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251.
Antifreeze proteins (AFPs) and glycoproteins (AFGPs), collectively called AF(G)Ps, constitute a diverse class of proteins found in various Arctic and Antarctic fish, as well as in amphibians, plants, and insects. These compounds possess the ability to inhibit the formation of ice and are therefore essential to the survival of many marine teleost fishes that routinely encounter sub-zero temperatures. Owing to this property, AF(G)Ps have potential applications in many areas such as storage of cells or tissues at low temperature, ice slurries for refrigeration systems, and food storage. In contrast to AFGPs, which are composed of repeated tripeptide units (Ala-Ala-Thr)n with minor sequence variations, AFPs possess very different primary, secondary, and tertiary structures. The isolation and purification of AFGPs is laborious, costly, and often results in mixtures, making characterization difficult. Recent structural investigations into the mechanism by which linear and cyclic AFGPs inhibit ice crystallization have led to significant progress toward the synthesis and assessment of several synthetic mimics of AFGPs. This review article will summarize synthetic AFGP mimics as well as current challenges in designing compounds capable of mimicking AFGPs. It will also cover our recent efforts in exploring whether peptoid mimics can serve as structural and functional mimics of native AFGPs.  相似文献   
252.
Although Trypanosoma evansi is not considered as an important pathogen in pigs, it may interfere with other pathogens or vaccinations by its immunosuppressive nature. In order to determine whether T. evansi alters pig performance and induces immunosuppression in pigs, induction of immune responses by vaccination against classical swine fever (CSF) and by immunization with a control antigen, human serum albumin (HSA), was assessed in T. evansi-infected and non-infected animals. Although T. evansi infection did not have a significant influence on growth performance, feed conversion or PCV, antibody responses against both the test antigen HSA and the CSF vaccine were significantly reduced in T. evansi-infected animals as compared to uninfected animals. Moreover, the reduced response against the CSF vaccine appears to be accompanied by a less well-developed protection against CSF with higher fever responses and leukopenia. This immunosuppression might explain the accounts of poor protection of CSF-vaccinated pigs reported in T. evansi-endemic areas of Vietnam, and suggests that prior treatments with trypanocidal drugs to improve the efficacy of CSF vaccination, may be justified.  相似文献   
253.
Summary The results are presented of 6 years of field trials with weaned Nellore cattle on improved pasture in the midwest of Brazil, using 2 stocking rates and 4 anthelminthic treatment regimes. The most profitable regime included treatments in May, June and September, which yielded an additional 41 and 42 kg of liveweight on the 2 stocking rates. No significant additional gains were obtained by treating during the rainy season, or by treating animals more than 24 months of age. The higher stocking rate (1.8 AU/ha) proved excessive on the improved pasture which deteriorated during the 6 year experimental period, yielding suboptimal liveweight gains.
Efecto De La Tasa De Carga Animal Y Tratamientos Antihelminticos Sobre La Ganancia De Peso De Ganado Destetado Nellore En Pasturas Mejoradas En El Cerrado Brasileno
Resumen Se presentan resultados de 6 años de pruebas con ganado Nellore destetado pastoreando praderas mejoradas en el oriente medio de Brasil, usando 2 tasas de carga animal y 4 regimenes de tratamiento con antihelmínticos. El mejor régimen fue aquel que incluyó tratamientos en mayo, junio y septiembre, mediante el cual se obtuvo 41 y 42 kg adicionales de peso corporal bajo los 2 tipos de carga. No se obtuvo ganancias adicionales cuando los animales se trataron durante la estación lluviosa, o cuando se trataron animales mayores de 24 meses. La carga más alta (1.8 UA/ha) fue deletérea para la pradera mejorada, la que se deterioró durante los 6 años de período experimental, rindiendo tasas inferiores de ganancia de peso.

