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131.
We describe three cases of CPPD crystal deposition disease in elderly patients whose main symptom was fever. Misdiagnosis of such cases is possible because of the similarity of the clinical picture to that of septic fever. The probable mechanisms causing the fever are discussed. There was spectacular improvement in these patients after a high dose of oral colchicine and loperamide and no relapse was observed during the long term administration of colchicine in a conservative dose together with supplementary magnesium.  相似文献   
132.
It is the position of the American College of Sports Medicine that adequate fluid replacement helps maintain hydration and, therefore, promotes the health, safety, and optimal physical performance of individuals participating in regular physical activity. This position statement is based on a comprehensive review and interpretation of scientific literature concerning the influence of fluid replacement on exercise performance and the risk of thermal injury associated with dehydration and hyperthermia. Based on available evidence, the American College of Sports Medicine makes the following general recommendations on the amount and composition of fluid that should be ingested in preparation for, during, and after exercise or athletic competition: 1) It is recommended that individuals consume a nutritionally balanced diet and drink adequate fluids during the 24-hr period before an event, especially during the period that includes the meal prior to exercise, to promote proper hydration before exercise or competition. 2) It is recommended that individuals drink about 500 ml (about 17 ounces) of fluid about 2 h before exercise to promote adequate hydration and allow time for excretion of excess ingested water. 3) During exercise, athletes should start drinking early and at regular intervals in an attempt to consume fluids at a rate sufficient to replace all the water lost through sweating (i.e., body weight loss), or consume the maximal amount that can be tolerated. 4) It is recommended that ingested fluids be cooler than ambient temperature [between 15 degrees and 22 degrees C (59 degrees and 72 degrees F])] and flavored to enhance palatability and promote fluid replacement. Fluids should be readily available and served in containers that allow adequate volumes to be ingested with ease and with minimal interruption of exercise. 5) Addition of proper amounts of carbohydrates and/or electrolytes to a fluid replacement solution is recommended for exercise events of duration greater than 1 h since it does not significantly impair water delivery to the body and may enhance performance. During exercise lasting less than 1 h, there is little evidence of physiological or physical performance differences between consuming a carbohydrate-electrolyte drink and plain water. 6) During intense exercise lasting longer than 1 h, it is recommended that carbohydrates be ingested at a rate of 30-60 g.h(-1) to maintain oxidation of carbohydrates and delay fatigue. This rate of carbohydrate intake can be achieved without compromising fluid delivery by drinking 600-1200 ml.h(-1) of solutions containing 4%-8% carbohydrates (g.100 ml(-1)). The carbohydrates can be sugars (glucose or sucrose) or starch (e.g., maltodextrin). 7) Inclusion of sodium (0.5-0.7 g.1(-1) of water) in the rehydration solution ingested during exercise lasting longer than 1 h is recommended since it may be advantageous in enhancing palatability, promoting fluid retention, and possibly preventing hyponatremia in certain individuals who drink excessive quantities of fluid. There is little physiological basis for the presence of sodium in n oral rehydration solution for enhancing intestinal water absorption as long as sodium is sufficiently available from the previous meal.  相似文献   
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Beclomethasone dipropionate nasal spray is widely used in the treatment of seasonal allergic rhinitis; however, the time of onset of action has not been determined. This study assessed the onset of action, level of relief, and efficacy of beclomethasone nasal spray in patients with seasonal allergic rhinitis. In a double-blind, randomized, placebo-controlled, parallel-group, multicenter, 7-day study, symptomatic patients were administered two inhalations of beclomethasone dipropionate (n = 80) or placebo (n = 81) into each nostril twice daily. Patients assessed the onset of action and level of relief at 6, 24, and 48 hours and at days 3 and 7. Investigators evaluated symptoms at days 0, 3, and 7 and response to therapy at days 3 and 7. The difference in the cumulative number of patients reporting relief of symptoms was statistically significant in favor of beclomethasone dipropionate by hour 24 (P = 0.05). Patients in the beclomethasone dipropionate group experienced a greater level of relief than patients receiving placebo at hour 24, and improvement increased over the 7-day study compared with a decrease in relief in the placebo group. Beclomethasone dipropionate was significantly more effective than placebo in reducing symptoms (P < or = 0.02), and patients in the beclomethasone dipropionate group showed a more favorable response to treatment than did patients in the placebo group (P < 0.01). Adverse events were minor in both groups. Beclomethasone dipropionate nasal spray produced significant onset of relief of symptoms the first day of treatment; improvement was sustained and increased over the course of the study.  相似文献   
134.
