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11.
The primary structure of human apolipoprotein (apo) B-48 has been deduced and shown by a combination of DNA excess hybridization, sequencing of tryptic peptides, cloned complementary DNAs, and intestinal messenger RNAs (mRNAs) to be the product of an intestinal mRNA with an in-frame UAA stop codon resulting from a C to U change in the codon CAA encoding Gln2153 in apoB-100 mRNA. The carboxyl-terminal Ile2152 of apoB-48 purified from chylous ascites fluid has apparently been cleaved from the initial translation product, leaving Met2151 as the new carboxyl-terminus. These data indicate that approximately 85% of the intestinal mRNAs terminate within approximately 0.1 to 1.0 kilobase downstream from the stop codon. The other approximately 15% have lengths similar to hepatic apoB-100 mRNA even though they have the same in-frame stop codon. The organ-specific introduction of a stop codon to a mRNA appears unprecedented and might have implications for cryptic polyadenylation signal recognition and RNA processing.  相似文献   
12.
The distribution of various molecular species of triacylglycerols (TAGs) and phospholipids among three corn kernel parts was determined by LC/ESI-MS. A comparison between three corn kernel parts demonstrated that there was a significant (p < 0.05) difference in their contents of various glycerophospholipid classes. Phosphatidylcholine was the most abundant class in germ and pericarp fractions (51.4–70.6% of the total glycerophospholipids), followed by phosphatidylinositol (11.3–25.1%) and phosphatidylethanolamine (8.4–12.6%). In contrast, phosphatidylethanolamine was found to be the most abundant class in the endosperm fraction (41.4–48.5%), followed by phosphatidylcholine (30.2–33.4%) and phosphatidylinositol (13.2–14.4%). Various molecular species were detected in each class of glycerophospholipid and their levels were significantly (p < 0.05) different among three corn kernel fractions. The major molecular species of triacylglycerol detected in three corn parts were OLL, OOL, LLL, POL, PLL, OOO and POO; where L represents linoleic acid; O, oleic acid; and P, palmitic acid. The TAG composition was significantly different among three corn kernel fractions. In Astro germ fraction, LLL (27.2%) was detected as the dominant TAG molecular species, followed by OLL (21.9%) and PLL (13.4%); however in Astro endosperm fraction, OLL (21.5%) was the major form followed by PLL (18.6%) and LLL (13.5%).  相似文献   
13.
Summary

The phenology of wild stands of strawberry guava (Psidium cattleianum Sabine) was studied at 100, 480 and 720.m over 2 years in ReÂunion Island. The shoots bore flower buds at the basal nodes, and vegetative buds at the apical nodes. Trees produced vegetative growth from September to December, flowers from November to January and fruit from February to June. Shoot growth was earlier at 100 and 720.m the first year, but were synchronized in the second year. Flowering and fruiting were also earlier at 100.m. The intervals between shoot emergence and flowering, and flowering and fruit maturity were strongly related to temperature, with base temperatures of 5.58C and 2.68C, and heat units requirements of 675 and 2,5528C.d, respectively. The number of shoots, flowers and fruit per branch varied across sites and years, unrelated to temperature. However, production was significantly higher at 720.m. Production was much lower after a hurricane. Flowering (y) was related to shoot production per branch (x) (log(y)=111.33.log(x); r2.=.0.78), whereas the fruit set rate was highly variable between trees (26±100%). The number of fruits per branch (1±6) was possibly related to poor shoot growth or fruit set, but unrelated to the timing of the phenological events. It is expected that commercial orchards would be more productive than feral stands.  相似文献   
14.
Resistance to the fungicide boscalid in laboratory mutants of Botryotinia fuckeliana (Botrytis cinerea) was investigated. The baseline sensitivity to boscalid was evaluated in terms of colony growth (EC50 = 0.3–3 μg ml−1; MIC = 10–30 μg ml−1) and conidial germination (EC50 = 0.03–0.1 μg ml−1; MIC = 1–3 μg ml−1) tests. Mutants were selected in vitro from wild-type strains of the fungus on a fungicide-amended medium containing acetate as a carbon source. Mutants showed two different levels of resistance to boscalid, distinguishable through the conidial germination tests: low (EC50 ∼ 0.3 μg ml−1, ranging from 0.03 to 1 μg ml−1; MIC > 100 μg ml−1) and high (EC50 > 100 μg ml−1) resistance. Analysis of meiotic progeny from crosses between resistant mutants and sensitive reference strains showed that resistant phenotypes were due to mutations in single major gene(s) inherited in a Mendelian fashion, and linked with both the Daf1 and Mbc1 genes, responsible for resistance to dicarboximide and benzimidazole fungicides, respectively. Gene sequence analysis of the four sub-units of the boscalid-target protein, the succinate dehydrogenase enzyme, revealed that single or double point mutations in the highly conserved regions of the iron-sulphur protein (Ip) gene were associated with resistance. Mutations resulted in proline to leucine or phenylalanine replacements at position 225 (P225L or P225F) in high resistant mutants, and in a histidine to tyrosine replacement at position 272 (H272Y) in low resistant mutants. Sequences of the flavoprotein and the two transmembrane sub-units of succinate dehydrogenase were never affected.  相似文献   
15.
