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991.
The anatomic principles and operative techniques currently applied to functional endoscopic endonasal surgery have allowed for significant refinements in another approach to regional pathology that uses the operating microscope, newly designed sinus instruments, and a self-retaining nasal speculum system. The main benefits of this method are the superb widefield stereoscopic vision and the distinct freedom to work bimanually. Additionally, direct bipolar cautery of bleeders is afforded while use of the observer tube or video allows for excellent teaching. The precise nature of this surgery affords less fear of serious complications in the treatment of periorbital, paranasal sinus, and parasellar diseases. We describe technical aspects of the surgery and associated complications in 219 patients treated from 1984 to 1987.  相似文献   
992.
We found that thirteen per cent of all head and neck malignomas are malignant lymphomas. In 75% of these cases the Non-Hodgkin type could be found. The major salivary glands were involved by the lymphoma in 55% out of 104 patients. Paraglandular lymph nodes of the parotid gland were affected as well as intraglandular lymph nodes and the lymphoid tissue within the gland proper. The submandibular gland normally shows an involvement only with its paraglandular lymph nodes. Two thirds of the Non-Hodgkin lymphomas located in the salivary glands were low-grade. In case of clinical suspicion of a malignant lymphoma, fine needle biopsy is required for cytological diagnosis. However, surgery is mandatory for histological diagnosis, not as a therapeutic measure.  相似文献   
993.
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   
994.
995.
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   
996.
Occupation and bladder cancer in Spain: a multi-centre case-control study   总被引:5,自引:0,他引:5  
A case-control study on bladder cancer was carried out in four regions of Spain. The study included 497 cases (438 males and 59 females), 583 hospital controls and 530 population controls matched by sex, age and residence. The present paper reports the results of the analyses on occupational history. Among men, an increased risk of bladder cancer was found for textile workers (OR = 1.97, 95% CL 1.2-3.3), mechanics and maintenance workers (OR = 1.86, 95% CL 1.2-2.8), workers in the printing industry (OR = 2.06, 95% CL 1.0-4.3) and for managers (OR = 2.03, 95% CL 1.2-3.5). The risk was highest among those first employed in the textile industry before the age of 25 and prior to 1960. Among mechanics the risk was highest for those who started after the age of 25 and later than 1960. The OR for smokers who had also been employed in one of the high risk occupations was 7.82 (95% CL 4.4-14.0) which is compatible with a multiplicative effect of joint exposure to tobacco and occupational hazards.  相似文献   
997.
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   
998.
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   
999.
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   
1000.
The activity of LCAT (the controlling enzyme for cholesterol esterification in plasma) is known to be reduced in alcoholic cirrhosis, while little is known about early stage (liver steatosis) alcoholics. In this study, LCAT activity was assayed by Stokke and Norum's method, before and after a 15-day sobriety period, in liver steatosis and in cirrhosis alcoholics. Before alcohol withdrawal, LCAT activity was depressed in both groups. After the sobriety period, LCAT activity was significantly raised in liver steatosis patients, but was still lower than in controls; in cirrhosis patients, it was increased, but not significantly. According to our results, LCAT activity impairment in alcoholic liver disease is sustained by both the hypothesized mechanisms, alcohol-related metabolic disorders and lowered LCAT-enzyme production, but to different degrees, depending on the stage of the disease. In liver steatosis, metabolic disorders play a major role, as a liver-impairment-induced decrease in LCAT production seems rather unlikely, and increased LCAT activity is more likely to be sustained by metabolic normalisation than by any recovery of the damaged liver. However, the lack of improvement in about 20% of patients, and the fairly wide scattering of individual data, suggest a minor LCAT production impairment in liver steatosis too. In cirrhosis, the major role seems to be played by a permanent decrease in LCAT production, as no significant rise in LCAT activity was observed after alcohol withdrawal. However the restored LCAT activity observed in some patients could be related to improvement in the metabolic disorder, thus confirming the effectiveness of this mechnism in cirrhosis too.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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