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51.
52.
Three 0.01m Fe(ClO4)3 Solutions of R= 0, 1, and 2, respectively, were studied over a period of 8 months, where R is referred to the HCO3?/Fe3+ mole ratio in preparation. The R= 0 solution was initially light yellow and clear but rapidly changed to a dense cloudy Suspension after a 9-day induction period. Hydrolysed species rapidly grew from <10 nm to >650 nm. Particles of intermediate size were not observed during the entire period of study. Settleable FeOOH precipi-tate was first observed in 5 weeks with 23 per cent of its iron noted as precipitate at the end of 5 months. The R= 1 and R= 2 Solutions were reddish-brown of low turbidity. Rapid hydrolysis and polymerization were observed immediately after preparation. The hydrolysed species gradually grew in size during ageing and no settleable FeOOH precipitate was observed for at least two years. A hypo-thesis based on Lamb and Jacques's model of Fe3+ hydrolysis is proposed to interpret the reactions taking place in these three Solutions. In the R= 0 solution, the initial number of nuclei for condensation is low, whereas the poten-tial supply of Fe(OH)3 is abundant. In the R= 1 and R= 2 Solutions the number of nuclei initially formed is high, whereas a limited amount of mono-meric Fe(OH)3 is available for condensation. The initial number of nuclei relative to the concentration of monomeric species is the key factor that governs the appearance and properties of these Solutions.  相似文献   
53.
Objective To compare the characteristics of anaesthesia induced with ketamine/medetomidine administered by the subcutaneous and intramuscular routes and to assess the effects of the addition of butorphanol to this combination. Study design Prospective randomised study. Animals Six female New Zealand White rabbits. Methods Rabbits were given one of four combinations of ketamine and medetomidine (K/M) either subcutaneously (SC) or intramuscularly (IM) on four successive occasions with a 7‐day interval between treatments. The dose combinations were; 15/0.25 mg kg?1 SC; 15/0.25 mg kg?1 IM; 15/0.5 mg kg?1 SC, and 15/0.25 mg kg?1 together with 0.4 mg kg?1 butorphanol (K/M/B) SC. The effects of anaesthesia on arterial blood gas values and cardiovascular variables were recorded at predetermined time points. Toe and ear pinch reflexes were judged to determine the duration of surgical anaesthesia. Loss of the righting reflex was used to measure the duration of sleep time. Analyses used repeated measures analysis of variance. Results All groups lost the righting reflex and ear pinch response. Three animals in the groups that received K/M alone lost their toe pinch reflex, whereas four lost this reflex when given K/M/B. Time of onset of loss of the righting, toe and ear pinch reflexes did not differ significantly among the groups. The higher dose combination of medetomidine with ketamine and the combination of K/M/B produced a greater duration of loss of the ear pinch response than the lower dose of K/M administered by either route. No significant differences were found among the groups in the duration of loss of the toe pinch reflex. All animals developed a moderate bradycardia (mean heart rate <166 beats minute?1) and moderate hypoxaemia (mean PaO2 < 6.0 kPa). Animals given butorphanol showed the greatest reduction in respiratory rate (31 ± 13 breaths minute?1, p < 0.05) but this was not reflected in any significant differences in arterial PCO2, PO2 or pH among the groups. Conclusions Administration of K/M by the SC route produced equivalent effects in comparison to intramuscular administration. The addition of butorphanol increased the duration of anaesthesia, but produced a slight increase in the degree of respiratory depression. All dose rates resulted in hypoxaemia so oxygen should be administered when these combinations are used in rabbits. Clinical relevance Subcutaneous administration is both technically simpler and may cause less discomfort to the animal than IM injection, and so is preferred. The combination of K/M with butorphanol has relatively minor effects on the depth and duration of anaesthesia, so offers little advantage to the use of K/M alone.  相似文献   
54.
分析了高校图书馆流通服务和赢利性企业的共性,论述了高校图书馆流通服务管理应用“关键时刻”管理理论的可行性和必要性。提出了通过对高校图书馆流通服务中的一系列“关键时刻”的强化管理.提高流通服务质量,最大限度地满足读者需求的策略。  相似文献   
55.
Abstract

CASE HISTORY: One 4.5-month-old male Border Collie cross presented with aggression and seizures in October 2006. A 16-month-old, female, spayed Border Collie cross presented with hypersalivation and a dropped jaw and rapidly became stuporous in September 2007. The dogs were littermates and developed acute neurological signs 5 and 27 days, respectively, after vaccination with different modified live vaccines containing canine distemper virus.

