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41.
OBJECTIVE: The purpose of this study was to investigate the effects of therapy balls as seating on in-seat behavior and legible word productivity of students with attention deficit hyperactivity disorder (ADHD). Additionally, social validity was assessed to evaluate teacher and student opinions regarding the intervention. METHOD: A single subject, A-B-A-B interrupted time series design was employed across 3 students (2 males, 1 female) with ADHD. The study was conducted in a 4th grade inclusive classroom during daily language arts. During phases 1 and 3, the 3 participants and all other class members sat on chairs (in-seat on chair); during phases 2 and 4, everyone sat on therapy balls (in-seat on ball). Dependent variables were in-seat behavior and legible word productivity. Data were graphed and visually analyzed for differences between phases. RESULTS: Results demonstrated increases in in-seat behavior and legible word productivity for the students with ADHD when seated on therapy balls. Social validity findings indicated that generally the teacher and students preferred therapy balls. CONCLUSION: This study provides evidence that use of therapy balls for students with ADHD may facilitate in-seat behavior and legible word productivity.  相似文献   
42.
43.
BACKGROUND: It is common for older patients to present to accident and emergency (AE) departments after a fall. Management should include assessment and treatment of the injuries and assessment and correction of underlying risk factors in order to prevent recurrent falls. OBJECTIVES: To determine management of older patients presenting after a fall to the AE department of Groote Schuur Hospital in Cape Town, South Africa. METHOD: Hospital records were reviewed for a random sample of 100 patients aged 65 years and older presenting to the AE department after a fall, between December 2001 and May 2002. RESULTS: The mean age of the sample was 78.6 years (range 65-98 years); 72% of subjects were female. History of a previous fall, and history of drug or alcohol intake, were recorded in less than 20% of cases. Blood pressure and pulse rate were recorded in approximately 90% of cases, and pulse rhythm and postural blood pressure in 2%. Examination of the musculoskeletal system was done in 86% of cases and that of other systems in less than 50%; cognitive assessment was conducted in less than 30%. Radiological investigations were performed in 89% of cases, glucose and haemoglobin in 32%, renal profile and electrocardiogram in 5%, and urinalysis in 4%. Three-quarters of the patients were referred for further management: 52% to orthopaedic surgery, 12% to other surgical subspecialties, 6% to the general medical department, and 6% to other hospitals and clinics. No referrals were made to geriatric medicine, physiotherapy or occupational therapy. CONCLUSIONS: In managing elderly patients after a fall, the AE department focused on injuries sustained. Little effort was made to establish and manage risk factors, hence to prevent recurrent falls. Guidelines are needed for the management of such patients in AE departments.  相似文献   
44.
To date, there is no clinicopathological correlation of adrenal medullary transplant cases in patients with survival beyond a few years. Postmortem examination of a brain from a patient with Parkinson's disease (PD), 16 years after autologous adrenal medullary transplant, was performed using tyrosine hydroxylase (TH) and chromogranin A. The patient experienced a four-year initial improvement in motor function followed by resumption of the progressive nature of her disease that continued until her death. She expired 16 years following grafting. At autopsy, TH stain of the brain revealed severe loss of TH-immunoreactivity in the substantia nigra and Lewy bodies, confirming the diagnosis of PD. The transplant site was identified by the presence of scarring and there was complete absence of any TH staining cells at the site of the transplant. There were few surviving cells staining with chromogranin A. The absence of TH-staining cells in the transplant 16 years after surgery provides further evidence that adrenal medullary transplants do not survive in the long term.  相似文献   
45.
Many hormones, neurotransmitters and growth factors influence their target cells by activation of mitogen-activated protein kinase cascades. The consequences of such activation reflect not only the magnitude, but also the kinetics and cellular compartmentalization of kinase activity. Gonadotropin-releasing hormone (GnRH) receptors are seven-transmembrane receptors that have undergone a period of rapidly accelerated molecular evolution in which the advent of type I mammalian GnRH receptors has been associated with the loss of the carboxyl-terminal tail, a structure present in all other seven-transmembrane receptors. Here, we review spatiotemporal aspects of extracellular-signal-regulated kinase activation by gonadotropin-releasing hormone receptors, emphasizing how the absence or presence of the carboxyl-terminal tail dictates the receptors' ability to engage and signal via arrestins.  相似文献   
46.
Objective Detection of HPV DNA in oral and genital lesions of a heterosexual male. 4 months after oral and vaginal intercourse with a woman with vulvar warts. Passible modes of acquisition of oral HPV infection in the male sexual partner are discussed. Setting Genitourinary Medicine clinic. Methods Polymerase chain reaction amplification of genomic DNA from oral and genital lesions. HPV DNA typing by dot blot hybridization. Results HPV DNA types 6 and 11 were identified in a polypoid tongue lesion and in a penile wart from the male sexual partner. Conclusions The acquisition of oral HPV infection in the male sexual partner may have resulted from genital-oral HPV transfer, either by direct contact with vulvar warts or by digital self-inoculation.  相似文献   
47.
Little is known about oral health care behaviors of community-dwelling, cognitively impaired elderly (CIE) persons. Few studies have been conducted regarding the actual provision of oral care for CIE persons or the attitudes and concerns about oral health among their caregivers. The CIE person's ability to perform self-care decreases over time, and the role of the caregiver in daily oral care becomes increasingly important. The purpose of this pilot study was to explore the attitudes toward oral health and identify related concerns among caregivers who care for community-dwelling CIE persons. Caregivers were surveyed by means of a self-administered, mailed questionnaire. To maintain confidentiality, an intermediary was used for recruitment and data collection. Overall, 148 caregivers were invited by an intermediary to participate in the survey; only 21 (14%) consented to participate and returned the questionnaire. This paper discusses some of the numerous methodological challenges identified when an attempt was made to survey caregivers' attitudes toward and barriers to providing oral care for a dependent CIE.  相似文献   
48.
Background: Ketamine is a potent bronchodilator that, in clinically used concentrations, relaxes airway smooth muscle in part by a direct effect. This study explored the role of calcium concentration (Ca2+) in this relaxation.

