排序方式： 共有39条查询结果，搜索用时 15 毫秒
31.
As is known from various animal models, the spread of agents causing transmissible spongiform encephalopathies (TSE) after peripheral infection affects peripheral nerves before reaching the central nervous system (CNS) and leading to a fatal end of the disease. The lack of therapeutic approaches for TSE is partially due to the limited amount of information available on the involvement of host biological compartments and processes in the propagation of the infectious agent. The in vivo model presented here can provide information on the spread of the scrapie agent via the peripheral nerves of hamsters under normal and altered axonal conditions. Syrian hamsters were unilaterally footpad (f.p.) infected with scrapie. The results of the spatiotemporal ultrasensitive immunoblot-detection of scrapie-associated prion protein (PrP(Sc)) in serial nerve segments of both distal sciatic nerves could be interpreted as a centripetal and subsequent centrifugal neural spread of PrP(Sc) for this route of infection. In order to determine whether this propagation is dependent on main components in the axonal cytoskeleton (e.g. neurofilaments, also relevant for the component ;a' of slow axonal transport mechanisms), hamsters were treated -in an additional experiment- with the neurotoxin beta,beta-iminodiproprionitrile (IDPN) around the beginning of the scrapie infection. A comparison of the Western blot signals of PrP(Sc) in the ipsilateral and in the subsequently affected contralateral sciatic nerve segments with the results revealed from IDPN-untreated animals at preclinical and clinical stages of the TSE disease, indicated similar amounts of PrP(Sc). Furthermore, the mean survival time was unchanged in both groups. This in vivo model, therefore, suggests that the propagation of PrP(Sc) along peripheral nerves is not dependent on an intact neurofilament component of the axonal cytoskeleton. Additionally, the model indicates that the spread of PrP(Sc) is not mediated by the slow component ;a' of the axonal transport mechanism. 相似文献
32.
33.
A new iridoid glucoside named 10-isovaleroyl-dihydropenstemide (1), along with nine known compounds was isolated from the aerial part of Penstemon campanulatus (Cav.) Willd. The known compounds include three iridoid glucosides, one phenylpropanoid glucoside, one monoterpene glucoside, one monoterpene lactone and three flavonoids. Their structures were elucidated on the basis of spectral evidence. Additionally four phenolic acids as well as a fatty acid were determined through GC-MS analysis. All isolated compounds and the crude extracts were assayed for their antimicrobial activities against six Gram positive and negative bacteria, as well as against three human pathogenic fungi. 相似文献
34.
Hejmej A Wiszniewska B Kosiniak-Kamysz K Sadowska J Bilińska B 《Veterinary journal (London, England : 1997)》2006,171(2):373-379
Distribution of androgen receptors (ARs) in the epididymal duct and prostate of three entire stallions and one bilaterally cryptorchid horse was studied immunohistochemically using a polyclonal rabbit antiserum against the ARs. In both the healthy stallions and the cryptorchid, the epithelial cells of the epididymides showed nuclear staining for ARs. The intensity of AR-staining in the principal cells of the epididymis was stronger than that of the basal cells. In the prostate, the glandular secretory cells were moderately stained whereas the basal cells expressed weak AR-staining. Immunostaining for ARs in the reproductive tissues of the cryptorchid horse was always stronger than in those of the stallions. Our results demonstrate for the first time the AR localisation to equine epididymal and prostatic cells, which are directly regulated by androgens. 相似文献
35.
Gorinstein S Leontowicz M Leontowicz H Jastrzebski Z Drzewiecki J Namiesnik J Zachwieja Z Barton H Tashma Z Katrich E Trakhtenberg S 《Journal of agricultural and food chemistry》2006,54(11):4022-4027
The aim of this investigation was to evaluate the dose-dependent influence of commercial garlic on rats fed cholesterol-containing diets. It was found that commercial garlic contains high concentrations of dietary fibers, microelements, and total polyphenols, and its total antioxidant capacity as determined by two independent assays [1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS)] was similar to that of the original garlic samples. Wistar rats (35) were randomly divided into five diet groups, named control, Chol, Garlic500, Garlic750, and Garlic1000. Control rats were fed basal diet (BD), which included wheat starch, casein, soybean oil, and vitamin and mineral mixtures. To the BD of the Chol group was added 1% of cholesterol. To the BD of the other three groups (Garlic500, Garlic750, and Garlic1000) were added 1% of cholesterol and commercial garlic equal to 500, 750, and 1000 mg of raw garlic per kilogram of animal weight. After 4 weeks of the experiment only in rats from the Garlic500 group were a significant hindering in the rise in plasma lipids and also a significant hindering in a decrease of plasma antioxidant activity registered. A significant decrease in plasma circulating fibrinogen and an increase in the clotting time were found in the same group of rats (P < 0.05 in both cases). The fibrinogenolytic effect of garlic diets was visualized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In the fibrinogen fraction of Garlic500 the 66, 24, and 14 kDa protein bands were detected with weaker protein intensity than in the corresponding ones in the Garlic750 and Garlic1000 diet groups. In conclusion, the positive influences of commercial garlic on plasma lipids, proteins, antioxidant activity, and some indices of blood coagulation are dose-dependent. Therefore, commercial garlic (Elena, Zelazków, Poland) could be a valuable component of atherosclerosis-preventing diets only in optimal doses. 相似文献
36.
Operation safety during sawing operations as well as dimensional accuracy and surface roughness depend on circular saw dynamic
features among other factors such as circular saw blade accuracy and static/dynamic properties of the machine tool. Manufacturers
of saw blades have an obligation to mark tools with a value stating the maximum allowed rotational speed for each saw. However,
in some cases the value indicated on the saw corresponds to the critical rotational speed or is dangerously close to this
critical value. Saw operation at the critical rotational speed is inadvisable and may result in serious injury or depreciation
of product quality. This report outlines a simple methodology for evaluation of circular saw critical rotational speed. The
assessment was conducted with a camera vision technique on the basis of an impulse test. Results are compared with theoretically
calculated critical rotational speeds and the marks on saw blades. 相似文献
37.
38.
39.
11 samples of oats from the 2005 crop of the field experiment carried out in RSD Lipnik were examined. Naked grain oats were represented by a standard Polar cultivar and 5 strains (STH 6102, STH 6856, STH 7146, STH 7256, STH 1692), whereas husked grains were represented by a standard Bohun cultivar and 4 strains (STH 684, STH 688, STH 729, STH 840). The examined naked grain oats differ considerably from husked grain oats in their chemical composition. A statistically significantly higher content of protein (P ≤ 0.05), a higher level of fat (P ≤ 0.01) and a lower value of crude fibre (P ≤ 0.01) were observed in the grains of naked oats compared with the husked grains. The protein of oats is characterised by a favourable amino acid composition of high quality protein which can be confirmed by the EAAI values. The first amino acid limiting the nutritive value of protein was lysine in nearly all oat samples. The characteristic feature of the Polar cultivar was isoleucine deficit. The positive nutritive values for oat grains, in particular those for naked oat grains, make it possible to use them as food for humans and feed for monogastric animals. 相似文献