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1.
本研究通过纵、横和水平切片,对50头成年中国水牛(Bubalus bubalis)垂体进行了组织结构观察。染色方法有四种:H-E;PAS(Periodic Acid Schiff);桔黄G和PAS-桔黄G染色法。 远侧部发达,可明显地分为三个区:PAS阳性的嗜碱性细胞较集中于多血管的喙侧部,形成嗜碱性细胞区;染上桔黄G的嗜酸性细胞在尾侧部形成嗜酸性细胞区;两者之间为嗜碱性细胞和嗜酸性细胞混合区。细胞排列成团索状和滤泡状,毛细血管和血窦丰富。结节部完全包绕漏斗茎,血管非常丰富;细胞包括胞核深染胞质较少的未分化细胞、嫌色细胞及少量PAS阳性嗜碱性细胞,它们排成小管状或滤泡状;未见有嗜酸性细胞。中间部较发达,大部或全部包绕着神经部,其组织结构呈分叶状,细胞有嗜碱性细胞和嫌色细胞两种,排列成团索状和滤泡状,但小叶的周边有一层排列整齐的嗜碱性柱状细胞;未发现Wulzeu氏圆锥。神经部较小,正中隆起主要在前侧加厚。强PAS阳性的胶体见于成年中国水牛腺垂体各部及神经垂体。 本文还对中国水牛垂体各部分的形态结构、细胞分布和胶体出现情况等方面与牛及其他动物进行了比较。  相似文献   
2.
In humans, the empty sella is defined as herniation of the subarachnoidal space into the sella turcica with invisible (total empty sella) or reduced (partial empty sella) hypophyseal size. An empty sella can be associated with endocrine disturbances. The purpose of this study was to determine if the empty sella exists in dogs or cats and whether it is associated with endocrinopathy or hydrocephalus. Archived magnetic resonance images of the head of 370 dogs and 77 cats were re-evaluated specifically for the presence or absence of the pituitary gland. Hypophyseal tissue filling more than 50% of the sella was considered normal, between 30% and 50% was defined as partial empty sella and less than 30% was defined as total empty sella. In patients with an empty sella, and in all other imaged dogs of the affected breeds, the ventricle to brain ratio was measured. In patients with an empty sella, the medical record was searched for evidence of endocrinopathy. No cat had an empty sella but 11 dogs (3%) had a small or missing hypophysis. Seven of these dogs had a ventricle to brain ratio greater than 15%. Only small dogs (mean weight of 6.7 kg) were affected. One dog with an empty sella had signs of central hyperadrenocorticism while the other 10 had no sign of endocrinopathy. We conclude that the empty sella exists in dogs but is not generally associated with endocrinopathy.  相似文献   
3.
摩杂一代水牛与广西沼泽型水牛垂体组织结构的比较研究   总被引:1,自引:0,他引:1  
对广西摩杂一代水牛的脑垂体进行组织学研究,并和广西沼泽型水牛(Bubalus bubalis)的脑垂体进行比较。将两种水牛的脑垂体做成切片,采用HE染色并通过图像分析仪进行分析。结果显示摩杂一代水牛脑垂体呈长卵圆形,其神经部细胞大小和细胞密度和广西沼泽型水牛差异不显著,中间部的嫌色细胞较广西沼泽型水牛的多,而远侧部的各种细胞出现率表现出差异显著,其中嗜酸性细胞与广西沼泽型水牛差异极显著。这些结果为培育广西奶水牛提供形态学依据。  相似文献   
4.
The aim of this retrospective reference interval observational study was to determine the mensuration of the pituitary gland (hypophysis cerebri) by analyzing CT studies in rabbits without clinical evidence of pituitary disease or central neurologic signs. Though diseases of the rabbit pituitary gland are uncommon, the pituitary gland is essential in regulation of the rabbit's endocrine system, as in other species. Currently, there are minimal published studies that detail the rabbit head anatomy on cross‐sectional imaging, and even less specifically examining the pituitary gland. The pituitary gland was measured by one observer at a single time point from transverse and reconstructed sagittal CT images in a soft‐tissue algorithm in 62 rabbits for a total of 66 rabbit head CT studies. The rabbits ranged from 0.84 to 14 years in age (mean ± SD: 5.46 ± 3.05 years) and 0.92 to 4.95 kg in weight (2.21 ± 0.83 kg). Linear pituitary measurements were performed using electronic calipers. The mean ± SD pituitary height was 4.22 ± 0.57 mm, width was 4.48 ± 0.71 mm, and length was 6.02 ± 0.70 mm. The pituitary gland height‐to‐brain area ratio was 1.10 ± 0.16 mm?1, which is much higher than the values reported in normal dogs and cats. The age, weight, and sex of the rabbits were not found to have a significant impact on pituitary gland mensuration. These measurements could be useful as a reference range for future rabbit head CT studies and to rule out pituitary enlargement or disease when evaluating rabbit pituitary glands.  相似文献   
5.
