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981.
Modern identification of Neisseria gonorrhoeae may be either accomplished by direct detection of gonococcal antigen, i.e. without microbiological culturing, or, following culturing, by rapid culture confirmation. The direct detection of gonococcal antigen in an enzyme immuno-assay (Gonozyme) shows reduced specifity especially with mixed microbial flora, and decreased sensitivity with small numbers of organisms. Culture confirmation may be achieved by a rapid sugar degradation test (API----quadFERM+), by specific enzyme detection using chromogenic substrates (Gonochek II), or by demonstration of protein I specific for Neisseria gonorrhoeae by means of monoclonal antibodies (Mikrotrak, Phadebact monoclonal GC, Gonogen II). Detection of protein I is highly sensitive and specific in both the tests of immunofluorescence and coagglutination.  相似文献   
982.
This study examined longitudinal health and intelligence data to determine whether sensory or motor deficits account for some of the age-related intellectual changes that are commonly seen from midlife onward. Although sensory and motor functioning did not account for the age-related decrements in performance on speeded, visual perceptual tasks found for this sample in previous work, we did find that hearing deficits added error variance to performance estimates on two verbal subtests of the Wechsler scales.  相似文献   
983.
The authors report a case of massive Trichuris trichiura infection, resulting in severe anaemia and congestive cardiac failure in a 9-year-old Iban boy, who was resistant to the usual oral anthelmintic treatment, but promptly responded to mebendazole retention enema. This patient also had an associated Entamoeba histolytica infection.  相似文献   
984.
985.
This study examined selective reminding and recognition memory performance of 21 severe closed-head injured patients tested within 6 months of regaining consciousness and then again after at least 1 year. Performances on selective reminding parameters were highly correlated and patients performed significantly worse at both testings than did hospitalized controls matched for age, education, and sex. Patients improved from testing 1 to testing 2 on only four of six memory variables. Average Impairment Rating at testing 1 was a marginally better predictor of memory performance at testing 2 than was length of coma. Results are discussed in terms of (a) utility of selective reminding parameters and predictors of outcome and (b) dissociations in recovery of memory parameters.  相似文献   
986.
Amphotericin B: a novel class of antiscrapie drugs   总被引:5,自引:0,他引:5  
Amphotericin B (AmB) has been able to lengthen the incubation period of intracerebrally (ic) scrapie-injected hamsters to 45 d. This article reports a linear relationship between AmB doses and the duration of the incubation periods of ic-treated animals compared with controls, a greater effect of AmB treatment administered 2 w before or the same day of ic scrapie incubation, and the ineffectiveness of mepartricin, an AmB analogue, in prolonging the incubation period of ic scrapie-injected hamsters. The beneficial effect of AmB appears due to a delay in the replication of the scrapie agent in the brain of infected hamsters. Moreover, AmB suppresses scrapie replication in the spleen of treated animals. Three hypotheses may explain these results: (1) AmB alters a hypothetical scrapie receptor, preventing the entry of the agent into central nervous system (CNS) target cells; (2) AmB interferes with mechanisms involved in scrapie replication; (3) AmB prevents the formation and accumulation of a scrapie-specific amyloid protein responsible for the disease. Whatever the mechanism of action, AmB is the only currently available drug to modify experimental CNS scrapie infection, so AmB is proposed as a novel class of antiscrapie drugs.  相似文献   
987.
Histological sections of brain from patients showing evidence of advanced pathology of Alzheimer disease (AD) were examined for the presence of herpes simplex type-1 (HSV-1) nucleic acids by a sensitive in-situ hybridization technique. Samples from neurologically normal patients were examined in parallel. Sensitivity of the assay was verified by the detection of HSV-1 nucleic acids in neurons of trigeminal ganglia taken from cases of AD and normal controls. This indicated that the hybridization reaction was sufficiently sensitive to detect latent HSV-1 infections. Positive hybridization in the brain was only detected in a confirmed case of herpes simplex virus encephalitis. These results appear to confirm previous reports that HSV-1 infection is not directly involved in the pathology associated with AD.  相似文献   
988.
Results of clinicoimmunological observation of 75 patients are presented. The aim of the observation was to show clinical efficiency of glucocorticosteroid hormones, their influence on T-immunity and immunoregulatory subpopulations in the patients with pulmonary tuberculosis The glucocorticosteroid hormones used in combination with tuberculostatics accelerated fading of the exudative phase of tuberculous inflammation and at the early stages of the treatment increased the frequency of destructions healing in the lungs. However, 10 to 15 days after the start of their use immunodepressive action on T-lymphocytes was detected. The hormones had the most pronounced suppressive effect on lymphocyte blast cell transformation with mitogen persisting even after discontinuation of their use.  相似文献   
989.
990.
The pharmacology of dichloroacetate   总被引:18,自引:0,他引:18  
Dichloroacetate (DCA) exerts multiple effects on pathways of intermediary metabolism. It stimulates peripheral glucose utilization and inhibits gluconeogeneis, thereby reducing hyperglycemia in animals and humans with diabetes mellitus. It inhibits lipogenesis and cholesterolgenesis, thereby decreasing circulating lipid and lipoprotein levels in short-term studies in patients with acquired or hereditary disorders of lipoprotein metabolism. By stimulating the activity of pyruvate dehydrogenase, DCA facilitates oxidation of lactate and decreases morbidity in acquired and congenital forms of lactic acidosis. The drug improves cardiac output and left ventricular mechanical efficiency under conditions of myocardial ischemia or failure, probably by facilitating myocardial metabolism of carbohydrate and lactate as opposed to fat. DCA may also enhance regional lactate removal and restoration of brain function in experimental states of cerebral ischemia. DCA appears to inhibit its own metabolism, which may influence the duration of its pharmacologic actions and lead to toxicity. DCA can cause a reversible peripheral neuropathy that may be related to thiamine deficiency and may be ameliorated or prevented with thiamine supplementation. Other toxic effects of DCA may be species-specific and reflect marked interspecies variation in pharmacokinetics. Despite its potential toxicity and limited clinical experience, DCA and its derivatives may prove to be useful in probing regulatory aspects of intermediary metabolism and in the acute or chronic treatment of several metabolic disorders.  相似文献   
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