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This study assessed the effects of a potentially distressing mailed survey on the emotional well-being and health care utilization (HCU) of 4,918 male and female veterans who applied for posttraumatic stress disorder disability benefits. Content analysis of spontaneous comments, in combination with analysis of subjects' HCU before and after receipt of the survey, suggested that spontaneously disclosed episodes of emotional upset were rare. In general, surveyed veterans' HCU decreased after receipt of the survey.  相似文献   
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BACKGROUND: Decision tools such as clinical decision support systems must be built on a solid foundation of nursing knowledge. However, current methods to determine the best evidence do not include a broad range of knowledge sources. As clinical decision support systems will be designed to assist nurses when making critical decisions, methods need to be devised to glean the best possible knowledge. AIMS: This paper presents a comprehensive knowledge development process to develop a nursing clinical decision support system. DISCUSSION: The Nurse Computer Decision Support Project (N-CODES) is developing a prototype for a prospective decision support system. The prototype is being constructed on rules and cases generated by the best available evidence. To accommodate the range of decisions made in practice, different types of evidence are necessary. The process incorporates procedures to uncover, evaluate, and assimilate information to develop the knowledge domain for a clinical decision support systems. Both formal and practice-based knowledge are included. The model contains several innovative approaches including the use of clinical experts and a network of practicing clinicians. CONCLUSION: These strategies will assist scientists and practitioners interested in determining the best evidence to support clinical decision support systems.  相似文献   
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An increased incidence of schizophrenia has been associated with several perinatal insults, most notably maternal infection during pregnancy and perinatal hypoxia. This study used a rat model to directly test if maternal exposure to bacterial endotoxin (lipopolysaccharide, LPS) during pregnancy alters behaviors relevant to schizophrenia, in offspring at adulthood. The study also tested if postnatal anoxia interacted with gestational LPS exposure to affect behavior. At adulthood, offspring from dams administered LPS on days 18 and 19 of pregnancy showed significantly increased amphetamine-induced locomotion, compared to offspring from saline-treated dams. A period of anoxia on postnatal day 7 had no effect on amphetamine-induced locomotion and there was no interaction between effects of gestational LPS and postnatal anoxia on this behavior. Offspring from LPS-treated dams also showed enhanced acoustic startle responses as adults, compared to offspring from saline-treated dams. In offspring tested for pre-pulse inhibition (PPI) of acoustic startle and for apomorphine modulation of PPI, no effects of either gestational LPS or of postnatal anoxia and no interactions between LPS and anoxia were observed. It is concluded that maternal LPS exposure during pregnancy in the rat may be a useful model to study mechanisms responsible for effects of maternal infection on behaviors relevant to schizophrenia, in offspring.  相似文献   
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In vitro metabolic studies revealed that along with UDP-glucuronosyltransferase (UGT) 1A1, the hepatic UGT1A9 and the extrahepatic UGT1A7 are involved in the biotransformation of the active and toxic metabolite of irinotecan, 7-ethyl-10-hydroxycamptothecin (SN-38). Variant UGT1A1 and UGT1A7 alleles have been reported but the polymorphic nature of the UGT1A9 gene has not been revealed yet. To further clarify the molecular determinants of irinotecan-induced toxicity, we have identified and characterized the functionality of novel UGT1A9 polymorphisms and determined whether additional missense polymorphisms exist in UGT1A7. Using direct DNA sequencing, four single nucleotide polymorphisms (SNPs) were identified in the first exons of UGT1A7 and UGT1A9. One of the two amino acid substitutions found in the UGT1A9 gene, UGT1A9*3 (M33T), results in a dramatic decrease in SN-38 glucuronide formation, with 3.8% of the activity of the UGT1A9*1 allele. In turn, the glucuronidation of flavopiridol, an anticancer drug biotransformed predominantly by UGT1A9, remains unaffected, indicating a substrate-dependent impact of this variant. UGT1A9*3 is detected only in Caucasians and 4.4% of the population tested was found heterozygous (*1/*3). Two additional UGT1A7 SNPs were found exclusively in African-American subjects and generate five alleles (UGT1A7*5 to *9) when combined to the four known SNPs present in UGT1A7*2, *3, and *4. Upon functional analysis with SN-38, five out of nine UGT1A7 allozymes exhibited much lower SN-38 glucuronidation activities compared with UGT1A7*1, all having in common the mutational changes at codons 115 or 208. Results suggest that these low SN-38 glucuronidating alleles may represent additional molecular determinants of irinotecan-induced toxicity and warrant further investigations.  相似文献   
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The authors investigated classical eyeblink conditioning in a relatively rare patient, B.R., with extensive cerebellar cortical atrophy and marked sparing of the dentate nucleus. Patient B.R.'s ability to acquire and extinguish simple associations (delay and trace conditioning tasks) as well as her ability to acquire more complex associations (temporal and simple discrimination tasks) were examined. There are 2 primary findings from this study. First, B.R. showed normal acquisition and extinction in delay and trace conditioning. Second, she demonstrated a complete inability to learn associative discriminations, even in the case of a simple 2-tone discrimination within the context of a delay paradigm. The latter finding was unexpected because of the sparing of her deep cerebellar nuclei. These data suggest that the cerebellar cortex, or pathways traversing cerebellar cortex, play an important role in classical eyeblink discrimination learning.  相似文献   
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