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1.
The study investigated the ultrastructural characteristics of tubular gland and duct cells, as well as luminal gland cells in the isthmus region of the oviduct of laying and natural moulting hens. Tubular glands in laying birds were composed of type 1 and 2 cells. Based on the preponderance of each cell type, in relation to the location of a developing egg in the oviduct of the domestic fowl, these gland cells may represent different functional states of the same cell. The findings of the study on natural moulting birds suggest that autophagy is a process confined to the early stages of degeneration, while necrosis occurs in the terminal stages.  相似文献   
2.
Adrenalectomies for canine adrenal tumours are associated with peri-operative morbidity and mortality. Objectives of this study included assessing the prognostic value of tumour- or surgery-related variables in predicting peri-operative mortality and overall survival in dogs undergoing adrenalectomies for primary adrenal tumours as well as pre-treatment with phenoxybenzamine on survival to discharge with pheochromocytomas specifically. A multi-institutional retrospective cohort study was performed across nine institutions. Electronic medical record searches identified 302 dogs which met the inclusion criteria. Data collected included dog-related, tumour-related, treatment-related, surgery-related, and outcome variables. Univariate and multivariable logistic regression and cox proportional hazards models were used to identify variables associated with death prior to discharge and tumour-related survival. Overall, 87% of dogs survived to discharge with a tumour-related survival time of 3.96 years. Post-operative complications were reported in 25%. Increased surgical time (p = 0.002) and pre-surgical medical treatment other than phenoxybenzamine (p = 0.024) were significantly associated with increased peri-operative mortality while ureteronephrectomy (p = 0.021), post-operative pancreatitis (p = 0.025), and post-operative aspiration pneumonia (p < 0.001) were significantly associated with decreased overall survival. Phenoxybenzamine pretreatment had no effect on peri-operative mortality. Thirty-seven of 45 (82%) dogs with pheochromocytomas not pretreated survived to discharge, and 50 of 59 (85%) dogs with pheochromocytomas pretreated with phenoxybenzamine survived to discharge (p = 0.730). This study provides information on risk factors for death prior to discharge and tumour-related survival that may help guide clinical management and owner expectations. In addition, the study findings challenge the previously reported benefit of phenoxybenzamine for pretreatment of dogs undergoing adrenalectomies for pheochromocytomas.  相似文献   
3.
This study aimed to investigate the major salivary glands in the southern white-breasted hedgehog (Erinaceus concolor) histologically and histochemically. Five adult males were included in this study. The results showed that anatomically the shape of the parotid, submandibular and sublingual glands of the Erinaceus concolor was respectively almost pear, elliptical to pyramidal and oval. Histologically, the parotid gland had serous acini and secretory cells showed negative reaction to alcian blue (AB) (pH = 2.5) and negative response to aldehyde fuchsin (AF), methylene blue (MB) and PAS stains. The submandibular gland was a mixed gland of mucous and serous acini. The mucous acini were strongly positive for PAS, AB, MB and AF. However, serous acini were week for PAS and negative against AB, MB and AF stains. The sublingual gland was purely composed of mucous acini. The mucous acini of the sublingual gland were strongly positives for PAS, AB and MB methods. While their reaction to the AF staining was negative. In conclusion, the histological and histochemical observations of the major salivary glands of the southern white-breasted hedgehog (E. concolor) indicated that these glands shown similarities and some special different histochemical features as compared to other mammalian species.  相似文献   
4.
The morphological basis of resistance to the whiteflyBemisia tabaci Genn. (Aleyrodidae: Hemiptera) was studied. The plant characters examined were leaf area, thickness of leaf lamina, hair density, hair length, angle of insertion of leaf hair, and density of gossypol glands. Hair density and leaf thickness were positively correlated with the population ofB. tabaci, and a positive correlation was obtained between the adult whitefly population and gossypol glands on stem internodes. Cotton genotype USA-22 (sparsely hairy) was found to be more tolerant toB. tabaci than was genotype USA-13 (velvety hairy). The use of thinner and glabrous leaved cotton varieties is suggested to minimize the whitefly menace in cotton.  相似文献   
5.
