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1.
Development of Junction Elements from Study of the Bionics   总被引:1,自引:0,他引:1  
The applications of bionic methodology developed by the Laboratory of Design and Material Selection as basis in the creation of junction elements were demonstrated. These elements favor the application of Ecodesign in reference to the effec-tiveness of product dismount aiming the reduction of ambient impact in all its phases of use. The creation,the development and the confection of new junction elements were described,and case studies of new products developed specifically with this purpose were presented.  相似文献   

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Study of embryo rescue in floribunda rose   总被引:3,自引:0,他引:3  
In the past few decades, breeders have faced a lot of problems in rose improvement due to low sexual reproduction and poor germination because of embryo abortion. Immature embryos may be recovered in vitro. An efficient protocol for embryo rescue in two floribunda roses (Arunima and Shocking Blue) was developed. The germination of immature embryos was achieved by manipulating the growth media, growth hormones and culture conditions. The embryos (rescued) germinated and grew considerably on Murashige and Skoog basal medium supplemented with 2.5 mg ll BA (6-benzylaminopurine), 0.5 mg ll GA3 (gibberellic acid) and 3 (w/v) sucrose under 16-h photoperiod. A higher rate of germination was observed in cultures incubated 2 weeks in dark and subsequently transferred to 2 weeks in light at 16-h photoperiod. The embryo derived plantlets were successfully transferred to greenhouse and produced flowers. Embryo rescue technique in floribunda roses has great potential in floriculture industry.  相似文献   

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Background

Huntington’s disease patients have a number of peripheral manifestations suggestive of metabolic and endocrine abnormalities. We, therefore, investigated a number of metabolic factors in a 24-hour study of Huntington’s disease gene carriers (premanifest and moderate stage II/III) and controls.

Methods

Control (n = 15), premanifest (n = 14) and stage II/III (n = 13) participants were studied with blood sampling over a 24-hour period. A battery of clinical tests including neurological rating and function scales were performed. Visceral and subcutaneous adipose distribution was measured using magnetic resonance imaging. We quantified fasting baseline concentrations of glucose, insulin, cholesterol, triglycerides, lipoprotein (a), fatty acids, amino acids, lactate and osteokines. Leptin and ghrelin were quantified in fasting samples and after a standardised meal. We assessed glucose, insulin, growth hormone and cortisol concentrations during a prolonged oral glucose tolerance test.

Results

We found no highly significant differences in carbohydrate, protein or lipid metabolism markers between healthy controls, premanifest and stage II/III Huntington’s disease subjects. For some markers (osteoprotegerin, tyrosine, lysine, phenylalanine and arginine) there is a suggestion (p values between 0.02 and 0.05) that levels are higher in patients with premanifest HD, but not moderate HD. However, given the large number of statistical tests performed interpretation of these findings must be cautious.

Conclusions

Contrary to previous studies that showed altered levels of metabolic markers in patients with Huntington’s disease, our study did not demonstrate convincing evidence of abnormalities in any of the markers examined. Our analyses were restricted to Huntington’s disease patients not taking neuroleptics, anti-depressants or other medication affecting metabolic pathways. Even with the modest sample sizes studied, the lack of highly significant results, despite many being tested, suggests that the majority of these markers do not differ markedly by disease status.  相似文献   

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Twenty patients, five males and fifteen females, who had rubella arthritis were observed for periods ranging from one to ten years after recovery.Rubella arthritis in these patients was characterized by polyarthritis associated with fibrositis, myalgia, paresthesias and muscular weakness. All of the male patients but only one-third of the females had involvement of the knee joints. The small joints of the hands were the joints most commonly affected in women. Post-rubella arthritis rheumatic symptoms, especially fibrositis, persisted for many months in almost half of the females, not at all in the males.The leukocyte content of the blood tended to be low and the erythrocyte sedimentation rate accelerated in the few patients in which determinations were done.Latex tests were performed in 17 patients. Ten of the 17 were studied with the three-stage technique of Hall. Results of inhibition tests were positive in 80 per cent of the patients with rubella arthritis studied who were tested within 18 months after the onset of illness. None of the patients tested 18 months or more after rubella arthritis had positive reaction.  相似文献   

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The thermal denaturation of almond β-glucosidase [EC 3.2.1.21] was studied by differential scanning calorimetry. The shape of the DSC trace was highly dependent on pH; two peaks were observed between pH 6–8, but only one peak between pH 4–5. All of the DSC curves were resolved into three components according to the model of independent two-state processes, and the thermodynamic parameters for the denaturation were evaluated. The dependence of the shape of DSC curves was accounted for mainly by the rapid changes of denaturation enthalpy and denaturation temperature of the third component in the acidic pH region.  相似文献   

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With bacteriophage phi29 of Bacillus subtilis 133, suppressor-sensitive (sus) hydroxylamine mutants have been isolated. Intracistronic and intercistronic quantitative complementation placed the mutants in 13 cistrons, and three-factor crosses have been used to assign an unambiguous order for 10 cistrons. Recombination frequencies have been presented for several regions of the genome to facilitate comparison of the sus system with the previously published temperature-sensitive mapping systems.  相似文献   

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Binary vectors were constructed by fusing 0.4, 0.8, 1.6, and 2.9 kb 5' flanking regions of GBSS gene with GUS (β-glucuronidase). Transient GUS expression was observed in in vitro tuber slices bombarded with 0.8 kb GBSS-GUS construct. These constructs were then transferred into potato ( Solanum tuberosum L. cv. Desiree) via Agrobacterium tumefaciens transformation. Transgenic potato plants were confmned by X-Gluc staining and PCR. Using in vitro tuberization system, GUS expressions were assayed with fluorescence, it was shown that 0.8, 1.6 and 2.9 kb GBSS-GUS expressions were higher than 0.4 kb GBSS-GUS. 1.6 and 2.9 kb GBSS-GUS expressions were about 2 to 10-folds higher in tubers than in stems. In cultured shoots, GBSS-GUS expression could be induced by increased sucrose concentration but inhibited by light.  相似文献   

