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991.
992.
Economic analysis has so far said little about how an individual''s cognitive skills (CS) are related to the individual''s economic preferences in different choice domains, such as risk taking or saving, and how preferences in different domains are related to each other. Using a sample of 1,000 trainee truckers we report three findings. First, there is a strong and significant relationship between an individual''s CS and preferences. Individuals with better CS are more patient, in both short- and long-run. Better CS are also associated with a greater willingness to take calculated risks. Second, CS predict social awareness and choices in a sequential Prisoner''s Dilemma game. Subjects with better CS more accurately forecast others'' behavior and differentiate their behavior as a second mover more strongly depending on the first-mover''s choice. Third, CS, and in particular, the ability to plan, strongly predict perseverance on the job in a setting with a substantial financial penalty for early exit. Consistent with CS being a common factor in all of these preferences and behaviors, we find a strong pattern of correlation among them. These results, taken together with the theoretical explanation we offer for the relationships we find, suggest that higher CS systematically affect preferences and choices in ways that favor economic success.  相似文献   
993.
Background: Dreaming during anesthesia is not a well-understood phenomenon. Anticholinergic drugs are used in anesthesia as premedication, but their use to decrease the incidence of dreams and psychological adverse reactions after anesthesia is not well established. The authors therefore studied the efficacy of intramuscular atropine and scopolamine for the prevention of dreams during general anesthesia with propofol and nitrous oxide.

Methods: Healthy women undergoing minor gynecologic surgery were randomly assigned to receive 2.5 [mu]g/kg scopolamine or 10 [mu]g/kg atropine intramuscularly (n = 50/group). In both groups, anesthesia was induced and maintained with propofol as a 2.5-mg/kg bolus, followed by 12 mg [middle dot] kg-1 [middle dot] h-1 as a continuous infusion and 70% nitrous oxide in oxygen. Two interviews regarding dreaming activity and characteristics were conducted at 20 min and 6 h after surgery.

Results: None of the patients in the scopolamine group and 47% of the patients in the atropine group reported the occurrence of dreams 20 min after recovery. The results were similar at 6 h: 6% of the scopolamine group and 43% of the atropine group reported dream activity. No differences in sedation or anesthetic requirements were found.  相似文献   

