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51.
Although not as effective as ABA, the triazoles S-3307 and triadimefon induced partial closure of stomata in isolated epidermal strips of Commelina benghalensis L. Both in the light and dark the stomatal closure induced by triazoles was reversed by GA and cytokinins, with GA being more effective. In an in vivo system using excised shoots, increasing triazole concentrations resulted in a proportional increase in stomatal diffusive resistance. Light was ineffective in reversing the triazole-induced stomatal closure both in vivo and in vitro, which indicates that the effects of triazoles are probably mediated through hormonal regulation rather than an effect on photochemical reactions.  相似文献   
52.
The major form of bovine erythrocyte carbonic anhydrase has been prepared by a new method in which the conventional chloroform-ethanol treatment is replaced by chromatography on DEAE-Sephadex. Single crystals, suitable for high resolution X-ray diffraction studies, have been obtained from enzyme prepared by this method. The space group is P6122. The unit cell contains 12 enzyme molecules and has the dimensions a = b = 68 A?, c = 244 A?.  相似文献   
53.
Two groups of patients with dementia of Alzheimer type were studied with respect to monoamine oxidase (MAO) activity. In one group of 11 patients MAO activity was determined in platelets and in the other group of 14 patients in the brain (hypothalamus, caudate nucleus, hippocampus and cortex gyrus cinguli) post mortem. The results were compared to controls matched for age and sex. Platelet MAO activity was significantly higher in patients with dementia of Alzheimer type compared to controls. Brain MAO-B activity but not MAO-A activity was significantly higher in the dementia group in hyppocampus and cortex gyrus cinguli. In the controls there were positive correlations for MAO-B activity with age in the four brain regions, but these correlations were absent in the dementia group. This could be explained by differences in age of onset of dementia and that the disease process does not develop homogeneously in different brains.  相似文献   
54.
Phyllody disease is a threat to sesame production in Kerman province, southeastern Iran. RFLP analysis of PCR products of phytoplasma-specific 16S rRNA gene (1.8 kb) and phylogenetic analyses of 16S-23S rDNA spacer region (SR) sequence indicated that the predominant agent associated with sesame phyllody in Kerman province is a phytoplasma with 100% similarity with eggplant big bud, and peanut witches’-broom phytoplasmas, members of “Candidatus Phytoplasma aurantifolia” from Iran and China, respectively. Among the samples tested, only one strain (SPhSr1), had a unique RFLP profile and its SR was 100% similar in nucleotide sequence with the phytoplasma carried by Orosius albicinctus and Helianthus annus witches’-broom phytoplasma from Iran, members of “Ca. Phytoplasma trifolii”. Virtual RFLP patterns of SPhJ2 (representative of the predominant PCR-RFLP profiles) SR sequence were identical to those of peanut witches’-broom phytoplasma (16SrII-A, JX871467). However, SPhSr1 SR sequence patterns resemble (99.7%) those of vinca virescence phytoplasma (16SrVI-A, AY500817).  相似文献   
55.
The extracellular carboxymethyl cellulase (CSCMCase) from the yeast, Cryptococcus sp. S-2, was produced when grown on cellobiose. It was purified to homogeneity from the supernatant by ultrafiltration, DEAE-5PW anion exchange column and TSK-Gel G3000SW gel filtration. The purified enzyme was monomeric protein with molecular mass of approximately 34 kDa. The optimum temperature and pH for the action of the enzyme were at 40–50 °C and 3.5, respectively. It was stable at pH range of 5.5–7.5 and retained approximately 50% of its maximum activity after incubating at 90 °C for 1 h. Moreover, it could able to hydrolyze carboxymethyl cellulose sodium salt higher than insoluble cellulose substrate such as Avicel, SIGMACELL® and CM cellulose. Due to its action at acidic pH and moderately stable at high temperature, the gene encoding carboxymethyl cellulase (CSCMCase) was isolated and improved the enzyme yield by high cell-density fermentation of Pichia pastoris. The CSCMCase cDNA contains 1023 nucleotides and encodes a 341-amino acid. It was successfully expressed under the control of alcohol oxidase I promoter using methanol induction of P. pastoris fermentation in a 2L ABLE bioreactor. The production of the recombinant carboxymethyl cellulases was higher than that from Cryptococcus sp. S-2 of 657-fold (2.75 and 4.2 × 10−3 mg protein L−1, respectively) indicating that the leader sequence of CSCMCase has been recognized and processed as efficiently by P. pastoris. Furthermore, the recombinant enzyme was purified in two-step of ultrafiltration and hydrophobic interaction chromatography which would be much more convenient for large-scale purification for successful industrial application.  相似文献   
56.
