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81.
Cohn LA Norris CR Hawkins EC Dye JA Johnson CA Williams KJ 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2004,18(5):632-641
Interstitial lung diseases are a heterogeneous group of disorders with a variety of causes. In veterinary medicine, such lung diseases with a prominent fibrotic component of unknown etiology are often called idiopathic pulmonary fibrosis (IPF). In human medicine, this term is reserved for a distinct disease entity with specific histologic findings labeled as usual interstitial pneumonia (UIP). We identified 23 cats displaying histologic criteria of UIP The purpose of this retrospective study is to describe the presentation and response to therapy of these cats to better define this disease entity. All but 2 cats were middle aged to older (median 8.7 years), with no apparent sex or breed predisposition. Complaints included respiratory distress (n = 18) and cough (13). Duration of signs was less than 6 months in 17 cats. Physical-examination abnormalities included tachypnea, inspiratory or mixed inspiratory and expiratory effort, and adventitial lung sounds. No consistent hematologic or biochemical abnormalities, parasites, or positive serologic results for feline retroviruses, heartworms, or toxoplasmosis were present. Radiographic changes included dense patchy or diffuse interstitial, bronchiolar, and alveolar infiltrates. Analysis of bronchial lavage fluid revealed mild neutrophilic inflammation (n = 6) with no consistent pathogen growth. Clinical condition of 5 cats worsened after lavage. Coincident pulmonary neoplasia was identified in 6 cats. Response to therapy (corticosteroids, antibiotics, bronchodilators, and diuretics) was poor, and most cats died within days to months. Cats with histologic changes compatible with UIP had signs that mimicked many of the clinical findings of human IPF, and treatment response was similarly unrewarding. 相似文献
82.
Perspectives in veterinary medicine: Description and classification of bronchiolar disorders in cats
Carol R. Reinero Isabelle Masseau Megan Grobman Aida Vientos‐Plotts Kurt Williams 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2019,33(3):1201-1221
This Perspectives in Veterinary Medicine article seeks to define, describe putative causes, and discuss key diagnostic tests for primary and secondary bronchiolar disorders to propose a classification scheme in cats with support from a literature review and case examples. The small airways (bronchioles with inner diameters <2 mm), located at the transitional zone between larger conducting airways and the pulmonary acinus, have been overlooked as major contributors to clinical syndromes of respiratory disease in cats. Because the trigger for many bronchiolar disorders is environmental and humans live in a shared environment with similar susceptibility, understanding these diseases in pet cats has relevance to One Health. Thoracic radiography, the major imaging modality used in the diagnostic evaluation of respiratory disease in cats, has low utility in detection of bronchiolar disease. Computed tomography (CT) with paired inspiratory and expiratory scans can detect pathology centered on small airways. In humans, treatment of bronchiolar disorders is not well established because of heterogeneous presentations and often late definitive diagnosis. A review of the human and veterinary medical literature will serve as the basis for a proposed classification scheme in cats. A case series of cats with CT or histopathologic evidence of bronchiolar lesions or both, either as a primary disorder or secondary to extension from large airway disease or interstitial lung disease, will be presented. Future multi‐institutional and multidisciplinary discussions among clinicians, radiologists, and pathologists will help refine and develop this classification scheme to promote early and specific recognition and optimize treatment. 相似文献
83.