鸡胚漏斗的原基最早发生于前脑底壁,后移行于间脑底壁,漏斗的管壁最后分化成垂体的神经部。拉克氏囊的原基最早发生于原口顶壁呈直管状,后分化成分支管泡状及滤泡状,滤泡壁由嗜酸及嗜碱性细胞组成,滤泡间有嫌色细胞及窦状隙形成垂体的远侧部。部分嫌色细胞转移到漏斗基部形成垂体的结节部。最后部分嫌色细胞团又移行组成垂体的中间部。鸡胚脑上腺的原基最早发生于间脑背面,由短管状分化成管泡状及滤泡状,滤泡壁由复层柱状纤毛上皮组成。最后被膜伸入实质分成许多小叶,每小叶有1~2个滤泡腔,直至出壳结构类似。  相似文献   
6.
7.
The effects of dietary fumonisin B1 (FB1) on regional brain and hypophyseal activities of AChE (EC 3117), the enzyme which catalyses the hydrolysis of acetylcholine, were studied using 24 male Large White weanling pigs divided into four groups. Each group received one of the four diets containing 0.2, 5.0, 10.0 and 15.0 mg FB1/kg in a 6‐month feeding trial. All animals were slaughtered at the end of the feeding trial; the brains and the hypophyses obtained were carefully dissected out. Significant (p < 0.05) influence of dietary FB1 on regional brain and hypophyseal AChE activities were observed. The AChE activities in the pons, amygdala, hypothalamus and the medulla oblongata declined significantly (p < 0.05) with increased dietary FB1 concentrations. The findings of this study suggest that diets containing 5.0 mg FB1/kg and above significantly (p < 0.05) altered regional brain and hypophyseal AChE activities in the animals. Dietary exposure to FB1 at a concentration of approximately 5.0 mg/kg or more for a 6‐month period is a potential health risk that may induce adverse physiological response resulting from altered brain neurochemistry in growing pigs.  相似文献   
8.
The hypophysis of early larval stages, from the moment of hatching on the 18th day after fertilization to the 101st day of larval life, of the arctic lamprey Lampetra japonica was studied with scanning and transmission electron microscopes. A solid cord of cells of the distal part of the nasopharyngeal duct represents the early adenohypophysis. On the 20th day after fertilization, several of the epithelial cells of this structure showed first indications of secretory activity with an extensive Golgi apparatus and small electron-dense secretory granules. On the 26th day, non-secretory, stellate (=supporting) cells and secretary cells can be distinguished. Already on the 39th day, two different parts can be distinguished in the adenohypophysis: the pars distalis with cells containing small dense granules, and the pars intermedia with cells containing larger granules of medium density. The number of granulated cells increases steadily; on the 101st day two pars distalis cell types can be distinguished. The neurohypophysis consists of a thin anterior and a thick posterior part. Already on the 20th day single nerve terminals in the ependymal layer of the diencephalic (=infundibular) floor contain dense elementary granules. The number of granule-containing terminals increases steadily; on the 101st day almost all terminals contain granules. The present observations suggest an early secretory function of the lamprey hypophysis.  相似文献   
9.
鱼类下丘脑—垂体神经分泌系统功能综述   总被引:2,自引:0,他引:2  
李远友 《水产学报》1990,14(3):260-266
鱼类的生殖是受环境影响的。感觉器官把外界环境的刺激(如温度、光照等)传送到脑,使下丘脑分泌促性腺激素释放激素(GnRH),激发脑垂体分泌促性腺激素作用于性腺并促使性腺分泌性甾类激素,以促使性腺发育成熟及排出精子和卵子。  相似文献   
10.
Ontogenetic development of α-MSH-IR (alpha-melanocyte-stimulating hormone-like immunoreactivity) in the brain and hypophysis of a scyliorhinid dogfish (Scyliorhinus torazame) was studied immunohistochemically. α-MSH-IR first appeared in the hypothalamus of the brain in embryos at the 43-mm stage. Thereafter, α-MSH-positive cells and fibers gradually increased in number in mainly the tuberculum posterius of the hypothalamus during the embyonic periods. In the post-hatching juveniles at the 95-mm and 125-mm stages, α-MSH-positive structures in the brain were comparable to those in adult fish, although the distributional range of α-MSH-IR structures in the brain was less extensive than those in adult fish. In the hypophysis, α-MSH-positive cells first appeared in the caudal part of the adenohypophysis at the 54-mm stage, approximately coincident with the onset of pigmentation in the skin. During ontogenesis, the MSH-producing cells increased in number straightforwardly in the adenohypophysis. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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