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101.
102.
Although mungbean (Vigna radiata (L.) Wilczek) is commonly used as human food; the genomic resources of this species available in databases are limited. This
study aims to develop expressed sequence tag (EST) resources for mungbean genes informative to early seedling development
and chilling response. Two mungbean varieties that differ in disease resistance were found to also differ in their susceptibility
to chilling temperatures. A total of 1,198 ESTs were obtained from one cDNA library and four PCR-select cDNA subtraction libraries;
among these 523 were clustered into 136 contigs and 675 were singletons. The 811 non-redundant uniESTs were compared to GenBank
using the Basic Local Alignment Search Tool (BLAST) and WU-BLAST algorithms, of these only 489 uniESTs had significant sequence
homology, which may be involved in resuming the metabolic activity of seedlings, switching on photomorphogenesis, fuelling
photosynthesis and/or initiating the unique developmental programs. Their encoded proteins may associate with regulatory proteins
to trigger a direct stress response or participate in acclimation to environmental stressors. The uniEST platform reported
will enrich the genomic resources of mungbean for functional genomic research on seedling development and chilling response
of tropical crops and provide targets for improving the chilling tolerance of the tropical crops.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
103.
PurposeOptimization studies in digital mammography aid to assure the image quality and radiological protection of the patient. The aim of this work is to test effectiveness and applicability of a method based on a Figure of Merit (FOM = (IQFinv)2/AGD) to improve all the exposure parameters (Target/Filter combination, kVp and mAs) in order to improve the image acquisition technique that will provide the best compromise between image quality and the average glandular dose (AGD).MethodsA contrast-detail analysis, employing the test object CDMAM, was carried out for the digital mammography unit manufactured by Lorad Hologic – model Selenia. We simulated two breast thicknesses using phantoms and a Figure of Merit as optimization tool, which includes an indicator of image quality, the IQFinv and the average glandular dose. Images of the ACR and TORMAM phantoms were obtained with both, automatic and optimized exposure parameters. In order to compare the image quality, the SNR (Signal to Noise Ratio) was measured in each image.ResultsIn the two phantoms, for both 4.5 and 7.5 cm thicknesses, the AGDs obtained with the optimized parameters show a reduction. In addition, the images obtained with the optimized exposure parameters, had the same or a better image quality when compared to the images obtained using the automatic mode.ConclusionsThe proposed optimization methodology proved to be an effective tool to improve the digital mammography unit, due to the use of objective metrics for evaluation and validation of the results. 相似文献
104.
Color is one of the factors used in quality estimation in many agricultural and food products. Currently, the evaluation of color depends on judgments made by human experts. These are subjective and inevitably affected by physical, physiological and environmental conditions. Suitable instrumental is required to provide objectivity and coherence to color measurements and quantitative expressions. It would be very useful to have tools that allow both practical and precise approaches to chromatic evaluation of products for human consumption. This work suggests a methodology which might contribute to solve that constraint and the analysis of environmental influences on this character in two consecutive wheat growing seasons. This research used 18 cultivars, which were sampled in two crop growth stages. On the first part of this study, a spectrophotometer and a digital camera were used for the analysis of color at the phenological state of tillering. Data analysis showed a correlation between both study methodologies, which would make more practical the work of breeders during data collection. The second part of the study of the genotype-environment interaction (GEI) continued using only a digital camera. The phenological state of tillering did not evidence a marked GEI. On the other hand, an appreciable GEI was found at physiological ripeness. 相似文献
105.
Canopy structure in a temperate old-growth evergreen forest analyzed by using aerial photographs 总被引:2,自引:0,他引:2
We used aerial photographs to create a digital elevation model of the canopy surface of a 10-ha study area in a temperate old-growth evergreen forest. A topographic map of the ground surface in a 4-ha permanent plot within the study area was also drawn from ground measurements. The difference between the two elevation values (i.e., canopy surface – ground surface) at each point in a 5-m grid was considered to be the canopy height, and a canopy height profile was constructed from these data. The canopy structure in the 4-ha plot that was estimated in this way was compared with that obtained by two ground observation methods, i.e., the canopy (vegetation) height profile method and the canopy coverage census method. Large gaps were adequately detected by the aerial photograph method, but small gaps were less often detected. Gap size distribution obtained by the aerial photograph method was similar to that observed on the ground, and was a function of gap depth. This study indicates that if a detailed topographic map can be made, the canopy height profile derived from aerial photography can be effective in analyzing the canopy structure of evergreen forests, such as tropical rain forests, over large areas. 相似文献
106.
107.
