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991.
In recent years, expert systems technology has been recognized as a way of improving managerial and organizational effectiveness. Most of the related literature available has been introductory in nature or has focused on only one aspect of expert systems development. This article presents a more global organizational view of expert systems to help MIS managers select the most appropriate expert systems applications for their organization 相似文献
992.
OBJECTIVE: To evaluate the frequency of human papillomavirus (HPV) 16 and 18 infection in patients with different grades of cervical intraepithelial neoplasia (CIN). METHOD: Five-hundred and five patients with CIN, referred for conization, were included in this study. Before conization, cytological material for in situ hybridization was obtained from the uterine cervix to detect the presence of HPV 16 and 18 infection. RESULT: Among all patients with CIN, 82 (16.2%) were solely HPV 16 and 51 (10.1%) were solely HPV 18 positive. There were 133 patients (26.3%) positive for HPV 16 or HPV 18 and 31 patients (6.1%) were positive for both viral types, giving an overall HPV 16/18 infection rate of 32.4%. There were 15 (55.5%) HPV 16 or HPV 18 positive patients with CIN 1, 45 (33.8%) HPV 16 or HPV 18 positive patients with CIN 2 and 104 (30.2%) HPV 16 or HPV 18 positive patients with CIN 3. CONCLUSION: In patients with CIN 1, HPV 16 and 18 infection was more frequent than in patients with CIN 2, but the difference was not significant. Patients with CIN 2 were infected slightly more frequently, but not significantly, than patients with CIN 3. On the other hand, patients with CIN 1 were significantly more frequently infected than patients with CIN 3. 相似文献
993.
994.
M Goh CG Kleer P Kielczewski KJ Wojno K Kim JE Oesterling 《Canadian Metallurgical Quarterly》1997,49(4):569-73; discussion 574
OBJECTIVES: To determine if autologous blood donation prior to anatomical radical retropubic prostatectomy, given current improvements in surgical technique, is necessary. METHODS: The medical records of 200 consecutive patients undergoing radical retropubic prostatectomy for clinically localized prostate cancer were reviewed with regard to (1) preoperative hematocrit (HCT); (2) estimated blood loss (EBL); (3) postoperative HCT prior to discharge; (4) number of units of autologous blood donated; and (5) number of units of autologous and homologous blood transfused. In addition, the charges associated with autologous blood donation were determined via telephone interview with 14 blood donation centers across the United States. RESULTS: Overall, 189 patients (95%) did not require a homologous blood transfusion. Sixty-four patients (32%) donated autologous units and 136 patients (68%) did not. Of the patients who had donated, only 17 (27%) received their blood back, and none (0%) received any homologous blood. Eleven (8%) of the 136 nondonors received a blood transfusion. The autologous donors, in comparison with nondonors, were found to have a significantly lower preoperative HCT (mean +/- standard deviation: 40 +/- 4.0% versus 42 +/- 2.9%, P < 0.05). However, there was no statistically significant difference in the mean EBL between the two groups, autologous donors versus nondonors (771 +/- 370 versus 737 +/- 425 cc, P = 0.23). The autologous donors had a smaller mean change in HCT versus the nondonors (-9.3 +/- 5.1% versus -11.2 +/- 4.4%, P < 0.05), reflecting an increased willingness to transfuse patients who have autologous units available. With regard to cost, patients, on average, can expect to be charged as much as $745 per unit of autologous blood donated. CONCLUSIONS: These findings suggest that preoperative blood donation prior to radical prostatectomy may not be necessary, because 95% of the patients did not require a homologous blood transfusion. In addition, autologous blood donation can be associated with substantial costs in both time and money. Thus, autologous donation should be left as an option for the patient and should not be considered routine practice. 相似文献
995.
Summary Poly(N-vinyl pyrrolidone) (PVPr) forms miscible binary blends with poly(hydroxyethyl methacrylate), poly(hydroxypropyl methacrylate)
and two styrene/allyl alcohol copolymers, as shown by their glass transition behavior. However, PVPr is immiscible with poly(ethyl
methacrylate), poly(n-propyl methacrylate) and polystyrene. The results indicate the importance of hydroxyl groups in achieving
miscibility. 相似文献
996.
Goh C.S. Set S.Y. Taira K. Khijwania S.K. Kikuchi K. 《Photonics Technology Letters, IEEE》2002,14(5):663-665
In this letter, we demonstrate an adjustable dispersion slope compensator for waveform distortion compensation based on a nonlinearly strain-chirped fiber Bragg grating. The dispersion slope of the device can be tuned up to -18.9 ps/nm2 with a bandwidth >2.4 nm. After transmission through a 120-km-long dispersion-shifted fiber, the resulting waveform distortion for a 2.65-ps pulse is successfully compensated by using this device 相似文献
997.
