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71.
A comparison was made between different anaesthetics for general anaesthesia in growing pigs, with focus on minor surgery under field conditions and for experiments in clinical research. Healthy crossbreed pigs (HampshirexYorkshirexSwedish Landrace) weighing 20–45 kg were used. The anaesthetics combinations compared were 1) azaperone plus metomidate (AM), 2) Zoletil® (zolazepam + tiletamine) plus xylazine (ZX), and 3) Zoletil® plus xylazine plus ketamine (ZXK). Parameters measured were: heart rate, respiratory rate, blood pressure, body temperature, and depth of analgesia (pin-prick). Minor surgery was performed to test the reliability of the “pin-prick” tests. It was clearly shown that AM produces anaesthesia with good cardiovascular stability and is a drug combination that is suitable for minor surgery. ZX also produces a good anaesthesia characterized by reliable and rapid induction. Good cardiovascular function is maintained, and the laryngeal relaxation makes intubation possible. These characteristics are very useful in a laboratory environment, as easy handling to avoid stress is necessary for research. Although it is difficult to evaluate the quality of analgesia from this study, it is concluded that ZX did not provide a superior anasthesia and analgesia compared to AM in crossbreed pigs. However, these drugs are too expensive for regular use in ambulatory practice. The effects of ZXK resemble those of ZX, but the ZXK-drug combination has no anaesthetic advantages and is more laborious to work with. kw|Keywords|k]azaperone; k]metomidate; k]Zoletil®, xylazine; k]ketamine 相似文献
72.
The effects of pH and aluminium on embryonic and early larval stages of Swedish brown frogs Rana arvalis, R. temporaria and R. dalmatina were tested in laboratory bioassays. In all three species egg mortality and time needed for embryonic development to hatching increased when pH declined, but no significant effects were found on embryonic development when aluminium level was elevated. In R. arvalis and R. temporaria larval mortality was affected by both pH and aluminium. In both species the frequency of occurrence of larval deformities increased in acid water, and there was a synergistic effect of pH and aluminium. In R. arvalis swimming behaviour was disturbed by high levels of aluminium at pH 5. In all three species the frequency of stressed larvae increased when pH was depressed and aluminium concentration elevated, and there was a synergistic effect when both were combined. The three species differed significantly in egg mortality, time needed for embryonic development, larval mortality, larval deformities and larval stress al low pH and high aluminium levels. R. arvalis showed the highest acid tolerance and R. dalmatina was the most sensitive to low pH. 相似文献
73.
74.
Ray C. Henrikson 《Cell and tissue research》1973,140(4):445-449
Summary The ultrastructure of the cecal epithelium of the mouse resembles that of more distal parts of the colon. A brief discussion is presented of the possible significance of apical cytoplasmic granules to the glycocalyx and of the close association of microorganisms with the lining epithelium.This research was supported by N.I.H. grant GM-15289. The author thanks Dr. F. J. Agate for the scanning electron micrograph. 相似文献
75.
76.
JUAN ANTONIO DÍAZ‐PENDÓN M. CARMEN CAÑIZARES ENRIQUE MORIONES EDUARDO R. BEJARANO HENRYK CZOSNEK JESÚS NAVAS‐CASTILLO 《Molecular Plant Pathology》2010,11(4):441-450
Tomato yellow leaf curl disease (TYLCD) is one of the most devastating viral diseases affecting tomato crops in tropical, subtropical and temperate regions of the world. Here, we focus on the interactions through recombination between the different begomovirus species causing TYLCD, provide an overview of the interactions with the cellular genes involved in viral replication, and highlight recent progress on the relationships between these viruses and their vector, the whitefly Bemisia tabaci. Taxonomy: The tomato yellow leaf curl virus‐like viruses (TYLCVs) are a complex of begomoviruses (family Geminiviridae, genus Begomovirus) including 10 accepted species: Tomato yellow leaf curl Axarquia virus (TYLCAxV), Tomato yellow leaf curl China virus (TYLCCNV), Tomato yellow leaf curl Guangdong virus (TYLCGuV), Tomato yellow leaf curl Indonesia virus (TYLCIDV), Tomato yellow leaf curl Kanchanaburi virus (TYLVKaV), Tomato yellow leaf curl Malaga virus (TYLCMalV), Tomato yellow leaf curl Mali virus (TYLCMLV), Tomato yellow leaf curl Sardinia virus (TYLCSV), Tomato yellow leaf curl Thailand virus (TYLCTHV), Tomato yellow leaf curl Vietnam virus (TYLCVNV) and Tomato yellow leaf curl virus(TYLCV). We follow the species demarcation criteria of the International Committee on Taxonomy of Viruses (ICTV), the most important of which is an 89% nucleotide identity threshold between full‐length DNA‐A component nucleotide sequences for begomovirus species. Strains of a species are defined by a 93% nucleotide identity threshold. Host range: The primary host of TYLCVs is tomato (Solanum lycopersicum), but they can also naturally infect other crops [common bean (Phaseolus vulgaris), sweet pepper (Capsicum annuum), chilli pepper (C. chinense) and tobacco (Nicotiana tabacum)], a number of ornamentals [petunia (Petunia×hybrida) and lisianthus (Eustoma grandiflora)], as well as common weeds (Solanum nigrum and Datura stramonium). TYLCVs also infect the experimental host Nicotiana benthamiana. Disease symptoms: Infected tomato plants are stunted or dwarfed, with leaflets rolled upwards and inwards; young leaves are slightly chlorotic; in recently infected plants, fruits might not be produced or, if produced, are small and unmarketable. In common bean, some TYLCVs produce the bean leaf crumple disease, with thickening, epinasty, crumpling, blade reduction and upward curling of leaves, as well as abnormal shoot proliferation and internode reduction; the very small leaves result in a bushy appearance. 相似文献
77.
