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81.
BACKGROUND: Lung infection with Burkholderia cepacia complex before lung transplantation in patients with cystic fibrosis is a major risk factor for decreased post-operative survival rates compared with those of patients colonized with the more common opportunistic pathogen Pseudomonas aeruginosa. Because adherence to mucosal surfaces is an important initial step in infection, we investigated the use of non-toxic neutral polysaccharides and a sugar alcohol to prevent adherence of B cepacia complex to allograft airway epithelium. METHODS: We used human airway explants prepared from donor tracheobronchial tissue to test the effect of dextrans and xylitol in inhibiting the binding of Burkholderia cepacia complex. We used immunofluorescence and electron microscopy to determine the distribution of bacteria in the explants. RESULTS: Burkholderia cepacia complex bound to the explants and was found only in the surface mucus layer. Dextran 40 kd applied before adding the bacteria decreased the number of bound organisms by 80% to 99%. Smaller molecular mass dextrans (4 and 20 kd) were ineffective. Xylitol inhibited bacterial binding by 67% to 85%. Both agents seemed to decrease the thickness of the surface mucus, suggesting that they may indirectly inhibit bacterial binding by removing adherent surface mucus. CONCLUSIONS: Treating donor lungs with dextran 40 kd or xylitol before (and possibly after) surgery may inhibit the adherence of Burkholderia cepacia complex to airways and may prevent or decrease subsequent infection of the allografts.  相似文献   
82.
CONTEXT AND OBJECTIVE: Many children with acute lower respiratory tract infections (ALRI) present to the emergency ward with concurrent wheezing. A chest x-ray is often requested to rule out pneumonia. We assessed inter-observer agreement in interpreting x-rays on such children. DESIGNS AND SETTING: Prospective consecutive case study at Instituto de Salud del Ni?o, Lima, Peru. METHODS: Chest x-rays were obtained from eligible children younger than two years old with ALRI and concurrent wheezing who were seen in the emergency ward of a nationwide pediatric referral hospital. The x-rays were read independently by three different pediatric residents who were aware only that the children had a respiratory infection. All the children had received inhaled beta-adrenergic agonists before undergoing chest x-rays. Lobar and complicated pneumonia cases were excluded from the study. RESULTS: Two hundred x-rays were read. The overall kappa index was 0.2. The highest individual kappa values for specific x-ray findings ranged from 0.26 to 0.34 for rib horizontalization and from 0.14 to 0.31 for alveolar infiltrate. Inter-observer variation was intermediate for alveolar infiltrate (kappa 0.14 to 0.21) and for air bronchogram (kappa 0.13 to 0.23). Reinforcement of the bronchovascular network (kappa 0.10 to 0.16) and air trapping (kappa 0.05 to 0.20) had the lowest agreement. CONCLUSIONS: There was poor inter-observer agreement for chest x-ray interpretation on children with ALRI and concurrent wheezing seen at the emergency ward. This may preclude reliable diagnosing of pneumonia in settings where residents make management decisions regarding sick children. The effects of training on inter-observer variation need further studies.  相似文献   
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BACKGROUND: High rates of morbidity and mortality are observed in patients with advanced heart failure (AHF). AHF is now considered the most costly syndrome in cardiology owing to the substantial economic burden associated with hospitalizations for acute decompensation. A management program that involves specialized follow-up by a multidisciplinary team has been suggested as a desirable strategy for improving outcomes for these patients. ObjectivE: To evaluate the impact of a specialized outpatient heart failure (HF) follow-up program for patients with AHF on frequency and duration of hospitalization for HF and functional status. METHODS: We retrospectively studied 167 consecutive patients with AHF who were referred to the outpatient HF follow-up program in our institution between January and November 2002, of whom 147 followed for > or =30 days were included in the analysis. In addition to demographic and baseline clinical characteristics, HF medication and NYHA functional class, the number and duration of hospitalizations for HF during the previous 12 months were recorded and compared at the time of referral and after a follow-up period of 6.5+/-3 months. RESULTS: Of the 147 patients analyzed (aged 60.8+/-13 years; 79% male; left ventricular ejection fraction 27+/-11%), 67% were in NYHA functional class III, 20% in class II and 13% in class IV at the time of referral. There was a significant improvement in functional class during the mean follow-up period: 55% of the patients were in class III, 37% in class II, 5% in class I and 3% in class IV (p<0.0001). The proportion of patients on beta-blockers or spironolactone increased from 33% and 51% at the time of referral to 69% and 71% respectively after referral (p<0.0001). In the 12 months before referral, 39% of the patients had been hospitalized for acute decompensation of HF (87 hospitalizations - mean 7.2/month) versus 13% of the patients during the mean follow-up period (25 hospitalizations - 3.8/month, p<0.0001). No significant differences were found in the proportion of patients on angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers, digoxin or diuretics, or in the mean duration of hospitalization before and after referral. ConclusioN: The specialized follow-up of patients with AHF by a team with expertise in HF resulted in significant therapeutic optimization. Increased use of beta-blockers and spironolactone was associated with significant improvement in functional capacity and significant reduction in hospitalizations.  相似文献   
86.
