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1.
BACKGROUND: To determine the best cutoff values of aspartate aminotransferase (AST) and alanine amino-transferase (ALT) in detecting viral hepatitis C infection among patients of continuous ambulatory peritoneal dialysis (CAPD). METHODS: 90 (44 male and 46 female) CAPD patients and 526 adult controls (266 male, 260 female) were enrolled. Serum AST and ALT were measured by an auto-analyser monthly. Serum HBsAg was examined using a RIA method and anti-HCV by an second-generation EIA method. The best cutoff values of AST and ALT for detecting viral hepatitis were obtained from the ROC (receiver-operating characteristic) curve. RESULTS: The prevalence of anti-HCV(+) was significantly higher in CAPD patients (16.7%) than in normal controls (4.9%), while that of HBsAg(+) was similar in both groups. CAPD patients had significantly lower levels of serum aminotransferases compared to normal controls. Mean AST were 23.8 IU/l in normal control and 18.8 IU/l in the CAPD patients (P < 0.001). Mean ALT were 21.9 IU/l in normal controls and 15.3 IU/l in the CAPD patients (P < 0.001). CAPD patients with HCV infection had higher serum AST and ALT levels than those without. However, HBV infection did not cause significant serum aminotransferase elevation in patients. The conventional cutoff values of AST (40 IU/l) and ALT (40 IU/l) for detecting viral hepatitis yielded only a sensitivity of 27.3 and 18.2% respectively; on the contrary, our revised cutoff values of AST (24 IU/l) and ALT (17 IU/l) had better sensitivities (AST, 72.7%; ALT, 63.6%). For serial aminotransferase values, the sensitivity of AST and ALT for detecting HCV were 36.4 and 27.3% by conventional criteria, and were both 81.8%, by our newly revised criteria. CONCLUSIONS: Serum aminotransferase cutoff values should be modified for screening viral hepatitis in a CAPD population. Our new cutoff criteria had important clinical implications in providing benefits of earlier detection and possible prevention from chronic hepatic deteriorations. 相似文献
2.
KC Murray 《Canadian Metallurgical Quarterly》1994,87(3):186-187
Primary psoas abscess is a relatively rare disease with highest incidence in children and adolescents. It usually presents with fever, abdominal pain and limp. Limping tends to incriminate musculoskeletal problems below the pelvis, but movement of the hip involves the psoas muscle which is mostly retroperitoneal and intimately related to pelvic and intraperitoneal organs. Although the current tendency is to use abdominal sonography, rectal examination is still a valuable step in clinical examination, and may help to assess a pelvic mass or abscess. The following case report describes the elusive nature of psoas abscess and a rare occurrence of abscess rupture and peritonitis, immediately after rectal examination. 相似文献
3.
J.A. Bakken L. Barone D. Braun M. Caillat C. Dionisi C. Dor H. Elmamouni F. Ferroni G.L. Grazer J.T. He R. Herbiet B. Ille P. Lecomte E. Longo P.F. Loverre Y.S. Lu J.P. Martin U. Micke R.P. Mount P.A. Pirou H.-G. Sander D. Schmitz M. Schneegans D.P. Stickland R.L. Sumner K.L. Tung E. Valente M. Vivargent 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1985,228(2-3):294-302
A calorimeter of 25 bismuth germanate (BGO) crystals equipped with silicon photodiode readout has been tested at the CERN SPS in the energy range 1–50 GeV. The response for electrons has been shown to be linear in this energy range and the rms resolution obtained (
) is approximately 1%, for E > 4 GeV. The electron/pion separation was found to be better than 1:500 in the energy range 1–20 GeV. Data on lateral and longitudinal shower development were compared with the results of a Monte Carlo simulation using the SLAC-EGS program and found to be in good agreement. 相似文献
4.
We examined the molecular mechanism of metronidazole resistance by constructing a lambda-Zap II phagemid expression library with genomic DNA from a metronidazole-resistance strain of Helicobacter pylori. Twenty-two clones were found to have elevated MTZ resistances in XLOLR strain of E. coli. Phagemids belonging to the twenty two clones were extracted and then retransformed into the XLOLR strain of E. coli. After MTZ selection, five clones could confer metronidazole resistance consistently. According to Southern hybridization and DNA sequencing, the five clones contained a same locus, recA. In addition, transforming the five clones into BL21 strain of E. coli produced a higher resistance to MTZ. Interestingly, electroporation of one of the five phagemid clones into two MTZ sensitive H. pylori yielded MTZ resistant strains. Comparing amino acid sequence in MTZ resistant with sensitive isolates revealed two point mutations at this locus. Above results suggest that mutation in recA may be associated with metronidazole resistance of H. pylori. 相似文献
5.
The AlCoCrCuFeNi high-entropy alloy system was synthesized using a well-developed arc melting and casting method. Their elemental effect on microstructures and hardness was investigated with X-ray diffraction, scanning electron microscopy and Vickers hardness testing. The alloys exhibit quite simple FCC and BCC solid solution phases. Co, Cu and Ni elements enhance the formation of the FCC phase while Al and Cr enhance that of the BCC phase in the alloy system. BCC phases form a spinodal structure during cooling. Copper tends to segregate at the interdendrite region and forms a Cu-rich FCC phase. Low copper content renders the interdendrite as a thin film and the as-cast structure like recrystallized grain structure. The formation of BCC phases significantly increases the hardness level of the alloy system. The strengthening mechanism is discussed. 相似文献
6.
