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991.
The fruit fly Drosophila melanogaster is an excellent model organism for studying insect reproductive biology. Although the gene expression profiles of both male and female reproductive organs have been studied in detail, their proteomic profiles and functional characteristics largely remained to be clarified. In this study, we conducted proteome mapping of the male internal reproductive organs using 2‐DE. We identified a total of 440 protein components from gels of the male reproductive organs (testis, seminal vesicle, accessory gland, ejaculatory duct, and ejaculatory bulb). A number of proteins associated with odorant/pheromone‐binding, lipid metabolism, proteolysis, and antioxidation were expressed tissue specifically in the male reproductive system. Based on our proteomic data set, we constructed reference proteome maps of the reproductive organs, which will provide valuable information toward a comprehensive understanding of Drosophila reproduction.  相似文献   
992.
黄淮平原冬小麦灌溉需水量的影响因素与不同年型特征   总被引:4,自引:0,他引:4  
以黄淮平原区80个气象站点46~54年的降水资料和10个站点100 cm深度的土壤湿度资料为基础,运用麦田水分平衡原理,分析了冬小麦灌溉需水量与冬小麦需水量、生育期降水量和土壤底墒水的关系,并就不同气候年型分析了冬小麦灌溉需水量的变化特征.结果表明:黄淮平原冬小麦灌溉需水量等值线基本呈纬向分布,自南向北逐渐增大.正常年零值线位于许昌、扶沟、柘城,鹿邑、亳州、萧县至徐州一带,此线附近冬小麦需水量和供水量基本平衡,可以不进行灌溉或进行少量灌溉;此线以北则必须进行灌溉,其灌溉量愈向北愈大,依次为60~100和100~190 mm,要分别灌1~2水和2水;此线以南,可不进行灌溉.丰水年零值线北移约0.5~1.0个纬度,全区灌溉面积和灌溉量明显减小.欠水年零值线南移约1.0~1.5个纬度,灌溉面积和灌溉量显著增大.
Abstract:
By using the last 46-54 years precipitation data from 80 meteorological stations and the 0-100 cm soil water content data at 10 stations in the Huanghuai Plain, the relationships be-tween the irrigation water requirement and water requirement by winter wheat, and between the precipitation in winter wheat growth season and the soil water content at planting time were ana-lyzed, based on the principles of farmland water balance. In the meantime, the characteristics of irrigation water requirement by winter wheat in different climatic years were studied. In the study area, the isoline of irrigation water requirement by winter wheat was basically in latitudinal distri-bution, with the requirement increased gradually from .south to north. In normal years, the zero isoline was located in Xuchang-Fugou-Zhecheng-Luyi-Bozhou-Xiaoxian-Xuzhou. Along this line, the water requirement by winter wheat was in balance with water supply, and no or less irrigation was required. However, in the north of this line, irrigation should be made, with the irrigation a-mount increased northward, being about 60-100 mm and 100-190 mm and irrigating 1-2 times or 2 times. In the south of this line, no irrigation was required. In the years of plentiful precipita-tion, the zero isoline moved northward by 0. 5-1.0 latitude, and the irrigation area and irrigation amount decreased obviously; while in the years of short precipitation, the zero isoline moved south-ward by 1.0-1.5 latitude, and the irrigation area and irrigation amount increased obviously.  相似文献   
993.
目的:为制定中国中年女性红细胞计数正常参考值的统一标准提供科学依据.方法:收集了中国331个单位用显微镜计数法测定的41003例中年女性红细胞计数正常参考值,运用相关分析和回归分析的方法,研究了其与八个地理因素的关系.结果:发现中年女性红细胞计数正常参考值与中国地理因素之间有很显著的相关关系(F=364.76,P=0.000).用逐步回归分析的方法推导出了一个回归方程:Y^=4.184+0.0002421X1-0.02921X4+0.0002582X7+0.08144X8±0.47.结论:如果知道了中国某地的地理因素,就可以用回归方程计算这个地区的红细胞计数正常参考值.依据红细胞计数正常参考值与地理因素的依赖关系,把中国分为八个区.  相似文献   
994.
Aims l-Carnitine exerts an important role by facilitating the mitochondrial transport of fatty acids, but is also a scavenger of free radicals, protecting cells from oxidative damage. Phenylketonuria (PKU), an inborn error of phenylalanine (Phe) metabolism, is currently treated with a special diet consisting of severe restriction of protein-enriched foods, therefore potentially leading to l-carnitine depletion. The aim of this study was to determine l-carnitine levels and oxidative stress parameters in blood of two groups of PKU patients, with good and poor adherence to treatment. Methods Treatment of patients consisted of a low protein diet supplemented with a synthetic amino acids formula not containing Phe, l-carnitine, and selenium. l-Carnitine concentrations and the oxidative stress parameters thiobarbituric acid reactive species (TBARS) and total antioxidant reactivity (TAR) were measured in blood of the two groups of treated PKU patients and controls. Results We verified a significant decrease of serum l-carnitine levels in patients who strictly adhered to the diet, as compared to controls and patients who did not comply with the diet. Furthermore, TBARS measurement was significantly increased and TAR was significantly reduced in both groups of phenylketonuric patients relatively to controls. We also found a significant negative correlation between TBARS and l-carnitine levels and a significant positive correlation between TAR and l-carnitine levels in well-treated PKU patients. Conclusions Our results suggest that l-carnitine should be measured in plasma of treated PKU patients, and when a decrease of this endogenous component is detected in plasma, supplementation should be considered as an adjuvant therapy.  相似文献   
995.
