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141.
A biosemiotic view of living things is presented that supersedes the mechanistic view of life prevalent in biology today. Living things are active agents with autonomous subjectivity, whose structure is triadic, consisting of the individual organism, its Umwelt and the society. Sociality inheres in every living thing since the very origin of life on the earth. The temporality of living things is guided by the purpose to live, which works as the semantic boundary condition for the processes of embodiment of the subjectivity. Freedom at the molecular and cellular levels allows autonomy and spontaneity to emerge even in single cell organisms, and the presence of the dimension of mind in every living thing is deduced. Living things transcend their individualness, as they live in historically formed higher order structure consisting of the lineage-species and the society. They also transcend materiality, having the dimension of mind.  相似文献   
142.
A new autosomal recessive genetic condition, the SPOAN syndrome (an acronym for spastic paraplegia, optic atrophy and neuropathy syndrome), was recently discovered in an isolated region of the State of Rio Grande do Norte in Northeast Brazil, in a population that was identified by the IBGE (Brazilian Institute of Geography and Statistics) as belonging to the Brazilian communities with the highest rates of "deficiencies" (Neri, 2003), a term used to describe diseases, malformations, and handicaps in general. This prompted us to conduct a study of consanguinity levels in five of its municipal districts by directly interviewing their inhabitants. Information on 7,639 couples (corresponding to about 40% of the whole population of the studied districts) was obtained. The research disclosed the existence of very high frequencies of consanguineous marriages, which varied from about 9% to 32%, suggesting the presence of a direct association between genetic diseases such as the SPOAN syndrome, genetic drift and inbreeding levels. This fact calls for the introduction of educational programs for the local populations, as well as for further studies aiming to identify and characterize other genetic conditions. Epidemiological strategies developed to collect inbreeding data, with the collaboration of health systems available in the region, might be very successful in the prospecting of genetic disorders.  相似文献   
143.
在大田栽培条件下,分别在长江流域下游棉区(江苏南京)和黄河流域黄淮棉区(河南安阳)设置棉花氮素水平试验,定量研究氮素水平对花后棉株生物量、氮素累积特征及氮素累积利用率动态变化的影响,结果表明:棉株总生物量和氮素累积量随花后棉株生育进程的动态变化符合S型曲线,安阳、南京试点分别以360kg.hm-2、240kg.hm-2氮素水平的总生物量、氮素累积最多,其动态累积模型的特征参数值最为协调,皮棉产量最高。因此,可以通过改变施肥量来调节初花后棉株生长特征值,从而获得高产。棉株氮素累积利用率随初花后棉花生育进程的推进,呈现为不规则的S型曲线变化趋势,计算两试点的氮素累积利用率、瞬时利用率,安阳试点以360 kg.hm-2的施氮水平为最优,南京以240 kg.hm-2最高;施肥过多不仅利用率低,而且易造成营养器官比例加大,棉株虽可获得较大的干物质和氮素累积,但不能适时向生殖器官转移,皮棉产量降低。  相似文献   
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A number of recent genome-wide association (GWA) studies have identified several novel genetic determinants of plasma lipid and lipoprotein concentrations in European populations. However, it is still unclear whether these loci identified in Caucasian GWA studies also exert the same effect on lipid and lipoprotein concentrations in a Chinese population. We genotyped 10 single-nucleotide polymorphisms (SNPs) in nine loci in a Chinese Han population sample (n = 4,192) and assessed the associations of these SNPs with metabolic traits, using linear regression adjusted for age, gender, diabetes status, and body mass index. Three variants (rs12654264, P ~ 1.7 × 10(-6); rs3764261, P ~ 7.1 × 10(-7); and rs4420638, P ~ 1.1 × 10(-3)) showed strong evidence for association with total cholesterol; four variants (rs780094, P ~ 1.8 × 10(-11); rs17145738, P ~ 5.0 × 10(-7); rs326, P ~ 2.3 × 10(-6); and rs439401, P ~ 2.2 × 10(-5)) showed strong evidence for association with triglycerides, four variants (rs17145738, P ~ 1.9 × 10(-4); rs326, P ~ 9.7 × 10(-4); rs1800588, P ~ 1.5 × 10(-7); and rs3764261, P ~ 4.3 × 10(-14)) showed strong evidence for association with HDL-cholesterol (HDL-C), two variants (rs12654264, P ~ 2.3 × 10(-5); and rs4420638, P ~ 3.6 × 10(-4)) showed strong evidence for association with LDL-C, and four variants (rs326, P ~ 2.8 × 10(-3); rs1800588, P ~ 6.1 × 10(-4); rs3764261, P ~ 2.0 × 10(-3); and rs4420638, P ~ 9.4 × 10(-5)) showed strong evidence for association with total cholesterol-HDL-C-related ratio. These SNPs generated strong combined effects on lipid traits and dyslipidemia. Our findings indicate that the variants that associated with metabolic traits in Europeans may also play a role in a Chinese Han population.  相似文献   
147.
