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991.
Enteral nutrition, as demonstrated by the many published papers, is not only safer and cheaper than parenteral supply of nutrients, but modulates an exaggerated cytokine response related to surgical trauma that leads to an increase in intestinal permeability, bacterial translocation and infection. The aim of enteral nutrition is to reduce the impact of cytokines on surgical patients and the related infectious complications. Via the enteral route the nutrients can reach the bowel lumen where enterocytes draw upon their fuel, preserving the barrier effect and modulating the cytokine response. Parenteral supply does not achieve this target since the blood supply of nutrients is not as important as the luminal supply. It is only via the enteral supply route that we can preserve the barrier effect. Since the cytokine response sets in immediately after a trauma such as surgery, we implement uninterrupted enteral nutrition, which means before, during and after surgery, plus parenteral support till the full calorie intake is achieved. In a hepatic resection study, we have demonstrated that enteral nutrition modulates the interleukin-6 immunological response and shortens both the period to bowel movement resumption and the duration of hospital stay. Aggressive enteral nutrition has also been implemented in severe pancreatitis, allowing control of the disease without the onset of septic complications. The most important target is not to achieve full calorie intake rapidly, but to supply the enteric mucosa continuously with useful immuno-nutrients, such as glutamine and fibres, to preserve the barrier effect, the mucus layer, and immunological status of the mucosa. In this way we have obtained significant results in the surgical treatment of these patients, reducing the infection rate and hospital stay. New prospects may be,possible in the fight against surgical infections by adding probiotics to enteral nutrition in order to improve the microenvironment of the colon.  相似文献   
992.
STUDY OBJECTIVE: To assess the clinical effectiveness of pulmonary rehabilitation (PR) after 10 or 20 consecutive sessions in outpatients with chronic airway obstruction (CAO). DESIGN: Observational prospective cohort trial. SETTING: Outpatient clinic of a rehabilitation center. PATIENTS AND INTERVENTIONS: Twenty-five outpatients (mean age, 65 +/- 9 years [+/- SD]; FEV1, 64 +/- 12% predicted) admitted to a comprehensive PR program, including exercise training. MEASUREMENTS AND RESULTS: The load reached on a cycloergometer (maximal achieved load [W-max]), the maximal and isoload dyspnea and leg fatigue on a Borg scale, 6-min walk distance (6MWD), and the health-related quality of life as assessed using the St. George's Respiratory Questionnaire (SGRQ) [total and components score] have been recorded as outcome measures at baseline, after 10 sessions (T10), and after 20 sessions (T20). The predefined criteria of the clinically significant improvement were as follows: + 15% W-max, + 54 m at 6MWD, - 1 point at isoload dyspnea and leg fatigue, and - 4% at SGRQ scores. There was a mean significant difference between changes at T20 and T10 for 6MWD (- 42.96 m; 95% confidence interval [CI], - 57.79 to - 28.12 m; p = 0.001), total SGRQ (4.80; 95% CI, 2.29 to 7.31; p = 0.001), activity SGRQ (3.60; 95% CI, 0.48 to 6.71; p = 0.025), and symptoms SGRQ (5.96; 95% CI, 2.72 to 9.2; p = 0.001). The percentage of patients who improved was different at T20 as compared with T10 for W-max (68% and 48%, respectively; p = 0.025), 6MWD (76% and 20%, p = 0.001), and total SGRQ (64% and 36%, p = 0.008). CONCLUSIONS: A 10-session course of PR provides only limited clinically significant changes of outcome measures when compared with a 20-session course in outpatients with CAO of mild-to-moderate severity.  相似文献   
993.
