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151.
The conditions for separation, identification and quantitative determination of epimers 22R and 22S of budesonide by capillary gas chromatography (GC) with FID detection and two various sample injection methods, namely split-splitless and cool on-column, were established. In analysis helium as carrier gas and Rtx-5 capillary column of 7 m in length along with stationary phase Crossbond 5% diphenyl-95% dimethyl polysiloxane were used. The individual epimers were identified under specified conditions by using standard samples of different declared concentration of each epimer under investigation: (1) 51.2% of epimer 22R and 47.3% of epimer 22S, and (2) 95.1% of 22R and 4.4% of 22S, as well as Pulmicort, a preparation containing micronized budesonide as an active substance. It seems that good parameters of preliminary validation achieved by the proposed methods can confirm its suitability for quantitative analysis purpose. The retention times obtained for epimers 22R and 22S, depending on injection technique are about 7.7 and. 8.3 min for split and, approx. 10.3 and 10.9 min for cool on-column. The limits of detection and quantitation are 5.7 and 6.2 ng, for 22R respectively, and 4.3 and 4.8 ng for 22S. The linearity is maintained for concentrations ranging from 0.01 to 0.20 mg/ml. The quantitative analysis features of repeatability, high precision and accuracy confirmed by the obtained results and its statistical evaluation.  相似文献   
152.
153.
Recently published biochemical data suggest the significant role of selenium compounds as the adjuvants combined with L: -thyroxine therapy, which can reduce antithyroid peroxidase antibodies' (TPOAb) levels in patients with Hashimoto disease. The study was undertaken to document in a more detailed way the changes in parameters expressing the thyroid and ovarian function brought about by selenium supplementation (50-100 microg/day) in a woman undergoing autoimmune thyroiditis (AIT) therapy. This prospective observational case study lasted for 14 months plus additional 5 months as a follow-up period. Parameters reflecting selenium status, thyroid metabolism, and sex hormones secretion were determined at the onset and end of the study period, as well as in some of its middle points. During the supplementation trial, serum selenium (Se) increased by 45% and plasma glutathione peroxidase (GPX3) by 21%. TPOAb decreased by 76%. All other parameters also fluctuated during the supplementation period, but all results were always within normal physiological ranges. After withdrawal of the supplementation, the sharp fall of Se and GPX3 promptly occurred, and this phenomenon was accompanied with a marked increase in TPOAb. This report stresses the importance of selenium supplementation in AIT treatment. However, the efficiency and durability of the effect of Se supplementation on the TPOAb titer remain an open question. The clarification of mechanism(s) underlying Se interaction with autoimmune processes should throw new light on this issue.  相似文献   
154.
The quality of wheat depends on a large complex of genes and environmental factors. The objective of this study was to identify quantitative trait loci controlling technological quality traits and their stability across environments, and to assess the impact of interaction between alleles at loci Glu-1 and Glu-3 on grain quality. DH lines were evaluated in field experiments over a period of 4 years, and genotyped using simple sequence repeat markers. Lines were analysed for grain yield (GY), thousand grain weight (TGW), protein content (PC), starch content (SC), wet gluten content (WG), Zeleny sedimentation value (ZS), alveograph parameter W (APW), hectolitre weight (HW), and grain hardness (GH). A number of QTLs for these traits were identified in all chromosome groups. The Glu-D1 locus influenced TGW, PC, SC, WG, ZS, APW, GH, while locus Glu-B1 affected only PC, ZS, and WG. Most important marker-trait associations were found on chromosomes 1D and 5D. Significant effects of interaction between Glu-1 and Glu-3 loci on technological properties were recorded, and in all types of this interaction positive effects of Glu-D1 locus on grain quality were observed, whereas effects of Glu-B1 locus depended on alleles at Glu-3 loci. Effects of Glu-A3 and Glu-D3 loci per se were not significant, while their interaction with alleles present at other loci encoding HMW and LMW were important. These results indicate that selection of wheat genotypes with predicted good bread-making properties should be based on the allelic composition both in Glu-1 and Glu-3 loci, and confirm the predominant effect of Glu-D1d allele on technological properties of wheat grains.  相似文献   
155.
