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201.
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Lipoprotein (a) [Lp(a)], an LDL-like particle, has been proposed as a causal risk factor for CVD among general populations. Meanwhile, both serum Lp(a) and diabetes increase the risk of CVD. However, the relationship between serum Lp(a) and T2D is poorly characterized, especially in the Asian population. Therefore, we conducted a cross-sectional study in 10,122 participants aged 40 years or older in Jiading District, Shanghai, China. Our study found that the prevalence of T2D was decreased from 20.9% to 15.0% from the lowest quartile to the highest quartile of serum Lp(a) concentrations (P for trend <0.0001). Logistic regression analyses showed that the odds ratios and 95% confidence intervals of prevalent T2D for quartiles 2–4 versus quartile 1 were 0.86 (0.73–1.01), 0.88 (0.75–1.04), and 0.76 (0.64–0.90) (P for trend = 0.0002), after adjustment for traditional confounding factors. Moreover, the risks for prevalent prediabetes, insulin resistance, and hyperinsulinemia were also decreased from the lowest to the top quartile. This inverse association between serum Lp(a) and T2D was not appreciably changed after we adjusted hypoglycemic medications or excluded the subjects with hypoglycemic and/or lipid-lowering agents and/or a history of self-reported CVD.  相似文献   
203.
Novel reassortants of H7N9, H10N8, and H5N6 avian influenza viruses (AIVs) are currently circulating in China''s poultry flocks, occasionally infecting humans and other mammals. Combined with the sometimes enzootic H5N1 and H9N2 strains, this cauldron of genetically diverse AIVs pose significant risks to public health. Here, we review the epidemiology, evolution, and recent outbreaks of AIVs in China, discuss reasons behind the recent increase in the emergence of novel AIVs, and identify warning signs which may point to the emergence of a potentially virulent and highly transmissible AIV to humans. This review will be useful to authorities who consider options for the detection and control of AIV transmission in animals and humans, with the goal of preventing future epidemics and pandemics.  相似文献   
204.
玉米是重要的粮食作物,水稻黑条矮缩病毒(RBSDV)是玉米粗缩病的病原,由其引起的玉米粗缩病给玉米生产造成重大损失。利用人工mi RNA构建抗病毒植物的技术已经在多种植物中被证明有效,但是在玉米中的尝试未见报道。实验根据玉米zea-mi R159a的前体序列和RBSDV基因组中编码功能蛋白的基因和基因沉默抑制子的序列信息设计引物,构建了用于沉默RBSDV编码基因和基因沉默抑制子的ami RNA(Artificial mi RNA)基因。构建p CAMBIA3301-121-ami RNA植物表达载体,利用农杆菌介导法转化玉米自交系综31(Z31)。对转基因玉米进行分子检测,选择mi RNA表达量高的纯合体株系进行自然发病实验,按0-4的分级标准调查玉米粗缩病的严重度。结果表明,转抗粗缩病毒人工mi RNA载体玉米纯合体株系的抗病表现好于野生型玉米,其中针对基因组6的S6-mi R159转基因玉米抗病情况较好。研究表明利用人工mi RNA技术构建抗病毒病玉米新品种是可行的。  相似文献   
205.
The general aim of this study is to update the inventory of the fish species and to specify distribution patterns in the Nero River ichthyofauna in order to establish some basis for the conservation of these fish communities and their habitat. From February 2009 to January 2010, thirty-three sites were sampled monthly with gill nets and a backpack electrofisher, and environmental variables were recorded. Overall, 46 species included in 33 genuses, 24 families and 9 orders were collected. Eleven families and 30 species were the first records for the Nero River. Including all species previously listed in the literature, the number of species presently known in the Nero River and its tributaries is revised to 59. Four families, Alestidae (21%), Schilbeidae (19%), Cyprinidae (17%) and Cichlidae (16%) that made up 73% of the total number of the catches, were the most dominant. The most dominant numerical species were Schilbe mandibularis and Brycinus longipinnis. Fish species and sampling sites along with eight environmental variables were ordinated with canonical correspondence analysis (CCA) coupled to the Monte Carlo test. Ecological status based on fish assemblage according to environmental variables and anthropogenic pressures showed that miss dead wood leaves and roots, electrical conductivity, total dissolved solids, mud, nitrite, basin width, dissolved oxygen and pH, were the primary factors influencing fish distribution. The environmental tolerance index (ETI), ecological tolerance (tk) and optima (uk) values of 10 species to 8 different environmental variables were analyzed. Six species (Hemichromis fasciatus, Epiplatys chaperi, Barbus ablabes, B. longipinnis, Hemichromis bimaculatus and Chromidotilapia guntheri) have high ETI and a cosmopolitan distribution in the Nero River. In the tributaries of the middle course, high concentrations of nitrite in the water, added to the presence of a lot of tolerant species in the ichthyofauna are indications of disturbance of these areas. Subsequent recommendations were formulated for efficient restoration and conservation management of this River.  相似文献   
206.