Methods: Canine trachea smooth muscle strips were loaded with the fluorescent probe fura-2 and mounted in a spectrophotometric system to measure force and intracellular calcium concentration ([Ca2+]i) simultaneously. Calcium influx was estimated using a manganese quenching technique. Cyclic nucleotides in the airway smooth muscle strips were measured by radioimmunoassay.

Results: In smooth muscle strips stimulated with submaximal (0.1 micro Meter) and maximal (10 micro Meter) concentrations of acetylcholine, ketamine caused a concentration-dependent decrease in force and [Ca2+]i. The sensitivity of the force response to ketamine significantly decreased as the intensity of muscarinic receptor stimulation increased; the median effective concentration for relaxation induced by ketamine was 59 micro Meter and 850 micro Meter for tissue contracted by 0.1 micro Meter or 10 micro Meter acetylcholine, respectively (P < 0.05). In contrast, the sensitivity of the [Ca2+] sub i response did not depend on the intensity of muscarinic receptor stimulation. Ketamine at 1 mM significantly inhibited calcium influx. Ketamine did not significantly increase cyclic nucleotide concentrations.  相似文献   

49.
Motor vehicle rollover and static stability: an exposure study.   总被引:1,自引:0,他引:1       下载免费PDF全文
OBJECTIVES: This study examined vehicle rollovers in terms of site-specific exposure and speeds of vehicles of varying stability. METHODS: Fifty-one rollover sites in two states were visited at the same time of day and day of week as the rollover. A sample of vehicles moving in the same direction as the rollover were observed, and vehicle-specific data were obtained from identification numbers. RESULTS: Low stability, exacerbated by the addition of passengers, increased the risk of rollover. Speed was not correlated with stability and is not a confounder. CONCLUSIONS: Rollovers could be substantially reduced if motor vehicles were manufactured with a static stability of 1.2 or greater.  相似文献   
50.
To understand the potential early responses of human bone and the calcium endocrine system to spaceflight, we studied 8 healthy men, aged 35-44 years before, during, and after bed rest in a -6 degrees head-down tilt model for microgravity. Based on a novel single-dose labeling schedule, average rates of bone formation in the iliac crest were reduced in 6, unchanged in 1, and increased in 1 following the bed rest period. The decrease was greatest for subjects whose daily walking miles were highest (r = -0.762, p less than 0.05, n = 7). Before a measurable increase in ionized serum calcium the sixth bed rest day, there was increased excretion of urinary calcium and sodium, evident the first 2 bed-rest days and parallel for the entire week (r = 0.92, p less than 0.001). Reduced excretion of phosphorus and 3', 5' cyclic adenosine monophosphate on the first and second bed rest days was followed by an increase in serum phosphorus by the sixth bed rest day. Depressed serum concentrations of parathyroid hormone and 1,25-dihydroxyvitamin D were manifest by the sixth and seventh bed rest days. The similarity of the response of bone and the calcium endocrine system of healthy men after only 7 days to results of longer term bed rest studies emphasizes the responsiveness of the adult human skeleton to biomechanical stimuli induced by changes in activity and/or position.  相似文献   
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