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671.
Chiral triamine antimalarial compounds have been identified following the screening of mixture-based positional scanning libraries made up of 31,320 compounds against P. falciparum. The library, namely N-methyl triamine (TPI 762) was generated following exhaustive reduction of resin-bound acylated dipeptides. Using the PSCL approach, individual compounds were rapidly identified which were only 10 times less active than the standard drugs chloroquine (CQ) and Artemisinin (Artes).  相似文献   
672.
Determination of the taxonomic position of microorganisms associated with diatoms was carried out using microscopic, microbiological, and phylogenetic methods. Examination of the cultures of the fresh-water diatom Synedra acus grown in Lake Baikal water by epifluorescence and electron microscopy revealed that bacterial cells colonized the mucilage surrounding the cells of living microalgae and their cell surfaces and penetrate into the frustules of dead diatoms. A total of 13 strains of heterotrophic bacteria were isolated in pure cultures and described. Based on the results of analysis of their morphological, physiological, and biochemical properties, as well as on data obtained by 16S rRNA gene analysis, the following strains were identified to the species level: Sphingomonas sp., Variovorax paradoxus, Pseudomonas fluorescens, Microbacterium trichothecenolyticum, Rhodococcus sp., Caulobacter vibrioides, and Brevundimonas vesicularis.  相似文献   
673.
ABSTRACT: INTRODUCTION: High-voltage electrical injuries are uncommonly reported and may predispose to both immediate and delayed neurologic complications. CASE PRESENTATION: We report the case of a 43-year-old Caucasian man who experienced a high-voltage electrocution injury resulting in ischemic myelopathy and secondary paraparesis. CONCLUSION: High-voltage electrocution injuries are a serious problem with potential for both immediate and delayed neurologic sequelae. The existing literature regarding effective treatment of neurologic complications is limited. Long-term follow-up and multidisciplinary management of these patients is required.  相似文献   
674.
Summary We tested the effect of Bisantrene (BS) and Theprubicin (THP-ADR) on cell growth of a human pancreatic carcinoma cell line (MIA PaCa-2). After 1 h exposure ID50 of BS or THP-ADR was 3×10−7 and 5×10−8 M, respectively. Increasing the exposure time from 1 h to continuous exposure for 5d resulted in 11-fold decrease in ID50 for BS and a 6-fold decrease for THP-ADR. Both drugs inhibited [14C]thymidine incorporation to the same extent and caused an accumulation of cells into G2+M phase of the cell cycle. This work is supported by a gift, from Mr. Issam Fares and U.S. Public Health Service Grants AM 07114 and CA 19182.  相似文献   
675.
676.
Summary For mycological fat production,Aspergillus nidulans andPenicillium lilacinum were grown on media made up of crushed and boiled sweet potatoes. Mycelial mats containing a fair amount of fat were obtained, namely, 15 % in case ofAspergillus and 24 % in case ofPenicillium. Media containing an external supply of glucose gave rise to increase in percentage fat in mycelium, but the amount of mycelium and consequently the total fat content decreased.Addition of sodium nitrate gave heavier mycelial mats but the total fat content could not be raised.Addition of potassium phosphate or magnesium sulphate or both to the sweet potato medium gave rise to heavier mycelial mats but with lower fat content.  相似文献   
677.
Formalin-fixed sections of rat intestine were treated in a solution of 0.5% periodic acid in 50% aqueous phosphoric acid for the concurrent demonstration of 1,2-glycols and DNA. The effects of varying the concentration of reagents, time of exposure and temperature on the results showed that, at 28°C, good reactions were obtained in 10-15 min when the concentration of the phosphoric was between 40 and 60% and that of the periodic acid between 0.05 and 0.50%.  相似文献   
678.
β1,4-galactosyltransferase is unusual among the glycosyltransferases in that it is found in two subcellular compartments where it performs two distinct functions. In the trans-Golgi complex, galactosyltransferase participates in oligosaccharide biosynthesis, as do the other glycosyltransferases. On the cell surface, however, galactosyltransferase associates with the cytoskeleton and functions as a receptor for extracellular oligosaccharide ligands. Although we now know much regarding galactosyltransferase function in these two compartments, little is known about how it is targeted to these different sites. By cloning the galactosyltransferase gene products, certain features of the protein have been identified that may be critical for its expression on the cell surface or retention within the Golgi complex. This article discusses recent studies which suggest that a cytoplasmic sequence unique to one galactosyltransferase isoform is required for targeting a portion of this protein to the plasma membrane, enabling it to function as a cell adhesion molecule. These findings allow one to manipulate surface galactosyltransferase expression, either positively or negatively, and perturb galactosyltransferase-dependent cellular interactions during fertilization and development.  相似文献   
679.
A modification of Gomori's method for alkaline phosphatase was applied to 5-7 mm cubes of fresh, unfixed human skin. Exposure to the substrate of buffered Na-β·glycerophosphate was varied from 8-36 hr, to the 2% Co(NO3)3, 2-12 hr; and to ammonium sulfide (containing approximately 1% NH3), 1-2 hr. Optimum timing for these treatments were found to be 24, 4 and 1 hr, respectively. After staining, blocks were embedded in paraffin and serial sections were made. In such small blocks, the staining was uniform throughout the block. Alkaline phosphatase activity was seen in the walls of the subepidermal and periappendageal capillaries, as well as in the eccrine sweat glands, and did not differ from that seen in stained frozen sections. In particular, there was no loss of specificity and no diffusion of the enzyme.  相似文献   
680.
Zusammenfassung Der Stoffwechsel von 32P-Dipterex wurde in Aspergillus niger, Penicillium notatum und Fusarium sp. untersucht. Als hydrophile Metaboliten sind mindestens zwei Verbindungen nachweisbar. Die eine wurde als 1-Oxy-2,2,2-Trichloräthyl-Phosphonsäure-Monomethylester identifiziert und stellte 30–44% der Gesamtmetaboliten dar. Die zweite wurde als 1-Oxy-2,2,2-Trichloräthyl-Phosphonsäure angesehen.
Summary The metabolism of 32P-Dipterex in Aspergillus niger, Penicillium notatum and Fusarium sp. has been investigated. At least two hydrolytic metabolites could be detected. One compound was identified as O-methyl-2,2,2-trichloro-1-hydroxyethyl phosphonic acid, and contributed to 30–44% of the total metabolites output. The second compound is believed to be 2,2,2-trichloro-1-hydroxyethyl phosphonic acid.
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