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1.
SUMMARY: Preference for artificial burrows by the endangered Japanese crayfish species Cambaroides japonicus was studied to improve its cultivation. The occupation of artificial burrows, which were made from straight polyvinyl chloride pipes of different internal diameters ( Y , mm), by crayfishes of different total lengths ( X , mm) was significantly ( P < 0.001, n = 56) described by a linear regression: Y = 0.49 X + 3.42 (19.0 ≤ X ≤ 70.2). Among burrows of different lengths [crayfish total length (TL) × 1, × 2, × 3, and × 4], crayfishes significantly preferred burrows that were greater than TL × 3 ( P < 0.001, n = 588).  相似文献   
2.
Southeast Asia is a region of high biodiversity, containing species of plants and animals that are yet to be discovered. In this region, bats of the subfamily Kerivoulinae are widespread and diverse with six species recorded in Vietnam. However, the taxonomy of the Kerivoulinae in Asia is complicated. In our study, we used diagnostic characters and multivariate analysis to determine morphological differences between the genera Kerivoula and Phoniscus. We showed that the two genera are distinguishable by the size of second upper incisors, the shape of skull, nasal sinus, canines, second upper and lower premolars. In addition, the two genera can be osteometrically separated by measurements of the braincase height, interorbital width and shape of anterior palatal emargination. Our data clearly revealed the morphological variations in the skull shape of Kerivoula hardwickii in Vietnam. This suggests a possible separation into three morphotypes, representing cryptic species supported by statistical differences with wide variation in skull shape, size and teeth. These results demonstrated Kerivoula hardwickii can be separated three subspecies, and the result will serve as the basis for the future assessment and classification of this group in Southeast Asia.  相似文献   
3.
Skulls of the red-cheeked squirrel (Dremomys rufigenis) from various geographical locations: Malaysia (peninsular area), Vietnam (south district)-Laos, and Thailand (north district) were osteometrically examined. The skull size of the squirrels in the southern (Malaysia) population was fundamentally larger than that in the northern (Vietnam, Laos and Thailand) populations. The proportion indices indicated that the splanchnocranium was relatively longer in the Malaysia population, and that the interorbital space was narrower in Vietnam-Laos, and Thailand populations. We suggest that the long nose and laterally-oriented orbits in the skull may be better adapted for terrestrial-insectivorous life in the Malaysia population and the binocular sense facilitated by rostrally-oriented eyes contributes to the arboreal-fruit eating behavior in the two northern populations. The Malaysia population was clearly distinguished from the other populations by the principal component analysis. We suggest that the geographical barrier of the Isthmus of Kra influences the morphological variation of the skull among the squirrel populations.  相似文献   
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Morphiceptin (Tyr-Pro-Phe-Pro-NH(2)), tetrapeptide, was synthesized using dipeptidyl aminopeptidase IV (DP IV, EC 3.4.14.5) derived from Aspergillus oryzae RIB 915 as a catalyst. Tyr-Pro-OEt was incubated with Phe-Pro-NH(2) in the presence of DP IV under various conditions of temperature, concentrations of ethylene glycol, pH, reaction time, and others. Morphiceptin was obtained at 40% yield under the optimal reaction conditions: substrate, 4 mM Tyr-Pro-OEt.HCl and 20 mM Phe-Pro-NH(2).HCl; enzyme, DP IV, 0.275 nkat; solvent, 60% ethylene glycol containing 20 mM phosphate buffer at pH 7.0; amine, 4.2 mM diisopropylamine at 4 degrees C for 24 h. Amino group protection was unnecessary for synthesis of morphiceptin by DP IV.  相似文献   
7.
Reservoirs have the potential to block the gene flow of stream macroinvertebrates along a channel, which takes place via larval drift and adult flight, resulting in genetic differentiation above and below the reservoirs. Gene flow across the reservoirs may be strongly obstructed if the area of standing water is larger. Using random amplified polymorphic DNA markers, we investigated the genetic structure of Stenopsyche marmorata (Stenopsychidae: Trichoptera) populations found above and below the reservoirs, and the reference stream of six reservoirs with small to large water surface area ranging from 0.12 km2 to 6.00 km2. As a result, the two largest reservoirs with a standing water area larger than 3.27 km2 showed significant differences in pairwise θ between fragmented and reference streams, whereas the other four reservoirs with a standing water area smaller than 1.64 km2 showed insignificant differences. The genetic differentiations in the two largest reservoirs did not result in the reduction of genetic diversities in the fragments. Based on the significant correlation between relative population size and mean expected heterozygosity, we concluded that local genetic diversities were constrained in smaller populations due to the effect of genetic drift.  相似文献   
8.
为实现仓储粮储量在线实时监测,该研究开发了一种基于三维激光扫描技术的粮食储量在线监测系统。采用自主研制的倒置式粮仓专用型三维激光扫描仪对储粮进行扫描,通过上位机通讯、采集点云数据并控制扫描仪的工作过程,应用粮食体积计算软件实时计算储粮体积和数量,从而解决了仓储粮储量快速高精度监测的问题。使用该系统在中储粮某直属库进行系统验证试验,结果表明,测量得到的粮食体积满足最大误差不超过1%的技术指标,且经过多次试验检验,系统具有较好的稳定性、测量精度高、操作简便等优点,能够满足仓储粮储量监测的要求。该研究为实现仓储粮储量的快速实时在线监测提供了有效的方法。  相似文献   
9.
In order to apply for reducing graft versus host disease in allogeneic stem cell transplantation, the study concerning the induction of specific T cell anergy was designed. Normal allogeneic lymphocytes, which were co-cultured with IL-10-treated immature dendritic cells in the first mixed leukocyte culture (MLC), were cultured with mature dendritic cells of the same origin as IL-10-treated immature dendritic cells in the second MLC. By co-culturing with IL-10-treated immature dendritic cells, the response of normal lymphocytes to mature dendritic cells cultured from the same individual as that of IL-10-treated dendritic cells was markedly reduced, compared with the lymphocytes cultured with non-treated dendritic cells or IL-10-treated dendritic cells from a third party individual. The present study demonstrated that antigen specific T cell anergy was generated by priming allogeneic lymphocytes with IL-10-treated immature dendritic cells. These data suggested the applicability of IL-10-treated recipient dendritic cells for the induction of recipient cell-specific donor T cell anergy in donor graft.  相似文献   
10.
The distribution and diameter of the pores of epithelial basement membrane in the intestinal villi and the lymph nodules of ileal Peyer's patches were investigated in the rat small intestine by scanning electron microscopy after the removal of the overlying epithelial cells with OsO(4) maceration. In the duodenum, jejunum and ileum, the pores were mainly distributed at the upper three fourths of the villi, but were scarce around the top of the villi. The diameter of some of the pores in the upper three fourths of the villi was larger than that of those in the lower portion. The protrusion of lymphocytes and the cytoplasmic processes of macrophages were also seen at the orifices of the pores. In ileal Peyer's patches, in contrast, pores were densely distributed in the lower one third of the follicle-associated epithelium (FAE) where M cells were mainly seen. Furthermore, these pores were larger than those found in the upper two thirds. Lymphocytes or cytoplasmic processes of macrophages were frequently seen in the lower one third of FAE. These results suggest that the pores at the basement membrane correspond to the passage of the immunocompetent cells which are in contact with M cells or villous columnar epithelial cells and that the abundance of pores is a sign of aggressive interaction between the particular epithelial cells and the immunocompetent cells at the upper three fourths of intestinal villi and the lower one third of FAE in the rat small intestine.  相似文献   
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