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1.
Parasites of the grey mullet Mugil cephalus collected from Lower K?z?l?rmak Delta in Turkey were investigated. Trichodina puytoraci, Trichodina lepsii, Ligophorus mediterraneus, Ligophorus cephali, Gyrodactylus sp., Microcotyle mugilis, Ascocotyle (Phagicola) longa, Haplosplanchnus pachysomus, Diplostomum spathaceum, Tylodelphys clavata, Posthodiplostomum sp., Neoechinorhyncus agilis and Ergasilus lizae were identified. Overall infection prevalence (%), mean intensity and mean abundance values were 99.61%, 458.10 ± 75.72 and 456.30 ± 75.44, respectively. Infection indices of parasite species in relation to season, lakes/lagoons and some physicochemical parameters of water such as temperature, salinity, dissolved oxygen and nitrate are determined and discussed. Posthodiplostomum sp. is a new parasite record for mugilids and Diplostomum spathaceum is the first record in M. cephalus, in the present study. Moreover, Ligophorus mediterraneus, Ligophorus cephali and Ergasilus lizae are new records for Turkish parasite fauna of fish and Mugil cephalus is a new host record for Neoechinorhyncus agilis in Turkey.  相似文献   
2.
Résumé L'effet des concentrations faibles de l'actionmycine D sur le pourcentage de cellules dans la phase S pendant un contact de longue durée a été étudié dans 4 souches de cellules. Les résultats montrent que le blocage qui a lieu à la fin de G1 n'est que temporaire pour les cellules L-strain, mais qu'il dure plus longtemps pour HEp/2, les fibroblasts de la souris et les cellules du rein du singe.  相似文献   
3.
The main thrust of this study is to consider the problem of simultaneous prediction of actual and average values of the simultaneous equations model through the target function of Shalabh (Bulletin of International Statistical Institute, 1995, 56, 1375–1390). We focus on the predictive performance of the two‐stage ridge estimator with the motivation for eliminating the disorder arising from multicollinearity. An optimal biasing parameter of the two‐stage ridge estimator is derived by a minimization process of prediction mean square error. In addition, an optimal estimator for the weight of observed value in target function is attained theoretically. The results inferred from a numerical example and a Monte Carlo experiment provide a dramatic improvement in the predictive ability of the two‐stage ridge estimator.  相似文献   
4.
Zusammenfassung Feststellung, dass die eindimensionale Diffusions-Methode eine sensitive, einfache und reproduzierbare Technik zur Bestimmung der Veränderungen der fibrinolytischen Aktivität bei Ratten ist.  相似文献   
5.
Zusammenfassung Es wird vorgeschlagen, die Freie-Energie-Funktionen vonHelmholtz undGilbert Lewis alsEnponie undEnchresie zu bezeichnen.  相似文献   
6.
Summary Effects of ether, nembutal or urethane anaesthesia on gastric secretion and mucosal blood flow (MBF) are studied in the Rat; these 3 anaesthetics alter neither volume nor total acidity of juice, but free acidity and proteolytic activity are more importance after ether anaesthesia; MBF is highest in nembutal anaesthetized rats; therefore nembutal is the best anaesthetic for studies of digestive physiology or pharmacology.  相似文献   
7.
Cobalt isopropyl xanthate thin films (CXTFs) were deposited via chemical bath deposition onto different substrates: commercial glass (CG), indium tin oxide (ITO), and poly(methyl methacrylate) (PMM). Isopropyl xanthate was synthesized according to a method described in the literature. The cobalt nitrate and isopropyl xanthate were mixed in a beaker, which allowed the thin films to be deposited via a simple ion-ion mechanism. The transmission, reflectivity, refractive index, dielectric constant, and optical conductivity were investigated for various thin films coated onto different substrates. An ultraviolet-visible spectrophotometer was used to measure the optical properties of the thin films. The lowest value of the transmission and the highest value of the refractive index were observed for the thin films deposited onto PMM. The structure of the cobalt xanthate was characterized by Fourier transform infrared (FTIR) spectroscopy, which was measured using a Perkin-Elmer Spectrum 400 spectrometer. The stretching vibration of the Co-S bonds was observed at 359 cm-1 in the FTIR spectrum of the CXTFs.  相似文献   
8.
How adult tissue stem and niche cells respond to the nutritional state of an organism is not well understood. Here we find that Paneth cells, a key constituent of the mammalian intestinal stem-cell (ISC) niche, augment stem-cell function in response to calorie restriction. Calorie restriction acts by reducing mechanistic target of rapamycin complex 1 (mTORC1) signalling in Paneth cells, and the ISC-enhancing effects of calorie restriction can be mimicked by rapamycin. Calorie intake regulates mTORC1 in Paneth cells, but not ISCs, and forced activation of mTORC1 in Paneth cells during calorie restriction abolishes the ISC-augmenting effects of the niche. Finally, increased expression of bone stromal antigen 1 (Bst1) in Paneth cells—an ectoenzyme that produces the paracrine factor cyclic ADP ribose—mediates the effects of calorie restriction and rapamycin on ISC function. Our findings establish that mTORC1 non-cell-autonomously regulates stem-cell self-renewal, and highlight a significant role of the mammalian intestinal niche in coupling stem-cell function to organismal physiology.  相似文献   
9.
Résumé La teneur et la concentration de la prolactine dans le lobe antérieur de l'hypophyse ont été déterminées aux temps variés de l'oestrus chez la ratte. Dans l'aprèsmidi du jour du pro-oestrus, la teneur et la concentration dans la glande s'abaissent. Ce changement a été bloqué par le pentobarbitrate de sodium injecté par voie i.p. á 13.30 h au jour du pro-oestrus.

We are greatful to Drs.K. Kuretani, H. Nagasawa andR. Yanai, for allowing us to use the microdensitometer (Canalco, Model E) in the Pharmacology Division, The National Cancer Center Research Institute, Tokyo.  相似文献   
10.
Summary The possible release of prostaglandin (PG)-like substances was studied in isolated perfused kidneys from intact and from intrarenal endotoxin (Lipopolysaccharide-LPS)-injected rabbits, using the venous outflow superflow superfuse assay organ technique. Injection of LPS into the renal artery of an LPS-pretreated kidney caused a release of thromboxane A2 (TXA2) and prostacyclin (PGI2)-like materials into the venous effluent as verified by the responses of the specific assay organs. No detectable release of these substances was found in the venous outflow of LPS-injected intact kidney. The possible role of labile cyclo-oxygenase products of arachidonic acid in the Shwartzman reaction is discussed.The authors are indepted to Upjohn, Klamazoo (USA) for the generous gift of PGI2 and to Squibb, New Jersey (USA) for SQ 80338.  相似文献   
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