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981.
The intestine is the primary organ responsible for digestion and absorption of nutrients and is frequently subjected to external environmental stimulations leading to the development of inflammatory bowel disease (IBD), which can cause serious harm to intestinal health in animals. Dietary amino acids play important roles in promoting intestinal development and maintaining intestinal health and exert diverse effects through multiple signaling pathways on the prevention and treatment of IBD, including affecting the physiological activities of intestinal epithelial cells, improving intestinal barrier function, reducing intestinal oxidative damage, regulating the production of inflammatory cytokines, and promoting the expression of endogenous antimicrobial peptides, and involved in main signaling pathways including AMP-activated kinase (AMPK), mammalian target of rapamycin (mTOR), mitogen-activated protein kinase (MAPK), Toll-like receptors (TLRs), nucleotide binding oligomerization domain (NOD)/nuclear factor kappa-B (NF-κB). In this review, basic characteristics of IBD, effects and involved signaling pathways of the amino acids on IBD, and effects and applications of amino acids in maintaining intestinal health in livestock and poultry production were reviewed, so as to provide effective clues and strategies for dietary nutrients in the prevention and treatment of IBD. 相似文献
982.
采用生化、放免、微电子技术等方法,观察了13只实验性脾虚山羊的唾液淀粉酶的活力,血清AchE的活性,尿中VMA,EGG,血浆中cAMP等项指标。结果表明,脾虚山羊的副交感神经机能偏亢,应激能力低,从交感神经中枢到外周再到靶细胞的功能都是处于低下状态。由此提示,山羊的脾虚是机体植物神经机能紊乱的综合征。 相似文献
983.
落叶果树叶片营养模糊诊断法研究 总被引:3,自引:0,他引:3
研究提出了落叶果树“低量、适量、过量”叶片不同营养状态的隶属函数,定义出散温化语气算子和判定化语气算子,以最大隶属度原则为依据,建立了落叶果树营养诊断的模糊模型和用于,苹果,梨诊断的有关参数,计算分析表明,在用于桃,葡萄等树种时,对有关参数进行修正,此模糊诊断模型适用于落叶果树的营养诊断。 相似文献
984.
皖南杉木标准林分蓄积生长阶段划分探讨 总被引:1,自引:0,他引:1
本文通过对几种数学模型的分析,采用了Chapman-Richards函数拟合皖南杉木标准林分蓄积生长过程,证实蓄积生长过程是一组多形而又遵循一定规律变化的曲线,并揭示了一些各指数级蓄积生长的规律。利用数学模型进行生长阶段划分比人为划分更严密。 相似文献
985.
LI Ke-ling WANG Qian GENG Yi-min LI Xiao-hong KANG Hong-jian WEI Min HUANG Qi-fu YAN Jing WANG Wen-rong 《园艺学报》2004,20(2):200-203
AIM: To investigate the therapeutic effects of "Shen Yan Yi Qi Solution", a chinese Medicine, on nephrotoxic serum nephritis in the rat.METHODS: Nephrotoxic serum nephritis model of the rat was set up by the Clarke’s method. RESULTS: Proteinuria and renal insufficiency occurred in all rats after nephrotoxic serum (NTS) injection, but symptoms in treatment group were reduced. At 2nd week, the typical linear deposition of IgG along the glomerular basement membrane (GBM) was observed by fluorescence microscopy. Mesangial hyperplasia and crescent formation in glomeruli were also observed by light microscopy. In treatment group, all the above lesions were alleviated. CONCLUSION: It demonstrated that "Shen Yan Yi Qi Solution" might alleviate the pathological change of glomeruli and improve renal function. 相似文献
986.
