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71.
It is difficult to isolate sufficient quantities of high-quality RNA from apple fruit. An abundance of polyphenolic compounds and polysaccharides and a relatively low concentration of RNA in the fruit tissue create conditions that hamper RNA isolation when standard techniques are used. We have developed two RNA isolation methods that include an initial homogenization and extraction with acetone or ethanol. These in turn remove the interfering compounds and precipitate the protein and nucleic acids for subsequent RNA extraction. The quality of RNA was satisfactory with both acetone and ethanol preparations; however, the acetone powder produced consistently higher quantities of RNA.  相似文献   
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Saeed MA  Sabir AW 《Fitoterapia》2004,75(1):81-84
The irritant potentials of essential oil and seven sesquiterpenoids compounds newly isolated from the oleo-gum-resin of Commiphora myrrha were investigated by open mouse ear assay. The essential oil, curzerenone, furanodiene-6-one and furanoeudesma-1,3-diene showed potent and persistent irritant effects while others possess least irritant potentials.  相似文献   
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In 2007–2009, severe virescence, malformation and twisting of flower spikes and yellowing of entire plants were observed in various Gladiolus cultivars growing in the gardens of the National Botanical Research Institute, Lucknow, India. The disease symptoms were very similar to symptoms in Gladiolus caused by the Aster yellows phytoplasma identified from Poland. Disease incidence was low (1.1–3.4%), but the severity of symptoms was high. A phytoplasma infection was detected in nine of 13 cultivars by PCR followed by nested PCR using universal phytoplasma primers P1/P6 or R16F2n/R16R2, respectively. An amplicon of ~1.2 kb obtained from the nested PCR was cloned and sequenced. Sequence analysis of the PCR amplicon revealed high (94–98%) identities and the closest phylogenic relationships with several isolates of Aster yellows phytoplasma of ‘Candidatus Phytoplasma asteris’ (16SrI group). Thus, the phytoplasma isolate of Gladiolus was identified as a new isolate of ‘Ca. P. asteris’ (16SrI group). In silico analysis of the phytoplasma isolate clearly indicated that the isolate was distinct from other Indian isolates of this phytoplasma.  相似文献   
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The present study evaluated the effects of Saccharomyces boulardii on duodenal digestive enzymes, morphology and cytokine induction response in broiler chicken. A total of 200 birds were allotted into two groups (n = 100) and each group divided into five replications (n = 20). The control group was fed basal diet in addition to antibiotic (virginiamycin 20 mg/kg), and treatment group received (1 × 108 colony‐forming units/kg feed) S. boulardii in addition to basal diet lasting for 72 days. The results compared to control group revealed that adenosine triphosphatase, gamma glutamyl transpeptidase, lipase and trypsin activities were higher, while, no significant improvement was observed in amylase activities in the duodenum of the treatment group. Moreover, morphological findings showed that villus height, width and number of goblet cells markedly increased. Additionally, transmission electron microscopy visualized that villus height, width and structural condensation significantly increased in the treatment group. The immunohistological observations showed increased numbers of immunoglobulin A (IgA)‐positive cells in the duodenum of the treatment group. Meanwhile, cytokine production levels of tumor necrosis factor‐α, interleukin (IL)‐10, transforming growth factor‐β and secretory IgA markedly increased, and IL‐6 statistically remained unchanged as compared to the control group. These findings illustrated that initial contact of S. boulardii to the duodenum has significant impact in improving enzymatic activity, intestinal morphology and cytokine response in broiler chicken.  相似文献   
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Acacia hybrids offer a great potential for paper industry in Southeast Asia due to their fast growth and ability to grow on abandoned or marginal lands. Breeding Acacia hybrids with desirable traits can be achieved through marker assisted selection (MAS) breeding. To develop a MAS program requires development of linkage maps and QTL analysis. Two mapping populations were developed through interspecific hybridization for linkage mapping and QTL analysis. All seeds per pod were cultured initially to improve hybrid yield as quality and density of linkage mapping is affected by the size of the mapping population. Progenies from two mapping populations were field planted for phenotypic and genotypic evaluation at three locations in Malaysia, (1) Forest Research Institute Malaysia field station at Segamat, Johor, (2) Borneo Tree Seeds and Seedlings Supplies Sdn, Bhd. (BTS) field trial site at Bintulu, Sarawak, and (3) Asiaprima RCF field trial site at Lancang, Pahang. During field planting, mislabeling was reported at Segamat, Johor, and a similar problem was suspected for Bintulu, Sarawak. Early screening with two isozymes effectively selected hybrid progenies, and these hybrids were subsequently further confirmed by using species-specific SNPs. During field planting, clonal mislabeling was reported and later confirmed by using a small set of STMS markers. A large set of SNPs were also used to screen all ramets in both populations. A total of 65.36% mislabeled ramets were encountered in the wood density population and 60.34% in the fibre length mapping population. No interpopulation pollen contamination was detected because all ramets found their match within the same population in question. However, mislabeling was detected among ramets of the same population. Mislabeled individuals were identified and grouped as they originated from 93 pods for wood density and 53 pods for fibre length mapping populations. On average 2 meiotically unique seeds per pod (179 seeds/93 pods) for wood density and 3 meiotically unique seeds per pod (174 seeds/53 pods) for fibre length mapping population were found. A single step statistical method was used to evaluate the most informative set of SNPs that could subsequently be used for routine checks for mislabeling in multi-location field trials and for labelling superior clones to protect breeder’s rights. A preliminary set of SNPs with a high degree of informativeness was selected for the mislabeling analysis in conjunction with an assignment test. Two subsets were successfully identified, i.e., 51 SNPs for wood density and 64 SNPs for fibre length mapping populations to identify all mislabeled ramets which had been previously identified. Mislabeling seems to be a common problem due to the complexity involved in the production of mapping populations. Therefore, checking for mislabeling is imperative for breeding activities and for analyses such as linkage mapping in which a correlation between genotypic and phenotypic data is determined.  相似文献   
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1. Rice bran processed by extrusion cooking, roasting or pelleting and treated with antioxidant was used in broiler starter and finisher diets at various concentrations up to 500 g/kg. 2. Extrusion cooking gave the best performance, followed by roasting, while non-significant differences were observed between raw and pelleted bran. 3. Increasing the amount of rice bran in broiler diets resulted in significantly negative effects on growth performance. Non-significant differences were observed in mortality and dressing percentage due to different processes and concentrations of rice bran in the diet. Organ weights were significantly higher on raw and pelleted rice bran as compared to extruded and roasted bran. Liver and heart weights significantly increased with increasing contents of rice bran above 200g/kg, while pancreas weight increased with an addition of rice bran. 4. Treating the rice bran with antioxidant up to 250ppm had non-significant effects on broiler performance.  相似文献   
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Spawning in Labeo bata occurs during July and August. Each individual spawns only once, with the onset of spawning directly dependent on the monsson season. Its success depends upon the access of gravid fish to a suitable spawning ground. The average fecundity is 192 785.  相似文献   
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