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81.
Ram  Grol  Rethans  Schouten  Vleuten  & Kester 《Medical education》1999,33(6):447-454
OBJECTIVES: To develop a video assessment method for General Practitioners (GPs) by analysing issues of validity, reliability and feasibility of observation of videotaped regular consultations. DESIGN: In a cross-sectional study consultations of 93 GPs were video recorded in the practice during 1 week. The GPs registered consultation and patient data in a logbook; 16 consultations per GP were selected using preset criteria. The quality of communicative and medical performance of these consultations was assessed by GP observers with a validated instrument. The validity of the procedure was evaluated by checking the content of each GP's sample using specific sample criteria. Selection bias was estimated by multiple regression analysis, with sample characteristics as independent variables and scores on communication and medical performance as dependent variables. The influence of observation on GPs and patients was assessed by a questionnaire. Generalizability theory was used to estimate reliability. Feasibility was assessed by conducting a questionnaire, by keeping accounts, and by checking the technical quality of the videotaped consultations. SETTING: Universities of Nijmegen and Maastricht, The Netherlands. SUBJECTS: General Practitioners (GPs). RESULTS: The domain of general practice was well covered in the samples; content validity was satisfactory. With regard to the sample characteristics, only the total duration of consultations appeared to correlate significantly with both the score on communication and the score on medical performance. A majority (71%) of GPs reported not being influenced by the observation, except in the first cases, and recognizing their usual daily performance in the videotaped consultations. An acceptable level of reliability was reached after 2.5 hours of observation, i.e. 12 cases by a single observer. The method was well accepted by both GPs and patients. The costs were pound250 per GP. CONCLUSIONS: Video assessment of GPs in daily practice according to the procedures described is a valid and reliable method, one which is useful for education and quality improvement. There is a trade-off between feasibility on one hand and validity, reliability and credibility on the other hand. Compared to investments in observation methods in standardized settings, the costs of video observation of GPs' actual performance are acceptable.  相似文献   
82.
P3 component of the endogenous cerebral evoked response is a sophisticated, objective and quantitative approach to assess higher functions of the brain. This test was employed using auditory 'odd ball' paradigm to assess cognitive functions in thirty non insulin dependent diabetic patients (NIDDM) aged 43.6 +/- 9 yrs with poor blood glucose control. (HbAlc. 9.9 +/- 1.0%). The peak latencies of N2, P3 components of event related evoked potentials obtained in these patients were compared with 30 age and sex matched non diabetic healthy controls. Latencies of these potentials were: N2 = 248.0 +/- 36.3, P3 = 391.6 +/- 49.9 msec in NIDDM as compared to 220.6 +/- 26.4, 326.2 +/- 26.8 msec in controls and were highly significant (P < 0.001). The duration of disease, blood glucose level or the physical parameters of height, weight and blood pressure did not show any correlation with N2 or P3 latencies or amplitude. These findings provide an electrophysiological evidence of delayed cognition in poorly controlled NIDDM cases.  相似文献   
83.
The vasodilator effect of eriodictyol (5,7,3',4'-tetrahydroxyflavanone), isolated previously from the medicinal plant Satureja obovata Lag., was studied in rat thoracic aorta rings. Eriodictyol relaxed in a concentration-dependent manner the noradrenaline (10(-6) M) and KCl (80 mM) induced contractions. The relaxant effect was more potent in noradrenaline precontracted preparations (IC50 = 6.11 +/- 0.2 x 10(-5) M) than in those precontracted with KCl (IC50 = 2.96 +/- 0.1 x 10(-4) M). Eriodictyol produced weakly concentration-dependent inhibition of the phasic component induced by KCl and noradrenaline while the inhibition of the tonic phase of these contractions was more pronounced. These effects were endothelium independent. In addition, eriodictyol (10(-5) and 5 x 10(-5) M) inhibited CaCl2 cumulative concentration response curves. Eriodictyol weakly inhibited the release of calcium from the sarcoplasmic reticulum and its contribution to the relaxant effect seems to be slight. We have also observed the relaxant effect of eriodictyol on phorbol-12-myristate-13-acetate (PMA) (10(-7) M) induced contractions both in normal calcium (IC50 = 4.69 +/- 0.3 x 10(-5) M) and calcium-free medium (IC50 = 3.74 +/- 0.4 x 10(-5) M). Finally we studied the effects on protein kinase C (PKC) activity. This flavonoid did not show any activity. These results suggest that the vasodilator effect of eriodictyol in rat thoracic aorta could be partially related to the inhibition of calcium influx or other enzymatic protein subsequent to activation of PKC related to the activation of contractile proteins like myosin light chain kinase (MLCK).  相似文献   
84.
