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81.
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The absolute right to refuse medical treatment, even if the reasons are irrational, is confined to competent adults. Children under 16 years can give legal consent to treatment in the absence of consent from those with parental responsibility. Children under 18 years do not, however, have an absolute right to consent, or refuse to consent, to treatment. The views of children assume increasing importance with age and maturity. Accident and emergency medical and nursing staff may face difficult decisions when children, or those with parental responsibility, refuse to consent to medical treatment. This paper presents guidelines designed to guide the decision making process in immediately or potentially life threatening conditions and in non-life-threatening conditions.  相似文献   
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Presents a model for conceptualizing 4 basic types of suicidality among substance abusers (avoidance of painful consequences, the depressive experience of "crashing," the threat of personal loss, and environmental strain) and offers practical tips for treating the problem. Four general forms of intervention are discussed: pacing the crisis encounter; desensitizing the patient's sense of desperation; talking frankly about the suicidality; and attending to one's own needs as a counselor. These crisis-intervention tips are intended to aid counselors in handling suicidality as it is manifested in substance-abusing populations. Tips and guidelines for suicidal risk assessment with drug and alcohol abusers are given. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Given a capable human being and a computer, it is possible to make an approximation to the solution of a nonlinear differential equation. However, under the (usually correct) assumption that the equation is analytically intractable, the result of the computation is not the exact solution; indeed it may be so far from the exact solution as to be completely useless. We are interested in the relationship between the effort expended by the human and the computer, and the duality of the computed approximation to a partial or ordinary differential equation. To be specific, we would like to think in terms of a cost-benefit analysis. The cost of the computation is a combination of the human effort and computer resources used to obtain the approximation. The benefit includes, of course, the computed approximation, but it also includes an estimate of the quality of the approximation, that is, an error estimate. It is our opinion that in computational science, as with the experimental sciences, results should always be presented with some estimate of their accuracy. In addition, however, there is another facet to error estimation: one cannot even attempt a cost-benefit analysis or efficiency comparison of methods without an error estimate to evaluate the results  相似文献   
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Infection by human immunodeficiency virus type 1 (HIV-1) is often complicated by a variety of neurological abnormalities. The most common clinical syndrome, termed acquired immunodeficiency syndrome (AIDS) dementia complex, presents as a subcortical dementia with cognitive, motor, and behavioral disturbances and is unique to HIV-1 infection. The pathogenesis of this syndrome is poorly understood but is believed to involve interactions among virally infected macrophages/microglia, astrocytes, and neurons. In this study, we show that exposure of primary rat and human astrocytes to heat-activated HIV-1 virions, or to eukaryotically expressed HIV-1 and HIV-2 envelope glycoproteins (gp120) stimulates amiloride-sensitive Na+/H+ antiport, potassium conductance, and glutamate efflux. These effects are blocked specifically by amiloride, an inhibitor of Na+/H+ antiport and by the selective removal of gp120 with immobilized monoclonal antibody. As a result of modulation of astrocytic function by gp120, the ensuing neuronal depolarization and glutamate exposure could activate both voltage-gated and N-methyl-D-aspartate-regulated Ca2+ channels, leading to increases in intraneuronal Ca2+ and neuronal death. These findings implicate the astrocyte directly in the pathogenesis of AIDS dementia complex.  相似文献   
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Complex rehabilitation of 20 patients with congenital and acquired maxillofacial deformations included psychological examinations using the finish-the-sentence test, Taylor's, Eysenck's [correction of Isenk's], Leonhard-Smisek, and Dembo-Rubinstein tests. Depressive states were detected in 4, neurotic reactions with depressive incorporations in 16 examinees. After surgery the manifestations of depression decreased in 60% of patients. Psychological studies helped improve the efficacy of surgery due to a favorable impact on the personality.  相似文献   
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Catalyst instabilities during the liquid phase partial oxidation of methane   总被引:2,自引:0,他引:2  
A promising catalytic system for the low temperature oxidation of methane to a methanol derivative has been investigated under both batch and semi-continuous operation in two different reactor types. The system comprises of a bimetallic palladium and copper(II) chloride catalyst contained in a trifluoroacetic acid (TFA) and an aqueous phase. Methane, oxygen and a co-reductant carbon monoxide constitute the gas phase. Typical operating conditions were a temperature of 85 °C and a pressure of 83 bar.

The yields of the methyl trifluoroacetate product observed in this present work were less than those obtained in other batch autoclave works, which employed only 4 ml of liquid phase, compared with 50 ml in this study. Furthermore, an encouraging initial product formation rate of ca. 40 mol/m3 h, quickly decreased after the first hour, and came to an apparent end after only 2 h. This observation had not been reported previously.

Work performed in a semi-continuous porous tube reactor (300 ml of re-circulating liquid phase) also showed the same reaction characteristics as in the batch reactor. Thus, the deteriorating product formation rate cannot be attributed to gaseous reactant depletion (batch operation). The results suggest problems associated with catalyst instabilities, e.g. with the previously elucidated Wacker chemistry.  相似文献   

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