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991.
M B Taylor 《Postgraduate medicine》1991,89(8):40-2, 45-7
The spectrum of acne vulgaris is wide, ranging from minor comedones to devastating nodules and cysts. Appropriate therapy requires an understanding of the various types of lesions, their pathophysiology, and the rationale for treatment. Good patient rapport and communication are important, and close follow-up is necessary until the treatment regimen has stabilized. Timely referral to a dermatologist is essential when therapy is not effective. With effort, the treatment of acne can be quite rewarding for both patient and physician. 相似文献
992.
R W Deitrick 《The Journal of sports medicine and physical fitness》1991,31(3):367-375
A physiological comparison of the responses of typical weight (less than 90 kg) versus heavy weight (greater than 90 kg) male triathletes to maximal treadmill and maximal bicycle exercise was performed to better understand the effects of weight on endurance performance. The heavy triathlete group (90.9 +/- 3.2 kg, mean +/- SD) had significantly (p less than .01) greater percent body fat (11.9 +/- 3.6 vs 7.4 +/- 1.8%) while having significantly (p +/- .01) lower VO2max values expressed in ml.kg-1.min-1 on both the treadmill (55.6 +/- 4.1 vs 69.9 +/- 5.5) and bicycle ergometer (51.9 +/- 3.9 vs 60.5 +/- 6.2) than the typical triathlete group (66.6 +/- 5.9 kg). Analysis of covariance using body fat as the covariate resulted in persistent significant (p less than .02) VO2max (ml.kg-1.min-1) differences between the groups. Statistically significant (p less than .05) differences in running economy existed between the groups (33.7 +/- 2.7 vs 37.1 +/- 1.5 ml.kg-1.min-1; typical vs heavy). The heavy triathletes also had a significantly (p less than .01) shorter treadmill performance time (9.6 +/- 2.3 vs 13.2 +/- 1.7 min) and significantly (p less than .01) lower power per weight ratio on the bicycle ergometer (5.37 +/- 0.48 vs 6.47 +/- 0.59 watts/kg). These findings indicate that the heavy triathlete is at a physiological disadvantage when competing in endurance events and supports the inclusion of a weight category in these events. The reported triathlon results support these physiological findings. 相似文献
993.
R G Amedee W J Mann J M Gilsbach 《Archives of otolaryngology--head & neck surgery》1989,115(9):1103-1106
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
994.
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
995.
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
996.
997.
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
998.
999.
R S Mecklenburg 《The Diabetes educator》1989,15(1):40-43
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
1000.
C A González G López-Abente M Errezola A Escolar E Riboli I Izarzugaza M Nebot 《International journal of epidemiology》1989,18(3):569-577
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