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排序方式: 共有109条查询结果,搜索用时 203 毫秒
1.
Hyperglycemia is a common condition in critically ill patients admitted to an intensive care unit (ICU). These patients represent an inhomogeneous collective and hyperglycemia might need different evaluation depending on the underlying disorder. To elucidate this, we investigated and compared associations of severe hyperglycemia (>200 mg/dL) and mortality in patients admitted to an ICU for acute myocardial infarction (AMI) or sepsis as the two most frequent admission diagnoses. From 2006 to 2009, 2551 patients 69 (58–77) years; 1544 male; 337 patients suffering from type 2 diabetes (T2DM)) who were admitted because of either AMI or sepsis to an ICU in a tertiary care hospital were investigated retrospectively. Follow-up of patients was performed between May 2013 and November 2013. In a Cox regression analysis, maximum glucose concentration at the day of admission was associated with mortality in the overall cohort (HR = 1.006, 95% CI: 1.004–1.009; p < 0.001) and in patients suffering from myocardial infarction (HR = 1.101, 95% CI: 1.075–1.127; p < 0.001) but only in trend in patients admitted to an ICU for sepsis (HR = 1.030, 95% CI: 0.998–1.062; p = 0.07). Severe hyperglycemia was associated with adverse intra-ICU mortality in the overall cohort (23% vs. 13%; p < 0.001) and patients admitted for AMI (15% vs. 5%; p < 0.001) but not for septic patients (39% vs. 40%; p = 0.48). A medical history of type 2 diabetes (n = 337; 13%) was not associated with increased intra-ICU mortality (15% vs. 15%; p = 0.93) but in patients with severe hyperglycemia and/or a known medical history of type 2 diabetes considered in combination, an increased mortality in AMI patients (intra-ICU 5% vs. 13%; p < 0.001) but not in septic patients (intra-ICU 38% vs. 41%; p = 0.53) could be evidenced. The presence of hyperglycemia in critically ill patients has differential impact within the different etiological groups. Hyperglycemia in AMI patients might identify a sicker patient collective suffering from pre-diabetes or undiagnosed diabetes with its’ known adverse consequences, especially in the long-term. Hyperglycemia in sepsis might be considered as adaptive survival mechanism to hypo-perfusion and consecutive lack of glucose in peripheral cells. AMI patients with hyperglycemic derailment during an ICU-stay should be closely followed-up and extensively screened for diabetes to improve patients’ outcome.  相似文献   
2.
The combined use of global positioning system (GPS) technology and motion sensors within the discipline of movement ecology has increased over recent years. This is particularly the case for instrumented wildlife, with many studies now opting to record parameters at high (infra-second) sampling frequencies. However, the detail with which GPS loggers can elucidate fine-scale movement depends on the precision and accuracy of fixes, with accuracy being affected by signal reception. We hypothesized that animal behaviour was the main factor affecting fix inaccuracy, with inherent GPS positional noise (jitter) being most apparent during GPS fixes for non-moving locations, thereby producing disproportionate error during rest periods. A movement-verified filtering (MVF) protocol was constructed to compare GPS-derived speed data with dynamic body acceleration, to provide a computationally quick method for identifying genuine travelling movement. This method was tested on 11 free-ranging lions (Panthera leo) fitted with collar-mounted GPS units and tri-axial motion sensors recording at 1 and 40 Hz, respectively. The findings support the hypothesis and show that distance moved estimates were, on average, overestimated by greater than 80% prior to GPS screening. We present the conceptual and mathematical protocols for screening fix inaccuracy within high-resolution GPS datasets and demonstrate the importance that MVF has for avoiding inaccurate and biased estimates of movement.  相似文献   
3.
Reviews the book, Treating the juvenile offender edited by Robert D. Hoge, Nancy G. Guerra, and Paul Boxer (see record 2008-02979-000). This book rejuvenates interest in treatment for juvenile offenders, outlining the important advances that have been made, key challenges that remain, and useful principles for effectively meeting these challenges. Key themes that are emphasised include the importance of evidence-based approaches, interventions that are sensitive to the ecological systems within which youth are embedded, and rehabilitative strategies that are closely informed by research on youths’ risks, needs, and strengths. This book does not deliver a quick manual on how to deliver a particular program, but instead carefully models how to think about and approach treatment. While the book remains accessible to beginners, it is written in a manner which will be thought-provoking and informative even for experts. Furthermore, it is likely to have the positive effect of leaving readers with a desire to learn and do more to improve current practices. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
The feasibility of quantifying the perceived active ingredient (P57) in Hoodia gordonii raw material using Fourier transform near- and mid-infrared spectroscopy combined with chemometric techniques was investigated. The concentration of P57 (a triterpene glycoside) was determined in 146 plant samples with liquid chromatography coupled to mass spectrometry and these values were used to develop a calibration model based on the partial least squares projections to latent structures (PLS) and orthogonal projections to latent structures (O-PLS) regression algorithms. The performance of each calibration model was evaluated according to the root mean square error of prediction (RMSEP) and correlation coefficient (R2). The PLS model with 2nd derivative pre-processing predicted P57 content based on the FT-NIR spectra with the best accuracy and a correlation coefficient (R2) value of 0.9629 and the lowest RMSEP of 0.03%. These results demonstrated that FT-NIR spectroscopy can be used to rapidly quantify P57 in H. gordonii raw material with high accuracy.  相似文献   
5.
