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排序方式: 共有1419条查询结果,搜索用时 15 毫秒
91.
92.
Obstructive sleep apnea: diagnosis with ultrafast CT 总被引:8,自引:0,他引:8
Patients with sleep-disordered breathing often have physiologic and anatomic abnormalities of the upper airway that are demonstrable while awake. An ultrafast computed tomographic (CT) scanner was used to measure the oropharyngeal and nasopharyngeal cross-sectional areas of 11 patients with obstructive sleep apnea. Twenty-four healthy volunteers served as control subjects. The percentage of change in cross-sectional area during quiet tidal breathing was used as a measure of airway compliance. Compared with weight-matched control subjects, patients with obstructive sleep apnea had smaller oropharyngeal airways (40.4 vs 177.8 mm2) (P less than .001) and smaller nasopharyngeal airways (31.3 vs 134.2 mm2) (P less than .001). In addition, their oropharyngeal airways were significantly more compliant (75% vs 27%) (P less than .001). Patients with obstructive sleep apnea are characterized by a small, collapsible oropharyngeal airway and by nasopharyngeal airway narrowing. These abnormalities can cause sleep-disordered breathing. Ultrafast CT scanning allows rapid, noninvasive assessment of airway variables. 相似文献
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OBJECTIVE: To prospectively document the prevalence of otitis media with effusion (OME) in 86 African-American children between ages 2 and 5 years. STUDY DESIGN: Eighty-six children in center-based child care whose ear status had been followed from infancy continued to be observed. Middle ear status was assessed by pneumatic otoscopy and tympanometry biweekly. RESULTS: The prevalence of OME decreased as children became older. The mean proportion of examinations demonstrating bilateral OME (BOME) ranged from 12% between 24 to 30 months to 4% between 54 to 60 months of age. The mean proportion of exams revealing bilateral normal ears increased from 77% at 24 to 30 months to 88% at 54 to 60 months of age. Although 60 children had experienced BOME that lasted 4 months or longer in the 6- to 24-month age period, only 8 of these children experienced at least 4 months of continuous BOME between 24 to 60 months. CONCLUSIONS: The proportion of time with BOME decreased progressively with increasing age in this population. Only 8 of 60 children who had experienced more than 4 consecutive months of BOME before 2 years of age continued to manifest persistent effusion or experience recurrences of prolonged BOME after 2 years of age. 相似文献
95.
Parathyroid adenomas in the aortopulmonary window 总被引:3,自引:0,他引:3
96.
The classification, epidemiology, pathophysiology, diagnosis, and treatment of ischemic cerebrovascular disease (ischemic stroke) are reviewed, and the major drugs used in the prevention of this disease are discussed. Ischemic stroke is a major problem in terms of morbidity and mortality because of the high prevalence of atherosclerosis in the United States population. The pathogenesis of cerebral ischemia is multifactorial, beginning with an atherosclerotic plaque on the arterial wall that may result in stenosis or ulceration with subsequent thrombosis or embolization. Platelets may adhere to the exposed arterial wall endothelium, stimulating further platelet aggregation and accumulation of leukocytes and fibrin. Consequences of cerebral ischemia include transient ischemic attacks and brain infarcts. Diagnosis is based mainly on patient history and ancillary radiologic studies. Treatment of ischemic cerebrovascular disease is primarily preventive, since the brain has limited capacity to recover neurologic function after an infarction. Transient ischemic attacks are treated with either antiplatelet agents, anticoagulants, or surgery. Treatment of stroke is also preventive, although anticoagulation is sometimes used to prevent stroke progression. Agents that may reverse neurologic impairment following an acute stroke, such as prostacyclin, calcium-channel blockers, and opiate antagonists, are being investigated. Antiplatelet therapy is indicated in subsets of patients with cerebral vascular insufficiency. Anticoagulation therapy, if needed, should be given for only three to four months. 相似文献
97.
