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排序方式: 共有469条查询结果,搜索用时 15 毫秒
91.
92.
H. Zareian H. R. Esmaeili A. Gholamhosseini N. Alwan B. W. Coad 《Journal of Ichthyology》2018,58(3):283-295
Capoeta mandica was originally described as C. barroisi mandica from Mond River, Persian Gulf basin, based on morphological characters and later was considered as a distinct species based on a few small specimens. However, there is still controversial debate about its systematic position and morphological characters. To resolve the issue, new collected specimens from Iranian drainage basins examined morphologically and molecularly. Results revealed that C. mandica is a distinct taxon in the Capoeta trutta group. This taxon confirms the zoogeographical separation of the Persis basin (southern Iran) by the rise in post-Pleistocene sea level, isolating rivers from the Tigris-Euphrates and western basins. 相似文献
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Tsai HJ Shaikh N Kho JY Battle N Naqvi M Navarro D Matallana H Lilly CM Eng CS Kumar G Thyne S Watson HG Meade K LeNoir M Choudhry S Burchard EG;Study of African Americans Asthma Genes Environments 《Human genetics》2006,119(5):547-557
Beta2-adrenergic receptor (beta2AR) gene polymorphisms have been reported to be associated with various asthma-related traits in different racial/ethnic populations. However, it is unknown whether beta2AR genetic variants are associated with asthma in African Americans. In this study, we have examined whether there is association between beta2AR genetic variants and asthma in African Americans. We have recruited 264 African American asthmatic subjects and 176 matched healthy controls participating in the Study of African Americans, Asthma, Genes and Environments (SAGE). We genotyped seven known and recently identified beta2AR SNP variants, then tested genotype and haplotype association of asthma-related traits with the beta2AR SNPs in our African American cohort with adjustment of confounding effect due to admixture background and environmental risk factors. We found a significant association of the SNP -47 (Arg-19Cys) polymorphism with DeltaFEF(25-75), a measure of bronchodilator drug responsiveness, in African American asthmatics after correction for multiple testing (P = 0.001). We did not observe association of the SNP +46 (Arg16Gly) variant with asthma disease diagnosis and asthma-related phenotypes. In contrast to previous results between the Arg16Gly variant and traits related to bronchodilator responsiveness, our results indicate that the Arg-19Cys polymorphism in beta upstream peptide may play an important role in bronchodilator drug responsiveness in African American subjects. Our findings highlight the importance of investigating genetic risk factors for asthma in different populations. 相似文献
96.
Identification of Stk25 as a genetic modifier of Tau phosphorylation in Dab1-mutant mice 总被引:1,自引:0,他引:1
Matsuki T Zaka M Guerreiro R van der Brug MP Cooper JA Cookson MR Hardy JA Howell BW 《PloS one》2012,7(2):e31152
Hyperphosphorylation of the microtubule binding protein Tau is a feature of a number of neurodegenerative diseases, including Alzheimer's disease. Tau is hyperphosphorylated in the hippocampus of dab1-null mice in a strain-dependent manner; however, it has not been clear if the Tau phosphorylation phenotype is a secondary effect of the morbidity of these mutants. The dab1 gene encodes a docking protein that is required for normal brain lamination and dendritogenesis as part of the Reelin signaling pathway. We show that dab1 gene inactivation after brain development leads to Tau hyperphosphorylation in anatomically normal mice. Genomic regions that regulate the phospho Tau phenotype in dab1 mutants have previously been identified. Using a microarray gene expression comparison between dab1-mutants from the high-phospho Tau expressing and low-phospho Tau expressing strains, we identified Stk25 as a differentially expressed modifier of dab1-mutant phenotypes. Stk25 knockdown reduces Tau phosphorylation in embryonic neurons. Furthermore, Stk25 regulates neuronal polarization and Golgi morphology in an antagonistic manner to Dab1. This work provides insights into the complex regulation of neuronal behavior during brain development and provides insights into the molecular cascades that regulate Tau phosphorylation. 相似文献
97.
Thirty-eight adult ewes were superovulated following a 12 d progestagen treatment in association with either 135 mg crude horse anterior pituitary extract (HAP) or 30 mg soluble HAP with or without 1000 IU human chorionic gonadotrophin (hCG). Soluble HAP in combination with hCG significantly (P < 0.01) increased the ovulation rate as compared to HAP alone (14.5 vs 5.3, respectively). The number of oocytes recovered per ewe showing estrus following soluble HAP and HCG (6.9) was higher than after HAP alone (3.3), but this difference was not significant. A significantly higher (P < 0.05) ovulation rate and ovarian response were obtained following crude HAP than soluble HAP (14.0 vs 6.3 and 15.3 vs 9.4, respectively). There was a tendency for the proportion of follicles which ovulated to be higher in the crude HAP group. The mean number of oocytes or the proportion of oocytes recovered was significantly higher (P < 0.05) in the crude HAP group than in the soluble HAP group. 相似文献
98.
