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31.
Neutralization, complement fixation (CF) and indirect fluorescent antibody (FA) assays for rubella virus were compared for sensitivity in the serologic diagnosis of infection, for demonstrating antibody in the sera of infants with suspected rubella syndrome, and in the detection of antibody elicited by past infection (determination of immunity status). The combination of CF and FA tests was shown to be the most useful for serologic diagnosis of infection, largely eliminating the need for the slower and more cumbersome interference neutralization test.Neutralizing antibodies were found to appear rapidly in the course of infection, antibodies demonstrable by immunofluorescent staining appeared slightly later, and CF antibodies were rarely demonstrable in sera collected earlier than 14 days after onset of illness. Antibodies detected by all three techniques showed good correlation in infants with clinical evidence of rubella syndrome and corresponding maternal sera. The indirect FA technique compared favorably with the neutralization test for the detection of antibody elicited by past infection (determination of immunity status) and offered distinct advantages in ease of technical performance and more rapid results. In both current and past infections, FA titers tended to be higher than neutralizing antibody titers.  相似文献   
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Data are presented to show that β-propiolactone when properly applied is a very effective agent for sterilization of regenerated collagen sutures. The chemical sterilization is accomplished with little or none of the loss in strength encountered with heat sterilization. The finished sterile suture is obtained without any harmful residue that might be detrimental to the patient.  相似文献   
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Head injury in infants and young children may produce lesions that are relatively unique for this age group. The uniqueness is generally due to the structural immaturity of the skull, meninges and brain.“Derby-hat” and diastatic fractures are common in this age group. Spurious meningoceles result from tearing of the dura which is closely adherent to the skull. The syndrome of “delayed” concussion is more commonly manifested in children. Extradural and subdural hemorrhage may develop from lacerations of the major venous sinuses. A classical extradural hematoma may occur in the absence of fracture across meningeal arterial channels.The management of patients with head injury has been improved by the more frequent use of tracheotomy, hypothermic techniques and drugs of the “lytic cocktail.” Solutions of urea in 10 per cent invert sugar are administered intravenously to control cerebral edema in selected patients.  相似文献   
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Summary The results of this study indicated that antigens prepared from the three morphological phases ofCoccidioides immitis differed in their complement fixing activity with anti-Histoplasma capsulatum pooled serum. Spherule antigens were serologically less active in tests with the anti-H. capsulatum pooled serum than antigens prepared from arthrospores and from mycelium.Antigenic determinants which are common toC. immitis andH. capsulatum appeared to be located on the intact arthrospore cellular surface but not on the surface of spherule cells.Part of a dissertation submitted to the Graduate School of Duke University in partial fulfillment of requirements for the Ph. D. degree.This work was supported by contract with the Department of the Army, Fort Detrick, Frederick, Maryland.In conducting the research reported herein, the investigators adhered to Guide for Laboratory Animal Facilities and Care established by the Committee on the Guide for Laboratory Animal Facilities and Care of the Institute of Laboratory Animal Resources, NAS-NRC.  相似文献   
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Young adult rats received either unilateral or bilateral ibotenic acid infusions in their nucleus basalis, destroying most of the cholinesterase-staining neurons in that region. Cerebral cortex levels of choline acetyltransferase, somatostatin, neuropeptide Y, and monoamines were then assayed 2.5 and 10 months after bilateral lesions, or, 2.5, 10, and 14 months after unilateral lesions. Entorhinal and cerebral cortex levels of several amino acid transmitters were also measured. As expected, choline acetyltransferase activity was decreased in the frontal cortex ipsilateral to the ibotenic acid infusion in unilaterally or bilaterally lesioned animals. Parietal cortex concentrations of somatostatin and neuropeptide Y were altered by lesioning in a complicated, time-dependent manner. Thus, while unilateral lesions transiently decreased or had no effect on these neuropeptide levels, bilateral lesions elevated the level of each neuropeptide by over 100% at 10 months. Other cortical transmitter systems investigated appeared to be less affected by nucleus basalis-lesions. Unilateral lesions had no effect on prefrontal cortex norepinephrine, serotonin, or dopamine content at 14 months post-lesioning. These different neurochemical effects of unilateral and bilateral nucleus basalis lesions may be important for developing a model for the trans-synaptic effects of cortical cholinergic deafferentation.  相似文献   
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The folypolyglutamate derivatives of pea seedlings (Pisum sativumL. cv. Homesteader) were extracted in the presence of 2-mercaptoethanoland cleaved to p-aminobenzoylpolyglutamates by treatment withZn-HCl. Azo dyes were formed by reaction with naphthylethylenediamine and purified by polyacrylamide gel chromatography. p-Aminobenzoylpolyglutamateswere regenerated from these dyes by Zn treatment and then concentratedin vacuo. These derivatives were separated according to glutamylchain length by high performance liquid chromatography on WhatmanPartisil SAX columns. The folylpolyglutamates of 4 day old peacotyledons, pea leaves and isolated chloroplasts were mainlytetra- and pentaglutamates. These and folates of shorter chainlength were labelled when seeds and aerial shoots were incubatedwith p-aminobenzoate-[14C]. Labelling of the pentaglutamatewas reduced in seeds that were imbibed in the presence of 0.1mM methotrexate. Studies of cotyledon folylpolyglutamate synthetaseshowed that polyglutamate chain length was affected by incubationtime and the concentration of tetra-hydrofolate monoglutamatein the reaction system. 1Present address: Department of Biology, University of Lethbridge,Alberta, Canada T1K 3M4 2Present address: Department of Horticulture, Xiong-yue AgriculturalCollege, Xiong-yue, Liaoning Province, China (Received August 4, 1989; Accepted December 5, 1989)  相似文献   
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Shoot-tip cultures of Quince C (Cydonia oblonga Mill.) initiated on Murashige & Skoog (MS) medium containing 5 M BA and 0.6% Phytagar showed both shoot-tip necrosis and severe vitrification. Culturing explants on medium containing 1.2% Phytagar and Ca levels of 3 mM (MS medium), 18 mM and 30 mM showed a decrease in growth with increasing medium Ca levels, being especially severe at 30 mM. The Ca content of the explants increased linearly with increasing medium Ca. Culturing explants on medium containing 3 mM, 9 mM, and 18 mM Ca at 0.6, 0.9, and 1.2% agar resulted in reduction in growth, shoot-tip necrosis, and vitrification when either factor was increased. The reduction in shoot-tip necrosis could be accounted for primarily by an increase in medium Ca levels but may also be affected by a change in explant growth. Increasing Ca concentration in the medium resulted in a linear increase in explant K, Ca, Mg, and B levels and a decrease in Mn and Na. Although increasing medium Ca or agar levels reduced vitrification, it is unclear whether they were the direct cause of the reduction in vitrification or whether this response was an effect of the reduction in culture fresh weight.Approved by publication by the Director, West Virginia Agriculture anf Forestry Experimental Station as Scientific Article No. 2199  相似文献   
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