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111.
112.
The results of 382 cytological examinations in dogs and 118 in cats were retrospectively compared with the correlating histological results.The histological diagnosis represented the gold standard. The investigation comprised skin, lymph node and spleen samples. The aim was to estimate the diagnostic value and the limits of cytological examinations in relation to the type of the changes. The cases were grouped in six categories: Corresponding diagnoses were formulated in 201 cases. In lymph node samples, they were reached almost twice as frequently than in skin and spleen samples. Round cell neoplasias (mast cell tumours, canine cutaneous histiocytomas and malignant lymphomas) were most often subclassified. Cytological diagnoses lacking subclassification were reached in 98 cases. The lesions were cytologically less precisely characterized than histologically. Provisional cytological diagnosis or differential diagnosis were formulated in 112 cases. Most commonly, the distinction between neoplastic and non-neoplastic character of a lesion was not possible (especially in mesenchymal spindle-cell proliferations). In 53 cases, the cytological diagnosis could not be established. In 22 cases, the relevant lesion was diagnosed only histologically whereas the cytological picture revealed another, usually secondary tissue reaction. Cytologically incorrect diagnoses were formulated in 14 cases. 相似文献
113.
<正> 本文要对目前所出现的自动水流记录器加以讨论。这种记录器适用于田间灌溉供水量的准确测量。该设备利用了溢流水舌抛射体型(通过测流孔)与流量成正比例变化的 相似文献
114.
果实 沙棘果实由果肉(68%)、种子(23%)和果皮(7.75%)组成(Zadernowski et al.,1997).Yang和Kallio(2001)最近发现,从中国、芬兰和前苏联(FSU)等地大量选择后采集的沙棘果实中23%~28%是种子,72%~77%是柔软的果肉/果皮.沙棘果实可提取3种油:种子油、果肉油和果皮油.不同于其他植物,沙棘果实的各部分都能合成并积累脂肪.有时果肉油和果皮油没有区别,因此统称为果实油或果肉油.沙棘叶也含油,这部分内容将在稍后部分进一步说明. 相似文献
115.
116.
华南地区覆盖旱种水稻节水及其水分利用效率研究 总被引:3,自引:0,他引:3
大田试验条件下设置常规水稻(T11)、覆膜旱作水稻(T12)、覆草旱作水稻(T13)和裸地旱作水稻(T14)4个处理,研究旱作水稻的节水效率及水分利用效率。水稻本田期T11用水总量545.40 mm,显著高于各旱作处理水稻,以此为参照,T12、T13和T14节水效率分别为35.1%、22.8%和21.2%。以裸地旱作处理T14为参照,T12节水率17.7%,而T13无明显节水效果。旱作水稻的节水效果主要发生在水稻移栽后前2个月,之后无明显节水效果。各处理以籽粒产量/耗水量为基础计算的水分利用效率(WUE),T12、T13、T14和T11处理分别为1.47、1.31、1.21和1.05 g/kg,以干物质量/耗水量为基础计算的WUE各处理之间的趋势与以籽粒产量/耗水量计算的WUE基本一致。 相似文献
117.
植物根系是土壤结构以及土壤水力参数变化的重要影响要素。目前不仅缺乏定量描述“根-孔隙-土壤水力参数”相互作用的研究方法,在更大尺度上根系作用的客观表达也尚不明确,由此导致降雨入渗、径流和蒸发等流域水文过程的精细刻画与模拟预测具有很大的不确定性。基于文献检索,本文对国内外相关研究进行了回顾与梳理,量化了植物根系对土壤水力参数的改变和影响,并提出其与植被、土壤类型的响应方式,总结了植物根系动态性生长下的土壤水力参数定量表述及其预测模型进展。同时分析了在定量研究根-土复合系统中存在的问题及未来研究的发展方向,指出目前根系影响土壤水力参数的研究主要集中在小尺度控制实验方面,忽略了大尺度下土壤空间异质性及外部环境因素的干扰,强调大尺度根系作用和根系参数纳入土壤结构的重要性和实际意义,进一步与水文模型的深度耦合逐渐成为未来研究的热点。 相似文献
118.