ABSTRACT The present work investigates the relationships between nitrogen fixation, carbon metabolism and oxygen consumption by bacteroids of Mesorhizobium ciceri in root nodules of chick-pea plants. Its aim was to establish whether some of the compounds which accumulate under salt stress may be used as respiratory substrates by bacteroids to fuel their own metabolism and nitrogenase activity. Plants were grown in a growth chamber, and salt stress was induced by adding 50 mM NaCl to the nutrient solution at sowing. The data presented here show a rise in fermentative metabolism in nodules of chick-pea plants exposed to high salinity, and suggest that proline, lactate or ethanol, may play an important role as energy-yielding substrates for bacteroids in this plant species. The bacteroids could utilize glucose as a respiratory substrate both under control and saline conditions, while malate did not appear to be the preferred substrate in the presence of salt. 相似文献
99.
Venous (maternal) and cord blood (neonatal) samples of Omani women who had a daily supplement of Centrum Materna multivitamin and multimineral tablet throughout pregnancy were investigated at late preterm (n=37) and at term (n=37) delivery for erythrocyte indices, micromineral, antioxidant, and lipid values. Hemoglobin (Hb), hematocrit (HCT), mean cell volume (MCV), red cell distribution width (RDW), copper (Cu), zinc (Zn), ceruloplasmin, erythrocyte Cu-Zn superoxide dismutase (Cu-Zn SOD), cholesterol, apolipoprotein (apo) A-I and apo B were measured by appropriate analytical systems. Cu/zinc and Cu/ceruloplasmin ratios were calculated. The erythrocyte indices were normal in neonatal blood but showed borderline anemia in maternal blood of both groups. There were significantly decreased values of Cu (P=0.012), Zn (P=0.001), apo A-I (P=0.029), and Cu/ceruloplasmin ratio (P=0.032) in late preterm compared to term mothers. Significantly decreased values of Cu (P=0.003), ceruloplasmin (P<0.0001), apo A-I (P=0.024), and Cu/Zn ratio (P=007) were observed in late preterm relative to term neonates. Late preterm mothers were significantly younger (P=0.027) than term mothers. Maternal age correlated positively with apo A-I (r=0.424, P=0.012) and negatively with Cu/Zn ratio (r=-0.353, P=0.040). The findings suggest that with daily dietary Centrum Materna supplementation throughout pregnancy, hematological indices were maintained within normal in mothers and neonates, but the levels of microminerals and micromineral ratios were subnormal in late preterm mothers and their neonates. 相似文献
100.
In vitro regeneration and morphogenesis studies in common bean 总被引:1,自引:0,他引:1
Kingdom Kwapata Robab Sabzikar Mariam B. Sticklen James D. Kelly 《Plant Cell, Tissue and Organ Culture》2010,100(1):97-105
An efficient protocol for high frequency in vitro regeneration of multiple shoots and somatic embryos from the embryonic axis
of common bean (Phaseolus vulgaris) was developed. Ten common bean cultivars representing a wide range of diversity among current commercial market classes
were used for in vitro regeneration evaluation in our study. These cultivars were tested on 63 different media formulations
consisting of combinations of cytokinins, namely benzyladenine (BA) and thidiazuron (TDZ) at concentration levels of 0.0,
1.0, 2.5, 5.0 and 10.0 mg l−1 and auxin, namely naphthalene acetic acid (NAA) and indole-3-acetic acid (IAA) at concentration levels of 0.0, 0.05, 0.1
and 1.0 mg l−1. P. vulgaris cv. Olathe pinto bean performed the best producing over 20 multiple shoots per explant while cv. Condor black bean was the
poorest with nine multiple shoots per explant. The optimum media for regeneration of multiple shoots was 4.4 mg l−1 Murashige and Skoog (MS) containing 2.5 mg l−1 BA and 0.1 mg l−1 IAA supplemented with 30 mg l−1 silver nitrate. Adventitious shoots and somatic embryos were regenerated on 4.4 mg l−1 MS medium containing 1 mg l−1 TDZ and 0.05 mg l−1 NAA supplemented with 30 mg l−1 silver nitrate or activated charcoal. Efficient and effective rooting of plantlets was achieved by dipping the cut end base
of in vitro regenerated shoots in 1.0 mg l−1 indole-3-butyric acid (IBA) solution and culturing on media containing 4.4 mg l−1 MS supplemented by 0.1 mg l−1 IAA, NAA or IBA. 相似文献