Histological and immunohistochemical investigations of ovarian interstitial glands during non‐breeding season in camels (Camelus dromedarius)
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The aim of this was to investigate the histology and immunohistochemistry of interstitial glands during non‐breeding season in camel ovaries. A total of 21 mature, non‐pregnant and apparently healthy camels aged between 8 and 12 years were slaughtered. The ovaries were removed within 15 min, cleaned from adipose tissue, weighted and examined grossly. The histological preparation was made, and then, the blocks were cut at 3–5 microns thickness and stained by H&E for histological examinations. Moreover, some sections were stained with Sudan Black for lipid detection. Immunohistochemical analysis of paraffin‐embedded ovarian tissues was performed to detect the localization of S‐100, vimentin, progesterone receptors (PR) and oestrogen receptors (ER). Immunoreactive signals were detected using UltraVision Detection System. The results revealed that the interstitial glands were located in the cortical region and they were arranged in various arrangements either single, in couple or in groups rich in lipid droplet. All interstitial gland arrangements were enclosed by connective tissue capsules containing fibroblasts and collagenous fibres separated them from the surrounding ovarian structures. Both interstitial glands and their surrounding CT were penetrated by several blood vessels. There was a strong immunoreactive signal for S‐100 in the nuclei of interstitial cells, and no signals were detected either in cells of the interstitial glands or their connective tissue with PR. We could conclude that the interstitial gland is distinct in ovary of camel and further studies are needed to elucidate its rule in steroid synthesis. 相似文献
84.
根据市场需求,研发一种基于无线收发式的客车行李舱门,设计了客车行李舱门的机械结构,论述了客车行李舱门直流推杆电机的控制方法,阐明了客车行李舱门无线收发装置的工作原理,在此基础上完成了客车行李舱门的研发工作,开发出一种新型客车行李舱门。 相似文献
85.
添加剂在猪粪堆肥过程中的作用研究 总被引:10,自引:1,他引:10
添加剂是指为了加快堆肥进程和提高堆肥产品质量,在堆肥物料中加入的微生物、有机或无机物质。本文通过室内培养与室外堆肥试验,研究不同添加剂对猪粪发酵过程中臭味及氮素损失的影响。结果表明,使用本研究中所采用的添加剂与发酵工艺,可以减少猪粪发酵中氨的挥发、氮素损失与猪粪的恶臭。75%含水量的猪粪经过20d的发酵,可达基本腐熟程度。添加剂可以优化堆肥过程的环境条件,提高微生物活性;加快堆肥的腐熟;减少氮素损失,保持养分含量;调节堆肥中各种营养元素的含量,提高堆肥质量。 相似文献
86.
在2007年1月—2007年11月分4个航次对宁波南沙港养殖水域上覆水和表层沉积物间隙水中的溶解无机氮(DIN)和活性磷酸盐(PO4^3--P)浓度进行了现场调查,并应用Fick第一定理对该养殖水域沉积物-水界面DIN和PO4^3--P的扩散通量进行了估算。结果表明,南沙港养殖水域上覆水中NH4^+-N、NO3^--N、NO2^--N和PO4^3--P的浓度变化范围分别为1.07~11.73、0.01~121.43、0.06~3.79μmol·L^-1和0.42~4.16μmol·L^-1;间隙水中NH4^+-N、NO3^--N、NO2^--N和PO4^3--P浓度年变化范围分别为24.00~219.51、4.02~1250.41、0.45~8.70μmol·L^-1和3.41~41.87μmol·L^-1;DIN和PO4^3--P的扩散通量平均值分别为1520.73μmol·m^-2·d^-1和22.33μmol·m^-2·d-^1,扩散方向总体表现为从沉积物向上覆水扩散,每年向养殖系统中输入的DIN和PO4^3--P量分别约为9.87t和0.32t,表明沉积物是南沙港养殖水域水体氮磷营养盐,尤其是DIN的重要的输入源。 相似文献
87.
S. D. VERESOGLOU 《土壤圈》2012,22(2):225-229
The vast majority of herbaceous plants engage into arbuscular mycorrhizal (AM) symbioses and consideration of their mycorrhizal status should be embodied in studies of plant-microbe interactions. To establish reliable AM contrasts, however, a sterilized re-inoculation procedure is commonly adopted. It was questioned whether the specific approach is sufficient for the studies targeting the bacterial domain, specifically nitrifiers, a group of autotrophic, slow growing microbes. In a controlled experiment mycorrhizal and non-mycorrhizal Plantago lanceolata were grown up in compartmentalized pots to study the AM effect on nitrification rates in the plant rhizosphere. Nitrification rates were assayed following an extensive 3-week bacterial equilibration step of the re-inoculated soil and a 13-week plant growth period in a controlled environment. Under these specific conditions, the nitrification potential levels at harvest were exceptionally low, and actual nitrification rates of the root compartment of non-mycorrhizal P. lanceolata were significantly lower than those of any other compartment. It is then argued that the specific effects should be attributed to the alleged higher growth rates of non-mycorrhizal plants that are known to occur early in the AM experiment. It is concluded that the specific experimental approach is not suitable for the study of microbes with slow growth rates. 相似文献
88.
