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1. The effect of electrophoretic ejection of philanthotoxin (the polyamine toxin, from the Egyptian digger wasp) was tested on responses of brainstem and spinal neurones in the pentobarbitone-anaesthetized rat to excitatory amino acids. 2. Philanthotoxin caused a dose-dependent reduction of responses to quisqualate, alpha-amino-3-hydroxy-5-phenyl-4-isoxazolepropionate (AMPA) and kainate with little effect on those to N-methyl-D-aspartate (NMDA). 3. The time-course of this antagonist action was slow. In particular the rate of recovery was dependent on frequency of ejection of the agonist. This agonist-dependent recovery suggests that philanthotoxin has a channel blocking mode of action on mammalian central neurones.  相似文献   
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Coexistence of spondyloarthritis (SpA) and Takayasu’s arteritis is not a common finding, but such cases have been discussed, particularly in the context of choice of therapy. Inhibition of inflammation by tumor necrosis factor inhibitors (TNFi) is a key aspect of the treatment of SpA and also positive effects of such treatment in concomitant large vessel vasculitis have been reported. However, TNFi is also associated with the possibility of initiating vasculitis.The present article based on a case study and the available literature is an attempt to discuss coexistence of these two diseases and the impact of treatment with biological drugs from the anti-TNF group in the course of SpA with Takayasu’s arteritis.  相似文献   
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BACKGROUND AND METHODS: The introduction of routine measles immunization in Israel in 1967 was followed by a 95% reduction in reported measles incidence. In 1990, a second measles immunization dose was instituted, and up until the end of 1999, 16 birth cohorts were offered the second dose. We present here changes in reported measles incidence in Israel following institution of the two-dose policy. RESULTS: First-dose coverage is 94%, and coverage for the second school-based dose exceeds 95%. A further 90% reduction in measles incidence has been observed and, following a modest national outbreak in 1994, measles incidence for 1995-99 stands at less than 3/100,000/year. CONCLUSIONS: Since measles is highly contagious, very high immunization coverage rates will be required to preserve these accomplishments, and measles elimination is still years away, but there is tentative evidence that measles containment is at hand. Even greater measles control can be anticipated as vaccine immunogenicity improves and successive cohorts of children come under the 2-dose regimen.  相似文献   
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Methane Dry Reforming is one of the means of producing syngas. CeNi0.9Zr0.1O3 catalyst and its modification with yttrium were investigated for CO2 reforming of methane. The experiment was performed at 800 °C to examine the effect of yttrium loading on catalyst activity, stability, and H2/CO ratio. The catalyst activity increased with an increase in yttrium loading with CeNi0.9Zr0.01Y0.09O3 catalyst demonstrating the best activity with CH4 conversion >85% and CO2 conversion >90% while the stability increased with increases in zirconium loading. The specific surface area of samples ranged from 1–9 m2/g with a pore size of 12–29 nm. The samples all showed type IV isotherms. The XRD peaks confirmed the formation of a monoclinic phase of zirconium and the well-crystallized structure of the perovskite catalyst. The Temperature Program Reduction analysis (TPR) showed a peak at low-temperature region for the yttrium doped catalyst while the un-modified perovskite catalyst (CeNi0.9Zr0.1O3) showed a slight shift to a moderate temperature region in the TPR profile. The Thermogravimetric analysis (TGA) curve showed a weight loss step in the range of 500–700 °C, with CeNi0.9Zr0.1O3 having the least carbon with a weight loss of 20%.  相似文献   
