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41.
【目的】研究中华蟾蜍(Bufo gargarizans)蝌蚪在不同发育阶段甲状腺的组织学变化。【方法】以处于变态高峰前后5期(28,33,38,42,46期)的中华蟾蜍蝌蚪为试验材料,用Motic BA300光学显微镜对各个发育时期蝌蚪的甲状腺进行组织学观察,测定蝌蚪的全长、体质量和肝质量等形态指标,并分析这些形态指标与甲状腺直径、滤泡平均直径及最大直径的线性相关性。【结果】在28期时,中华蟾蜍蝌蚪甲状腺出现但无分泌甲状腺激素的功能;33期时,甲状腺具备了分泌甲状腺激素的能力;此后甲状腺进一步发育,在蝌蚪前肢展开期甲状腺活性达到最强;至尾完全吸收期,甲状腺机能减弱。蝌蚪全长、体质量及肝质量与甲状腺直径及滤泡直径呈正线性相关。【结论】具有分泌机能的甲状腺出现的发育时期,与两栖动物变态类型相关;分泌高峰期出现的发育时期与幼体持续时间密切相关。中华蟾蜍蝌蚪的全长可以直观地反映其甲状腺的机能活性。 相似文献
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补血草属(Limonium Mill.)植物能有效适应高盐环境,广泛分布于典型的草原群落、沙质草原和内陆盐碱地上。文章对近年来研究较多的几种白花丹科补血草属植物(中华补血草、黄花补血草、大叶补血草和二色补血草)在形态、生理特征以及分子机制等方面的耐盐性研究进展进行了综述,同时比较了补血草属植物间的耐盐性研究情况,最后对补血草属植物今后的研究方向进行了展望。 相似文献
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Olivier Taeymans Luc Duchateau Elke Schreurs Martin Kramer Sylvie Daminet Jimmy H. Saunders 《Veterinary radiology & ultrasound》2005,46(2):139-142
The repeatability of ultrasonographic measurements of the canine thyroid gland was evaluated. The variability of three different parameters (the maximal length, width, and height) within observer, between observer and between dogs was assessed based on three different measurements made by each of three observers infive healthy beagle dogs. From the three parameters, the volume of the gland was estimated using a formula of a rotation ellipse. The height and the volume had the lowest intra- and interobserver variability, while measurements of the length had the biggest intra- and interobserver variability. The mean values, with their 90% confidence interval were: height = 0.53cm [0.33-0.73], length = 2.45cm [2.04-2.85], width = 0.62cm [0.46- 0.78], volume = 0.38 cm3 [0.20-0.55]. 相似文献
45.
AIM: To study the effects of intrathymic inoculation of liver specific antigen (LSA) on hepatocyte apoptosis after liver allotransplantation. METHODS: Orthotopic liver transplantation was used in this study. Group Ⅰ: syngenic control (Wistar-to-Wistar); Group Ⅱ: acute rejection (SD-to-Wistar); Group Ⅲ: thymus inoculation of SD rat LSA day 7 before transplantation. The observation of general situation and survival time, hepatocyte apoptosis and LAT expression in liver transplants were used to analyze immune state of animals in different groups. RESULTS: The general situation of group Ⅰ was very well after transplantation. Recipients of groupⅡ lost body weight progressively and all died within day 9 to day 13 post transplantation. As for group Ⅲ, the general situation of recipients was remarkably better than that in group Ⅱ. The positive cells of apoptosis in group Ⅲ detected by TUNEL were not significantly different from that in group Ⅰ, but was significantly lower than that in group Ⅱ. LAT was detected at any time in group Ⅱ with peak expression at day 5 and day 7 post transplantation. In contrast, LAT was not detected in any other groups. CONCLUSION: Intrathymic inoculation of LSA protects hepatocytes from apoptosis after liver allotransplantation. 相似文献
46.
Exons 4 to 8 of the tumour suppressor gene p53 were analysed in 25 skin and 25 mammary tumours of 50 dogs. A 1 bp deletion (ACCAC) was detected in codon 89 in exon 4 in a squamous cell carcinoma. A missense mutation CGCCAC (argininehistidine) was present in codon 162 in exon 5 in a mammary adenocarcinoma. Moreover, a silent mutation occurred in codon 103 (serine) of exon 4 in a mammary adenoma. The somatic nature of the three mutations was demonstrated. 相似文献
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GIOVANNA BERTOLINI TOMMASO FURLANELLO DAVIDE DE LORENZI MARCO CALDIN 《Veterinary radiology & ultrasound》2006,47(5):444-448
We conducted a retrospective study in presumed normal dogs to determine the adrenal gland attenuation and volume values. Multidetector computer tomography (MDCT 16) analysis of the gland was carried out in 48 adult dogs without evidence of adrenal gland disease that underwent CT examination for acute spinal injuries. The mean nonenhanced attenuation value +/- SD of the left adrenal gland was 36.0 +/- 5.3 HU (range: 22.0-42.0 HU). The mean nonenhanced attenuation value +/- SD of the right gland was 34.3 +/- 7.0 HU (range: 20.4-48.6HU). The mean enhanced attenuation value +/- SD were: left gland 101.5 +/- 10.6HU (range: 86.8-128.0 HU), and right gland 97.4 +/- 12.4 HU (range: 58.9-123.6 HU). The mean CT volume +/- SD were: left gland was 0.60 cm3 (range: 0.20-0.95; SD 0.17), and right gland (0.55cm3, range: 0.22-1.01; SD 0.19). Attenuation values and volume data were related to age, weight, and gender, using ANOVA. There was no statistically significant difference between the left and right side or in adrenal measurements, because of body weight class effects. The animal effect was the most important source of variation for all adrenal measurements. Based on our study, CT is an effective method for assessing adrenal characteristics in the dog. Normative CT data are provided to allow estimation of normal adrenal gland size and volume. 相似文献
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Ultrasonographic images were acquired of the mammary glands of 40 bitches with physiologically lactating (n = 20) or inflamed glands (n = 20). Echogenicity, structure, homogeneity, thickness, and distinguishability of each tissue layer were assessed. Additionally, overall echogenicity was noted. In the normal lactating gland, different tissues could be differentiated easily. The parenchyma was, without exception, separated from adjacent tissues and was visible as medium echogenic tissue with a coarse-grained structure. The tissue always had some echogenic lines and anechoic areas and was slightly heterogeneous. The loss of distinct layering of the tissue was characteristic of an inflamed mammary gland and inflamed regions had reduced echogenicity. Additionally in five bitches with mastitis, the ultrasound examination was repeated five times for documentation of the progress of the illness and associated changes, supplemented with a color Doppler sonogram to assess changes in blood vessel density. Information from the examinations carried out via B-mode did not allow treatment success to be predicted. Two bitches with reduced blood vessel density centrally had a poor outcome whereas three bitches with increased blood vessel density had a good outcome. Thus, Doppler sonography might be a useful tool to obtain information of the prognosis in acute canine mastitis. 相似文献