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991.
992.
Oviduct histochemistry and site of synthesis of a 29.7 kDa jelly coat glycoprotein in the anuran Lepidobatrachus laevis 总被引:2,自引:2,他引:0
The oviduct of the anuran Lepidobatrachus laevis contains three morphological regions, each of which contains a histochemically distinct luminal mucosa. In the pars recta, the most anterior portion of the oviduct, there are periodic acid-Schiff base (PAS)-positive simple glands and epithelia. In the pars convoluta, there are alcian blue-positive, combined alcian blue- and PAS-positive and PAS-positive gland types. The most posterior region, the pars uterina, contains alcian blue-positive and alcian blue-negative epithelial cells. Previous work has shown that solubilized egg jelly contains a major 29.7 kDa glycoprotein subunit that was detected in oviduct tissue extracts from the pars convoluta in the present study. Rabbit antisera to the 29.7 kDa egg jelly glycoprotein of L. laevis reacted with the major pars convoluta glycoprotein and there were no immunoreactive components in the pars uterina. The slight immunoreactivity detected at 29.0–37.0 kDa in pars recta extracts is not believed to be the jelly molecule, based on low immunoreactivity and subunit molecular weight measurements. We conclude that the synthesis of the 29.7 kDa egg jelly glycoprotein is restricted to the pars convoluta region of the oviduct. 相似文献
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996.
V. N. Barai A. I. Zinchenko L. M. Zalashko L. A. Eroshevskaya I. A. Mikhailopulo 《Biotechnology letters》1995,17(6):599-602
Summary The title compound was prepared by a three-stage enzymatic procedure consisting of (i) RNA hydrolysis to a mixture of ribonucleosides using intact mycelium of Spicaria violacea, (ii) transribosylation of exogenous adenine employing whole cells of Escherichia coli as a biocatalyst, and (iii) conversion of formed adenosine into ATP by the enzymes of alcohol fermentation and the kinases extracted from baker's yeast. 相似文献
997.
Johan D. Vochteloo Paul J. A. Timmermans Jo M. H. Vossen John A. H. Diujghuisen 《International journal of primatology》1995,16(3):277-293
Most surrogate-reared long-tailed macaques persistently avoid a big novel object, whereas most mother-reared subjects approach
it. A striking difference between these attachment figures is that the mothers moved about with their infants, whereas the
surrogates were fixed to the wall In this experiment, we aimed to find out whether mobility of the attachment figure plays
a part in the development of an infant’s responses to big novel objects. We studied the effects of mobility of the attachment
figure by restraining mothers in their range of action. We confined mothers of the experimental group in a small part of the
home cage. Their infants could leave the cage in which their mothers were restrained. Infants that were growing up with unrestrained
mothers made up the control group. At two different ages all infants encountered a big novel object. We used two different
objects. We found that the range of action of the mother did not significantly affect the responses of infants to big novel
objects. As in the previous studies, most of the mother-reared monkeys approached the objects. The age at which an infant
was first exposed to an object did not significantly affect its behavior toward it. Further, the two different objects evoked
the same reactions. 相似文献
998.
999.
A total of 240 Salmonella strains, 158 from 730 fish samples and 82 from 276 crustacean samples, obtained during a 2 year period, were examined for resistance to 10 antibiotics. More than 90% of the strains were resistant to bacitracin, penicillin and novobiocin. The least resistance was observed to chloramphenicol (6·7%) and nalidixic acid (12%). Multiple antibiotic resistance indexing of the strains showed that more than 95% originated from high risk sources of contamination such as poultry, swine, cattle and human environments where antibiotics are often used. 相似文献
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