The increasing use of amiodarone as antiarrhythmic drug has raised the possibilities of dangerous effects from amiodarone-digitalis interaction. We have studied twelve patients who were taking digitalis and to whom amiodarone was administered because of arrhythmias. We found a 75,42% increase of digitalis plasma levels (p less than 0,001) in the early days of amiodarone therapy, and a 52,1% increase (p less than 0,001) in the medium term. An inverse correlation was found (r = -0,65; p less than 0,05) between the plasma levels of digitalis during the steady-state control period and during the following 2-to-6 months evaluation. Acute episodes of cardiac failure caused in our patients an abrupt increase of digitalis plasma levels: in three patients digitalis toxicity occurred. Based on our experience, we recommend that the dose of digitalis be halved when the two drugs are given together in patients with various degree of cardiac failure; moreover digitalis plasma levels should be frequently monitored in these patients. On the other hand digitalis administered according to age, sex, weight, kidney function, together with amiodarone, can be given at full dosage in patients without cardiac failure.  相似文献   
994.
BACKGROUND: An echocardiographic assessment of left ventricular (LV) diastolic dysfunction is still challenging when identifying a pseudonormal mitral pattern (PSE) in an unselected population. The present study analyzed and compared the accuracy of various parameters in correctly identifying a PSE pattern in patients with a broad range of ejection fraction (EF) and degree of mitral regurgitation. METHODS: Eighty-two patients with E/A > or = 1 and an invasive determination of left ventricular end-diastolic pressure (LVEDP) were enrolled in the study. Mitral E wave (E(max)) and A (A(max)) velocities, E (DTe) and A (DTa) deceleration times, pulmonary vein systolic and diastolic velocities, and time velocity integrals were measured. The different duration between mitral and pulmonary vein A wave (A'-A) also was calculated. E(max) and E/A during Valsalva maneuver were measured and expressed as percentage compared with baseline. LV end-diastolic (LVD), end-systolic (LVS), and EF were measured from the apical four-chambers view (area-length method). Left atrial end-systolic (LA(max)) and end-diastolic (LA(min)) were measured from the apical four- and two-chambers views (area-length method). Left atrial filling volume (LA(fill)) was the difference between LA(max) and LA(min). Mitral regurgitant volume was estimated by the following equation: MR(vol) = 6.18 + (1.01 * LA(fill)) - (0.783 * PVs %). RESULTS: Thirty-two patients (age: 55 +/- 21 years; 75% male) had LVEDP < or = 18 mmHg and were classified as normal mitral pattern (Group 1). Fifty patients (age: 57 +/- 22 years; 76% male) had LVEDP > 18 mmHg, and were classified accordingly as having PSE (Group 2). At logistic univariate analysis, DTa (0.005), LV EF (0.01), A'-A (< 0.0001) and % E/A (0.03) were the more powerful predictors of PSE. A'-A had the highest global accuracy in identifying PSE in patients with reduced (90%) and normal (88%) LV EF. CONCLUSION: A'-A has the highest accuracy in identifying PSE in an unselected population. This parameters should be implemented in routine echocardiography since it allows additional information about LV diastolic function assessment.  相似文献   
995.
Immunoglobulin binding on eosinophil surface receptors results in activation of these cells. Evaluating blood eosinophils from atopic subjects, it was investigated whether ligation of immunoglobulin E low-affinity receptor (FcepsilonRII/ CD23) with specific monoclonal antibodies (Mabs) resulted in enhanced eosinophil migration and adhesion molecule expression. Eosinophils from 20 subjects with allergic asthma (atopic individuals) and nine nonatopic normal individuals (controls) were purified using Percoll gradients. The effect of antihuman CD23 Mabs on: 1) eosinophil migration through human umbilical vein endothelial cells (HUVECs); and 2) eosinophil expression of the adhesion molecules leukocyte function-associated antigen-1 (LFA-1, CD11a/CD18), macrophage antigen-1 (Mac-1, CD11b/CD18) and very late activation antigen-1 (VLA-4, CD49d/CD29) was evaluated by specific Mab staining and flow cytometric analysis. As compared to controls, freshly isolated eosinophils from atopic individuals showed enhanced migration through HUVECs (p<0.05) and increased LFA-1 expression (p<0.01), but similar Mac-1 and VLA-4 expression (p>0.1 for both). In both controls and atopic individuals, eosinophil incubation with antihuman CD23 Mabs induced a dose-dependent increase in cell migration through HUVECs, significant at antihuman CD23 Mab concentrations of 5 microg x mL(-1) (p>0.05 for all). Similarly, incubation of the cells with antihuman CD23 Mabs induced dose-dependent upregulation of LFA-1 and Mac-1 expression, whereas no changes in VLA-4 expression were observed (p>0.1). Finally, the enhanced eosinophil migration induced by antihuman CD23 Mab stimulation was significantly inhibited by antihuman LFA-1 (84+/-14% (mean+/-SEM); p<0.01) and VLA-4 Mabs (47+/-15%; p<0.05) but not by antihuman Mac-1 Mabs (p>0.1). In both atopic and control subjects, immunoglobulin E, low-affinity receptor stimulation induces functional changes in eosinophils characterized by increased eosinophil migration associated with enhanced late function antigen-1 and Mac-1 expression.  相似文献   
996.
