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51.
T-cell infiltration was detected by immunohistochemistry in only 2 of 10 sural nerve biopsies from patients with Guillain-Barré syndrome (GBS). The number of endoneurial macrophages, identified by the monoclonal antibody MAC 387, was increased, compared with the number in 10 cases of axonal neuropathy. Macrophage-associated demyelination was identified in 7 and axonal degeneration in 8 cases. Cytomegalovirus (CMV) genome was not detected with the polymerase chain reaction.  相似文献   
52.
Early Stroke Recognition: Developing an Out-of-hospital NIH Stroke Scale   总被引:1,自引:0,他引:1  
Objective : To develop an abbreviated and practical neurologic scale that could assist emergency medical services or triage personnel in identifying patients with stroke.
Methods : A prospective, observational, cohort study was performed at university-based EDs. Participants were 74 patients treated in a thrombolytic stroke trial and 225 consecutive non-stroke patients evaluated during 4 random 12-hour shifts in the ED. Scores on the NIH Stroke Scale were obtained for all patients by physicians. Items of this scale were modified and recoded to a binomial (normal or abnormal) scale. Serial univariate analyses using χ2 were performed to rank items. Recursive partitioning was then performed to develop the decision rule for predicting the presence of stroke.
Results : Three items identified 100% of patients with stroke: facial palsy, motor arm, and dysarthria. An Abbreviated NIH Stroke Scale based on these items had a sensitivity of 100% and a specificity of 92%. A proposed Out-of-hospital NIH Stroke Scale consisting of facial palsy, motor arm, and a combination of dysarthria and best language items (abnormal speech) had a sensitivity of 100% and a specificity of 88%.
Conclusion : Using the derivation data set, a proposed Out-of-hospital NIH Stroke Scale had a high sensitivity and specificity for identifying patients with stroke when performed by physicians in this group of 299 ED patients. Prospective studies of other health care professionals using the scale in the out-of-hospital arena are needed.  相似文献   
53.
Ischaemia-reperfusion injury (IRI) is of obvious relevance in situations where there is an interruption of blood supply to the gut, as in vascular surgery, or in the construction of free intestinal grafts. It is now appreciated that IRI also underlies the gut dysfunction that occurs in early shock, sepsis, and trauma. The events that occur during IRI are complex. However, recent advances in cellular biology have started to unravel these underlying processes. The aim of this review is to provide an outline of current knowledge on the mechanisms and consequences of IRI. Initially, IRI appears to be mediated by reactive oxygen metabolites and, at a later stage, by the priming and activation of polymorphonuclear neutrophils (PMN). Ischaemia-reperfusion injury can diminish the barrier function of the gut, and can promote an increase in the leakage of molecules (intestinal permeability) or the passage of microbes across the wall of the bowel (bacterial trans-location). Ischaemia-reperfusion injury to the gut can result in the generation of molecules that may also harm distant tissues.  相似文献   
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Summary: We report a series of 8 patients with ictal déjà vu. Subdural strip electrocorticographic (ECoG) monitoring localized the ictal epileptogenic focus as follows: right (n = 6) and left (n = 2) mesiotemporal lobe. In all 8 patients, the left hemisphere was dominant for language function based on intracarotid amytal testing. In 6 right-handed patients, ictal déjà vu was associated with a right temporal lobe focus. However, in the 2 left-handed patients, the ictal focus was left temporal lobe. Although ictal déjà vu localizes the epileptic focus to temporal lobe, this experiential phenomenon appears to lateralize to the hemisphere nondominant for handedness.  相似文献   
58.
Objectives - To determine whether dexamethasone `matures' the phosphatidylcholine (PC) composition of broncheoalveolar fluid in infants at high risk of neonatal chronic lung disease (CLD), either by increasing the proportion of dipalmitoylphosphatidylcholine (DPPC), expressed as a percentage of total PC (%DPPC), or by increasing the ratio of DPPC to palmitoyloleoylphosphatidylcholine (DPPC:POPC ratio).  相似文献   
59.
Short-term and long-term carcinogenicity of methyl carbamate (MCB) was evaluated in F344 rats and B6C3F1 mice. In experiments lasting 6, 12, and 18 months, MCB was given in water by gavage to groups of 10 male and 10 female rats at 0 or 400 mg/kg body weight, 5 days per week, and to similar groups of mice at 0 or 1,000 mg/kg. At 6 months, MCB induced atypical mitoses, cytologic alterations, cytomegaly, pigmentation, necrosis, and neoplastic nodules of the liver in rats. At 12 and 18 months, carcinomas of the liver were induced by MCB in 80-90% of male rats and in 60-80% of female rats. None was observed in control rats or in mice. In the 2-year studies, MCB was given to groups of 50 male and 50 female rats at 0, 100, or 200 mg/kg and to similar groups of mice at 0, 500, or 1,000 mg/kg, 5 days/week. Chronic focal inflammation, cytologic alteration, hyperplasia, and neoplastic nodules and carcinomas (200 mg/kg groups only) of the liver were induced by MCB in rats. Liver tumor incidence data for combined experiments in rats were: males--5% in controls, 0% in 100 mg/kg group, 14% in 200 mg/kg group, and 77% in 400 mg/kg group; females--5% in controls, 0% in controls, 0% in 100 mg/kg group, 12% in 200 mg/kg group, and 63% in 400 mg/kg group. MCB was not shown to be carcinogenic in mice.  相似文献   
60.
Salmonella arizonae are rarely isolated in the UK. Since 1966 there have been sixty-six isolates from humans of whom 35% gave a recent history of foreign travel. Terrapins and snakes are potential sources of infection.  相似文献   
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