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The authors tested whether perfectionism dimensions interact with specific stress to predict depression over time. A sample of 103 current and former patients completed measures of perfectionism and depression at Time 1 and measures of stress and depression 4 months later. After controlling Time 1 depression, self-oriented perfectionism interacted only with achievement stress to predict Time 2 depression. Socially prescribed perfectionism did not interact with achievement or social stress to predict Time 2 depression, but it did predict Time 2 depression as a main effect. The results provide support for the contention that perfectionism dimensions are involved in vulnerability to depression over time. 相似文献
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T Barberi P Klivenyi NY Calingasan H Lee H Kawamata K Loonam AL Perrier J Bruses ME Rubio N Topf V Tabar NL Harrison MF Beal MA Moore L Studer 《Canadian Metallurgical Quarterly》2003,21(10):1200-1207
Existing protocols for the neural differentiation of mouse embryonic stem (ES) cells require extended in vitro culture, yield variable differentiation results or are limited to the generation of selected neural subtypes. Here we provide a set of coculture conditions that allows rapid and efficient derivation of most central nervous system phenotypes. The fate of both fertilization- and nuclear transfer-derived ES (ntES) cells was directed selectively into neural stem cells, astrocytes, oligodendrocytes or neurons. Specific differentiation into gamma-aminobutyric acid (GABA), dopamine, serotonin or motor neurons was achieved by defining conditions to induce forebrain, midbrain, hindbrain and spinal cord identity. Neuronal function of ES cell-derived dopaminergic neurons was shown in vitro by electron microscopy, measurement of neurotransmitter release and intracellular recording. Furthermore, transplantation of ES and ntES cell-derived dopaminergic neurons corrected the phenotype of a mouse model of Parkinson disease, demonstrating an in vivo application of therapeutic cloning in neural disease. 相似文献
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D Dwuma-Badu JS Ayim NY Fiagbe AN Tackie JE Knapp DJ Slatkin PL Schiff 《Canadian Metallurgical Quarterly》1976,39(4):213-217
Dinklacorine was first isolated in 1974 from extracts of the roots of Tiliacora dinklagei Engl. (Menispermaceae) and designated TD-2. The ir, uv and mass spectra of dinklacorine were very similar to those of the dibenzodioxin biphenylalkaloid tiliacorine. However, the two alkaloids differed in their mp, specific rotation and nmr spectra. Methylation of dinklacorine with diazomethane afforded O-methyltiliacorine while treatment of dinklacorine with sodium methoxide and methyl iodide gave O-methyltiliacorine dimethiodide. However, prolonged treatment of tiliacorine and dinklacorine with diazoethane afforded different O-ethyl ethers. In addition, O-ethyldinklacorine dimethiodide and O-ethyltiliacorne dimethiodide were different. Furthermore, acetylation of the two alkaloids with acetic anhydride and puridine gave O-macetyl esters which were not identical. A considertation to these data and especially the mass spectral fragmentation patterns indicated dinklacorine to be a positional isomer of tiliacorine with the phenolic hydroxy group present in the biphenyl portion of the molecule on the opposite side to tiliacorine. Finally, a comparison of the cd spectra of dinklacorine and tiliacorine suggests that they have the same stereochemistry. 相似文献
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NY Kiang JM Rho CC Northrop MC Liberman DK Ryugo 《Canadian Metallurgical Quarterly》1982,217(4555):175-177
A horseradish peroxidase technique was used to trace the peripheral terminations of two types of ganglion cells in adult cats. It was found that large, usually bipolar ganglion cells end on inner hair cells and small, usually pseudomonopolar ganglion cells end on outer hair cells. Thus, a virtually complete segregation of afferent neural inputs from the two types of hair cells was directly confirmed. 相似文献
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NY. 《军民两用技术与产品》2014,(8)
正由中国第一重型机械集团公司承制的国产首台AP1000反应堆压力容器通过水压试验,实现了AP1000三代核电关键设备国产化的新突破,标志着我国企业已全面掌握三代核电AP1000核一级承压设备的关键制造技术,制造技术水平和质量管理能力达到美国西屋公司的验收标准,具备了三代核电关键设备批量化、产业化发展能力。 相似文献
