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Bovine infertility is a major cause of loss in the livestock industry. In the present study bovine oviduct cell cultures were infected with a Chlamydophila abortus strain. A direct evaluation of infection was performed by means of May Grünwald-Giemsa and immunocytochemistry for chlamydial LPS, which revealed inclusion bodies and vacuolisation. SEM and TEM analysis of infected cells showed various degrees of cell damage and conglutination of microvilli. This finding suggests that cattle infertility may result from an alteration of oviduct environment caused by multiplication of C. abortus. This microorganism, among other infectious agents, could be considered a potential causative agent of bovine infertility.  相似文献   
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Fishes thriving in polar habitats offer many opportunities for comparative approaches to understanding protein thermal adaptations. Investigations on the remarkable evolutionary adaptations to these environments of basic proteins such as hemoglobin, the oxygen carrier, can provide new insights into the mechanisms studied in temperate organisms and can shed light on convergent processes evolved in response to thermal adaptations. At the molecular level, hemoglobins are one of the most intriguing systems for studying the relationships between environmental conditions and adaptations. This review summarizes the current knowledge on molecular structure, biological function and phylogeny of hemoglobins of fish species living in both polar habitats but having different evolutionary histories. In benthic, non-migratory, cold-adapted fishes, the stability of thermal conditions may have generated no or few variations in selective pressures on globin sequences through evolutionary time, so that sequences retain the species phylogenetic “signal”. In pelagic, migratory, cold-adapted or temperate fishes, variations in selective pressures on globin sequences caused by variations in temperature accompanying the dynamic life style may have disrupted the phylogenetic “signal” in phenetic trees.  相似文献   
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Background  

Cynara cardunculus L. is an edible plant of pharmaceutical interest, in particular with respect to the polyphenolic content of its leaves. It includes three taxa: globe artichoke, cultivated cardoon, and wild cardoon. The dominating phenolics are the di-caffeoylquinic acids (such as cynarin), which are largely restricted to Cynara species, along with their precursor, chlorogenic acid (CGA). The scope of this study is to better understand CGA synthesis in this plant.  相似文献   
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