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951.
Monaural loudness balances were performed by eight normal-hearing subjects to determine the effect of click repetition rate on loudness sensation. Click trains of 500 msec duration were matched in loudness to a standard 500 msec 1000 Hz tone burst presented at three reference loudness levels (70, 80, and 90 phons). Click trains were presented at repetition rates of 11, 31, 51, and 91 clicks per sec. It was found that click trains at faster repetition rates required lower intensities for judgments of equal loudness sensation. This finding was attributed to the process of temporal loudness summation. The magnitude and nature of the temporal summation process as well as the influence of the reference loudness level are discussed.  相似文献   
952.
To assess the adequacy of the nutritional care provided, a prospective noninterventional study was carried out on 250 randomly selected patients aged 65 and over who were admitted to a Veterans Administration Hospital. Of this group, 97 patients (39%) were found to be at high risk of having clinically significant protein-energy malnutrition. In 43 cases (17%), an assessment of the patient's nutritional status was not possible because the available data were inadequate. No patient had a diagnosis of malnutrition recorded on the problem list. Only 13 percent of the high-risk patients received some form of nutrition support therapy; 10 (10%) received oral supplements, and four (4%) were started on enteral feedings. Patients who received enteral feedings experienced a high rate of complications resulting from use of the feeding tubes. Over all, none of the high risk study patients received optimal nutrition support therapy. These findings indicate that elderly patients hospitalized in the Veterans Administration hospital in this study are usually not screened appropriately for protein-energy malnutrition, the diagnosis is frequently missed or ignored, and nutrition support therapy is underutilized and often ineffectually managed.  相似文献   
953.
Between June and September, 1986, an outbreak of measles occurred in Pilkhi Primary Health Centre area (population 56,000) in Tehri Garhwal district, Uttar Pradesh, India. Overall, 1092 cases were identified and 62 died; case-fatality ratio was 5.7%. Illness was restricted primarily to children below 15 years of age; 38% cases were in children under 5 and 58% between 5-14 years of age. To better characterize the outbreak, a survey was conducted in 13 affected villages. The age of the cases ranged from 5 months to 19 years (median = 7.0 years). The age-specific attack rates were 22.4%, 54.5%, 46.2% and 35.3% for children under 1, 1-4, 5-9, 10-14 years of age respectively. In as many as four villages, the attack rate in children below ten was 80% or more. Secondary attack rate among family members was 70%. Overall, 82% of children with measles developed complications which consisted mainly of pneumonia, diarrhoea and dysentery. The age-specific case-fatality ratios in infants and children 1-4 years of age were 23.1% and 11.5% respectively; thereafter the rates tended to decline with increasing age and was higher in females than in males (less than 0.05). Pneumonia which was a complication in 39% of measles cases contributed to 56% of deaths. Traditional beliefs and customs in the area were strong and did not encourage treatment of measles cases. Although a measles vaccination programme has been launched in India since 1985, only 30 districts could be covered during the first year and another 90 during 1986.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
954.
955.
Because insulin pump therapy is capable of providing insulin both at a slow continuous basal rate and in boluses, it more closely approximates physiologic insulin secretion than is possible with other methods of insulin administration. However, several short-comings are specifically related to the way insulin is delivered by pumps. These include increased risk of diabetic ketoacidosis and increased likelihood of infection at injection sites. The risk of hypoglycemic coma is apparently no greater with pump therapy than with conventional injections. Health professionals using pump therapy need a good working knowledge of the technical details as well as of the risks and benefits, and must be prepared to provide comprehensive training to their patients, particularly in the practice of frequent self-monitoring of blood glucose levels.  相似文献   
956.
957.
Free light chains in multiple sclerosis and infections of the CNS   总被引:1,自引:0,他引:1  
C DeCarli  M A Menegus  R A Rudick 《Neurology》1987,37(8):1334-1338
The intrathecal humoral immune response was analyzed in 83 patients with MS and 35 patients with acute CNS infections. CSF free kappa chains and CSF free lambda chains were quantified by radioimmunoassay; CSF IgG and albumin were measured by electroimmunodiffusion. The MS patients were characterized by higher levels of free kappa chains; free kappa:free lambda chain ratio; free kappa chain:albumin ratio; and IgG:albumin ratio. There were no differences in the level of free lambda chains or absolute concentration of IgG. A significant correlation was observed between free kappa chains and total IgG in MS and between free lambda chains and total IgG in infections, suggesting that the immune response was predominantly IgG-kappa in MS and IgG-lambda in infections.  相似文献   
958.
Plasma beta-endorphin immunoreactivity during graded cycle ergometry   总被引:1,自引:0,他引:1  
The present study was undertaken to define the response of plasma beta-endorphin immunoreactivity (ir-BE) to exercise of increasing intensity. Nineteen healthy males performed continuous exercise for 32 min on a cycle ergometer, comprised of 8-min bouts at %VO2max approximating 25, 50, and 75% of maximal exercise. Venous blood samples were collected before exercise (T = -20 and 0 min), during exercise (T = 8, 16, 24, and 32 min), and in recovery (T = +15, +30 min). Ir-BE in plasma was measured by radioimmunoassay using Immuno Nuclear assay kits. Plasma ir-BE level (pg X ml-1) was not altered from pre-exercise (18.3 +/- 1.3) after 8 min of exercise at 25 and 50% VO2max intensity; however, ir-BE rose significantly after 8 min of 75% VO2max work intensity (27.1 +/- 2.4) and was further elevated at maximal exercise (74.1 +/- 8.6). Ir-BE level remained elevated 15 min (60.9 +/- 8.1) and 30 min (35.2 +/- 5.2) post-exercise. The response pattern was further characterized by a significant (P less than 0.05) inter-individual variation, both at rest and during exercise; also, regression analysis indicated the ir-Be levels attained at maximal exercise were inversely related to the relative VO2max (ml X kg-1 X min-1) of the subject (predicted ir-BE = 248.2 - 3.39 VO2max; r = -0.397, P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
959.
Thirty gallium scans, using currently acceptable dosage levels (5-6 mCi) and a conventional rotating gamma camera, were performed on 20 patients with lymphoma or infection. Compared to planar scans, SPECT increased sensitivity and lesion detection from 48% to 89% in lymphoma, and from 50% to 80% in infection. The predictive value of a negative site was 81% in lymphoma and 67% in infection. Gallium utility is markedly increased by SPECT imaging. A normal gallium SPECT scan is highly accurate in ruling out disease.  相似文献   
960.
A case of testicular cancer in 2 brothers is reported and a review of the literature about testicular malignancies and etiologic factors in closely related family members is given. The familial incidence of testicular tumor is found to be 3% in twins and 0.6-2.1% in less closely related men. Tumors were of the same histology in 70-77% of the twins, whereas in brothers and in other degrees of relationship tumors of different histology mostly occur. Following the diagnosis of the tumor in the first man, the average interval to presentation of the tumor in the relative was 3.7 years in twins, 7.7 years in nontwin brothers and 13.5 years for less closely related men. The need for a thorough checkup of other family members is advised.  相似文献   
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