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41.
The management of diabetes mellitus mandates measurement of blood glucose. Saliva offers an alternative to blood sampling, but measurement of the salivary glucose concentration is difficult, and the blood-to-saliva glucose time lag is uncertain. We aimed to determine the serum–saliva glucose time lag in the saliva of healthy dogs. The combined duct of the mandibular and sublingual salivary glands of 6 dogs was cannulated to collect saliva and prevent glucose degradation by oral bacteria. Following a 0.25 g/kg IV bolus of dextrose, paired serum–saliva samples were collected at baseline and in twelve 5-min blocks over 60 min. Serum and salivary glucose levels were analyzed with a linear mixed model for repeated measures with a compound symmetry error structure. Mean (±SD) saliva production was 10.3 ± 2.9 µL/kg/min, and the area under the curve (AUCglucose)saliva/serum ratio was 0.006, which highlights the magnitude of the large difference in glucose concentration between the 2 compartments. The serum–saliva glucose time lag was 30–40 min.  相似文献   
42.
为了解莱姆病螺旋体在蜱体内的发育生物学,采用直接免疫荧光试验、银染色法组织学及电子显微镜观察螺旋体,结果显示,感染莱姆病螺旋体的饥饿蓖子硬蜱雌虫未吸血与吸血0.5和1天唾腺中无螺旋体。在吸血开始后2天出现唾腺的轻度感染,3天出现唾腺的中度感染,4天和5天出现重度感染。这些结果表明,莱姆病螺旋体媒介蜱唾腺的感染程度随吸血时间的延长而迅速增高,并可在缓慢吸血期的中后期形成重度感染。莱姆病螺旋体在吸血期媒介唾腺内的大量存在,特别是重度感染的发现,为该病原螺旋体由蟀向脊椎动物宿主传播的唾液分泌途径假设提供了有力证据。本研究对莱姆病螺旋体在吸血蟀唾腺内分裂增殖的可能性进行了讨论。  相似文献   
43.
Three normal, sexually mature young boars of Swedish Yorkshire breed were treated with daily intramuscular injections of diethylstilboestrol and/or oestradiolbenzoate for a total period of 13–15 weeks. Whole ejaculates were collected on a dummy sow with an artificial vagina twice a week. The ejaculate was examined as regards semen volume, sperm concentration, sperm motility and sperm morphology. The seminal plasma was analysed for Na, K, Cl, Mg, inorganic phosphate, total protein and fructose. Testicles, epididymides and the accessory sex glands were obtained at slaughter. Material from epididymal segments A, B, Db, Fa and Fb was collected and examined for sperm morphology. Spermatocrit, osmotic pressure and plasma concentrations of Na, K, Gl, total protein and GPC were assessed in material from epididymal segment Fa. The sex glands and the accessory sex glands were examined maeroscopically and microscopically.The semen volume, the sperm concentration and consequently the total sperm count per ejaculate showed a gradual increase during the course of the investigation. This is to be expected as the boars used were comparatively young at the beginning of the experiment. These values were all within normal limits for adolescent boars.Taking all the characteristics examined into consideration no conclusive evidence was found that an exogenic administration of oestrogens to intact boars has any influence on the function of the epididymis and the accessory sex glands.  相似文献   
44.
Abstract: A male African pygmy hedgehog ( Atelerix albiventris ), estimated to be 3 years old, presented with exophthalmos and fixed abduction of the right eye. Radiographic examination revealed a retrobulbar tumor in the right orbital cavity. The mass was surgically resected but recurred 3 months later and the hedgehog died. There was no gross or microscopic evidence of salivary or lacrimal gland involvement of the tumor at surgery or at necropsy. The histopathologic, immunohistochemical, and ultrastructural findings were those of acinic cell carcinoma, the origin of which was unknown. This is the first known case of acinic cell carcinoma in an African hedgehog.  相似文献   
45.