After total gastrectomy, the ileocecal graft may act as a reservoir and protect against reflux but give rise to transposition of the ileum and cause possible changes in bile acid metabolism and nutrition. This study compared the ileocecal graft and jejunal pouch. Male Wistar rats weighing 265 +/- 22 g were submitted to sham operation (S), ileocecal interposition graft (IIG), and jejunal pouch interposition graft (JP) after total gastrectomy. Eight weeks later, the esophagus was examined for evidence of esophagitis. Nutritional biochemistry and weight profile were documented preoperatively and 8 weeks after surgery. The oral glucose tolerance test was performed. Thirty-three rats were operated on and 30 survived for 8 weeks. Esophagitis occurred in seven JP rats. Body weight was significantly higher in IIG than in JP rats (p < .05). Normal glucose tolerance to intragastric glucose load was observed in sham and operated rats. JP rats had a significant decrease in serum albumin, glucose, transferrin, hemoglobin, iron, folate, and calcium, compared to sham (p < .05). Cobalamine was significantly lower in IIG rats than in JP rats (p < .05). In the IIG and JP groups, serum/hepatic total bile acid did not differ significantly from preoperative and sham values. In conclusion, the IIG interposition graft in rats prevented esophagitis, preserved nutrition, and did not interfere with enterohepatic total bile acid circulation.  相似文献   
87.
PURPOSE: To determine if deliberate hypotension decreases blood loss and transfusion requirements in patients undergoing orthopedic surgery, a systematic review of all randomized trials addressing this issue was undertaken. METHODS: Electronic databases, citations lists and review articles were searched for potential articles. Relevant articles met the following inclusion criteria: English language, humans undergoing orthopedic surgery, deliberate hypotension used by any method, intraoperative blood loss measured as an outcome, and the trial methodology being randomized and controlled. Four outcomes were analyzed, including estimated blood loss, blood transfused, surgery duration, and quality of the surgical field. For all analyses, the random-effects model was used. RESULTS: Seventeen articles met the inclusion criteria. The surgeries studied included total hip arthroplasty (seven), orthognathic surgery (eight), total knee arthroplasty (one) and spinal fusion (one). A total of 636 patients were randomized across all studies. For blood loss, the overall weighted mean difference favoured treatment, with a savings of about 287 mL of blood [95% confidence interval (CI): -447, -127]. The mean differences also showed a statistically significant benefit for deliberate hypotension in reducing transfusion requirements (-667 mL of blood transfused; 95% CI: -963, -370). Deliberate hypotension was not shown to reduce the duration of surgery (-1.9 min of surgery; 95% CI: -7.2, 3.5) or improve surgical conditions (surgical field quality rating -0.5; 95% CI: -1.1, 0.2). CONCLUSION: This review provides some support for the use of deliberate hypotension in reducing blood loss and transfusion requirements in orthopedic surgery, but these results are tempered by the small sample sizes and poor methodological quality of published studies.  相似文献   
88.
To examine the relationship between demographic, clinical and psychosocial variables and diabetes self-care management in Mexican type 2 diabetic patients. Cross-sectional study of 176 consecutive patients with type 2 diabetes aged 30-75 years, attending a tertiary health-care center in Mexico City. A brief medical history and previously validated questionnaires were completed. The study group consisted of 64 males/112 females, aged 55 +/- 11 years, mean diabetes duration of 12 +/- 8 years and HbA1c of 9.0 +/- 2.0%, 78.4% reported following the correct dose of diabetes pills or insulin, 58% ate the recommended food portions, and 44.3% did exercise three or more times per week. A good adherence to these three recommendations was observed in only 26.1% of the patients. These patients considered as a group were characterized by a greater knowledge about the disease (P < 0.00001), regular home blood glucose monitoring (P < 0.01), an inner perception of better diabetes control (P = 0.007), good health (P = 0.004) and better communication with their physician (P < 0.02). A poor adherence to two or the three main diabetes care recommendations was associated with a depressive state (OR 2.38, 95% CI 1.1-4.9, P < 0.01) and a history of excessive alcohol intake (OR 4.03, 95% CI 1.1-21.0, P = 0.03). Poor adherence to standard diabetes care recommendations is frequently observed in patients with type 2 diabetes attending a specialized health care center in Mexico City. Depression must be identified and treated effectively.  相似文献   
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The purpose of this research was to verify the influence of Iodoform on antimicrobial potential of calcium hydroxide. S. aureus, E. faecalis, P. aeruginosa, B. subtilis, C. albicans were the biological indicators. The substances tested were: calcium hydroxide + saline; calcium hydroxide + Iodoform + saline; Iodoform + saline. For the agar diffusion test, 18 Petri plates with 20 ml of BHI agar were inoculated with the microbial suspensions. Fifty-four cavities were made and filled with the substances tested. The diameters of microbial inhibition were then measured. In direct exposure test, 162 #50 sterile absorbent paper points were immersed in the experimental suspensions for 5 min, and covered with the pastes. At intervals of 24, 48 and 72 hours, the paper points were immersed in 10 ml of Letheen Broth, followed by incubation at 37°°C for 48h. Microbial growth was evaluated by turbidity of the culture medium. A 0.1 ml inoculum obtained from the Letheen Broth was transferred to 7 ml of BHI, and incubated at 37°°C for 48h. Bacterial growth was again evaluated by turbidity of the culture medium. The calcium hydroxide associated with the saline or the iodoform plus saline showed antimicrobial effectiveness in both experimental methods. The iodoform paste presented antimicrobial ineffectiveness for the agar diffusion test on all biological microorganisms and for the direct exposure test on B. subtilis and on the mixture.  相似文献   
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