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971.
The method pricing described is an attempt to formulate a practical but simple procedure for predicting construction costs. It can be applied in any developing country where characteristically there is very little reliable cost information. The objective is to maximise the accuracy of the price while minimising the estimating time and cost within the constraints of limited historical data.
The method involves classification into major and minor cost items and simple forecasting procedures for individual items and unit price. The procedure is illustrated with examples from Thailand using locally available data. 相似文献
972.
Monte Carlo methods were used to investigate the adequacy of 2 approaches to data analysis in a repeated measures design in which the number of repeated levels was large and the sample size was relatively small. The techniques examined were G. E. Box's (1954) ε?-adjustment and H. Huynh and L. S. Feldt's (1976) ε?-adjustment. Results show that approximate univariate approaches to repeated measures can successfully be used even when the number of Ss is smaller than the number of levels of the repeated factor. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
973.
BJ Harrison DP Symmons P Brennan CR Bankhead EM Barrett DG Scott AJ Silman 《Canadian Metallurgical Quarterly》1996,23(8):1326-1331
OBJECTIVE: To predict which patients with early inflammatory polyarthritis presenting to primary care will be functionally disabled one year after presentation, in order to inform treatment and referral decisions. METHODS: The study population consisted of 381 patients notified to the Norfolk Arthritis Register, a primary care based inception cohort of patients with inflammatory polyarthritis. Patients were regarded as functionally disabled if they had a Health Assessment Questionnaire (HAQ) score of one or more. Clinical, laboratory, and demographic variables easily measured at baseline were analyzed for their ability to predict future disability. Recursive partitioning was used to create a simple decision tree to predict those patients who would be disabled at one year. A logistic regression model was generated on a sample of 277 patients and tested on an independent sample of 104 patients. This was compared with other models, one of which consisted of the 1987 ARA criteria. RESULTS: 112 (29%) patients had a HAQ score of at least 1 at one year. The strongest predictors of future disability were a high baseline HAQ, large joint involvement, female sex, and longer disease duration. The decision tree predicted disability accurately in 67% of patients. CONCLUSION: It is possible to predict functional outcome at one year among patients with early inflammatory polyarthritis presenting to primary care using simple clinical variables measured at baseline. Satisfying the 1987 ARA criteria could not be used to predict future disability. 相似文献
974.
F B Scott 《Medical instrumentation》1988,22(4):174-181
Urinary incontinence, the inability to retain urine, creates a misery that cannot be overestimated. The foul odor emanating from the patient repels family and friends to such an extent that it affects the social life of the sufferer. Total incontinence, that is, the continuous loss of urine as opposed to the loss associated with coughing or sneezing, is the most severe type of the malady. For such individuals, the artificial sphincter offers hope for a new life. Incidences of total urinary incontinence as a result of radical prostatectomy in the treatment of carcinoma of the prostate have been reported in the range of 5-50%. Incontinence may occur as a result of injury to the proximal urethra, and it is usually present to some extent in patients with neurogenic bladder dysfunction caused by spinal cord injury, myelomeningocele, or other conditions that affect the micturition centers of the nervous system. Some patients whose urinary tract is completely obstructed and who are therefore unable to urinate, as for example individuals who sustain traumatic complete transection of the urethra with resulting obstructive fibrosis of the urethra, or those patients whose neurogenic spastic sphincter inhibits satisfactory voiding, may benefit from reconstructive surgery or ablation of their pathologic sphincter in order to restore urination. Rehabilitation of such patients can then be complete with implantation of an artificial sphincter to provide urinary control. The alternatives for management include diapers, the placement of external collecting or occlusive devices, or major surgery in which the intestinal tract is used either for conducting the urine to an abdominal collecting bag or as a bladder substitute that is periodically emptied by catheterization.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
975.
