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991.
JL Boes PH Bland TE Weymouth LE Quint FL Bookstein CR Meyer 《Canadian Metallurgical Quarterly》1994,29(3):281-286
This review discusses the development and use of 5-hydroxytryptamine3 (5-HT3) antagonists, especially granisetron, for the treatment of chemotherapy-induced emesis. Following recent evidence suggesting that high-dose chemotherapy is more effective in increasing tumor response rate and median survival time, more effective antiemetic control is essential. Granisetron, a new 5-HT3, is approximately 400 times more potent than metoclopramide and, unlike metoclopramide, does not produce extrapyramidal side effects. Granisetron has been shown to be effective as a single prophylactic dose, over 5 days and in patients receiving repeated cycles of chemotherapy. Patients with nausea and vomiting within the first 24 h after chemotherapy are more likely to experience delayed symptoms; however, episodes of breakthrough nausea and vomiting can be controlled by intervention with one, and in some cases more, doses of granisetron. The development of granisetron represents an important advance in the control of chemotherapy induced emesis. 相似文献
992.
993.
Esmail M. A. Mokheimer Nabil M. Abd El-Aziz Hossam Eldin Mohamed Amin Mohamed Ibrahim Salem 《国际能源研究杂志》2003,27(12):1117-1130
This article presents a numerical simulation that estimates the freezing time for different products. In this regard, the freezing process is mathematically modelled by transient heat conduction equations that incorporate the physical properties of the three distinct regions that exist during a freezing process. These regions are namely, the solid phase region, the liquid phase region and the interface region. This model is experimentally validated and used to estimate the freezing time for three different food products, which are namely, fish balls, cherry juice and peas balls. The freezing times estimated numerically through the present model agree well with those reported in the literature and are in excellent agreement with the experimental data. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
994.
995.
Magnesium possesses numerous salutary effects for the treatment of acute myocardial infarction (AMI). It is a coronary vasodilator, calcium antagonist, afterload reducer, antiarrhythmic, and antiplatelet drug that modulates autonomic function and limits reperfusion injury when administered early in infarction. Various clinical trials of magnesium therapy for AMI have proffered conflicting results as to the efficacy of magnesium therapy because of significant differences in the timing of magnesium administration. Additional clinical trials that focus on early administration of magnesium are warranted to delineate the role of magnesium therapy for AMI. 相似文献
996.
The anterior approach for total hip endoprosthetics (THE) developed by K. J. Keggy was used in about 3,000 patients. It is characterized by rapid accomplishment, the possibility of anatomical inspection of the joint and correct orientation of the acetabular component of the endoprosthesis. Difficulties are not encountered in exposure of the femur and favorable conditions are provided for separation of the soft tissues. Considering our preference for noncemented THE, we have been using in the recent years a modified approach. The average duration of the operation, except for revision THE, did not exceed 90 minutes. The approach is atraumatic for the para-articular soft tissues, which provides the possibility of early postoperative mobilization and rehabilitation and reduced the duration of postoperative in-patient treatment to 7.3 days. The incidence of complications was not higher, and in many respects was even lower, than that reported in the literature dealing with primary and revision THE. At present we still use the anterior approach in all operations for THE although essential contradictions occur in discussion of the advantages of cemented implants over noncemented prostheses. The suggested method for THE is best for most patients. 相似文献
997.
H. H. Abou el Nage W. M. Abd el Azeim Fathy Zanib H. Ibrahim Saad 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1986,36(12):583-592
Styrene alkyl-methacrylate copolymers were synthesised at different monomer percentage ratios and under varied reaction conditions. Evaluation of obtained copolymers as viscosity index improvers in multigrade motor oils has been carried out in relation to different reaction variables and a comparative evaluation with commercially available viscosity index improvers in their performance properties (e.g. thermal oxidation and shear stabilities) was investigated. 相似文献
998.