Influence Des Taux De Charge Et Des Traitements Anthelminthiques Sur Les Gains De Poids De Bovins Nellore Sevres, Entretenus Sur Paturage Ameliore Du Cerrado Bresilien
Résumé Des essais sur le terrain ont été réalisés pendant 6 ans avec des bovins sevrés de race Nellore, sur pâturage amélioré dans le moyen ouest brésilien. Deux taux de charge ont été utilisés et quatre traitements anthelminthiques ont été administrés aux animaux. Les traitements les plus profitables ont été ceux effectués en mai, juin et septembre avec un rendement additionnel de 41 et 42 kg de poids vif avec les deux taux de charge. Aucun gain additionnel significatif n'a été obtenu avec un traitement pendant la saison des pluies, ou chez des animaux âgés de plus de 2 ans. Le taux de charge le lus élevé (1,8 AU/ha) s'est revélé excessif sur le pâturage amélioré qui s'est détérioré pendant les 6 ans d'expérience, avec un rendement inférieur en gain de poids vif.
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254.
Evidence of sympathetic or parasympathetic stimulation of the cardiovascular system has been obtained in dogs under halothane anesthesia following acupuncture. Acupuncture at Jen Chung (Go-26), which is located on the phithrum, results in sympathetic input and an increase in cardiac output, heart rate and mean arterial pressure. These effects can be inhibited by the beta adrenergic blocking agent, propranolol. Acupuncture at Tsu San Li (St-36), which is located distal to the lateral condyle of the tibia, results in parasympathetic input and decrease in cardiac output. This effect is inhibited by atropine.  相似文献   
255.
At the beginning of the 20th century the veterinary relations between Turkey and Germany intensified at the military level. After the Balkan Wars there were urgent attempts to reorganize the army, which lead to the visit of a German military mission under General L. von Sanders, who was appointed to review the army. Along with other members of the German military mission A. Thieme (1881-1949) belonged to the staff of the Turkish Army's Supreme Command as orderly officer and as advisory army veterinarian. During the First World War (1914-1918) there were 44 German veterinary officers, 23 in Turkish and 21 in German uniform. The veterinary officers in Turkish formations were assigned to the military mission, where the veterinary major Dr. K. Dreyer served as official adviser. Moreover mixed German-Turkish special units were formed under German leadership in Turkey, which included German veterinary officers in German uniform. The higher salaries were paid to the German veterinary officers than their Turkish colleagues by the Turkish government. As far as can gathered three German officers perished in Turkey.  相似文献   
256.
Vinclozolin (VCZ) is a systemic dicarboximide fungicide with antiandrogenic activity. Reproductive toxicity of VCZ was investigated in male rats exposed to VCZ during puberty. Sprague-Dawley male rats aged with 35 days were assigned to six different groups; negative control, positive control receiving flutamide (100 mg/kg), VCZ (100, 200 and 400 mg/kg), and a combination of VCZ (200 mg/kg) + methyltestosterone (100 mg/kg). The animals were treated with test compounds by oral gavage daily during 35 to 44 days of age. In pubertal rats sacrificed on the next day after final treatment, VCZ or flutamide-treated group showed a decrease in weights of prostate, epididymis, and seminal vesicle, hypertrophy of Leydig cells in the testis, detached debris and sloughed cells in the tubules of the caput epididymis, and an increase in serum testosterone levels. On the other hand, combined treatment of VCZ + methyltestosterone decreased testicular weight, increased seminal vesicle weight, and induced degeneration of spermatocytes. In adult rats sacrificed at five weeks after final treatment, flutamide decreased testicular sperm counts, and VCZ, flutamide and VCZ + methyltestosterone also decreased epididymal sperm counts. In addition, treatment of VCZ (400 mg) or VCZ + methyltestosterone decreased some motion kinematic parameters of sperms including curvilinear velocity, mean angular displacement and lateral head displacement. Flutamide treatment also decreased lateral head displacement. These results indicate that VCZ exposure during pubertal period in male rats causes reproductive disorders in puberty and adulthood.  相似文献   
257.
Transient expression of phospholipase D1 during heart development in rats   总被引:1,自引:0,他引:1  
The expression of phospholipase D (PLD) isozymes was examined in the hearts of rats at different stages of development. Immunoprecipitation and Western blot analysis revealed weak PLD1 expression in the hearts of day 17 embryos. The level of PLD1 protein increased transiently 0 and 3 days postpartum, and declined gradually beginning 7 days after birth. Immunohistochemistry revealed weak PLD1 immunostaining in some cells at embryonic day 17. In contrast, some vascular endothelial cells and cardiomyocytes were immunostained typically at days 0, 3, and 7 after birth. After postnatal day 21, weak PLD1 expression was immunodetected in some vascular endothelial cells and cardiomyocytes. This suggests that the PLD1 protein in the heart is strongly associated with the early postnatal development of the heart in rats.  相似文献   
258.

