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91.
Soybean seed includes various bioactive substances. Also, they contain a variety of antinutritional factors including lipoxygenase, Kunitz trypsin inhibitor (KTI), lectin, and 7S α' subunit proteins. The genetic removal of these proteins will improve the nutritional value of soybean seed. The objective of this research was to breed new soybean with tetra recessive alleles (lox1lox2lox3/lox1lox2lox3ti/tile/lecgy1/cgy1) for lipoxygenase, KTI, lectin, and 7S α' subunit proteins. Seven parents were used to breed tetra null strain. SDS‐PAGE and Western blot analysis were used to determine the presence or absence of lipoxygenase, 7S α' subunit, KTI, and lectin proteins in mature seed. Tetra null soybean line has a purple flower, determinate growth habit, tan pod, and yellow seed coat colour. Stem height of the breeding line was 62.3 cm. The 100‐seed weight of the breeding line was 27.1 g and yield (t/ha) was 2.84. This is the first soybean strain with lox1lox2lox3/lox1lox2lox3ti/tile/lecgy1/cgy1 genotype (absence of lipoxygenase, KTI, lectin, and 7S α' subunit proteins).  相似文献   
92.
1953—1955年在晋南、北京等地对麦园蜘蛛及麦长腿蜘蛛的发生规律及生活习性进行了研究。结果明确两种麦蜘蛛一年中:秋季密度最大时期为11月上、中旬。春季密度最大的时期,麦园蜘蛛在3月下旬至4月上旬;麦长腿蜘蛛在5月上旬前后。两种麦蜘蛛均以滞育卵越夏。直至10月中旬,越夏卵始孵化,孵化最盛在11月上旬,此时幼、若虫出现最多,若进行防治可基本上防止以后的猖獗。根据结果分析,估计麦园蜘蛛每年发生2—3代,麦长腿蜘蛛发生3—4代。室内饲育初步观察麦园蜘蛛一世代(从卵到产卵)历时平均约57.8天;麦长腿蜘蛛为32.1天。两种麦蜘蛛都是单性生殖。麦长腿蜘蛛的滞育卵,具多年滞育习性,初步观察有些卵能在土中生活两年。两种麦蜘蛛的分布和猖獗都受湿度的影响,主要猖獗为害地区麦长腿蜘蛛在黄河以北的旱地;麦园蜘蛛在黄淮地区的水浇地或低洼地。耕作栽培对麦蜘蛛的发生有重要影响;连作对两种麦蜘蛛发生有利;深耕能将卵翻至深土之下,可以减少发生;晚播影响麦蜘蛛孵化后的食料。因此,合理轮作、深耕和适当晚播是综合防治中的重要措施。  相似文献   
93.
The use of mesenchymal stem cells (MSCs) has emerged as a potential new treatment for myocardial infarction. However, the poor viability of MSCs after transplantation critically limits the efficacy of this new strategy. The expression of microRNA-210 (miR-210) is induced by hypoxia and is important for cell survival under hypoxic conditions. Hypoxia increases the levels of hypoxia inducible factor-1 (HIF-1) protein and miR-210 in human MSCs (hMSCs). miR-210 positively regulates HIF-1α activity. Furthermore, miR-210 expression is also induced by hypoxia through the regulation of HIF-1α. To investigate the effect of miR-210 on hMSC survival under hypoxic conditions, survival rates along with signaling related to cell survival were evaluated in hMSCs over-expressing miR-210 or ones that lacked HIF-1α expression. Elevated miR-210 expression increased survival rates along with Akt and ERK activity in hMSCs with hypoxia. These data demonstrated that a positive feedback loop involving miR-210 and HIF-1α was important for MSC survival under hypoxic conditions.  相似文献   
94.
Recycled polyols from waste polyurethane (PU) foams were grafted onto PU to improve the properties such as tensile strength, shape recovery, low-temperature flexibility, and water compatibility. The recycled polyol was either purified by column chromatography before grafting or was used directly for grafting. The soft segment melting temperature of PU did not notably increase with the addition of polyol, whereas the glass transition temperature increased with increased polyol content. The tensile strength sharply increased at low polyol content and decreased at high polyol content, while the strain at break did not significantly change with an increase in polyol content. The shape recovery at 10 oC notably improved compared with unmodified PU and remained high after four cyclic tests. Polyol-grafted PU demonstrated better lowtemperature flexibility and reduced the water vapor permeability of PU membranes. Overall, grafting recycled polyol onto PU significantly improved the tensile stress, shape recovery, and low-temperature flexibility of PU.  相似文献   
95.
The aim of this study was to investigate the effects of (-)-epigallocatechin-3-gallate (EGCG) on newly developed high-fat/Western-style diet-induced obesity and symptoms of metabolic syndrome. Male C57BL/6J mice were fed a high fat/Western-style (HFW; 60% energy as fat and lower levels of calcium, vitamin D(3), folic acid, choline bitartrate, and fiber) or HFW with EGCG (HFWE; HFW with 0.32% EGCG) diet for 17 wks. As a comparison, two other groups of mice fed a low-fat diet (LF; 10% energy as fat) and high-fat diet (HF; 60% energy as fat) were also included. The HFW group developed more body weight gain and severe symptoms of metabolic syndrome than the HF group. The EGCG treatment significantly reduced body weight gain associated with increased fecal lipids and decreased blood glucose and alanine aminotransferase (ALT) levels compared to those of the HFW group. Fatty liver incidence, liver damage, and liver triglyceride levels were also decreased by the EGCG treatment. Moreover, the EGCG treatment attenuated insulin resistance and levels of plasma cholesterol, monocyte chemoattractant protein-1 (MCP-1), C-reactive protein (CRP), interlukin-6 (IL-6), and granulocyte colony-stimulating factor (G-CSF). Our results demonstrate that the HFW diet produces more severe symptoms of metabolic syndrome than the HF diet and that the EGCG treatment can alleviate these symptoms and body fat accumulation. The beneficial effects of EGCG are associated with decreased lipid absorption and reduced levels of inflammatory cytokines.  相似文献   
96.