PR Mahone K Scott G Sleggs T D'Antoni JR Woods 《Canadian Metallurgical Quarterly》1994,171(2):465-469
OBJECTIVE: Cocaine and metabolites can be found in the amniotic fluid after maternal use, presumably as a result of fetal urination. The fetus may be repeatedly exposed to the effects of these drugs through contact with amniotic fluid that contains these substances. The purpose of this study was to determine whether the naive fetal lamb generates detectable fetal blood levels of cocaine and metabolites when cocaine is placed directly into the amniotic fluid and, if so, whether fetal swallowing accounts for these findings. STUDY DESIGN: Six pregnant ewes with singleton fetuses of 120 to 125 days' gestation were chronically catheterized for daily sampling of cocaine and metabolite levels in maternal venous plasma, fetal venous plasma, and amniotic fluid over a 7-day period. Esophageal ligation was performed in three additional animals similarly instrumented to evaluate the role of fetal swallowing in the distribution of amniotic fluid cocaine and its metabolites. In each case, at the time of surgery, an Alzet osmotic pump delivering cocaine at 0.5 mg/kg estimated fetal weight per hour into the amniotic fluid was secured to the fetal back. Cocaine and metabolites (benzoylecgonine, ecgonine methyl ester, and norcocaine) were measured daily in material and fetal plasma, amniotic fluid, and meconium by solid-phase extraction and derivatization and quantified by high-performance gas chromatographic techniques. RESULTS: The concentrations of ecgonine methyl ester were highest in the amniotic fluid followed by cocaine and benzoylecgonine. In the normal and esophagus-ligated groups, cocaine, benzoylecgonine, and norcocaine were found in fetal plasma in concentrations of approximately 3% that of amniotic fluid. Ecgonine methyl ester was not detected in fetal plasma from either group. Meconium samples from sheep with and without esophageal ligation demonstrated high levels of norcocaine. CONCLUSION: We conclude that cocaine and metabolites in amniotic fluid enter the fetal circulation to produce detectable plasma levels through routes other than swallowing. Moreover, the results of meconium analyses in the two groups of fetuses suggest that fetal swallowing is not the primary mechanism by which cocaine and metabolites enter the intestine. 相似文献
976.
A model for predicting the incidence rate of carpal tunnel syndrome (CTS) for a given job, was developed using known biomechanical data, mechanical properties of human tendons and reliability engineering techniques to simplify the problem. In addition, time-dependent stress-strength interference theory was used to quantify the stress on the tendons during a job cycle, based on wrist position and grip strength and to estimate the tendon failure rate (or CTS incidence) for a given job. Higher failure probabilities were predicted for greater wrist deviations, for higher grasp forces, for females as compared to males, for wrist extension as compared to wrist flexion, and for two-fingered pinches as compared to four-fingered grasps. The predictions closely matched previously reported CTS incidence rates for a poultry thigh boning task. 相似文献
977.
TNF participates in the induction of nitric oxide (NO) production and macrophage activation, leading to the elimination of intracellular pathogens. We previously found that TNF receptor p55-deficient mice (TNFRp55-/-) control replication of Leishmania major in vivo but fail to resolve their lesions. Here we report that mice lacking the p75 receptor (TNFRp75-/-) or both receptors (TNFRp55p75-/-), also control parasite replication, albeit mice lacking the p55 receptor (either TNFRp55-/- or TNFRp55p75-/-) are delayed in their elimination of L. major compared with controls. All TNF receptor-deficient mice developed a Thl-type immune response and up-regulated inducible NO synthase (iNOS) mRNA gene expression in lesions during infection. Thus, neither TNF receptor appears to be absolutely required for NO production or elimination of L. major in vivo. In vitro, however, while macrophages from naive TNFRp75-/- mice could be activated to produce NO and kill L. major, we observed a defect in NO production and parasite killing by resident peritoneal macrophages from naive TNFRp55-/- or TNFRp55p75-/- mice. However, when macrophages were elicited with leishmanial Ag from 4-wk-infected TNFRp55-/- or TNFRp55p75-/- mice, they produced NO and were leishmanicidal. These data suggest that the TNFRp75 plays no essential role in L. major infection in mice and that the p55 receptor may be required for optimal macrophage activation. However, the results also show that a mechanism exists by which macrophages can be primed in vivo during L. major infection to produce NO and kill L. major in the absence of signaling through either of the TNF receptors. 相似文献
978.
