桃体T细胞CD4和CD8抗原复合表达的研究   总被引:3,自引:0,他引:3  
  相似文献   
84.
Technical advancements in target archery have been extended to widespread use of "scopes" which magnify the target. In fact, these optical devices are simple converging lenses used at an arm's length from the eye. They produce a magnified image, but it is an image that suffers from significant dioptric blur, diminished somewhat by use of a peep sight in the bowstring which functions as an aperture stop. Visual acuities were taken with these scopes and, as might be expected, it was found that subjects saw no better with them. With the highest power scopes, acuity actually decreased. Experienced archers did slightly better with these aids than those with no archery experience.  相似文献   
85.
目的研究蒸汽吸人性损伤犬伤后血浆肿瘤坏死因子水平的改变及其与吸入性损伤呼吸循环功能受损程度的关系.方法取犬15条,以蒸汽致重度吸入性损伤,分别于伤前、伤后1h、2h、3h、4h观察有呼气相气道阻力(RE)、心率(HR)、心输出量(CO)、动脉血氧分压(PaO2)、血浆TNF水平;伤后4h致死动物,取肺做病理检查.结果伤后1hTNF、RE升高,HR、CO、PaO2下降;TNF与RE正相关(r=O.965,P<O.01),与CO负相关(r=-0.824,P<O.05).结论严重蒸汽吸入性损伤激发TNF分泌,这是诱发肺损伤及循环系统甚至全身器官功能障碍的重要原因.  相似文献   
86.
The availability of commercial, pre-packaged extracorporeal cardiopulmonary support (ECPS) circuits, which are simplified for rapid set-up and priming, has made the intra-hospital resuscitation of moribund patients routine. The successful utilization of this technology in the emergent setting requires planning and the coordination of personnel familiar with the technology. Many issues must be addressed when a patient requiring life-sustaining support utilizing this technology at an outlying hospital, must be transported while on ECPS. After reducing the size and weight of the ECPS cart and obtaining Federal Aviation Administration approval for use during aeromedical transport, the Emanuel Hospital Mobile Surgical Transport Team (MSTT) was able to extend the use of emergency cardiopulmonary bypass to outlying medical facilities. The patients selected for transport, using ECPS, are a group of patients with a potentially survivable pathology unlikely to survive inter-hospital transport without such measures. This report describes our experience with inter-hospital transport of patients on ECPS with special emphasis on transport considerations.  相似文献   
87.
An arachnoid cyst arising within the internal auditory canal, or within the cerebellopontine angle and subsequently extending into the internal meatus and enlarging it, is a rare occurrence. Nevertheless, the neurootologist and the neurosurgeon have an interest in its existence because its clinical manifestations are identical with the ones produced by a schwannoma, involving overwhelmingly the cochleovestibular nerve in that region. An equally rare observation in that location is the presence of ectopic neuroglial tissue. The two can occur independently or in combination. Examples of such lesions are presented, and their possible pathogenesis is discussed.  相似文献   
88.
侗族预防医学思想初探   总被引:2,自引:0,他引:2  
在实地调查搜集民族民间传统医药资料的基础上,把广泛流传于侗族民间预防疾病的方法,以及民族风情、民俗习惯中对防治疾病非常有利的内容进行综合分析归纳;对侗族预防医学思想的形成进行了初步探索,为深入系统整理侗族预防医学思想体系提供了具有一定价值的参考资料。  相似文献   
89.
采用SCL—90症状自评量表对某铁路分局467名列车乘务员的心理卫生状况进行了分析。结果显示总均分、阳性症状均分、阳性项目数、九组症候群因子分、达到或超过中等严重程度的发生频数均显著高于对照组。经多元逐步回归分析,仅细菌总数和二氧化碳对列车乘务员心理卫生状况有一定影响,其原因多与工作环境的不良因素和工作性质有关。  相似文献   
90.
There is no well-established therapy for treating infections of heart-assist or artificial heart devices, a serious problem with life-threatening consequences. We used a promising new approach in which antibiotic-impregnated polymethylmethacrylate beads were placed around an implanted left ventricular assist device to control an external blood pump infection in a bridge-to-transplant patient. In this case report, we describe the potential of antimicrobial-impregnated polymethylmethacrylate beads for in situ control of infections involving external surfaces of cardiovascular devices.  相似文献   
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