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71.
Hybridization of deoxyribonucleic acid (DNA) from Lactobacillus bulgaricus (ATCC 11842) with DNA of L. lactis (ATCC 12315), L. helveticus (ATCC 15009), and L. jugurt (ATCC 521) showed 86.0% reassociation with L. lactis, 4.8% with L. helveticus, and none with L. jugurt. 相似文献
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The free-living hermaphroditic nematode, Caenorhabditis briggsae, enters a dauer stage under certain conditions in axenic culture. Dauer larvae differ from directly-developing third-stage larvae in internal structure, size at time of second molt, morphology of second and third cuticles, separation zone of cuticular caps, and survival at 4 C and 37 C, temperatures fatal to other stages. Males, which occur rarely in liquid medium, may mature under conditions which cause most of the hermaphrodites to go into the dauer stage, resulting in a culture with increased male-to-hermaphrodite ratio. 相似文献
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The submicrosomal distribution of hepatic uridine diphosphate glucuronyltransferases in the rabbit 总被引:6,自引:3,他引:3
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1. Rabbit liver microsomes were subfractionated into rough- and smooth-surfaced types, and glucuronyltransferase activity in each microsomal subfraction was determined with p-nitrophenol, o-aminophenol and phenolphthalein as substrates. The glucuronyltransferase activity measured with p-nitrophenol and o-aminophenol as substrates was localized predominantly in rough-surfaced microsomes. Glucuronyltransferase measured with phenolphthalein as substrate was equally present in rough- and smooth-surfaced microsomes. 2. Phenobarbital pretreatment of rabbits did not stimulate any of the glucuronyltransferase activities measured in either rough- or smooth-surfaced microsomes. 3. Preincubation of rabbit liver microsomes for 30-60min. at 37 degrees under oxygen did not cause any loss of glucuronyltransferase activity. Such preincubation caused either no change or increased enzyme activity in both submicrosomal fractions. The relative distribution of transferase activity in rough- and smooth-surfaced microsomes was not affected by preincubation. 相似文献
76.
B Mondovì G Rotilio M T Costa A Finazzi-Agrò E Chiancone R E Hansen H Beinert 《The Journal of biological chemistry》1967,242(6):1160-1167
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K Imakawa T R Hansen P V Malathy R V Anthony H G Polites K R Marotti R M Roberts 《Molecular endocrinology (Baltimore, Md.)》1989,3(1):127-139
Bovine trophoblast protein-1 (bTP-1) is a secreted glycoprotein that consists of several forms differing slightly in mol wt and isoelectric point. It is produced by bovine conceptuses after about day 15 of pregnancy and is believed to play a key role in signalling the presence of an embryo to the mother. In this study, a series of recombinant cDNA clones corresponding to the mRNA for bTP-1 have been isolated from cDNA libraries representing day 18-19 bovine conceptus poly(A)+ mRNA. Base sequencing of several cDNAs indicated that multiple mRNAs for bTP-1 exist. Northern blotting and primer extension experiments showed that the mRNAs average about 1 kilobase in length. One apparently full-length cDNA clone consisted of 1035 bases up to the beginning of the poly(A) tail. It contained an open reading frame of 195 codons which began at a position 79 bases from the 5' end. Its entire sequence was 85% identical to that of a cDNA for the immunologically related ovine trophoblast protein-1 (oTP-1) and about 79% identical to that for a bovine interferon-alpha II (IFN alpha II). The highest conservation of sequence (greater than 90%) was noted in the 3'-untranslated sequences of the bTP-1 and oTP-1 cDNAs. The deduced amino acid sequence of bTP-1 shared 80% identity with oTP-1, between 45-55% with human, rodent, porcine, and bovine IFNs of the alpha 1 subfamily and about 70% with a bovine IFN alpha II. A single potential site for N-glycosylation was noted at Asn78. These results show that bTP-1, like its ovine counterpart oTP-1, is structurally related to the IFN alpha S. We suggest that these embryonic IFNs play a role in controlling immunoreactions at the trophoblast-uterus interface as well as triggering other maternal responses to pregnancy. 相似文献
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In a cross sectional survey of risk factors for coronary heart disease three questions about mental distress were included in a questionnaire completed by 13,704 people, 64% of the total population aged 20-54 in one municipality. Overall, 860 (12.5%) of the men and 1141 (16.8%) of the women reported having at least one symptom of mental distress. There were no distinct differences between the age groups. Single people, separated and divorced people, and those who reported that the financial situation of the family during their childhood was difficult reported more mental problems. Heavy smoking, frequent alcohol consumption, and, in men, little or no physical activity in leisure time were also associated with a high prevalence of mental distress. By multiple regression analyses, marital state, financial situation of family during childhood, and current lifestyle were found to be highly significantly associated with mental distress. Including a few questions on mental distress in health surveys provides a way to establish relations between such symptoms and social conditions and lifestyle in large numbers of subjects. 相似文献