In South-East Asia, rice distillers’ by-product (RDP) is a widely abundant feedstuff whose adequate incorporation into pig diets is still questionable. Especially, effects of RDP on nutrient digestibility of growing pigs fed corn-soybean meal-based diet are lacking. The objective of this study was to determine nutrient digestibility and energy value of ordinary (ORDP) and glutinous (GRDP) rice distillers’ by-product in growing pigs. Two groups of 12 castrated crossbred barrows (Duroc × Landrace × Yorkshire), about 3 months old, 38?±?1.04-kg initial body weight, were each allocated to a 15-day experiment in which pigs were divided into three isonitrogenous diet-groups. The animals were housed individually in metabolism cages for separated collection of feces and urine. Each diet-group was provided either a control corn-soybean meal diet or a diet in which corn and soybean meal were partly replaced by ORDP or GRDP at 15 or 30% on diet dry matter basis. Glutinous by-product especially showed higher levels in crude protein, neutral/acid detergent fiber, total branched-chain amino acids, and butyric acid. When compared to the control diet, ORDP tented to increase DM intake (P?= 0.054) but decreased energy (P?< 0.001) and crude protein (P?< 0.04) digestibility, while GRDP decreased DM intake (P?< 0.001). Both GRDP and ORDP products negatively affected digestibility of ether extract. The average digestible and metabolizable energy of ORDP and GRDP were 17.0 and 16.6, and 17.7, and 17.1 MJ/kg DM, respectively. In conclusion, these results show that both RDP, and especially GRDP, are highly valuable protein and energy sources for pig production.

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259.
We trapped a rat (Rattus norvegicus) infected with Capillaria hepatica. At necropsy, grossly yellowish-white nodules (2-3 mm in diameter) were noted to be scattered on the liver''s surface. Microscopically, granulomatous and fibrotic nodules that contained the eggs and/or adult worms of Capillaria hepatica were detected in the liver. Septal fibrosis was diffusely formed throughout the liver. There were a number of ED1-positive macrophages located in the sinusoids of the pseudolobules. On the double staining, myofibroblasts and mast cells were generally observed within the fibrous septa with the mast cells in close proximity to the myofibroblasts. We suggest that the interactions between macrophages, myofibroblasts and mast cells play a role in the septal fibrosis observed in rats infected by Capillaria hepatica.  相似文献   
260.
The objective of this study was to determine the activity of steroid‐ and eicosanoid‐metabolizing enzymes in horses with varying BCSs. The BCSs of twenty non‐pregnant, anoestrous mares were determined prior to euthanasia, and tissue samples were collected from the liver, kidney, adrenal gland, ovary and endometrium. Cytochrome P450 1A (CYP1A), 2C (CYP2C), 3A (CYP3A) and uridine 5′‐diphospho‐glucuronosyltransferase (UGT) activities were determined using luminogenic substrates. The MIXED procedure of SAS was used to test the effect of BCS on enzyme activity and differences between tissues. Activity of CYP1A in adrenals was increased ( .05) in BCS 5 versus BCSs 4 and 6. Activity of CYP1A in the liver was increased (= .05) in BCS 4 versus BCSs 5 and 6. Activity of CYP1A was 100‐fold greater (< .0001) in the liver than in the adrenal, ovary and kidney. Activity of CYP2C was 100‐fold greater (< .0001) in the liver than in the adrenal, ovary and endometrium. Activity of CYP3A was only detectable in the liver. Activity of UGT in the kidney was decreased (= .02) in BCS 4 versus BCSs 5 and 6. Activity of UGT was threefold greater (< .0001) in the liver than in the kidney, whereas activity of UGT was ninefold greater (< .0001) in the kidney than in the ovary and endometrium. In general, BCS did not alter the activity of steroid‐ and eicosanoid‐metabolizing enzymes in horses. However, tissue differences in these enzymes indicated abundant hepatic metabolism in horses, which is similar to other livestock species.  相似文献   
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