Canadian clinicians have used American norms for adult intelligence tests for more than 60 years. However, the availability of the Canadian norms for the WAIS-III prompts clinicians in Canada to make a decision regarding which norms to use in clinical practice. The purpose of this study is to compare the interpretive effects of applying American and Canadian normative systems in a sample of 100 forensic psychiatry and neuropsychiatry inpatients. The Canadian normative system yielded scores that were systematically lower than the American scores. Thus, clinicians may conclude greater impairment in intellectual ability when using Canadian norms. The index scores that were most similar were Processing Speed followed by Verbal Comprehension. With the exception of these two indices, clinically different conclusions might be derived on 13-21% of individual IQ or Index scores for these patients. The scores that differed the most were the Full Scale IQ and the Performance IQ. The subtests, in general, were highly similar across the normative systems, although scores using the Canadian norms were systematically lower. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
With the application of adjudicative competence requirements to adolescent defendants, there is a growing need for interventions to enhance the legal capacities of adolescents who are found to be incompetent. By reviewing developmental, clinical, and educational research, the authors discuss whether it is possible to enhance youths' legal capacities and, if so, what the most promising approaches may be. Psychoeducational interventions for youth are discussed, as well as the possibility of changing the demands of the juvenile justice system to try borderline-competent youth in juvenile court. The authors conclude that there is evidence to believe it may be challenging to enhance youths' legal capacities, particularly when youth have limited rational understanding and/or legal reasoning capacities, and when these deficits stem from developmental immaturity and/or mental retardation. A research agenda is proposed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
In laser welding technique, a real-time control of temperature distribution inside the irradiated materials is essential when attempting to optimize the process. For all laser welding methods that operate by the transmission principle, the difficulty of recording the developed temperature at the interface derives from the fact that materials to be welded are in contact throughout the entire process. In the present study, in order to overcome this issue, a contact-free method such the infrared thermography is used for surface temperature measurement. Corroborating this data with a numerical simulation of the temperature field evolution inside the components, an assessment of optimal process parameters is possible. The experimental investigations are made on amorphous polymers, in a typical configuration for through-transmission laser welding. The fine agreement obtained between the experimentally and calculated data, validate the infrared thermography as a non-destructive method for real-time monitoring of the welding process.  相似文献   
8.
The Gamsberg zinc deposit, located in the Northern Cape Province, represents South Africa’s greatest and most important unexploited base metal resource. Yet, in spite of its size, the low zinc grade combined with the high manganese content of the sphalerite continues to prohibit development of the deposit, as the high manganese content makes the zinc concentrates unsuitable for processing by conventional smelting methods, i.e. roasting, leaching/solvent extraction and/or electrowinning.Although numerous published investigations of the Gamsberg deposit have been undertaken, few have focused on the correlation between petrography and mineral chemistry of sphalerite and their implications on mineral processing. In accordance, the aims of this investigation are to highlight the importance of conducting a detailed geometallurgical investigation, as well as provide some new constraints on the metallurgical behavior of sphalerite and zinc concentrates from the Gamsberg deposit. Detailed analysis of sphalerite by petrographic and various microanalytical techniques reveal a marked absence of correlation between crystal morphology and mineral chemistry, necessitating a chemically based classification scheme. As such, six sphalerite populations where identified. They are: zinc-, cobalt-, iron- and manganese-rich, as well as manganese-enriched and manganese-poor. The zinc- and cobalt-rich populations display high zinc contents and low concentrations of iron and manganese, while the iron-rich population displays higher iron contents. Dominating the sphalerites of the mineralized pelitic schist is the manganese-enriched population. Of volumetrically lesser importance are the manganese-poor and -rich populations. The manganese-rich population contains high levels of iron, manganese, cobalt and cadmium relative to the zinc-rich population. In contrast, the manganese-poor population displays similar concentrations of cobalt and cadmium to the zinc-rich population, with iron and manganese intermediate between the zinc- and iron-rich populations.Comparisons between the sphalerite populations and milling size fractions reveal a consistent correlation between sphalerite mineral chemistry and size fractions with the coarser-grained concentrates being economically less favorable compared to the finer-grained concentrates, which display higher zinc contents. Combined with other lines of evidence, this suggests that the sphalerites of mineralized pelitic schist exhibit extensive solid solution that will have an effect on process optimization. For instance, it suggests that milling to a finer grain size will not remove or reduce the iron and manganese content. Another concern to processing will be the variable mineral chemistry of sphalerite, which might cause some sphalerites to display a delayed response during flotation or misreport to the lead concentrate. In spite of this, using solvent extraction, the elevated manganese content of the concentrates could be controlled, while simultaneously recovering zinc and manganese for sale. Hence, the recovery of manganese metal as a by-product could potentially enhance the economics of the deposit. Alternatively, other forms of mineral processing and metal extraction must be evaluated to meet the target grades and recoveries.  相似文献   
9.
Recently a theoretical analysis of PCR efficiency has been published by Booth et al. (2010). The PCR yield is the product of three efficiencies: (i) the annealing efficiency is the fraction of templates that form binary complexes with primers during annealing, (ii) the polymerase binding efficiency is the fraction of binary complexes that bind to polymerase to form ternary complexes and (iii) the elongation efficiency is the fraction of ternary complexes that extend fully. Yield is controlled by the smallest of the three efficiencies and control could shift from one type of efficiency to another over the course of a PCR experiment. Experiments have been designed that are specifically controlled by each one of the efficiencies and the results are consistent with the mathematical model. The experimental data has also been used to quantify six key parameters of the theoretical model. An important application of the fully characterized model is to calculate initial template concentration from real-time PCR data. Given the PCR protocol, the midpoint cycle number (where the template concentration is half that of the final concentration) can be theoretically determined and graphed for a variety of initial DNA concentrations. Real-time results can be used to calculate the midpoint cycle number and consequently the initial DNA concentration, using this graph. The application becomes particularly simple if a conservative PCR protocol is followed where only the annealing efficiency is controlling.  相似文献   
10.
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