Sergeeff JS Armstrong PJ Bunch SE 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2004,18(3):295-300
In this retrospective study, we describe 14 cats diagnosed with hepatic abscesses. The objective of the study was to report the clinical signs, physical examination findings, clinicopathologic findings, and outcomes in affected cats. These findings were then compared with those previously reported in dogs and humans. Clinical signs were vague and included anorexia, lethargy, and weight loss. Only 23% of cats had fever, whereas 31% were hypothermic. Increases in serum activities of alanine aminotransferase and alkaline phosphatase were found in 45 and 18%, respectively, of the 11 cats that had laboratory work performed. Abdominal ultrasound examinations were performed in 7 cats, and abnormalities were found in 71% of them. Four cats had solitary abscesses, all of which were located in the right liver lobes. The other 10 cats had multifocal small abscesses or microabscesses, and all of these cats had clinical signs suggestive of sepsis. Cytologic evaluation of samples obtained by abdominocentesis indicated septic inflammation in 67% of cats in which peritoneal fluid was analyzed. Hepatic abscess cultures yielded polymicrobial growth in 66% of the cats: Escherichia coli was the most commonly cultured organism. Overall mortality rate was 79%. All survivors underwent exploratory laparotomy for partial hepatectomy to resect the abscess followed by medical management. Hepatic abscesses should be considered in cats with signs consistent with sepsis. More routine use of ultrasonography may aid in earlier diagnosis of hepatic abscesses, potentially improving prognosis and outcome. 相似文献
987.
Mungube EO Bauni SM Tenhagen BA Wamae LW Nginyi JM Mugambi JM 《Tropical animal health and production》2006,38(6):475-483
Fasciola gigantica and Stilesia hepatica constrain ruminant productivity. The prevalence and economic losses caused by F. gigantica and S. hepatica in the ruminant production systems of Taveta division of Kenya were estimated in a retrospective appraisal of the slaughter
records on the total number of animals slaughtered and livers condemned over the period 1989 to 2004. Only liver condemnations
based on infestation by F. gigantica and S. hepatica were considered for purposes of this study. Liver condemnation rates differed significantly between bovines, caprines and
ovines (p≤ 0.05) for F. gigantica (26%, 6.6% and 5.2%, respectively) and for S. hepatica (0.4%, 22% and 28%, respectively). The total loss through condemnation of both F. gigantica and S. hepatica infested livers was 4 408 272 KES (Kenyan shillings) (US$ 72 272). The proportion of loss in bovines, caprines and ovines,
was 76%, 17% and 7%, respectively. Fasciolosis contributed 3 505 410 KES (79.5%) and S. hepatica infestation 903 210 KES (20.5%) to the total losses due to liver condemnations. The authors feel strongly that there is a
need for more work on the two parasites using live animals to determine the prevalence in animals of various ages, species
and breeds and the economics of disease control at farm level. 相似文献
988.
Couto CG Lara A Iazbik MC Brooks MB 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2006,20(2):365-370
Veterinarians involved in Greyhound rescue have anecdotally observed that 10-15% of Greyhounds bleed profusely after simple surgical procedures. In most patients, platelet counts and hemostasis profiles are normal; therefore, it is possible that these dogs have platelet dysfunction. The PFA-100 is a novel point-of-care platelet function analyzer that has recently been evaluated as a rapid method to assess platelet function in dogs. The objectives of this study were to characterize platelet function in a group of healthy Greyhounds by means of the PFA-100. Blood samples were collected from the jugular vein from 30 healthy Greyhounds. CBC, biochemical profile, PFA-100 assay with collagen/epinephrine (COL-EPI) and collagen/ adenosindiphosphate (COL-ADP), plasma von Willebrand factor antigen concentration (vWF:Ag), and vWF collagen-binding assay (vWF:CBA) were performed. PFA-100 closure times (CTs) with COL/ADP ranged from 63 to 92 seconds (mean +/- SD, 74.7 +/- 7.9 seconds) and with COL/EPI from 87 to 238 seconds (138 +/- 41 seconds); vWF: Ag ranged from 22 to 120% (87.52 +/- 25.5%) and vWF: CBA ranged from 36 to 102% (77.4 +/- 17.3%); and platelet counts ranged from 147 to 265 x 10(9)/L (194.6 +/- 31.64 x 10(9)/L). Greyhound CTs were significantly shorter than CTs in a mixed population of 50 healthy non-Greyhound dogs, in which the COL/ADP CTs ranged from 61 to 172 seconds (mean +/- SD, 87 +/- 21.6 seconds), and the COL/ EPI CTs ranged from 81 to 300 seconds (mean +/- SD, 183 +/- 67.6 seconds; P = 0.005 for COL/ADP CT; P = 0.001 for COL/ EPI CT). Also, platelet counts were significantly lower (P = 0.001) and packed cell volume was significantly higher (P = 0.001) in the Greyhound than in the non-Greyhound group. The PFA-100 is a reproducible method that can be used in the clinical setting to assess platelet function in Greyhounds; however, normal CTs in healthy Greyhounds are shorter than in other breeds. The results obtained in this study will be used to screen for abnormal platelet function in Greyhounds with postoperative bleeding. 相似文献
989.
