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1.
OBJECTIVE: To assess the effects of a non-elemental liquid diet on nutritional state, composition of bowel flora, intestinal translocation, and pulmonary infections after small bowel transplantation in pigs. DESIGN: Prospective randomised experiment. SETTING: Teaching hospital, Italy. MATERIAL: 32 female Large White pigs. INTERVENTIONS: Group 1 (n = 6) underwent small bowel transplantation, were treated with immunosuppression, and fed on commercial chow. Group 2 (n = 6) were treated similarly except that they were fed with an enteral feed through a tube gastrostomy starting on day 4 postoperatively. Group 3 (n = 6) were treated similarly to group 1 except that they had no immunosuppression, and Group 4 (n = 6) underwent orthotopic small bowel autotransplantation; 8 further pigs underwent a sham operation only to act as controls. MAIN OUTCOME MEASURES: Signs of rejection, graft-versus-host-disease, luminal bacterial overgrowth, bacterial translocation, pneumonia, and the pigs' nutritional state. RESULTS: All animals in group 3 showed signs of acute rejection. There was appreciable overgrowth of aerobic and anaerobic bacteria in all three groups after allotransplantation compared with controls. The counts of anaerobic bacteria were significantly lower in group 2 (enterally fed animals) compared with those given free access to commercial chow [mean (SD) 2.81 (1.39) log CFU/cm2 compared with 4.80 (1.65), p = 0.047]. Bacterial translocation developed to a similar degree after autografts and allografts and pneumonia developed in fewer animals after enteral feeding (1/6) than after conventional feeding (5/6) but the difference was not significant (p = 0.08, odds ratio 25.0, 95% confidence interval of odds ratio 1.20 to 521.13). Enterally fed animals also lost less weight than conventionally fed animals [2.32 (1.23) kg compared with 4.53 (1.74), p = 0.016]. CONCLUSIONS: Enteral feeding for up to a month slightly reduced the rate of pneumonia and resulted in a better nutritional state in pigs after small bowel transplantation. It had no effect on luminal bacterial overgrowth or translocation.  相似文献   
2.
Cooperative communications are effective in improving the performance and extend the coverage of wireless networks. One issue is to find proper methods to allocate cooperative nodes. In this paper we investigate the effects of relay position and power allocation strategy in cooperative communications employing space-time codes (STCs). We consider non-ideal links between source, relay, and destination enabling the analysis of relay allocation problem based on the performance of each link in realistic scenarios. The frame error rate for various channel conditions, available diversity, relay positions, and transmitted power levels is obtained. Both the situation of balanced and unbalanced transmit power levels for source, relay, and destination are compared. Cooperative pragmatic STCs in block fading channel (BFC) are considered for our analysis. The results provide insight on how to allocate relay nodes based on geometry, link quality, and transmitted power considerations.  相似文献   
3.
This paper introduces a prototype audio-biofeedback system for balance improvement through the sonification using trunk kinematic information. In tests of this system, normal healthy subjects performed several trials in which they stood quietly in three sensory conditions while wearing an accelerometric sensory unit and headphones. The audio-biofeedback system converted in real-time the two-dimensional horizontal trunk accelerations into a stereo sound by modulating its frequency, level, and left/right balance. Preliminary results showed that subjects improved balance using this audio-biofeedback system and that this improvement was greater the more that balance was challenged by absent or unreliable sensory cues. In addition, high correlations were found between the center of pressure displacement and trunk acceleration, suggesting accelerometers may be useful for quantifying standing balance.  相似文献   
4.

In this study, zinc–silica–borate glass structures doped with rare earth (RE) oxides Eu2O3 and Nd2O3 were synthesized with classical melting–quenching technique. 60ZnO–10SiO2–(30 – x)B2O3:xRE (x?=?0, 0.5, 1, 1.5 mol%) composition was chosen as the structure. The doping effect of two different rare earth oxides (individually) at different ratios was investigated according to the structural, physical, and optical properties of the glass structure. Structural properties of the synthesized glasses were determined with Fourier transform infrared (FTIR) device, and densities (ρ) and molar volumes (Vm) of the glasses were measured with Archimedes method, and optical properties were determined with UV–Visible (UV–Vis-NIR) device. FTIR results show that BO3 units increased in all RE-doped glasses. While densities of the synthesized glasses varied between 3.755 and 3.941 g cm??3, indirect bandgaps varied between 3.219 and 3.645 eV. The glass with the highest transmittance was the 1% Eu2O3-doped glass with a transmittance of 84%. While band edges shifted slightly toward short wavelengths in glasses doped with Nd2O3, they shifted to longer wavelengths in glasses doped with Eu2O3.

  相似文献   
5.
Ozone treatment of commercially available vegetable oils gives rise to the formation of chemical species that are responsible for the therapeutic properties of ozonated oil derivatives in dermatological diseases. In the last years, these products have been successfully used as a topical disinfectant in a number of serious skin affections. The medical application of empirically prepared ozonated oil has yielded striking improvements with unexpected and rapid healing, compelling us to begin a long-range study aiming first to define the main characteristics of the most common ozonated vegetable oils, about which there is usually no medical consensus because of the lack of standardization of their technological parameters. Sesame oil was selected because of its great amount of polyunsaturated acyl groups, as well as natural antioxidants. Moreover, we have determined the kinetics and optimal conditions of ozonation (e.g., ozone concentrations, time of exposure, temperature) for obtaining an ozonated oil characterized by well-established technological and physico-chemical properties, namely an accurate peroxide value determination. On the basis of the results, we have gained an understanding of the modifications of the vegetable oils during the ozonation process.  相似文献   
6.
