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991.
Uremic optic neuropathy (UON) is extremely rare, although sporadic cases have been reported. UON is sometimes regarded as a manifestation of uremic neuropathy. Here, we report a case of end-stage renal disease presenting as UON. A 22-year-old male was transferred to our nephrology department due to azotemia. Sudden deterioration of his vision occurred 3 days before his transfer. The patient's blood pressure was 150/90 mmHg, and he had no symptoms or signs of uremia, except for the visual disturbance. Blood tests showed an elevated serum creatinine of 6.0 mg/dL and serum BUN of 53.6 mg/dL. Both kidneys were decreased in size on ultrasound. His best-corrected vision was 20/62.5 in both the eyes. Ophthalmoscopy revealed hyperemia, swelling of both optic nerve heads, and blurred margins of both optic disks. These findings are compatible with UON. The patient's visual acuity and visual field improved following hemodialysis and corticosteroid treatment. The swelling of the patient's optic disks was also resolved. The patient is currently undergoing hemodialysis with the goal of vision restoration. Uremic optic neuropathy should be considered when patients with advanced chronic kidney disease complain of deterioration of their vision.  相似文献   
992.
In an attempt to produce additional alkylation and crosslinking in the minor groove of DNA, imidazole-containing analogs of distamycin were synthesized with benzoic acid mustard (BAM) and methoxyaziridinyl moieties present at the N- and C-termini, respectively. Analogs 1a-c differed in the number of methylene units (2-4 respectively) between the C-terminal carbonyl group and the methoxyaziridinyl moiety. DNA binding affinity to several polynucleotides decreased with increasing linker length, whereas DNA interstrand crosslinking ability, as measured by a plasmid gel based assay, increased. The in vitro cytotoxicity in human chronic myeloid leukemia K562 cells and the panel of human tumor cell lines at the National Cancer Institute decreased with increasing number of methylene units, and no increase in cytotoxicity was observed over compound AR-1-122 which did not contain the methoxyaziridinyl moiety. 1a-c had the same sequence selectivity of alkylation as AR-1-122, showing alkylation only at 5'-TTTTGPu sequences. The relative binding to these sequences decreased with increasing number of methylene units. The addition of a methoxyaziridinyl moiety in this group of imidazole and BAM-containing compounds can, therefore, increase crosslinking ability to naked DNA but this does not result in an increase in cytotoxicity. In contrast the cytotoxicity was related to their ability to produce sequence specific alkylation at 5'-TTTTGPu sequences.  相似文献   
993.
The use of industrial waste [mill scale (MS), red mud (RM), Al-dross (AD)] as fluxing agents in the sulfurization of Fe-Ni-Cu-Co alloy to matte (Fe-Ni-Cu-Co-S) by carbothermic reduction of CaSO4 was investigated at 1673 K (1400 °C). The sulfurization efficiency (SE) was 76 (± 2) pct at RM or AD single fluxing. However, SE drastically increased to approximately 89 pct at a ‘5AD + 5MS’ combination, which was equivalent to reagent-grade chemical ‘5Al2O3 + 5Fe2O3’ fluxing (SE = 88 pct). The present results can be used to improve the cost-effective recovery of rare metals (Ni and Co) from deep sea manganese nodules.  相似文献   
994.
Peer-to-Peer Networking and Applications - Production scheduling is an important research topic widely studied during past few decades. However, many manufacturers still fail to successfully deploy...  相似文献   
995.
It was for the first time that of the fifth year of monitoring of Plantago lanceolata L., reproduced within the thirty-kilometer zone of Chernobyl NPP disaster, the authors discovered high incidence of seedlings with various morphological abnormalities. It is suggested that the damages observed are related to the cumulative effect of radiation.  相似文献   
996.
The adsorption of cadmium ions on granular activated carbon treated with nitric acid (NGAC), and untreated regular granulated activated carbon (RGAC) is reported in the absence and presence of mixtures of anionic (sodium dodecyl sulfate, SDS) and nonionic (Triton X-100, TX100) surfactants. In the absence of surfactants, NGAC adsorbed 8.7 times more Cd (0.165 mmol/g) than did RGAC (0.019 mmol/g). In RGAC suspensions, the amount of Cd sorbed increased significantly with increasing dose of SDS, to a maximum of 0.112 mmol/g. This increase was due to increased binding of Cd with sorbed SDS. However, in NGAC suspension, the amount of Cd sorbed was not increased further by the addition of SDS. It suggested that addition of SDS blocked the availability of surface functional groups in the microporous structure of NGAC.  相似文献   
997.