The US Pharmacopeial Convention has been evaluating its performance verification tests (PVT) for several years. These tests help ensure the integrity of the US Pharmacopeia performance test when a dissolution procedure, as described in General Chapter Dissolution <711>, is relied upon to test a nonsolution orally administered dosage form. One result of the evaluation is a change in the PVT criterion from one based on individual tablet results to one based on the mean and variability of a set of tablets. This paper describes the new PVT and its criterion and how its acceptance limits are derived from results of a collaborative study, explains a two-stage option for the test, and presents operating characteristics.  相似文献   
996.
Cross-sectional covariate-related reference ranges are widelyused in clinical medicine to put individual observations inthe context of population values. Usually, such reference rangesare created from data sets of independent observations. If multiplemeasurements per individual are available, then ignoring thewithin-person correlation between repeats will lead to overestimationof centile precision. Furthermore, if abnormal measurementshave triggered more frequent assessment, the data set will bebiased thus producing biased centiles. Where multiple measuresper individual exist, the methods commonly used are either randomlyor systematically to select one observation per individual orto model individual trajectories and combine these. The firstof these approaches may result in discarding a large proportionof the available data and may itself cause bias and the latterrequires the form of the changes within individuals to be characterized.We have developed an approach to the modeling of the median,spread, and skew across individuals using maximum likelihood,which can incorporate correlations between dependent observations.Heavily biased data sets are simulated to illustrate how themethodology can eliminate the biases inherent in the data collectionprocess and produce valid centiles plus estimates of the within-personcorrelations. The "select one per individual" approach is shownto be liable to bias and to produce less precise centiles. Werecommend that the maximum likelihood method incorporating correlationsbe used with existing data sets. Furthermore, this is a potentiallymore efficient approach to be considered when planning the futurecollection of data solely for the purposes of creating cross-sectionalcovariate-related reference ranges.  相似文献   
997.
Nesidiocoris tenuis (Reuter) (Heteroptera: Miridae) is common in vegetable crops of the Mediterranean area, with an increasing worldwide range of geographical distribution. This omnivore is a reputed predator of small arthropod pests, but also produces injuries on vegetative and reproductive plant parts. The aim was to estimate density thresholds based on N. tenuis and whitefly abundance for the management of N. tenuis in tomato crops. The assay was carried out in mesh-walled and plastic greenhouses in southern Spain during 2004 and 2007. The natural population dynamics of N. tenuis and whitefly were monitored, and impact on yield quantified. The economic injury level and intervention threshold were predicted based on the zoophytophagous response of N. tenuis and the yield compensation of tomato plants. The proportion of aborted flowers on the tomato plants was related directly to the abundance of N. tenuis and inversely to the interaction between the number of N. tenuis and the number of whitefly immatures. Over-compensation of fruit weight was predicted for flower abortion rates due to N. tenuis lower than 0.171. No yield reduction is expected for values <0.65 N. tenuis per leaf, independent of the whitefly abundance, nor for up to 5 N. tenuis and >26 whitefly immatures per leaf. For intermediate N. tenuis levels, the outcome depends on the prey density. The probability of N. tenuis producing yield loss in tomato crops increases at N. tenuis:whitefly ratios >0.168. Yield reduction is expected after N. tenuis population peaks, when whitefly numbers have been reduced.  相似文献   
998.
Selection is recognized to operate on multiple levels. In disease organisms, selection among hosts is thought to provide an important counterbalance to selection for faster growth within hosts. We performed three experiments, each selecting for a divergence in group size in the entomopathogenic nematode, Steinernema carpocapsae. These nematodes infect and kill insect larvae, reproduce inside the host carcass, and emerge as infective juveniles. We imposed selection on group size by selecting among hosts for either high or low numbers of emerging nematodes. Our goal was to determine whether this trait could respond to selection at the group level, and if so, to examine what other traits would evolve as correlated responses. One of the three experiments showed a significant response to group selection. In that experiment, the high-selected treatment consistently produced more emerging nematodes per host than the low-selected treatment. In addition, nematodes were larger and they emerged later from hosts in the low-selected lines. Despite small effective population sizes, the effects of inbreeding were small in this experiment. Thus, selection among hosts can be effective, leading to both a direct evolutionary response at the population level, as well as to correlated responses in populational and individual traits.  相似文献   
999.
The association seen in epidemiological studies between childhood leukemia and magnetic field strength in the child's home has been very important in influencing reviews of international groups and standard setting organizations. This association is usually based on the results of two published pooled analyses, which use definitions of exposure that differ from those of some the original studies. However, the results and conclusions of the pooled analyses differ from those of the three largest recent studies, which have the most sophisticated methodology and together account for the majority of the exposed cases at high exposure levels in the pooled analyses. These recent studies, using the exposure methods and the cut-off levels set a priori, each concluded that there was little evidence of any association. The pooled analyses, using different exposure measures and different cut-offs, conclude that an association exists at high exposure levels. It is not clear if the results of the pooled analysis are more valid than those of the recent major studies, although this has been often assumed in influential reviews.  相似文献   
1000.
A study of the interaction between mobile phone antennas and a human head in the presence of different types of metallic objects, attached and pierced to the compressed ear, is presented in this article. Computed and measured results have been performed by considering a quasi-half-wavelength dipole as the radiating source and measurements with the DASY4 dosimetric assessment system. Two different human head models have been implemented: a homogeneously shaped sphere and a three-level head model with four different kinds of tissue. Antenna input impedance, reflection coefficient, radiation patterns, SAR distribution, absorbed power, and peak SAR values have been computed and measured for diverse scenarios, electromagnetic simulators, and organs. Despite the measuring accuracy limitations of the study, both simulated and measured results suggest that special attention has to be paid to peak SAR averaged values when wearing metallic objects close to the radiation source, since some increment of peak SAR averaged values is expected.  相似文献   
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