BACKGROUND: The fourth American College of Chest Physicians Consensus Conference on Antithrombotic Therapy recently published guidelines that included recommendations regarding the management of excessive anticoagulation. Limited data are available to support these recommendations. OBJECTIVES: To assess management and outcomes of excessive anticoagulation in a group model health maintenance organization, compare management with the published guidelines, and analyze the cost of treatment strategies. METHODS: A search of computerized laboratory information identified patients with an international normalized ratio (INR) of greater than 6.0 during the 9-month study. Pertinent data were collected through a retrospective medical record review. Information was concurrently collected for cost analyses. RESULTS: The analysis included 301 episodes of excessive anticoagulation among 248 patients. Most (83%) episodes of elevated INRs were managed conservatively by a temporary discontinuation of warfarin sodium therapy until the INR was in a therapeutic range. Conservative management resulted in no sequelae in 212 (85.1%) of 249 episodes. Two episodes (0.8%) of major bleeding evolved in patients managed conservatively. No sequelae were documented in 23 (44%) of 52 episodes of phytonadione (vitamin K1) administration. Sixteen (31%) episodes of major bleeding were documented, but bleeding occurred before phytonadione administration in all cases. Administering phytonadione resulted in hospital admission for 3 patients--2 (3.8%) because of thromboembolism and 1 (1.9%) for the administration of heparin sodium. Cost-effectiveness analysis determined that treatment with phytonadione is 7 times more costly than conservative management when INRs are between 6.0 and 10.0. CONCLUSIONS: Most episodes of excessive anticoagulation were not managed per consensus guidelines. The higher the INR, the more likely were interventions to adhere to the guidelines. Administering phytonadione to patients with a moderate elevation of INRs (6.0-10.0) may be unnecessary. Based on this study, conservative management is a viable option. 相似文献
999.
In Wales, predictive testing for Huntington's disease (HD) has not been offered proactively to families and uptake of testing is low in comparison to other centres. Little is known of those not requesting testing, particularly those not in direct contact with the genetics service. This study examined differences between a cohort of 22 test applicants and a random group of 32 'non-requesters', drawn from the South Wales HD register. Respondents were interviewed by means of a semi-structured schedule in their own homes. The study groups differed significantly on a number of variables including: knowledge of the availability of testing; perceived attitudes of family members and significant others to testing; length of knowledge and perceived stressfulness of being at risk; and perceived ability to cope with an unfavourable result. Overall, knowledge of testing procedures was poor and at-risk individuals' understanding of genetic terminology was at odds with scientific distinctions. Discussion focuses on the organisational and psychological factors associated with lack of knowledge of the availability of testing and the interpretation of reported coping capacities. 相似文献
1000.
We previously reported that lithium stimulated extracellular glutamate accumulation in monkey and mouse cerebrocortical slices. We report here that this is caused by lithium-induced inhibition of glutamate uptake into the slice. Glutamate release was amplified 5-fold over inhibition of uptake. When the effects of lithium and the specific glutamate transporter inhibitors, L-trans-pyrrolidine-2, 4-dicarboxylic acid and dihydrokainic acid, were plotted as glutamate accumulation vs. inhibition of glutamate uptake, the plots were superimposable. This finding strongly indicates that lithium-induced glutamate accumulation is caused entirely by inhibition of uptake. With cerebrocortical synaptosomes, inhibition of glutamate uptake was greater than in slices, suggesting that presynaptic nerve endings are the primary site of inhibition of uptake by lithium. Inhibition of uptake was caused by a progressive lowering of Vmax, as the lithium concentration was increased, whereas the Km remained constant, indicating that lithium inhibited the capacity of the transporter but not its affinity. Chronic treatment of mice with lithium, achieving a blood level of 0.7 mM, which is on the low side of therapeutic, up-regulated synaptosomal uptake of glutamate. This would be expected to exert an antimanic effect. Lithium is a mood stabilizer, dampening both the manic and depressive phases of bipolar disorder. Interestingly, although the uptake of glutamate varied widely in individual control mice, uptake in lithium-treated mice was stabilized over a narrow range (variance in controls, 0.423; in lithium treated, 0.184). 相似文献