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81.
Visual function and academic performance   总被引:1,自引:0,他引:1  
Evaluation of 1,910 first-, second-, and third-grade students indicated that visual function and academic performance as measured by reading were not positively related. Visual function tests included visual acuity, muscle balance, preferred eye and hand, color vision, refraction, sensory and motor function, and a writing and drawing task. Academic tests included the Metropolitan Readiness Test, the Cognitive Abilities Test, the Iowa Test of Basic Skills, and the teacher's assessment of reading level. A simple test which can be completed during the office visit and interpreted by the ophthalmologist in the office included drawing, copying, and writing. A segment of this test, the "draw a bicycle test," can be used by an ophthalmologist to demonstrate the difference between vision and performance when examining a child up to third-grade level who is referred because of school failure.  相似文献   
82.
Naproxen in prophylaxis of migraine   总被引:2,自引:0,他引:2  
Naproxen sodium is an inhibitor of platelet aggregation and prostaglandin synthesis and is also a potent anti-inflammatory agent. Because of these properties, it was evaluated in prophylaxis of migraine by a double-blind, placebo-controlled crossover study in 34 patients. Drug "preference" and therapeutic effect were rated by both patient and investigator. Overall, both preferred drug over placebo. An index of migraine activity was calculated from a daily record kept by the patient; it demonstrated a significant reduction in headache severity, duration, disability, and medication needed. Adverse effects were minimal and similar in drug and placebo. Naproxen is a promising agent in the prophylaxis of migraine.  相似文献   
83.
Four physicians comment on an issue paper from the Department of Health and Social Security about provisions of the Data Protection Act that would permit patient access to computerized health records in 1987 unless the Secretary of State rules otherwise. S. Jenkins, a general practitioner, fears that patient access would refocus the record on the doctor's best interests rather than the patient's. C.J. Dickinson, a medical professor, welcomes access as fostering trust. M.A. Heasman, a health administrator, opposes unrestricted access but urges physicians to reveal more to patients. B.W. Ellis, a consultant surgeon, holds that patients have a right to see their records, subject to physician discretion in disclosing information to the patient's general practitioner or other third party. An interprofessional working group's "Statement on subject access to personal health information" rejects unrestricted access lest it inhibit health professionals from recording sensitive data.  相似文献   
84.
The challenge of rehabilitating young, healthy transfemoral amputees may extend beyond the boundaries of teaching them to adapt to functional activities of daily living. The goal for several of these amputees is to participate and sometimes even compete in recreational activities, including running. These amputee runners require prosthetic adaptations as well as a comprehensive individualized training programme to ensure that their running is as safe and energy efficient as possible. To help amputees achieve this, clinicians must understand normal and prosthetic locomotion. This paper compares the biomechanical differences between walking and running in normal locomotion and analyses the running modes used by transfemoral amputees. The modified running mode achieved with the Terry Fox Running Prosthesis subjectively "looks" more energy efficient to the observer and "feels" more energy efficient to the user. These assumptions have yet to be confirmed or refuted by a rigorous scientific research study. An outline of the proposed physiotherapy protocol includes the familiarization, treatment, and training phases. Physiotherapists involved in amputation rehabilitation may not be commonly confronted with this level of patient expectation. It is their responsibility to give realistic guidance to these amputees so that they can safely and independently pursue their recreational running activities. This need can best be fulfilled by providing sound clinical advice which has been validated by research findings.  相似文献   
85.
Optimal payment systems for health services   总被引:6,自引:0,他引:6  
Demand-side cost sharing and the supply-side reimbursement system provide two separate instruments that can be used to influence the quantity of health services consumed. For risk-averse consumers, optimal payment systems--pairs of insurance and reimbursement plans--are characterized by conflict rather than consensus between patient and provider about the quantity of treatment. A model of conflict resolution based on bargaining theory is used to represent the outcome when the payment system creates divergences between desired demand and desired supply. Using that model, we describe the optimal combination of insurance and reimbursement systems that maximize consumer welfare.  相似文献   
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87.
Apoptosis, programmed cell death, occurs in a variety of cellular systems and in response to many different stimuli. One group of apoptosis inducers are glucocorticosteroids which are also found in the battery of cytotoxic drugs used to treat CLL. In the present study we have examined the potency of the glucocorticosteroid-dexamethasone to induce apoptosis in lymphocytes of patients with B-CLL. Lymphocytes of 15 nontreated patients and 5 controls were isolated and incubated for 24 h in the presence or absence of dexamethasone (2 mu M) Following incubation the cells were harvested and their DNA extracted. The extracted DNA samples were analysed for internucleosomal DNA cleavage by UV illumination after electrophoresis on agarose slab gel containing ethidium bromide. Five patients showed neither spontaneous nor dexamethasone induced apoptosis. Whereas, 10 patients, showed a dexamethasone-non-dependent spontaneous apoptosis which appeared 24 h after the start of incubation. The cells of these patients were the only ones to respond to dexamethasone showing an enhanced apoptosis effect. This study shows that apoptosis monitoring in CLL may provide important information regarding susceptibility of the cells to steroid induced apoptosis.  相似文献   
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The present report summarizes findings on 670 cases of autosomal trisomy diagnosed in Scotland, with actual or expected dates of delivery in 1990 to 1994 inclusive. Cases were notified by cytogenetic service laboratories. There were 277 prenatal and 369 postnatal diagnoses and 24 spontaneous losses. Excluding the latter, numbers diagnosed with trisomy 21, trisomy 18, trisomy 13, and other trisomies were, respectively, 470 (72.8%), 108 (16.7%), 36 (5.6%), and 32 (5.0%). Estimated maternal age-specific birth rates for trisomy 21 were close to published values from other jurisdictions. However, comparisons with a clinically based national register of congenital anomalies suggested that 3-4% of Down syndrome births were never karyotyped, most being early neonatal deaths. There was a striking increase over the period in the proportion of cases detected prenatally, associated with increased maternal serum screening in mothers <35 years old. Over the 3 final years (1992-1994), prenatal screening followed by elective termination was estimated to reduce the birth rate in trisomy 21 by 24% in mothers aged <35 years, by 57% in older mothers, and by 35% in all mothers. The crude incidence per 1,000 births fell from 1.08 in 1990-1991 to 0.77 in 1992-1994, in spite of an upward shift in the overall maternal age distribution. For trisomies 18 and 13, the estimated overall reductions in the birth rate over the whole 5-year period were respectively, 26 and 17%. In free trisomy 18, there was a significant reduction in the sex ratio (male/female) to 0.65, in line with earlier studies.  相似文献   
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