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1.
The effect of prey species and the different stages of prey on the predatory efficiency and biology of the phytoseiid mites,Amblyseius gossipi Elbadry andTyphlodromus mangiferus sp. n. was studied. It was found that feeding either predator onTetranychus cucurbitacearum (Sayed) promoted faster development and a higher rate of oviposition than rearing on the twospotted spider mite,T. urticae (Koch). Different stages of both prey species also produced different responses in the biological activities of these predaceous mites.
Résumé On a étudié l'effet de l'espèce de la proie et de ses différents stades sur l'efficacité et la biologie des acariens phytoseiides,Amblyseius gossipi Elbadry etTyphlodromus mangiferus sp. n. Il a été constaté que l'alimentation des 2 prédateurs avecTetranychus cucurbitacearus (Sayed) assure un dévelopment plus rapide et une fécondité plus élevée que leur élevage surT. urticae (Koch). Les différents stades de ces 2 proies produisent des réponses différentes dans les activités biologiques des 2 acariens prédateurs.
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2.
The reptile fauna of Romania comprises 23 species, out of which 12 species reach here the limit of their geographic range. We compiled and updated a national database of the reptile species occurrences from a variety of sources including our own field surveys, personal communication from specialists, museum collections and the scientific literature. The occurrence records were georeferenced and stored in a geodatabase for additional analysis of their spatial patterns. The spatial analysis revealed a biased sampling effort concentrated in various protected areas, and deficient in the vast agricultural areas of the southern part of Romania. The patterns of species richness showed a higher number of species in the warmer and drier regions, and a relatively low number of species in the rest of the country. Our database provides a starting point for further analyses, and represents a reliable tool for drafting conservation plans.  相似文献   
3.
A single dose of zearalenone (10 g/g LBW) was injected intraperitoneally to Wistar Albino rats at the age of 50–100 days. The uterine acetyl cholinesterase enzyme was significantly increased in the treated animals compared to that in the controls. Therefore, zearalenone would be considered as an esterogenic effector for increasing the uterine acetyl cholinesterase which enhances uterine relaxation and subsequently improves its function for pregnancy in prematured-animals.Unlike estradiol, it was interesting to find that the estrogenicity of zearalenone was increased by the moderating progesterone hormone. Moreover, it was revealed in this study that the injected dose of zearalenone had no deleterious effects on the pregnant rats at 10–12 days period of gestation. The harmful effects of zearalenone on pregnant animals cited in the literature (11, 13, 19) were reviewed.  相似文献   
4.
Serial concentrations of aflatoxin B1 ranging from 200 to 1500 p.p.b. in 2% lactic acid solution (which is the aimed concentration of lactic acid in fresh silage) were assayed for detoxification. Thin-layer chromatography analysis, revealed a complete transformation of 1 000 p.p.b. of aflatoxin B1 to a new fluorescing compount corresponding to aflatoxin B2a which is referred to as hydroxydihydro-aflatoxin B1 toxicity test on chickens confirmed Ciegler's findings (4). The results confirm that the chemical changes taken place in the silo can detoxify aflatoxin B1 to aflatoxin B2a.  相似文献   
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6.
Cytological characteristics and pattern of distribution of different cell types in the epithelia of cervix and uterus of crab-eating macaque (Macaca fascicularis) in follicular and luteal phases of the menstrual cyclic and amenorrhea were studied. The cervix uteri and uterus exhibit remarkable structural differenes in the ciliated, secretory, and ciliated-secretory cells. Since the number of ciliated-sexretory cells in the uterus is higher than in the cervix. It is believed that they form an additional source for the secretion of uterine fluid during the menstrual cylce. Both ciliated and secretory cells undergo degeneration; extensive cytoplasmic vacuolation associated with pycnosis and disorganization of the nuclei encountered.  相似文献   
7.
This work was conducted in order to study the kinetic behaviour of dietary aflatoxins in the colostrum of a pregnant cow exposed to contaminated feeds for a short period.In this study, two pregnant cows received a single dose of dietary aflatoxins in the form of rice powder contained 31.20 ppm aflatoxin B and 19.68 ppm aflatoxin G during the last stage of pregnancy, at about two weeks before parturition.Samples of colostrum were collected from dams and assayed for the presence of toxic metabolites as well as its conjugations by electrophoretic analysis.The results revealed that the intake of aflatoxins appeared in the colostrum pospartum as AFM1 and also AFB2a which is a non toxic metabolite. Moreover, it was found that the excreted metabolites including AFB2a were conjugated to the immunoglobulin protein fraction of the colostrum.The significance of the obtained results to the newborn calf are discussed.  相似文献   
8.
Among eight species of mammals in this study (cattle, sheep, pig-tail and rhesus monkeys, rabbit, pig, rat, and dog) four basic patterns of anatomical structure at the uterotubal junction are described. The classification of types is based upon the presence or absence of an intramural portion of the oviduct and of isthmal folds or plicae projecting into the lumen of the uterine cornu. Histological variations are reported for three tissues: epithelial and connective of the mucosa and smooth muscle of the tunica muscularis. In the epithelium during the estrous cycle the differences recorded include: (a) absence of ciliated cells in the distal end of the oviduct in rat and dog; (b) variations in ciliated and nonciliated cells in (1) cell height, (2) location, shape and stainability of the nucleus, and (3) in amount and stainability of apical cytoplasm; (c) presence of lymphoblast-like cells which appear to migrate through the epithelium from the lamina propria. The connective tissue of the mucosa, as a circular layer and as cores for the mucosal folds, shows variations in thickness and in relative density of cells and fibers of the matrix. Emphasis is given to the presence of an inner longitudinal layer of smooth muscle in the tunica muscularis of the distal oviduct in six of the eight species.  相似文献   
9.
The mitochondrial contact site and cristae organization system (MICOS) mediates the formation of cristae, invaginations in the mitochondrial inner membrane. The highly diverged MICOS complex of the parasitic protist Trypanosoma brucei consists of nine subunits. Except for two Mic10‐like and a Mic60‐like protein, all subunits are specific for kinetoplastids. Here, we determined on a proteome‐wide scale how ablation of individual MICOS subunits affects the levels of the other subunits. The results reveal co‐regulation of TbMic10‐1, TbMic10‐2, TbMic16 and TbMic60, suggesting that these nonessential, integral inner membrane proteins form an interdependent network. Moreover, the ablation of TbMic34 and TbMic32 reveals another network consisting of the essential, intermembrane space‐localized TbMic20, TbMic32, TbMic34 and TbMic40, all of which are peripherally associated with the inner membrane. The downregulation of TbMic20, TbMic32 and TbMic34 also interferes with mitochondrial protein import and reduces the size of the TbMic10‐containing complexes. Thus, the diverged MICOS of trypanosomes contains two subcomplexes: a nonessential membrane‐integrated one, organized around the conserved Mic10 and Mic60, that mediates cristae formation, and an essential membrane‐peripheral one consisting of four kinetoplastid‐specific subunits, that is required for import of intermembrane space proteins.  相似文献   
10.
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