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21.
Given the increasing advocacy for the use of inhaled corticosteroids as a treatment of choice for persistent asthma, growing numbers of children are being exposed to the possible growth-suppressing effects of glucocorticoids. Recent evidence strongly suggests that, when consistently administered at moderate doses, inhaled corticosteroids (IC) are capable of slowing growth in children. Whether such growth suppression would persist and ultimately affect final adult height remains unknown. Therapeutic goals which aim for uninterrupted inflammatory disease control rather than periodic symptom control may increase the occurrence of growth failure in children treated with IC. In this article, current information about the mechanisms of growth suppression by glucocorticoids and the effects of IC on growth is reviewed, and recommendations for designing studies to investigate the effects of drugs on growth are presented.  相似文献   
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The variation in colorectal cancer (CRC) incidence worldwide strongly suggests a role for dietary influences. Based on epidemiological data, protective effects of vegetables and fruit intake on CRC are widely claimed, while other data indicate a possible increased CRC risk from (higher) dietary fat intake. Therefore, we have investigated single and interactive effects of dietary fat and a vegetable-fruit mixture (VFM) in the ApcMin mouse, a mouse model for multiple intestinal neoplasia. In this study, four different diets (A-D) were compared, which were either low in fat (20% energy diets A/B) or high in fat (40% energy diets C/D). In addition, 19.5% (wt/wt) of the carbohydrates in diets B and D were replaced by a freeze-dried VFM. The diets were balanced so that they only differed among each other in fat/carbohydrate content and the presence of specific plant-constituents. Because the initiation of intestinal tumors in ApcMin mice occurs relatively early in life, exposure to the diets was started in utero. Without the addition of VFM, mice maintained at a high-fat diet did not develop significantly higher numbers of small or large intestinal adenomas than mice maintained at a low-fat diet. VFM added to a low-fat diet significantly lowered multiplicity of small intestinal polyps (from 16.2 to 10.2/mouse, 15 animals/group), but not of colon tumors in male ApcMin mice only. Strikingly, addition of VFM to female mice maintained on a low-fat diet and to both sexes maintained on a high-fat diet significantly enhanced intestinal polyp multiplicity (from 16.5 to 26.7 polyps/mouse). In conclusion, our results indicate that neither a lower fat intake nor consumption of VFM included in a high-fat diet decreases the development of polyps in mice genetically predisposed to intestinal tumor development.   相似文献   
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BACKGROUND: Mitral valve disease is often accompanied by atrial fibrillation, which may compromise the patient even after the valvular lesion has been repaired. METHODS: Three patients with rheumatic type mitral valve disease and chronic atrial fibrillation were treated by mitral valve replacement with cryopreserved mitral valve homograft and Maze III procedure, as a method to relieve both the valvular pathology and the rhythm disorder. The patients' clinical courses have been followed for up to 1 year after operation. RESULTS: All patients survived operation, and all have normal sinus rhythm. None are taking cardiac medications. CONCLUSIONS: Long-term treatment with warfarin should not be required, and other cardiac medicines may be eliminated following mitral valve replacement with homograft combined with Maze III procedure.  相似文献   
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Stoll  D; Cines  DB; Aster  RH; Murphy  S 《Blood》1985,65(3):584-588
We studied ten normal subjects and 20 patients with stable, untreated idiopathic thrombocytopenic purpura (ITP) and platelet counts in the range of 35,000 to 110,000/microL. The diagnosis was made by clinical criteria. Platelet-associated IgG was increased in all nine of the nine patients studied. Autologous platelets were labeled with chromium 51 and reinfused for measurement of mean cell life and platelet production rate. Mean cell life was calculated by two methods, weighted mean and multiple hit, with excellent agreement between the two. As expected, mean cell life was significantly reduced in ITP patients as compared to the normal subjects (2.9 days v. 8.0 days, P less than .001). However, mean platelet production rates in ITP patients and normal subjects, 3.5 and 3.8 X 10(9) platelets/k/d respectively, were not significantly different. Platelet production rate was above and below the normal range (2 to 5.6 X 10(9) platelets/k/d) in two and four patients, respectively. We conclude that the rate of platelet production is not increased in most patients with ITP who have platelet counts greater than 35,000/microL. We did find that platelet size was increased in eight of the 12 patients in whom it was measured, including two of the patients with low platelet production.  相似文献   
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Characterization of the histone core complex.   总被引:3,自引:0,他引:3       下载免费PDF全文
A stable histone core complex containing equimolar ratios of H2A, H2B, H3, and H4 has been isolated from chicken erythrocyte chromatin in high salt. This complex has been characterized by sedimentation and chemical cross-linking studies. In velocity ultracentrifugation, only one single sharp sedimentation boundary has been observed with sedimentation coefficient S020,w = 3.8 +/- 0.1. The molecular weight of the histone core complex has been investigated by low-speed sedimentation equilibrium studies over a wide range of protein concentration. Analysis of the apparent weight-average molecular weight as a function of concentration indicates that the histone core complex in 2 M NaCl, pH 9.0, is in equilibrium between a tetramer (H2A)(H2B)(H3)(H4) and an octamer [(H2A)(H2B)(H3)(H4)]2 species with a tetramer molecular weight of 55,000. The equilibrium constant K is approximately 1.2 X 10(-5) liter per mol at 10 degrees. Evidence of such a tetramer-octamer equilibrium in solution is also supported by the results of our chemical crosslinking experiments on the histone core complex.  相似文献   
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An increased incidence of monkeypox (MPX) infections in the Democratic Republic of the Congo was noted by the regional surveillance system in October 2013. Little information exists regarding how MPX is introduced into the community and the factors associated with transmission within the household. Sixty-eight wild animals were collected and tested for Orthopoxvirus. Two of three rope squirrels (Funisciurus sp.) were positive for antibodies to Orthopoxviruses; however, no increased risk was associated with the consumption or preparation of rope squirrels. A retrospective cohort investigation and a case–control investigation were performed to identify risk factors affecting the introduction of monkeypox virus (MPXV) into the community and transmission within the home. School-age males were the individuals most frequently identified as the first person infected in the household and were the group most frequently affected overall. Risk factors of acquiring MPXV in a household included sleeping in the same room or bed, or using the same plate or cup as the primary case. There was no significant risk associated with eating or processing of wild animals. Activities associated with an increased risk of MPXV transmission all have potential for virus exposure to the mucosa.  相似文献   
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