摘要 目的:探讨数字减影血管造影(DSA)引导下肝动脉化疗栓塞(TACE)对肝癌患者肝功能、细胞免疫功能及肿瘤标志物的影响。方法:随机选取2021年1月~2022年1月来我院就诊的行DSA引导下TACE化疗的肝癌患者50例为研究组,另随机选取同期行常规治疗的肝癌患者50例为对照组,对比两组临床总有效率、肝功能、细胞免疫功能及肿瘤标志物和不良反应情况。结果:研究组的临床总有效率为56.00%(28/50)高于对照组的34.00%(17/50),差异有统计学意义(P<0.05)。两组治疗结束后谷草转氨酶(AST)和谷丙转氨酶(ALT)升高,但研究组低于对照组(P<0.05)。两组治疗结束后CD8+升高,但研究组低于对照组(P<0.05);CD4+、CD4+/CD8+、CD3+均下降,但研究组高于对照组(P<0.05)。两组治疗结束后甲胎蛋白(AFP)、糖链抗原(CA)242、CA724、磷脂酰肌醇蛋白聚糖-3(GPC3)下降,且研究组低于对照组(P<0.05)。对照组(30.00%)、研究组(24.00%)的不良反应发生率组间对比无差异(P>0.05)。结论:DSA引导下TACE化疗治疗肝癌患者,疗效可靠,可有效阻止疾病进展,同时减轻化疗所致的肝损伤和细胞免疫功能损伤。 相似文献
108.
Seiji Ito Noriko Mochizuki-Oda Kunio Hori Kazuho Ozaki Atsuo Miyakawa Manabu Negishi 《Journal of neurochemistry》1991,56(2):531-540
We recently reported that prostaglandin E2 (PGE2) stimulates phosphoinositide metabolism accompanied by an increase in intracellular free Ca2+ concentration ([Ca2+]i) in cultured bovine adrenal chromaffin cells. In the present study, temporal and spatial changes in [Ca2+]i induced by PGE2 in fura-2-loaded individual cells were investigated by digital image microscopy and were compared with those induced by nicotine and histamine. Image analysis of single cells revealed that responses to PGE2 showed asynchrony with the onset of [Ca2+]i changes. After a lag time of 10-30 s, PGE2-induced [Ca2+]i changes took a similar prolonged time course in almost all cells: a rapid rise followed by a slower decline to the basal level over 5 min. Few cells exhibited oscillations in [Ca2+]i. In contrast, nicotine and histamine induced rapid and transient [Ca2+]i changes, and these [Ca2+]i changes were characteristic of each stimulant. Whereas pretreatment of the cells with pertussis toxin (100 ng/ml, 6 h) did not block the response to any of these stimulants, treatment with 12-O-tetradecanoylphorbol 13-acetate (100 nM, 10 min) completely abolished [Ca2+]i changes elicited by PGE2 and histamine. In a Ca2(+)-free medium containing 3 mM EGTA, or in medium to which La3+ was added, the [Ca2+]i response to nicotine disappeared, but that to histamine was not affected significantly. Under the same conditions, the percentage of the cells that responded to PGE2 was reduced to 37% and the prolonged [Ca2+]i changes induced by PGE2 became transient in responding cells, suggesting that the maintained [Ca2+]i increase seen in normal medium is the result of a PGE2-stimulated entry of extracellular Ca2+. Whereas the organic Ca2(+)-channel blocker nicardipine inhibited [Ca2+]i changes by all stimulants at 10 microM, these [Ca2+]i changes were not affected by any of the organic Ca2(+)-channel blockers, i.e., verapamil, diltiazem, nifedipine, and nicardipine, at 1 microM, a concentration high enough to inhibit voltage-sensitive Ca2+ channels. These results demonstrate that PGE2 may promote Ca2+ entry with concomitant release of Ca2+ from intracellular stores and that the mechanism(s) triggered by PGE2 is apparently different from that by histamine or nicotine. 相似文献
109.
110.
Robert A. Boroffice 《American journal of physical anthropology》1978,49(2):167-169
Eight hundred Nigerians (400 males and 400 females) were screened for the analysis of digital dermatoglyphic patterns. The frequency distribution of the patterns are 52.09%, 27.67%, 19.20% and 1.13% for ulnar loops, whorls, arches and radial loops respectively. Except for arches, the males have more of the patterns than females. The pattern intensity indices for males and females are 11.2 and 9.9 respectively. Bilateral symmetry is similar in both sexes and the percent distribution is as high as 81.5% and 84% on digit V in males and females respectively. 相似文献