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991.
The authors report the case of a 33-year-old woman who exhibited, at the age of 17, a left-sided hemiplegia, which was followed by good motor recovery, though with a permanent deficit in fine finger movements. She had a widespread loss of neural tissue in the right hemisphere (crossed cerebrocerebellar atrophy), including (1) marked atrophy and thinning of the precentral and postcentral gyri; (2) widespread deep white matter destruction, including the corticospinal tract; and (3) crossed cerebellar atrophy. Except over the supplementary motor area (SMA), transcranial magnetic stimulation did not elicit motor evoked potentials in the affected hand. Nevertheless, during opening and closing of the affected hand, functional magnetic resonance imaging showed an activation of the lesioned primary sensorimotor cortex (SMC), as well as of the intact SMA and the parietal areas, but not of the ipsilateral motor areas. The authors speculate that recovery was achieved by a motor command generated in the SMC and the parietal cortex, passing through corticospinal axons originating in the SMA.  相似文献   
992.
Attenders (n = 124, response rate 84%) of five GPs in Montpellier completed questionnaires on health (reason for visit, cause of problem, GHQ-12), disability (WHODAS II) and service use (CSRI). For each patient, the GP filled in a brief form including a rating of severity of physical and psychological illness. Overall 30.6% of patients were classified as GHQ cases indicating probable non-psychotic psychiatric morbidity and 58.9% were rated as having a physical illness by the GP. Patients with psychiatric morbidity showed as high levels of disability as those with a physical illness, with however a greater number of domains of life affected. They also had a greatly increased number of disability days and used services to a greater extent than those without psychiatric morbidity, these links being stronger than with physical illness. Use of the WHODAS II and the CSRI has not been previously reported in France. This study shows that they could be useful instruments for depicting disability and service use in general practice. The findings from this initial study indicate the need for greater research in primary care focusing on accurate detection and treatment of patients so that disability and excess service use associated with psychiatric morbidity might be reduced.  相似文献   
993.
Identifying blood biomarkers may be of particular value in neurologic disorders such as stroke because of the difficulty in directly studying the brain and its blood vessels. Markers of brain injury, inflammation, excitotoxicity, and oxidative damage have been evaluated for their value in stroke diagnosis, treatment, and management, but none has proved to be sensitive or specific enough for routine clinical use. However, new cellular and molecular profiling approaches using the peripheral blood offer the potential for identifying panels of genes and proteins by increasing specificity while maintaining sensitivity. Furthermore, the first biomarker for predicting stroke risk associated with atherosclerosis (lipoprotein-associated phospholipase A2) was recently approved by the United States Food and Drug Administration. The ultimate aim for stroke biomarkers is to develop rapid, easy to use, widely available, and inexpensive diagnostic tests that can be used in the clinic and in clinical trials.  相似文献   
994.
995.
BACKGROUND: Asking psychiatric in-patients about their drug consumption is unlikely to yield reliable results, particularly where alcohol and illicit drug use is involved. The main aim of this study was to compare spontaneous self-reports of drug use in hospitalized psychiatric patients to biological measures of same. A secondary aim was to determine which personal factors were associated with the use of tobacco, alcohol, and illicit drugs as indicated by these biological measures. METHODS: The consumption of substances was investigated using biological measures (urine cotinine, cannabis, opiates, cocaine, amphetamines and barbiturates; blood carbohydrate-deficient transferrin [CDT] and gamma-glutamyl transferase [GGT]) in 486 consecutively admitted psychiatric patients, one day following their hospitalization. Patients' self-reports of alcohol, tobacco and illicit drugs consumption were recorded. Socio-professional and familial data were also recorded. RESULTS: The results show a low correlation between biological measures and self-reported consumption of alcohol and illicit drugs. Fifty-two percent of the patients under-reported their consumption of illicit drugs (kappa=.47). Patients with schizophrenia and personality disorders were more likely to disclose their illicit drug consumption relative to patients suffering from mood disorders and alcohol dependence. Fifty-six percent of patients underreported alcohol use, as evaluated by CDT (kappa=.2), and 37% underreported when using the CDT+GGT measure as an indicator. Smoking appeared to be reported adequately. In the study we observed a strong negative correlation between cannabis use and age, a strong correlation between tobacco and cannabis use, and correlations between tobacco, cannabis and alcohol consumption. CONCLUSION: This study is the first to compare self-reports and biological measures of alcohol, tobacco and illicit drug uses in a large sample of inpatients suffering from various categories of psychiatric illnesses, allowing for cross-diagnosis comparisons.  相似文献   
996.
