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71.
ABSTRACT: BACKGROUND: The application of new technologies to the education of health professionals is both a challenge and a necessity. Virtual worlds are increasingly being explored as a support for education. Aim: The aim of this work is to study the suitability of Second Life (SL) as an educational tool for primary healthcare professionals. METHODS: Design: Qualitative study of accredited clinical sessions in SL included in a continuing professional development (CPD) programme for primary healthcare professionals. Location: Zaragoza I Zone Family and Community Medicine Education Unit (EU) and 9 health centres operated by the Aragonese Health Service, Aragon, Spain. METHOD: The EU held two training workshops in SL for 16 healthcare professionals from 9 health centres by means of two workshops, and requested them to facilitate clinical sessions in SL. Attendance was open to all personnel from the EU and the 9 health centres. After a trail period of clinical sessions held at 5 health centres between May and November 2010, the CPD-accredited clinical sessions were held at 9 health centres between February and April 2011. Participants: 76 healthcare professionals attended the CPD-accredited clinical sessions in SL. Main measurements: Questionnaire on completion of the clinical sessions. RESULTS: Response rate: 42-100%. Questionnaire completed by each health centre on completion of the CPD-accredited clinical sessions: Access to SL: 2 centres were unable to gain access. Sound problems: 0% (0/9). Image problems: 0% (0/9). Voice/text chat: used in 100% (10/9); 0 incidents. Questionnaire completed by participants in the CPD-accredited clinical sessions: Preference for SL as a tool: 100% (76/76). Strengths of this method: 74% (56/76) considered it eliminated the need to travel; 68% (52/76) believed it made more effective use of educational resources; and 47% (36/76) considered it improved accessibility. Weaknesses: 91% (69/76) experienced technical problems, while; 9% (7/76) thought it was impersonal and with little interaction. 65.79% (50/76) believed it was better than other distance learning methods and 38.16% (29/76) believed it was better than face-to-face learning. CONCLUSIONS: SL is a tool that allows educational activities to be designed that involve a number of health centres in different geographical locations, consequently eliminating the need to travel and making more effective use of educational resources.  相似文献   
72.
73.
While providing osteopathic manipulative treatment to patients with Parkinson's disease at the clinic of the New York College of Osteopathic Medicine of New York Institute of Technology, physicians noted that these patients may exhibit particular cranial findings as a result of the disease. The purpose of this study was to compare the recorded observations of cranial strain patterns of patients with Parkinson's disease for the detection of common cranial findings. Records of cranial strain patterns from physician-recorded observations of 30 patients with idiopathic Parkinson's disease and 20 age-matched normal controls were compiled. This information was used to determine whether different physicians observed particular strain patterns in greater frequency between Parkinson's patients and controls. Patients with Parkinson's disease had a significantly higher frequency of bilateral occipitoatlantal compression (87% vs. 50%; P < .02) and bilateral occipitomastoid compression (40% vs. 10%; P < .05) compared with normal controls. Over subsequent visits and treatments, the frequency of both strain patterns were reduced significantly (occipitoatlantal compression, P < .01; occipitomastoid compression, P < .05) to levels found in the control group.  相似文献   
74.
The oxidative stress in placental tissues during late pregnancy, as well as the relationship between reactive oxygen species (ROS) and the arachidonic acid (AA) pathway was evaluated in a neonatal streptozotocin (STZ)-induced diabetic rat model. Lipoperoxide levels are increased in diabetic tissues compared with control tissues (P<0.001) and they seem to increase throughout the development of gestation both in control (P<0.05) and STZ-induced diabetic (P<0.001) rats. Superoxide dismutase (SOD) activity is not modified on different days of pregnancy, but enzymatic activity is lower in diabetic tissues than in control tissues (P<0.01). Labour is preceded by an increase in placental 14C-prostaglandin conversion from 14C-AA in control and diabetic animals (P<0.05) and the thromboxane B2 (TXB2)/6-keto-prostaglandin F1alpha (PGF1alpha) ratio is higher in diabetic placental tissues than in controls. The addition of SOD and glutathione to the incubation medium does not modify prostanoid levels in control rats, but does decrease the AA conversion to PGF2alpha, PGE2 and TXB2 (P<0.05) in diabetic placenta. Superoxide radical generation (hypoxanthine/xanthine oxidase or hydrogen peroxide added to the incubation medium) produces a decrease in 6-keto-PGF1alpha (P<0.05) in control and diabetic tissues, whereas PGF2alpha, PGE2 and TXB2 levels, and PGF2alpha and TXB2 production are increased in control and diabetic animals respectively (P<0.05). Diabetic pregnant rats supplemented with a diet containing 400 mg day(-1) of alpha-tocopherol (vitamin E) have diminished placental PGF2alpha and TXB2 production and lipoperoxide levels. The results show a higher TXB2 and a decreased 6-keto-PGF1alpha placental production that may be linked to increased oxidative stress and to a reduced antioxidant capacity in STZ-induced diabetic rats. These imbalances, probably involved in abnormal placental structure and function, may potentially be corrected with dietary supplementation of alpha-tocopherol in diabetic pregnancies.  相似文献   
75.