Organic farming (OF) is a fast growing alternative for sustainable agriculture in Korea. However, information on the effects of OF on the soil properties and environmental conservation is limited. In order to determine the effects of OF on the soil properties, 31 fields under OF (hereafter referred to as "OF fields") and 61 fields under conventional farming (CF) (hereafter referred to as "CF fields") in plastic film houses were selected throughout Korea and the soil chemical properties were investigated, including the P distribution characteristics. Average organic matter (OM) content was significantly higher (44 g kg-1) in the OF fields then in the CF fields (24 g kg-1). Bray-2 P values were 986 and 935 mg kg-1 in the OF and CF soils, respectively, markedly exceeding the optimum range. Average total P (T-P) values were 2,973 mg kg-1 in the OF fields and 1,830 mg kg-1 in the CF fields. The high T-P values were due to repeated application of manure compost with a low N/P ratio. Inorganic P was the dominant fraction with 62–65% of T-P. The amounts of residual and organic P were significantly lower. The level of OF organic P was significantly higher (453 mg kg-1) compared to the 106 mg kg-1 value for the CF fields. Fractionation of soil inorganic P showed that Ca-P predominated with 1,332 mg kg-1 in the OF fields, which was associated with soil pH values over 6.0. The main inorganic P fraction in the CF soils whose pH values were generally less than 6.0 consisted of Al-/Fe-P. The levels of water-soluble P was significantly higher (65 mg kg-1) in the OF fields than in the CF fields (24 mg kg-1). These results indicated that the OF system may lead to a serious degradation of the soil environment due to the accumulation of phosphorus and may be an important source of water pollution compared to the CF systems in Korea.  相似文献   
97.
Stylosanthes guianensis is a popular pasture legume and cover crop. The legume possessed strong allelopathic potential and suppressed spontaneous growth of paddy weeds. In a bioassay, aqueous extract of S. guianensis remarkably inhibited germination and growth of barnyardgrass and monochoria. Application of 1 ton ha?1 upland parts of S. guianensis significantly reduced paddy weed biomass by 80 % and increased rice yield by 40 % when compared with the control. Gas chromatography‐mass spectrometry analysis reveals the presence of several allelochemicals in S. guianensis including phenolic acids, coumarin and long‐chain fatty acids. Stylosanthes guianensis may be used as a source of natural herbicide for reducing the dependency on synthetic herbicides in agricultural production.  相似文献   
98.
The genome segments of two electrophoretically distinct variants of bluetongue virus (BTV) Serotype 2 (Ona A and Ona B) from the U.S.A. were analyzed by double-dimension gel electrophoresis of RNase T1 produced oligonucleotides. Segments 1, 4, 5, 6, 7 and 10 were examined individually after separation by SDS-PAGE; and Segments 2 and 3, and 8 and 9, which were difficult to resolve, were fingerprinted as pairs. The Ona A and Ona B strains appeared to be closely related since corresponding segments were comparable, sharing 53–89% of the large oligonucleotides counted. Since the strains with the Ona A electropherotype preceded Ona B infection in Florida, U.S.A. and since Ona A was indistinguishable from the early African isolate of Serotype 2, Ona B was thought to be a variant of an Ona A strain. These data tend to support the hypothesis that Ona B could have evolved from Ona A as the result of point mutations or genetic drift.  相似文献   
99.
SUMMARY: Australian lentogenic Newcastle disease viruses were evaluated as uninactivated vaccines in Australian chickens, the response being evaluated by the production of haemagglutination-inhibition (HI) antibodies. Two viruses, V4 and PM9, induced high levels of antibody and were readily transmissible between chickens by contact exposure. Three other viruses were poorly immunogenic and poorly transmissible. Chickens vaccinated intramuscularly with the V4 strain produced higher HI antibody titres than chickens vaccinated by the orotracheal, intranasal and intraocular routes. HI antibody titres in chickens vaccinated with the V4 strain reached peak levels 3 to 5 weeks after vaccination and waned considerably during the next 2 to 4 weeks. However, low levels of HI antibody persisted for at least 36 weeks after vaccination. Intramuscular vaccination with the V4 strain of one-day-old chicks lacking maternal antibody to Newcastle disease virus resulted in 42–70% mortality and the survivors developed very high titres of HI antibody. Similar chickens inoculated orotracheally showed signs of depression and developed high titres of HI antibody, but there were no mortalities. Chickens 1-, 2-, 3- and 4-weeks-old and lacking maternally derived HI antibody to Newcastle disease virus suffered no adverse reaction to intramuscular or orotracheal vaccination. The antibody response of the 1-week-old chickens was considerably poorer than that of the older chickens. Following orotracheal vaccination with the V4 strain, chickens with low levels of maternally derived antibody responded with low levels of HI antibody. On the other hand, in the progeny of hens hyperimmunised with the V4 strain the production of active antibody following orotracheal vaccination was delayed until the level of passive antibody had declined considerably. There was no response to intramuscular vaccination in congenitally hyperimmune chickens. The minimum HI antibody inducing dose of V4 vaccine, when measured 3 weeks after vaccination of 6-weeks-old chickens, was 105.6 50% egg infectious doses.  相似文献   
100.
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