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M. JOURDES G. PASQUIER M. FERMAUD L. GÉNY P. REY B. DONECHE P.‐L. TEISSEDRE 《Australian Journal of Grape and Wine Research》2012,18(2):215-226
Background and Aims: The impact of grey mould (Botrytis cinerea (B. cinerea)) was quantified on chemical, phenolic and sensory qualities of grapes, derived musts and wines. Methods and Results: Analyses were carried out by using naturally or artificially infected grape berries at ripeness or overripeness. In grape seeds, chemical analyses revealed no major differences between healthy and rotten grapes. In grape skins of Botrytis‐affected berries, concentrations of all the phenolic compounds (anthocyanins and proanthocyanidin monomers, dimers and trimer) decreased drastically. Mean degree of polymerization of the proanthocyanidin polymeric fraction was also affected in skins. Chemical analyses of musts and wines made with different percentages of rotten berries showed a moderate impact of the pathogen on their phenolic composition. Nevertheless, sensory analyses underlined a loss of wine sensory quality perceptible from a threshold as low as 5% of Botrytis‐affected grapes onwards. Conclusion: Phenolic variations and the associated negative impact in grapes, derived musts and wines may be related to oxidation phenomena from B. cinerea. The main effects of severity/age of grey mould and the level of berry maturity are also discussed. Significance of the Study: B. cinerea drastically affects the phenolic and organoleptic properties of grape skins and derived wines. Therefore, prophylactic actions early in the vineyard, evaluation of the sanitary status of the harvested grapes and berry sorting are primordial even under low disease pressure. 相似文献
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LC Agren L Ekman B L?wenadler JG Nedrud NY Lycke 《Canadian Metallurgical Quarterly》1999,162(4):2432-2440
The ADP-ribosylating enterotoxins, cholera toxin (CT) and Escherichia coli heat-labile toxin, are among the most powerful immunogens and adjuvants yet described. An innate problem, however, is their strong toxic effects, largely due to their promiscuous binding to all nucleated cells via their B subunits. Notwithstanding this, their exceptional immunomodulating ability is attracting increasing attention for use in systemic and mucosal vaccines. Whereas others have separated adjuvanticity from toxicity by disrupting the enzymatic activity of the A1 subunit by site-directed mutagenesis, we have constructed a nontoxic molecule that combines the full enzymatic activity of the A1 subunit with a B cell targeting moiety in a gene fusion protein, the CTA1-DD adjuvant. Despite its more selective binding properties, we found comparable adjuvant effects of the novel CTA1-DD adjuvant to that of CT. Here we unequivocally demonstrate, using a panel of mutant CTA1-DD molecules, that the immunomodulating ability of CTA1-DD is dependent on both an intact enzymatic activity and the Ig-binding ability of the DD dimer. Both agents, CT and CTA1-DD, ADP-ribosylate intact B cells. However, contrary to CT, no increase in intracellular cyclic AMP in the targeted cells was detected, suggesting that cyclic AMP may not be important for adjuvanticity. Most remarkably, CTA1-DD achieves similar immunomodulating effects to CT using a ganglioside-GM1 receptor-independent pathway for internalization. 相似文献
80.
The alphabeta-tubulin heterodimer has two high affinity guanosine 5'-triphosphate binding sites, so that purified tubulin usually contains two molecules of bound guanosine nucleotide. Half this nucleotide is freely exchangeable with exogenous guanine nucleotide, and its binding site has been readily localized to the beta-subunit. The remaining nonexchangeable guanosine 5'-triphosphate can only be released from tubulin by denaturing the protein. We replaced the exchangeable site nucleotide of tubulin with 2'-deoxyguanosine 5'-diphosphate, exposed the resulting tubulin to ultraviolet light, degraded the protein, and isolated ribose-containing peptide derived from the nonexchangeable site. A large cyanogen bromide peptide was recovered, and its further degradation with endoproteinase Glu-C established that cysteine-295 of alpha-tubulin was the major reactive amino acid cross-linked to guanosine by ultraviolet irradiation. 相似文献