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991.
观察了卵丘细胞共培养对小鼠生发泡期部分裸露(PNO)和裸卵(NO)成熟和发育能力的影响;分别用小鼠、大鼠、猪的卵丘细胞与小鼠PNO和NO进行了共培养。检测了小鼠PNO和NO的减数分裂能力、生发泡构型、受精和胚胎发育能力。结果,PNO、NO的减数分裂能力显著(P〈0.05)低于卵丘完整复合体(COCs)的减数分裂能力。COCs中SN型卵母细胞比率显著高于PNO和NO中SN型卵母细胞比率(P〈0.05),大部分PNO和NO的卵母细胞核型为NSN型。与对照组相比,与小鼠或大鼠卵丘细胞共培养的小鼠PNO和NO的减数分裂能力没有显著提高,但是与猪卵丘细胞共培养却可以提高小鼠PNO和NO的减数分裂能力。结果表明,猪卵丘细胞能促进小鼠卵母细胞的体外成熟,但并不影响小鼠卵母细胞的受精和胚胎发育。 相似文献
992.
993.
Sapierzyński R Fabisiak M Kizerwetter-Swida M Cywińska A 《Polish journal of veterinary sciences》2007,10(2):65-70
The aim of the present study was to evaluate the effect of Candidatus Helicobacter suis (CHS) and other Helicobacter sp. different from Candidatus Helicobacter suis (non-Candidatus Helicobacter suis, non-CHS) infection on the number of endocrine G and D cells and G/D cells ratio in antral gastric mucosa in swine. Twenty nine stomachs were obtained from clinical healthy pigs about 6 months old and weighing approximately 100-120 kg after slaughter at abattoir located in central Poland. From each stomach samples of the antral gastric mucosa were taken for histopathology, and PCR examination for presence of Helicobacter genus and Candidatus Helicobacter suis. Samples for histopathology and immunohistochemistry were fixed in 10% buffered formalin. To reveal the expression of gastrin- and somatostatin-producing cells specific antibodies were used. Selected endocrine cells were counted in the midzone of pyloric glands, the results were expressed as a mean of the number of immunoreactive cells in one microscopic field, and as the ratio of gastrin to somatostatin cells (G/D). It can be concluded that some species of swine Helicobacter can alter the number of endocrine cells in gastric antral mucosa. Some of these alterations, for example increase the number of G cells, decrease of the D cells and especially increase of ratio G to D cells can be responsible for development of gastroesophageal ulcers in swine. 相似文献
994.
Krauze M Truchliński J Cendrowska-Pinkosz M 《Polish journal of veterinary sciences》2007,10(2):109-112
The present study involved 180 slaughter turkey-hens of heavy Big-6 type divided into four groups (in triplicate repetition for 15 birds). All the birds were fed with the same standard full-dose mixtures in 5-stage system. The turkey-hens of groups I, II and III were given 1,2,4-triasole derivative (3-(2-pyridil)-4-phenyl-1,2,4-triasole-5-carboxylic acid), which has antibacterial, antifungal and immunomodulating properties, in amount of 50, 75 and 100 microg per 1 dm3 of water. Group IV--control was given water without the additive. The 1,2,4-triasole derivative was given to drinking water, starting from the first day of bird's life and for the whole rearing period. The present results of biochemical analysis of blood plasma showed that addition of examined substance significantly reduced concentration of protein, glucose, triglycerides and uric acid as compared to control. It was stated that tested 1,2,4-triasole derivative elevated the level of HDL fraction percentage and alkaline phosphatase activity in blood plasma. 相似文献
995.
Apoptosis and autophagy in involuting bovine mammary gland is accompanied by up-regulation of TGF-beta1 and suppression of somatotropic pathway 总被引:1,自引:0,他引:1
Zarzyńska J Gajkowska B Wojewódzka U Dymnicki E Motyl T 《Polish journal of veterinary sciences》2007,10(1):1-9
Regulation of mammary gland remodeling during the lactation cycle in cattle still remains unclear. The present study focused on the role of TGF-beta1 and somatotropic pathways proteins in control of the switch between survival and death of bovine mammary epithelial cells (MEC). Expressions of TGF-beta1, TGF-betaRII, IGF-IRalpha, IGF-IRbeta, GH-R, IGFBP-3, -4, and -5 in mammary tissue explants in Holstein-Fresian heifers (n = 7) and cows (n = 23) in early lactation (1-100 day), late lactation (200-260 day) and drying off (280-340 day) were compared with biochemical indices of apoptosis (caspase 3, 89 kDa fragment of PARP) and autophagy (Beclin1). The results revealed that an increase in apoptosis during the dry period was accompanied by highly significant increases in TGF-beta1 and TGF-betaRII expression. Beside biochemical markers, typical morphological features of apoptosis, such as cell shrinkage, separation from the neighboring cells and condensation of chromatin were observed. TGF-beta1 expression and induction of apoptosis was facilitated by the suppression of somatotropic pathway during drying off, manifested with down-regulation of GH-R and IGF-IRalpha, and up-regulation of IGFBP-4 and -5. This is the first report describing autophagy in the bovine mammary gland. Similarly to apoptosis, the intensity of autophagy was the highest in the dry period, as shown by increased expression of Beclin1 and morphological features, e.g. autophagosomes, autophagic vacuoles. Autophagy observed in the involuting mammary tissue could be the natural cell defense against transient undernourishment and action of apoptogenic peptides (e.g. TGF-beta1, IGFBPs), thus maintaining cellular homeostasis in the dry period. 相似文献
996.