Films of aluminium oxide have been formed on single crystal silicon substrates using AlCl3-CO2-H2 gas mixtures in a cold-walled chemical vapour deposition (CVD) reactor. The nucleation and subsequent growth of the deposit have been observed under the varying process parameters. It is found that the nucleation and growth of the Al2O3 are dependent on the H2O flux and H2O supersaturation. An activation energy of 34.8 Kcal mol–1 is obtained for the growth rate indicating that the CVD of Al2O3 on silicon is a thermally activated process and limited by surface reaction. Scanning electron micrographs (SEM) show that the deposited films are amorphous at low temperature, 850° C, but change to fine grained polycrystalline structure at high temperature, 1000° C.  相似文献   
998.
The role of glutathione-S-transferase (GST) in alkylator drug resistance has been studied in MatB rat mammary carcinoma cells. A series of GST transfectant cell lines was established by using an expression vector containing the complementary DNA for the rat GST Yc gene under regulation of the SV40 early region promoter and the antibiotic resistance plasmid pSV2neo. Transfectant cell lines expressing up to 4-fold higher total GST activity than in the parental wild type cell line were identified. Southern blot analysis confirmed a DNA fragment corresponding in size to the transfected GST Yc complementary DNA. Wild type MatB cells contain very low levels of Yc protein, whereas the Yc+ clones showed greatly increased amounts of the Yc subunit. The effect of increased GST Yc activity on the sensitivity of the transfected clones to various cytotoxic agents was assessed by using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide cell survival assay. The clones expressing recombinant GST Yc were more resistant to melphalan (6- to 12-fold), mechlorethamine (10- to 16-fold), and chlorambucil (7- to 30-fold). In late passage populations of the GST Yc+ clones that had been grown over a period of 14 months under continuous selection in G418, GST activity was decreased and it was paralleled by a decrease in Yc protein. These late passage clones with diminished GST Yc content also demonstrate a partial reversion toward the wild type phenotype as determined by cytotoxicity assays using melphalan, mustargen, and chlorambucil. Interstrand DNA cross-links induced by mechlorethamine were significantly lower at 0, 2, and 20 h posttreatment in one of the GST Yc+ clones when compared to wild type MatB cells. These studies indicate that GST Yc overexpression can confer resistance to alkylating agents and that this correlates with inhibition of DNA cross-link formation.  相似文献   
999.
To enable remote collaboration among knowledge workers, there has been extensive research about prototyping network-based multiparty collaboration environments. Particularly, it is necessary to solve the configuration difficulties that arise from different settings of various tools in traditional room-based collaboration systems. To ease these difficulties, in this paper, we design a service composition oriented framework for the SMeet (Smart Meeting Space) multiparty collaboration environments by following the SOA (service oriented architecture) design principles. The proposed framework aims to facilitate the flexible configuration of diverse networked devices and associated application tools for successful multiparty collaboration. According to a pre-defined template, it helps the operators and users to compose services that are dispersed across remote sites. By leveraging open-source agent middleware, we also develop a SMeet toolkit with GUIs (graphical user interfaces) to assist the easily-configurable realization of SMeet multiparty collaboration environments. The developed SMeet toolkit is utilized to realize a remote collaboration scenario between two SMeet prototype sites, by enabling the network-based interactive sharing of HD-quality media on networked tiled displays (NeTDs).  相似文献   
1000.
    
In this paper, we propose a personally customizable content authoring service (C2Channel) using an Internet Protocol television (IPTV) platform, in which a user terminal such as a PC or set‐top box sends various kinds of multimedia files from a camera or camcorder to a remotely located authoring server (C2Channel server). The C2Channel server creates personalized content in real time by combining special effects with the multimedia files transmitted from the user terminal and then retransmits them to a predefined relevant service group as a personal IPTV channel through an IPTV network provider. This content authoring service supplies an automatic multimedia editing/composition service and offers unicast, multicast, and groupcast services for a large number of interested groups via an IPTV‐based real‐time media delivery platform (Open Live IPTV Engine [OLIVE]), in which a service management server is used for user identification through the IPTV personal channel. Because this platform uses a remote server resource when authoring personally customizable content, resources remaining at the user's terminal can be variously utilized. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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