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为了解家兔(Oryctolagus curiculus)黄艾美耳球虫(Eimeria flavescens)的内生发育史,用不同接种剂量感染20只无球虫兔,采用常规石蜡切片技术进行研究。共观察到4代裂殖生殖和1代配子生殖。每一代裂殖生殖阶段都含有2种类型的裂殖体:粗型和细型。第1代裂殖生殖发生于感染后60~72h,主要位于空肠的腺上皮;第2代裂殖生殖发生于感染后84h,位于盲肠和结肠的腺上皮;第3代裂殖生殖发生于感染后96~120h,位于盲肠和结肠的绒毛上皮;第4代裂殖生殖发生于感染后144~153h,位于结肠和盲肠的腺上皮。感染后167h,开始配子生殖阶段,成熟卵囊出现于感染后215h。本研究中对于裂殖生殖代数划分与文献报道不同,并观察到2种形态的裂殖体。  相似文献   
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Domestic cats exhibit physiological proteinuria due to the excretion of cauxin, a carboxylesterase, into the urine. In the present report, we demonstrate that cauxin is excreted in a species-, sex-, and age-dependent manner. Although the cauxin gene is conserved in mammals, including human, mouse, and dog, urinary cauxin was found only in member of the genus Felis and lynx (bobcat, and lynx) and not in other Felidae (genus: Panthera and puma) tested. In mature cats, cauxin excretion was higher in intact males than in castrated males or in intact or spayed females. Daily cauxin excretion decreased immediately after castration. Immunohistochemistry confirmed that cauxin expression in the kidney proximal straight tubules was higher in intact males than in castrated males. Urinary cauxin was detectable by Western blotting in cats older than about 3 months, and its excretion increased with age. In a zymographic esterase assay, urine contained a major cauxin band; by contrast, kidney homogenates contained three major bands, comprising two carboxylesterases and an unidentified esterase, and one minor cauxin band. These results suggest that 1. cauxin excretion is regulated by sex hormones, such as testosterone, 2. cauxin functions as an esterase in the urine rather than in kidney cells, and 3. the decomposition products by cauxin are excreted in a species-, sex-, and age-dependent manner, as is cauxin itself.  相似文献   
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Summary In Morocco, shellfish sanitary quality analysis does not currently include enteric virus detection. Enteroviruses are classically detected by cell culture, but molecular methods such as RT-PCR are now broadly used alone or associated to cell culture. RT-PCR has the advantage of requiring less time and budget than cell culture. Bivalve mussels, being filter-feeders tend to accumulate viruses in contaminated seawater. In order to assess mussel contamination by enteroviruses, we screened samples of two origins, an aquaculture system and an area where wild mussels grow. Domestic sewage samples from an outlet near the above wild mussels growing area were also analysed. Viruses were concentrated from mussel meat by direct glycine elution and PEG 8000 precipitation. Total RNA was then extracted from the PEG precipitate by the guanidine thiocyanate method and used in RT-PCR. Enterovirus genomes were detected in 10% of wild shellfish samples, whilst none was present in the aquaculture samples. Since organisms harvested in both growing areas are used for human consumption, the enterovirus contamination observed in this study may highlight a potential public health risk and illustrate the importance of including routine virological analysis of shellfish in Morocco.  相似文献   
126.
Saida Hodžić 《Ethnos》2013,78(3):331-360
This article provides a new lens for analyzing power formations in human rights practices by examining Ghanaian struggles over a Domestic Violence Bill. While the hegemonic character of human rights advocacy is well-established, we know less about exercises of power in discourses and practices that oppose rights. I analyze how the Ghanaian government constructed the discourse of cultural sovereignty and deployed it against women's rights. The government legitimated this discourse by appropriating the voice of ‘the people’ and superimposing notions of ‘foreignness’ onto both the Bill and Ghanaian women's rights activists. Drawing on the historiography of colonialism and ethnography of political performance, I argue that this case illustrates how the discourse of cultural sovereignty is mobilized in a struggle over shifting configurations of gender, political activism, and state sovereignty.  相似文献   
127.
On a global scale, cereal grains and animal feed may be contaminated with trichothecenes, such as deoxynivalenol and T-2 toxin, zearalenone (ZEA), and fumonisins, the major mycotoxins of Fusarium fungi. Of these mycotoxins, ZEA is unequivocally implicated in reproductive disorders of swine and other domestic animals. Experiments in vivo and in vitro indicate that ZEA and its metabolites exert estrogenic effects resulting in functional and morphological alterations in reproductive organs. Recently, the potential of trichothecenes and fumonisins to cause reproductive disorders in domestic animals has been investigated. The present review summarizes the toxicological data on the effects of Fusarium mycotoxins on ovarian function, testicular function, placenta and fetus, and puberty/sexual maturity of domestic animals. The results of in vivo animal studies and in vitro tests are reported and discussed.  相似文献   
128.
The fetal adnexa such as umbilical cord, amnion and amniotic fluid have been proposed as ideal sources of different stem cell lineages. Use of adnexal tissue has many potential advantages, including the noninvasive nature of the isolation procedure, the large tissue mass from which cells can be harvested with high efficiency and the potential of these cells to differentiate. Moreover, particularly in human medicine, the harvesting of these tissues is more ethically acceptable making these sources of stem cells very attractive for regenerative therapies and biotechnological applications. The adnexal tissue cells preserve some of the characteristics of the primitive embryonic layers from which they originate. Indeed, many studies indicate that these stem cells exhibit some features of embryonic stem cells as expression of embryonic markers and proliferation capability, without showing immunogenicity. However, the differentiation potential of these cells, either in vivo or in vitro, is intermediate between the pluripotent embryonic stem cells and the multipotent adult stem cells. Non-embryonic extra-fetal derived stem cells have opened new perspectives for developmental biology and for regenerative medicine, not only in humans but also in animals. In this update, we report the state of the art of fetal adnexa-derived stem cells from domestic animals and analyze their applications and potential uses in veterinary medicine.  相似文献   
129.
In search of low-cost eco-tech for the reclamation of municipal domestic wastewater, tomato plants (Lycopersicum esculentum) were cultivated on the floating bed of pulp-free coconut fiber over four different concentrations of wastewater (25%, 50%, 75% and 100%) and groundwater as control, in 10 L plastic bucket for two months. The study revealed that PO4-P was removed by 58.14-74.83% with maximum removal at 50% wastewater. More than 75% removal of NO3-N was observed in all treatments. Both COD and BOD were reclaimed highest at 100% wastewater by 61.38% and 72.03%, respectively. Ammonium-N concentration was subsided below the toxic level in all the treatments. The population of coliform bacteria (Escherichia coli) was reduced to 91.10-92.18% with maximum efficiency at 100% wastewater. Growth performance was observed relatively better at 100% wastewater. Crop production as the value addition of this technology was also recorded maximum at 100% wastewater. The bioaccumulation of Cd and Ni in tomato crop was far below the threshold level, but the bioaccumulation of Pb and Cr was above the safe level by 80 times and 660 times, respectively. The aquaponically reclaimed water can be reused in agriculture, aquaculture and industries.  相似文献   
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