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著: 《生物信息学》2019,26(5):8-12
随着全球建造业向数字化全面转型,建筑信息模型(BIM)的教学将是未来几年风景园林设计与实施的重要主题。介绍了风景园林专业BIM的教学方法和数字化竖向设计及其应用在BIM场地设计项目中的重要性。数字化竖向设计是实现BIM的途径。风景园林教育必须在其教学中讲解BIM建模方法和过程。  相似文献   
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Substituted N-Cbz and N-Boc protected arylamino acrylic acids and esters have been prepared and used in asymmetric hydrogenations catalyzed by PROPRAPHOSRh. Stereoselectivities > 90% ee could be achieved, the rate of which is dependent on the position of the substituent in the aromatic ring. The N-Boc derivatives provide advantages compared with the N-Cbz analogues. The amino acid derivatives were fully characterized by 19F, 13C, and 1H NMR spectroscopy. © 1996 Wiley-Liss, Inc.  相似文献   
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The aims of this study were to (i) evaluate the prevalence and the incidence of hepatitis C virus (HCV) infection in hemodialysis patients in two different centers in S?o Paulo (Brazil), (ii) determine the time required to detect HCV infection among these patients by serology or PCR, (iii) establish the importance of alanine aminotransferase determination as a marker of HCV infection, and (iv) identify the HCV genotypes in this population. Serum samples were collected monthly for 1 year from 281 patients admitted to hospital for hemodialysis. Out of 281 patients, 41 patients (14.6%) were HCV positive; six patients seroconverted during this study (incidence = 3.1/1000 person-month). In 1.8% (5/281) of cases, RNA was detected before the appearance of antibodies (up to 5 months), and in 1.1% (3/281) of cases, RNA was the unique marker of HCV infection. The genotypes found were 1a, 1b, 3a, and 4a. The presence of genotype 4a is noteworthy, since it is a rare genotype in Brazil. These data pointed out the high prevalence and incidence of HCV infection at hemodialysis centers in Brazil and showed that routine PCR is fundamental for improving the detection of HCV carriers among patients undergoing hemodialysis.  相似文献   
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All vertebrates depend on neural circuits to produce propulsive movements; however, the contribution of individual neural cell types to control such movements are not well understood. We report that zebrafish space cadet mutant larvae fail to initiate fast turning movements properly, and we show that this motor phenotype correlates with axonal defects in a small population of commissural hindbrain neurons, which we identify as spiral fiber neurons. Moreover, we demonstrate that severing spiral fiber axons produces space cadet-like locomotor defects, thereby providing compelling evidence that the space cadet gene plays an essential role in integrating these neurons into the circuitry that modulates fast turning movements. Finally, we show that axonal defects are restricted to a small set of commissural trajectories, including retinal ganglion cell axons and spiral fiber axons, and that the space cadet gene functions in axonal pathfinding. Together, our results provide a rare example in vertebrates of an individual neuronal cell type that contributes to the expression of a defined motor behavior. Movies available on-line  相似文献   
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En route to their targets, motor axons encounter choice points at which they select their future path. Experimental studies predict that at each choice point specialized cells provide local guidance to pathfinding motor axons, however, the identity of these cells and their signals is unknown. Here, we identify the zebrafish unplugged gene as a key component for choice point navigation of pioneering motor axons. We show that in unplugged mutant embryos, motor neuron growth cones reach the choice point but make inappropriate pathway decisions. Analysis of chimeric embryos demonstrates that unplugged activity is produced by a selective group of mesodermal cells located adjacent to the choice point. As the first motor growth cones approach the choice point, these mesodermal cells migrate away, suggesting that unplugged activity influences growth cones by a contact-independent mechanism. These data suggest that unplugged defines a somite-derived signal that elicits differential guidance decisions in motor growth cones.  相似文献   
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The osmotic and ion-specific components of salt-induced inhibition of leaf expansion growth were investigated in beans grown from 12 h to several days in either NaCl-containing solution cultures, an isosmotic concentrated macronutrient solution, or a vermiculite–compost mixture with low Na+ but high Cl availability. Inhibition of leaf expansion and leaf ABA increase was more intense in the NaCl than in the isosmotic macronutrient treatment. Root Na+ was highly correlated to inhibition of leaf expansion and leaf or xylem sap ABA. When Na+ was sequestered in soil, salinized plants showed no reduction in leaf expansion or ABA increase, regardless of the presence of high leaf Cl concentrations. Stomatal conductance exhibited an exponential relationship with the reciprocal value of xylem sap ABA. Our results indicate that an ion-specific effect caused by Na+ in roots may account for an ABA-mediated reponse of both stomatal closure and leaf expansion inhibition.  相似文献   
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The objective of the present study was to explore the site of synthesis of vitellogenin (Vtg) in fresh water edible crab, Oziothelphusa senex senex. Vtg cDNA fragments were isolated from the hepatopancreas of female crabs using RT-PCR method, and the deduced amino acid sequence of O. senex senex showed more than 60% identity with other brachyuran Vtg sequences. RT-PCR analysis showed that Vtg mRNA can be detected only in hepatopancreas of female Oziothelphusa but not in other tissues including eyestalks, Y-organs, mandibular organs, thoracic ganglion, hypodermis and ovary. Antibodies were raised against vitellin purified from the ovary of O. senex senex. Immunoprecipitation analysis revealed the presence of Vtg in the hepatopancreas of vitellogenic stage I females and in the hemolymph, hepatopancreas and ovary extracts from vitellogenic stage II females but absent in hemolymph and hepatopancreas extract of males. These results suggest that Vtg is synthesized only in hepatopancreas but not in the ovaries of O. senex senex. In addition, Vtg synthesized in hepatopancreas is transported to ovary through hemolymph.  相似文献   
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