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91.
We studied the computed tomographic (CT) appearance and determined Hounsfield units (HU) for normal thyroid tissue in eight cats. Helical CT images (2 mm collimation) were acquired from cranial aspect of the second cervical vertebra (C2) through caudal aspect of the fourth cervical vertebra (C4). Data were acquired before contrast medium administration (n = 7), after delayed contrast medium enhancement (n = 8), and immediately after contrast medium enhancement after a second dose of contrast medium (n = 8). Attenuation of thyroid tissue was compared with surrounding tissues. Before contrast medium enhancement, thyroid tissue was hyperattenuating to the surrounding soft tissues. After delayed contrast medium enhancement, thyroid tissue was hyperattenuating to surrounding soft tissues and isoattenuating to contrast medium-laden blood vessels. Immediately after contrast medium enhancement, thyroid tissue was hyperattenuating to surrounding soft tissues and hypoattenuating to contrast medium-laden blood vessels. The thyroid glands were dorsolateral to the trachea, ovoid, and displayed homogenous contrast medium enhancement. Circular regions of interest were drawn on the right and left thyroid lobes. Densitometric data of thyroid tissue were as follows: precontrast medium enhancement, 123.2 HU (95% CI: 119.4-127.1 HU); delayed contrast medium enhancement, 132.1 HU (95% CI: 127.4-136.8 HU); immediate postcontrast medium enhancement, 168.5 HU (95% CI: 163-173.9 HU). Normal feline thyroid tissue is easily detected using CT without contrast medium enhancement. This information may be useful for CT evaluation of abnormal feline thyroid glands.  相似文献   
92.
93.
The objective of this work is to develop an upland cotton, Gossypium hirsutum L. [2n = 4x =52, 2(AD)h], having a reduced level of gossypol in the seeds for food and feed uses, and a high level of gossypol in the remaining organs to limit pest incidence. Using G. sturtianum Willis (2n = 2x = 26, 2C1) as donor and G. thurberi Torado (2n = 2x = 26, 2D1) or G. raimondii Ulbrich (2n = 2x = 26, 2D5) as bridge species, two trispecies hybrids G. thurberi– G. sturtianum– G. hirsutum and G. hirsutum– G. raimondii– G. sturtianum were synthesized. Both trispecies hybrids were male sterile. Recurrent backcrossing to G. hirsutum as pollinator and selfing of the second backcross (BC) progenies resulted in seeds which were rescued by in vitro culture. In total, 1208 flowers of the trispecies hybrids and their BC progenies yielded 192 seed embryos from which 62 plants were obtained. Cytogenetic analyses indicated a relatively high frequency of chromosome pairing and chiasmata. The gland levels in backcross seeds ranged from glandless seeds to normally glanded seeds. All vegetative parts of those hybrids were glanded, but a wide range of variability for gland density was observed on leaf, stem, bract and calyx. Plants derived from seeds having a reduced level of gossypol constitute very interesting germplasm to develop a cultivated glanded cotton with low-gossypol seeds. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
94.
【目的】对意蜂工蜂毒腺蜂毒和电取蜂毒蛋白质组成的特点和差异进行探究,为进一步了解蜂毒的化学组成和合理利用提供理论依据。【方法】采用凝胶电泳和非凝胶技术对直接从毒腺内获取蜂毒(毒腺蜂毒)和电取蜂毒的蛋白质组进行比较,对差异蛋白进行质谱分析、功能鉴定和生物信息学分析。【结果】在毒腺蜂毒中,一维凝胶电泳(1-DE)鉴定19种蛋白,双向凝胶电泳(2-DE)鉴定11种蛋白,非凝胶法鉴定14种蛋白,3种方法在毒腺蜂毒中共鉴定30种非冗余蛋白质,它们是蜂毒毒素成分(50%)和保护腺体细胞免受毒素损伤的抗氧化类蛋白和蛋白成熟加工相关的蛋白折叠、分子转运类等(50%)。在电取蜂毒中,1-DE鉴定12种蛋白,2-DE鉴定3种蛋白,非凝胶法鉴定7种蛋白,3种方法共鉴定14种非冗余蛋白质,它们主要是蜂毒毒素成分(93%)。其中类磷脂酶A2在2种蜂毒中首次鉴定,肽基辅氨酰顺反异构酶在毒腺蜂毒中首次发现。蜂毒明肽前蛋白原、镇静肽在毒腺蜂毒中的含量显著高于电取蜂毒。磷脂酶A-2、毒液二肽基肽酶Ⅳ前体、毒液过敏性酸性磷酸酶和肥大细胞脱粒肽在电取蜂毒中含量较高。【结论】毒腺蜂毒中蛋白种类丰富,但电取蜂毒中主要毒素成分含量不低于毒腺蜂毒。由于蜂毒中的主要药物成分在毒素中,因此,电击取毒可有效利用蜂毒的功能成分。新发现的蜂毒蛋白对进一步认识蜂毒组成成分具有一定意义,这为蜂毒合理利用提供理论依据和实践基础。  相似文献   
95.
