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91.
We analyzed the association between kisspeptin and plasma adipokines (leptin and adiponectin) in normal-weight and over-weight young females. Thirty young Saudi females, based on their body mass index (BMI), were divided into two groups (15 students/group) as (1) Normal weight (NW): BMI = 18.5–24.99 and (2) Over-weight/obese (OW): BMI ≥ 25. Serum adipokines (leptin, adiponectin) and kisspeptin levels were measured in early follicular, pre-ovulatory, and luteal phase in both groups with ELISA. Menstrual cycle phases were confirmed by serum estradiol levels. There was no association of kisspeptin with leptin in early follicular (r ?0.34, P 0.31), pre-ovulatory (r ?0.32, P 0.34) and luteal phase (r 0.21, P 0.54). Likewise, kisspeptin was not found to be correlated with adiponectin in early follicular (r 0.41, P 0.21), pre ovulatory (r 0.24, P 0.48), and luteal phase (r 0.40, P 0.23) when values recorded during different time points during the cycle were plotted with each other.  相似文献   
92.
Journal of Plant Growth Regulation - Salinity stress hampers rice growth and development due to its osmotic, ionic, and hormonal (ethylene) stresses. High ethylene production affects inferior and...  相似文献   
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Isolates of Salmonella enteritidis PT3, a rare phage type, were recovered from patients and strains were isolated from an outbreak of gastroenteritis that occurred during the summer of 1997 in North-East Sardinia, Italy. To investigate possible clonal involvement in the outbreak and to evaluate the capacity to discriminate among S. enteritidis PT3 strains, a number of molecular typing methods including ribotyping with a mixture of PstI and SphI (PS-ribotyping), PFGE with endonuclease XbaI and RAPD typing with four arbitrary primers was used. The typical XbaI endonuclease generated PFGE pattern also explained the prevalence of highly clonal S. enteritidis PT3 strains in the outbreak and adjacent areas. RAPD fingerprinting with primers OPA 4, OPB 15, OPB17 and P1254 exhibited a single but unique RAPD profile among the outbreak strains from various sources that differed significantly from control strains. The results of this study showed that when an appropriately chosen set of primers is employed, RAPD fingerprinting can be used as an alternative, rapid, highly reproducible technique for tracing the clonal relations of S. enteritidis PT3, and can be more discriminatory than PFGE. Furthermore, this study revealed the possibility of PT3 causing outbreak.  相似文献   
95.
The lifetime of different microsomal steroidogenic enzymes and the cytochrome components of the NADPH-cytochrome P-450 pathway have been determined in rat testis by measuring their decrease logarithmically after hypophysectomy. Although both cytochrome P-450 and 17α-hydroxylase show biphasic decay curves, the first decay curve contains 89–94% of the cytochrome P-450 and 17α-hydroxylase levels. Steroidogenic enzymes which are located mainly in the leydig cells, decay much faster than microsomal protein, t12 = 12 days, which represents mainly decay of tubular protein. The similarity between the major half-life of cytochrome P-450, t12 = 3.3 days, 17α-hydroxylase, t12 = 2.3 days and the C17–C20 lyase, t12 = 3.4 days and the uniformity of their response to human chorionic gonadotrophin (HCG) provides additional evidence that these two steroidogenic enzymes require cytochrome P-450. Both the 17α-hydroxylase and the C17–C20 lyase were shown to have a constant activity per nmole of cytochrome P-450 during a sixfold change in the level of cytochrome P-450 brought about by HCG treatment of rats with intact pituitaries. The decay of 17β-hydroxysteroid dehydrogenase, t12 = 4.5 days, was slower than P-450 dependent enzymes. Rats with intact pituitaries are not under maximal stimulation by endogenous LH because addition of HCG increases the levels of microsomal and mitochondrial cytochrome P-450 220 and 1620%, respectively. The rates of synthesis during the increase from one cytochrome P-450 level to another was calculated at 0.1182 testes/day for microsomal cytochrome P-450 and 0.10 nmoles/2 testes/day for mitochondrial cytochrome P-450. Treatment of hypophysectomized rats with HCG results in large increases of cytochrome P-450, 17α-hydroxylase, C17–C20 lyase and 5α-reductase, but not cytochrome b5, microsomal protein, 7α-hydroxylase, or the 17β-hydroxysteroid dehydrogenase. While it is clear that the two cytochrome P-450 dependent hydroxylases involved in steroidogenesis and the 5α-reductase are under the control of gonadotrophin, it is not clear how 17β-hydroxysteroid dehydrogenase levels are maintained or in what manner the 5α-reductase level is controlled in mature animals.  相似文献   
96.
Pomegranate (Punica granatum L.) is one of the oldest known edible fruits. It has grown in popularity and is a profitable fruit crop due to its attractive features including a bright red appearance and its biological activities. Scientific exploration of the genetics and evolution of these beneficial traits has been hampered by limited genomic information. In this study, we sequenced the complete chloroplast (cp) genome of the native P. granatum (cultivar Helow) cultivated in the mountains of Jabal Al-Akhdar, Oman. The results revealed a P. granatum cp genome length of 158,630 bp, characterized by a relatively conserved structure containing 2 inverted repeat regions of 25,466 bp, an 18,686 bp small single copy regions, and an 89,015 bp large single copy region. The 86 protein-coding genes included 37 transfer RNA genes and 8 ribosomal RNA genes. Comparison of the P. granatum whole cp genome with seven Lagerstroemia species revealed an overall high degree of sequence similarity with divergence among intergenic spacers. The location, distribution, and divergence of repeat sequences and shared genes of the Punica and Lagerstroemia species were highly similar. Analyses of nucleotide substitution, insertion/deletions, and highly variable regions in these cp genomes identified potential plastid markers for taxonomic and phylogenetic studies in Myrtales. A phylogenetic study of the cp genomes and 76 shared coding regions generated similar cladograms. The complete cp genome of P. granatum will aid in taxonomical studies of the family Lythraceae.  相似文献   
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We present here the first detailed kinetic analysis of the dissociation reaction of amyloid protofibrils by utilizing pressure as an accelerator of the reaction. The experiment is carried out on an excessively diluted typical protofibril solution formed from an intrinsically denatured disulfide-deficient variant of hen lysozyme with Trp fluorescence as the reporter in the pressure range 3-400 MPa. From the analysis of the time-dependent fluorescence decay and the length distribution of the protofibrils measured on atomic force microscopy, we conclude that the protofibril grows or decays by attachment or detachment of a monomer at one end of the protofibril with a monomer dissociation rate independent of the length of the fibril. Furthermore, we find that the dissociation reaction is strongly dependent on pressure, characterized with a negative activation volume DeltaV(odouble dagger) = -50.5 +/- 1.60 ml mol(-1) at 0.1 MPa and with a negative activation compressibility Deltakappa(double dagger) = -0.013 +/- 0.001 ml mol(-1) bar(-1) or -0.9 x 10(-6) ml g(-1) bar(-1). These results indicate that the protofibril is a highly compressible high-volume state, but that it becomes less compressible and less voluminous in the transition state, most probably due to partial hydration of the existing voids. The system eventually reaches the lowest-volume state with full hydration of the monomer in the dissociated state.  相似文献   
100.
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