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Temperament refers to children's behavioral style, or the manner in which they interact with their environment. Temperament has been quantified into nine temperament categories and five temperament constellations by Thomas and Chess. Temperament categories and constellations of children can be measured using one of several parental questionnaires, each of which focuses on age-appropriate behavior. For this study the Behavioral Style Questionnaire (BSQ) was administered to the parents of 50 healthy children (mean age 48.8 months) receiving initial dental examinations. The examinations were videotaped and The Ohio State Behavior Rating Scale (OSUBRS) was used to rate each child's behavior into one of four behavioral categories: 1) quiet; 2) crying only; 3) disruptive movement only; and 4) crying and disruptive movement. For data analysis the percentage duration of each behavioral category was calculated. Using one-way ANOVA, significant differences between constellations were found for quiet (P = 0.03) and combination behavior (P = 0.03). Using a stepwise linear regression, the temperament category of approach/withdrawal was found to predict the percentage of quiet (multiple R = 0.42357, R2 = 0.17941, and P = 0.002), crying (multiple R = 0.42124, R2 = 0.17744, and P = 0.002), and combination behaviors (multiple R = 0.30008, R2 = 0.09005, and P = 0.03). Additionally, significant regressions were found with temperament categories predicting behavioral categories depending on the child's age. The results of this pilot study suggest that the BSQ temperament constellations and categories appear to be modest predictors of a child's specific behaviors in the dental environment. Knowledge of a child's temperament may prepare the clinician to predict patient behaviors in the dental environment.  相似文献   
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An analysis of 944 cases of acute appendicitis treated at the University of Kentucky Medical Center from 1966 to 1973 is presented. There were 12 deaths in this series, a mortality rate of 1.3 per cent, and the clinical presentation, operative and autopsy findings are discussed. It is significant that seven of the 12 patients had other serious illnesses that influenced the decision for operation and that operation was delayed over 48 hours in 50 percent. It is stressed that the need for early exploration in the patient suspected of having appendicitis is even more imperative in the individual with concomitant disease. Adequate but immediate preoperative preparation with fluids and electrolytes antibiotics and stabilization of renal, pulmonary and cardiac status is mandatory.  相似文献   
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Periodontitis is a common, progressive disease that eventually affects the majority of the population. The local destruction of periodontitis is believed to result from a bacterial infection of the gingival sulcus, and several clinical studies have provided evidence to implicate Porphyromonas gingivalis. If P. gingivalis is a periodontal pathogen, it would be expected to be present in most subjects with disease and rarely detected in subjects with good periodontal health. However, in most previous studies, P. gingivalis has not been detected in the majority of subjects with disease, and age-matched, periodontally healthy controls were not included for comparison. The purpose of the study reported here was to compare the prevalence of P. gingivalis in a group with periodontitis to that of a group that is periodontally healthy. A comprehensive sampling strategy and a sensitive PCR assay were used to maximize the likelihood of detection. The target sequence for P. gingivalis-specific amplification was the transcribed spacer region within the ribosomal operon. P. gingivalis was detected in only 25% (46 of 181) of the healthy subjects but was detected in 79% (103 of 130) of the periodontitis group (P < 0.0001). The odds ratio for being infected with P. gingivalis was 11.2 times greater in the periodontitis group than in the healthy group (95% confidence interval, 6.5 to 19.2). These data implicate P. gingivalis in the pathogenesis of periodontitis and suggest that P. gingivalis may not be a normal inhabitant of a periodontally healthy dentition.  相似文献   
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Iron Mössbauer spectroscopy and X-ray diffraction methods were applied to the study of a selection of ashes produced in a Lurgi gasification plant and fly ash from a pulverized coal combustion. The ashes contained hematite, magnetite, and goethite. Sixty percent or more of the iron in these ashes was in the oxide form, with the remainder present in mullite and other silicate phases. Iron was divalent in the latter, and present as both Fe+2 and Fe+3 in mullite. Ratios of Fe+2 and Fe+3 varied from 0.3 to 0.7. By comparison, a water-quenched molten bottom ash was free of iron oxides and contained only amorphous silicate phases with virtually all iron in the divalent state.  相似文献   
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Population extinction is a fundamental biological process with applications to ecology, epidemiology, immunology, conservation biology and genetics. Although a monotonic relationship between initial population size and mean extinction time is predicted by virtually all theoretical models, attempts at empirical demonstration have been equivocal. We suggest that this anomaly is best explained with reference to the transient properties of ensembles of populations. Specifically, we submit that under experimental conditions, many populations escape their initially vulnerable state to reach quasi-stationarity, where effects of initial conditions are erased. Thus, extinction of populations initialized far from quasi-stationarity may be exposed to a two-phase extinction hazard. An empirical prediction of this theory is that the fit Cox proportional hazards regression model for the observed survival time distribution of a group of populations will be shown to violate the proportional hazards assumption early in the experiment, but not at later times. We report results of two experiments with the cladoceran zooplankton Daphnia magna designed to exhibit this phenomenon. In one experiment, habitat size was also varied. Statistical analysis showed that in one of these experiments a transformation occurred so that very early in the experiment there existed a transient phase during which the extinction hazard was primarily owing to the initial population size, and that this was gradually replaced by a more stable quasi-stationary phase. In the second experiment, only habitat size unambiguously displayed an effect. Analysis of data pooled from both experiments suggests that the overall extinction time distribution in this system results from the mixture of extinctions during the initial rapid phase, during which the effects of initial population size can be considerable, and a longer quasi-stationary phase, during which only habitat size has an effect. These are the first results, to our knowledge, of a two-phase population extinction process.  相似文献   
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Objective: To investigate the psychometric properties of the Community Integration Measure (CIM), a scale that assesses self-perceived quality of community integration, among persons with traumatic brain injury (TBI). Method: Persons (N = 279) with TBI completed the CIM, as well as other measures of community integration and quality of life, and were followed up to 15 years postinjury. Results: The CIM was found to be a reliable instrument with adequate internal consistency. Validity was demonstrated in its relationship to other measures of community integration and life satisfaction. Utility was evident in its prediction of perceived social support. Conclusion: Results suggest that the CIM is an adequate measure of community integration for persons with histories of TBI of up to 15 years. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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