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1.
A novel experimental method was developed which allows the determination of the threshold concentration of sucrose by use of a linear sucrose gradient in water. With this method a continuous tasting of the test-liquid is possible. A panel of 15 persons experienced in taste-testing was used. Three gradients of different steepness were applied: 0 to 1.5% (w/w) sucrose in 2 min (I), 3 min (II) and 4 min (III). The results of the new method were compared with those of the standard method (DIN). With gradients I and II we found values which were significantly higher than those of the standard method (I: 0.49% (w/w); II: 0.46% (w/w); DIN: 0.31% (w/w)), whereas with gradient III the same threshold value was found as with the DIN-Method (III: 0.32% (w/w)).  相似文献   
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Flight muscles of male moth, B. mori seem to utilize carbohydrate preferentially as a source of energy for all its acrobatic movements during the search for female moth. Depletion of triacylglycerol from flight muscles without affecting its level from fat body suggests that this lipid fraction serves as a source of energy in flight muscles during insemination processes. Significant depletion of triacylglycerol and glycogen from flight muscles of female moth after egg laying indicates that they are used to meet the energy requirement of female during oviposition activity. Depletion of proteins from flight muscles of male and female insects suggest that these proteins are transported to the accessory reproductive glands to meet their protein demand.  相似文献   
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Background  

The aim of this study was to evaluate long-term platinum retention in patients treated with cisplatin and oxaliplatin.  相似文献   
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Russian Journal of Bioorganic Chemistry - A series of novel quinoline-benzoxazolinone ester hybrids were synthesized characterized and assessed for their in vitro anti-inflammatory and...  相似文献   
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A highly chitinolytic strain Penicillium ochrochloron MTCC 517 was procured from MTCC, Chandigarh, India. Culture medium supplemented with 1% chitin was found to be suitable for maximum production of chitinase. Purification of extracellular chitinase was done from the culture medium by organic solvent precipitation and DEAE-cellulose column chromatography. The chitinase was purified 6.92-fold with 29.9% yield. Molecular mass of purified chitinase was found to be 64 kDa by SDS-PAGE. The chitinase showed optimum temperature 40 °C and pH 7.0. The enzyme activity was completely inhibited by Hg2+, Zn2+, K+ and NH4+. The enzyme kinetic study of purified chitinase revealed the following characteristics, such as apparent Km 1.3 mg ml?1, Vmax 5.523 × 10?5 moles l?1 min?1 and Kcat 2.37 s?1 and catalytic efficiency 1.82 s?1 M?1. The enzyme hydrolyzed colloidal chitin, glycol chitin, chitosan, glycol chitosan, N,N′-diacetylchitobiose, p-nitrophenyl N-acetyl-β-d-glucosaminide and 4-methylumbelliferyl N-acetyl-β-d-glucosaminide. The chitinase of P. ochrochloron MTCC 517 is an exoenzyme, which gives N-acetylglucosamine as the main hydrolyzate after hydrolysis of colloidal chitin. Protoplasts with high regeneration capacity were obtained from Aspergillus niger using chitinase from P. ochrochloron MTCC 517. Since it also showed antifungal activity, P. ochrochloron MTCC 517 seems to be a promising biocontrol agent.  相似文献   
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In an attempt to improve the physicochemical properties of cefixime (CEF), its supramolecular inclusion compounds were prepared with β-cyclodextrin (βCD) and hydroxypropyl-β-cyclodextrin (HPβCD) in presence and/or absence of ternary component l-arginine (ARG) using spray drying technique. Initially, the phase solubility studies revealed a stoichiometry of 1:1 molar ratio with an AL-type of phase solubility curve. The stability constants of binary systems were remarkably improved in presence of ARG, indicating positive effect of its addition. The inclusion complexes were characterized by FTIR, XRPD, DSC, SEM, particle size analysis, and dissolution studies. Further, molecular mechanic (MM) calculations were performed to investigate the possible orientations of CEF inside βCD cavity in presence and/or absence of ternary component. In case of physicochemical studies, the ternary systems performed well as a result of comprehensive effect of ternary complexation and particle size reduction achieved by a spray drying technology.  相似文献   
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Human cells utilize a variety of complex DNA repair mechanisms in order to combat constant mutagenic and cytotoxic threats from both exogenous and endogenous sources. The RecQ family of DNA helicases, which includes Bloom helicase (BLM), plays an important function in DNA repair by unwinding complementary strands of duplex DNA as well as atypical DNA structures such as Holliday junctions. Mutations of the BLM gene can result in Bloom syndrome, an autosomal recessive disorder associated with cancer predisposition. BLM-deficient cells exhibit increased sensitivity to DNA damaging agents indicating that a selective BLM inhibitor could be useful in potentiating the anticancer activity of these agents. In this work, we describe the medicinal chemistry optimization of the hit molecule following a quantitative high-throughput screen of >355,000 compounds. These efforts lead to the identification of ML216 and related analogs, which possess potent BLM inhibition and exhibit selectivity over related helicases. Moreover, these compounds demonstrated cellular activity by inducing sister chromatid exchanges, a hallmark of Bloom syndrome.  相似文献   
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RationaleLower respiratory tract illness (LRTI) frequently causes adult hospitalization and antibiotic overuse. Procalcitonin (PCT) treatment algorithms have been used successfully in Europe to safely reduce antibiotic use for LRTI but have not been adopted in the United States. We recently performed a feasibility study for a randomized clinical trial (RCT) of PCT and viral testing to guide therapy for non-pneumonic LRTI.ObjectiveThe primary objective of the current study was to understand factors influencing PCT algorithm adherence during the RCT and evaluate factors influencing provider antibiotic prescribing practices for LRTI.ResultsDiagnosis of pneumonia on admission was the only variable significantly associated with non-adherence [7% (adherence) vs. 26% (nonadherence), p = 0.01]. Surveys confirmed possible infiltrate on chest radiograph as important for provider decisions, as were severity of illness, positive sputum culture, abnormal CBC and fever. However, age, patient expectations and medical-legal concerns were also at least somewhat important to prescribing practices. Physician agreement with the importance of viral and PCT testing increased from 42% to 64% (p = 0.007) and 49% to 74% (p = 0.001), respectively, after the study.ConclusionsOptimal algorithm adherence will be important for definitive PCT intervention trials in the US to determine if PCT guided algorithms result in better outcomes than reliance on traditional clinical variables. Factors influencing treatment decisions such as patient age, presence of fever, patient expectations and medical legal concerns may be amenable to education to improve PCT algorithm compliance for LRTI.  相似文献   
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