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461.
462.
Dehydration of D-galacto-2-heptulose phenylosazone with methanolic sulfuric acid afforded two 3,6-anhydro-osazone derivatives (2 and 3). Compound 2 was obtained as the preponderant isomer, without inversion at C-1 (C-3 of the starting osazone), and 3 was obtained with inversion. The anomeric configurations of 2 and 3 were determined by n.m.r. spectroscopy. Refluxing of 2 and 3 with copper sulfate afforded two C-nucleoside analogs, namely, 4-β- and 4-α- D-lyxofuranosyl-2-phenyl-1,2,3-triazole, 4 and 5, respectively. The anomeric configurations of 4 and 5 were determined by n.m.r and c.d. spectroscopy. Acetylation of 4 and 5 afforded the tri-O-acetyl derivatives. The mass spectra of these compounds were discussed.  相似文献   
463.
Pigment‐dispersing factor (PDF) is an important neurotransmitter in insect circadian systems. In the cricket Gryllus bimaculatus, it affects nocturnal activity, the free‐running period and photic entrainment. In this study, to investigate whether these effects of PDF occur through a circadian molecular machinery, we measured mRNA levels of clock genes period (per) and timeless (tim) in crickets with pdf expression knocked‐down by pdf RNAi. The pdf RNAi decreased per and tim mRNA levels during the night to reduce the amplitude of their oscillation. The phase of the rhythm advanced by about 4 h in terms of trough and/or peak phases. On the other hand, pdf mRNA levels were little affected by per and tim RNAi treatment. These results suggest that PDF affects the circadian rhythm at least in part through the circadian molecular oscillation while the circadian clock has little effect on the pdf expression.  相似文献   
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Molecular Biology Reports - Autism spectrum disorder (ASD) is an increasing concern among the Iraqi Arab population. The genetic alterations that cause ASD are likely to converge at the synapse....  相似文献   
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Molecular and Cellular Biochemistry - Head and neck squamous cell carcinoma (HNSCC) is a prevalent malignancy with a poor prognosis, whose biomarkers have not been studied in great detail. We have...  相似文献   
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Summary When analytical reagent grade chemicals were used in the preparation of the fermentation medium for citric acid production, enrichment with zinc was found to be essential for establishing, good acid production addition of manganese on the other hand, was found to be inhibitory. Slight inhibition or no effect was obtained on addition of copper and iron respectively.A Greeting to the 70th Birthday of Prof. Dr. A. Rippel-Baldes.  相似文献   
470.
The aim of the present work is to apply a non-invasive test, using thumb fingerprint residue analysis, for detection of beta-thalassemia (β-Thal). The relative percentages of free amino acids (AA) in the latent fingerprint of β-Thal patients and healthy subjects were compared. The sample included 24 β-Thal patient and 24 healthy subjects, aged 5–10 years old. Twenty-three AA plus ammonia were analyzed by a sensitive high-performance liquid chromatographic method with fluorescence detection. The profile of AA was calculated based on the percentage of relative amount of each AA to serine (Ser) as it found to be the predominant peak. The statistical and chromatographic profiles of β-Thal patients were characterized by significant decrease of ornithine, lysine, and zero tyrosine, with significant increase of ammonia, and proline. Other amino acids that exist in low ratios were estimated statistically for significance changes. The relative percentages of each AA of healthy subjects were approximately constant. For this reason, these mentioned AA were assigned as major fingerprint markers of β-Thal.  相似文献   
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