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1.
The treatment of Legg-Calvé-Perthes disease remains controversial. The aim of this survey was to ascertain the current management strategies of this condition amongst UK paediatric orthopaedic surgeons, with particular regard to containment procedures in the fragmentation phase. Questionnaires were distributed at the January 2006 meeting of the British Society for Children’s Orthopaedic Surgery (BSCOS) and was posted to all absent members. The results showed a great deal of variability not only in the treatment of Perthes disease, but also in the decision-making processes. Consideration must now be given to a carefully constructed national multi-centre prospective randomised controlled study into the optimum management of this disease  相似文献   
2.
Annamalai P  Rao AL 《Virology》2005,338(1):96-111
To begin elucidation of the relationship between Brome mosaic virus (BMV) replication and encapsidation, we used a T-DNA-based Agrobacterium-mediated transient expression (agroinfiltration) system in Nicotiana benthamiana leaves to express either individual or desired pairs of the three genomic RNAs. The packaging competence of these RNAs into virions formed by the transiently expressed coat protein (CP) was analyzed. We found that in the absence of a functional replicase, assembled virions contained non-replicating viral RNAs (RNA1 or RNA2 or RNA3 or RNA1 + RNA3 or RNA2 + RNA3) as well as cellular RNAs. By contrast, virions assembled in the presence of a functional replicase contained only viral RNAs. To further elucidate the specificity exhibited by the functional viral replicase in RNA packaging, replication-defective RNA1 and RNA2 were constructed by deleting the 3' tRNA-like structure (3' TLS). Co-expression of TLS-less RNA1 and RNA2 with wt RNA3 resulted in efficient synthesis of subgenomic RNA4. Virions recovered from leaves co-expressing TLS-less RNA1 and RNA2 and either CP mRNA or wt RNA3 exclusively contained viral RNAs. These results demonstrated that packaging of BMV genomic RNAs is not replication dependent whereas expression of a functional viral replicase plays an active role in increasing specificity of RNA packaging.  相似文献   
3.
We measured cytokine secretion patterns in peripheral blood and granulation tissue by flow cytometry in 16 human immunodeficiency virus (HIV) positive and 26 HIV negative patients with spinal tuberculosis. Anti-retroviral therapy was not prescribed. There were no significant differences in the postoperative morbidity and neurological recovery between the two groups.
Résumé Nous avons mesuré, par cytométrie en flux, la sécrétion de cytokine dans le sang périphérique et le tissu de granulation chez des patients atteints de tuberculose rachidienne, 16 HIV positifs et 26 HIV négatifs. Il n’y avait pas de différence significative dans la morbidité post-opératoire et la récupération neurologique entre les deux groupes.


Accepted: 21 February 2000  相似文献   
4.
5.
A 12- week feeding trial was conducted to determine the effects of dietary vitamin C levels on the growth performance, antioxidant ability, muscle composition and enzyme activity in freshwater prawn, Macrobrachium rosenbergii. The experimental basal diets were supplemented with M. rosenbergii at the rates of 0 (control), 25, 50, 75, 150 and 300 mg/kg dry feed weight and the assays were in triplicate. Growth performance, body composition, antioxidant activity and serum biochemistry parameters were determined. However, the present investigation revealed that prawns fed with diet supplemented with 25–150 mg/kg of vitamins C shows enhanced (P < 0.05) growth performance, including final weight and weight gain. Additionally, prawns fed with 25–150 mg/kg of vitamins C supplemented diets achieved significant (P < 0.05) improvement in growth performance, digestive enzyme activities, and muscle biochemical composition, while, the prawns fed with 150 mg/kg of vitamin C showed enhanced performance respectively. However, the prawns fed with above 150–300 mg/kg showed poor performance. The antioxidant enzymatic activity (SOD, CAT) metabolic enzyme status in muscle showed no significant (P > 0.05) alterations in prawns fed with 25–150 mg/kg of vitamin C supplemented diets. Therefore, the present findings suggested that 150 mg/kg of vitamin C could be supplemented for flexible enhanced survival, growth, antioxidant defense system and production of M. rosenbergii.  相似文献   
6.

Background

Myocarditis complicated by cardiogenic shock remains a complex problem. The use of acute mechanical circulatory support devices for cardiogenic shock is growing. We explored the utility of Impella transvalvular microaxial flow catheters in the setting of myocarditis with cardiogenic shock.

