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121.
E. Edward Peeples Ann Geisler Carol J. Whitcraft Clarence P. Oliver 《Biochemical genetics》1969,3(6):563-569
Phenol oxidase activity of activated A1 and A2 (A3) electrophoretic components from 19 lozenge mutant and three lozenge double mutant strains was compared to that of wild type flies. Melanin production by the activated A components with tyrosine as substrate was compared to activity in the same acrylamide gels with dopa as substrate. Melanin production decreased, first in the A1 band and then in the A2 (A3) band, with increased morphological expression of the mutant genes. No melanin bands were obtained with either substrate in five of the more severely affected mutants. A possible correlation between phenol oxidase activity and quinone production necessary for normal development of eyes, female accessory sex organs, and claws is discussed.Supported by PHS grant AM-08331-05. 相似文献
122.
Modified Microbiological Assay for Rapid Estimation of Antibiotic Concentrations in Human Sera 总被引:5,自引:1,他引:4 下载免费PDF全文
S. Ann Stroy 《Applied microbiology》1969,18(1):31-34
Antibiotic concentrations in human sera were estimated in 5 to 6 hr by a modified microbiological assay. By using Staphylococcus aureus and Streptococcus pyogenes as the assay organisms, the seeded assay plates were preincubated for 2 to 6 hr and then were stored at 4 C until used for assay. Paper discs saturated with the specimen were placed on the preincubated assay plates with reference discs saturated with known concentrations of antibiotic. After 5 to 6 hr of incubation, zones of antibacterial activity were measured and compared with a standard curve for estimation of antibiotic concentration. Results from this rapid assay method compared favorably with those from the commonly used 24-hr assay. 相似文献
123.
In 1967 we admitted 339 cases of infantile gastroenteritis; one-third of these were dehydrated, and in this group the commonest biochemical abnormality found was hypernatraemia, sometimes with metabolic acidosis. A higher incidence of dehydration was found in the patients who had received oral glucose fluids before admission. Enteropathic Escherichia coli were isolated from the faeces of 16% of the cases. Associated infections, especially of the respiratory tract, were common. Treatment was aimed at the restoration of fluid and electrolyte balance. Usually this was achieved with oral fluids, though intravenous fluids were used in the most severely dehydrated cases. Recovery was complete in 320 cases and a further 14 cases were discharged as carriers of enteropathic E. coli. There were five deaths (1·5%) in the series; three occurred immediately after admission. 相似文献
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128.
Comparative electron microscope investigations on sections of the lens cortex of the normal, mature rat, rabbit, monkey, and the normal calf reveal similar patterns of intracellular organization. The superficial lens fiber contains a nucleus, mitochondria, endoplasmic reticulum, dense granules, Golgi complex, and a quantity of small structures of low opacity which appear as filamentous and spherical configurations. Variations in number, distribution, and spatial arrangement of cytoplasmic elements in lens fibers are described. These changes in the pattern of cytoplasmic organization are concomitant with development of fibers and their displacement towards the center of the lens. Structural details of the various zones of the lens epithelium and the lens fibers are compared. 相似文献
129.
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
130.
Primary structure of rabbit skeletal muscle glycogen synthase deduced from cDNA clones 总被引:1,自引:0,他引:1
W M Zhang M F Browner R J Fletterick A A DePaoli-Roach P J Roach 《FASEB journal》1989,3(13):2532-2536
The complete amino acid sequence of rabbit skeletal muscle glycogen synthase was deduced from cDNA clones with a composite length of 3317 bp. An mRNA of 3.6 kb was identified by Northern blot analysis of rabbit skeletal muscle RNA. The mRNA coded for a protein of 734 residues with a molecular weight of 83,480. The deduced NH2-terminal and COOH-terminal sequences corresponded to those reported for the purified protein, indicating the absence of any proteolytic processing. At the nucleotide level, the 5' untranslated and coding regions were 79 and 90% identical for rabbit and human muscle glycogen synthases, whereas the 3' untranslated regions were significantly less similar. The enzymes had 97% amino acid sequence identity. Interestingly, the NH2 and COOH termini of rabbit and human muscle glycogen synthase, the regions of phosphorylation, showed the greatest sequence variation (15 of 19 mismatches and two insertion/deletion events), which may indicate different evolutionary constraints in the regulatory and catalytic regions of the molecule. 相似文献