HISTOPATHOLOGICAL FINDINGS: Sections of brain in both dogs showed evidence of encephalitis mainly centred on the grey matter of brainstem nuclei, where there was extensive and intense parenchymal and perivascular infiltration of histiocytes and lymphocytes. Intra-nuclear and intra-cytoplasmic inclusions typical of distemper were plentiful and there was abundant labelling for canine distemper virus using immunohistochemistry.

DIAGNOSIS: Post-vaccinal canine distemper.

CLINCIAL RELEVANCE: Post-vaccinal canine distemper has mainly been attributed to virulent vaccine virus, but it may also occur in dogs whose immunologic nature makes them susceptible to disease induced by a modified-live vaccine virus that is safe and protective for most dogs.  相似文献   
56.
 为明确一种新的香蕉(Musa sapientum)细菌性叶斑病病原菌,以云南省新平县香蕉园区发现的一种新病害为供试材料,通过分离培养、形态观察、致病性测定、生理生化试验和gyrB,16S rDNA 和 rpoB基因片段分析,对病原菌进行了鉴定。该病由克雷伯氏肺炎球菌肺炎亚种(Klebsiella pneumoniae subsp. pneumoniae)引起,病菌可侵染香蕉叶片、假茎和果实。茎干被病原菌侵入3 d后即可出现黑色小斑点,在接种部位附近呈上下方向蔓延趋势,7 d后茎干上出现大面积棕色坏死,内部组织褐变。本文在世界上首次报道克雷伯氏肺炎球菌肺炎亚种可侵染香蕉植株,引起香蕉细菌性叶斑病。  相似文献   
57.
 华丽腐霉Pythium splendens是我国对外植物检疫对象油棕苗疫病的病原菌,从海南坝王岭自然保护区长臂猿原始林区采集的土样中分离出1株腐霉菌HB0401,经形态特征和核糖体rDNA ITS1序列分析鉴定为华丽腐霉(Pythium splendens Braun)。将该菌株接到健康的油棕苗植株上,能引起典型的油棕苗疫病症状。这是第1次在海南分离到华丽腐霉(Py. splendens)并证实其为油棕苗的致病菌。  相似文献   
58.
The health safety of methylglyoxal (MGO) has been recognized as a key issue owing to its ultra-high reactivity toward some key biomolecules such as amino acids, proteins, DNA, sulfhydryl- and basic nitrogen-containing compounds, including amino-bearing neurotransmitters. In this review, we have summarized the endo- and exogenous sources of MGO and its accumulation inside the body due to high intake, abnormal glucose metabolism and or malfunctioning glyoxalases, and review the debate concerning the adverse functionality of MGO ingested from foods. Higher than normal concentrations of MGO in the circulatory system and tissues have been found to be closely associated with the production of advanced glycation end products (AGEs), increased oxidative stress, elevated inflammation and RAGE (AGE receptors) activity, which subsequently progresses to a pathological stage of human health, such as diabetes complications, cancer, cardiovascular and degenerative diseases. Having illustrated the mechanisms of MGO trapping in vivo, we advocate the development of efficient and efficacious MGO scavengers, either assisting or enhancing the activity of endogenous glyoxalases to facilitate MGO removal, or providing phytochemicals and functional foods containing them, or pharmaceuticals to irreversibly bind MGO and thus form MGO-complexes that are cleared from the body.  相似文献   
59.
60.
Vo, D. T., Hsu, W. H., Abu‐Basha, E. A., Martin, R. J. Insect nicotinic acetylcholine receptor agonists as flea adulticides in small animals. J. vet. Pharmacol. Therap. doi: 10.1111/j.1365‐2885.2010.01160.x. Fleas are significant ectoparasites of small animals. They can be a severe irritant to animals and serve as a vector for a number of infectious diseases. In this article, we discuss the pharmacological characteristics of four insect nicotinic acetylcholine receptor (nAChR) agonists used as flea adulticides in dogs and cats, which include three neonicotinoids (imidacloprid, nitenpyram, and dinotefuran) and a macrocyclic lactone (spinosad). Insect nAChR agonists are one of the most important classes of insecticides, which are used to control sucking insects on both plants and animals. These novel compounds provide a new approach for practitioners to safely and effectively eliminate adult fleas.  相似文献   
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