A Nørremølle E Budtz-Jørgensen K Fenger JE Nielsen SA Sørensen and L Hasholt 《Clinical genetics》2009,75(3):244-250
Huntington disease (HD) is caused by an expanded CAG repeat sequence in the HD gene. Although the age at onset is correlated to the CAG repeat length, this correlation only explains approximately half of the variation in onset age. Less variation between siblings indicates that the variation is, in part, explained by genetic modifiers. We analyzed polymorphic loci within or close to the HD gene on the HD chromosome in Danish HD patients. We found one specific haplotype segregating with later age at onset, compared with patients with similar CAG repeat length and another haplotype. The nine Danish families in the study carrying this haplotype most likely have a common founder. Several of the polymorphic loci displayed alleles that may be specific to the late-onset haplotype, implicating that from this study we cannot determine which of the loci tested (or other polymorphic loci in this chromosomal area) do in fact contain genetic modifiers of age at onset. 相似文献
98.
JA Jackson MP Wailoo SA Petersen JR Thompson T Davies 《Acta paediatrica (Oslo, Norway : 1992)》2001,90(10):1186-1189
Aim : To investigate whether infants with intrauterine growth retardation (IUGR) experience different changes in temperature and cortisol excretion after routine immunization compared with normal healthy infants. Methods : Overnight deep body temperature and urinary cortisol to creatinine ratios were measured on the night after immunization and a control night in normal and IUGR infants. Results : In 60 normal infants, first vaccination at about 10 wk of age led to a significant increase in minumum overnight temperature compared to the control night, mean rise 0.25°C (95% CI, 0.12 to 0.38). In 35 IUGR infants the mean rise in temperature between immunization night and control night was 0.35°C (95% CI, 0.15 to 0.55). The increases in minimum temperature did not differ significantly between the normal and IUGR infants ( p = 0.11). Cortisol to creatinine ratios measured from overnight urine samples showed that 23 IUGR infants had consistently higher levels than 39 normal infants; control night medians 34 and 15 ( p = 0.01) and immunization night medians 56 and 26 ( p= 0.02), respectively. However, the percentage increase did not differ significantly between the IUGR infants and the normal infants. A smaller number of second immunizations were studied, but no significant differences were found.
Conclusion : These results suggest that although the impact of immunization is the same for IUGR and normal infants, because IUGR infants are less mature and at greater stress before immunization, the absolute levels that they experience after immunization are higher than those for normal infants. 相似文献
Conclusion : These results suggest that although the impact of immunization is the same for IUGR and normal infants, because IUGR infants are less mature and at greater stress before immunization, the absolute levels that they experience after immunization are higher than those for normal infants. 相似文献
99.
HA Miot LDB Miot PS Lopes GR Haddad SA Marques 《Journal of the European Academy of Dermatology and Venereology》2009,23(10):1173-1177
Background Palmoplantar pustulosis (PPP) discloses some differences compared to vulgar psoriasis (PV) in terms of age of onset, female predominance and low occurrence of psoriasis lesions elsewhere. Cigarette smoking has been associated to PPP in international studies; nevertheless, these studies were never performed among Brazilian.
Objectives To compare prevalence of smoking among PPP, PV and other dermatologic patients (NPD).
Methods Case–control study involving 25 PPP patients from a reference psoriasis centre. Two control groups were matched according to gender and age: 50 patients with PV and 50 NPD. Confounders were adjusted by conditional multiple logistic regression.
Results Among cases, 84.0% were female and PPP age of disease onset (41.4 years) was greater than PV (34.5 years). Prevalence of ever smoking was higher among cases (92.0%) than PV (52.0%) and NPD (30.0%). Adjusted odds ratio of PPP ever smoking compared to PV and NPD was 9.5 and 36.2, respectively. All smokers reported the onset of their habit before the development of PPP.
Conclusions There was significant association between PPP and smoking. However, the impact of giving it up in the clinical course of the disease remains to be established. 相似文献
Objectives To compare prevalence of smoking among PPP, PV and other dermatologic patients (NPD).
Methods Case–control study involving 25 PPP patients from a reference psoriasis centre. Two control groups were matched according to gender and age: 50 patients with PV and 50 NPD. Confounders were adjusted by conditional multiple logistic regression.
Results Among cases, 84.0% were female and PPP age of disease onset (41.4 years) was greater than PV (34.5 years). Prevalence of ever smoking was higher among cases (92.0%) than PV (52.0%) and NPD (30.0%). Adjusted odds ratio of PPP ever smoking compared to PV and NPD was 9.5 and 36.2, respectively. All smokers reported the onset of their habit before the development of PPP.
Conclusions There was significant association between PPP and smoking. However, the impact of giving it up in the clinical course of the disease remains to be established. 相似文献
100.