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991.
992.
High concentrations of retinoids occur in some commercial cat food formulations as a result of the use of animal liver as an ingredient. Our objective was to study the teratogenic potential of dietary vitamin A in cats. We investigated the incidence of birth defects in kittens of queens given diets with retinyl acetate concentrations of 6000, 306000, or 606000 retinol equivalents (RE)/kg diet (control, 306K, or 606K groups, respectively) for approximately 3 years [1 RE=1 micro g retinol=3.3 International Units (IU)]. Each group comprised 12-15 age-matched, nulliparous domestic short-haired queens that were exposed to toms. There were a total of 396 kittens born in 97 litters. Pregnancy rate, number of kittens per gestation and gestations per year were not significantly different among treatment groups. A total of 2, 5 and 11 malformed kittens occurred in the control, 306K and 606K groups, respectively. Malformations included cleft palate, cranioschisis, foreshortened mandible, stenotic colon, enlarged heart and agenesis of the spinal cord and small intestine, which are typical foetal defects consistent with ingestion of excess retinoids in other species. This study demonstrated that a concentration of 306000 RE/kg diet has a potential for causing birth defects in the kittens.  相似文献   
993.
It is shown that the cell bodies of the afferent fibres supplying the proprioceptivity to the extrinsic eye muscles are located within the semilunar ganglion. Furthermore, some Gasserian cells have central processes which enter the midbrain through the oculomotor nerve. Sensory ganglion cells, derived from the same strand of placodal cells forming the ophthalmic lobe, can be constantly detected within the oculomotor nerve of ox, monkey and man.
Kurzfassung Unsere Forschungen haben ergeben, dass sich die Zellkörper der fibrae afferentes, die dem äusserlichen Augenmuskeln die propriozeptive Sensibilität geben, im Ganglion des Gasser befinden. Ausserdem haben einige Zellen des Gasserschenganglion zentrale Verzweigungen die durch den Nervus oculomotorius in den Hirnstamm führen. Sensitive Ganglionzellen, die von der gleichen Reihe plakodischer Zellen stammen, und den lobus oftalmicus Gasseri formen, sind regelmassig im nervus oculomotorius des Rindes, des Affen und des Menschen zu finden.

Resume Nos recherches ont démontré que, chez le Mouton et le Porc, le ganglion de Gasser contient les corps cellulaires des fibres nerveuses desservant les fuseaux neuromusculaires des muscles extrinsèques de l'oeil. En outre, quelques cellules du ganglion de Gasser ont leurs prolongements centraux qui se portent au tronc cérébral en suivant à rebours les radicules du nerf oculomoteur. En fin, on a trouvé constamment des cellules ganglionnaires sensitives dans l'oculomoteur du Boeuf, du Singe et de l'Homme; ces cellules proviennent du même cordon de cellules placodiales qui forme le lobe ophthalmique du ganglion semilunaire.

Riassunto Le nostre ricerche hanno dimostrato che i corpi cellulari delle fibre nervose afferenti, che danno la sensibilità propriocettica al muscolo oculare estrinseco, si trovano nel ganglione di Gasser. Inoltre, alcune cellule del ganglione di Gasser hanno diramazioni centrali che portano al tronco cerebrale attraverso il nervo oculomotore. Infine, si sono costantemente incontrati nel nervo oculomotore del bovino, della scimmia e dell'uomo, cellule sensitive che provengono dallo stessotronco di cellule placodali che formano il lobo oftalmico.
  相似文献   
994.
The effect of vitamin E and/or selenium deficiency on the kinetics of erythrocyte production and destruction has been investigated in swine. The plasma iron turnover rate, 59Fe incorporation into newly formed red cells as well as the 51Cr apparent red cell half-life, were not found to be significantly affected by either vitamin E deficiency, selenium deficiency or deficiency of both, as compared to replete animals. The results of this study suggest that vitamin E is not a limiting factor for normal erythropoiesis in young growing pigs. Erythropoiesis appeared, however, to be slightly decreased in selenium deficient pigs and will need to be further investigated.  相似文献   
995.
