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1.
Removal of the spinal cord is considered time consuming and difficult. A delay in the necropsy procedure, especially in the central nervous system, can result in significant tissue autolysis and subsequent diagnostic difficulties. In the field, where many necropsies are performed, suitable electric saws are mostly unavailable. A technically simple and rapid method for spinal cord removal, requiring only a straightforward tool, has been devised. No necropsy-induced structural damage has been noted on histopathologic examination.  相似文献   
2.
由联合国粮农组织认定的全球重要农业文化遗产(GIAHS)是一类典型的社会生态生产景观(SEPLS),在传统知识传承保护、粮食与食物安全保障、农业生物多样性保护、气候变化应对等诸多方面具有重要意义。为了更好、更有效地开展GIAHS保护及管理工作,本文在分析GIAHS评估重要性和恢复力概念的基础上,以联合国大学(UNU)等团队开发的社会生态生产景观恢复力评估框架(SEPLS模型)为基础,构建了GIAHS恢复力评估框架(GIAHS-RAF),明确了其评估及计算过程。并以中国第1个GIAHS项目——浙江青田稻鱼共生系统(Qingtian Rice-Fish Culture System in Zhejiang Province, RFC)为例,通过对核心保护区——龙现村在2004年(GIAHS项目授牌前)和2016年(GIAHS授牌11年)的恢复力状况进行评估,探讨模型在GIAHS保护成效评估中的适用性。研究结果显示:1)2016年龙现村恢复力整体状况相对较弱,各项资本评估得分为:物质资本(0.75)经济资本(0.63)人类资本(0.61)社会资本(0.57)自然资本(0.38);2)虽然农户收入来源多样且社会经济基础设施能较好地满足社区需求,但是遗产地内部农业物种较少,农户对于系统提供的粮食多样性尚不是非常满意; 3)相较于2004年,经过11年的保护工作,研究区恢复力有所提高,说明GIAHS项目的实施对该遗产的恢复力有积极影响,尤其是物质资本和经济资本两方面。评估结果与该区域相关研究结果及实地调查情况一致,说明所构建的GIAHS恢复力评估框架可以很好地应用于对GIAHS项目及其他相关农业文化遗产的保护成效评估工作。  相似文献   
3.
The antifeedant effect of five organotin compounds (fentin acetate, fentin hydroxide, fentin chloride, cyhexatin and fenbutatin oxide) and of three other compounds known to possess antifeeding activity (guazatine triacetate, 4′-chloroacetophenone isobutyrylhydrazone and thiram) was investigated by feeding treated alfalfa to larvae of Boarmia selenaria. The three fentins and cyhexatin were highly active at 0.1 g litre?1, the order of activity at this concentration being fentin chloride > fentin hydroxide > fentin acetate ? cyhexatin, whereas the other compounds were practically inactive at either this or a somewhat higher concentration (0.5 g litre?1). Guazatine triacetate had a concentration-independent antifeedant effect at much higher concentrations (5–20 g litre?1).  相似文献   
4.
Objective To characterize responses to different doses of propofol in horses pre‐medicated with xylazine. Animals Six adult horses (five females and one male). Methods Each horse was anaesthetized four times with either ketamine or propofol in random order at 1‐week intervals. Horses were pre‐medicated with xylazine (1.1 mg kg?1 IV over a minute), and 5 minutes later anaesthesia was induced with either ketamine (2.2 mg kg?1 IV) or propofol (1, 2 and 4 mg kg?1 IV; low, medium and high doses, respectively). Data were collected continuously (electrocardiogram) or after xylazine administration and at 5, 10 and 15 minutes after anaesthetic induction (arterial pressure, respiratory rate, pH, PaO2, PaCO2 and O2 saturation). Anaesthetic induction and recovery were qualitatively and quantitatively assessed. Results Differences in the quality of anaesthesia were observed; the low dose of propofol resulted in a poorer anaesthetic induction that was insufficient to allow intubation, whereas the high dose produced an excellent quality of induction, free of excitement. Recorded anaesthesia times were similar between propofol at 2 mg kg?1 and ketamine with prolonged and shorter recovery times after the high and low dose of propofol, respectively (p < 0.05; ketamine, 38 ± 7 minutes; propofol 1 mg kg?1, 29 ± 4 minutes; propofol 2 mg kg?1, 37 ± 5 minutes; propofol 4 mg kg?1, 50 ± 7 minutes). Times to regain sternal and standing position were longest with the highest dose of propofol (32 ± 5 and 39 ± 7 minutes, respectively). Both ketamine and propofol reversed bradycardia, sinoatrial, and atrioventricular blocks produced by xylazine. There were no significant alterations in blood pressure but respiratory rate, and PaO2 and O2 saturation were significantly decreased in all groups (p < 0.05). Conclusion The anaesthetic quality produced by the three propofol doses varied; the most desirable effects, which were comparable to those of ketamine, were produced by 2 mg kg?1 propofol.  相似文献   
5.
