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961.
A number of genes that contribute to the domestication traits of cultivated rice have been identified. These include Sh4, Rc, PROG1 and LABA1, which are associated with non-shattering rachis, white pericarp, erect growth and barbless awns, respectively. The mutations giving rise to the “domestication alleles” of these genes are either invariable in cultivated rice, or have variability that is strictly associated with the phenotypic trait. This observation forms the basis to those current rice domestication models that envisage a single origin for the domesticated phenotype. Such models assume that the domestication alleles are absent or rare in wild rice, emerged under cultivation and spread across all rice groups by introgressive hybridization. We examined whole-genome sequencing datasets for wild and cultivated rice to test the former two assumptions. We found that the rc and laba1 alleles occur in wild rice with broad geographical distribution, and reach frequencies as high as 13 and 15%, respectively. These results are in agreement with previous observations of the prog1 and sh4 domestication alleles in wild populations. We also show that the diversity of the genomic regions surrounding the rc, laba1, prog1 and sh4 alleles in wild accessions is greater than that in cultivated rice, suggesting that these alleles emerged prior to domestication. Our findings indicate that the possibility that independent rice groups obtained identical domestication alleles directly from the wild population needs to be considered.  相似文献   
962.
Infectious bronchitis virus (IBV) Cal99 variant was isolated from the kidneys of seven 2-5-mo-old game chickens with nephritis and respiratory disease. IBV Cal99 variant is usually associated with respiratory disease in broiler chickens in California. Macroscopically, the majority of the birds had moderately to severely enlarged and mottled pale kidneys, with increased urates in the ureters. Microscopically, most of the birds had acute nephrosis and interstitial nephritis. The birds also had sinusitis, tracheitis, bronchopneumonia, airsacculitis, salivary gland adenitis, and lymphoid depletion in the thymus and bursa of Fabricius. Immunohistochemistry was strongly positive for IBV antigen in the cytoplasm of tubular epithelial cells in the kidneys and also in the epithelium of the respiratory tract, salivary glands, proventriculus, intestine, and bursa of Fabricius. Infectious bronchitis virus was isolated from the trachea, lungs, kidneys, and cecal tonsils. Sequencing of the hypervariable region of the S1 gene of the kidney IBV isolate, designated IBV/CA99variant/07, revealed that the virus was 98% homologous to the Cal99 serotype of IBV.  相似文献   
963.
Meat quality of Iberian pigs is defined by the combination of their genetic characteristics and the particular production system. To carry out a genetic analysis of the main meat quality traits, we estimated their heritabilities, genetic correlations and the association effects of 32 selected SNPs of 12 candidate genes. A total of ten traits were measured in longissimus dorsi samples from 1,199 Iberian pigs fattened in the traditional free-range system: water holding capacity (thawing, cooking and centrifuge force water losses), instrumental colour (lightness L*, redness a* and yellowness b*), myoglobin content, shear force on cooked meat, and shear force and maximum compression force on dry-cured loin. Estimated heritability values were low to moderate (0.01 to 0.43) being the lowest for L* and the highest for cooking loss. Strong genetic correlations between water holding capacity traits (0.93 to 0.96) and between myoglobin content and a* (0.94) were observed. The association analyses revealed 19 SNPs significantly associated with different traits. Consistent and strong effects were observed between PRKAG3 SNPs (rs319678464G > C and rs330427832C > T), MYH3_rs81437544T > C, CASP3_rs319658214G > T and CTSL_rs332171512A > G and water losses. Also for CAPN1_rs81358667G > A and CASP3_rs319658214G > T and shear force. The SNPs mapping on PRKAG3 showed the highest effects on Minolta colour traits. Genotyping of these SNPs could be useful for the selection of Iberian young boars with similar estimated breeding values for productive traits.  相似文献   
964.
Investigation of polar extracts from ripe fruits of Capsicum annuum L. var. acuminatum yielded three new glycosides, capsosides A (1) and B (2) and capsianoside VII (3), along with seven known compounds (4-10). The chemical structures were elucidated mainly by extensive nuclear magnetic resonance methods and mass spectrometry, and the biological activities of icariside E(5) (4) were tested by different assays. Icariside E(5), in contrast to capsaicin, neither induces an increase in the intracellular levels of reactive oxygen species nor affects the mitochondria permeability transition, and it does not signal through the vanilloid receptor type 1. Interestingly, this compound protects Jurkat cells from apoptosis induced by the oxidative stress mediated by serum withdrawal. These results suggest that icariside E(5) may have antioxidant properties that strengthen the importance of peppers in the Mediterranean diet.  相似文献   
965.
Water activity (aw)of Amaranthus cruentus were measured at 35, 45, and 65°C at different moisture contents by means of an electronic water activity meter. Experimental curves were fitted to one three-parameter equation (GAB equation). The equilibrium values and temperature shifts were modeled with a three-parameter equation in the approximate aw range of 0.03–0.88. An analytical expression to calculate the isosteric heat of sorption and its moisture content dependence was used, and the results were compared with the isosteric heat calculated from the experimental equilibrium data by means of the Clausius-Clapeyron equation.  相似文献   
966.