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Objective To compare the efficacy and safety of intravaginal misoprostol versus dinoprostone cervical gel for cervical ripening and labour induction. Methods We carried out an experimental clinical trial in which we enrolled 130 cervical consecutive patients with cervical ripening, randomly assigned to one of the following two treatment groups: (1) intravaginal misoprostol and (2) intracervical dinoprostone gel. A total of 50 μm of misoprostol was placed in the posterior vaginal fornix every 6 h for a maximum period of 24 h and 0.5 mg of dinoprostone was administrated in the uterine cervix every 6 h, for a maximum period of 24 h. The primary outcome measure was the number (rate) of women who went to vaginally deliver within 24 h of the protocol initiation. Results Among 130 patients evaluated, 65 were allocated to the misoprostol group and 65 to the dinoprostone group. The proportion of vaginal delivery within 24 h was significantly higher in the misoprostol group (75%) than in the dinoprostone group (53.8%) (RR = 1.40, 95% CI [1.07–1.45], P = 0.02). There was no significant difference between the mean time interval of delivery in the misoprostol group and the dinoprostone group (14.9 vs.15.8 h) (P = 0.51). The Bishop score was significantly higher in the misoprostol group, 6 h after the onset of the study (1.38; relative risk, 95% CI [1.02–1.85], P = 0.03). The Caesarean delivery rate for fetal distress was higher in the dinoprostone group (21 vs. 10.8%, P = 0.15). The tachysystole (Misoprostol 6.1% vs. dinoprostone 4.6%, relative risk 1.15, 95% CI [0.6–2.24]) and hyperstimulation syndrome rates (Misoprostol 7.6% vs. dinoprostone 4.6%, relative risk 1.26, 95% CI [0.72–2.24]) were slightly increased in the misoprostol group than in the dinoprostone group without reaching the level of statistical signification. Conclusion Misoprostol as used in this protocol is more effective than cervical dinoprostone gel application in the cervical ripening and labour induction. There is a tendency for an increase in the rate of tachysystole and hyperstimulation syndrome.  相似文献   
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BACKGROUND: This study documented the frequency and correlates of directly observed physicians' counseling on dietary habits and exercise in private medical practices. METHODS: Trained medical students observed physician, office, and patient characteristics in 4344 patient visits in 38 nonmetropolitan primary care physician offices. RESULTS: Counseling rates ranged from 0% in some offices to 55% in others. Physicians counseled patients on dietary habits in 25% of visits and exercise in 20% of visits. Physicians counseled new patients 30% more often than established ones (P < 0.05). Dietary counseling was associated with having dietary and exercise brochures in the office (P < 0.05). When counseling occurred, physicians (rather than patients) initiated both dietary and exercise counseling 61% of the time. Counseling for dietary habits was associated with counseling for exercise (P < 0.05); some physicians may be more likely to give preventive counseling. Counseling was not associated with physicians' age, years in practice, or number of patients per week. CONCLUSION: Physician counseled patients in 20-25% of visits, and this was not affected by physician characteristics. Results suggest that physician counseling protocols and other office prompts should be developed and promoted. Strategies targeting both physician and the health care system may improve the consistency of physician preventive counseling practices.  相似文献   
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Spark Plasma Sintering (SPS) has become a conventional and promising sintering method for powder consolidation. This study aims to well understand the mechanisms of densification encountered during SPS treatments, especially in the early stages of sintering. The direct current (DC) electrical behavior of copper granular medium is characterized. Their properties are correlated with their microstructural evolutions through post-mortem scanning electron microscope (SEM) observations to allow a thorough understanding of the involved Branly effect that is suspected to occur in SPS. The electrical response is studied by modifying the initial thickness of the oxide layer on particles surfaces and applying various mechanical loads on the granular medium. Without load and at low current, the measured quasi-reversible behavior is connected to the formation of spots at the microcontacts between the particles. By increasing the current, the Branly transition from an insulating to a conductive state suddenly occurs. The insulating oxide layer is destroyed, and micro-bridges are created. The application of a mechanical pressure strongly modifies the DC Branly effect. Increasing low stress leads to a strong decrease in the breakdown field. For high-applied pressure, successive drops in the electric field are detected during the electrical transition. These successive drops are induced by microcracking of the insulating oxide layer.  相似文献   
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