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1.
苹果试管苗不定根起源及其发育状况的研究   总被引:4,自引:0,他引:4  
利用光学和扫描电子显微镜观察结果表明,经琼脂生根培养基诱导产生的长富—2苹果 (Malus pumila Mill.) 试管苗的不定根起源于维管形成层。这种不定根发育不良,根表面缺乏根毛,内部解剖构造为典型的初生结构。为避免因不定根吸收、运输能力差而影响试管苗移栽成活,宜采用通透性良好的基质进行瓶内或瓶外生根,可诱导出优质不定根。  相似文献   
2.
Fifty-eight healthy horses were studied during five sporting events of various intensities and durations, namely show-jumping (n=6), cross-country in a three-day event (n=30), trotting races (n=7), galloping reces (n=7) and endurance rides (n=8). Venous blood samples were collected at rest and immediately after exercise and analysed for plasma cortisol (CORT) and lactate (LA) levels. The experimental procedure was the same throughout the investigation so as to permit a reliable comparison between the five types of exercise. The type of event significantly affected both the resting (p0.05) and the postexercise (p0.01) plasma CORT. The degree of exercise-induced hypercortisolaemia was related to both the intensity and the duration of exercise for all five sporting events, but the endurance ride induced the most and show-jumping the least serious post-exercise CORT changes. LA production was much more closely related to the intensity of the exercise than was CORT. It is concluded that simultaneous measurements of plasma CORT and LA levels may be useful to discriminate between different types of exercise, adjust training programmes, and improve our comprehension of the physiology of sport horses at exercise.Abbreviations CORT cortisol - E/R exercise to rest ratio - EDTA ethylenediaminetetraacetic acid - HR heart rate - LA lactate  相似文献   
3.
本试验旨在获得中国美利奴羊成纤维细胞生长因子10(fibroblast growth factor 10,FGF10)基因的编码区(CDS)全长序列并进行生物信息学分析,随后对FGF10基因在中国美利奴羊毛囊发育过程中的表达特征进行分析,明确其在中国美利奴羊毛囊发育过程中的表达模式,为进一步研究FGF10 mRNA表达水平与中国美利奴羊毛囊生长发育的表达调控机制奠定理论基础。采用PCR扩增获得中国美利奴羊FGF10基因CDS,并克隆到zero PCR@TM-Blunt进行测序验证;利用实时荧光定量PCR技术检测FGF10在中国美利奴羊毛囊发育过程中的表达差异。结果表明,绵羊FGF10基因CDS长度为696 bp(序列上传GenBank,获得登录号:MT872422),编码231个氨基酸,与牛和山羊的氨基酸序列同源性达100%,存在1个信号肽和1个跨膜结构域,其为分泌通路信号蛋白;实时荧光定量PCR分析表明,FGF10基因在中国美利奴羊毛囊发育过程中均表达,在毛囊发育第85天表达最高,显著高于其他毛囊发育时期(P<0.05)。本研究获得中国美利奴羊FGF10基因完整的编码区序列和毛囊发育过程中的表达特征,生物信息学分析发现,FGF10基因编码区序列具有物种间的保守性,同时FGF10在绵羊毛囊不同发育阶段的皮肤组织中表达,由此表明,FGF10基因可能在绵羊毛囊的生长发育过程中发挥重要的生物学作用。  相似文献   
4.
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   
5.
毛囊是毛纤维的生长基础,决定毛纤维的性状,角蛋白是毛囊组成的重要成分之一。近年来,对毛囊生长发育和角蛋白基因的挖掘等取得了一定的进展。文章回顾了绵羊角蛋白基因的发现,已经与人类角蛋白基因相当,但在数量和分类上存在差异;笔者介绍了绵羊毛囊的形态学结构,简述了毛囊角蛋白基因的表达定位和影响毛纤维性状的角蛋白,并分析了毛囊中的蛋白质组学技术的应用对毛囊生长发育和毛纤维性状的重要作用,以期为绵羊毛囊生长发育和羊毛性状的分子选育提供新的研究思路。  相似文献   
6.
