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141.
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安徽省鸡免疫抑制性疾病的流行病学调查 总被引:8,自引:0,他引:8
采集了安徽省6个主要养鸡地区65群鸡的185只病鸡共986份组织样品,对可引起免疫抑制性疾病的5种最常见病毒进行了PCR检测。结果,传染性腔上囊病病毒(IBDV)、鸡传染性贫血病毒(CIAV)、马立克氏病病毒(MDV)、禽白血病病毒(ALV)和网状内皮增生症病毒(REV)的群阳性率和个体阳性率分别为73.08%和40.91%、46.15%和25.95%、41.54%和17.84%、18.46%和7.57%、13.85%和4.86%,其中被检鸡之二重或多重混合感染的总阳性率为24.33%。调查结果证实,免疫抑制性疾病在安徽省的商业鸡群中普遍存在,并与鸡群疾病多而复杂、损失大相关。 相似文献
143.
Comparison of morphology, viability, and function between blood and milk neutrophils from peak lactating goats
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Sui Zhi Tian Chai Ju Chang Chih Chi Chiang Huo Cheng Peh Mu Chiou Huang Jai-Wei Lee Xin Zhao 《Canadian journal of veterinary research》2005,69(1):39-45
The morphological features of blood and milk neutrophils from peak lactating goats were compared using light microscopy, scanning electron microscopy and flow cytometry in order to investigate the cytological changes of neutrophils after migration into the mammary gland. The kinetics of reactive oxygen intermediates (ROI) generation and gelatinase release of blood and milk neutrophils, with or without stimulation of phorbol 12-myristate, 13-acetate ester (PMA), were used to characterize their responses to inflammatory stimuli. Neutrophils isolated from goat milk were highly segmented and contained multi-lobed nuclei. Ultrastructurally, milk neutrophils were more ruffled on the surface compared to blood neutrophils. Approximately 30% of milk neutrophils were undergoing cell death, either necrosis or apoptosis, in contrast to 8% of blood neutrophils. The ROI production of activated milk neutrophils peaked earlier than blood neutrophils, but the duration and the intensity were much less. Neutrophils from both sources augmented the release of gelatinase in response to PMA (1 ng/mL). However, the amount of gelatinase released from milk neutrophils was lower (P < 0.05) than that of blood neutrophils. In summary, more neutrophils become apoptotic and necrotic in the mammary gland, presumably due to spontaneous aging, the process of diapedesis, and the interaction with milk components. Milk neutrophils have impaired functionalities in comparison with blood neutrophils. The information is relevant when studying mammary gland immunity and related diseases, such as mastitis. 相似文献
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V. Villar B. Colao I. Calles‐Venal J. G. Fernndez‐lvarez M. Fernndez‐Caso J. M. Villar 《Anatomia, histologia, embryologia》2005,34(Z1):54-54
Chondrocytes dedifferentiate to a fibroblast‐like phenotype on plastic surfaces. Dedifferentiation is reversible if these cells are then cultured embedded in gels as alginate, agarose or collagen. Chondrocytes cultured in suspension on a non‐adherent surface are also known to form aggregates of differentiated cells. The knowledge of chondrocyte behavior in culture is relevant for tissue engineering purposes. In this report we describe a simple method to culture differentiated or redifferentiated rabbit auricular chondrocytes on plastic surfaces with a stable phenotype. When chondrocyte aggregates formed in suspension are next seeded on plastic surfaces, most of them attach to the plastic as round or polygonal cells, and this morphological differentiation, confirmed by the presence of type II collagen, is stable for long culture periods. We also report that the addition of aggregates to monolayer cultures of dedifferentiated chondrocytes results in their redifferentiation, as is shown by their morphological changes and the synthesis of type II collagen. Therefore, this simple method can be useful for the study of chondrocyte behavior on plastic surfaces and for redifferentiating previously proliferated chondrocytes in tissue engineering techniques. Furthermore, these results demonstrate that, in addition to culture conditions such as cell isolation method or cell‐density, chondrocyte behavior on plastic depends on the presence or absence of aggregates resulting from the dissociation process. 相似文献
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不同地下水位植物蒸腾耗水特性研究 总被引:20,自引:6,他引:20
在甘肃省民勤治沙站利用非称量测渗仪研究了梭梭、柠条等 10种沙区植物的蒸腾耗水特征。结果表明 ,各种植物 5a的总蒸腾量由大到小排列为 :沙枣、花棒、沙木蓼、柠条、梭梭、白皮沙拐枣 ;随植物年龄增长 ,蒸腾系数有上升的趋势 ,而蒸散系数有下降的趋势 ;在民勤沙区 6~ 9月是主要蒸腾季节 ,该时段的蒸腾量占全年蒸腾量的80 %~ 90 % ;植物的蒸腾量随年龄的增长而迅速增加 ,但增长幅度随物种不同而异。一般生长快的植物增长快 ,生长慢的植物增长慢。 相似文献
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Minimal Set of Metabolic Pathways Suggested from the Genome of Onion Yellows Phytoplasma 总被引:1,自引:0,他引:1