Mycorrhizal and non-mycorrhizal holm oak (Quercus ilex L.) seedlings inoculated with black truffle (Tuber melanosporum) were grown under nursery conditions and subjected to drought hardening for 4 months in autumn and winter followed by irrigation for 10 days. Leaf water potential and stomatal conductance were monitored during the 4 months of drought. When the test was completed (March), measurements were made for each treatment (inoculated or non-inoculated), and watering regime (watered and water-stressed). Pressure–volume curves, osmotic potential at full turgor, osmotic potential at zero turgor and the tissue modulus of elasticity near full turgor were calculated. Mycorrhizal colonization and growth, and the content of the main mineral nutrients N, P, K, Ca and Mg were measured. Water stress affected plant growth, caused an elastic adjustment of the plant tissues, and decreased the P and K content, and inoculation improved the nitrogen content. Drought acclimation apparently achieved the goal of improving the drought tolerance of holm oak seedlings, without depressing ectomycorrhizal root colonization by T. melanosporum. José Antonio Rodríguez Barreal—Deceased  相似文献   
967.
【目的】明确天然产物斑蝥素的杀虫谱和作用方式。【方法】采用不同生测方法,测定斑蝥素及1.0%斑蝥素乳油对11种害虫的室内毒力,观察了家蝇成虫的中毒症状。【结果】斑蝥素对家蝇成虫具有一定的胃毒作用,其48,72h的胃毒LC50分别为781.90,397.23mg/L,无触杀、熏蒸作用,其中胃毒作用较缓慢,处理约18h后才表现出明显的中毒症状;对玉米象成虫的48h胃毒LC50和触杀LD50分别为373.17mg/L和0.36μg/虫,无熏蒸活性;对大叶黄杨斑蛾4龄幼虫的24,48h触杀LD50分别为0.084,0.049μg/虫;1.0%斑蝥素乳油对烟蚜、菊姬长管蚜、桃粉蚜、萝卜蚜和月季长管蚜5种蚜虫无翅成蚜的12h触杀LC50分别为19.52,15.84,16.63,25.94,26.20mg/L;1.0%斑蝥素乳油对朱砂叶螨、麦圆蜘蛛和山楂叶螨成螨的12h触杀LC50分别为8.26,13.38,8.46mg/L。【结论】斑蝥素对多种害虫均具有不同程度的毒杀作用,其主要作用方式为触杀和胃毒。  相似文献   
968.
Cockatiels are popular pets. Still, despite medical and surgical relevance, the radiographic anatomy of the cockatiel (Nymphicus hollandicus) skeleton, like that of different wild and exotic bird species, has seldom been described. This study set out to describe the radiographic anatomy of the cockatiel skeleton. Twelve adult male and nine adult female specimens were radiographed using a digital X-ray system and different views. The radiographic anatomy of these birds was similar to that of other Psittacidae. However, some particularities inherent to the target species were detected, such as the presence of four flexion zones in the skull (craniofacial, nasal, jugal arch and palatine), complete bony orbit comprising a suborbital arch, 34–38 vertebrae (10 or 11 cervical, 8 or 9 thoracic, 9 or 10 lumbosacral, 5 or 6 caudal vertebrae and a pygostyle comprising 2 fused vertebrae), eight or nine pairs of ribs and a notarium made up of fused T2–T6 vertebrae. Poor radiopacity of the notarium, ribs and respective uncinate processes, and synsacral vertebrae made demarcation of these structures difficult. The appendicular skeleton of the cockatiel was very similar to that of other Psittacidae, and there were no gender-related differences.  相似文献   
969.
It has been reported that the nucleotide sequences of the mitochondrial and nuclear genes of Takifugu pufferfish torafugu T. rubripes and karasu T. chinensis show 99–100% sequence identity, indicating a very close relationship between the two species. To further investigate this genetic relationship, we compared genetic variation at four microsatellite loci and at the mitochondrial control region (CR) (561 bp) between groups of T. rubripes caught at two locations [TrG, caught in the Genkai Sea off Tsushima Island in 2003 (n = 50); TrS, caught in the Suwo Sea off Kita-Kyushu in 2008 (n = 50)] and T. chinensis caught at one location (TcK, caught off the east coast of Korea in 2004; n = 50). Analyses using microsatellite loci showed that genetic diversity index values of the TrG, TrS and TcK groups were 0.9505, 0.9350 and 0.9335, respectively, while values of genetic distance and genetic differentiation between TrG and TcK (0.0543 and 0.0189, respectively) were smaller than those between TrG and TrS (0.0857 and 0.0194, respectively). Analyses using CR for the same specimens showed that genetic distances were consistent with those obtained using microsatellite loci. These results, together with our previous observations, suggest that T. rubripes and T. chinensis are very closely related and possibly can be regarded as the same species.  相似文献   
970.
In Japan, Lactococcus garvieae infection has been the main fish disease in aquaculture. Although commercial oral and injectable vaccines have been used to prevent L. garvieae infection in Japan, L. garvieae has been isolated not only from unvaccinated fish but also from vaccinated fish in which immunity induced by vaccination had diminished. In order to obtain epidemiological information on this fish pathogen, we conducted biased sinusoidal field gel electrophoresis (BSFGE) pattern analysis and phage typing of L. garvieae isolates (n = 427) from fish in Japan. These isolates were obtained from 13 different fish species between 1980 and 2007. In the BSFGE analysis, L. garvieae isolates were classified into 17 groups (S1–S17) based on the SmaI digestion patterns and into four groups (A1–A4) based on the ApaI digestion patterns. Phage typing revealed five different phage susceptibility profiles (A–E) in L. garvieae isolates. Since 2005, comparisons of the results of phage typing and BSFGE have indicated the presence of a novel genotype (S16/A4) with phage type E. All the strains belonging to this type showed lincomycin sensitivity.  相似文献   
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