康贝尔鸭开产前、后甲状腺组织结构的变化

用光镜和电镜观察了康贝尔母鸭(产前组、开产组各15只)的甲状腺组织结构。结果:各组右侧甲状腺的重量和体积均大于左侧,开产组左、右测甲状腺的重量和体积均相应大于产前组;产前鸭甲状腺滤泡的直径,上皮细胞和核的高度分别为97±8μm,5.7±0.9μm,4.1±0.3μm,开产鸭则为87±18μm,8.3±0.7μm,4.83±0.24μm;开产鸭比产前鸭甲状腺具有一系列功能旺盛的结构象,如上皮细胞的游离面有长而多的微绒毛和明显的伪足,胞质内胶质滴、初级溶酶体、线粒体的数量较多,高尔基体发达,粗面内质网池扩张等。用氨银染色法,两组鸭均未发现滤泡旁细胞。此外,讨论了甲状隙的结构与功能的关系及甲状腺和性腺的关系。     

休产期和产蛋期太湖鹅甲状腺的组织细胞结构比较

在光镜和电镜水平对太湖鹅甲状腺休产期和产蛋期的组织和细胞结构作对比观察。鹅甲状腺组织是滤泡状结构 ,滤泡由单层上皮细胞构成。产蛋鹅甲状腺滤泡腔内富含胶质。休产期鹅甲状腺滤泡腔内胶质较少 ,空泡化程度高 ,呈现功能旺盛状态 ,上皮细胞顶端具有许多微绒毛 ,以摄取滤泡腔内的胶体 ;胞质内线粒体、胶质滴、溶酶体数量较多 ,内质网丰富 ,高尔基体发达。     

灰雁甲状腺的组织学研究

为研究灰雁与鹅的甲状腺结构的异同,采用不同方法,观察灰雁的甲状腺组织结构,在H-E染色的组织切片中,甲状腺实质由滤泡组成,滤泡由单层上皮细胞组成;在PAS反应中,甲状腺滤泡腔内的胶质深红染,显示胶质为糖类物质;在银染切片中,C细胞胞质内含有黑色的特异性嗜银颗粒,与太湖鹅、四季鹅不同。     

iNOS基因和VEGF基因在氟致甲状腺肿大鼠甲状腺组织中的表达

为探讨氟致甲状腺肿大的分子机理，选用4周龄SD大鼠饮用不同浓度的NaF水溶液，复制了氟中毒致大鼠甲状腺肿模型，光镜下观察了甲状腺的形态结构变化，并用RT-PCR技术检测了甲状腺组织中iNOS1TIRNA和VEGFmRNA的表达情况。结果，氟中毒大鼠甲状腺微血管明显扩张、增生，表现为明显的结节性甲状腺肿；与正常对照组大鼠相比，氟中毒组大鼠甲状腺组织中iNOSmRNA和VEGFmRNA的表达水平显著升高（P〈0．05）。结果表明，长期摄入过量氟导致甲状腺发生结节性肿大的机理之一是，氟可刺激甲状腺中iNOS基因和VEGF基因的过量表达，进而造成甲状腺组织内微血管增生。     

光照对“星杂579”产蛋鸡甲状腺组织结构的影响

对70日龄“星杂579”母鸡,以10lx的照度和14L:10D的光照周期补加光照,至270日龄时,摘取甲状腺制做光镜、电镜样品进行观察。结果:补加光照的实验组与自然光照的对照组鸡的开产率、产蛋量和甲状腺滤泡上皮的厚度差异非常显著(P<0.01),而体重和甲状腺腺体的重量、大小及滤泡腔内径没有显著差异(P>0.05)。实验组与对照组比较,其甲状腺滤泡上皮细胞(不论柱状或扁平上皮细胞)及滤泡腔内胶质均呈现功能活动旺盛的结构相。     

白唇鹿肾上腺,甲状腺的组织学观察

白唇鹿是我国特有的珍贵兽类,但很少研究。就目前资料看,在白唇鹿的野生生活习性和人工饲养管理方面已有报道,组织学研究仅见胃肠和雌性生殖器官。肾上腺、甲状腺作为内分泌器有在机体的内分泌调节中发挥着重要作用。为此,作者选用白唇鹿肾上腺、甲状腺为材料,对其组织结构作了观察研究,旨在为白唇鹿的研究利用提供基础资料。     

