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101.
In March 1999, an outbreak of gastroenteritis occurred affecting 30 day-care centres served by the same caterer. A retrospective cohort study was performed in 13 randomly selected day-care centres to determine the source and mode of transmission. Electron microscopy and PCR were used to verify the diagnosis. The overall attack rate (AR) was 37% (195/524): 30% in children and 62% in adults. Modified by the age of the patient, eating pumpkin salad served on 1 March was associated with becoming an early case (odds ratio = 3.9; 95% confidence interval 1.8-8.8). No significant association was found between food consumption and becoming a late case. The primary food-borne AR was 27% and the secondary AR was 14%. The same genotype of Norwalk-like virus was found in 5 cases and in 1 ill and 1 asymptomatic food-handler. Contamination by 1 of the food-handlers seems the most likely route of spread of the virus and underlines the importance of strict hygienic routines.  相似文献   
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Two different internal fixation techniques for closed displaced fractures of the olecranon were evaluated at a mean of 18 years after injury. Thirty-two of the patients received tension-band wiring, and 35 received figure-of-eight wiring. There were 41 women (mean age, 52 years) and 26 men (mean age, 32 years) included. The results revealed that 80% of the patients had no subjective complaints, 16% had occasional pain, and 4% had daily pain. Comparison of the injured and uninjured elbows demonstrated a 3 degrees reduction of flexion (P <.05) and a 5 degrees loss of extension (P <.01). More than 50% of the fractured elbows had degenerative changes (joint space narrowing, subchondral cysts, subchondral sclerosis, and osteophytes) (P <.001), and 4 had osteoarthritis (P <.05). No subjective, objective, or radiographic differences were found when the two techniques were compared. Removal of the hardware was performed in 81% of the patients with tension-band wiring and in 43% of the patients with figure-of-eight wiring (P <.01). The figure-of-eight technique can, therefore, be recommended, as it is associated with less frequent secondary procedures for hardware removal.  相似文献   
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Patients attending the emergency room with acute asthma, participating in a study comparing salbutamol (albuterol in the United States) via a dry powder inhaler (Turbuhaler®) with pressurized metered-dose inhaler (pMDI), were included in this 1-week follow-up study with the aim of assessing whether inhaled budesonide via Turbuhaler may be an alternative to prednisolone tablets after an acute asthma attack. Eighty-one patients with a mean age of 38 years and forced expiratory volume in 1 sec (FEV1) of 64% predicted normal value after treatment with salbutamol were randomized in this double-blind, double-dummy, parallel-group study. The doses given were budesonide 1600 μg b.i.d. or prednisolone in daily doses from 40 mg (day 1) decreased to 5 mg (day 7). FEV1 was recorded before and after the 7-day treatments and peak expiratory flow (PEF) morning and evening, clinical symptoms (visual analogue scale 0-100), and doses of rescue medication (terbutalineTurbuhaler 0.25 mg/dose) were recorded daily. The mean increase in FEV, from baseline to day 7 was 1 7.3% in the budesonide Turbuhaler group and 1 7.6% in the prednisolone group. Mean values of morning PEF increased from day 1 to day 7 by 67 L/min in the budesonide Turbuhaler group and by 57 L/min in the prednisolone group (not significant). There were no statistically significant differences between the groups in clinical symptoms and in the number of doses of rescue medication. Because of disease deterioration, five patients in the Turbuhaler group and three in the prednisolone group needed additional symptomatic as well as corticosteroid treatment. Inhaled budesonide in high doses may be a substitute for oral therapy as follow-up treatment after an acute asthma attack.  相似文献   
108.
Summary In order to explain the higher prevalence of fractures in urban compared with rural areas, 782 residents in the city of Malmö, Sweden and 486 inhabitants from the nearby rural municipality of Sjöbo were invited to participate in an sex- and age-matched cross-sectional study on life-style differences; 73 and 80% respectively responded. Responders answered a questionnaire on medical and social background and were interviewed on past and present physical activity. The men and women of the rural area were found to be significantly more active physically at work and during spare time. Housing was larger in the rural area. For women, these differences are decreasing in the younger age groups. Bone mass was found to be correlated to heavier work load for men. Other life-style variable such as dairy calcium intake, coffee drinking, estrogen medication, and morbidity, could not explain this difference. Higher prevalence of fractures in the city could therefore be explained by physicall less active life-style.  相似文献   
109.
To find the maximal depth of an ectatic vessel in the dermis that contributes to the abnormal color of a port wine stain (PWS), “normal” and “laser treated PWS skin” are modeled, respectively, as a two-layer plane parallel geometry consisting of an epidermis and a dermis, and as a three-layer geometry consisting of an epidermis, a dermis without additional blood (the “treated” part of the stain, assumed identical to the “normal” dermis), and a layer of dermis containing 5% or 10% of blood per volume (the untreated part of the PWS). Spectral remittances were calculated for various wavelengths using the diffusion approximation to the transport equation for light propagation. These remittances were transformed into the CIE 1976 (L*a*b*)-color system. Color differences between “normal” and PWS skin as a function of the dermal depth of “injured” ectatic blood vessels were calculated. The maximal depth where ectatic blood vessels just contribute to the abnormal PWS color is predicted as 0.9 mm for a “normally” pigmented epidermis (60 μm thick) and a 5% or 10% blood per volume content. For a darker pigmented epidermis (60 μm thickness) and again at both 5% and 10% blood per volume content, this depth was found to be 0.8 mm. © 1993 Wiley-Liss, Inc.  相似文献   
110.
Specimens from the ovarian cortical stroma of 15 postmenopausal women were examined histologically and were incubated for 4 hours in Krebs' bicarbonate buffer containing 5.5 mM glucose and 1% bovine serum albumin. Specimens of normal postmenopausal stroma produced measurable amounts of androstenedione, estradiol, and progesterone in vitro. Specimens with stromal hyperplasia produced larger amounts of androstenedione and estradiol than those with normal stroma. Androstenedione was the predominant steroid produced in both groups. The nonnegligible formation of estradiol indicated an aromatizing capacity of the stromal tissue. The addition of hCG elicited a significant increase in cyclic AMP formation in specimens from ovaries with stromal hyperplasia, indicating a preserved responsiveness to gonadotropin in this type of ovaries.  相似文献   
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