Simon Brooker Archie CA Clements Peter J Hotez Simon I Hay Andrew J Tatem Donald AP Bundy Robert W Snow 《Malaria journal》2006,5(1):1-8
Background
On the island of Bioko (Equatorial Guinea), insecticide-treated nets (ITNs) have been the main tool used to control malaria over the last 13 years. In 2004, started an indoor residual spraying (IRS) campaign to control malaria. The purpose of this study is to asses the impact of the two control strategies on the island of Bioko (Equatorial Guinea), with regards to Plasmodium infection and anaemia in the children under five years of age.Methods
Two transversal studies, the first one prior to the start of the IRS campaign and the second one year later. Sampling was carried out by stratified clusters. Malaria infection was measured by means of thick and thin film, and the packed cell volume (PCV) percentage. Data related to ITN use and information regarding IRS were collected. The Pearson's chi-square and logistic regression statistical tests were used to calculate odds ratios (OR)Results
In the first survey, 168 children were sampled and 433 children in the second one. The prevalence of infection was 40% in 2004, and significantly lower at 21.7% in 2005. PCV was 41% and 39%, respectively. 58% of the children surveyed in 2004 and 44.3% in 2005 had slept under an ITN. 78% of the dwellings studied in 2005 had been sprayed. In the 2005 survey, sleeping without a mosquito net meant a risk of infection 3 times greater than sleeping protected with a net hanged correctly and with no holes (p < 0.05).Conclusion
IRS and ITNs have proven to be effective control strategies on the island of Bioko. The choice of one or other strategy is, above all, a question of operational feasibility and availability of local resources. 相似文献78.
The evolution of animal and plant vascular systems played a pivotal role in the advancement from simple to complex organisms, through the provision of a delivery system for the distribution 相似文献
79.
目的:目前认为,十二指肠胆道反流是引起胆道反复感染,进而导致胆道结石再发和胆道狭窄的原因之一。近年来应用以内镜下逆行胆胰管造影术(endoscopicretrogradecholangiopancreatography,ERCP)为基础的微创治疗胆总管结束的技术开展颇为广泛。它主要包括ERCP、Oddi括约肌切开术(endoscopicsphincterotomy,EST)、十二指肠乳头球囊扩张术(endoscopicpapillarybal—Iondilation,EPBD)、胆管结石碎石取石术、胆总管支架植入术和鼻胆管引流术六大技术。本文主要研究了采用不同术式的EST,即EST中切口和EST小切口+EPBD术,在术后早期对患者十二指肠胆道反流的影响。方法:63例胆总管结石患者,男30例,女33例,予行经内镜下逆行的胆胰管造影(ERCP)后分别采用不同术式EST,术后安放胆总管引流管。术后l周留取胆汁采用口服核素和测定胆汁中的胃蛋白酶I、II的浓度,对十二指肠胆道反流进行定量和定性的测定。结果:EST中切口术组、EST小切口+球囊扩张(EPBD)组分别与无EST组相比,年龄和性别无统计学意义(P=0.07,P=0.416)。行EST中切开和小切开+球囊扩张患者胆汁中的锝计数明显高于无EST组,且这两组不同术式的患者锝计数存在显著的统计学差异(P〈0.05)。行EST中切口者、EST小切口+球囊扩张术者胆汁中的PGII质量浓度明显低于无EST组(P〈0.05),但是EST中切口者和EST小切口+球囊扩张术后两组间胆汁中PGII的质量浓度无统计学差异。结论:行EST中切口取胆总管结石的患者在手术早期较易发生十二指肠胆道的反流。因此,建议对于胆总管结石患者尽量选择行EST小切口+球裳扩张术(EPBD)的手术方式。 相似文献
80.
苎麻光合生理生态特性研究 总被引:1,自引:0,他引:1
以大田栽培的苎麻植株为材料,用TPS-2便携式光合作用测定系统测定自然条件下生长的苎麻叶片的光合气体交换参数,以及光响应曲线和CO2响应曲线,并通过回归和相关法分析探讨净光合速率与主要生理、生态因子间的关系.结果表明:(1)苎麻叶片的净光合速率(Pn)日变化曲线呈现双峰型,2个光合峰高度接近,其净光合速率具有典型的午休"现象;蒸腾速率(Tr)日变化曲线呈现单峰型,其走势与气孔导度(Gs)日变化一致.(2)苎麻叶片光合作用的光饱和点(LSP)为1 568.5μmol?m-2?s-1,光补偿点(LCP)为54.18μmol?m-2?s-1,表观量子效率(AQY)为0.025 8 mol?mol-1;而其CO2补偿点(CCP)、饱和点(CSP)和羧化效率(CE)分别为49.25、1 746.9μmol?mol-1和0.045;因此,苎麻属于喜光性阳生植物,且对强光有一定的耐受能力.(3)苎麻叶片Pn日变化的主要限制因子是胞间CO2浓度(Ci),主要决定生理因子是气孔导度(Gs). 相似文献