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Alkaline and acid phosphatase activities were studied in the ovary and oviducts of pullets from the age of 2-32 weeks. Adult fowls were similarly studied. Alkaline phosphatase activity was present only in the glandular grooves and crypts of the immature oviducts. Alkaline phosphatase activity appeared at the pits of epithelial evaginations as glandular formation commenced. The young, non-secreting glands also showed the enzyme activity. But in the mature oviduct, alkaline phosphatase activity was confined to only the uterovaginal glands or sperm host glands and the epithelium of the vagina. In the ovary, alkaline phosphatase activity in the theca interna increased as the diameter of the follicles increased. Acid phosphatase activity was not present in the ovary, but in the oviduct, the enzyme activity was present in the uterine (shell gland) glands and in the uterovaginal epithelium and glands (sperm host glands). Alkaline phosphatase activity in the ovarian follicles and in the immature oviduct is thought to be related to histodifferentiation of these structures. 相似文献
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B Unni P Barrera M Muszynska-Pytel G Bhaskaran KH Dahm 《Canadian Metallurgical Quarterly》1993,24(4):173-185
During the last larval stage, corpora allata (CA) of Manduca sexta are inactivated by a factor from the brain. Apparently the same factor (allatinhibin, AI) is secreted by day 4 Vth instar brains kept overnight in Grace's medium. AI is rapidly inactivated by heat or acid but withstands exposure to alkali and can be recovered after freezing and lyophilization. Exposure to pronase, chymotrypsin, carboxypeptidases-A and -Y, as well as leucine aminopeptidase eliminated AI activity completely, whereas after exposure to trypsin and protease XVII-S, some residual activity remained. Inactivation by pyroglutamate aminopeptidase is interpreted as being due to prolinase activity of this enzyme. Incubation of CA with gentamicin, an aminoglycoside antibiotic, affects neither their ability to produce JH in vitro nor their viability in implantation assays. However, AI did not inactivate CA in the presence of low concentrations of gentamicin. This effect was used to guard against false positive assay results possibly produced by allatotoxic contamination. AI was purified by chromatography on Sephadex G-25. All activity recovered emerged from the columns in intermediate fractions with an apparent M(r) of 1,000-2,000. 相似文献
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We present a case in which a patient with primary intestinal lymphangiectasia demonstrated abnormal intestinal accumulation of tracer during 99mTc-methylene diphosphonate (MDP) skeletal scintigraphy. Early intestinal leakage with gradual colonic migration and concentration was confirmed by repeat bone scan with serial acquisitions. The mechanism for the intestinal localization of 99mTc-MDP seen in this patient is not clear. Thus, intestinal lymphangiectasia can be a cause for extra-osseous localization of bone scan agents in the intestine. 相似文献