A fatal case of hantavirus pulmonary syndrome (HPS) in northern California prompted our attempt to isolate viruses from local rodents. From tissues of two deer mice, Peromyscus maniculatus, two hantaviruses (Convict Creek virus 107 and 74, CC107 and CC74) were established in cell culture. Viral antigens, proteins, and RNAs of the first and archetypical isolate (CC107) were examined, and portions of the medium (M) and small (S) genome segments of both isolates were sequenced. Antigenically, CC107 virus and the second isolate, CC74 virus, were more closely related to Puumala virus than Hantaan (HTN) virus, though distinct from both. Northern blots of viral RNAs showed the large and M segments of CC107 to be the same size as those of HTN virus, whereas the S segment was larger. Protein gels did not reveal CC107 to have a substantially larger nucleocapsid protein than HTN virus. Partial nucleotide sequence comparisons of CC107 and CC74 viruses revealed their M segments to be highly similar to one another, while their S segments differed by more than 10%. Nucleotide and deduced amino acid sequence comparisons showed the California isolates to be closely related to the newfound hantaviruses first detected in the Four Corners area and since incriminated in HPS through wide areas of the United States.  相似文献   
135.
Human immunodeficiency virus (HIV) infection has been associated with a wide spectrum of pulmonary disease. We report three HIV-seropositive patients with rapidly worsening airway obstruction associated with bronchiectasis. All subjects (age range 33-39 yrs) were cigarette smokers. Two had previously used intravenous drugs. The CD4 lymphocyte count ranged 40-250 cells x mm(-3). All individuals had complained of increasing dyspnoea for 3-6 months. Within 1 yr, they all developed severe airway obstruction with a decrease in both forced expiratory volume in one second (FEV1) and ratio of FEV1 to forced vital capacity (FEV1/FVC) to less than 60% of predicted value, and a decrease in mean forced expiratory flow at 25-75% of the forced vital capacity (FEF25-75) to less than 35% of predicted value. Computed tomography of the chest disclosed bilateral dilated and thickened bronchi. No classical causes of genetic or acquired bronchiectasis were identified in our patients. Recurrent bacterial bronchitis occurred in the follow-up period of the three patients. In conclusion, unusually rapid airway obstruction associated with bronchiectasis should be added to the wide spectrum of respiratory complications of human immunodeficiency virus infection.  相似文献   
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EPON--掀开光纤接入新的篇章   总被引:1,自引:0,他引:1  
邓羽  孙曙和  陈雪  刘冬 《电子质量》2003,(3):144-147
无源光网络的目的是通过建立一套成本低廉,且其带宽容量又是其他接入技术无法企及的端到端的解决方案,从而打破带宽的瓶颈。基于以太网的无源光网络EPON是一个点到多点的光接入网,采用低成本,高性能的以太网芯片为终端用户提供可靠的数据,话音以及视频业务,其所能提供的带宽远大于现有接入技术。本文主要介绍EPON技术的演化和分类、发展现状、网络结构、层次模型、关键技术和应用每几个方面。  相似文献   
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BACKGROUND: Registered mortality from cryptogenic fibrosing alveolitis (CFA) in England and Wales has increased substantially since the specific International Classification of Diseases code for CFA was introduced in 1979. However, since a significant proportion of deaths from CFA are misclassified as post inflammatory fibrosis (PIF), it is possible that the observed rise in CFA mortality is due to diagnostic transfer from this code. To investigate this, and to assess mortality trends in other countries, annual CFA and PIF mortality data from England and Wales, USA, Australia, Scotland, Canada, New Zealand, and Germany were analysed. METHODS: Crude annual mortality rates were calculated and rates standardised by Poisson regression to allow assessment of changes over time and comparison between countries, sexes, and age groups. The relative trends in mortality from CFA and PIF were assessed by calculating the annual ratio of CFA to PIF deaths. RESULTS: Men were more likely than women to die from both CFA and PIF in all countries. The highest standardised CFA mortality rate occurred in England and Wales, and the lowest in Germany. Since 1979 mortality from CFA has increased in England and Wales, Australia, Scotland and Canada, but there was no trend in CFA mortality in New Zealand or Germany. In the USA mortality from CFA was low and has fallen. Mortality from PIF increased in all countries except New Zealand and Germany, and the highest PIF mortality, together with the greatest increase over time, was seen in the USA. Changes over time in the annual ratio of CFA to PIF deaths in all countries were small, implying that diagnostic transfer is not a major cause of the increasing CFA mortality. CONCLUSIONS: Mortality from CFA continues to increase in England and Wales and in many other countries. Diagnostic transfer from PIF does not appear to be a major cause of this.  相似文献   
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