OBJECTIVE: The study reports the process of translation into Spanish and adaptation to the Hispanic culture of the Alcohol Use Disorder and Associated Disabilities Schedule (AUDADIS). This instrument is a structured diagnostic interview schedule specifically developed for the assessment of substance-related disorders and their comorbid disorders and disabilities. METHOD: A random sample (N = 169) of adults from a primary health care clinic in Puerto Rico was selected. The test-retest reliability of the instrument was examined across time and across interviewers, and the validity was assessed by comparing computer-derived diagnoses obtained through the administration of lay interviewers with best estimate diagnoses given by board-certified psychiatrists. RESULTS: For most diagnoses and symptoms studied, as well as for most of the alcohol consumption measures, the test-retest reliability of the Spanish AUDADIS was consistent with results reported in other national and international studies using this instrument. Good to excellent test-retest reliability was obtained for the diagnoses of alcohol dependence and major depression. Similarly, good to excellent agreement was obtained between the lay administered AUDADIS and best estimate diagnoses for most diagnostic categories, with the exception of dysthymia. As in other studies, the reliability and validity of the substance abuse category was poor. When agreement for this category was estimated independent of lifetime dependence, both the reliability and validity coefficients were considerably improved. CONCLUSIONS: The Spanish AUDADIS generally demonstrates good to excellent levels of reliability and validity that are comparable to findings reported for this instrument in other national and international studies.  相似文献   
85.
Both filtering surgery with Mitomycin-C and diode laser cyclophotocoagulation have proved to be effective alternatives in cases of glaucoma with poor surgical prognosis. The right eyes of 40 pigmented rabbits were randomly divided into 2 groups: Mitomycin-C group underwent filtering surgery with application of 0.4 mg/ml of Mitomycin-C whereas the diode laser (DL) group received 15 applications of 1.8 J (1800 mW. 1000 ms) distributed in 270°. Mean IOP showed statistical differences in two periods between days 3–13 and 45–60 — Mann-Whitney U test — with a higher IOP lowering in the DL group. The comparison of IOP survival curves (Log-Rank test) was not significant p = 0.070809. Ocular hypertension, hyphema and inflammatory signs were higher in the DL group, both in short and long term, but in terms of statistical significance only ocular hypertension showed differences p = 0.00011717 - Fisher exact test. Microscopic examination revealed patent sclerostomies in 60% of the MMC group eyes with different grades of fibroblastic proliferation. In the DL group we observed necrosis of the sclieral stroma and of the pigmented and unpigmented ciliary epithelium, with signs of thermal coagulation of the ciliary stroma and of the stromal vasculature. We must point out that the treatment with laser has proved to be more effective although both treatments showed very acceptable IOP lowering until 2 months after the surgery.  相似文献   
86.
The subcutaneous pedicled V-Y advancement flap (also known as the kite flap of Dufourmentel) has been described by many authors. Its versatility in reconstructive surgery is well known, both in facial reconstructive surgery as well as surgery of the trunk and extremities. Its advantages in achieving aesthetic reconstruction in specific facial regions have been less well emphasized in the literature. The flap can be designed within natural facial creases and heals inconspicuously because of its widely based subcutaneous or muscle pedicle which incorporates venous and lymphatic drainage over most of its length. The undesirable biscuiting or flap edema frequently observed with other conventional transposition flaps is avoided. We have found the V-Y flap particularly useful in reconstructing the lower eyelid/medial canthus, supra-alar, and nasolabial regions. Our experience with over 40 such flaps is described, and technical considerations in designing and elevating the flap are discussed.  相似文献   
87.
