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71.
The prevalence of wheezing in children varies widely around the world. The reasons for this geographic variability remain unclear but may be related in part to exposures in the home environment during pregnancy and early childhood. We investigated the prenatal and early childhood risk factors for wheezing symptoms among 2127 children aged 6–8 years who were participants in the Ukrainian component of the European Longitudinal Study of Pregnancy and Childhood (ELSPAC). Cases included the 169 children whose parents answered yes to the International Study of Asthma and Allergy in Children (ISAAC) question: 'Has your child had wheezing or whistling in the chest in the past 12 months' during the ELSPAC assessment of the children at age 7. These were compared with the 1861 children in the cohort whose parents answered 'no' to this question.
Factors significantly associated with increased risk of wheezing illness at age 7 in adjusted analyses included mother's asthma [adjusted odds ratio (OR) 3.46, 95% confidence interval (CI) 1.22, 9.85]; mother's allergy problems (OR 1.43, [1.00, 2.05]); rarely playing with other children at age 3 (OR 1.84, [1.09, 3.11]); water intrusion (OR 1.62, [1.09, 2.39]) and inadequate heating of the home (OR 1.52, [1.06, 2.16]) during pregnancy. Factors protective of wheezing at age 7 included being first-born (adjusted OR 0.70, 95% CI 0.50, 0.98); living in the city of Dniprodzerzynsk as compared with Kyiv (OR 0.36, [0.24, 0.54]) and weekly contact with furry animals (OR 0.44, [0.20, 0.97]) before age 3. The constellation of risk factors for wheezing in Ukrainian children is similar to that of children in other parts of the world. Known risk factors do not account for the significant between-city variability of wheezing in Ukrainian children.  相似文献   
72.
73.
Hypocarotenemia in patients fed enterally with commercial liquid diets   总被引:1,自引:0,他引:1  
We have found that 12 patients requiring permanent enteral feeding secondary to cerebrovascular accident with adequate Vitamin A nutritional status had serum concentrations of various carotenoids which were only 8-17% of sex- and age-matched healthy controls. Their serum retinol levels were normal, but only 61% of their controls despite receiving two to three times the recommended daily allowance (RDA) in retinol equivalents. Commercial enteral formulas were found to contain only negligible quantities of the carotenoids and were the cause of the hypocarotenemia. To assess the ability of these patients to absorb beta-carotene, nine tube-fed patients were given 15 mg of beta-carotene (2.5 times the RDA) in a single dose. Serum concentration time curves showed that only four patients absorbed significant quantities of the beta-carotene and absorption was delayed compared to previously studied subjects taking enteral formulas as meals. These studies suggest that the efficiency of absorption of the fat soluble vitamins may be lower in tube-fed patients and that patients receiving long-term tube feeding are denied the possible protective effects of the carotenoids normally contained in the American diet.  相似文献   
74.
Results of revision total knee arthroplasty performed for aseptic loosening   总被引:2,自引:0,他引:2  
One hundred thirty-seven revision total knee arthroplasties (TKA) performed in 117 patients with failed aseptic metal-to-plastic knees over ten years (1974-1984) were studied to determine the long-term clinical and roentgenographic results and were compared to primary TKA. The mean age was 65 years (range, 32-90 years). Fifty-three percent had rheumatoid arthritis, and 47% had osteoarthritis. The mean interval from initial to revision TKA (129 knees) was four years (range, three months to 11 years) and from the first to second revision (seven knees) was 2.4 years (range, seven months to 5.5 years). The most common reasons for failure were loosening (73%), patellar complications (13%), and instability (10%). The mean follow-up time was 5.2 years (range, two to 12 years). Function, instability, motion, and pain all improved after revision TKA, but these improvements were significantly less than those seen after primary TKA. One-third of the patients still ambulated with crutches, a walker, or not at all. While mean postoperative flexion was 100 degrees, 24% could not flex to 90 degrees. Most patients (90%) were malaligned at the time of failure and remained so after revision (78%). The increased incidence of radiolucent lines (tibial, 61%; femoral, 24%) was not related to increased failure. Complications were not increased over primary TKA. The failure rate was 5.8% at 5.2 years, or approximately 1% per year. A successful clinical result was defined as a knee with mild or no pain, mild or no instability, and flexion to at least 90 degrees.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
75.
Conventional therapy for brain tumors, consisting of neurosurgical intervention and radiotherapy, has not resulted in the successes achievable in other childhood malignancies. The role of adjuvant chemotherapy, well defined in many childhood cancers, has not yet contributed significantly to the treatment of children with brain tumors. Chemotherapy of recurrent tumors has produced regressions but no cures. The most active agents identified to date in the treatment of recurrent posterior fossa tumors include cisplatinum, cyclophosphamide and methotrexate. Future efforts will need to focus on the rational selection of drugs for study in limited agent histology-stratified phase II trials, with advancement of active agents into large randomized phase III adjuvant therapy trials.  相似文献   
76.
77.
Deficits in visual-spatial ability can be associated with Parkinson's disease (PD), and there are several possible reasons for these deficits. Dysfunction in frontal-striatal and/or frontal-parietal systems, associated with dopamine deficiency, might disrupt cognitive processes either supporting (e.g., working memory) or subserving visual-spatial computations. The goal of this study was to assess visual-spatial orientation ability in individuals with PD using the Mental Rotations Test (MRT), along with other measures of cognitive function. Non-demented men with PD were significantly less accurate on this test than matched control men. In contrast, women with PD performed similarly to matched control women, but both groups of women did not perform much better than chance. Further, mental rotation accuracy in men correlated with their executive skills involving mental processing and psychomotor speed. In women with PD, however, mental rotation accuracy correlated negatively with verbal memory, indicating that higher mental rotation performance was associated with lower ability in verbal memory. These results indicate that PD is associated with visual-spatial orientation deficits in men. Women with PD and control women both performed poorly on the MRT, possibly reflecting a floor effect. Although men and women with PD appear to engage different cognitive processes in this task, the reason for the sex difference remains to be elucidated.  相似文献   
78.
79.
We examined the relationship between testosterone levels, violent dreams, and REM sleep behavior disorder (RBD) in 31 men with Parkinson's disease (PD): 12 with clinical RBD and 19 without. All PD patients with clinical RBD experienced violent dreams, but none of the 19 non-RBD patients reported violent dreams. While dream content appears to be more aggressive in PD patients with clinical RBD, the presence of violent dreams or clinical RBD is not associated with testosterone levels in men with PD.  相似文献   
80.
S G Friedman 《Surgery》1990,107(2):153-155
Duplex imaging has been widely embraced as a safe and an accurate means of interrogating the extracranial carotid vessels. One reason for this is its appearance as a risk-free diagnostic tool. We report the cases of two patients in whom transient ischemic attacks developed during duplex imaging--attacks that began soon after application of the ultrasound transducer to the cervical region, were identical to prior attacks, and ceased within seconds of removal of the transducer from the neck. The underlying cause of this complication is discussed as is its proper management.  相似文献   
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