SR Cummings DM Black DE Thompson WB Applegate E Barrett-Connor TA Musliner L Palermo R Prineas SM Rubin JC Scott T Vogt R Wallace AJ Yates AZ LaCroix 《Canadian Metallurgical Quarterly》1998,280(24):2077-2082
CONTEXT: Alendronate sodium reduces fracture risk in postmenopausal women who have vertebral fractures, but its effects on fracture risk have not been studied for women without vertebral fractures. OBJECTIVE: To test the hypothesis that 4 years of alendronate would decrease the risk of clinical and vertebral fractures in women who have low bone mineral density (BMD) but no vertebral fractures. DESIGN: Randomized, blinded, placebo-controlled trial. SETTING: Eleven community-based clinical research centers. SUBJECTS: Women aged 54 to 81 years with a femoral neck BMD of 0.68 g/cm2 or less (Hologic Inc, Waltham, Mass) but no vertebral fracture; 4432 were randomized to alendronate or placebo and 4272 (96%) completed outcome measurements at the final visit (an average of 4.2 years later). INTERVENTION: All participants reporting calcium intakes of 1000 mg/d or less received a supplement containing 500 mg of calcium and 250 IU of cholecalciferol. Subjects were randomly assigned to either placebo or 5 mg/d of alendronate sodium for 2 years followed by 10 mg/d for the remainder of the trial. MAIN OUTCOME MEASURES: Clinical fractures confirmed by x-ray reports, new vertebral deformities detected by morphometric measurements on radiographs, and BMD measured by dual x-ray absorptiometry. RESULTS: Alendronate increased BMD at all sites studied (P<.001) and reduced clinical fractures from 312 in the placebo group to 272 in the intervention group, but not significantly so (14% reduction; relative hazard [RH], 0.86; 95% confidence interval [CI], 0.73-1.01). Alendronate reduced clinical fractures by 36% in women with baseline osteoporosis at the femoral neck (>2.5 SDs below the normal young adult mean; RH, 0.64; 95% CI, 0.50-0.82; treatment-control difference, 6.5%; number needed to treat [NNT], 15), but there was no significant reduction among those with higher BMD (RH, 1.08; 95% CI, 0.87-1.35). Alendronate decreased the risk of radiographic vertebral fractures by 44% overall (relative risk, 0.56; 95% CI, 0.39-0.80; treatment-control difference, 1.7%; NNT, 60). Alendronate did not increase the risk of gastrointestinal or other adverse effects. CONCLUSIONS: In women with low BMD but without vertebral fractures, 4 years of alendronate safely increased BMD and decreased the risk of first vertebral deformity. Alendronate significantly reduced the risk of clinical fractures among women with osteoporosis but not among women with higher BMD. 相似文献
979.
Simonik Diane K.; Robinson Scott R.; Smotherman William P. 《Canadian Metallurgical Quarterly》1994,108(6):1179
Rat fetuses were exposed to cocaine, lidocaine, or saline on Gestational Day 20 or 21 to provide information about cocaine effects on behavior during prenatal development. Cocaine was administered into the cisterna magna of individual fetal subjects to restrict effects to the CNS. Behavioral effects of cocaine were compared with lidocaine to help distinguish the effects of cocaine on monoamine systems in the brain from its properties as a local anesthetic. Cocaine promoted 3–5 fold increases in fetal motor activity in the absence of explicit sensory stimulation, in contrast to the slight suppressive effects of lidocaine. Cocaine and lidocaine also reduced coordinated behavioral responses to an artificial nipple. The behavioral effects of cocaine administered into the CNS of fetal subjects suggest specific mechanisms of action on developing neural and behavioral systems in the late prenatal period. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
980.