The aim of this study was to investigate whether fatty acid (FA) profile, oxidative stability of lipids and other meat quality traits differed between high (HW: 1.8 to 2.2 kg) and low (LW: 0.8 to 1.2 kg) birth weight piglets. Forty new-born male pigs (n=20 HW, n=20 LW) were reared in separate pens until the finishing period, when they were slaughtered at 150 days of age, and pH and temperature were measured in the carcass. Afterwards, the Longissimus dorsi muscle was excised from the carcass, and samples were collected for subsequent meat quality analyses (thaw loss, cooking loss, shear force, chemical analysis and sensory analysis for tenderness). Birth weight had minor impacts on meat quality traits, which were limited to higher shear force in the LW group (P<0.01). Chemical components (moisture, protein, fat, ash), cholesterol levels and lipid oxidation (thiobarbituric acid-reactive substances) were not affected by birth weight (P>0.05). FA profile and the amount of saturated, monounsaturated and polyunsaturated fatty acids were similar, but HW pigs had higher atherogenic index than their LW counterparts (P<0.01). Notwithstanding the higher shear force presented by the lower birth weight pigs, in the sensory test, the panelists did not detect any differences in the tenderness of pork from HW and LW animals. Therefore, our results suggest that low birth weight has minimal impact on meat quality.  相似文献   
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目的:探讨醒脑静对颅脑损伤大鼠的保护作用及其机制。方法:健康雄性成年SD大鼠63只,随机分为3组(n=21):假手术组、模型组、醒脑静组。模型组与醒脑静组均采用自由落体撞击伤方法制作创伤性脑损伤模型,假手术组仅行开颅术,不造成脑损伤。醒脑静组盆大鼠造模后10min内经尾静脉注射醒脑静注射液10ml/(kg·d),模型组与假手术组则经尾静脉注射等量0.9%氯化钠溶液,三组均连续给药7d。给药第7天比较各组大鼠血清中S-100B蛋白和神经特异性烯醇化酶(NSE)水平,脑组织含水量,检测血清中超氧化物歧化酶(SOD)、丙二醛(MDA)和谷胱甘肽过氧化物酶(GSH—Px)含量,并对各组大鼠进行神经功能缺损评分。结果:与假手术组比较,醒脑静组和模型组均有明显的神经缺损,脑组织含水量、MDA、S-100B蛋白和NSE水平明显升高,SOD、GSH-Px含量明显降低;醒脑静组与模型组比较,醒脑静组神经缺损程度及脑含水量显著低于模型组,血清中MDA和NSE水平明显低于模型组,SOD、GSH-Px活性明显高于模型组。结论:醒脑静注射液对大鼠颅脑损伤具有保护作用,其作用机制可能与减轻颅脑损伤后脑水肿及抑制氧自由基反应、保护神经细胞有关。  相似文献   
150.
The tRNA adaptation index (tAI) is a widely used measure of the efficiency by which a coding sequence is recognized by the intra-cellular tRNA pool. This index includes among others weights that represent wobble interactions between codons and tRNA molecules. Currently, these weights are based only on the gene expression in Saccharomyces cerevisiae. However, the efficiencies of the different codon–tRNA interactions are expected to vary among different organisms. In this study, we suggest a new approach for adjusting the tAI weights to any target model organism without the need for gene expression measurements. Our method is based on optimizing the correlation between the tAI and a measure of codon usage bias. Here, we show that in non-fungal the new tAI weights predict protein abundance significantly better than the traditional tAI weights. The unique tRNA–codon adaptation weights computed for 100 different organisms exhibit a significant correlation with evolutionary distance. The reported results demonstrate the usefulness of the new measure in future genomic studies.  相似文献   
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