The optimal management of bleeding or its prophylaxis in patients with disorders of platelet count or function is controversial. The bleeding diathesis of these patients is usually mild to moderate: therefore, transfusion of platelet concentrates may be inappropriate, as potential adverse effects might outweigh its benefit. The availability of several anti-hemorrhagic drugs further compounds this problem, mainly because the efficacy/suitability of the various treatment options in different clinical manifestations is not well defined. In these guidelines, promoted by the Italian Society for Studies on Haemostasis and Thrombosis (Società Italiana per lo Studio dell'Emostasi e della Trombosi [SISET]), we aim at offering the best available evidence to help the physicians involved in the management of patients with disorders of platelet count or function. Literature review and appraisal of available evidence are discussed for different clinical settings and for different available treatments, including platelet concentrates (PC), recombinant activated factor VII, desmopressin, antifibrinolytics, aprotinin and local hemostatic agents.  相似文献   
997.
目的 通过构建健康信念模式和计划行为理论整合模型,探讨中年脑卒中患者自我管理行为意向的主要影响因素.方法 根据健康信念模式和计划行为理论自行设计问卷,对青岛市3所三级甲等医院的233例中年脑卒中患者进行调查,用结构方程分析健康信念模式与计划行为理论的各维度对自我管理行为意向的影响.结果 行为态度、主观规范、知觉行为控制对行为意向的总标准化路径系数分别为0.55、0.26和0.30,行为益处、行为障碍、严重感、危机感、主观规范对行为态度的总标准化路径系数分别为0.41、-0.14、0.63、-0.33和0.21,健康信念模式和计划行为理论中各变量对自我管理行为意向的决定系数(R2)为0.87.结论 行为态度是影响中年脑卒中患者自我管理行为意向的最重要因素,严重感是影响行为态度的最重要因素,行为益处、行为障碍、严重感和危机感通过影响行为态度间接影响行为意向,通过整合健康信念模式和计划行为理论2个理论增加了对行为意向的预测力度.建议今后可以尝试依据该整合模型为中年脑卒中患者制定个性化的行为干预措施.  相似文献   
998.
Background: Altitude‐induced sympathetic hyperactivity can elicit rhythm disturbances in healthy subjects, in particular during exercise. Aim: To asses the real susceptibility of healthy myocardium to malignant ventricular arrhythmias during exercise at high altitude using microvolt T‐wave alternans (MTWA). Methods: We evaluated eight healthy trained participants (one female, 42 ± 9 years) during a mountain climbing expedition on Gashembrum II (Pakistan, 8,150 m). MTWA and heart rate variability (HRV) were measured in each subject at sea level and at high altitude, both under rest conditions and during exercise. MTWA was determined with the modified moving average method. HRV was expressed as root mean square of successive differences. Results: Rest HRV at high altitude was significantly lower compared to rest HRV at sea level (36 ± 5 vs 56 ± 9 ms, P = 0.003). HRV during exercise was significantly lower with respect to rest condition both in normoxia (46 ± 7 vs 56 ± 9 ms, P = 0.0001) and hypoxia (27 ± 4 vs 36 ± 5 ms, P = 0.005). Moreover, HRV was significantly lower during exercise at high altitude compared to exercise at sea level (27 ± 4 vs 46 ± 7 ms, P = 0.0002) and arrhythmias were more frequent during exercise in hypoxia. Nevertheless, MTWA was absent under rest conditions both at sea level and at high altitude and minimally evoked during exercise in both conditions (22 ± 3 μV and 23 ± 3 μV, respectively, P = 0.2). Conclusions: In spite of an enhanced sympathetic activity, MTWA testing during exercise at high altitude was negative in all participants. Healthy trained subjects during exercise under hypoxia seem to be at low risk for dangerous arrhythmias.  相似文献   
999.
