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1.
Background : Malnutrition is very frequent in childhood cancer. Its main cause is inadequate intake for energy demands owing to lack of appetite. Megestrol acetate is a synthetic progestin that has been used for reversing anorexia in adult cancer.
Objectives : To assess megestrol acetate efficacy and side-effects in treating anorexia in childhood cancer.
Methods : Thirty-five children with solid tumours were receiving antitumour therapy. Nutritional assessment was by anthropometry. Megestrol acetate efficacy was assessed by evaluating grade of appetite, energy intake and well-being. Side-effects were evaluated by means of clinical history, physical examination, lipid profile, coagulation tests and cortisol rhythm.
Results : When compared to baseline all the anthropometric measurements increased ( P <0.05) from the first month of megestrol acetate therapy, as well as appetite and energy intake. No significant side-effects were found.
Conclusion : Megestrol acetate therapy is a powerful appetite stimulant which led to weight gain, composed of both fat mass and fat-free mass. Megestrol acetate is well tolerated, with few and mild side-effects. If megestrol acetate therapy is started at the onset of anorexia, the use of more expensive, invasive and complicated techniques of nutritional support may be avoided.  相似文献   
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Echinococcal infection of the heart is rare. The preoperativefindings, with special attention to two-dimensional echocardiography(2DE), of six patients with cardiac echinococcosis and theirsurgical and pathological correlations are reported. Cardiachydatid cysts (HCs) were located in the cardiac apex in threepatients, in the upper part of the interventricular septum extendingtowards the anterior aspect of the heart in one and in the postero-superiorright atrial wall in another patient. The remaining patienthad multiple intrapericardial cysts. In three patients the cystspresented as well defined, rounded, echolucent masses withinthe myocardial wall bulging into the cardiac chambers. In twopatients, the cysts had ruptured into a cardiac chamber withloss of the characteristic ‘cystic’ appearance;these cysts presented as an echogenic or solid mass protrudinginto a cardiac chamber. Finally, another patient had one HCwith echolucent appearance and another HC in a different locationwith echogenic appearance; this last cyst corresponded to adegenerated HC. In two cases the cyst showed a loculated internalaspect. In one patient the myocardial segment involved by thecyst had a dyskinetic movement. In all six patients, 2DE accuratelydemonstrated the location and morphological details of the cardiaccysts, permitted recognition of the ruptured and/or degeneratedcysts and was superior to thoracic computed tomography and angiographyin the preoperative assessment of these patients. Nuclear magneticresonance imaging (one patient) gave no further informationto that obtained by 2DE. We conclude that 2DE is the techniqueof choice for an early diagnosis of this rare entity.  相似文献   
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Objective

To compare the static frictional forces generated at the bracket/wire interface of stainless steel brackets with different geometries and angulations, combined with orthodontic wires of different diameters.

Material and Methods

The frictional forces were evaluated with three different types of metal brackets: a passive self-ligating (SmartClipTM, 3M/Unitek, Monrovia, USA), with a modified slot design (Mini Uni TwinTM, 3M/Unitek, Monrovia, USA) and conventional (Kirium, Abzil, São José do Rio Preto, Brazil). The samples were mounted in a testing device with three different angulations and tested with 0.014" and 0.018" stainless steel wires (American Orthodontics, Sheboygan, USA). The static frictional force was measured using a universal testing machine (DL 500, EMIC®, São José dos Pinhais, Brazil) with a crosshead speed of 1 mm/min. Statistical analysis was performed by two-way ANOVA followed by Bonferroni''s post hoc test.

Results

There was a significant difference (p<0.05) in static friction when the three types of brackets were tested with the same wire size. The wire diameter influenced friction only when the brackets had a 10º angulation (p<0.05). The angulation influenced friction (p<0.05) when the brackets were associated with a 0.018" wire.

Conclusion

Brackets with a modified slot design showed intermediate static frictional force values between the conventional and self-ligating brackets tested.  相似文献   
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In São Paulo City, Brazil, 121 patients with moderatelysevere envenoming by Bothrops snakes (principally B. jararaca)were randomized for treatment with Brazilian polyspecific Bothropsantivenoms: Instituto Butantan (39 patients), Instituto VitalBrazil (41), Fundação Ezequiel Dias (FUNED) (41).The initial dose was four ampoules (40 ml) in 89 patients withless severe envenoming and eight ampoules (80 ml) in 32 patientswith more severe envenoming. A second dose of four ampouleswas required in 20 patients. Patients receiving the three antivenoms were comparable in allrespects before treatment There were no deaths. The majorityshowed rapid clinical improvement, resolution of local envenoming,cessation of bleeding and restoration of blood coagulability.No differences in the efficacy of the three antivenoms wererevealed by clinical or laboratory observations, including measuresof haematological, haemostatic and biochemical ab normalities.Twelve patients developed abscesses (Butantan 1, Vital Brazil6, FUNED 5) and seven developed local necrosis (3,1,3). Of 88patients followed up 20–30 days after the bite 33 (37.5%)still had symptoms or signs of local envenoming, especiallyswelling. Early (anaphylactic) reactions were unexpectedly frequent afterall three antivenoms but were significantly more frequent withButantan (87%) than with Vital Brazil (37%) or FUNED (56%) antivenoms(p < 0.001). A possible explanation was the higher totalprotein content and percentage immunoglobulin of Butantan antivenom. The doses of antivenom recommended in Brazil and used in thisstudy may be unnecessarily high, resulting in an unacceptablyhigh incidence of reactions. Results of the study should prompta critical re-evaluation of antivenom production techniquesand dosage recommendations in Brazil.  相似文献   
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A 58-year-old woman presented with a new rapidly progressive lesion distal to a stent. This lesion was treated with atherectomy through the stem in order to characterize it pathologically. The aggressive proliferative response discovered suggested that this unusually distal lesion was produced by the trauma of her previous angioplasty .  相似文献   
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