Denervation-activated inward rectifier in frog slow skeletal muscle fibers   总被引:1,自引:0,他引:1  
We tested whether the absence of an inward rectifier channel in slow skeletal muscle fibers of the frog is regulated by innervation. Normal and denervated slow fibers were identified according to their passive electrical properties. In current-clamp experiments, anomalous rectification was quantified as the ratio of effective resistances for hyperpolarizing and depolarizing pulses. In isotonic potassium solution, this ratio was 0.45 +/- 0.1 (n = 14) for twitch fibers, whereas slow fibers displayed linear behavior [ratio = 1.0 +/- 0.05 (n = 15)]. However, denervated slow fibers showed anomalous rectification (ratio, 0.48 +/- 0.07; n = 5). This finding was supported by voltage-clamp experiments in which denervated slow fibers displayed (1) an inward rectifier current during hyperpolarizing pulses, (2) an increase in this current when [K(+)](o) was increased, and (3) a current inhibition after application of Ba(2+). These results suggest that frog slow fibers, which normally do not possess inward rectifier channels, can express them after denervation.  相似文献   
76.
The influence of direct electric stimulation on nerve regeneration was studied in a model of crush injury of the sciatic nerve of rats. Forty-three rats were used and distributed in four groups according to the procedure: (1) intact nerve, inactive circuit; (2) crush injury, inactive circuit; (3) intact nerve, active circuit; (4) crush injury, active circuit. The low intensity continuous current circuit (1 microA) was implanted in the lumbar region, the anode being fixed to the muscles proximally and the cathode below the nerve distally to the lesion site. The Sciatic Functional Index (SFI) was evaluated at weekly intervals for 3 weeks, the sciatic nerve being resected on the 21st day for histologic and morphometric studies. The SFI progressively improved and the average fiber nerve density recovered to a nearly normal value in Group 2 and increased in Group 4 compared with the control groups (1 and 3), but this was accompanied by a decreased average fiber nerve diameter. Both number and diameter of inter and intra-fascicular blood vessels increased in the stimulated nerves. We conclude that low intensity direct electric stimulation enhances nerve regeneration following a controlled nerve crush injury and increases blood supply by increasing number and diameter of vasa nervorum.  相似文献   
77.
This study was designed to evaluate early post partum rapid HIV testing of infants as surrogates for their mothers. In a screening of 971 infants whose mother's HIV-1 status was not known at delivery, 22 (= 2.26%) were found positive for antibodies by ELISA. Five were new cases and two (40%) were from transmitting mothers. This is in contrast with the UPR Women and Infants Transmission Study (UPR WITS) in which of 186 HIV-1 infected mothers none were transmitters. These were selected among thousands screened for anti-HIV-1 antibodies over a period of almost 5 years studied (September, 1996 through August, 2001). These results clearly indicate that all mothers at delivery should have a rapid test to determine their HIV-1 status to allow in the positive cases rapid intervention strategies to prevent perinatal transmission.  相似文献   
78.
OBJECTIVE: To evaluate the incidence and the prevalence of neutralising antibodies (NABs) to three interferon beta (IFNbeta) products in patients with multiple sclerosis (MS). METHODS: Sera were tested from 125 patients with relapsing-remitting MS. Patients were treated with IFNbeta-1b (Betaferon, n = 29) 8 MIU subcutaneously every other day, IFNbeta-1a (Avonex, n = 44) 30 microg intramuscularly once weekly, or IFNbeta-1a (Rebif, n = 36) 22 microg subcutaneously three times weekly for 6 to 18 months. An additional 16 patients were treated with Rebif 22 microg intramuscularly once or twice weekly. NABs were assessed using the cytopathic effect assay before treatment and every three months during treatment. Patients with two or more consecutive positive samples were considered to be persistent NAB positive (NAB+). RESULTS: At baseline, no patients were NAB+. NABs developed during the first three months of treatment and continued to develop until month 18. Over 18 months of treatment, the risk of being persistent NAB+ was 31% for Betaferon, 15% for Rebif, and 2% for Avonex (Betaferon versus Avonex, p = 0.001; Betaferon versus Rebif, p = 0.19; Rebif versus Avonex, p = 0.04). In all patients with one or more NAB+ samples, the risk of becoming NAB+ was 38% for Betaferon, 18% for Rebif, and 7% for Avonex (Betaferon versus Avonex, p = 0.0007; Betaferon versus Rebif, p = 0.10; Rebif versus Avonex, p = 0.07). At month 18, the prevalence of persistent NAB+ patients was 31.6% for Betaferon, 18.7% for Rebif, and 4% for Avonex. Numbers of NAB+ patients observed were similar with intramuscular Rebif and with subcutaneous Rebif. CONCLUSION: The three IFNbeta preparations have different degrees of immunogenicity, with Betaferon producing the highest incidence of NABs and Avonex the lowest. These differences should be considered by neurologists when selecting treatment for their patients with MS because NABs can reduce both bioavailability and clinical efficacy of IFNbeta.  相似文献   
79.
We present an usual case of intracranial dural arteriovenous fistula with perimedullary and spinal cord venous plexus drainage and discuss its etiological, physiopathological, diagnostic and therapeutic aspects.  相似文献   
80.
We carried out an ecological study in the most archaic area of Sardinia to obtain a reliable estimate of the prevalence of multiple sclerosis (MS) and to investigate the geographical variation in the prevalence across the 100 administrative communes. To estimate the area-specific prevalence rate, we adopted a Bayesian approach that makes it possible to filter out the random variation from the estimates and to obtain a map that reflects the true geographical variation in MS prevalence. 428 resident cases were identified by the case register, including 69 multiplex families. The overall prevalence was 157 per 100,000 inhabitants. The Bayesian area-specific prevalence ranged from 143 to 262/100,000. The high prevalence and its moderate geographical variation in a genetically homogeneous population, as well as the high number of multiplex families observed in the communes with the highest prevalence, could be interpreted as representing a high susceptibility of the population to MS.  相似文献   
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