Summary The plasma membrane of Paramecium aurelia is covered with a ruthenium red stainable surface coat. Results obtained after digestion with pronase, trypsin and neuraminidase suggest the glycoprotein nature of this structure. Lipid extraction also affects the surface coat forming material. The results are consistent with the model proposed by Ginsburg and Kobata dealing with spatial configuration of the surface coat components.Authors are grateful to Mrs. D. Kucharczyk for very efficient technical assistence, to Mrs. Z. Kaminska for sectioning the material and Mr. A. Renski for help with the electron microscope service.  相似文献   
156.
During the last decades, the critically endangered Hooded Vulture Necrosyrtes monachus has strongly declined across its African range. Although direct persecution has been suggested as a major cause of this decline, little is known about the impact of humans on reproductive output in West Africa. We studied the impact of human activities on the reproductive output of Hooded Vultures in the Garango area of Burkina Faso. Twenty and 56 nesting attempts were monitored, respectively, during the breeding season in 2013/14 and 2014/15, to determine reproductive success and identify causes of nest failure. Annual breeding success varied between 0.68 and 0.71 chicks fledged per breeding pair per year and productivity was assessed at 0.57 chicks fledged per territorial pair in 2014/15. The main threats imposed by humans were poaching of eggs, chicks and collection of nest materials, leading to 20% (13 out of 64 breeding attempts) of nest failures over the two years. An additional important reason for nest failure was the pruning and (partial) cutting of nest trees. Despite this high level of human interference, we found that Hooded Vulture nest success increased with proximity to human settlements, probably because breeding vultures benefit from protection by people against persecution and disturbance.  相似文献   
157.
158.
Hairy root cultures of Lithospermum canescens were established using three strains of Agrobacterium rhizogenes: ATCC 15834, LBA 9402 and NCIB 8196. Eight lines resulting from infection with A. rhizogenes ATCC 15834 demonstrated sufficient biomass increase and were submitted to further investigations. The contents of acetylshikonin (ACS) and isobutyrylshikonin (IBS) in transformed hairy roots made up ca. 10% of those observed in natural roots of L. canescens (24.35 and 14.48 mg g−1 DW, respectively). One line, Lc1-D, produced the largest amounts of ACS (2.72 mg g−1 DW) and IBS (0.307 mg g−1 DW). Traces of pyrrolizidine alkaloids (PA), canescine and canescenine, were found in all lines of transformed hairy roots.  相似文献   
159.
The simplified AFLP method was developed and evaluated for identification and genetic diversity studies of wheat cultivars. Selective primers exploited in AFLP assay based on a single cutting enzyme PstI ((PstI)AFLP) generated total of 111 robust fragments, including 67 (60%) monomorphic and 12 (11%) cultivar-specific markers. Average similarity between 15 cultivars was 0.650, and varied from 0.293 ('Hope' vs. 'Aurora') to 0.865 ('Norman' vs. 'Hornet'). Mean similarities within groups of winter wheat cultivars with and without 1BL/1RS chromosome were 0.713 and 0.685, respectively. A higher variation was found in the group of spring wheats: 0.677. The obtained results confirm the usefulness of the proposed modification of the AFLP technique for diversity studies and identification of common wheat cultivars.  相似文献   
160.
The presence and pattern of coexistence of some biologically active substances in nerve fibres supplying the mammary gland in the immature pig were studied using immunohistochemical methods. The substances studied included: protein gene product 9.5 (PGP), tyrosine hydroxylase (TH), somatostatin (SOM), neuropeptide Y (NPY), galanin (GAL), calcitonin gene-related peptide (CGRP) and substance P (SP). The mammary gland was found to be richly supplied by PGP-immunoreactive (PGP-IR) nerve fibres that surrounded blood vessels, bundles of smooth muscle cells and lactiferous ducts. The vast majority of these nerves also displayed immunoreactivity to TH. Immunoreactivity to SOM was observed in a moderate number of nerve fibres which were associated with smooth muscles of the nipple and blood vessels. Immunoreactivity to NPY occurred in many nerve fibres associated with blood vessels and in single nerves supplying smooth muscle cells. Solitary GAL-IR axons supplied mostly blood vessels. Many CGRP-IR nerve fibres were associated with both blood vessels and smooth muscles. SP-IR nerve fibres richly supplied blood vessels only. The colocalization study revealed that SOM, NPY and GAL partly colocalized with TH in nerve fibres supplying the porcine mammary gland.  相似文献   
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