13例犬疑似甲状腺机能减退性疾病临床调查分析

正犬甲状腺机能减退症又称犬甲减。主要是由于犬自身甲状腺功能或结构出现了异常,引起机体分泌和合成甲状腺激素不足导致犬身体机能代谢效率降低的一类疾病。犬甲减是导致犬内分泌紊乱的重要疾病。临床上甲减患犬常表现出嗜睡、精神浑沌、运动机能减退、皮肤干燥无光伴有色素化、被毛脱落     

氟化物对FRTL细胞甲状腺激素代谢相关基因表达的影响

为探讨氟对FRTL细胞甲状腺球蛋白(TG),甲状腺过氧化物酶(TPO)和钠碘转运体(NIS)基因表达的影响,传代培养FRTL细胞,在对数生长期用氟化钠处理,使培养液中的氟浓度分别为20、10、5、2.5、1.25 mg/L,同时设空白对照细胞.培养72 h后收集细胞;采用半定量RT-PCR分析FRTL细胞TG、TPO、NIS mRNA和β-actin表达水平.试验结果表明,与对照细胞相比,较低浓度氟化钠处理的FRTL细胞TG基因表达量代偿性升高,随氟质量浓度增加(5.0 mg/L以上),TG表达量显著降低(P<0.05);各个浓度氟化钠处理的FRTL细胞TPO、NIS基因表达量均下降或显著下降(P<0.05).由此可知,氟化物降低了甲状腺细胞TG、TPO、NIS基因表达水平,造成甲状腺摄取和利用碘、甲状腺激素合成、贮存、分泌功能障碍,进而导致甲状腺结构和功能异常.     

恒河猴甲状腺与甲状旁腺的组织学观察

应用光镜和透射电镜技术，探讨了2～15岁恒河猴甲状腺和甲状旁腺的细微结构。结果表明，甲状腺实质由滤泡和滤泡旁细胞构成。滤泡大小不等，平均直径173μm，由单层低立方上皮细胞围成，细胞平均高度4．93μm，胞质内含较丰富的细胞器和胶质小泡等。滤泡旁细胞较少，平均直径13．20μm，位于滤泡之间或镶嵌于滤泡上皮细胞之间，胞质内含少量的分泌颗粒。甲状旁腺位于甲状腺内，其实质由暗主细胞、淡主细胞、暗嗜酸性细胞、淡嗜酸性细胞组成，并可见腺泡样结构和脂肪细胞。主细胞平均直径6．96μm，嗜酸性细胞11．69μm。     

氟化物对鸡甲状腺滤泡旁细胞结构的影响

为探讨氟对鸡甲状腺滤泡旁细胞结构的影响及氟引起甲状腺肿的机理 ,选用 2 50只 1日龄蛋鸡 ,随机分为 5组 ,每组 50只。第 1组为正常对照组 ;第 2 ,3,4,5组在日粮中添加不同水平的氟化钠 ,使日粮中氟的含量分别为 50 0 ,1 0 0 0 ,1 50 0 ,2 0 0 0mg/kg。试验期为 1 50d。测定血清中氟、钙含量 ,制作甲状腺组织切片和超薄切片 ,分别观察甲状腺滤泡旁细胞显微和超微结构的变化。结果表明 ,成功地复制出了不同程度的鸡慢性氟中毒模型 ,试验中后期 ,血清中氟与钙之间呈显著的正相关 (r=0 637,P<0 0 1 ) ;氟化物导致甲状腺滤泡旁细胞增生及损伤是氟导致甲状腺肿的机理之一。     

Pathologic changes, tissue distribution, and extent of conversion to ethylenethiourea after subacute administration of zinc ethylene-bis-dithiocarbamate (zineb) to calves with immature rumen function.

The toxicity of zinc ethylene-bis-dithiocarbamate (zineb), a widely used fungicide, was studied in four 4-week-old Friesian calves with immature rumen function. Calves were first subjected to liver biopsy, and thereafter, 3 of them were orally administered 200 mg of zineb/kg of body weight daily for 80 days, whereas the fourth calf served as control and remained untreated. Clinical, hematologic, and pathologic (including ultrastructural) findings were recorded. The distribution in body fluids and tissues of the parent compound and one of its main metabolites, ethylenethiourea (ETU), also was examined. Treated calves had unthrifty appearance and reduction in weight gain. They also had remarkable impairment of thyroid function, as reflected by reduction in serum concentrations of triiodothyronine and thyroxine and increase in weight of the thyroid gland associated with epithelial vacuolization and foci of hyperplasia. Moderate increase in liver glycogen content and impairment in maturation of germ cells were recorded consistently. Whereas zineb was widely distributed in body tissues, ETU accumulated mainly in the liver and the thyroid gland, although noticeable concentrations also were attained in muscle. Data were consistent with involvement of ETU mainly in the pathogenesis of thyroid gland lesions, and indicate that unweaned calves given zineb develop a clinicopathologic syndrome that does not differ qualitatively from that already described in adult cattle exposed to zineb.     