本文以安徽省黄山市为例,探讨了其区域旅游系统空间结构模式和优化的问题。在分析了前人关于区域旅游系统空间结构模式与优化理论的基础上,通过实证分析表明:黄山市旅游区目前的旅游系统空间结构处于放射模,式阶段,旅游线路体系的完善和空间结构的重组与优化,可以促使黄山市旅游区演变为较理想的扩展模式。 相似文献
997.
Histological Evaluation of Selected Organs of the Eurasian Beavers (Castor fiber) Inhabiting Poland
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I. Dolka A. Giżejewska Z. Giżejewski W. Kluciński J. Kołodziejska 《Anatomia, histologia, embryologia》2015,44(5):378-390
There is a general scarcity of data on the histological structure of major organs in the Eurasian beaver (Castor fiber). This study presents the histological characteristics of beaver organs such as the liver, spleen, cardiac muscle, lungs and kidneys. Tissue samples were collected from 21 beavers and analysed. Selected samples of tail tissue were additionally examined. Tissue samples were placed in neutral buffered formalin and embedded in paraffin. 4‐μm‐thick sections were stained with haematoxylin and eosin, and other staining techniques were also used. Scant amounts of inter‐lobular connective tissue were found in the liver. Ion or copper deposition was not observed, but scattered cytoplasmic glycogen deposits were present in hepatocytes. Our results suggest that beavers have defensive rather than storage spleens. Interestingly, the presence of melanin in splenic red pulp was noted. The histological structure of the examined organs closely resembled that of other rodent species. According to our knowledge, this is the first study evaluating the histological structure of beaver organs. Nevertheless, precise characterization of the evaluated organs requires further work with the involvement of accurate and reliable techniques, such as molecular biology or electron microscopy methods. 相似文献
998.
Marcin Zaj?c Marcin P. Szczepanik Piotr M. Wilko?ek ?ukasz R. Adamek Zbigniew J.H. Pomorski Wies?aw Sitkowski Marcin Go?yński 《Canadian journal of veterinary research》2015,79(2):136-140
Atopic dermatitis is a common allergic skin disease in dogs. The aim of this study was to examine the possibility of a correlation between biophysical skin variables: skin hydration (SH), skin pH, and erythema intensity measured in 10 different body regions and both total Canine Atopic Dermatitis Extent and Severity Index (CADESI-03) and CADESI measured in a given region (CADESI L). The study was conducted using 33 dogs with atopic dermatitis. The assessment of the biophysical variables was done in 10 body regions: the lumbar region, right axillary fossa, right inguinal region, ventral abdominal region, right lateral thorax region, internal surface of the auricle, interdigital region of right forelimb, cheek, bridge of nose, and lateral site of antebrachum. Positive correlations were found between SH and CADESI L for the following regions: the inguinal region (r = 0.73) and the interdigital region (r = 0.82), as well as between total CADESI and SH on digital region (r = 0.52). Also, positive correlations were reported for skin pH and CADESI L in the lumbar region (r = 0.57), the right lateral thorax region (r = 0.40), and the lateral antebrachum (r = 0.35). Positive correlations were found in the interdigital region between erythema intensity and the total CADESI-03 (r = 0.60) as well as the CADESI L (r = 0.7). The results obtained suggest that it may be possible to use skin hydration, pH, and erythema intensity to assess the severity of skin lesion but positive correlation was only found in < 13.3% of possible correlations and usage of these measures in dogs is limited. 相似文献
999.
1000.
M. Larska M. K. Krzysiak A. Jabłoński J. Kęsik M. Bednarski J. Rola 《Zoonoses and public health》2015,62(2):105-110
Hepatitis E is an important public health problem mostly in developing but occasionally also in industrialized countries. Domestic and wildlife animals are considered reservoirs of the hepatitis E virus (HEV). Since no information on the prevalence of autochthonous HEV infections in human and animal in Poland is available, the aim of the study was to investigate the HEV seroprevalence of different wildlife species as potential virus reservoirs in the country. No HEV antibodies were found in any of the sera collected from the red deer (Cervus elaphus), European bison (Bison bonasus), roe deer (Capreolus capreolus), elk (Alces alces), fallow deer (Dama dama), sika deer (Cervus nippon), Tatra chamois (Rupicapra rupicapra tatrica) or brown bear (Ursus arctos). HEV‐specific antibodies were detected in 44.4% (95% CI 38.3–50.7) serum samples originated only from wild boars. The percentage of seropositive wild boars differed significantly between the provinces and was positively correlated with the wild boar density and rurality of the area. This study showed that HEV circulates among wild boar population in Poland, and this species should be considered as an important reservoir of the virus. 相似文献