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DNA replication patterns in cultured female rat fibroblasts 总被引:1,自引:0,他引:1
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Experience in the anesthetic and surgical management of 25 patients with myasthenia gravis is recorded. These are subdivided into two groups: those operated on during the period 1950-1958 and those operated on during the period 1959-1964. The purpose of this paper is to indicate improvement in mortality and morbidity due to three major advances: (1) use of the decamethonium diagnostic test in a myasthenia gravis clinic; (2) improvements in assessment and management of respiratory insufficiency; and (3) avoidance of anticholinesterase treatment in the immediate and early postoperative recovery period.Fourteen patients with myasthenia gravis, including five with thymoma and two who were refractory to medication, were in the second (1959-1964) group. There were no deaths and no myasthenic or cholinergic crises. Three prophylactic tracheostomies were performed. No emergency bronchoscopies or tracheostomies were required. 相似文献
78.
Alston-Mills Brenda Li Qi Chang Ottinger Mary Ann 《In vitro cellular & developmental biology. Plant》1989,25(10):934-938
Summary Production of antibodies against peptides or poorly antigenic proteins by conventional methods often requires either large
quantities of the native immunogen or some chemical modification to increase their antigenicity. In this study an in vivo
and in vitro immunization protocol has been used to generate monoclonal antibodies against the decapeptide luteinizing hormone-releasing
hormone (LHRH). Two injections of 100 μg of avian LHRH-I into BALB/c mice were given 7 d apart. Dissociated splenocytes were
collected under sterile conditions. They were incubated with 100 μg of the immunogen in 75-cm2 tissue culture flasks in thymocyte-conditioned media. After 5 to 8 d exposure to the antigen, splenocytes were fused with
SP2/O myeloma cells by polyethylene glycol. The cells were plated into 24 wells and then incubated in hypoxanthine aminopterin
and thymidine selective media. After 14 d an initial screening was done by enzyme immunoassay. The positive wells (6/24) were
expanded into 96-well plates and rescreened. Selected lines were cloned out 3 times by limiting dilution and the most positive
expanded for ascites production. The antibody was affinity purified in a protein A column. The antibody cross-reacted with
LHRH-I and II but preferentially to LHRH-I, as shown by competitive assay. A hypothalamic extract from a mature chick showed
a higher response than preparations from whole brain explants of 1- to 3-d posthatched chicks, mature quail, and mature mouse.
This work was funded by the Maryland Agricultural Experiment Station artical no. A4975, contribution no. 8019. 相似文献
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T Iida T Momose T Tamura T Matsumoto F C Chang J Goto T Nambara 《Journal of lipid research》1989,30(8):1267-1279
The complete set of the eight theoretically possible stereoisomeric 3,6,7-trihydroxy-5 beta-cholanic acids, four of which are new, related to hyocholic and muricholic acids were prepared from chenodeoxycholic acid. The principal reactions used were 1) cis-dihydroxylation of delta 6-compounds with osmium tetroxide/N-methylmorpholine N-oxide; 2) trans-dihydroxylation of 6 alpha, 7 alpha-epoxy compounds with boron trifluoride etherate in N,N-dimethyl-formamide; 3) inversion of equatorial 3 alpha-hydroxylated compounds to the corresponding 3 beta-epimers with diethyl azodicarboxylate/triphenylphosphine/formic acid; and 4) stereoselective reduction of 7-keto derivatives with zinc borohydride (or sodium borohydride) and by metallic potassium/tert-amyl alcohol. 相似文献