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61.
Akihisa HATA Masaaki OCHI Kayo FURUMOTO Noboru FUJITANI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(10):1422
Lactate dehydrogenase (LDH) in blood is measured using the Japanese Society of Clinical Chemistry (JSCC) method in Japan and the International Federation of Clinical Chemistry (IFCC) method in other countries. In human clinical practice, the IFCC method replaced the JSCC method due to international standardization. Moreover, veterinary LDH measurement will also eventually shift to the IFCC method. However, the relationship between the IFCC and JSCC methods for LDH in various animals and whether they can be equated or not have not yet been investigated. This study aimed to present the changes in measurements in canines and felines after switching to the IFCC method. The plasma LDH activity of canines (N=177) and felines (N=115), who visited a secondary care veterinary clinic, was measured using the JSCC and IFCC methods. The IFCC/JSCC ratio was <1.0 in 85% of canines and 88% of felines, indicating that the IFCC method tended to show lower values than the JSCC method, presumably because LDH5 is dominant among the LDH isozymes in canines and felines. The increase in the systematic errors of both assays was in the high value range, with some samples exceeding the error tolerance from near the upper end of the reference range. When switching to the IFCC method for LDH measurement in canines and felines, each institution should consider whether the reference range and clinical diagnostic values established by the JSCC method are appropriate for continued use. 相似文献
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64.
Dispersion and migration of fine particles in two palygorskite‐containing soils of the Jordan Valley
Migration of different mineral particles within columns of soil‐sand mixtures containing 10 or 20 mass % of soil was investigated by establishing differences in the mineral suite between the ”︁bulk clay” and the ”︁mobile fine material” fractions. The ”︁bulk clay” fractions of all soils contained smectite, palygorskite, kaolinite, quartz, feldspar, and calcite. The soils were saturated with sodium by leaching with NaCl solution, and then leached with distilled water. Clay dispersion and particle migration occurred in the columns. Values of SAR (sodium adsorption ratio) of the effluent decreased with time due to carbonate dissolution. At a certain SAR value, the clays apparently formed aggregates, and as a consequence particle migration stopped in the column. In addition to clay‐sized particles (< 2 μm), very‐fine‐silt‐sized particles (2— 5 μm) were able to migrate in the soil‐sand mixtures, too, and to some extent fine‐silt‐sized particles (5—10 μm) as well. Average size of mobile particles decreases with increase of soil content in the soil‐sand mixtures. The mineralogical composition of the ”︁mobile fine material” changed during the experiment. At the beginning of the experiment, the ”︁mobile fine material” was enriched in the non‐phyllosilicates (especially in calcite, and in some cases in quartz, feldspar and dolomite) and contained low concentrations of phyllosilicates (smectite, palygorskite and kaolinite). At the end of the experiment, the proportion of non‐phyllosilicates decreased, and as a consequence, the proportion of phyllosilicates increased. Among the non‐phyllosilicates, calcite was the most mobile mineral. Among the phyllosilicates, palygorskite was preferentially mobilized in topsoil horizons. In subsoil horizons, on the other hand, kaolinite was preferentially mobilized. This difference was explained by the different nature of carbonates in the topsoil and subsoil horizons. Palygorskite is preferentially occluded within the soil carbonates of lacustrine origin over smectite and kaolinite. These carbonates are present mainly in the subsoil horizons. As a consequence, the presence of these carbonates in the subsoil horizons decreases the migration of mainly palygorskite. 相似文献
65.
采用现存生殖分配(Standing Reproduction Allocation)的方法研究甘南地区歪头菜(Vicia unijuga)生物量生殖分配。结果表明,不同生长年限植株在整个生长季中,各构件生物量占总生物量的比例随着季节变化表现为营养分配比重不断减少,生殖分配比重不断增加,但营养生物量分配比例占绝对优势,而在蕾期和花期用于有性生殖的生物量(蕾、花生物量)分配比例仅在10%左右;多年生歪头菜种群幼龄时期植株生殖生物量分配仍然随着生长年限的增加而增加,但生殖产量的生物量分配却表现出2年龄5年龄4年龄;2年龄植株蕾-花生物量转换比例和花-荚生物量转换比例分别为1∶1.17和1∶1.36,5年龄植株的分别为1∶0.94和1∶1.31,说明2年龄植株比5年龄植株有较高的生殖利用率,而5年龄植株落花、落荚现象明显。以上结果揭示出,植株对有性繁殖的小比例投资以及生殖转换中产生的生殖损失可能是导致该地区歪头菜种群有性繁殖体种子产量低的重要原因,而影响这一原因的因素可能是生长季过程中的环境干扰和养分竞争等问题。 相似文献
66.
