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1.
To measure prefrontal and subcortical activity during a cognitive task, we examined 19 newly diagnosed schizophrenics and patients with schizophreniform psychosis. Seven healthy volunteers served as controls. The patients were drug naive or had received neuroleptics for a few days only. Cerebral blood flow distribution was depicted by single photon emission computed tomography at rest and during activation with the Wisconsin Card Sorting Test. A significant relative activation deficit in the left inferior-prefrontal region was revealed during the Wisconsin Card Sorting Test in the patient group. Furthermore, the patients had impaired striatal suppression on the left side during the cognitive task. The test performance was significantly impaired in the patients. The inability to reduce striatal activity may be due to a lack of corticostriatal feedback during prefrontal activation.  相似文献   
2.
Forty-eight consecutive applicants and 30 known clonidine-abusing methadone patients at three methadone treatment programs were surveyed regarding their use of clonidine. Two distinct patterns of clonidine use emerged. Of 22 applicants who took clonidine illicitly, 15 used it primarily to decrease opioid withdrawal, as well as for its sedating effect. Applicants mostly obtained it from physicians, used an average dose of 0.37 mg at a time, and about one third believed clonidine to be addictive. In contrast, clonidine-using patients took clonidine primarily for its psychoactive effects, including the interaction with methadone, in addition to decreasing opioid withdrawal. Patients obtained clonidine frequently on the street and from family or friends, but less from physicians. The average reported dose for patients was 0.6 mg. The vast majority of these patients felt clonidine was addictive. Our findings, when coupled with the risk inherent in clonidine overdose, suggest that further research into the identification and treatment of clonidine abuse among methadone patients is warranted.  相似文献   
3.
Fracture healing and callus formation have traditionally been evaluated by using X-ray radiography. Here we compared X-ray radiography and peripheral quantitative computed tomography (pQCT) in evaluating the healing callus of standardized tibial fractures in 141 female rats after a 4- or 8-week follow-up. The results were compared with the tensile (4-week) and compressive (8-week) failure load of the callus. The projectional size of callus, as defined from lateral ex vivo radiographs, correlated significantly with the pQCT-defined cross-sectional area (CSA) of mid-callus. This relationship was dependent on the pQCT attenuation threshold, being higher for the CSA of compact bone (r = 0.85, P < 0.0001) than for the total bone CSA (r = 0.68, P < 0.0001). Radiographically defined callus projectional area also correlated strongly with bone mineral content (BMC) (r = 0.84–0.86, P < 0.0001). The mean optical density of the callus analyzed from the radiographs had only a weak correlation with the pQCT-defined bone mineral density (BMD) of callus. A weak negative relationship was found between CSA and BMD. The optical density analyzed from lateral radiographs did not correlate with the tensile or compressive failure load of callus. Callus size, BMC, and BMD were associated with the compressive failure load, whereas both radiographs and pQCT were poor in explaining the failure load in tension. Received: 28 June 1999 / Accepted: 28 October 1999  相似文献   
4.
The type VI secretion system (T6SS) is the most prevalent bacterial secretion system and an important virulence mechanism utilized by Gram-negative bacteria, either to target eukaryotic cells or to combat other microbes. The components show much variability, but some appear essential for the function, and two homologues, denoted VipA and VipB in Vibrio cholerae, have been identified in all T6SSs described so far. Secretion is dependent on binding of an α-helical region of VipA to VipB, and in the absence of this binding, both components are degraded within minutes and secretion is ceased. The aim of the study was to investigate if this interaction could be blocked, and we hypothesized that such inhibition would lead to abrogation of T6S. A library of 9,600 small-molecule compounds was screened for their ability to block the binding of VipA-VipB in a bacterial two-hybrid system (B2H). After excluding compounds that showed cytotoxicity toward eukaryotic cells, that inhibited growth of Vibrio, or that inhibited an unrelated B2H interaction, 34 compounds were further investigated for effects on the T6SS-dependent secretion of hemolysin-coregulated protein (Hcp) or of phospholipase A1 activity. Two compounds, KS100 and KS200, showed intermediate or strong effects in both assays. Analogues were obtained, and compounds with potent inhibitory effects in the assays and desirable physicochemical properties as predicted by in silico analysis were identified. Since the compounds specifically target a virulence mechanism without affecting bacterial replication, they have the potential to mitigate the virulence with minimal risk for development of resistance.  相似文献   
5.
Various bone proteins and growth factors in specific concentrations are required for bone formation. If the body cannot produce sufficient quantities of these factors, bone trauma can be healed with an implant that includes the required factors in a carrier. This study was designed to evaluate various calcium salt candidates that can be used as carrier with reindeer bone protein extract to induce ectopic bone formation in the muscle pouch model of mouse. The bone protein extract was either impregnated into the disc form of carrier or mixed with carrier powder before implantation. The radiographic analysis indicated increased bone formation in all of the active groups containing the bone protein extract compared to the controls within 21 days follow-up. The highest bone formation was seen in the group with calcium sulfate with stearic acid where new bone and calcified cartilage were clearly visible. The greatest bone formation occurred in the groups that had bone protein extract readily available. This indicates that the bone forming factors in sufficient concentrations are required at the early stage of bone formation. The calcium sulfate with stearic acid was the most suitable and effective carrier for reindeer bone protein extract.  相似文献   
6.
Several quality of life instruments were considered for use in a Greek mental health environment. Subjective Quality of Life Profile was chosen as it was easy to complete and covered the issues raised by patients with schizophrenia through interviews. Confirmatory factor analysis gave credence to the four-dimensional structure identified by the original authors. Patients with schizophrenia were generally satisfied with their quality of life, found the items in the instrument important and were optimistic about expectations for change. Age, gender, education, marital status and years of sickness were not statistically significant in a general linear model with quality of life as the outcome for the 27 core questions. There were some statistically significant results for the three disease-specific questions; positive expectation was correlated positively with education and negatively with years of sickness.  相似文献   
7.
Mobile technology has been increasingly adopted in promotion of mental health among older people. This study assessed the feasibility of a mobile mental wellness training application for individual use and for group work from the perspectives of older adults and social care professionals. The older individuals recruited for the study were participants in a Circle of Friends group and family caregivers' peer support group offered by the communal senior services. The qualitative and quantitative results of interviews, questionnaires, observation, and application usage were reported. Seven older adults started using the application independently at home in parallel with the group activity. This study revealed new information regarding the barriers to the older adults' full adoption of such mobile technologies. The results indicated that there may be potential in the incorporation of mobile technologies in promotion of mental health of older people at group settings.  相似文献   
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This qualitative study investigated the experiences of mothers who have a child with communication difficulties resulting from cerebral palsy (CP). There is a dearth of information about parents' experiences of having a child with CP and communication difficulties. Three participants, whose children had moderate or severe CP and communication difficulties, were recruited from a voluntary organization. Participants were interviewed using an in-depth, semi-structured interview guide. Interviews were audio-recorded, then transcribed and subsequently analysed using Grounded Theory methods. Five main themes emerged, combining to form the core category of mothers dedicating their attention to their children . The information gleaned from this study could have important implications for nurses involved in facilitating communication, including speech and language therapists, occupational therapists and registered nurses. By becoming more aware of the experiences of parents with a child with CP and communication disorders, nurses may be better able to plan and implement therapy and also support communication aims. The study concludes with a discussion of further research avenues, suggesting that a study investigating the experiences of parents of children with other types of physical disabilities affecting communication should be conducted to determine the similarities and differences of parents of children with other kinds of disability. A similar study with a larger sample could be conducted to validate the findings of the current study.  相似文献   
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