990.
Kuszak JR Mazurkiewicz M Jison L Madurski A Ngando A Zoltoski RK 《Veterinary ophthalmology》2006,9(5):266-280
Purpose The results of a recent study on accommodation in humans and baboons has revealed that lens fiber structure and organization are key components of the mechanism of accommodation. Dynamic focusing involves the controlled displacement and replacement, or realignment, of cortical fiber-ends at sutures as the mechanism of accommodation at the fiber level. This emended explanation of the mechanism of accommodation raises the following question: as the structure of crystalline lenses are only similar, not identical between species, is accommodative amplitude related to differences in the structure and organization of fibers between species? To address this question, we have quantitatively examined the structure and organization of fibers in a number of the more commonly used animal models (mice, cattle, frogs, rabbits and chickens) for lens research. Materials and methods Lenses (a minimum of 12–18 lenses/species) from mice, cattle, frogs and rabbits were used for this study. Prior to fixation for structural analysis, measurements of the gross shape of the lenses (equatorial diameter, anterior and posterior minor radii [anterior + posterior minor radius = polar axis]) were taken directly through a stereo surgical dissecting microscope equipped with an ocular reticle. Lenses were then prepared for and examined by light (LM), transmission (TEM) and scanning electron microscopy (SEM). Scale computer-assisted drawings (CADs) of lenses and lens fibers were then constructed from quantitative data as described above and from quantitative data contained in micrographs. Results The differences in fiber structure and organization that effect accommodative range arise early in development and are continued throughout lifelong lens growth. In umbilical suture lenses (avian) secondary fibers develop with almost completely tapered anterior ends (85–90% reduction of their measures of width and thickness at the equator). By comparison, in lenses with line sutures (e.g. frogs and rabbits) secondary fibers develop with just a 50–60% reduction in anterior fiber taper. In lenses with Y sutures (mice and cattle), fiber width taper is only 25–40%. However, in all cases, while the taper of the posterior end width of fibers is just slightly less (approx. 15–20%) than that of anterior ends, posterior end thickness is only reduced by one half that of anterior thickness. Conclusions In humans, the mechanism of accommodation at the fiber level involves the controlled realignment of very flattened and flared, rather than tapered fiber-ends at sutures. In this manner, the simultaneous increase in lens thickness and surface curvature in the accommodated state is the result of fiber-ends being overlapped along multiple (9–12) suture branches covering the majority of the anterior and posterior surfaces. The results of this animal study strongly suggest that accommodative range is directly related to quantitative differences in fiber structure and organization in the different suture types. The very broad accommodative range in birds is made possible, at least in part, by the almost complete tapering of fiber-ends at umbilical sutures. In contrast, the essentially negligible accommodative range of animals that have line- and Y-suture lenses is at least partially the result of the fact that these lenses have fibers with very little end taper. Thus, the blunt ends of fibers in line- and Y-suture lenses precludes any significant overlap of end segments to effect accommodation. 相似文献