为比较2、35日龄滩羊皮肤毛囊的发育特点与血管内皮生长因子(vascular endothelial growth factor,VEGF)和血管内皮生长因子受体2(vascular endothelial growth factor receptor 2,VEGFR2)的分布特征,探究出生后滩羊被毛生长发育的变化特点,试验应用常规HE染色及改良Masson胶原纤维染色、Gomori银氨法染色、磷钨酸染色等特殊染色观察2与35日龄滩羊皮肤组织结构特点;应用免疫组织化学法结合免疫荧光染色法观察VEGF及VEGFR2在2与35日龄滩羊皮肤组织中的分布定位,并用IPP图像分析软件进行定量分析。结果显示:与2日龄滩羊皮肤组织比较,35日龄滩羊表皮与真皮间界限更加清晰,毛囊结构发育完整;毛囊密度显著降低(P<0.05);胶原纤维与弹性纤维含量增加,形成网格状分布。免疫组化及免疫荧光结果显示,VEGF及VEGFR2在滩羊皮肤表皮及毛囊外根鞘、皮脂腺上均有表达。统计表明,VEGF及VEGFR2在2日龄滩羊皮肤组织中的表达量均显著高于35日龄(P<0.05)。综合上述结果,滩羊毛囊发育过程中,胶原纤维和弹性纤维增加明显;VEGF与VEGFR2通路在毛囊角质形成中起直接调节作用。  相似文献   
7.
Infrared thermography is a non-invasive technique which allows to distinguish between pregnant and non-pregnant animals. Detecting accurate body surface temperatures can be challenging due to external factors altering thermograph measurements. This study aimed to determine the associations between the ambient temperature, the hair coat features and the temperatures of mares' abdomens. It compared pregnant and non-pregnant mares throughout 11 months. The research was carried out on 40 Konik Polski mares, which were divided into pregnant and non-pregnant groups. The temperature (Tmax, maximal; Taver, average; Tmin, minimal) of the mares' abdomen was evaluated in two regions of interest: the whole area of the lateral surface of the mares' abdomen (Px1) and the flank area of the lateral surface of mares' abdomen (Px2). During the increasing period, the slopes in the linear regression equation did not differ significantly for ambient (Tamb) and surface temperatures in both groups. In the decreasing period, the slopes did not differ significantly for Tamb and Tmax in the non-pregnant group. They also did not differ for Tamb and Taver in Px1 and Tamb and Tmin in Px1 in both pregnant and non-pregnant groups respectively. Other slopes varied significantly (p < .001). There was no evidence of parallel changes in hair coat features and measured temperatures. The flank area appears more suitable for thermal imaging in pregnant mares due to the seasonal fluctuations in hair coat lengths.  相似文献   
8.
Hair follicle neoplasms occur in many different species, including humans. In domestic animals, they are most common in dogs. Most hair follicle tumors are benign, but malignant neoplasms can also occur. To diagnose hair follicle neoplasms, a thorough knowledge of follicular anatomy is important, given that follicular tumors are classified according to the differentiation pattern seen in the corresponding part of the normal hair follicle. This review focuses on the key diagnostic features of hair follicle tumors and follicular cysts in dogs and cats.  相似文献   
9.
The changes of cortisol, red blood cells (RBC), hemoglobin (Hb), hematocrit (Hct), heart rate (HR), respiratory rate (RR) and rectal temperature (RT) were evaluated after a reining training session in eight Quarter Horses. All parameters were measured before exercise (T0), immediately after exercise (T1), 1 h after exercise (T2), 2 h after exercise (T3) and 24 h after exercise (T4). One‐way analysis of variance (ANOVA) for repeated measures, followed Bonferroni's post hoc test, showed a significant effect of the reining training session (P < 0.0001) on cortisol, RBC, Hb, Hct, HR, RR and RT. Simple linear regression analysis showed the positive correlation (P < 0.05) between cortisol changes and variations of studied parameters in T1, T3 and T4. Exercise‐induced cortisol concentrations reflect the physiological response of reining training, suggesting that the changes observed are useful to assess the performance in reining horses and their reining training adaptability.  相似文献   
10.
Separation anxiety (SA) is a serious behavioral problem in dogs. In this study, salivary cortisol was studied to determine if the owner''s odor or voice could reduce SA in dogs. Twenty-eight dogs with SA were divided into three groups: group 1 (control), group 2 (with owner''s clothes during the separation period; SP) and group 3 (a recording of the owner''s voice was played during SP). The dog''s saliva was collected after the owner and their dog were in the experimental room for 5 min (PRE). The dog was then separated from the owner for 20 min and saliva collected four times at intervals of 5 min (SP1–4). Finally, the owner was allowed back into the room to calm the dog for 5 min, after which saliva was collected (POST). Evaluation of salivary cortisol concentrations by ELISA revealed that the ratios of SP1 concentration to PRE or POST concentrations were significantly higher in group 1 than in group 2 or 3. Additionally, the concentrations of SP1–PRE and SP1–POST among groups differed significantly. These findings indicate that the owner''s odor or voice may be helpful to managing stress in dogs with SA.  相似文献   
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