We compare the degree of nitrous oxide diffusion in three types of endotracheal tubes available in the market, by means of continuous monitoring of the pressure attained at the pneumoballoon. Among the systems designed to impede or to minimize nitrous oxide diffusion, we have used in this study the so called "rediffusion system". When the endotracheal tube possesses this system, the pressure attained at the pneumoballoon remained constant throughout the study period (23.2 +/- 0.53 mmHg at time zero vs 24.2 +/- 0.66 mmHg 50 min after administration of protoxide). In contrast, endotracheal tubes without "rediffusion system" showed a statistically significant increase (p less than 0.05) of pneumoballoon pressure (25.2 +/- 2.43 mmHg and 26.7 +/- 1.01 mmHg at time zero vs 45.2 +/- 3.12 and 44.3 +/- 2.41 mmHg 50 min after protoxide administration in the two other types of endotracheal tubes). We believe that during anesthesia with nitrous oxide the pneumoballoon pressure should be monitored or systems that avoid diffusion of this inhalational agent should be inserted. Our results indicate that endotracheal tubes equiped with "rediffusion system" are effective in impeding diffusion of the inhalational agents.  相似文献   
88.
Spatial and Temporal Patterns of Neurogenesis in the Chick Retina   总被引:9,自引:0,他引:9  
Chick embryo retinas were labelled in ovo by single injections of [3H]thymidine at selected times between days 2 and 12 of incubation. Embryos were later removed, at different stages of development, and the retinas processed for autoradiography of either serial sections or dissociated cell preparations. Analysis of unlabelled cells shows that neurogenesis starts, on day 2 of incubation, in a dorsotemporal area of the central retina, close to the posterior pole and to the optic nerve head. A gradient of neurogenesis spreads from this central area to the periphery, where neurogenesis ends, shortly after day 12, when the last few bipolar cells withdraw from the cell cycle. Additional dorsal-to-ventral and temporal-to-nasal gradients can be discerned in our autoradiographs. In all retinal sectors, ganglion cells start first to withdraw from the cell cycle, followed, with substantial overlapping, by amacrine, horizontal, photoreceptor plus Müller, and bipolar neuroblasts. Ganglion cells are also the first to reach the 50% level of unlabelled cells, followed this time by horizontal, photoreceptor, amacrine, Müller and bipolar cells. Finally, 100% levels of unlabelled cell populations are attained simultaneously by ganglion, horizontal and photoreceptor cells, followed by amacrine, then by Müller, and last by bipolar cells. Although all classes of neurons, in varying proportions, are being produced most of the time, our results also demonstrate that, in any given retinal area, the first cells leaving the cycle are determined to become ganglion cells, and the last ones bipolar cells, and not other types.  相似文献   
89.
The effects of Nd-YAG laser irradiation on platelet function in vitro were studied using platelet rich plasma obtained from the blood of healthy volunteers. Laser delivery was effected via the bare optical fibre, thermal hot tip fibre and spectraprobe and the effects of these probes on platelet function were compared. Fall in platelet count and mean platelet volume (MPV) were proportional to increasing energy delivery with all three probes, the effect being maximal with the spectraprobe, moderate with the hot tip and least with the bare optical fibre. A significant decrease in percentage aggregation of platelets in response to added ADP, collagen and ristocetin with increasing energy delivery was also observed with all three probes. The formation of preformed aggregates, however, showed an increase proportional to energy delivery with all three probes.The differential effects of the various probes used in this study on platelet function may enhance our understanding of the complex role played by platelets in the pathogenesis of complications such as arterial thrombosis and re-occlusion after laser angioplasty.  相似文献   
90.
H K Mangat 《Andrologia》1979,11(6):449-452
The effect of 10 days i.m. treatment of testosterone propionate (TP) on plasma testosterone and accessory reproductive organs were studied in adult (6 to 6 1/2 kg) male rhesus monkeys, housed under natural light conditions using six different dose levels. The study was scheduled in the month of September and October. To maintain the weight of accessory reproductive organs and testosterone levels in castrates, different dose levels of exogenous testosterone propionate were required: 3.2 mg/d for seminal vesicles, 4.8 mg/d for ventral prostate and 3.2 mg/d for plasma testosterone titer. The levels of so-called "physiological" doses of exogenous testosterone varied for various target organs under consideration. TP at a dose of 0.4 mg/d had a depressing effect on plasma testosterone in intact monkeys. For higher doses, plasma testosterone increased roughly similarly in both intact and castrated monkeys. It suggests that with otherwise "physiological" doses of testosterone propionate, there is an almost complete blockage of endogenous testosterone secretion.  相似文献   
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