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961.
Fifteen plant species were collected from the Nelspruit Botanical Garden based on a list of plants provided by Phytomedicine Programme at the University of Pretoria and their ethnopharmacological information. Hexane, dichloromethane (DCM), acetone and methanolic extracts were screened for antimycobacterial activity against Mycobacterium smegmatis. The acetone extract of Milletia stulhimannii was the most active, showing activity against Mycobacterium smegmatis with minimum inhibitory concentration (MIC) value of 0.13 mg/ml. Acetone extracts for all plants had lower MIC values ranging between 0.11–1.25 mg/ml against M. smegmatis. Milletia stulhimannii, Albizia gummifera, Xanthocercis zambesiaca and Barringtonia racemosa have shown great potential as anti-tuberculosis agents. They were active against M. smegmatis with average MIC values of acetone extracts of 0.13 mg/ml.  相似文献   
962.

Background

Contemporary learning technologies, such as massively multiplayer virtual worlds (MMVW), create new means for teaching and training. However, knowledge about the effectiveness of such training is incomplete, and there are no data regarding how students experience it. Cardiopulmonary resuscitation (CPR) is a field within medicine in high demand for new and effective training modalities.

Objective

In addition to finding a feasible way to implement CPR training, our aim was to investigate how a serious game setting in a virtual world using avatars would influence medical students’ subjective experiences as well as their retention of knowledge.

Methods

An MMVW was refined and used in a study to train 12 medical students in CPR in 3-person teams in a repeated fashion 6 months apart. An exit questionnaire solicited reflections over their experiences. As the subjects trained in 4 CPR scenarios, measurements of self-efficacy, concentration, and mental strain were made in addition to measuring knowledge. Engagement modes and coping strategies were also studied. Parametric and nonparametric statistical analyses were carried out according to distribution of the data.

Results

The majority of the subjects reported that they had enjoyed the training, had found it to be suitable, and had learned something new, although several asked for more difficult and complex scenarios as well as a richer virtual environment. The mean values for knowledge dropped during the 6 months from 8.0/10 to 6.25/10 (P = .002). Self-efficacy increased from before to after each of the two training sessions, from 5.9/7 to 6.5/7 (P = .01) after the first and from 6.0/7 to 6.7/7 (P = .03) after the second. The mean perceived concentration value increased from 54.2/100 to 66.6/100 (P = .006), and in general the mental strain was found to be low to moderate (mean = 2.6/10).