目前,以作物秸秆为原料的沼气工程中存在预处理能耗高、料液分层结壳、混合不均匀、出料困难等问题.该研究采用了自行设计的厢式厌氧消化反应器(CADR),测定了玉米秸秆在中温条件下的沼气产量、甲烷含量以及pH的变化情况.结果表明:玉米秸秆未经C/N调节,只经过简单切割和沼液浸泡两步预处理,即可进行有效的厌氧消化,30 d后进人满负荷运行阶段的产气量为19.94 L·d-1,原料TS产气率为0.495 m3· kg-1,比常规粉碎批式厌氧消化产气率提高了30.75%,pH稳定在6.5 ~7.2之间.采用CADR处理玉米秸秆,启动快速、运行稳定、产气率高. 相似文献
89.
针对目前储能集装箱电池仓电池组工作温度过高及温度一致性不足的问题,通过建立合适的散热系统来维持电池组最佳工作范围以及提高其温度一致性.基于Fluent软件搭建模型,在针对储能集装箱尤其是其电池仓部分的散热系统进行仿真模拟研究的基础上,对储能集装箱安全性及高适应性进行了分析.采用双向风冷作为散热方式,通过温场、流场分析散... 相似文献
90.
Kaushalendra Kumar Jha 《林业研究》2014,25(1):75-86
Teak(Tectona grandis Linn.f.) ranks among the top five tropical hardwood species and is being promoted for use in plantations in its non-native range due to its high economic value.However,there is a general lack of data on ecosystem functioning of teak plantations.We aimed at understanding storage and flux of nutrients related to young plantations of teak.Cycling of nitrogen(N) and phosphorus(P) in a chronosequence of plantations(1,5,11,18,24 and 30 years) was studied in the Moist Deciduous Forest Region of North India with the objective of investigating the nutrient cycling pattern at younger age since the current trend of harvesting age of the species in several tropical countries is being drastically reduced for quick return from this high value crop.Standing state,nutrient uptake,nutrient return and nutrient retranslocation in these plantations were estimated by tree harvesting and chemical analysis methods.The range of total standing nutrient across all these plantations was 20.3 to 586.6 kg·ha-1 for N and 5.3 to 208.8 kg·ha-1 for P.Net uptake of N ranged from 19.4 to 88.9 kg·ha-1·a-1 and P from 3.8 to 18.1 kg·ha-1·a-1.Retranslocation of N and P among all the stands ranged from 8.7 to 48.0 kg·ha-1·a-1 and 0.01 to 3.5 kg·ha-1·a-1,respectively.Range of total nutrient return was 25.8 to 91.3 kg·ha-1·a-1 for N and 2.7 to 10.1 kg·ha-1·a-1 for P.N and P use efficiency was between 107.4 and 192.5 g dry organic matter(OM) g-1 N,and 551.9 and 841.1 g OM g-1 P,respectively.The turnover time ranged from 2.04-13.17 years for N and between 2.40-22.66 years for P.Quantity of N and P in the soil nutrient pool ranged from 2566.8 to 4426.8 kg·ha-1 and 372 to 520 kg·ha-1,Storage and flux of components in different plant parts of different aged plantations were assessed and depicted in compartment models.Percentage storage in soil,litter and vegetation ranged from 82% to 99%,0.6% to 2.4% and 0.5% to 15% for N,respectively,and from 63% to 98%,0.5% to 2% and 1% to 35% for P,respectively.This information could be useful in managing external nutrient manipulation to crops of different ages for optimum biomass production or carbon sequestration. 相似文献