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PURPOSE: This study was undertaken to compare postoperatively laparoscopic (LAR) with open (OAR) anterior resection in patients with rectosigmoid cancers. METHODS: Forty consecutive patients were divided into two groups: 20 patients (9 males) were allocated to LAR and 20 patients (6 males) to OAR. RESULTS: Median age in the LAR group was 62 (range, 39-77) years, and in the OAR group, it was 61 (range, 43-84) years (P = 0.9). Median lengths of the distal margin of clearance beyond the tumor were 4 (range, 2-8) cm and 4.5 (range, 3-7.5) cm in the LAR and OAR groups, respectively (P = 0.35). Median numbers of lymph nodes harvested were 20 (range, 7-49) and 19 (range, 7-97) for the LAR and OAR groups, respectively (P = 0.44). Median operating times were 90 (range, 55-185) minutes and 73 (range, 40-140) minutes in the LAR and OAR groups, respectively (P = 0.08). Blood losses were 50 (range, 50-800) ml and 50 (range, 50-1,500) ml in the LAR and OAR groups, respectively. There was no intraoperative complication in either group, and no laparoscopic patient was converted to an open procedure. Median length of extraction site incision in the LAR group was 5.5 (4-13) cm, and length of incision in the OAR group was 18 (8-25) cm (P < 0.002). CONCLUSION: There were no significant differences between the two groups with regard to duration of parenteral analgesia, starting of fluid and solid diet after surgery, or time to first bowel movement and time to discharge from the hospital. 相似文献
994.
A multifunctional [60]fullerene derivative AEAF was melt-mixed with poly(ethylene-co-acrylic acid) (PEAA20). The strong interaction between AEAF and PEAA20, as shown by x-ray photoelectron spectroscopy, enables AEAF to be well dispersed in the amorphous phase of PEAA20. WAXD revealed that the crystallinity of PEAA20 is reduced and the crystallites are deformed by the addition of AEAF. The storage modulus and dynamic glass transition temperature of the polymer increase upon the incorporation of AEAF. Unlike C60 and a monofunctional C60 derivative, AEAF is able to sustain its reinforcing effect in the glass-rubber transition region. 相似文献
995.
996.
997.
Theoretical considerations for the development of a simplified model for predicting volatilization losses of ammonia gas (NH3(g)) from the urine patches of grazing herbivores in a pasture ecosystem are presented. The volatilization of NH3(g) is treated as a physico-chemical phenomenon based on the soil solution chemistry of urine patches to develop a general equation to describe the rate of volatilization from a pasture surface. A semi-empirical approach was then used in which published data define typical limits for the parameters appearing in the volatilization equation. This led to the simplification of the general volatilization equation into a more useable and more readily verifiable form.The dominant factor in determining the rate of volatilization of NH3(g) was shown to be the soil surface pH. To better understand the dynamics of pH changes within urine patches, the more extensive literature dealing with volatilization losses from flooded soils was reviewed. From the apparent similarities between the two systems a procedure was described by which a careful monitoring of soil surface pH as a function of time could be used to solve the simplified equation.To calculate NH3(g) fluxes this model requires the following as input data: a knowledge of the disposition of the applied-N within the soil profile; the rate of urea hydrolysis in the topsoil; and soil surface pH and temperature measurements throughout the duration of a volatilization event. 相似文献
998.
WC Roesch 《Canadian Metallurgical Quarterly》1977,70(3):494-510
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1000.
Quality assurance programs have been established during the last two decades in developed countries to promote high quality performance in clinical laboratories. In Taiwan, such a program for clinical microbiology laboratories has been in place since July 1987. It has been supported by the Department of Health, Executive Yuan, R.O.C. and was set up by the authors. The manpower status, facilities and equipment, and performance of clinical laboratories were investigated during the first year and standards of laboratory quality were recommended. Since then, under a continuing education program, we have conducted seminars, symposia, workshops, short-courses or panel discussions approximately 4 times a year. There have been about 150 participants per session and they have come from local hospitals (primary care hospitals), regional hospitals (secondary care hospitals) and medical centers (tertiary care hospitals). Proficiency test specimens or external unknown specimens were sent to all the laboratories twice a year and approximately 3 specimens were used each time for the evaluation of each laboratory's diagnostic capability and quality of service. Results indicated that there were tremendous improvements in the quality of laboratory performance. At the same time, several laboratory manuals describing the methods of quality control of clinical specimens, test procedures, media and reagents, personnel management and a compilation of reports etc. were published as guidelines of basic requirements for each level of the laboratories. For local hospital laboratories in remote areas, several regional hospitals or medical centers with high quality laboratories were selected to serve as back-ups. Our evaluation has shown that the performance and quality of service provided by most clinical microbiology laboratories in Taiwan have now reached nearly the level of those found in the so-called "developed countries". 相似文献