Conclusions

Using scenario-based virtual world team training with avatars to train medical students in multi-person CPR was feasible and showed promising results. Although we found no evidence of stimulated recall of CPR procedures in our test-retest study, the subjects were enthusiastic and reported increased concentration during the training. We also found that subjects’ self-efficacy had increased after the training. Despite the need for further studies, these findings imply several possible uses of MMVW technology for future emergency medical training.  相似文献   
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Individuals in clinical training programs concerned with critical medical care must learn to manage clinical cases effectively as a member of a team. However, practice on live patients is often unpredictable and frequently repetitive. The widely substituted alternative for real patients—high-fidelity, manikin-based simulators (human patient simulator)—are expensive and require trainees to be in the same place at the same time, whereas online computer-based simulations, or virtual worlds, allow simultaneous participation from different locations. Here we present three virtual world studies for team training and assessment in acute-care medicine: (1) training emergency department (ED) teams to manage individual trauma cases; (2) prehospital and in-hospital disaster preparedness training; (3) training ED and hospital staff to manage mass casualties after chemical, biological, radiological, nuclear, or explosive incidents. The research team created realistic virtual victims of trauma (6 cases), nerve toxin exposure (10 cases), and blast trauma (10 cases); the latter two groups were supported by rules-based, pathophysiologic models of asphyxia and hypovolemia. Evaluation of these virtual world simulation exercises shows that trainees find them to be adequately realistic to “suspend disbelief,” and they quickly learn to use Internet voice communication and user interface to navigate their online character/avatar to work effectively in a critical care team. Our findings demonstrate that these virtual ED environments fulfill their promise of providing repeated practice opportunities in dispersed locations with uncommon, life-threatening trauma cases in a safe, reproducible, flexible setting.  相似文献   
966.
OBJECTIVE: To determine whether boys meeting diagnostic criteria for juvenile mania and attention deficit hyperactivity disorder (mania-ADHD) may be distinguished from boys with ADHD alone on a range of clinical and family variables. METHODOLOGY: Boys aged 9-13 years with mania-ADHD (n = 25), ADHD alone (n = 99), or no psychiatric diagnosis (n = 27) were compared on parent and teacher report Child Behavior Checklists (CBCL) and Conners Questionnaires, self-report CBCLs, patterns of comorbidity, intellectual functioning, and family variables. RESULTS: Mania-ADHD subjects had significantly higher mean ratings than ADHD only subjects on the parent CBCL for the Withdrawn, Thought Problems, Delinquent Behavior and Aggressive Behavior scales and significantly higher rates of comorbid depression, anxiety and psychotic symptoms. Other variables did not distinguish the mania-ADHD and ADHD only groups. CONCLUSIONS: These data confirm previous research indicating that the CBCL may be used to assist in the clinical identification of manic children.  相似文献   
967.
Adult tissues contain highly proliferative, clonogenic cells that meet criteria of multipotent stem cells and are potential sources for autologous reparative and reconstructive medicine. We demonstrated that human dental pulp contains self renewing human dental pulp stem cells (hDPSCs) capable of differentiating into mesenchymal-derived odontoblasts, osteoblasts, adipocytes, and chondrocytes and striated muscle, and interestingly, also into non-mesenchymal melanocytes. Furthermore, we showed that hDPSC cultures include cells with the label-retaining and sphere-forming abilities, traits attributed to multipotent stem cells, and provide evidence that these may be multipotent neural crest stem cells.  相似文献   
968.
PURPOSE: To (1) obtain guidance on the preferred content and format of quick reference newborn blood spot screening information from the Minnesota Department of Health; (2) determine primary care physicians' perceptions of the benefits of genetic services; and (3) determine primary care physicians' satisfaction with genetic counseling services. METHODS: A written survey was mailed to family physicians and pediatricians in Minnesota (n = 300). RESULTS: Eighty physicians responded (28% response rate). Whereas 70% of respondents felt previous information received from the newborn screening program was adequate, 83% were interested in quick reference information. The majority of physicians preferred this information as a laminated sheet (63%). Physician procedure for an abnormal screen, newborn screening program protocol for an abnormal screen, and disease treatment and follow-up information were recommended for inclusion on quick reference. Over half of physicians agreed with the following benefits of genetic services: provide testing options (88%); evaluate family members (88%); reduce parental anxiety (87%); provide resources (83%); provide diagnostic information (76%); determine medical needs (67%); and determine emotional needs (51%). Ninety-nine percent of physicians were satisfied with genetic counseling services. CONCLUSIONS: Physicians indicated that reference material for primary care physicians should include a quick reference card with specific categories of information. Newborn screening programs should attempt to increase physician awareness of genetic services, including the subsequent medical and psychosocial benefits for their patients.  相似文献   
969.
Positive selection has long been thought to be a devise for producing a repertoire of T cells that can efficiently recognize foreign peptides in the context of self-major histocompatibility complex (MHC) molecules. However, in the light of recent evidence that long-term survival of mature T cells requires continuous contact with self-MHC molecules, the possibility for an additional role for positive selection has emerged: to generate a repertoire of T cells that can be maintained in the periphery through contact with self-MHC/peptide ligands. In support of this idea, our recent work suggests that positive selection is highly peptide specific and, more important, that mature T cells require extrathymic contact with the same MHC/peptide ligands that initially induced positive selection in the thymus in order for prolonged survival and to undergo homeostatic proliferation in response to T cell deficiency.  相似文献   
970.
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