Recent advances in the pharmacology of sedative drugs have expanded their use in the intensive care unit. Indications and endpoints for sedation, however, often are defined poorly and are difficult to assess. Nevertheless, the complications of sedative drug administration are real. New indications for sedation have been proposed in recent years, including enforcing sleep/wake cycles, manipulating cellular metabolism, and preventing myocardial ischemia. The evidence supporting the efficacy of these new indications is not yet complete. 相似文献
7.
Dielectric properties and conduction of the epoxy and its composites were measured over the temperature range — 20 to 70°C and the frequency range 10–4-10–1 Hz. Dielectric properties were obtained by performing Fouriertransforms on the charging and discharging curves. The resulting isothermal frequency spectra of dielectric constants and dielectric loss factors were analysed using the Cole-Cole law to obtain the activation energy for each material. The activation energies were also obtained for isothermal d.c. current. Current density-electric field-temperature characteristics are obtained for field levels up to 60 kV cm–1, with step excitation of the applied field and currents recorded after a delay time of 10 min. Current density and electric field were computed and plotted for constant temperature. The linear (ohmic) curves were obtained for fields up to about 60 kV cm–1 for temperatures up to about 20 °C. The non-linearity at the higher fields and temperatures did not imply the occurrence of non-ionic conduction. It has been demonstrated that both electric conduction and relaxation behaviour were ionic and could be fit by the Nakajima model for the unfilled epoxy and the Taylor model for the composites. 相似文献
8.
Autologous or glutaraldehyde treated bovine pericardial valved patch was utilized for widening of the right ventricular outflow tract in 20 patients with tetralogy of Fallot (autologous pericardium group in 10 patients and bovine pericardium group in 10). Pericardial valve function of the both materials was evaluated by postoperative cardiac catheterization performed 1 year after the operation. There were no significant differences in pulmonary arterial and right ventricular pressures, and right ventricular ejection fraction and end-diastolic volume between the 2 groups. Pulmonary angiogram in the autologous pericardium group patients demonstrated the pulmonary regurgitation (PR) of grade 1 in 5 patients, grade 2 in 4 and grade 3 in 1. On the other hand, 1, 3 and 6 patients in the bovine pericardium group demonstrated no-PR, grade 1 PR and grade 2 PR, respectively. It was concluded that there were no significant differences between autologous and glutaraldehyde treated bovine pericardium as a material of valved patch for widening of the right ventricular outflow tract of tetralogy of Fallot. 相似文献
9.
MODELING LIQUID MASS TRANSFER IN HIGEE SEPARATION PROCESS 总被引:1,自引:0,他引:1
Correspondence concerning this paper should be addressed to Professor Richard S.H. Mah. Hsien-Hsin Tung is now affiliated with Department of Chemical Engineering, California Institute of Technology
Penetration theory is used to describe the liquid mass transfer in Higee separation process. Within a possible range of effective areas, it is shown that the predicted mass transfer coefficients are in reasonable agreement with the estimated mass transfer coefficients. The estimated coefficients were calculated from the experimental data and the possible effective areas. Hence it is concluded the penetration theory is generally applicable to describe liquid mass transfer in Higee separation process. The comparison also suggests that liquid mixing at the junctions of packing materials may be more complete in Higee process than in traditional process. 相似文献
Penetration theory is used to describe the liquid mass transfer in Higee separation process. Within a possible range of effective areas, it is shown that the predicted mass transfer coefficients are in reasonable agreement with the estimated mass transfer coefficients. The estimated coefficients were calculated from the experimental data and the possible effective areas. Hence it is concluded the penetration theory is generally applicable to describe liquid mass transfer in Higee separation process. The comparison also suggests that liquid mixing at the junctions of packing materials may be more complete in Higee process than in traditional process. 相似文献
10.
OD Otuyemi VI Ugboko KC Ndukwe CA Adekoya-Sofowora 《Canadian Metallurgical Quarterly》1997,47(5):266-270
The mechanical stability of proximal femoral osteotomies fixed by the tension band wire technique was studied in flexion-compression and torsion tests. The fixation consisted in crossing the section with two Kirschner wires and with a wire cerclage applied to the tension surface. The study was conducted in three steps. First, cyclinders of wood were cut either transversely or at 30 degrees of inclination in relation to the long axis of the specimen, and fixed with two Kirschner wires and a wire cerclage. We concluded that the inclination of the plane of section significantly increased the stability of fixation. No significant difference was observed when oblique sections were made in the reverse orientation. Second, 30 degrees subtrochanteric varus osteotomies were performed in dog femurs, so that the section plane was transverse in one group and oblique in another, after closing the osteotomy. In both groups the fixation was achieved by two Kirschner wires that crossed the osteotomy and a wire cerclage placed on the lateral cortex (tension surface). We concluded that inclination of the osteotomy plane increased the stability of osteosynthesis in bone specimens, as already seen with the wood pieces. Third, the stability of tension band wire fixation was compared with that provided by the AO/ASIF paediatric angled plate. Varus osteotomies (30 degrees) were created at the subtrochanteric level of paired dog femurs. On one side, the femur was fixed with Kirschner wires and a wire cerclage as described previously. For the other femur, the osteotomy was fixed with the angled plate. We found that both types of fixation presented the same stability in flexion-compression tests. However, under torsion the tension band wire fixation was 30%-50% less stable than the plate fixation. 相似文献