The avian thyroid gland.

There has been a considerable amount of research regarding the function of the avian thyroid gland, particularly in chickens. There is also more information on diseases of the avian thyroid gland, although it is usually in the form of case reports. This article covers a limited amount of material on the structure and function of the avian thyroid gland and its diseases.     

The histopathology of fatty liver and kidney syndrome in chicks.

Studies of the general histopathology of the fatty liver and kidney syndrome in chickens have shown abnormal accumulations of the lipid in a variety of organs but no degenerative or inflammatory reactions. Lipid was found in some skeletal muscles, alimentary tract, autonomic ganglia, central nervous system and pineal gland as well as in the liver, kidney and heart. Small amounts of lipid were sometimes seen in the exocrine pancreas, adrenal medulla and epithelium of the thyroid follicles. Lipid deposits in the liver were primarily associated with the hepatic structural unit. The glycogen content of the hepatic cell was reduced. The lipid-metabolising gastrocnemius muscle contained abnormal amounts of lipid but this did not apply to the carbohydrate-metabolising pectoralis major muscle. The thymus did not contain excessive lipid but was significantly smaller in affected than in control birds of similar ages. There was loss of tinctorial distinction between the cortex and medulla of the adrenal gland associated with decreased basophilia of the latter region. Many of these morphological changes can be correlated with previously reported biochemical findings and they are discussed in relation to the hyperlipaemia and hypoglycaemia which characterise the disease.     

The effects of different iodide availabilities on thyroid function during development in Japanese quail

Japanese quail (Coturnix japonica) were used to study the effects of different egg iodide (I) availabilities on thyroid function during development. Low (less than 50 micrograms 1/kg feed in the maternal diet) and high (1200 micrograms 1/kg feed) I availability were compared to control levels (800 micrograms 1/kg feed), a standard supplementation for game bird feed. We measured thyroid gland content of I, triiodothyronine (T3) and thyroxine (T4), plasma concentrations of T3 and T4, hepatic 5' monodeiodinase (5'-D) activity, and the response of the thyroid gland to thyrotrophin (TSH) stimulation. Embryos, on day 14 of the 16.5-17 day incubation period, and 1-day chicks were used for most studies but thyroid gland hormone content and plasma hormone concentrations were determined for more stages. With high I, thyroidal I content was elevated but thyroidal T4 and T3 were not different from controls. Plasma T3 and T4, the thyroid gland response to TSH stimulation, and hepatic 5'-D activity did not differ between control and high I. Reduced body weight occurred with high I. In general, thyroid gland weight was not altered, but some high I birds exhibited thyroid hypertrophy and altered thyroid gland function. With low I availability, thyroid gland contents of I and T4 were reduced but thyroidal T3 content was maintained. The thyroid gland response to TSH stimulation, plasma thyroid hormone concentrations, and the developmental patterns of plasma thyroid hormones, hepatic 5'-D activity, body weight and thyroid weight were not different between control and low I groups. Developing Japanese quail exhibit excellent ability to adjust thyroid function over a wide range of I availabilities. Regulation appears to occur at the level of thyroid hormone synthesis in the thyroid gland, which allows most aspects of thyroid dynamics to remain unchanged in the maintenance of circulating thyroid hormone concentrations.     

Computed tomographic features of the normal canine thyroid gland.

The computed tomographic (CT) features of the normal thyroid gland were compiled from images acquired in 25 client-owned dogs without thyroid gland disease. The mean pre- and postcontrast attenuation values were 107.5 and 169.0 Hounsfield Units, respectively. After injection of intravenous contrast medium (600 mg iodine/kg), the apparent thyroid gland volume (both lobes combined) increased from a mean value of 1148.0 nm3 to a mean value of 1188.9 mm3. All thyroid lobes were homogeneous on pre- and postcontrast images. In a craniocaudal direction, the gland spanned a region from the 1st to the 8th tracheal ring and the right lobe was often more cranial than the left. On transverse images the lobe shape was ovoid in 72%, and its location was dorsolateral to the trachea in 90% of dogs. Parathyroid glands could not be identified and an isthmus connecting both thyroid lobes was only seen in one dog. Considering the excellent visibility of the normal canine thyroid gland, CT can be beneficial in the differentiation of thyroidal versus nonthyroidal neck masses. CT also yields potential in the staging of thyroid carcinomas.     