The latest progress in RF plasma anodisation of SiGe alloys at 80°C is reported. Compared with the authors' previous results, considerable improvement in interfacial quality has been achieved. However, unlike the thermally grown samples. No negative fixed oxide charges were found 相似文献
998.
H. W. Ouyang J. C. H. Goh X. M. Mo S. H. Teoh E. H. Lee 《Materials science & engineering. C, Materials for biological applications》2002,20(1-2):63-69
In this study, the adhesion, proliferation and morphology of rabbit anterior cruciate ligament (ACL) cells and bone marrow stromal cells (bMSCs) on synthetic biodegradable polymeric films were investigated. Tissue culture polystyrene (TCP) was used as control. Seven biodegradable polymers were used; they are as follows: poly(-caprolactone) (PCL), poly(
-lactide) (
-PLA), poly(
-lactide) (
-PLA), PLA/PCL (50:50), PLA/PCL (75:25), high molecular weight (HMW) poly(
-lactide–co-glycolide (PLGA50:50) and HMW PLGA75:25. Polymeric film substrates were manufactured using solvent spin-casting technique. After 8 h of cell culture, a high percentage of ACL cells was found attached to PLGA50:50 (38.6±8.4%) and TCP (39.3±6.1%) as compared to the other six polymeric films (p≤0.001). As for bMSCs, 76.4±10%, 76.3±16% and 76.1±19% of seeded bMSCs were adhered to TCP, PLGA50:50 and PLGA75:25, respectively. These were significantly more than those of the other five polymeric films (p<0.001). At Day 5, bMSCs were found to proliferate faster on TCP (by 7±0.8-fold of initial cell seeding number),
-PLA (by 5.6±1.6-fold), PLGA50:50 (by 9.3±1.3-fold) and PLGA75:25 (by 5.8±1.3-fold) than on PCL, PLLA and PCL/PLA (50:50, 25:75) (p<0.001). ACL cells had a greater fold expansion on TCP (by 3.5±0.2-fold), PLGA50:50 (by 3.1±0.4-fold) and PLGA75:25 (by 3.9±0.4-fold) than on the other five polymer substrates (p<0.001). From these results, HMW PLGA (50:50, 75:25) was shown more likely to allow bMSCs and ACL cells to attach and proliferate, and bMSCs attached and proliferated faster than ACL cells. 相似文献
999.
Control charts are widely used for process monitoring in the manufacturing industry. Little research is available on their use to monitor the failure process of components or systems, which is important for equipment performance monitoring. Some Shewhart control charts, especially those for the number of defects, can be used for monitoring the number of failures per fixed interval; however, they are not effective especially when the failure frequency becomes small. A recent control scheme based on the cumulative quantity between observations of defects has been proposed which can be easily adopted to monitor the failure process for exponentially distributed inter-failure time. An investigation of its use for reliability monitoring is presented in this paper and the scheme can be easily extended to monitor inter-failure times that follow other distributions such as the Weibull distribution. Furthermore, the scheme is extended to the monitoring of time required to observe a fixed number of failures. The advantages of this scheme include the fact that the scheme does not require any subjective sample size, can be used for both high and low reliability items and can detect process improvement even in a high-reliability environment. 相似文献
1000.
Analysis of cholesterol and desmosterol in cultured cells without organic solvent extraction 总被引:1,自引:0,他引:1
Cultured cell sterols such as cholesterol and desmosterol are usually extracted into organic solvents before they are quantified
with cholesterol esterase and oxidase. A method to quantify these cultured cell sterols using cholesterol enzymes without
prior organic solvent extraction is described. In this method, a suspension or monolayer of cultured L-M, U-937, or PC-12
cells is digested with 0.1% sodium dodecyl sulfate (SDS), and the digest treated with microbial cholesterol enzymes. The quantity
of oxidized sterols produced by the reaction can be measured easily with high-pressure liquid chromatography, when a mixture
of sterols is present, or by the production of hydrogen peroxide when only one sterol is present. This method is easier and
safer to use than solvent extraction and can greatly expedite the quantitation of cultured cell sterols. Preliminary data
show that other lipids such as choline phospholipids, triglycerides, and fatty acids can also be directly quantified in SDS
cell digest by using specific enzymes to transform these lipids into hydrogen peroxides. 相似文献