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The aim of the present work was to improve the solubility and dissolution profile of Irbesartan (IRB), a poorly water-soluble drug by formation of inclusion complex with β-cyclodextrin (βCD). Phase solubility studies revealed increase in solubility of the drug upon cyclodextrin addition, showing AL—type of graph with slope less than one indicating formation of 1:1 stoichiometry inclusion complex. The stability constant (K s) was found to be 104.39 M−1. IRB–βCD binary systems were prepared by cogrinding, kneading using alcohol, kneading using aqueous alcohol, and coevaporation methods. Characterization of the binary systems were carried out by differential scanning calorimetry, Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction, and proton nuclear magnetic resonance. The dissolution profiles of inclusion complexes were determined and compared with those of IRB alone and physical mixture. Among the various methods, coevaporation was the best in which the solubility was increased and dissolution rate of the drug was the highest. The study indicated the usefulness of cyclodextrin technology to overcome the solubility problem of IRB.  相似文献   

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1. DNA labelled with (14)C in the purine residues was prepared by treating newborn rats with [(14)C]formate and killing them for preparation of nucleic acids at 11-17 months. This DNA was incubated with N-methyl-N'-nitro-N-nitrosoguanidine, and then analysed for products of methylation and deamination reactions. 2. Evidence was found for the formation of 7-methylguanine and a smaller amount of 3-methyladenine, and, after preliminary denaturation of the DNA, 1-methyladenine was detected. The presence of cysteine increased the extent of methylation. No evidence was found for the formation of xanthine or hypoxanthine, even at pH5.5.  相似文献   

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Microencapsulation of ethanol extract of tea was performed in this study. In order to microencapsulate, β-cyclodextrin was used as wall material. Ethanol extract of tea was used as the core material. Microcapsules in the solid form were obtained by drying the emulsions. RSM showed that optimal processing parameters were as followings: core material/wall material 1/4, β-cyclodextrin content 16%, stirring time 30 min and stirring temperature 200 °C. Pharmacological activities of β-cyclodextrin encapsulation tea extract were determined. It was found that β-cyclodextrin encapsulation tea extract could enhance BMD, BMC and bone Ca, Zn and Cu contents. In addition, β-cyclodextrin encapsulation tea extract could still reduce blood Ca contents. These results indicated that β-cyclodextrin encapsulation tea extract was useful for improving bone quality in aged animals.  相似文献   

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Systems biology is a new and rapidly developing research area in which,by quantitativelydescribing the interaction among all the individual components of a cell,a systems-level understanding of abiological response can be achieved.Therefore,it requires high-throughput measurement technologies forbiological molecules,such as genomic and proteomic approaches for DNA/RNA and protein,respectively.Recently,a new concept,lipidomics,which utilizes the mass spectrometry(MS)method for lipid analysis,has been proposed.Using this lipidomic approach,the effects of N-methyl-N'-nitro-N-nitrosoguanidine(MNNG)on sphingomyelin metabolism,a major class of sphingolipids,were evaluated.Sphingomyelin moleculeswere extracted from cells and analyzed by matrix-assisted laser desorption ionization-time of flight MS.Itwas found that MNNG induced profound changes in sphingomyelin metabolism,including the appearance ofsome new sphingomyelin species and the disappearance of some others,and the concentrations of severalsphmgomyelin species also changed.This was accompanied by the redistribution of acid sphingomyelinase(ASM),a key player in sphingomyelin metabolism.On the other hand,imipramine,an inhibitor of ASM,caused the accumulation of sphingomyelin.It also prevented some of the effects of MNNG,as well as theredistribution of ASM.Taken together,these data suggested that the lipidomic approach is highly effectivefor the systematic analysis of cellular lipids metabolism.  相似文献   

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We compared the performances of the candidate loci for moss DNA barcoding and the primers used in amplifying the loci. Primers for three coded loci (matK, rps4 and rbcL a) and four non coded loci (atpB rbcL, atpF H, psbK I and trnH psbA) of the chloroplast genome, one from the mitochondrial genome (nad5), and one from the nucleus genome (ITS2) were evaluated. Seventy four samples representing 14 species belonging to five genera of Trachypodoaceae (or Meteoriaceae) were screened. All primers for matK and a pair of primers for trnH psbA failed. Low successes were encountered with the primers for atpF H and psbK I. The primers for psbK I produced several bands and the PCR products of atpF H were difficult to sequence. The powers of the remaining six loci were compared using the variability, identification success and the resolutions. It was found that ITS2 is the most promising candidate for DNA barcoding for mosses. Among the chloroplast genes, atpB rbcL exhibited the highest resolution. Although trnH psbA is very variable, it is too short to be an ideal barcode alone. Combinations of chloroplast genes were also tried and Ps of both atpB rbcL+trnH psbA and rbcL a++trnH psbA were 64% using NJ method. More additions of loci did not increase the resolution. No barcoding gap exists for all these loci. Phylogenetic analyses were carried out prior to the DNA barcoding evaluation and some taxonomic problems do exist. This study exemplifies the necessity of correct species delimitation and the adoption of both plastid and nuclear loci in plant DNA barcoding.  相似文献   

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