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51.
The distribution of postganglionic autonomic nerve fibers in the lacrimal gland and gland of the third eyelid of dogs was studied by use of histochemical techniques. Adrenergic nerve distribution was identified by use of the sucrose-potassium phosphate-glyoxylic acid technique. A loose network of adrenergic nerves was found throughout the interstitium around acini and blood vessels and in vessel walls. Acetylcholinesterase staining was used to identify cholinergic nerve fibers. A cholinergic distribution pattern was found, although the cholinergic innervation appeared more dense than the adrenergic. In the gland of the third eyelid, mucus-secreting lobules and lipid-secreting lobules appeared to be equally innervated by parasympathetic fibers. These lobules could not be differentiated when the sucrose-potassium phosphate-glyoxylic acid technique was used. The techniques used in this study could not demonstrate whether direct contact was made by either cholinergic or adrenergic nerve fibers with secretory or myoepithelial cells. The presence of both nerve fiber types around acini suggests an interrelationship between the sympathetic and parasympathetic nervous system in lacrimal gland secretion in dogs. 相似文献
52.
Detection of Toxoplasma gondii in the milk of experimentally infected lactating cats. 总被引:1,自引:0,他引:1
Tachyzoites of Toxoplasma gondii have been found in the milk of sheep, goats, cows and mice and infection by ingestion of raw goat milk has been documented in humans. Lactational transmission from infected cats to their kittens is suspected but the organism has not been detected in the milk. The purpose of this study was to demonstrate the presence of T. gondii in the milk of experimentally infected cats. Pregnant specific pathogen free cats were inoculated orally with T. gondii at various times prior to parturition. Feces were examined for oocyst shedding after sugar solution centrifugation. Milk was collected for polymerase chain reaction (PCR) and bioassay in mice. T. gondii was detected in the milk of five of six cats by either bioassay or PCR. 相似文献
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The appearance and development of buds on leaf cuttings of Begonia × hiemalis in long and short days
Bud initiation in leaf cuttings of Rieger begonia ‘Schwabenland Red’ was not affected by daylength. Approximately 30 buds per cutting were observed 13 weeks after insertion. Of these, an average of 8.2 developed into fully grown shoots in long days as opposed to 1.9 in short days. Competition between buds was apparent in both treatments, its effect being greatest on buds with fewer than 4 leaf primordia. 相似文献
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Co-culture of ovine ova with oviductal cells in medium 199 总被引:7,自引:0,他引:7
Three experiments were conducted to test the suitability of medium 199 supplemented with 10% fetal calf serum (M199FCS) as a medium for co-culture of one-cell sheep ova with sheep oviductal cells. In Exp. 1, ova were co-cultured for 5 d in 5 ml of M199FCS or in Ham's F10 medium supplemented with 10% fetal calf serum (F10FCS). Co-culture did not increase the number of cleavages at the end of 5 d of culture, but M199FCS supported more cleavages than did F10FCS (P = .016). In Exp. 2, ova were cultured for 1 to 3 d in M199FCS alone or on oviductal, uterine or kidney cell monolayers from ewes 2 d postestrus and transferred to recipients from which they were recovered at 8 d postestrus. Co-culture with oviductal cells improved (P less than .001) the cleavage index of recovered embryos compared with culture in medium alone or co-culture with other cell types. In Exp. 3, monolayers of oviductal cells from ewes 2 d postestrus and from luteal-phase ewes were cultured as in Exp. 2. No difference was observed between the two sources of oviductal cells for their ability to support in vitro development of one-cell sheep eggs for 1 or 2 d. These studies suggest that M199FCS may be a good medium to use in an oviductal cell co-culture system for one-cell sheep ova. Results further suggest that specific secretions of oviductal cells may be important for early embryo development in vivo. 相似文献