The present study was conducted in order to verify the efficacy of lower doses and alternative routes of a prostaglandin F2α analogue, luprostiol (PGF), for the induction of luteolysis and the precipitation of estrus in nonlactating Nelore cows (Bos taurus indicus). A conventional dose (15 mg) of PGF was compared to doses lower than the conventional dose, which ranges from 10 to 50%, that were administered intramuscularly (IM), intravulvosubmucosally (IVSM), or in the Bai-hui acupuncture site located within the lumbosacral area. The cows were administered PGF 8 day after estrus in the presence of a corpus luteum, and randomly assigned to the following groups: G1 (positive control), 15 mg, IM (n = 23); G2, 7.5 mg, IM (n = 23); G3, 3.75 mg, IM (n = 24); G4, 7.5 mg, IVSM (n = 25); G5, 3.75 mg, Bai-hui acupoint (n = 24); and G6, 1.5 mg, Bai-hui acupoint (n = 25). The results indicated that 50% of a conventional dose of PGF (7.5 mg) resulted in a complete luteal regression (plasma progesterone <1 ng/ml) at Hour 48, and hastened estrus, regardless of whether or not PGF was administered IM or IVSM. Comparatively, 10 or 25% of the conventional dose, even when administered to the Bai-hui acupoint, resulted in an initial reduction in the concentration of progesterone at Hour 24, followed by an increase observed at Hour 48. In conclusion, 25% of a conventional PGF dose administered via the Bai-hui acupoint proved inadequate to induce a complete luteal regression, whereas 50% of a conventional dose administered IM or IVSM was found to be the minimal dose required to induce effectively a complete luteal regression, and to precipitate the onset of estrus in nonlactating Nelore cows.  相似文献   
6.
The carob tree (Ceratonia siliqua L.) is an important economic resource for Morocco's rural populations. This species is used in reforestation actions and its cultivation in modern orchards is being undertaken to valorize marginal lands and substitute for drought sensitive species. However, little data is available on its intra-specific variability and its adaptability. Morphological characters of pods and seeds from 13 ecoregions of private-domesticated carob were used to assess phenotypic variation of this species. These stands extend from south-west to north-east and cover a wide range of Morocco's ecoregions. Pods length, width, thickness, seeds number, pulp weight, seeds yield and seeds length, width, thickness and weight were measured for 390 trees (30 trees per ecoregion). Statistically significant differences were found between ecoregions for all characters which were examined, what indicates a high phenotypic diversity. Principal component analysis (PCA) and hierarchical cluster of all ecoregions lead to identify two major and opposite groups (the northern ecoregions; and the central and south-western ecoregions). Ecoregions of the north of Morocco exhibited the largest and the thickest pods with the highest pulp weight while other ecoregions have relatively short pods but largest proportion of seed yield. Similarly, the northern ecoregions are characterized by the heaviest seeds. A correlation matrix between morphological characters, geographic parameters and precipitation exhibits a positive and a negative correlation of pods thickness and pulp weight with the latitude and the altitude, respectively. Seed yield and weight are negatively and positively correlated to pod width, pod thickness and pulp weight, respectively. In addition, seed weight is positively correlated with the latitude. The geographic pattern of the carob tree and its variability are discussed in this paper.  相似文献   
7.
