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排序方式: 共有126条查询结果,搜索用时 46 毫秒
1.
铬在增强畜禽抗应激与免疫机能中的作用   总被引:3,自引:0,他引:3  
铬是动物所必需的一种微量元素,在动物体内碳水化合物,蛋白质,脂肪的代谢起重要作用。近年来研究发现铬的抗应激和提高免疫机能上有特殊的作用。本文就这一热点问题进行综述。  相似文献   
2.
Rung, K., Riond, J.-L. & Wanner, M. Pharmacokinetics of enrofloxacin and its metabolite ciprofloxacin after intravenous and oral administration of enrofloxacin in dogs. J. vet
Four dogs were given 5 mg/kg body weight enrofloxacin intravenously (i.v.) and orally (p.o.) in a cross-over study. Plasma concentrations of the active ingredient enrofloxacin and its main metabolite ciprofloxacin were determined by a reversed phase liquid chromatographic method. Pharmacokinetic parameters of both substances were calculated by use of statistical moments and were compared to those of enrofloxacin described in the veterinary literature. Mean enrofloxacin t ½λZ was 2.4 h, mean Cls was 27.1 ml/min-kg, and mean Vss was 7.0 1/kg. After i.v. and p.o. administration, concentrations of ciprofloxacin exceeding minimal inhibitory concentrations of several microorganisms were reached (Cmax= 0.2 ng/ml, max = 2.2 h after intravenous administration; Cmax= 0.2 (ig/ml, t max= 3.6 h after oral administration). A considerable part of the antimicrobial activity is due to ciprofloxacin, the main metabolite of enrofloxacin.  相似文献   
3.
All feces produced during 24 h were collected from five pigs and cortisol and immunoreactive cortisol metabolites (CICM), and IgA were quantified. Within pigs, the concentrations of CICM and IgA varied extensively between random samples obtained from a single fecal dropping, and deviated in most cases significantly from the true concentration measured in total fecal output (CV 6.7-130%). The CICM and IgA contents varied considerably (CV 8.1-114%) within and between individual fecal droppings from the same pig compared to the total fecal excretion. In conclusion, single random samples could not be used to reliably quantify the total fecal concentration or excretion of CICM or IgA in pigs. Analyses of all feces collected during shorter periods than 24 h did not provide an accurate estimate of the daily excretion of CICM. Thus, the concentration of stress sensitive molecules in random single fecal samples as an indicator of animal welfare should be interpreted with prudence.  相似文献   
4.
Vascular leakage induced by intradermal injection of endotoxin, zymosan-activated plasma (ZAP) and platelet-activating factor (PAF) was measured in nine Thoroughbreds using 125-iodine human serum albumin (125I-HSA) as a marker in the blood. ZAP and PAF produced dose-dependent increases in vascular permeability with the maximum occurring within the first 15 min after injection. The vascular leakage induced by endotoxin was also dose-dependent, but the maximum occurred 2 h after intradermal injection. Intradermal sites previously injected with endotoxin were refractory to a second injection of endotoxin for up to 5 days. However, sites injected with endotoxin and re-injected with either ZAP or PAF remained responsive with increased vascular leakage compared to saline injected control sites re-injected with either ZAP or PAF. Diminished response to endotoxin challenge may contribute to the poor prognosis of endotoxaemia in the horse.  相似文献   
5.
6.
Topically applied copper phenylbutazone, phenylbutazone, copper salicylate, salicylate and dimethylsulfoxide glycerol (80:20) were investigated as anti-inflammatory agents in rats and horses. Dimethylsulfoxide and glycerol (80:20) or dimethylsulfoxide, ethanol and glycerol (60:20:20) were used as the drug solvents. Subcutaneously administered carrageenin was used to induce inflammatory oedema, either in the paws of rats or the alar fold of the horse. The severity of the oedema and the anti-inflammatory effect of the drugs were assessed by measuring changes in the paw or alar-fold diameters. Copper salicylate and copper phenylbutazone were effective inhibitors of the inflammatory oedema in both species, but dimethylsulfoxide:glycerol (80:20) was not. In the rat, copper salicylate and copper phenylbutazone were superior anti-inflammatory agents compared to either salicylate or phenylbutazone, respectively. Following the topical application of four times the recommended daily dose of copper phenylbutazone to the horse for 5 days, minor skin irritation occurred and trace concentrations of phenylbutazone (maximum 0.6 microgram/ml) and negligible concentrations of oxyphenbutazone and gamma-hydroxyphenylbutazone were detected in the plasma.  相似文献   
7.
海南昌江县燕窝岭石灰岩山体的主要植被型为热带半落叶季雨林.初步调查中发现了两种珍稀濒危植物,它们分别是海南椴(Hainania trichrosperma)与莲桂(Dehaasia hainanensis).当地虽然仍然保留低地树林,但常被利用作采集柴薪与放牧.燕窝岭的岩洞也有被利用作采集燕窝与鸟粪.对燕窝岭自然资源构成最大威胁的是石灰岩开采.本文并对燕窝岭的自然保育与可持续利用提出了建议.  相似文献   
8.
黄瓜根腐病致病病原的鉴定   总被引:6,自引:0,他引:6  
在天津市及周边地区采集病株进行组织分离,同时分离到两类病原菌,经初步的生物学特性鉴定表明,引起黄瓜根腐病的主要病原菌为甜瓜疫霉、尖孢镰刀菌和茄病镰刀菌。经接种试验,认为甜瓜疫霉为主要致病菌。  相似文献   
9.
目的 :观察抗抑郁治疗对不稳定型心绞痛伴抑郁患者近期预后的影响。方法 :将 68例不稳定型心绞痛伴抑郁的患者随机分为抗抑郁治疗组和对照组各 34例 ,治疗组在常规药物治疗基础上予心理治疗及加服抗抑郁药氟西汀 (百忧解 ) 2 0 mg/d,顿服 ,疗程为 1 2周。结果 :治疗组与对照组比较 ,心肌缺血明显改善 (P<0 .0 1 ) ,心绞痛复发率及发生急性心肌梗死比例低 (P<0 .0 5)。结论 :抗抑郁治疗能明显改善不稳定型心绞痛伴抑郁患者的近期预后。  相似文献   
10.
The Sun's outer atmosphere, or corona, is heated to millions of degrees, considerably hotter than its surface or photosphere. Explanations for this enigma typically invoke the deposition in the corona of nonthermal energy generated by magnetoconvection. However, the coronal heating mechanism remains unknown. We used observations from the Solar Dynamics Observatory and the Hinode solar physics mission to reveal a ubiquitous coronal mass supply in which chromospheric plasma in fountainlike jets or spicules is accelerated upward into the corona, with much of the plasma heated to temperatures between ~0.02 and 0.1 million kelvin (MK) and a small but sufficient fraction to temperatures above 1 MK. These observations provide constraints on the coronal heating mechanism(s) and highlight the importance of the interface region between photosphere and corona.  相似文献   
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