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991.
A new surgical technique for the treatment of recurrent temporomandibular joint subluxation or dislocation is described. Following a horizontal osteotomy and down-fracture of the articular eminence an inter-positional bovine cartilage xenograft is inserted in order to augment the vertical height of the eminence. The procedure combines simplicity with minimal post-operative morbidity. The increase in eminence height is both predictable and stable.  相似文献   
992.
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   
993.
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   
994.
A study was conducted to evaluate the efficacy of family history factors as screening criteria for childhood hypercholesterolemia. When they were seen for routine care at one of eight office practices, 1005 prepubertal children underwent random serum cholesterol determinations. Parental and grandparental histories of cardiovascular risk factors and atherosclerotic complications prior to 55 years of age were also obtained. Of the initial group, 274 children had total cholesterol levels greater than or equal to 175 mg/dL, and 175 of these children returned for retesting after an overnight fast. A total of 88 children were found to have low-density lipoprotein-cholesterol (LDL-C) values greater than or equal to 90th percentile for age and sex. Maternal and paternal histories of hypercholesterolemia were significantly associated with elevated LDL-C (odds ratio = 7.3 and 2.9, respectively), but had extremely low sensitivities (0.09, 0.15) despite modest positive predictive values (0.42, 0.22). Grandparental histories of sudden death, peripheral vascular disease, and gout were associated with elevated LDL-C, but sensitivities and positive predictive values for all of these factors were less than 0.22. Family history factors most commonly recommended as criteria for cholesterol screening in children did not identify half of all the children with elevated LDL-C and did not selectively identify the most severely affected children. Adding information concerning the presence of childhood obesity did not result in appreciable improvement in LDL-C detection beyond that achieved by family history factors alone. It was concluded that if thorough identification of young children with elevated LDL-C is desired, inclusive population screening rather than a family history-based strategy would be the most effective approach.  相似文献   
995.
Pyoderma gangrenosum and related disorders   总被引:2,自引:0,他引:2  
Pyoderma gangrenosum (PG) is an uncommon ulcerative cutaneous condition with distinctive clinical characteristics and a frequent association with systemic diseases. Most frequently among the associated disease list are: inflammatory bowel disease, arthritis, and a variety of hematologic disorders. There is no specific treatment of PG; however, the effective treatment of an accompanying systemic disease, local therapy, and/or the use of topical or systemic agents known to be useful in neutrophil disorders, have been beneficial in most patients.  相似文献   
996.
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   
997.
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   
998.
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   
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