Liquefaction of bagasse and cotton stalks was conducted by using polyhydric alcohols (polyethylene glycol PEG#400 and glycerin) in the presence of sulfuric acid (SA) as a catalyst. The effects of different liquefaction conditions, such as ratio raw material/liquefying solvent, effect of PEG#400/glycerin, acid concentration, liquefaction temperature and time on the liquefaction yield have been investigated. The hydroxyl and acid numbers for some liquefied samples were also determined. The results showed that the minimum residue content was obtained at 1/5 raw material to liquefying solvent. PEG#400 alone is not favoured as liquefying solvent as it gives ∼19% residual content for bagasse and ∼22% for cotton stalks at the optimum studied reaction conditions. Replacing 10% of PEG#400 with glycerin as well as increasing the SA concentration, liquefaction temperature or time, decreased the amount of residue for both bagasse and cotton stalks to less than 10%. The hydroxyl number of the produced polyols slowly decreased from 253 to 223 mg KOH/g on extending the reaction time till 120 min and the residual polyols prevented re-condensation of the liquefied components. It seems that this system can be applied on various types of lignocellulosic agricultural residues.  相似文献   
8.
The bioactivity of different formulations of neem seed extracts against the whiteflyBemisia tabaci (Genn.) was assayed in semifield trials during 1992. Tomato plants variety UC-97 were cultivated in pots and left to natural infestation with whitefly in an open field and sprayed with various concentrations of each extract. The high concentrations of all the extracts tested exhibited obvious activity. Also, the different treatments reduced the population density of the adult whiteflies compared with the control. The percentage reduction in the population reached its maximum level one hour after treatment with any tested extract.With one table  相似文献   
9.
The susceptibility of adults of the cabbage aphid,Brevicoryne brassicae and two of the most important predators,Coccinella undecimpunctata andChrysopa carnea to pesticides was assessed. Most of the organophosphorus and carbamate compounds tested were toxic to the aphids. Profenophos was highly toxic to the adult virginoparous aphid at Lc50 level. Malathion demonstrated the highest toxicity to, the aphids. The application of profenophos for the cabbage aphid at Lc50 level exhibited no toxicity forCoccinella but was highly toxic forChrysopa. Pirimicarb proved to be the most selective of the compounds tested for the control of aphids when it was used at a concentration that caused 50% mortality as it was found to be unharmful to bothChrysopa andCoccinella. Dimethoate, on the other hand, was found to be very harmful and highly toxic to bothCoccinella andChrysopa adults and would probably be destructive to those natural enemies in the field. Laboratory evaluation indicates that both pirimicarb and malathion have potentials for use, in IPM program for vegetable pest control.  相似文献   
10.
Crystallization and melting properties of triacylglycerols (TGs) in anhydrous goat's milk fat (AGMF) are investigated by X-ray diffraction as a function of temperature (XRDT) coupled with high-sensitivity differential scanning calorimetry (DSC), using synchrotron radiation and Microcalix. The polymorphic behavior of AGMF was monitored by varying the cooling rates between 5 and 1 degrees C/min from 45 to -20 degrees C with their subsequent melting at 1 degrees C/min. Quenching of AGMF at -20 degrees C was also examined to determine the metastable polymorphic form of AGMF. At intermediate cooling rates, TGs in AGMF crystallize, from about 18 degrees C in two different lamellar structures with triple chain length 3Lalpha stacking of 72 A and a double chain length 2Lalpha stacking of 48 A, which are correlated to two overlapped exothermic peaks recorded by DSC. A reversible transition sub alpha <--> alpha was observed. Subsequent heating at 1 degrees C/min shows numerous structural rearrangements before final melting. At fast cooling of AGMF (5 degrees C/min), similar unstable crystalline varieties are formed while three endotherms are recorded. Several new unstable lamellar structures are observed after quenching. All of these data are compared to those previously reported at slow cooling (0.1 degrees C/min) showing a relative stability of the structures formed. In spite of general similitude, the thermal and structural behavior of the goat's milk is more complex than that of the cow's milk.  相似文献   
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