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In mammalian ovaries, the majority of follicles are lost before ovulation by atresia. This degenerative process is initiated or caused by granulosa cell apoptosis. To reveal the androgen-dependent mechanism of selective follicular atresia, the culture model system for agonism and antagonism of the androgen receptor has been established. We examined the influence of an androgen receptor antagonist, 2-hydroxyflutamide (2-Hf), on the incidence of apoptosis in cultured porcine granulosa cells. They were incubated (6 and 12-h) in the presence of testosterone (T, 10(-7)M), 2-Hf (1.7×10(-4) M) or both T and 2-Hf (T+2-Hf), and then analyzed by flow cytometry with fluorescein labelled annexin V. To better imitate in vivo conditions, the intact porcine follicles (6-8 mm in diameter) have been incubated in an organ culture system with the addition of the same factors. Sections obtained from follicles fixed after culture were stained with hematoxylin and eosin, and the presence of apoptosis-related DNA strand breaks was evaluated by the TUNEL method. Estradiol and progesterone concentrations in the culture media were measured by radioimmunoassays. The addition of T or 2-Hf to the culture media caused an increase in the number of apoptotic granulosa cells, while treatment with T+2-Hf decreased it in both in vitro and organotypic models. Follicles cultured with the addition of T or 2-Hf exhibited morphological changes indicating follicular atresia. Granulosal estradiol secretion was considerably stimulated by T+2-Hf. The highest increase in follicular estradiol secretion was observed after the anti-androgen addition. In both granulosal and follicular cultures, the production of progesterone declined in the presence of T or 2-Hf but increased after their simultaneous addition. In conclusion, androgen receptor antagonist 2-Hf attenuates induction of granulosa cell apoptosis in the presence of a high T level. The nature of this protective mechanism as yet is unknown and requires further research.  相似文献   
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对来自波兰及英国的2个相同品种的油菜种子样品进行了健康测试,并重点观察了油菜黑胫病病原菌(Letosphoeria maculans/Phoma lingam)感染的程度及菌系类型。结果表明来自2个国家的种子都一定程度受微生物感染,品种间差异不大,所检测到的较多的菌属为Alternaria,Fusarium及Penicillium。黑胫病病原菌感染的百分率波兰种子样品平均为0.5%,英国种子样品平均为0.6%,菌系鉴定表明,7.1%的波兰株系及12.3%的英国株系为强致病的Tox 类型。此外,还发现健康测试前种子表面消毒可提高黑胫病病原菌的检出率。  相似文献   
55.
The alkali extractable (AE) arabinoxylans from two rye flours differing in baking quality were studied following sequential extraction of water-unextractable and starch-free rye flour residue with saturated barium hydroxide solution, water and 1 M sodium hydroxide solution (Ba, BaH, and Na, respectively), and further fractionation of isolated fractions by ammonium sulfate precipitation. (1)H NMR and sugar analyses of AE subfractions provided evidence for the presence of lowly branched arabinoxylans (average arabinose-to-xylose ratio, Ara/Xyl approximately 0.5), containing mainly un- and monosubstituted xylopyranosyl residues (Xylp) in the chain. The proportion of this subfraction decreased from 50% in the Ba fraction to 35 and 17% in the Na and BaH fractions, respectively. Other subfractions, rich in both mono- and disubstituted Xylp, represented arabinoxylan populations with intermediate (Ara/Xyl approximately 0.8) and high substitution degree (Ara/Xyl approximately 1.1). The Ba and Na fractions contained phenolic compounds, whereas they were absent in the BaH fraction. The higher ratio of such phenolic compounds to arabinose (PhC/Ara) found in AE arabinoxylans from rye flour of inferior baking quality was one of the most pronounced differences between arabinoxylan populations from rye flours with high and low baking quality. The arabinoxylans from rye flour of high baking quality present in Ba and Na fractions had slightly higher apparent molecular weights (MWs) when compared to those from rye flour with low baking quality. The arabinoxylans present in the BaH fractions, characterized by the highest MWs, had similar MWs.  相似文献   
56.
