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991.
The presence of anatomical endonasal variants (concha bullosa, nasal septal deviation, or hypertrophic turbinates) may cause more complications in patients with epiphora who have external dacryocystorhinostomy (DCR). The purpose of this study was to assess the results of surgical placement of a stent in 28 patients. They were randomised into two groups and had either DCR or placement of a Song's polyurethane stent. They were followed up for 18 months. Twenty-six patients had a good result. The success rate was 13/14 for those who had DCR and 13/14 for those who had a stent. Operating time was significantly less for placing a stent (mean (SD) 15 (2) minutes) compared with 40 (3) minutes for DCR (p <0.01). Placement of a polyurethane stent is an effective and short procedure for nasolacrimal obstruction, which is suitable for patients with unusual intranasal conditions.  相似文献   
992.
The toxic effects of cocaine are becoming more widely recognized as the popularity of the drug increases. Although overdose is usually fatal, treatment is available for users who experience agitation, seizure, arrhythmias, severe hypertension, or other side effects. Hospital admission is often necessary to allow monitoring of the acute situation. Initial management involves standard life-support measures. Therapeutic agents are given, as appropriate, both to control acute reactions and to counteract continuing toxicity.  相似文献   
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Two unrelated patients, a woman aged 44 and a man aged 56, with a type I neurofibromatosis, showed comedo-like formations at the top of some neurofibromas. One of them was excised in each case and they were studied histopathologically. The comedo-like formation of the first case mimicked the epithelial component of a fibrofolliculoma, and that of the second case had the structure of a primary late microcomedo and showed also anagen hair differentiation in the form of a follicular bulb and papilla. Both events are considered to be the result of a stimulation phenomenon and to reflect the essential role of the stroma in many cutaneous epithelial hyperplasias, hamartomas and possibly in some neoplasms.  相似文献   
995.
AIM: To analyze whether dry eye symptoms and ocular surface parameters change during different phases of the menstrual cycle. METHOD: Twenty-nine women of fertile age and with regular, 26-29-day menstrual cycles were included in the study. Fourteen subjects suffered and 15 did not suffer from dry eye symptoms. Symptoms were scored by the validated Ocular Surface Disease Index questionnaire. Tear production was evaluated with the Schirmer I test and the Schirmer II test (Jones test); tear stability with tear breakup time and Ferning test; and degree of dryness by the tear function index and imprint conjunctival cytology. Degree of inflammation was evaluated with conjunctival brush cytology and concentration of exudated serum albumin in tears. Hormonal cytology procedures were applied to exfoliated cells in tears. Patients were analyzed during menstruation, in the follicular phase and the luteal phase over two consecutive cycles, and results were statistically evaluated. RESULTS: Subjective symptoms, tear production and stability, surface dryness and inflammation were significantly related to hormonal fluctuations in the menstrual cycle. In particular, the impairment of these functions appeared to be related to the estrogen peak occurring during the follicular phase, especially in patients with dry eye. CONCLUSION: The ocular surface is confirmed to be an estrogen-dependent unit; clinicians should take into account these cyclic variations during examination of subjects affected by symptoms of eye dryness.  相似文献   
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998.

Background  

Mortality from invasive meningococcal disease (IMD) has remained stable over the last thirty years and it is unclear whether pre-hospital antibiotherapy actually produces a decrease in this mortality. Our aim was to examine whether pre-hospital oral antibiotherapy reduces mortality from IMD, adjusting for indication bias.  相似文献   
999.
Bone mass measurement (BMM) is useful to identify persons with low bone mass who are at increased risk for fracture. Given the increased emphasis that is being placed on preventive services such as screening for osteoporosis, we evaluated trends in BMM among Medicare beneficiaries. We studied a 5% sample of Medicare beneficiaries ≥65 yr of age in 1999–2005. We identified claims for BMM tests performed in both facility and nonfacility settings, evaluated temporal trends in use of these tests, and described the proportion of tests attributable to each specialty of physicians submitting claims. We also assessed patterns of serial testing among individuals who were tested more than once. Claims data from all years were pooled to describe the proportion of persons in the population ever tested. From 1999 to 2005, use of central DXA increased by ~50%, and use of peripheral DXA declined. The greatest increases in central DXA occurred among internists, family practitioners, and gynecologists. In 1999, the proportion of 65‐yr‐old women tested was 8.4%; this increased to 12.9% in 2005. Corresponding proportions for men were 0.6% and 1.7%, respectively. Between 40% and 73% of persons receiving central DXA were retested, most at ~2‐yr intervals. Aggregating data across all years for whites and blacks, 30.0% of women and 4.4% of men underwent central DXA at least once. We conclude that, although use of DXA steadily increased from 1999 to 2005, only ~30% of women and 4% of men at least 65 yr old had a central DXA study. Given the importance of central DXA to assess the risk of osteoporotic fractures, strategies to increase central DXA use to test at‐risk persons are warranted.  相似文献   
1000.
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