Wu Q Lohrey L Cramer B Yuan Z Humpf HU 《Journal of agricultural and food chemistry》2011,59(23):12480-12485
Deoxynivalenol (DON) is a toxic secondary metabolite produced by molds of the Fusarium genus and is known to cause a spectrum of diseases in animals such as vomiting and gastroenteritis. It is found in cereals and cereal products as most processing techniques lead only to a partial reduction of deoxynivalenol levels. One technique with a reported relatively high impact on deoxynivaleol decomposition is extrusion cooking. In the current work, systematic studies of a range of physicochemical parameters, such as temperature, moisture, compression, residence time in the extruder, pH value, and protein content, on their impact on deoxynivalenol decomposition during extrusion cooking were performed. The analysis of deoxynivalenol was made by high-performance liquid chromatography--tandem mass spectrometry using a quick, easy, cheap, effective, rugged, and safe-based cleanup with 15-d(1)-deoxynivalenol as an internal standard. It could be shown that the reduction of deoxynivalenol levels is dependent on a set of parameters partially interacting with each other. Especially the moisture content and compression are key factors for the reduction of deoxynivalenol levels. A correlation between residence time of the mycotoxin in the extruder and deoxynivalenol degradation was also observed when screws without a compression factor were used. Generally, the reduction of deoxynivalenol levels was increased by the use of screws with a high compression factor. As known from cooking, deoxynivalenol could also be easily degraded by extrusion under alkaline conditions. Furthermore, an increase of the protein content of the starting material resulted in higher reduction rates of deoxynivalenol. 相似文献
119.
An investigation of the diffusional mobility of a bioactive compound (caffeine) within the high-solid (80.0% w/w) matrices of glucose syrup and κ-carrageenan plus glucose syrup exhibiting distinct mechanical glass transition properties is reported. The experimental temperature range was from 20 to -60 °C, and the techniques of modulated differential scanning calorimetry, small deformation dynamic oscillation in shear, and UV spectrometry were employed. Calorimetric and mechanical measurements were complementary in recording the relaxation dynamics of high-solid matrices upon controlled heating. Predictions of the reaction rate theory and the combined WLF/free volume framework were further utilized to pinpoint the glass transition temperature (T(g)) of the two matrices in the softening dispersion. Independent of composition, calorimetry yielded similar T(g) predictions for both matrices at this level of solids. Mechanical experimentation, however, was able to detect the effect of adding gelling polysaccharide to glucose syrup as an accelerated pattern of vitrification leading to a higher value of T(g). Kinetic rates of caffeine diffusion within the experimental temperature range were taken with UV spectroscopy. These demonstrated the pronounced effect of the gelling κ-carrageenan/glucose syrup mixture to retard diffusion of the bioactive compound near the mechanical T(g). Modeling of the diffusional mobility of caffeine produced activation energy and fractional free-volume estimates, which were distinct from those of the carbohydrate matrix within the glass transition region. This result emphasizes the importance of molecular interactions between macromolecular matrix and small bioactive compound in glass-related relaxation phenomena. 相似文献
120.
Han B Li C Zhang L Fang Y Feng M Li J 《Journal of agricultural and food chemistry》2011,59(18):10346-10355
Royal jelly (RJ) plays an important role in caste determination of the honeybee; the genetically same female egg develops into either a queen or worker bee depending on the time and amount of RJ fed to the larvae. RJ also has numerous health-promoting properties for humans. Gel-based and gel-free proteomics approaches and high-performance liquid chromatography-chip quadruple time-of-flight tandem mass spectrometry were applied to comprehensively investigate the protein components of RJ. Overall, 37 and 22 nonredundant proteins were identified by one-dimensional gel electrophoresis and gel-free analysis, respectively, and 19 new proteins were found by these two proteomics approaches. Major royal jelly proteins (MRJPs) were identified as the principal protein components of RJ, and proteins related to carbohydrate metabolism such as glucose oxidase, α-glucosidase precursor, and glucose dehydrogenase were also successfully identified. Importantly, the 19 newly identified proteins were mainly classified into three functional categories: oxidation-reduction (ergic53 CG6822-PA isoform A isoform 1, Sec61 CG9539-PA, and ADP/ATP translocase), protein binding (regucalcin and translationally controlled tumor protein CG4800-PA isoform 1), and lipid transport (apolipophorin-III-like protein). These new findings not only significantly increase the RJ proteome coverage but also help to provide new knowledge of RJ for honeybee biology and potential use for human health promotion. 相似文献