Methods and Results

We retrospectively analyzed data from 21 sites within the cVAD registry, an ongoing multicenter voluntary registry at sites in North America and Europe that have used Impella in patients with myocarditis. Myocarditis was defined by endomyocardial biopsy (n?=?11) or by clinical history without angiographic evidence of coronary disease (n?=?23). A total of 34 patients received an Impella 2.5, CP, 5.0, or RP device for cardiogenic shock complicating myocarditis. Baseline characteristics included age 42 ± 17 years, left ventricular ejection fraction (LVEF) 18% ± 10%, cardiac index 1.82 ± 0.46 L·min?1·m?2, pulmonary capillary wedge pressure 25 ± 7 mm Hg, and lactate 27 ± 31 mg/dL. Before Impella placement, 32% (n?=?11) of patients required intra-aortic balloon pump. Mean duration of Impella support was 91 ± 74 hours; 21 of 34 patients (62%) survived the index hospitalization and were discharged with an improved mean LVEF of 37.32% ± 20.31% (P?=?.001); 15 patients recovered with successful support, 5 patients were transferred to another hospital on initial Impella support, 1 patient underwent orthotopic heart transplantation. Ten patients required transition to another mechanical circulatory support device.

Conclusions

This is the largest analysis of Impella-supported myocarditis cases to date. The use of Impella appears to be safe and effective in the settings of myocarditis complicated by cardiogenic shock.  相似文献   
7.
8.
BackgroundDeep venous thrombosis (DVT) occurs in 0.1% of persons per year, affecting 15%–40% of general surgical procedures without prophylaxis. Thromboembolic prophylaxis is not commonly used after orthotopic liver transplantation (LT) owing to the risks of bleeding and coagulopathy. Cirrhosis and the association with the coagulation cascade, before and after transplantation, are not well understood. The purpose of this study was to determine the incidence of DVT and its risk factors after LT.MethodsWe retrospectively reviewed LTs performed at our center from 2005 to 2012. We identified patients with Doppler examinations showing DVT after LT, platelet count, and international normalized ratio (INR) at time of DVT, associated symptoms, DVT prophylaxis, and perioperative risk factors. We determined the incidence of DVT, the odds ratio of each preoperative risk factor, the difference in platelet count and INR between those with and without a DVT, and the weighted risk of each factor in the development of DVT with the use of logistic regression modeling.ResultsOf 314 patients, the incidence of DVT was 8.6% (27/314). Between those with and without DVT there was no significant difference in age, sex, platelet count, INR, infection, hepatocellular cancer, use of venous bypass, and prior surgery. There was a significant difference in mobility, 67% vs 20% (P < .0001), and the use of factor VII, 11% vs 2% (P < .05). The estimated risk for of developing DVT for patients with neither of these factors was 4%; with factor VII the risk rose to 17%; with mobility difficulty the risk rose to 23%; and with both the risk was 62%. In our entire population, there were no cases of pulmonary embolism.ConclusionsThe risk of developing a DVT after LT is ≥9% even with mechanical DVT prophylaxis. Consideration should be given to using both mechanical and chemical prophylaxis after LT.  相似文献   
9.
Tungsten heavy alloys are two-phase metal matrix composites that include W–Ni–Fe and W–Ni–Cu. The significant feature of these alloys is their ability to acquire both strength and ductility. In order to improve the mechanical properties of the basic alloy and to limit or avoid the need for post-processing techniques, other elements are doped with the alloy and performance studies are carried out. This work focuses on the developments through the years in improving the performance of the classical tungsten heavy alloy of W–Ni–Fe through doping of other elements. The influence of the percentage addition of rare earth elements of yttrium, lanthanum, and their oxides and refractory metals such as rhenium, tantalum, and molybdenum on the mechanical properties of the heavy alloy is critically analyzed. Based on the microstructural and property evaluation, the effects of adding the elements at various proportions are discussed. The addition of molybdenum and rhenium to the heavy alloy gives good strength and ductility. The oxides of yttrium, when added in a small quantity, help to reduce the tungsten’s grain size and obtain good tensile and compressive strengths at high temperatures.  相似文献   
10.
Salivary gland tumors are uncommon and constitute about 2.0 to 6.5 % of all head and neck tumors. Incidence of basal cell adenoma is about 1 to 3 % of salivary gland tumors. We present a rare case of basal cell adenoma of the parotid and a review of literature.  相似文献   
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