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81.
The authors evaluated mechanisms of change for a coping and communication-enhancing intervention (CCI) and supportive counseling (SC). They proposed that the effects of CCI on depressive symptoms would be mediated by psychological processes targeted by CCI, namely increases in the following: positive reappraisal, acceptance, planful problem solving, attempts to understand emotional reactions to cancer, emotional expression, seeking of emotional and instrumental support, and self-esteem. The authors hypothesized that the effects of SC on depressive symptoms would be mediated by the processes encouraged by SC, in this case increases in the following: expression of emotions, attempts to understand emotional reactions to cancer, and self-esteem. Three hundred fifty-three women were randomized to a CCI, SC, or usual care control group and completed measures at preintervention and 3, 6, and 9 months later. The effects of CCI were fully mediated by positive reappraisal, problem solving, and self-esteem and partially mediated by emotional expression. The effects of SC were partially mediated by positive reappraisal. These findings provide support for hypothesized mediators for CCI. The authors were less able to identify mediators for SC. Future research might benefit from identifying SC mediators. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Opioids have been regarded for millennia as among the most effective drugs for the treatment of pain. Their use in the management of acute severe pain and chronic pain related to advanced medical illness is considered the standard of care in most of the world. In contrast, the long-term administration of an opioid for the treatment of chronic noncancer pain continues to be controversial. Concerns related to effectiveness, safety, and abuse liability have evolved over decades, sometimes driving a more restrictive perspective and sometimes leading to a greater willingness to endorse this treatment. The past several decades in the United States have been characterized by attitudes that have shifted repeatedly in response to clinical and epidemiological observations, and events in the legal and regulatory communities. The interface between the legitimate medical use of opioids to provide analgesia and the phenomena associated with abuse and addiction continues to challenge the clinical community, leading to uncertainly about the appropriate role of these drugs in the treatment of pain. This narrative review briefly describes the neurobiology of opioids and then focuses on the complex issues at this interface between analgesia and abuse, including terminology, clinical challenges, and the potential for new agents, such as buprenorphine, to influence practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Some materials when exposed to various conditions can exhibit a rise in temperature without requiring an external heat source. Generally referred to as pyrophoric or self-heating substances, they challenge the safety of materials handling, storage and transportation. Reliably assessing the self-heating potential of materials is thus essential. Over the years several test protocols have been developed. A widely accepted method is that recommended by the United Nations (UN) to certify the safety of shipping pyrophoric goods. Our test work on sulphide materials has shown that the UN test can give false negatives if the sample oxidation history is not considered. Depending on the degree of oxidation (‘weathering’), the same sulphide material can exhibit self-heating ranging from safe to hazardous. To make the UN test, and other single-stage self-heating procedures, more reliable in assessing self-heating potential of sulphide materials, it is recommended that a weathering step be incorporated in the test protocol. Our test work on two sulphide samples, an ore and a concentrate, demonstrates the impact of incorporating a weathering stage in the test protocol.  相似文献   
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Bilateral superior ophthalmic vein (SOV) enlargement has rarely been shown to occur in patients with septic and aseptic cavernous sinus thrombosis, Graves' disease due to obstruction of the SOV by enlarged extraocular muscles, or carotid-cavernous fistulas caused by retrograde flow. The authors describe 11 patients with bilateral SOV enlargement associated with cerebral swelling as detected by computerized tomography scanning. The bilaterally enlarged SOVs returned to a normal size following resolution of cerebral swelling and elevated intracranial pressure. To the authors' knowledge, this is the first report of bilateral SOV enlargement associated with diffuse cerebral swelling that subsequently resolved after treatment of the cerebral edema. The authors believe that the bilateral SOV enlargement was caused by mechanical cavernous sinus venous stagnation due to cerebral swelling, a syndrome that occurs more commonly than currently appreciated.  相似文献   
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We have developed a radial basis function network (RBFN) for visual autonomous road following. Preliminary testing of the RBFN was done using a driving simulator, and the RBFN was then installed on an actual vehicle at Carnegie Mellon University for testing in an outdoor road-following application. In our first attempts, the RBFN had some success, but it experienced some significant problems such as jittery control and driving failure. Several improvements have been made to the original RBFN architecture to overcome these problems in simulation and more importantly in actual road following, and the improvements are described in this paper.  相似文献   
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