Ninety-seven pure-bred Akitas were examined clinically and histologically for sebaceous adenitis. The diagnosis was established histologically in 23 Akitas by demonstrating an inflammatory reaction targeted against the sebaceous glands or a reduction in the number of glands. The clinical course of sebaceous adenitis in the Akita was similar to that seen in other breeds. The first skin lesions occurred mainly on the dorsal midline and ears. Compared with the Poodle, the age at first onset of the disease was more variable and the hair loss affected mainly the undercoat. The progression of sebaceous gland destruction varied between dogs and was not seen in all cases. Because bud-like sebaceous gland proliferation could be identified, it seems that regeneration of the sebaceous glands may occur. An autosomal recessive inheritance appears to be possible. Apart from a genetic background, immune-mediated factors possibly influence the onset and course of sebaceous adenitis.  相似文献   
6.
甲壳动物保幼激素的研究   总被引:1,自引:0,他引:1  
近年来,在甲壳动物大颚腺中发现了一种具有保幼激素活性的物质——法呢酸甲酯(MF),它是一昆虫保幼激素Ⅲ(JHⅢ)结构相似的一种倍半萜类化合物,对甲壳动物的生长、发育和繁殖有重要调控作用,而MF的分泌受到眼柄等因子的负调节作用。  相似文献   
7.
甲壳动物CHH家族神经激素结构和功能研究进展   总被引:4,自引:2,他引:4       下载免费PDF全文
王在照 《水产学报》2001,25(2):175-180
甲壳动物主要利用温度、光照周期等外界因子调节其生理状态 ,使它们的生殖活动处于最适条件下 ,来自外界因子的这些信息作用于甲壳动物的中枢神经系统 ,后者将其传递到神经内分泌系统和内分泌系统 ,神经内分泌系统和内分泌系统能够分泌一些促进因子和抑制因子以实施对性腺活动的调控。由于甲壳动物成体的生殖和蜕皮常常交替出现 ,因此 ,神经内分泌系统和内分泌系统的精确调控非常重要。甲壳动物高血糖激素 (CHH)家族神经激素是甲壳动物特有的多肽激素 ,它们主要由眼柄的X -器官窦腺复合体合成 ,它们包括 :甲壳动物高血糖激素 (CHH)、…  相似文献   
8.
Light microscopic studies have established the existence of salt glands on “Kallar grass”; leaf blades. The salt glands resembled the two‐cell type structure described for some halophytic genera within the Gramineae. The secreted salts crystallized and formed whiskers when the plants were grown under continuously high saline conditions. The salt secretion appears to be selective. The secretion of Na exceeded that of K and considerable quantities of Cl were also extruded, preferentially in concomitance with Na. The significance of growth hormones and Ca in regulating the salt secretion process is discussed.  相似文献   
9.
Trilostane, a 3beta-hydroxysteroid dehydrogenase inhibitor, has been used successfully over the last few years for the treatment of canine pituitary-dependent hyperadrenocorticism. In a prospective study of 19 dogs with pituitary-dependent hyperadrenocorticism, the adrenal glands were measured before and at least 6 months after initiation of trilostane therapy. Right adrenal gland length and caudal pole thickness and left adrenal gland caudal pole thickness increased significantly (p < or = 0.05); there was no significant change in left adrenal gland length. Enlargement of adrenal glands during trilostane therapy may occur as a result of suppression of the negative feedback mechanism affecting cortisol production.  相似文献   
10.
枣粘虫性行为时辰节律的研究   总被引:2,自引:0,他引:2  
李连昌  任自立 《林业科学》1991,27(2):145-148
本文利用腺体提取、瓶内收集、触角电位和田间试验等方法对枣粘虫产生和释放性信息素时辰节律进行了研究。其中瓶内收集性信息素的方法,在研究昆虫释放性信息素时辰节律方面报道很少,更重要的是,此法在我们的实验中取得了比较满意的效果。研究结果表明:(1)羽化后1—6天的提取物产生的触角电位无明显差异,说明性信息素在此期间的产生与日龄无关(2)腺体中性信息素的含量高峰在凌晨4点,而从体内往体外释放的高峰在早晨7点。(3)利用处女雌蛾不同时辰的诱蛾量的田间试验也进一步证明了枣粘虫产生和释放性信息素与交配行为在时辰节律上的同步性。  相似文献   
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