The objective of this study was to evaluate the effects of two methods of early-age water restriction on performance, some immune responses, serum metabolites, and prevalence of leg weakness in broiler chicks. One-hundred-eighty-seven-day-old chicks (Ross 308) were allocated to three treatments with four replicates based on a completely randomized design. Treatments included the control group, where birds had free access to water, and water-restricted groups, where access to water was limited to three 2-h periods (WRT1) or a 12-h period (WRT2) per day from days 7 to 17. Chicks in the control group were significantly heavier (P < 0.05) at 17 and 46 days of age compared to the restricted birds. In the WRT2 group, feed intake decreased significantly over the 17- to 28-day period while feed conversion ratio was poorer during water restriction (P < 0.05). Antibody titers against Newcastle and SRBC were higher (P < 0.05) for chicks with ad libitum access to water. Birds in the restricted groups exhibited a higher heterophil to lymphocyte ratio compared to the control group (P < 0.05). The treatments had no significant impact on serum metabolites including protein, triglyceride, total cholesterol, high-density lipoprotein and low-density lipoprotein cholesterols, calcium, and phosphorus concentrations. Walking ability, tibial dyschondroplasia, foot pad, hock burn, and valgus/varus angulation were not significantly influenced by water restriction. In conclusion, the current results indicate that early-age water restriction negatively influenced productive traits and immunological responses of broiler chicks and failed to have any favorable impacts on leg health.  相似文献   
16.
Tropical Animal Health and Production - The objective of this study was to monitor the changes in growth, dry matter intake, and blood profiles (nutrition and reproductive hormones) of dairy...  相似文献   
17.
Background:Let-7f has essential impacts on biological processes; however, its biological and molecular functions in lung cancer pathogenesis have yet been remained unclear. We aimed to investigate the expression level of let-7f and its candidate target genes both in lung cancer tissues and A549 cell line. Methods:Bioinformatics databases were first used to select candidate target genes of let-7f. Then the relative gene and protein expressions of let-7f and its target genes, including HMGA2, ARID3B, SMARCAD1, and FZD3, were measured in lung tissues of Non-Small Cell Lung Cancer (NSCLC) patients and A549 cell line using quantitative real-time PCR and Western blotting. The electroporation method was used to transfect A549 cells with let-7f mimic and microRNA inhibitor. The impact of let-7f transfection on the viability of A549 cells was assessed using MTT assay. The expression data of studied genes were analyzed statistically Results:Results indicated significant downregulated expression level of let-7f-5p (p = 0.0013) and upregulated level of the HMGA2 and FZD3 in NSCLC cases (p < 0.05). In A549 cells, after transfection with let-7f mimic, the expression of both mRNA and protein levels of HMGA2, ARID3B, SMARCAD1, and FZD3 decreased. Also, the overexpression of let-7f significantly inhibited the A549 cell proliferation and viability (p = 0.017). Conclusion:Our findings exhibited the high value of let-7f and HMGA2 as biomarkers for NSCLC. The let-7f, as a major tumor suppressor regulatory factor via direct targeting genes (e.g. HMGA2), inhibits lung cancer cell viability and proliferation and could serve as a marker for the early diagnostic of NSCLC.Key Words: MicroRNAs, Biomarkers, Carcinoma, Non-Small-Cell Lung  相似文献   
18.
Boron (B) is one of the important micronutrient required for rice in particular during reproductive growth. A laboratory study was conducted to explore the potential of boron nutripriming in improving the germination and early seedling growth of rice. Seeds of fine grain aromatic rice cultivar Super Basmati were primed in aerated B solution (0.001, 0.01, 0.1 and 0.5% w/v) while untreated dry seeds were taken as control. Seed priming in 0.001 and 0.1% B solutions improved the time to 50% germination, germination energy, final germination percentage, mean germination time, and germination index. Beyond this concentration either there was no effect or an adverse effect on rice seeds. In the cases of radicle length, plumule length and secondary roots priming more diluted B solution, i.e., 0.001% proved better than rest of the treatments as suppression in these three traits was observed by other B treatments than control. Seed priming in relatively concentrated B solution, i.e., 0.5% completely suppressed the germination and growth.  相似文献   
19.
Farmyard manure (FYM) improves various soil parameters and to a large extent, the availability of water and nutrient to crops when it is applied to the soil. This study aims to further investigate the short-term effects of different levels of FYM on maize plants and soil parameters. Maize plants grown in pot culture were treated with no FYM (control), recommended NPK (inorganic fertilizers), and FYM at 2, 4, 6, 8, and 10 t ha?1 along with recommended NPK, and the cultures were analyzed 8 weeks after germination. Soil bulk density and soil pH decreased with the increasing levels of FYM, whereas soil porosity, soil organic matter (SOM), soil water content, plant height, root and shoot yield, and NPK uptake of maize were increased compared with the control or recommended NPK, respectively. The present results indicate that short-term application of higher FYM levels improves soil properties. Furthermore, the application of FYM at only higher rates significantly increases the nutrient uptake of maize plants due to improved soil properties. The supply of different amounts of nutrients increases biomass and nutrient uptake in plants.  相似文献   
20.
Mohammed  S.  Khallouf  A.  Kiwan  S.  Alhenawi  S.  Ali  H.  Harsányi  E.  Kátai  J.  Habib  H. 《Eurasian Soil Science》2020,53(4):420-429
Eurasian Soil Science - Soil is one of the most important natural resources that should be studied and characterized to provide decision-makers with sufficient information for reconstruction plans...  相似文献   
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