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The synthesis of a cyclic heptapeptide, delavayin-C, cyclo(gly-tyr-tyr-tyr-pro-val-pro) is described. The structure of this compound was established on the basis of analytical IR, (1)H NMR and FAB mass spectral data. The antibacterial and antifungal activities of this peptide are also described.  相似文献   
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A patient of MELAS is reported. A 28-year-old woman was admitted to Shimada Municipal Hospital because of nausea, vomiting, and right homonymous hemianopsia. She had past history of dizziness and convulsion. A brain magnetic resonance imaging showed an ischemic lesion in the left occipital lobe, which disappeared in the follow-up study. Laboratory examination indicated elevated lactate and pyruvate levels in both blood and cerebrospinal fluid. The muscle biopsy demonstrated ragged-red fibers and strongly SDH-reactive blood vessels. PCR-RFLP analysis of DNA extracted from her muscle and blood as well as her mother's blood revealed a T to C mutation at nucleophile position of 3271 in mitochondrial DNA. She was diagnosed as having MELAS and discharged. One year after the first admission, she re-visited our hospital because of three days' duration of fatigability and generalized muscle pain after alcohol intake. She had severe lactic acidosis, rhabdomyolysis and acute renal failure. Despite a continuous hemodialysis and other intensive efforts, the patient died 20 hours later. Alcohol intake has been reported to induce rhabdomyolysis in myopathy with mitochondrial DNA deletions. The course of this patient suggests that alcohol intake can be an aggravating factor also in MELAS.  相似文献   
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Layered double hydroxides (LDHs) have drawn significant interest as emerging active materials for advanced energy storage devices; however, their low electric and ionic conductivity limit their applications. In this study, we report sulfur (S) and phosphorus (P) co-doped NiCo LDH nanoarrays prepared via a facile phosphor–sulfurization process to impart diverse co-doping effects. Combining the benefits of their unique hierarchical structure and reduced charge transfer resistance, the S and P co-doped NiCo LDH (NiCo LDH-SP) nanoarrays realize faster and more efficient redox reactions and achieve enhanced surface reactivity, thereby resulting in a performance superior to that of pristine NiCo LDH. Therefore, a NiCo LDH-SP shows an ultra-high specific capacitance of 3844.8 F g−1 at a current density of 3 A g−1 and maintains a specific capacitance of 2538.8 F g−1 at a high current density of 20 A g−1. Additionally, an asymmetric supercapacitor, assembled with the NiCo LDH-SP as the cathode and activated carbon (AC) as the anode (NiCo LDH-SP//AC), shows a high energy density of 74.5 W h kg−1 at a power density of 0.8 kW kg−1 and outstanding cycling stability, thereby retaining ∼81.3% of its initial specific capacitance after 5000 cycles. This study presents a facile and promising strategy for developing LDH-based electrode materials with excellent electrochemical performance for advanced energy storage applications.

The optimized sulfur and phosphorus co-doped NiCo LDH reduces charge transfer resistance and realizes efficient redox reaction, achieving an outstanding specific capacitance of 3844.8 F g−1 at 3 A g−1.  相似文献   
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A rapid and highly sensitive method for the determination of acamprosate (ACM), in human plasma using ESI-LC-MS/MS (electrospray ionization liquid chromatography tandem mass spectrometry) in negative ionization polarity in multiple reactions monitoring (MRM) mode was developed and validated. The procedure involves a simple protein precipitation step. Chromatographic separation was carried out on a Hypersil BDS C(18) column (150 mm × 4.6 mm, 5 μm) with an isocratic mobile phase and a total run time of 2.5 min. The standard calibration curves were linear within the range of 7.04-702.20 ng/mL for ACM (r ≥ 0.990). This study briefly describes the role of ion source design on matrix effects. ACM shows matrix effects in z-spray ionization source design, whereas it has no matrix effects in orthogonal spray ion source design. This method was successfully applied to a pharmacokinetic study after oral administration of acamprosate 333 mg tablet in Indian healthy male volunteers.  相似文献   
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