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LN Kazakova 《Canadian Metallurgical Quarterly》1997,16(4):144-145
Therapeutical efficacy of laferon (J2-interferon) was in children of preschool and school ages with acute respiratory viral infections. Endonasal employment of the drug during 3 days of acute period of the illness significantly decreases the duration of the period of catarrh and intoxication, being accompanied by positive immunological reactions on the part of T-cellular immunity and immunoglobulin synthesis. 相似文献
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AV Pugaev NS Bogomolova VV Bagdasarov KB Sirozhitdinov LN Vinogradova 《Canadian Metallurgical Quarterly》1997,(3):123-125
Pharmacokinetics was studied of kefsole administered by intravenous and endolymphatic routes to patients (n = 23) with acute pancreatitis. The studies made showed that intravenous route for the drug administration makes for a quicker entering of the antibiotic into the peritoneal exudate. Apart from these reasons, endolymphatic antibacterial therapy does not appear to avert the development of complications involving pus-formation/discharging in acute pancreatitis and does not seem to be essential in the complex of therapeutic measures to be applied for treating the above patients. 相似文献
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Ultra-wideband (UWB) is a booming technology in the field of wireless communication. This paper presents a brief idea related to the various coherent and non-coherent IR-UWB detectors. Due to the limitation in transmit power spectral density of UWB system, the major challenges faced by UWB system includes, achieving Quality of Service, system performance and coverage area. So, the combination of UWB system with cooperative communication will not only improve the system performance, but also help in expanding coverage area of signals. A brief review of the work done by various researchers in the field of cooperative impulse radio (IR) UWB communication is also presented in this paper. The working principle and performance analysis of the various coherent and non-coherent IR-UWB detectors using cooperative relay strategies are also discussed at large in this paper. The various fixed cooperative relay strategies used for cooperative UWB communication is Amplify and Forward, Decode and Forward and Detect and Forward. From the simulation results it can be inferred that, even though IR-UWB DTR receiver gives a much better BER performance than IR-UWB ED receiver using both cooperative and non-cooperative strategies, yet ED receiver is preferred because of its less complexity and low power consumption. Future prospects in the field of cooperative IR-UWB communication have also been discussed in this paper. 相似文献
47.
Facile one-step transfer process of graphene 总被引:1,自引:0,他引:1
Chemical vapour deposition (CVD) is emerging as a popular method for growing large-area graphene on metal substrates. For transferring graphene to other substrates the technique generally used involves deposition of a polymer support with subsequent etching of the metal substrate. Here we report a simpler one-step transfer process. Few-layer graphene (FLG) grown on a Cu substrate were transferred to a silanized wafer by just pressing them together. Hydrogen bonding between the hydroxyl group on FLG and the amine group on silane molecules facilitate the transfer. 相似文献
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BACKGROUND: The prognosis of patients with brain metastasis as the only manifestation of an undetected primary tumor generally is considered to be poor. Therefore, most treatment is palliative. The authors reviewed the clinical outcomes and treatment results of patients presenting with brain metastasis from an undetected primary tumor at The University of Texas M. D. Anderson Cancer Center. METHODS: Between 1977-1996, 220 patients were referred to the study department for the treatment of brain metastasis from an undetected primary tumor. The patients' records were reviewed to identify those for whom brain metastasis was the only manifestation of the primary tumor. The majority of patients were excluded from the current analysis because extracranial metastasis also were present. Thirty-nine patients qualified for this retrospective review. The level of neurosurgical excision varied, but all patients received radiotherapy. Tumor control in the brain and survival were analyzed by various tumor-related and treatment-related factors. RESULTS: In 31 patients, the brain metastasis were adenocarcinomas, whereas the remaining patients had tumors of various other histologies. In 12 patients, the primary tumor eventually was found, most commonly in the lung. The median survival time for all patients was 13.4 months. Overall survival rates (OS) at 1, 3, and 5 years were 56%, 19%, and 15%, respectively. Intracranial disease control was 72% at 5 years. Patients who received gross total resection (GTR) and radiotherapy had significantly better OS than patients who received radiotherapy alone. The OS of patients whose primary tumor was identified was similar to that of patients in whom the primary tumor remained occult. CONCLUSIONS: Brain metastasis as the only manifestation of an unknown primary tumor is a distinct clinical entity. The prognosis for patients with this presentation is better than that of patients with brain metastasis in general. Although the majority of patients die of extracranial disease, a few will achieve long term survival. Treatment to the brain is effective in controlling local disease; aggressive treatment with GTR and radiotherapy is recommended. 相似文献
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LS Parentoni EC de Faria MJ Bartelega VM Moda AC Facin LN Castilho 《Canadian Metallurgical Quarterly》1998,274(1):105-109
Pentachlorophenol (PCP) and molybdate have been shown to inhibit the sulfoconjugation of various chemicals in rats and therefore are useful to examine the role of sulfoconjugation on the toxicity of a chemical. PCP inhibits sulfation by competing with substrates for phenol-sulfotransferases, but not hydroxysteroid-sulfotransferases. In contrast, molybdate decreases sulfation by limiting sulfate availability and thereby decreasing the synthesis of 3'-phosphoadenosine 5'-phosphosulfate (PAPS), which is the obligate cosubstrate for sulfation. Therefore, it was of interest to determine whether PCP or molybdate is effective in decreasing the in vivo sulfation of dehydroepiandrosterone (DHEA), which is a substrate for hydroxysteroid-sulfotransferases. PCP (40 micromol/kg ip) or molybdate (7.5 mmol/kg po) was given 45 min and 4 h, respectively, prior to the start of DHEA infusion. The effects of these two sulfation inhibitors on DHEA sulfation were dependent on the rate of DHEA infusion in rats. PCP had different effects on the sulfation of various infusion rates of DHEA in rats. PCP had little effect on the sulfation after the two lowest infusion rates of DHEA (12.5 and 25 mg/kg) and actually increased (233%) DHEA-sulfate serum concentrations with the highest DHEA infusion rate (50 mg/kg). Although molybdate had little affect on the sulfation of the lowest DHEA infusion rate, it significantly decreased (50-85%) DHEA-sulfate serum concentrations with the two higher DHEA infusion rates. These data indicate that molybdate, unlike PCP, decreases the sulfation of DHEA and may be a useful tool to decrease the sulfation of other substrates of hydroxysteroid-sulfotransferases. 相似文献
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