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1.
Vestibular function laboratories utilize a multitude of diagnostic instruments to evaluate a dizzy patient. Caloric irrigators, oculomotor stimuli, and rotational chairs produce a stimulus whose accuracy is required for the patient response to be accurate. Careful attention to everything from cleanliness of equipment to threshold adjustments determine on a daily basis if patient data are going to be correct and useful. Instrumentation specifications that change with time such as speed and temperature must periodically be checked using calibrated instruments.  相似文献   
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Abstract: Background: The identification of an autoimmune mechanism for many patients with chronic idiopathic urticaria (CIU) was used as a rational for a controlled clinical trial of cyclosporine for adults with CIU not responsive to usual measures. That randomized placebo controlled clinical trial demonstrated clinical efficacy, acceptable safety, and a suggestion of inducing remission in such patients. Objective: To report our experience with cyclosporine in pediatric patients with CIU. Methods: Fifty‐four patients with CIU were referred to us during the period from 2000 through June of 2005. Seven of those, aged 9–16, failed therapy with high dose antihistamines even with the addition of alternate morning prednisone. Neoral brand of cyclosporine, 3 mg/kg/day divided b.i.d., was initiated in these patients. Cyclosporine serum concentrations, blood urea nitrogen (BUN), creatinine, and blood pressure were routinely monitored. Results: All had cessation of hives. This occurred after 1–4 weeks for six of the seven and 8 weeks for one. While some experienced relapses, all were eventually off of all medications and free of hives. None of the seven experienced any adverse effects. Conclusions: Our experience in children is consistent with a previous controlled clinical trial in adults and supports the efficacy and safety of cyclosporine for CIU. However, we recommend that it be reserved for those whose CIU that is resistant to conventional measures and that patients be carefully monitored with cyclosporine serum concentrations and measures of renal function.  相似文献   
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Rehabilitation and special education are usually conceived in terms of methods, gadgets, locations and professions. Generalist planners often have difficulty grasping the essentials of the field, while resource constraints in Third World countries severely limit the extent to which these four features may become widely available. Reconceptualization of the field as information-based rehabilitation opens new, low-cost possibilities for empowering disabled people and their families and communities. A basic approach is described from Pakistan, for methodical dissemination of appropriate information, with feedback, evaluation and on-going information systems. Some comparative merits of various media are discussed, together with the values inherent in information and some constraints on information-based rehabilitation.  相似文献   
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1. The motor unit, consisting of a single motor neuron and the skeletal muscle fibres that it innervates, is the final output pathway of the motor system. 2. Much is now known about the way that human motor neurons are recruited and controlled during voluntary and reflex movements. This review briefly summarizes some of the recent experimental data that has contributed to our present understanding. The review is largely limited to data obtained in human experiments. While much of what we know about the organization of the nervous system has come from studies of the anatomy and physiology of experimental animals, there are some questions that cannot be addressed in reduced animal preparations. The development of new techniques has made it possible to investigate the human nervous system at a level of detail that has not hitherto been possible.  相似文献   
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Etched track detectors are widely used for the detection of radon and its decay products. They have many desirable attributes: they are small, cheap, simple, non-toxic and non-hazardous. Etched track detectors provide adequate accuracy for most radiological protection purposes provided stringent quality assurance is maintained. The UK validation scheme provides an important component of QA but continuous monitoring of conditions and results is also needed. If these conditions are observed, these detectors provide an entirely adequate tool for large-scale use in assessing levels of radon in houses. Accurate estimates of long-term average radon levels require a measurement over several months because of the short-term fluctuations in radon concentrations.  相似文献   
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BACKGROUND: Vocal cord dysfunction (VCD) is an involuntary functional disorder commonly misdiagnosed as asthma. Previous reports describe the disorder and treatment but not the long-term outcome. OBJECTIVE: To determine the long-term outcome of VCD. METHODS: A retrospective medical record review identified 49 patients, ages 8 to 25 years, diagnosed as having VCD from 1989 to 2002. Telephone contact was attempted in all. RESULTS: Of the 49 patients, 41 had previously been treated for asthma; that diagnosis was confirmed by us as a comorbidity in only 12 patients. Two distinct phenotypes of VCD were observed. Symptoms were limited to exercise-induced VCD (EIVCD) in 29 and spontaneously occurring VCD (SVCD) in 20, only 4 of whom additionally had EIVCD. Twenty-eight of the 49 were successfully contacted by telephone. Eight of the 11 contacted patients with SVCD followed the recommendation to see our speech therapist, all of whom learned to control symptoms. However, 2 who also had EIVCD continued with that problem. Pretreatment with an anticholinergic inhaler prevented EIVCD in 6 patients in whom this was tried. Complete absence of symptoms, at times ranging from 1 week to 5 years (median, 5 months), was reported in 26 of the 28 contacted patients. CONCLUSIONS: VCD continues to be frequently misdiagnosed as asthma. Two phenotypes of VCD are apparent: EIVCD and SVCD. Speech therapy provides relief of symptoms for SVCD. Prevention of EIVCD with an anticholinergic inhaler in 6 patients suggests that a controlled clinical trial is warranted. Regardless of treatment, eventual spontaneous resolution was common.  相似文献   
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Objective: Our purpose was to determine whether insulin-like growth factors I and II preferentially stimulate uterine leiomyoma cells versus myometrial cells in monolayer culture.Study design: Leiomyomas and normal myometrium were obtained at hysterectomy from five premenopausal women. Specimens were enzymatically digested for use in primary monolayer cell cultures. By use of serum-free media, insulin-like growth factor I or II was added in 1, 10, and 100 ng/ml concentrations to both cell types with the patient serving as her own control. Cell number, prolactin production, and proliferative index values were measured on day 15 of cell culture.Results: Significant increases in cell number were found in the leiomyoma cultures (p < 0.05) treated with 10 and 100 ng/ml insulin-like growth factors I but not with insulin-like growth factos II. Neither factor exerted a stimulatory effect on myometrial cells.Conclusion: Insulin-like growth factor sI preferentially stimulates leiomyoma cells in monolayer culture. These results suggest an autocrine-paracine role in vivo for this factor in conjuction with gonadal steroids in promoting leiomyoma growth.  相似文献   
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