 Thermal inactivation kinetics of crude peroxidase (POX) and lipoxygenase (LOX) in fresh pinto beans were studied over the temperature range of 55–90°C. The inactivation of both enzymes followed first-order kinetics. The biphasic inactivation curves for POX indicate the existence of several isoenzymes of varying heat stability. In the temperature range of 55–70°C, the activation energies (E a) of POX were 46.5 kcal·mol–1 for the heat-labile portion and 37.6 kcal·mol–1 for the heat-stable portion. On the other hand, the LOX enzyme had an E a value of 42.26 kcal·mol–1 at 55–75°C and 49.1 kcal·mol–1 at 55–90°C. Received: 28 July 1997 / Revised version: 16 October 1997  相似文献   
7.
Carbon nanotubes (CNTs) with hydrophobic and atomically smooth inner channels are promising for building ultrahigh‐flux nanofluidic platforms for energy harvesting, health monitoring, and water purification. Conventional wisdom is that nanoconfinement effects determine water transport in CNTs. Here, using full‐atomistic molecular dynamics simulations, it is shown that water transport behavior in CNTs strongly correlates with the electronic properties of single‐walled CNTs (metallic (met) vs semiconducting (s/c)), which is as dominant as the effect of nanoconfinement. Three pairs of CNTs (i.e., (8,8)met, 10.85 Å vs (9,7)s/c, 10.88 Å; (9,8)s/c, 11.53 Å vs (10,7)met, 11.59 Å; and (9,9)met, 12.20 Å vs (10,8)s/c, 12.23 Å) are used to investigate the roles of diameter and metallicity. Specifically, the (9,8)s/c can restrict the hydrogen‐bonding‐mediated structuring of water and give the highest reduction in carbon–water interaction energy, providing an extraordinarily high water flux, around 250 times that of the commercial reverse osmosis membranes and approximately fourfold higher than the flux of the state‐of‐the‐art boron nitrate nanotubes. Further, the high performance of (9,8)s/c is also reproducible when embedded in lipid bilayers as synthetic high‐water flux porins. Given the increasing availability of high‐purity CNTs, these findings provide valuable guides for realizing novel CNT‐enhanced nanofluidic systems.  相似文献   
8.
BACKGROUND: An association between celiac disease and primary biliary cirrhosis has been reported in a few cases, mainly as individual case reports. OBJECTIVES: To screen adult patients with celiac disease for primary biliary cirrhosis and patients with primary biliary cirrhosis for intestinal celiac involvement. METHODS: The celiac group consisted of 336 adults (218 women and 118 men; mean age, 36 yr; range 18-74 yr) with celiac disease diagnosed by serological and histological tests, 38 with newly diagnosed celiac disease and 298 with previously diagnosed celiac disease who were consuming a gluten-free diet. The mean follow-up period was 6 yr (range, 1-16 yr). Liver function parameters and autoantibody levels were determined, and, when indicated, histological tests were performed. The biliary cirrhosis group consisted of 65 subjects (58 women and seven men) (mean age, 59 yr; range, 35-67 yr) with primary biliary cirrhosis diagnosed 1-17 years previously (mean, 7 yr) on the basis of the usual biochemical, serological, and histological criteria. Antigliadin and antiendomysium antibody levels were determined, and two biopsy specimens from the distal duodenum obtained during endoscopy were evaluated. RESULTS: In patients with celiac disease, impairment of liver function was frequently found at diagnosis (16 of 38, or 44%), but primary biliary cirrhosis was diagnosed in only one case. In patients with primary biliary cirrhosis, no cases of celiac disease, as currently defined, were found. CONCLUSIONS: Our findings indicate that celiac disease and primary biliary cirrhosis are rarely associated and support the hypothesis that the intestinal lesions per se are not responsible for the liver disease.  相似文献   
9.
10.
We describe three men and two women, aged 18-50, with an occasional finding of increased aspartate and alanine aminotransferase and gamma-glutamyl transpeptidase levels in the absence of any drug treatment and past or current alcohol abuse. Two patients were overweight (body mass index 29 and 32, respectively) and physical examination was normal in all but one case. Tests for hepatitis A, B and C, Epstein-Barr virus, cytomegalovirus, toxoplasma and autoimmune hepatitis were negative and metabolic diseases (Wilson's disease, haemochromatosis, alpha-l-antitrypsin deficiency) were excluded by specific tests. Ultrasound liver scan revealed massive steatosis in all patients. Liver histology showed diffuse steatosis and parenchymal inflammation in all cases, with concomitant fibrosis and Mallory bodies in three of them. Findings were consistent with non-alcoholic steatohepatitis, a rare condition with potential progression to cirrhosis in a minority of cases. This disease, for which no treatment is currently available, must be considered in all subjects with elevated aminotransferases, in the absence of known causes of liver damage.  相似文献   
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