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71.
RATIONALE: The effects of caffeine on psychomotor performance have been evaluated under resting conditions and in a thermoneutral environment. Our hypothesis was that these effects could be modified by factors enhancing the level of alertness, such as exercise and cold exposure. OBJECTIVE: The purpose of this study was to follow up changes in the multiple choice reaction time (RT) during exercise at room and low ambient temperatures after caffeine or placebo administered in a double blind manner. METHODS: Nine soccer players performed multistage, incremental exercise until volitional exhaustion on a bicycle ergometer at 22 degrees C or 4 degrees C, 1 h after ingestion of coffee with caffeine (CAF) or without it (PL). Immediately before exercise and at the end of each workload, RT and blood lactate (LA) were measured. Oxygen uptake (VO2) and heart rate (HR) were recorded continuously. Blood LA threshold and the workload associated with the shortest RT were determined. RESULTS: During exercise at 22 degrees C, RT was significantly shorter in CAF than in the PL test, while at 4 degrees C there were no differences in RT between CAF and PL trials. Cold exposure did not affect RT either at rest or during exercise. Neither caffeine nor cold exposure influenced the maximal VO2, the maximal HR and LA threshold. CONCLUSION: In the thermoneutral environment, caffeine ingestion improved psychomotor performance during exercise, whilst at low ambient temperature this effect was blunted. These findings suggest that the stimulating action of caffeine depends on the level and source of arousal.  相似文献   
72.
The effect of barium on blood in the gastrointestinal tract   总被引:2,自引:0,他引:2  
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73.
Background: The purpose of the present paper was to describe the clinical manifestations and treatment of patients with panniculitis. Methods: From January 1983 to December 2002, 4294 patients were treated for pediatric rheumatological diseases at Pediatric Rheumatology Unit, University of São Paulo, Brazil. Of these, 35 children and adolescents (0.8%) presented with panniculitis: erythema nodosum (EN) or Weber–Christian disease (WCD). Clinical characteristics, laboratory exams, biopsy of the lesion, treatment and clinical course were studied. Results: Of the 35 patients, 29 presented with EN and six with WCD, one of these with cytophagic histiocytic panniculitis. Mean age at symptom onset was 85 months (6–204 months) and the mean duration of follow up was 55 months (1–144 months). All the patients presented with inflammatory subcutaneous nodules. The patients with WCD presented with systemic manifestations and cutaneous atrophy. The principal etiologies of EN were streptococcal infection (42%), undetermined (13.5%), pulmonary tuberculosis (10%), and acute rheumatic fever (10%). Biopsy of the nodules indicated septal panniculitis in 14 patients with EN and lobular panniculitis without vasculitis in the patients with WCD, one of which had cytophagic histiocytic panniculitis. There was recurrence in 11 patients (38%) with EN and in all those with WCD. Non‐steroidal anti‐inflammatory drugs were used in 15 patients with EN and corticosteroids and/or immunosuppressive drugs in the six patients with WCD. Three patients died. Conclusions: EN is the most frequent panniculitis, with a benign course and is mainly associated with infections. WCD is a severe disease, with systemic involvement, that proceeds with cutaneous atrophy and requires the use of corticosteroids and or immunosuppressive drugs.  相似文献   
74.
A major complication of cholestasis is fat malabsorption related to decreased intestinal bile acids, which leads to malnutrition and fat-soluble vitamin deficiency. The impaired excretion of bile acids leads to a low intraluminal micellar concentration that causes long-chain triglyceride lipolysis and absorption to be ineffective. Medium-chain triglycerides (MCTs) are more readily absorbed when there are low concentrations of bile acids and therefore are a good source of fat calories; MCTs can be administered as MCT-containing formulas. In those children who are unable to take sufficient calories by mouth, it is important to start nocturnal enteral feeding to improve nutritional status. In infants with cholestasis, the absorption of fat-soluble vitamins (A, D, E and K) that require bile acids is also impaired, and supplementation is mandatory. Vitamin K deficiency may be responsible for hypoprothrombinaemia, which may lead to bleeding diathesis, Vitamin K (phytomenadione) should therefore be promptly administered intravenously, at a dose of 1 mg. Chronic vitamin E (α-tocopherol) deficiency is associated with a progressive neuromuscular syndrome that can cause cerebellar ataxia, areflexia and peripheral neuropathy. Supplements are given orally in doses of 3–5 times the normal requirement if cholestasis is incomplete. In complete cholestasis, supplements must be given intramuscularly at monthly intervals. In infants who fail to thrive, dietary supplements of carbohydrate polymers and MCTs are required.  相似文献   
75.