207.
Pa A  Bi XT  Sokhansanj S 《Bioresource technology》2011,102(10):6167-6177
The replacement of natural gas combustion for district heating by wood waste and wood pellets gasification systems with or without emission control has been investigated by a streamlined LCA. While stack emissions from controlled gasification systems are lower than the applicable regulations, compared to the current base case, 12% and 133% increases are expected in the overall human health impacts for wood pellets and wood waste, respectively. With controlled gasification, external costs and GHG emission can be reduced by 35% and 82% on average, respectively. Between wood pellets and wood waste, wood pellets appear to be the better choice as it requires less primary energy and has a much lower impact on the local air quality.  相似文献   
208.
Apple chlorotic leaf spot virus (ACLSV), Apple stem pitting virus (ASPV), Apple stem grooving virus (ASGV) and Apple mosaic virus are economically important viruses infecting fruit tree species worldwide. To evaluate the occurrence of these pome fruit viruses in Latvia, a large‐scale survey was carried out in 2007. Collected samples were tested for infection by DAS ELISA and multiplex RT‐PCR. The accuracy of the detection of the viruses in multiplex RT‐PCR was confirmed by sequencing amplified PCR fragments. The results showed a wide occurrence of viruses in apple and pear commercial orchards established from non‐tested planting material. More than 89% of the tested apple trees and more than 60% of pear trees were infected with one or more pome fruit viruses. Analyses showed that the high occurrence of viruses in several apple cultivars is due to the propagation of infected clonal rootstocks and scions from infected mother trees. Sequence analyses targeting the 3′‐terminal region of the tested viruses showed various degrees of genetic diversity within respective virus isolates. This is the first report of the occurrence of ACLSV, ASGV and ASPV in apple and pear trees in Latvia and demonstrates their genetic diversity in different host genotypes.  相似文献   
209.
Oh Y  Bi E 《Trends in cell biology》2011,21(3):141-148
Septins are conserved GTP-binding proteins that assemble into hetero-oligomeric complexes and higher-order structures such as filaments, rings, hourglasses or gauzes. Septins are usually associated with a discrete region of the plasma membrane and function as a cell scaffold or diffusion barrier to effect cytokinesis, cell polarity, and many other functions. Recent structural studies of septin complexes have provided mechanistic insights into septin filament assembly, but key questions concerning the assembly, dynamics, and function of different septin structures remain to be answered.  相似文献   
210.
Production of recombinant human lysozyme in the milk of transgenic pigs   总被引:1,自引:0,他引:1  
In the swine industry pathogenic infections have a significant negative impact on neonatal survival. Piglets fed with human lysozyme, a natural antibiotic, might be more resistant to gastrointestinal infections. Here we describe the generation of transgenic swine expressing recombinant human lysozyme by somatic cell nuclear transfer. Three cloned female pigs were born, one of which expressed rhLZ at 0.32 ± 0.01 μg/ml in milk, 50-fold higher than that of the pig native lysozyme. Both the transgenic gilts and their progeny appear healthy. Introducing human lysozyme into pigs’ milk has a potential to benefit the piglets by enhancing immune function and defending against pathogenic bacteria, thereby increasing the new born survival rate. This advance could be of great value to commercial swine producers.  相似文献   
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