Objective To describe a unique orbital neoplasm in dogs, of lacrimal or salivary gland origin. Animals studied Fifteen dogs with lesions consistent with a diagnosis of lobular adenomas involving the orbit were identified from the Comparative Ophthalmic Pathology Laboratory of Wisconsin from 1994 to 2001. Results The neoplasm occurred in nine females and six males. Affected dogs ranged in age from 7 to 17 years (mean = 9.7 years). Follow‐up information was available for 13 of the 15 cases. The clinical presentation included swollen/hyperemic eyelids (4/15), third eyelid protrusion (3/15), conjunctival mass (6/15), exophthalmos (4/15), resistance to retropulsion (2/15), or strabismus (1/15). In 13 cases the masses were composed of nodular, friable tissue and they were solid in two cases. Histologically, the tissue was found in encapsulated lobules resembling well differentiated lacrimal or salivary glands but completely lacking ducts. Granular PAS‐positive material was found within the cytoplasm. There was recurrence in 10 of the 13 cases available for follow‐up. Of those cases in which enucleation or exenteration was performed (3/15), there was recurrence of disease in one case. In three cases the dogs were euthanized before recurrence at 3 months, 5 months and 3 years post surgery. None of the deaths was related to the tumor. Conclusion In the 15 cases reviewed, lobular adenomas of the orbit presented clinically and histologically as a benign neoplasm of lacrimal or salivary gland origin. Recurrence was likely unless the mass was completely excised, at times requiring orbital exenteration.  相似文献   
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48.
陆地棉色素腺体的表达及其遗传的特殊性   总被引:2,自引:1,他引:2  
陆地棉种子及各部器官含有有毒物质棉酚,这种情况与棉株各部器官着生有色素腺体的状况有关联。研究结果表明:色素腺体在棉株各器官上的分布极具特殊性,有色素腺体棉与无色素腺体棉杂交后代,不同个体的不同器官上的色素腺体的分布具有多样性;色素腺体密度的不均匀性;色素腺体表达时期的不一致性;以及各种色素腺体类型模式出现频率的不规律性。色素腺体的遗传亦极具特殊性,难于用两对基因质量性状遗传或微效多基因数量性状遗传理论进行圆满解释。本研究倾向于维尔逊和斯密斯提出的“基因对不同器官上色素腺体的表达具有可变的表现度作用”的观点。根据本研究结果,对育种及良繁工作如何提高无色素腺体类型或高色素腺体类型的中选率提出了可减少误判的依据。  相似文献   
49.
This report describes two cases of unilateral traumatic injury to the parotid salivary gland or duct and the subsequent development of severe ipsilateral peripheral dental caries. Ultrasonographic examination of the parotid salivary gland and duct was indicative of parotid glandular atrophy in one case and demonstrated parotid duct obstruction in the second case. To the authors’ knowledge, the effects of the loss of function of the parotid salivary gland on the horse's dentition has not been documented and should be considered as a potential side effect of surgical ablation of the parotid salivary gland.  相似文献   
50.
It is unknown how ungulate physiological responses to environmental perturbation influence overall population demographics. Moreover, neonatal physiological responses remain poorly studied despite the importance of neonatal survival to population growth. Glucocorticoid (GC) hormones potentially facilitate critical physiological and behavioral responses to environmental perturbations. However, elevated GC concentrations over time may compromise body condition and indirectly reduce survival. We evaluated baseline salivary cortisol (CORT; a primary GC in mammals) concentrations in 19 wild neonatal white-tailed deer (Odocoileus virginianus) in a northern (NS) and southern (SS) area in Pennsylvania. After ranking survival models consisting of variables hypothesized to influence neonate survival (i.e. weight, sex), the probability of neonate survival was best explained by CORT concentrations, where elevated CORT concentrations were associated with reduced survival probability to 12 weeks of age. Cortisol concentrations were greater in the SS where predation rates and predator densities were lower. As the first evaluation of baseline CORT concentrations in an ungulate neonate to our knowledge, this is also the first study to demonstrate CORT concentrations are negatively associated with ungulate survival at any life stage. Glucocorticoid hormones could provide a framework in which to better understand susceptibility to mortality in neonatal white-tailed deer.  相似文献   
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