马立克氏病病毒致瘤基因meq功能研究的概述   总被引:4,自引:0,他引:4  
马立克氏病病毒 (Marek’sDiseaseVirus,MDV)之众多已得到鉴定的基因中 ,目前有 3个基因即 132 bpr、pp38、meq被认为可能与致瘤相关。其中 ,meq与 132 bpr两个基因是MDV 1所特有 ,已证实 132 bpr的拷贝数与毒株的致弱程度有关 ,pp38则被证实可抑制机体的免疫应答。meq基因由于具有与致瘤基因jun/ fos家族类似的分子结构 ,因此 ,我们有理由认为meq基因在MDV致病、致瘤中可能发挥重要的作用。本课题在国家自然科学基金和广西自然科学基金的资助下 ,历经 5年由三个单位共同攻关…  相似文献   
996.
Two previously identified single-nucleotide polymorphism markers located within the micromolar calcium-activated neutral protease gene (CAPN1) were evaluated for their association with variation in meat tenderness using one commercial sample of Simmental x Angus crossbred calves and one multibreed, crossbred research herd. The commercial sample included 362 animals sired by 23 registered Simmental bulls bred to unregistered Angus cows and represented current industry animals in which to test the predictive merit of the markers. The second sample was a research herd including 564 steers from the Germplasm Evaluation Cycle VII population at the U.S. Meat Animal Research Center, produced with semen from popular sires of the seven Bos taurus beef breeds with the most registrations in the United States (Angus, Charolais, Gelbvieh, Hereford, Limousin, Red Angus, and Simmental) on Angus, Hereford, and MARC III cows. These animals form a relatively outbred population that constituted a stringent test of the predictive merit of the genetic markers, although small groups were half-sibs. Warner-Bratzler shear force measurements were used to determine tenderness phenotypes for all animals. The populations were genotyped for two markers that predict variation at amino acid positions 316 and 530 of the mu-calpain polypeptide, produced by the CAPN1 gene. Minor allele frequencies for markers 316 and 530 in the commercial sample were 0.17 and 0.37, respectively, and in the Cycle VII animals, were 0.20 and 0.28, respectively. Both markers showed association with shear force in the commercial sample (P = 0.04) and the Cycle VII population (P = 0.02), supporting the hypothesis that they represent potential markers to aid selection for improved meat tenderness in commercial populations of beef cattle in the United States.  相似文献   
997.
The performance was compared of cows sired by Holstein, Jersey or Brown Swiss bulls out of Holstein-Friesian×Gir dams of 1/2 to 3/4 Holstein-Friesian content. The animals were kept in a single herd under the same management. The data were analysed by least-squares techniques under a model that included the fixed effects of breed of sire, Bos taurus fraction of the dam, parity, year and season of calving, and a random cow effect. Based on 480 observations, the milk yields per lactation for the Holstein, Jersey and Brown Swiss sired groups were 2821±163, 2320±61 and 2418±119 kg, respectively. The corresponding means for fat yield per lactation were 96.9±6.6, 86.8±2.5 and 92.8±4.8 kg; for protein yield per lactation were 85.3±5.1, 71.3±1.9 and 76.3±3.7 kg; for lactation length, 339±18, 283±7 and 313±14 days for fat percentage, 3.37±0.10, 3.73±0.04 and 3.77±0.07%; and for protein percentage, 3.02±0.05, 3.10±0.02 and 3.16±0.04%. The respective calving intervals were 487±24, 408±11 and 461±245 days. The yields of milk and protein per day of calving interval were similar in the Jersey and Holstein sired groups, while the former had higher yields of fat, implying that production economics might favour the smaller Jersey crosses in production systems in which the males were not reared. Crossing with Brown Swiss did not improve performance over the Holstein sired crosses.  相似文献   
998.
Two dogs were emaciated and hypoalbuminemic due to protein-losing enteropathy associated with a severe, focal, mucoid, cryptal ectasia of the duodenum and marked villus atrophy. In one case, diseased portions of the duodenum were obvious endoscopically and were limited to discrete, focal areas in the small intestine, with apparently more undiseased tissue than diseased tissue being present. The signs and lesions in one dog resolved after initiating combination dietary and pharmacological therapy.  相似文献   
999.
1000.
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