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11.
OBJECTIVES: Adequate preparation of the bowel is essential for accurate colonoscopic examination. We compared colonic preparation with sodium picosulphate plus magnesium citrate (SPS-Mg) with sulphate-free polyethylene glycol electrolyte lavage (PEG-EL) solution before colonoscopy, for quality of bowel cleansing, patient discomfort, and side effects. METHODS: Sixty-eight consecutive patients were randomly assigned to receive either 3 sachets of SPS-Mg (16.5 g each) (n = 39) or 3 L of PEG-EL (n = 29) on the day before colonoscopy. Shortly before the procedure each patient was interviewed to determine the degree of discomfort (1 = none or mild, 2 = moderate, 3 = severe) and side effects. The quality of bowel cleansing was graded by a gastroenterologist who was unaware of the method of preparation (from 1 = poor to 4 = excellent). RESULTS: Of the 29 PEG-EL patients, four (14%) did not complete the preparation because of side effects. The degree of discomfort was significantly greater with PEG-EL (mean score, 2.3 +/- 0.7) than with SPS-Mg (mean score, 1.4 +/- 0.5; p < 0.01). Nausea and vomiting were significantly more common in the PEG-EL group (38% vs 13%; p < 0.05). Using intention-to-treat analysis, bowel cleansing proved to be significantly better with SPS-Mg than with PEG-EL (mean score +/- SD, 3.05 +/- 0.9 and 2.57 +/- 1.0, respectively; p = 0.036). CONCLUSIONS: Colonic preparation with SPS-Mg is better tolerated, associated with significantly fewer side effects, and results in higher quality bowel cleansing than preparation with PEG-EL.  相似文献   
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Postevaluation (PE) of an information system is probably the most neglected activity along the system life cycle. However, PE is essential for making improvements to existing systems and generating standard practices for future information system development projects. Based on actual experience, the 12-step procedure described here can help organizations realize both the future and immediate benefits that PE offers.  相似文献   
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For the first time, to our knowledge, a highly robust, high-bit-rate (10 Gbit/s) wavelength converter that is based on a narrow Brillouin filter is reported. The conversion takes place in a semiconductor optical amplifier (SOA) in a cross-gain-phase process. The SOA operates in a weak-modulation mode, and the exiting signal undergoes a dc reduction with a narrow spectral filter. In our system we perform spectrally narrow filtering by using a long Brillouin grating.  相似文献   
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在尖端设计中,先进的工艺技术采用了无法完全用仿真模型描述的复杂时序问题模式,从而促使半导体厂商越来越依赖事后的硅设计验证方法和物理调试方法。在处理多个金属层互连工艺和先进的封装技术时,早期的物理调试方法遇到的挑战越来越多。然而,利用新的光学探测技术,设计工程师们可以  相似文献   
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We present a unique method for real-time polarization measurement by use of a discrete space-variant subwavelength grating. The formation of the grating is done by discrete orientation of the local subwavelength grooves. The complete polarization analysis of the incident beam is determined by spatial Fourier transform of the near-field intensity distribution transmitted through the discrete subwavelength dielectric grating followed by a subwavelength metal polarizer. We discuss a theoretical analysis based on Stokes-Mueller formalism, as well as on Jones calculus, and experimentally demonstrate our approach with polarization measurements of infrared radiation at a wavelength of 10.6 microm.  相似文献   
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The role of the males who are sexual partners of females with genital human papillomavirus (HPV) infection and premalignant lesions is explored in the present study. Within a period of 3 years, 391 females with genital premalignant and HPV-associated lesions were examined and treated at the Cervical Pathology Unit of the Tel Aviv Medical Center. The male partners of all the women were asked to attend this unit, and 322 of them responded. All participants underwent colposcopic examination of the anogenital area followed by colposcopically guided biopsies from the most representative lesions, when present, part of which included in situ hybridization (ISH) of HPV DNA sequences 6/11 and 16/18. The histological prevalence of HPV among the male partners was 86.6% (185 of 213 biopsies). Of the 48 couples who had ISH evaluations, the ISH could not identify any copy of HPV DNA in 58.3% of the males (28 cases) and 41.6% of the females (20 cases). Among the males, HPV 6/11 and 16/18 were found in 17 (35.4%) and 3 cases (6.2%), respectively, and among the females there were 23 (48.0%) and 5 cases (10.4%), respectively. Correlation of HPV DNA sequences 6/11 and 16/18 between the couples was found in six (12.5%) and in one (2.0%), respectively. These data do not support a direct contamination by the current male partner. The question of treating the male partner of a woman with genital HPV and premalignant lesions remains to be evaluated.  相似文献   
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OBJECTIVES: To investigate whether liver ischemia and reperfusion (IR) directly affect functions of remote organs. BACKGROUND: Cardiovascular and respiratory dysfunction follows hemorrhage, spinal shock, or trauma as a result of no-flow-reflow phenomena. Hepatic IR induces remote organ damage probably by xanthine oxidase and oxygen species. MATERIALS AND METHODS: Isolated rat livers, lungs, and hearts were perfused with Krebs-Henseleit solutions. After stabilization, livers were either perfused or made ischemic. Then, livers and hearts or livers and lungs were reperfused in series, and the liver was disconnected and the second organ continued to perfuse with the accumulated effluents. MEASUREMENTS AND MAIN RESULTS: Ischemic and reperfused liver effluent contained high lactate dehydrogenase and uric acid concentrations compared with controls; xanthine oxidase increased 60 to 100 times. Ischemic and reperfused lung peak inspiratory pressure almost doubled; airway static compliance halved; myocardial contractility decreased to 70% of baseline; wet weight-to-dry weight ratios of lungs and livers increased. CONCLUSION: Ischemic and reperfused liver can directly induce myocardial and pulmonary dysfunction, presumably by oxidant-induced injury.  相似文献   
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Cranberry constituents are known to exert anti-adhesion activity on H. pylori in vitro. To determine their possible additive effect to triple therapy with omeprazole, amoxicillin and clarithromycin (OAC), a double-blind randomized clinical study was carried out. One-hundred-seventy-seven patients with H. pylori infection treated with OAC for 1 week were randomly allocated to receive 250 mL of either cranberry juice (cranberry-OAC, n = 89) or placebo beverage (placebo-OAC, n = 88) twice daily and only cranberry juice or placebo beverage for the next 2 weeks. Treatment outcome was determined with the(13)C urea breath test ((13)C-UBT). An additional control group consisted of patients referred to the same center during the same period who were treated with OAC alone for 1 week (non-placebo-OAC, n = 712). Overall, the rate of H. pylori eradication ((13)C-UBT < 3.5) was 82.5%, with no statistically significant difference among the three arms. Analysis by gender revealed that for female subjects, the eradication rate was higher in the cranberry-OAC arm (n = 42, 95.2%) than in the placebo-OAC arm (n = 53, 86.8%) and significantly higher than in the non-placebo-OAC group (n = 425, 80%; p = 0.03). For males, the rate was nonsignificantly lower in the cranberry-OAC arm (n = 35, 73.9%) than in the placebo-OAC arm (n = 45, 80.0%) and non-placebo-OAC group (n = 287, 85.0%). These results suggest that the addition of cranberry to triple therapy improves the rate of H. pylori eradication in females.  相似文献   
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