The purpose of this study was to analyse the effects of season, age, gonad and accessory sex glands on semen characteristics of jackass and to construct multivariate regression models to predict semen quality. In autumn, spring and summer, semen characteristics of 30 sexually mature donkeys (1,014 ejaculations) were analysed to investigate the effect of seasons on semen quality, and gonad and accessory sex gland parameters of 12 jackasses were measured immediately after ejaculation by ultrasonography to investigate the effect of seasons on reproductive organ size. Semen (598 ejaculates), gonad and accessory sex gland parameters of 40 jackasses aged between 3 and 7 years were analysed in autumn to investigate the effects of age and reproductive organ size on semen quality and to construct multivariate models. To verify the accuracy of the models, semen (476 ejaculates), gonad and accessory sex gland parameters of 20 jackasses were measured from March to June. Results revealed that semen, gonad and accessory sex gland parameters were not affected by season and age. Progressive motility (PM) was positively correlated with long axis of the spermatic cord (LASC) and negatively correlated with percentages of sperm abnormality (PSA). Total sperm count (TSC) was positively correlated with testis circumferences (TC) and cross-sectional area of cauda epididymis (CSACE). TC, CSACE, LASC and PSA were included into multivariate models to predict PM, TSC and functional sperm count (FSC) in 20 jackasses (PM = 72.332 + 0.428 LASC − 0.441 PSA; TSC = −169.929 + 8.728 TC + 0.253 CSACE; FSC = −206.645 + 8.788 TC + 0.258 CSACE). The predicted and observed values corresponded well. In conclusion, the tested models can be used for predicting semen quality of donkey.  相似文献   
96.
Increased incidence of adrenal pheochromocytoma is frequently encountered in rat carcinogenicity studies. In some of the studies, the finding is judged to be due to a rat-specific mechanism of carcinogenesis caused by a disturbance of calcium homeostasis. However, direct evidence that the proliferation of chromaffin cells in the adrenal medulla is induced solely by hypercalcemia is not available. In this study, calcium gluconate was intravenously infused for 7 days to rat chromaffin cells by a tail cuff method, and cumulative labeling with bromodeoxyuridine (BrdU) was carried out to evaluate the proliferative activity. The serum calcium concentration was dose-dependently increased, and a high calcium concentration was stably sustained from day 2 to 7. In the adrenal medulla, BrdU-positive chromaffin cells increased in the calcium gluconate-treated animals, and the BrdU-labeling index increased in a dose-dependent manner. In addition, an increased BrdU-labeling index of chromaffin cells was shown to correlate with the serum calcium concentration. Our results demonstrate that hypercalcemia directly enhances the proliferative activity of chromaffin cells and that the proliferative activity is correlated with the serum calcium concentration.  相似文献   
97.
本文分析了常用水剂农药在转盘上的流动状态,根据动量定量提出了转盘壁面开设一系列的环形延程槽以改善转盘的雾化效果,设计制作了 经转盘,并利用Marlvern粒子测试系统测量了转盘雾化的雾滴直径,试验结果证明壁面开设环形延程槽能够明显减少雾滴中经,改善转盘雾化效果。  相似文献   
98.
A 5-month-old colt with a history of nonpainful left-sided facial swelling present since birth was presented for evaluation and treatment. A diagnosis of congenital parotid salivary duct atresia was made, and surgical correction was attempted but was unsuccessful. Follow-up treatments consisted of repeat intralesional injection of 10% neutral-buffered formalin. The horse developed ventral mandibular abscessation with multiple draining tracts secondary to this treatment; however, no other significant complications occurred and a cosmetic outcome was achieved.  相似文献   
99.
《Veterinary parasitology》2015,207(1-2):125-133
In cattle, infestation with Psoroptes ovis mites may cause severe dermatitis (psoroptic mange) which compromises the health and welfare of the animals and may lead to significant economic losses. To investigate yet undocumented effects of psoroptic mange mite infestations and how successful therapy promotes animal health, the present study examined alterations of the skin, lymph nodes and adrenal glands of P. ovis infested Fleckvieh (Simmental) bulls treated with either ivermectin long-acting injection (IVM LAI; IVOMEC® GOLD, Merial; 3.15% ivermectin w/v) or saline (n = 16 each). Approximately 8 weeks subsequent to experimental infestation with P. ovis, the bulls had developed mange and were administered either IVM LAI or saline once at 1 mL/50 kg body weight by subcutaneous injection. Mite counts were conducted in weekly intervals for determination of efficacy of treatment, and following humane euthanasia of the animals 8 weeks after treatment, skin samples from affected (mangy or previously mangy) and unaffected areas, prescapular lymph nodes and adrenal glands were collected for gross and pathohistological examination. In addition, four age-matching, uninfested Simmental bulls were sampled as controls for comparison.No P. ovis mites were detected on any IVM LAI-treated bull after 28 days following treatment whereas saline-treated bulls maintained infestation throughout the study. At sampling (approximately 16 weeks after experimental infestation and 8 weeks following saline or IVM LAI treatment), saline-treated bulls displayed a severe, exsudative dermatitis with significantly increased skin thickness and inflammatory cell infiltration, significantly enlarged, hyperplastic prescapular lymph nodes, as well as significantly increased adrenal gland weights and volumes as compared to P. ovis-infested, IVM LAI-treated bulls and uninfested controls. Quantitative stereological analysis revealed that the adrenal gland enlargement in P. ovis-infested, saline-treated bulls was due to a selective increase of the volume of the zona fasciculata in the adrenal cortex. Compared to uninfested controls and P. ovis-infested, IVM LAI-treated bulls, the number of epithelial cells in the zona fasciculata was significantly increased in P. ovis-infested, saline-treated bulls, while the zona fasciculata cell volumes did not differ between the three groups of cattle. While the single point determination of serum cortisol concentrations did not reveal significant differences between the three groups of cattle at tissue sampling, the hyperplastic growth of the adrenal cortex in the P. ovis-infested, saline-treated bulls provides morphologic evidence that a chronic stress reaction is one consequence of mange mite infestations that can be prevented by efficacious acaricidal treatment.  相似文献   
100.
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