Information on 10 species (with a total of 732 individuals) of insects, belonging to orders Hymenoptera, Lepidoptera and Diptera is given. Insects were obtained from cones ofPicea abies (L.) Karst. collected in 1992 in Bia?owie?a Management Unit in north-eastern range of Norway spruce in Poland.  相似文献   
57.
Cystic structures are often seen during ultrasound examination of the internal genitalia of stallions. They are located between the ampullae of deferent ducts, either within the urogenital fold, or under the isthmus of the prostate (uterus masculinus). Occasionally, cystic dilatations are also found more caudally, behind the prostate, at the colliculus seminalis (urethral cyst, utriculus masculinus). These cysts are detected less frequently during routine examinations, possibly because of the fact that this area is screened less carefully for the pathologies than the more proximal portion of the internal reproductive tract of stallions. We have recently noticed that many stallions with ejaculatory problems have large cysts at the colliculus seminalis. This article describes the typical clinical presentation of these cases, diagnostic procedures, and management. In addition, we discuss the discrepancies in the currently used terminology pertinent to this condition, as well as introducing a new term, which seems to best describe the root cause of this disorder. Finally, this article presents new diagnostic and therapeutic options used in human medicine in similar cases, and proposes to investigate the applications of these methods in veterinary medicine.  相似文献   
58.
The riboflavin content in extruded coelomocyte lysates derived from Dendrodrilus rubidus may serve as a sensitive bioindicator of soil metal pollution: the vitamin (B2) content has previously been found to be high in worms from unpolluted soil but low in worms inhabiting Zn/Pb mine soils, aerially deposited Ni-contaminated soil, and in worms experimentally transferred from clean soil to the metalliferous field soils. The aim of the present work was to extend these observations by comparing the number and riboflavin composition of coelomocytes retrieved from three lumbricid species (Allolobophora chlorotica, Dendrobaena veneta, Eisenia andrei) after 4-week exposures to an unpolluted commercial soil, two geochemically contrasting unpolluted field soils, and two different Zn/Pb/Cd-polluted soils from the Bukowno district in South Poland. Whilst eco-physiologically contrasting, these three earthworm species share the trait of possessing relatively high numbers of eleocytes, a category of immune-competent coelomocyte rich in autofluorescent riboflavin. Spectroflurometric analysis indicated that coelomocyte riboflavin content in worms maintained in strongly metalliferous soils or in unpolluted sandy-clay and loamy-sand soils was increased in coleomocytes from epigeic D. veneta and E. andrei species, whilst was decreased in endogeic A. chlorotica. In conclusion, the riboflavin content of earthworm coelomocytes is affected in species-specific ways by edaphic variables, including organic matter and metal pollution.  相似文献   
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The water-extractable arabinoxylans (WE AXs) present in rye bread govern its viscous properties, which may be related to reduced risk of cardiovascular diseases and diabetes. Breads made from rye cultivars generally exhibit higher AX-dependent extract viscosities (Cyran, M. R.; Saulnier, L. Food Chemistry2012, 131, 667-676) when compared with those produced from inbred lines used for their breeding. To give further details about this trend, the WE AXs were isolated from breads of lines and structurally characterized by HPSEC and (1)H NMR spectroscopy. The extract viscosities of endosperm and whole-meal breads were usually comparable, in contrast to those made from rye cultivars with higher viscosity of endosperm bread. The WE AXs present in breads obtained from inbred lines were characterized by the higher degradation degrees than those in breads from cultivars, as indicated by their HPSEC-RI profiles. This was associated with considerably lower proportions of 2-Xylp in their backbones. Besides, a level of endoxylanase activity in flours from inbred lines was much higher than that in flours from cultivars. Breeding of hybrid rye cultivars for production of high-viscosity bread requires the proper components. They may be preliminarily selected from populations with high WE AX contents and relatively low levels of endoxylanase activity by using the overall viscosity test for starting flours. However, further measurement of AX-dependent extract viscosity in test breads made from such lines may verify their usefulness completely.  相似文献   
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