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81.
阿司匹林和塞莱昔布对幽门螺杆菌的体外影响   总被引:4,自引:0,他引:4  
目的:探讨阿斯匹林和选择性COX-2抑制剂塞莱昔布对体外培养的幽门螺杆菌(H pylori)生长、毒力因子及外膜蛋白的影响.方法:不同浓度的阿司匹林及塞莱昔布与H pylori共同培养,以活菌计数、分光光度计法检测H pylori的生长状态,分光光度计检测A 560nm值判断尿素酶活性,Hela细胞空泡变性实验和中性红吸收试验检测空泡毒素的活性,以SDS-PAGE电泳检测H pylori外膜蛋白的变化.结果:阿司匹林及塞莱昔布可以抑制H pylori的生长,此过程为剂量依赖性效应.阿司匹林0.5 mmol/L及塞莱昔布0.01 mmol/L时与DMSO对照相比H pylori24 h和48 h的菌落计数开始降低,随着两药剂量的加大菌落计数降低得更加明显,阿司匹林2.0 mmol/L和塞莱昔布0.04 mmol/L时H pylori被完全杀灭.阿司匹林及塞莱昔布可剂量依赖性的抑制H pylori的尿素酶活性及空泡毒素的活性.在对H pylori外膜蛋白的研究中发现,NSAIDs可能对H pylori的某种外膜蛋白表达有影响.结论:阿司匹林和塞莱昔布可抑制H pylori的生长、毒力因子的活性,并可能改变H pylori外膜蛋白的表达.  相似文献   
82.
Invasive breast cancer: mammographic measurement   总被引:3,自引:0,他引:3  
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83.
We surveyed and assessed 2,323 schoolchildren aged seven to 17 years from four schools in China, two in the city of Tianjin and the other two in a neighbouring rural village, Ban Chau, to investigate the prevalence of refractive error and its relationship with environmental factors. Every child from each of the participating classes was recruited in this study to avoid self-selection. A questionnaire was issued which queried some aspects of the child's visual habits and home. Refraction was canied out using the Canon R-22 autorefractor. The degree and frequency of myopia in these children increased almost linearly from age seven to 17 years. There was little difference between the urban and rural groups. Of the factors explored, the number of hours spent on near work showed the best correlation with the degree of myopia, albeit only weakly.  相似文献   
84.
The outcome of open pelvic fractures in the modern era   总被引:3,自引:0,他引:3  
BACKGROUND: Recent series have reported that the mortality rate of open pelvic fractures has decreased to < 10%. These injuries are often associated with intra-abdominal visceral damage, although few series have documented the prognostic significance of this injury complex. METHODS: A retrospective review in an urban level I trauma center of all patients who sustained open pelvic fracture between 1995 and 2004. RESULTS: Forty-four patients were identified as having sustained open pelvic fracture. Average Injury Severity Score was 30, with 77% of patients having a score > or = 16. Overall mortality was 45% (n = 20): 11 early deaths and 9 late deaths at an average of 17 days. Vertical shear injuries, although rare, were universally fatal. Other risk factors for overall mortality included revised trauma score, Injury Severity Score, transfusion requirement, Faringer zones I or II injury, Gustilo grade III soft tissue injury, need for therapeutic angiography, and presence of intra-abdominal injury, the latter of which conferred 89% mortality. Risk factors for late deaths also included pelvic sepsis, which occurred in 5 patients and was fatal in 3 (60%). CONCLUSIONS: The morbidity of open pelvic fractures remains high. Associated intra-abdominal injury or active arterial bleeding requiring therapeutic angiography is associated with a grim prognosis. There is a continuing need for new therapeutic approaches to this injury complex.  相似文献   
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87.
The nutritional management of patients with head injuries   总被引:2,自引:0,他引:2  
Severe head injuries tend to be associated with hypermetabolism and hypercatabolism resulting in negative nitrogen balances which may exceed 30 grams day-1. Enteral feeding should begin as soon as the patient is hemodynamically stable, attempting to reach a non-protein caloric intake of at least 30-35 kcal kg-1 day-1 and a protein intake of 2.0-2.5 g kg-1 day-1 as soon as possible. With severe head injuries (Glasgow Coma Scale < 8), there is an increased tendency for gastric feeding to regurgitate into the upper airway. Keeping the patient upright and checking residuals is important in such patients. Jejunal feedings are less apt to be aspirated. If it is apparent that the gastro-intestinal tract cannot be used to reach the nutritional goals within three days, total parental nutrition is begun within 24-48 h so as to reach these nutrition goals by either one or both routes by the third or fourth day. Blood glucose levels exceeding 150-200 mg dl-1 tend to increase the severity of the neurologic problems and efforts should be made to prevent hyperglycemia by carefully regulating the glucose and insulin intake. Indirect calorimetry to determine the respiratory quotient and resting energy expenditure should be determined twice weekly. To determine N2 balance, urinary urea nitrogen should be measured in 24-h specimens. These tests should be performed once or twice weekly until it is clear that the nutrition is adequate.  相似文献   
88.