We studied the degradation of mixtures of o-cresol, m-cresol, and p-cresol, by Pseudomonas putida isolated from natural sources, and the application of this degradation to the depuration and detoxification of synthetic and industrial wastewater. Biodegradation assays were performed in batch and continuous-flow fixed-bed aerobic reactors. Biodegradation was evaluated by cresol determination using micellar electrokinetic capillary chromatography, UV spectrophotometry, and chemical oxygen demand (COD). Mineralization of cresols was assessed by gas chromatography performed both at the end of the batch process and in the continuous flow reactor effluent. Microbial growth was measured by the plate count method. Scanning electronic microscopy was employed to observe bacterial cells adsorbed on polyvinyl chloride cylinders in the reactor. Detoxification was evaluated by Vibrio fischeri, Pseudokirchneriella subcapitata, and Daphnia magna toxicity tests. Results obtained show that under batch conditions the strain grew exponentially with 100, 200, and 300 mg/L of each of the isomers in synthetic minimal medium within 48 h; in industrial wastewater with 540 mg/L of cresols similar results were obtained. Removal of cresols and COD was higher than 99.9% and 95.0%, respectively. When assays were performed in continuous flow reactor in synthetic wastewater under operating conditions a removal of total cresols and COD of 99.9% and 96.4%, respectively, was achieved. Results of capillary electrophoresis may suggest a concurrent isomers utilization and simultaneous growth on the substrates. Toxicity was neither detected at the end of the batch process nor in the continuous flow reactor effluent.  相似文献   
1000.
Calcitonin measurement in washout of the needle after aspiration (WO-Ct) has been rarely evaluated. Here we analyzed the role of WO-Ct in a series of subjects who underwent fine needle aspiration (FNA) with suspicious medullary thyroid cancer (MTC). Twenty-one patients referred following elevated serum calcitonin (S-Ct) or suspicious MTC by cytology. All patients underwent re-evaluation of S-Ct, FNA, and measurement of WO-Ct. S-Ct and WO-Ct were assessed by chemiluminescence assay (IMMULITE 2000, Diagnostic Products Corporation, USA). S-Ct showed elevated value in six subjects (mean 368.8 ± 373.9 pg/ml), of which three cases were cytologically classified as Class 5. WO-Ct obtained in this group (304.0 ± 309.3 pg/ml) was no different from S-Ct. After surgery MTC was confirmed in all patients. In the other 15 patients MTC was excluded by cytology or histology. Two subjects had moderately skewed S-Ct with nonmedullary histology. In the remaining 13 patients S-Ct resulted normal (6.2 ± 5.6 pg/ml) and WO-Ct low (2.9 ± 2.2 pg/ml). Significant (two-tailed P < 0.05, r(2) = 0.27, 95% confidence interval = 0.017-0.81) correlation was found between S-Ct and WO-Ct in nonmedullary patients but not in MTC patients. This study showed that WO-Ct can play a role in diagnosing primary and metastatic MTC. The procedure is easy, cost effective, and should be used in patients undergoing FNA with elevated S-Ct. Further studies and guidelines for the method are needed to use this technique in clinical routine. Until this any institute should use itself cut-off.  相似文献   
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