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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.
Animal-assisted interventions (AAIs) have been associated with positive effects on human psychological and physiological health. Although the perception of quality standards in AAIs is high, only few investigations have focused on potential welfare implications for therapy dogs linked to their performance in AAIs. The standardized program “multiprofessional animal-assisted intervention (MTI)” has been carried out in adult mental health care, significantly improving patients' prosocial behaviors. In the present study, we monitored salivary cortisol and behavioral measures in therapy dogs that participated in MTI group therapy sessions in an in-patient substance abuse treatment facility. Work-related activity (lay, sit, stand, walk, and run), behavior (lip licking, yawning, paw lifting, body shake, tail wagging, and panting), response to human action (taking food treats and obeying commands), and salivary cortisol levels were analyzed over the course of 5 subsequent MTI working sessions in experienced therapy dogs (N = 5), aged 5.4 ± 2.8 years (mean ± standard deviation). Salivary cortisol levels decreased from presession to postsession in sessions 1, 2, and 3. However, only in session 4 and 5, postsession cortisol levels were significantly lower than presession levels (P = 0.043). There was no difference between salivary cortisol levels sampled on a nonworking day at home and work-related levels sampled at the therapy site. None of the behavioral parameters varied significantly over the course of the 5 MTI sessions. Both lip licking (P = 0.038) and body shake (P = 0.021) were positively correlated with the decline in cortisol during session 5. The study results suggest that trained dogs are not being stressed by repeated participation in in-patient substance abuse therapy sessions. Further investigation into the effects of animal-assisted therapy on dogs' physiological markers and behavior is warranted.  相似文献   
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4.
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   
5.
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   
6.
知识产权是企业核心竞争力的重要来源,特别是中小企业发展壮大的有效手段,因此中小企业亟须提升知识产权创造、运用、保护和管理能力.实施中小企业对接知识产权模式的有效途径是:企业进一步提高对知识产权的认识与自主创新能力,加快知识产权人才培养;同时政府要在知识产权交易、服务、运用和产权保护等方面发挥主导作用.  相似文献   
7.
异恶草酮对三叶浮萍的毒性研究   总被引:5,自引:0,他引:5  
以三叶浮萍为对象,研究了异恶草酮对其生长及体内色素的影响作用。结果表明:异恶草酮对浮萍生长抑制的24 hIC50为8.86 mg/L4、8 h IC50为5.21 mg/L7、2 h IC50为1.92 mg/L、96 h IC50为1.66 mg/L,对浮萍体内叶色素的影响作用呈良好的浓度(剂量)-效应关系,随着处理浓度的增大,浮萍体内的叶绿素和胡萝卜素含量明显减少,且叶绿素a/b值也随处理浓度的增大而减小。  相似文献   
8.
总结、分析了2019年及近年我国农药登记的基本情况和特点。最近7年来,每年微毒/低毒农药登记数量与当年农药登记总量的比值,及与本年度新增登记数量的比值均持续上升,其比值的年均值分别为82.0%和93.4%;环境友好的剂型在迅速增加,悬浮剂与本年度新增产品登记数量的比值一直处于领先位置,可分散油悬浮剂的比值增长突显,乳油比值在逐年递减;杀虫剂、杀菌剂和除草剂3大类农药登记数量与本年度新增登记数量的比值趋向显著平均;低风险的新农药登记数量在不断增加,生物源农药登记数量增长稳定,5年来其有效成分和产品的年均增长率分别为9.88%和9.46%。从政策和技术上促进特色小宗作物用药登记产品数量快速增加。上述特点表明,我国农药正朝着有利于人畜健康和生态环境安全的方向发展。  相似文献   
9.
为探明根系对色素腺体密度和棉酚含量的影响,以离体条件下的无根幼苗、不同生根状态幼苗以及无菌种子苗作为研究对象,对其茎叶色素腺体密度、棉酚含量以及棉酚生物合成关键基因表达量进行分析。结果表明,不同生根状态幼苗中,色素腺体密度和棉酚含量与一定范围内生根数呈显著正相关,随后趋于平稳。荧光定量PCR显示,棉酚生物合成关键基因GhCDN1GhWRKY1表达量在生根数多的无菌苗中显著增高,而对棉酚合成具有反馈调节作用的 GhCYP706B1表达量呈现相反趋势;无根幼苗茎叶腺体密度和棉酚含量均显著低于有根幼苗,棉酚生物合成关键基因GhCDN1GhWRKY1 GhCYP706B1表达量反而高于有根幼苗。有根幼苗中根的棉酚含量显著高于茎和叶,无菌种子苗根系中棉酚生物合成关键基因表达量显著高于茎和叶。说明棉花根系能对棉酚含量产生直接影响,同时影响腺体密度。本研究进一步验证了根系是棉酚主要合成部位,地上部分也存在少量的棉酚合成,只是不能引起棉酚发生显著变化。  相似文献   
10.
体重和温度对草鱼摄食小浮萍的影响   总被引:1,自引:0,他引:1  
研究草鱼(Ctenopharyngodon idella)对浮萍的摄食能力及主要影响因素,为合理利用草鱼控制小江回水区浮萍暴发提供依据。草鱼(体重29.7~491.2 g)取自红安县中海农业科技有限公司渔场,小浮萍种源采自重庆市云阳县高阳镇黄莲坝库湾。在试验室条件下研究了草鱼对小浮萍的最大摄食量、最大摄食率与体重和温度的关系。结果表明,在水温(25.82±0.57)℃条件下,随着体重的增加(40.36~478.17 g),草鱼的最大摄食量增大,但最大摄食率呈减小的趋势,两者与体重的相关关系分别为C_(max)=2.460W~(0.779),FR_(max)=246.0W~(-0.221);水温(16.55~30.50℃)对草鱼的最大摄食量和最大摄食率的影响极显著(P0.01),最大摄食量和最大摄食率与水温的回归方程分别为C_(max)=0.074T~(2.045),FR_(max)=0.164T~(1.940);建立的预测不同温度和体重条件下草鱼对小浮萍最大摄食率的模型为:FR_(max)=0.410T~(1.940)W~(-0.221)。  相似文献   
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