994.
Recent studies have shown a genetic association between glucocerebrosidase deficiencies and Parkinson's disease (PD). To further explore this issue the activity of beta-glucocerebrosidase and the activities of other lysosomal enzymes, alpha-mannosidase, beta-mannosidase, beta-hexosaminidase, and beta-galactosidase have been evaluated in the cerebrospinal fluid (CSF) of PD patients. The activities of alpha-mannosidase, beta-mannosidase, beta-glucocerebrosidase, and beta-hexosaminidase were substantially decreased in the CSF of PD patients, while levels of beta-galactosidase were essentially identical to controls. This study indicates that in PD several lysosomal hydrolases have decreased activities, further supporting a possible link between pathophysiological mechanisms underlying PD and lysosomal hydrolases.  相似文献   
995.
Abstract: Purpose of this study was to evaluate the accuracy of mammography, ultrasonography, and magnetic resonance imaging (MRI), in the detection of breast implant rupture and to make a correlation with findings at explantation. The study population consisted of 63 women with 82 implants, undergoing surgical explantation. Implant rupture status was blindly determined obtaining diagnosis of rupture, possible rupture, or intact implant. Strictly predetermined rupture criteria were applied and compared with findings at surgery, which were considered the gold standard. False‐positives and false‐negatives were retrospectively evaluated to identify pitfalls in the investigation. All associations between imaging signs and surgical findings were evaluated by using chi‐square test. The respective sensitivity and specificity of investigations are reported. Our experience suggests that MRI is the more accurate method for identification of breast implant rupture, even if it should be performed following the diagnostic algorithm proposed.  相似文献   
996.
PURPOSE: The authors review 5 years of clinical experience using Straumann Orthosystem (Straumann, Basel, Switzerland) palatal mini-implants for orthodontic anchorage, describe clinical procedures, and give statistical results. MATERIALS AND METHODS: Diagnostic planning, surgical phase, and clinical procedure are described. The diagnostic planning was performed on lateral cephalogram in 13 cases; in 1 case, with an ectopically included upper canine, a computed tomography was requested. The Straumann Orthosystem kit includes a pure titanium implant with the healing cap, and a set of burs and instruments for the surgical insertion and removal. The sample comprised 14 adult patients (2 males and 12 females) requiring fixed orthodontic appliance for Class II malocclusion. Because of critical anchorage conditions they had received a palatal mini-implant as absolute anchorage during orthodontic treatment: 9 implants of 6.0 mm and 7 implants of 4.0 mm were positioned, primarily using a 2.5 mm transmucosal neck length. The orthodontic phase always started after 13 weeks of the insertion, in order to ensure osteointegration. RESULTS: In all cases, neither a perforation of the nasal cavity nor other surgical complication occurred. All implants have been successfully osteointegrated, except for 1 which has been lost for critical hygiene conditions. Two implants needed to be replaced because of tongue forces, which had been determined to interfere with the osteointegration immediately after surgery; this inconvenience was afterwards solved by the use of a resin splint. CONCLUSIONS: Palatal mini-implants revealed to be clinically easy to use and proved to be an efficient auxiliary device in orthodontics when absolute anchorage is needed.  相似文献   
997.
BACKGROUND: Chronic kidney diseases (CKD) tend to progress to end-stage renal failure (ESRF). As it has been demonstrated that angiotensin-converting enzyme inhibitors (ACEi) have a renoprotective effect in adults with proteinuric disease and may be effective in reducing hyperfiltration and proteinuria, they are also frequently used as anti-progression agents in paediatric patients with CKD despite the lack of data confirming their role in the nephropathies peculiar to children. The aim of this study was to investigate whether patients with hypodysplastic CKD (the most common cause of ESRF in children) treated with ACEi show a significantly slower decline in creatinine clearance (Ccr). METHODS: The analysis was based on the information available in the database of the ItalKid Project, a nationwide, population-based registry of chronic renal insufficiency (CRI) in children in Italy. Of the 822 patients with CRI due to hypodysplasia, we selected those who had been continuously treated with ACEi; the control patients were identified from the same diagnostic group and matched for gender, age and baseline Ccr. RESULTS: Progression was analysed as the slope of Ccr in a total of 164 patients: 41 cases and 123 matched controls. There were no significant between-group differences in blood pressure, duration of follow-up or pre-study slope of Ccr (-0.31+/-2.26 vs -0.33+/-3.58 ml/min/1.73 m2/year; P=NS). After an average of 4.9+/-2.3 years, the mean slope of Ccr was 40% lower in the ACEi-treated cases in comparison to controls (-1.08+/-2.08 vs -1.80+/-4.42 ml/min/1.73 m2/year), however, this difference was not statistically significant (P=0.31). CONCLUSIONS: We conclude that ACEi treatment does not significantly modify the naturally progressive course of hypodysplastic nephropathy in children and further studies are necessary before such treatment is routinely proposed for anti-progression purposes in children with CKD.  相似文献   
998.
999.
Since the fall of the Berlin Wall, fundamental political changes in eastern Europe have affected the Soviet-style health care systems that formerly provided basic care for everyone. Many of these systems have collapsed, and the new systems of social insurance that have replaced them often are inadequate. Advanced Training in Reproductive Health in Romania aimed to create an authority in family planning and reproductive health in selected Romanian university centers and to improve training and research capabilities. Initially, the project had 2 main goals: to provide advanced training in reproductive health and family planning to Romanian obstetrics-gynecology specialists from the main university centers-which would allow them to train other physicians (obstetricians, gynecologists, and general practitioners) and medical students-and to develop, test, and finalize specific training materials in Romanian to be used by the new trainers.  相似文献   
1000.
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