Magnetic resonance imaging of the normal canine thyroid gland.

The magnetic resonance (MR) imaging features of the normal canine thyroid gland were retrospectively compiled from images acquired in 44 dogs presented for a variety of diseases unrelated to the thyroid gland. The appearance of the thyroid gland on different sequences, including pre- and postcontrast T1-weighted, T2-weighted, two-dimensional gradient echo, three-dimensional T2*-weighted gradient echo and proton density weighted images, were described in different image planes. The characteristic shape, location, and intensity of thyroid lobes compared with surrounding structures made them easily detectable in all dogs. The most common location of the thyroid lobes was dorsolateral to the trachea with the maximal cross-sectional area of the lobes located ventral to C2/3 or C3 in more than 85% of the dogs. The majority of the lobes were ovoid on transverse images. An isthmus was seen in one large dog and parathyroid glands could not be seen. The mean maximal thyroid lobe diameter on transverse images was 8.1 mm, being twice the mean diameter of the common carotid artery. Considering the excellent conspicuity and characteristic appearance of the canine thyroid gland, MR imaging can be beneficial in the diagnosis of diffuse thyroid diseases, in differentiating thyroid vs. nonthyroid neck masses and in staging and treatment planning of thyroid tumors in this species.     

Effects of rapeseed-press cake glucosinolates and iodine on the performance, the thyroid gland and the liver vitamin A status of pigs.

Rapeseed press cake (per kg DM 181 g EE, 341 g CP and 23.3 mmol glucosinolates) was tested in a long-term experiment with a total of sixty pigs (live weight range 24 to 104 kg). The 3 x 2 factorial design consisted of three rapeseed press cake levels (no rapeseed press cake--control, 75 g or 150 g rapeseed press cake per kg diet) each with two iodine dosages (125 or 250 micrograms supplementary iodine per kg diet). Reduced feed intake and depressed weight gain were found in groups receiving 150 g rapeseed press cake per kg diet, which correspond to 3.2 mmol glucosinolates per kg diet. At an inclusion level of 75 g rapeseed-press cake per kg diet no differences in feed intake and growth intensity were recorded in comparison to the rape feed free control. The rapeseed-press cake diet increased the weight of thyroid gland and liver and decreased the serum thyroxine (T4) concentration. Higher iodine dosage increased the serum T4 concentration of pigs receiving 75 g rapeseed press cake per kg diet (= 1.6 mmol glucosinolates per kg diet) to the level of the control group and retarded the enlargement of the thyroid gland. Intake of rapeseed products lowered the iodine content of the thyroid gland, however, there was no significant difference between groups given 1.6 and 3.2 mmol glucosinolates per kg diet. The vitamin A content of the whole liver and the vitamin A serum concentration were not influenced by the diets tested. However, rapeseed press cake and the glucosinolates, respectively, decreased the vitamin A concentration per gram liver due to the organ enlargement and the resulting dilution effect.     

Quantitative morphological studies on various organs of the MINI-LEWE miniature swine]

Quantitative morphological studies were conducted into 27 MINI-LEWE miniature pigs, with the view to exploring the correlations between a number of organs (liver, kidneys, heart, spleen, pancreas, adrenal gland, and thyroid gland) and parameters (live weight, age, weight at slaughter, length from snout to tail root, and internal length of slaughter body). The results are presented in 12 ilustrations and five tables.     

光照对肉鸡生长发育影响的机理研究 Ⅰ.光照对星布罗肉鸡甲状腺组织结构的影响

对星布罗肉鸡施以间歇光照,诱起明显的光周期反应。结果,实验组鸡的增重显著高于对照组(P<0.01),其甲状腺滤泡上皮细胞及滤泡腔内胶质均呈现功能活动旺盛的构相。从而说明:甲状腺在光照影响肉鸡生长发育的机制中起重要作用。实验还对星布罗肉鸡的甲状腺激素释放途径进行了探讨。