Genome size, karyotype structure, heterochromatin distribution, position and number of ribosomal genes, as well as the ITS2 sequence of the internal transcribed spacer (ITS) were analysed in silver fir (Abies alba Mill.). The analysis also included characterization of the Arabidopsis-type of telomeric repeats in silver fir and in related species. The results were compared with results from other species of the Pinaceae, to evaluate phylogeny and chromosomal and molecular evolution in the Pinaceae. Integrated chromosomal data provided insights into chromosome and karyotype evolution in the Pinaceae. The evolutionary trend for GC-rich heterochromatic blocks seems to involve loss of blocks that are not associated with rDNA. Similarly, numerous large blocks of interstitial plant telomeric repeats that are typical for all analysed species of the genus Pinus were not observed in the evolutionarily younger genera, such as Abies, Picea and Larix. On the contrary, the majority of telomeric sequences in these three genera appeared confined to the chromosome ends. We confirmed the current position of Abies and Tsuga in subfamily Abietoideae and the position of Pinus in the subfamily Pinoideae based on ITS2 sequences. Pseudotsuga is placed together with Larix into the subfamily Laricoideae. We conclude that the current position of the genus Picea in the subfamily Abietoideae should be reconsidered and, possibly, the genus Picea should be reclassified as a separate subfamily, Piceoideae, as recently proposed.  相似文献   
57.
The aim of this study was to explore the relationship between consumption of large doses of lactic acid bacteria (LAB) and the behaviour and brain morphobiochemistry of normal growing rats. Four groups of rats were treated with LAB cultures twice daily for 6 months. The control group received 1 ml of saline per treatment, while two experimental groups received 1 ml of living bacteria (Lactobacillus plantarum and Lactobacillus fermentum, respectively) and the remaining group received a heat-treated (inactivated) L. fermentum culture. After 2 and 6 months of treatment, respectively, eight animals from each group were sacrificed, and specimens were taken for further analyses. The behaviour of the rats was evaluated five times in an open-field test at monthly intervals throughout the study. Lactobacilli treatment for 2 months induced changes in the motoric behaviour of the rats. The concentration of the astrocytesoluble and filament glial fibrillary acidic protein (GFAP) decreased in the posterior part of the hemispheres, including the thalamus, hippocampus and cortex of the rats treated with L. fermentum. A greater decrease in filament GFAP (up to 50%) was shown in the group receiving the live form of L. fermentum. In contrast, the GFAP in the live L. plantarum-treated group increased, showing elevated levels of the soluble and filament forms of GFAP in the posterior part of the hemispheres.A 60–66% decrease in the amount of the astrocyte-specific Ca-binding protein S-100b was shown in the posterior parts of the hemispheres and in the hindbrain of rats given LAB for 2 months.Prolonged feeding with LAB for 4 months up to full adulthood led to a further decrease in astrocyte reaction, reflected as an additional decrease in the amount of soluble GFAP and locomotor activity in all experimental groups. The changes in filament GFAP and S-100b appeared to disappear after prolonged feeding (total of 6 months) with LAB.In summary, LAB dietary treatment affected the ontogenetic development of the astrocytes, with the highest intensity observed in the early stages of rat development. It can be postulated that LAB treatment may play a preventive role in neurological diseases by decreasing astrocyte reaction and, consequently, lowering locomotor activity.  相似文献   
58.
The effects of uniconazole (S-3307) application on the growth and cadmium (Cd) accumulation of accumulator plant Malachium aquaticum (L.) Fries. were studied through a pot experiment. The application of S-3307 increased the biomass and photosynthetic pigment content of M. aquaticum in Cd-contaminated soil, and also improved the superoxide dismutase (SOD) and peroxidase (POD) activities in M. aquaticum. Application of S-3307 increased Cd content in shoots and decreased Cd content in roots of M. aquaticum, but the translocation factor (TF) of M. aquaticum increased with the increase of S-3307 concentration. For phytoextraction, the application of S-3307 increased Cd extractions by roots, shoots and whole plants of M. aquaticum, and the maxima were obtained at 75 mg L?1 S-3307, which increased by 22.07%, 37.79% and 29.07%, respectively, compared with their respective controls. Therefore, S-3307 can be used for enhancing the Cd extraction ability of M. aquaticum, and 75 mg L?1 S-3307 was the optimal dose.  相似文献   
59.
目的:探讨醒脑静对颅脑损伤大鼠的保护作用及其机制。方法:健康雄性成年SD大鼠63只,随机分为3组(n=21):假手术组、模型组、醒脑静组。模型组与醒脑静组均采用自由落体撞击伤方法制作创伤性脑损伤模型,假手术组仅行开颅术,不造成脑损伤。醒脑静组盆大鼠造模后10min内经尾静脉注射醒脑静注射液10ml/(kg·d),模型组与假手术组则经尾静脉注射等量0.9%氯化钠溶液,三组均连续给药7d。给药第7天比较各组大鼠血清中S-100B蛋白和神经特异性烯醇化酶(NSE)水平,脑组织含水量,检测血清中超氧化物歧化酶(SOD)、丙二醛(MDA)和谷胱甘肽过氧化物酶(GSH—Px)含量,并对各组大鼠进行神经功能缺损评分。结果:与假手术组比较,醒脑静组和模型组均有明显的神经缺损,脑组织含水量、MDA、S-100B蛋白和NSE水平明显升高,SOD、GSH-Px含量明显降低;醒脑静组与模型组比较,醒脑静组神经缺损程度及脑含水量显著低于模型组,血清中MDA和NSE水平明显低于模型组,SOD、GSH-Px活性明显高于模型组。结论:醒脑静注射液对大鼠颅脑损伤具有保护作用,其作用机制可能与减轻颅脑损伤后脑水肿及抑制氧自由基反应、保护神经细胞有关。  相似文献   
60.
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