德系安哥拉兔不仅以产毛量高、毛质好而著称,而且有生长迅速、体成熟早、体型大的特点。六月龄时已达成年体重的87.37%。母兔的初配可在此时进行,公兔可延迟一个月配种。四月龄与六月龄体重和成年体重的相关系数分别为0.505与0.508,这为德系安哥拉兔体重的早期选择提供了有利时机。 相似文献
67.
The origin,evolution, cultivation,dissemination, and diversification of Asian and African rices 总被引:28,自引:0,他引:28
Te-Tzu Chang 《Euphytica》1976,25(1):425-441
Summary Available evidences drawn from biosystematics, evolutionary biology, biogeography, archaeology, history, anthropology, paleo-geology and paleo-meteorology are pooled to reconstruct the series of events that led to the cosmopolitan cultivation of the Asian cultivated rice (O. sativa) and the regionalized planting of the African cultigen (O. glaberrima) in West Africa. The genus Oryza originated in the Gondwanaland continents and, following the fracture of the supercontinent, became widely distributed in the humid tropics of Africa, South America, South and Southeast Asia, and Oceania. The two cultivated species have had a common progenitor in the distant past. Parallel and independent evolutionary processes occurred in Africa and in Asia, following the sequence of: wild perennialwild annualcultivated annual. The weed races also contributed to the differentiation of the cultivated annuals. The corresponding members of the above series are O. longistaminata
Chev. et Roehr., O. barthii
A. Chev., O. glaberrima
Steud., and the stapfii forms of O. glaberrima in Africa; O. rufipogon
Griff., O. nivara
Sharma et Shastry, O. sativa L., and the spontanea forms of O. sativa in Asia.The differentiation and diversification of the annuals in South Asia were accelerated by marked climatic changes following the last glacial age, dispersal of plants over latitude or altitude, human selection, and manipulation of the cultural environment.Cultivation of rice began in many parts of South and Southeast Asia, probably first in Ancient India. Cultural techniques such as puddling and transplanting were first developed in north and central China and later transmitted to Southeast Asia. Wetland culture preceded dryland culture in China, but in hilly areas of Southeast Asia, dryland cultivation is older than lowland culture. The planting method progressed from shifting cultivation to direct sowing in permanent fields, then to transplanting in bunded fields.Widespread dispersal of the Asian cultigen led to the formation of three eco-geographic races (Indica. Sinica or Japonica, and Javanica) and distinct cultural types in monsoon Asia (upland, lowland, and deep water). Varietal types changed readily within the span of a millenium, largely due to cultivators' preferences, socio-religious traditions, and population pressure. Genetic differentiation developed parallel to the ecologic diversification process.The African cultigen developed later than the Asian cultigen and has undergone less diversification. The wild races in South America and Oceania retain their primitive features mainly due to lack of cultivation pressure or dispersal.Both the African and Asian rices are still undergoing evolutionary changes at habitats where the wild, weed, and cultivated races co-exist. 相似文献
68.
Summary A germ plasm collection of safflower, Carthamus tinctorius L., with about 900 lines from over twenty countries was evaluated in Utah, USA for head width and outer involucral bracts (OIB) dimensions, traits affected by both human and natural selection. The regional germ plasm pools contained considerable variability for these traits. Plants bearing short or long as well as narrow or wide OIB were well adapted. Geographical clines were detected for the means of OIB dimensions, indicating possible gene flow. The correlations of the OIB dimensions with yield, yield components, oil content and growing period were not instructive and at times very inconsistent. Primary head diameter varied considerably within the regional gene pools. Its correlations with yield/plant, number of heads/plant, seed weight and oil content were inconsistent. Capitulum width was positively and significantly correlated with the number of seeds per head. Head diameter, however, can vary considerably without affecting seed yield per unit area. 相似文献
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