An Historical Perspective from the Green Revolution to the Gene Revolution   总被引:2,自引:0,他引:2  
W Paul Davies  MSc  PhD 《Nutrition reviews》2003,61(S6):S124-134
Since the 1960s conventional crop breeding has increased food production commesurate with the growing population. For agricultural development to continue, the exploitation of greater genetic diversity and modern biotechnology are becoming increasingly important. This article reviews the milestones achieved by the Green Revolution and many of the recent breakthroughs of modern biotechnology.  相似文献   
997.
998.
PURPOSE: To examine the application of statistical parametric mapping (SPM) to analyze ictal single-photon emission computed tomography (SPECT) scans in surgical candidates with extratemporal lobe epilepsy. METHODS: The authors selected patients who underwent successful ictal SPECT acquisition in the process of surgical treatment of intractable partial epilepsy. Thirteen patients were identified who met inclusion criteria for confident seizure localization from either intracranial electroencephalogram recordings or epilepsy surgery outcome. In these cases, ictal scans were registered to an in-house-developed normal SPECT atlas composed of 14 spatially normalized brains of normal subjects. SPM96 was used to test on a voxel-by-voxel basis for statistically significant increases in blood flow associated with each patient's ictal scan. The results were then mapped back onto the patient's magnetic resonance image (MRI) for final interpretation. Statistical parametric mapping (SPM) analysis of ictal SPECT scans was compared to both conventional visual interpretation and the analysis of subtraction ictal SPECT co-registered to MRI (SISCOM). RESULTS: Ten of 13 patient scans showed localizing focal ictal increases in regional cerebral blood flow, all of which were concordant with ultimate epilepsy localization. Of the 3 cases not localized with SPM, 1 was localized by conventional visual interpretation and another, not localized by visual interpretation, was correctly localized with SISCOM. Two cases not localized by SISCOM were localized by both visual and SPM analysis. CONCLUSIONS: This work provides supportive evidence for proof of principle that SPM can be used to provide objective, accurate analysis of ictal SPECT scans in patients with extratemporal lobe epilepsy.  相似文献   
999.
This study looks at the psychogeriatric nurse's decision-making process and on this basis seeks to describe the implementation of psychogeriatric nursing in a mental hospital. The subjects consist of 26 nurses working on the psychogeriatric wards of one hospital. The data were collected using a questionnaire (n = 26), a 1-week time-usage analysis, content analysis of nursing plans (n = 56), and observation of planning meetings (n = 15). The results for different phases of the decision-making process suggested that nurses had little difficulty with the identification of problems. Data collection tended to concentrate on the physical side of nursing work. The setting of explicit targets for nursing care proved to be difficult. The vast majority of the nurses (85%) felt that decision-making on different nursing alternatives was only moderately or not at all successful. Over half of the nurses felt that their ability to evaluate the outcome of treatment and nursing was either satisfactory or poor. Time-usage analysis indicated that the nurses had frequent interaction with their patients in connection with basic care, although the nurses themselves did not regard this part of their work as active interaction with the patient.  相似文献   
1000.
The interactive use of magnetic resonance imaging (MRI) techniques is increasing in operating theaters. A study was performed on 17 male company volunteers to assess the neurobehavioral effects of exposure to magnetic fields from a 1.5 Tesla MRI system. The subjects' neurobehavioral performances on a neurobehavioral test battery were compared in four 1-hr sessions with and without exposure to magnetic fields, and with and without additional movements. Adverse effects were found for hand coordination (-4%, P < 0.05; Pursuit Aiming II) and near visual contrast sensitivity (-16% and -15%, P < 0.10; Vistech 6000). The results from the remaining tests were inconclusive due to a strong learning effect. No additional effect from gradient fields was detected. The results indicate that working near a 1.5 Tesla MRI system may lead to neurobehavioral effects. Further research is recommended, especially in members of operating teams using interactive MRI systems.  相似文献   
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