目的 探讨勃脉力A注射液对体外循环心脏手术患者肝功能的影响.方法 选择术前肝功能正常、无肝炎病史的行体外循环心脏手术患者60名,随机分为勃脉力A组(P组)和林格液组(R组).所有患者均在术前、术后2h、1d、3d、7d分别采肘正中静脉血和挠动脉血:静脉血分离血清后应用自动血生化分析仪检测血清中天冬氨酸转氨酶和丙氨酸氨基转移酶,以了解患者的肝脏功能改变;抽取动脉血查乳酸浓度.术中及术后密切观察患者血压、心率、中心静脉压、尿量等,观察并记录患者拔管及停留ICU时间.结果 与R组相比较,在术后各时间点P组ALT、AST及乳酸浓度均显著降低(P﹤0.05),并且拔除气管导管时间和停留ICU时间均有所缩短.结论 勃脉力A注射液能够显著降低体外循环术中乳酸浓度,并能改善患者肝功能,非常适用于体外循环手术.  相似文献   
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78.
Quantification of protein binding of new chemical entities is an important early screening step during drug discovery and is of fundamental interest for the estimation of safety margins during drug development. In this publication, we describe the development of a new high-throughput assay for the determination of the free drug fraction in plasma (fu). The new technique is an enhancement of the previously published erythrocytes partition method. It is based on the distribution of drugs between plasma water, plasma proteins, and solid-supported lipid membranes (Transil). The execution of protein binding studies by partitioning is dramatically simplified by substituting erythrocytes with commercially available Transil beads, and makes the method particularly suitable for high-throughput studies. Eight Bayer compounds from different compound classes covering a wide range of lipophilicities (log P = 1.9-5.6) and fu values (0.018-35%) were selected for validation of the assay. The results obtained by the new method and by either the erythrocytes partitioning technique or more conventional methods (ultrafiltration and equilibrium dialysis) are identical, confirming that the new method produces valid results even for drugs that are strongly bound to plasma proteins. Precision and accuracy of the data in the cases of very low and high fu values are comparable, indicating that the method is especially suited for highly lipophilic drugs that tend to adsorb to surfaces compared with other methods, like ultrafiltration or equilibrium dialysis, that may produce biased data. The method is also useful for the determination of binding parameters and the pH dependence of fu. In summary, this assay is well suited for high-throughput determination of protein binding during drug discovery and for extended protein binding studies during drug development.  相似文献   
79.
目的:探讨外旋外展推顶法治疗肩关节前脱住可行性及疗效。方法:自1995年1月~2009年12月,采用外旋外展推顶法治疗肩关节前脱住500例,治疗后根据恢复症状及并发症,分析治疗方法的可行性及疗效。结果:所有患者均获得随访,时间为6个~1年;500例治愈432例。好转68例,无效O例。结论:外旋外展推项法治疗肩关节前脱住是一种可行的方法,较其他方法有更大的优点。  相似文献   
80.
Objectives To assess the prevalence of high blood pressure amongst postpartum women in rural Tanzania, and to explore factors associated with hypertension prevalence, awareness, treatment, and control. Methods 1849 women in Tanzania’s Pwani Region who delivered a child in the prior year participated in the study. We measured blood pressure, administered a structured questionnaire and assessed factors associated with the prevalence, awareness, treatment, and control of hypertension (HTN) using bivariable and multivariable logistic regressions. Findings 26.7% of women had high blood pressure and/or were taking antihypertensive medication. Women were on average 27.5 years old (range 15–54). Nearly all women (99.5%) reported contact with the health system during their pregnancy and delivery, with an average of 5.2 visits for their own care in the past year. Only 23.5% of those with HTN were aware of their diagnosis, 17.4% were taking medication, and only 10.5% had controlled blood pressure. In multivariable analysis, facility delivery, health insurance, and increased distance from a hospital were associated with increased likelihood of HTN awareness; facility delivery and hospital distance were associated with current hypertensive treatment; younger age and increased hospital distance were associated with control of HTN. Conclusion The prevalence of high blood pressure in this postpartum population was high, and despite frequent recent contacts with the health system, awareness, treatment and control of HTN were low. These findings highlight an important missed opportunity to improve women’s health during antenatal and postnatal care.  相似文献   
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