BACKGROUND: The effects of blood alcohol on injury after crash are controversial, and safe limits are not settled. We examined if a positive blood alcohol concentration, even in a nontoxic range, affects management and outcome of injured patients after road crashes. METHODS: In this prospective cohort study, we recruited all adult subjects admitted to an emergency department within 4 hours after a road crash. Outcomes were mortality or expected permanent disability, and data related to patients' management. RESULTS: Alcohol-positive trauma patients were more frequently critical at admission (odds ratio [OR], 1.89; 95% confidence interval [CI], 1.18-3.02), and had an increased risk of combined mortality or expected permanent disability (OR, 1.67; 95% CI, 1.08-2.58), need for intensive care (OR, 1.87; 95% CI, 1.01-3.46), surgery (OR, 1.91; 95% CI, 1.37-2.66) and blood transfusions (OR, 2.09; 95% CI, 1.20-3.64), and acute medical complications (OR, 1.94; 95% CI, 1.33-2.85). All these events were explained by higher trauma severity. Only the risk of unsuspected injuries, diagnosed only at final evaluation, was independently associated with a positive blood alcohol concentration (OR, 4.98; 95% CI, 3.62-6.87), in addition to trauma severity and preexisting chronic conditions. Blood alcohol measurement significantly improved the accuracy in predicting unsuspected injuries, from 81.3% to 86.2%. CONCLUSION: In injured patients after a road crash, a positive blood alcohol concentration increases the chance that the final diagnosis will include more injuries than initially documented. More careful monitoring is needed in alcohol-positive trauma patients, independent of clinical status, injury severity, and overt symptoms of alcohol intoxication.  相似文献   
89.
Most in vitro studies of capillary permeability focus on endothelial cell (MVEC) monolayers and ignore the second cell that forms the capillary wall: the microvascular pericyte (PC). We describe a model to study the permeability characteristics of MVEC, PC, and MVEC:PC cocultures. METHODS: Semipermeable culture inserts were coated with collagen and then plated with early passage bovine pulmonary MVEC. On Day 3, bovine pulmonary PC were added at concentrations to approximate MVEC:PC ratios of 1:1, 5:1, and 10:1. Electrical resistance was measured on subsequent days and fluorescently labeled (FITC) albumin was used in a permeability assay to calculate an albumin clearance for each culture. RESULTS: The results for electrical resistance measurements and albumin assays showed a similar pattern. Resistance for endothelial cell monolayers was significantly higher and albumin permeability was significantly lower than that of controls. Addition of pericytes at a 10:1 and 5:1 ratios increased the permeability barrier compared to endothelial cells alone, although these cultures were not significantly different from one another. Cocultures at a 1:1 ratio had the best barrier, significantly better than all other cultures. CONCLUSIONS: Endothelial cell monolayers are an inadequate model of the microcirculation. As PC form a key component of the capillary wall in vivo and as addition of PC to MVEC monolayers in vitro, optimally at a 1:1 ratio, increase their barrier effect to large and small molecules, we believe it is necessary to include both cells in future in vitro studies.  相似文献   
90.
The aim of the study was to assess, on a large group of spontaneous or induced sputum samples, the difference in quality between slides processed by two different methods, and the relationship between quality assessment and some clinical and functional characteristics of the examined subjects. We examined 631 sputum samples obtained from 337 subjects with proven (n = 291) or suspected bronchial asthma. Of these, 467 samples were processed using the whole-sample method (Group I), while 164 samples were processed using the plug method (Group II). Salivary contamination, cell distribution on the slide, and cell borders were evaluated, and samples were classified as inadequate, adequate, or good. Inadequate samples were equally represented in both groups, while good samples were represented more in Group II. No significant difference in most clinical and functional findings was observed between the different quality categories of both groups. A higher proportion of inadequate samples was observed in Group I samples spontaneously collected. Mild intermittent asthmatics produced a better quality of slides in comparison with other groups of asthma severity. In conclusion, sputum quality partially depends on the different methods of sputum collection and/or processing, although the percentage of inadequate samples is similar for the two methods of processing. Sputum quality is only marginally affected by clinical and functional characteristics of asthma, or by asthma severity.  相似文献   
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