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1.
The management of three patients with left ventricular fibromas is outlined. All were asymptomatic children. Routine chest radiography suggested cardiac masses. M-mode and two-dimensional echocardiography were valuable adjuncts to conventional angiography in assessing these children. Electrocardiographic changes, present in all cases, were shown to regress postoperatively. We stress the importance of these noninvasive aids in the initial investigation and outline our operative methods of reconstruction.  相似文献   
2.
个体化下肢小腿假肢接受腔设计的生物力学评价技术研究   总被引:3,自引:0,他引:3  
作为传递体重、固定假肢的部件 ,接受腔对于小腿假肢使用的舒适性和方便程度有决定性的作用。本研究建立了基于有限元应力分析的小腿假肢生物力学评价技术平台 ,实现了小腿残端 /接受腔 3D几何建模与信息交互、三维有限元自动建模及应力分析。 3D模型与信息交互的实现基于得到广泛支持的OpenGL技术 ,有限元模型的构建采用了专门针对小腿残端 /接受腔结构特点的自动建模方法 ,通过构建档案数据库系统作为整个系统的操作平台。该技术平台可与现有的CAD/CAM系统相结合 ,为接受腔的个体化设计提供生物力学定量化依据。其临床应用将改善传统的设计流程 ,提高设计效率。同时 ,它也是未来构建接受腔设计专家 /智能系统的基础。  相似文献   
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Lung carcinoma remains one of the most frequent and aggressive human neoplasms. Fortunately, in the last decades, the increasing knowledge of the molecular mechanisms leading to cancer development has allowed the use of targeted therapies with improvement of prognosis in many patients. Clinical management has also changed after the introduction of endobronchialultrasonographic bronchoscopy that allows a conservative staging of lung tumors, avoiding the need of mediastinoscopy for lymph node staging. Lung pathologists and cytopathologists are facing the challenge of giving the more comprehensive prognostic and predictive information with ever smaller tissue or cytological samples. The aim of this review is to summarize the molecular testing for non-small cell lung carcinoma and how pathologists can contribute to the patient's outcome with a conscious management of biological samples.  相似文献   
5.
碱离子水饮用后血小板聚集率的的变化(附30例报告)   总被引:1,自引:0,他引:1  
目的:报告30例饮用豪斯牌碱离子水前、后血小板聚集率的变化。方法:饮用碱离子水前、后(2~3月,>3~6月)作比浊法血小板聚集试验,以1分钟、5分钟及5分钟内最大聚集率(Max%)为指标,同时检测部分血粘度指标及凝血因子,并用自动生化仪检测血糖、血脂、主要电解质及部分肝、肾功能。结果:饮碱离子水后,血小板聚集率明显下降,而以疾病组(Max>80%)下降尤为明显,P均<0.001。饮碱离子水后血小板聚集率的下降,部分可能与损伤的血管内皮得到修复有关。主要电解质及部分肝、肾功能无明显异常改变。结论:由于心、脑血管血栓性疾病患者血小板聚集率多明显升高,饮碱离子水后血小板聚集率明显下降,且长期饮用对主要电解质及部分肝、肾功能无明显异常改变,作者认为碱离子水使用方例、安全、有效、价廉,因而对心、脑血管血栓性疾病防治方面可能是一种积极的辅助方法,值得临床进一步探索。  相似文献   
6.
PURPOSE: Ureteral dysfunction is a significant sequela of congenital bladder outlet obstruction. However, the structural and functional alterations associated with ureteral dysfunction are not well defined. A model of fetal bladder obstruction in sheep was used to characterize the changes in ureteral smooth muscle, extracellular matrix (ECM) and functional properties in response to bladder outlet obstruction. MATERIALS AND METHODS: Partial bladder outlet obstruction was created in fetal sheep at gestational age 95 days via placement of a metal ring around the proximal urethra as well as ligation of the urachus. Ureters were harvested at 109 and 135 days (full term = 140 days) to determine the relative composition of smooth muscle, ECM and urothelium by morphometric analysis and to measure DNA and protein concentrations. Ureteral tissue from 135 day gestation obstructed and control sheep was harvested and immediately placed in Krebs solution. Smooth muscle strips (2-3 mm. x 7-8 mm.) were suspended in organ baths. The frequency and amplitude of spontaneous ureteral contractions was as well as the response to electric field stimulation (EFS) were determined. RESULTS: Bladder outlet obstruction caused a significant increase in ureteral weight, smooth muscle mass and total ECM at both 109 and 135 days gestation. Total ureteral DNA was greater in obstructed compared with sham ureters at 135 days gestation. Obstructed ureters demonstrated greater amplitude and frequency of spontaneous contractions as well as more pronounced response to EFS when compared to sham ureters. CONCLUSIONS: The fetal ureter responds to bladder obstruction with smooth muscle hyperplasia and hypertrophy which is associated with increased spontaneous activity and augmented response to EFS. ECM content is markedly increased indicating a shift in the balance of connective tissue synthesis and degradation. Congenital post-obstructive ureteral dysfunction therefore appears to be the result of dysregulated smooth muscle cell growth and altered ECM homeostasis producing abnormal ureteral contractility.  相似文献   
7.
In this study is reviewed the experience at Papworth Hospital, Cambridgeshire, and Great Ormond Street Hospital, London, with combined heart-lung transplantation. Between April 1984 and June 1989, 73 patients have undergone heart-lung transplantation. Donors and recipients were carefully matched with regards to serology, morphology and cytomegalovirus compatibility. Heart preservation was based on use of cold St. Thomas' cardioplegic solution; a pulmonary preservation fluid has been developed that allows distant organ procurement with a single pulmonary artery flush technique (Papworth solution). The recipients were: 21 pts with Eisenmenger's syndrome, 15 pts with pulmonary hypertension, 37 pts with pulmonary disease (including 22 cystic fibrosis). The results are: no surgical mortality; no acute cardiac rejection episodes. Twenty-three patients died (16 with infections, 3 with obliterative bronchiolitis, 2 with cerebral embolism and 2 others). The actuarial survival rate at one year is 73.2%; 63% at two years and 47.4% at four years. The use of transbronchial biopsy of the lung has provided accurate early and safe diagnosis of pulmonary rejection. Development in organ preservation and patient management, as well as careful selection of recipients and donors, have led to the effective use of resources and thereby to these good results.  相似文献   
8.
Due to the COVID-19 pandemic most oral and maxillofacial surgical (OMFS) units have moved to conducting patient consultations over the telephone. The aim of this study was to assess patients' satisfaction with telephone consultations during the COVID-19 pandemic. A retrospective survey was conducted of OMFS patients at our hospital who had telephone consultations between 1 April - 8 June 2020. The survey was conducted by independent interviewers and used the Generic Medical Interview Satisfaction Scale (G-MISS) along with a previously published additional questionnaire. Variables recorded included age, gender, theme of consultation, grade of clinician, and type of consultation. Statistical analysis was performed to assess for any differences between patient groups. The records of 150 consecutive patients were reviewed and 135 met inclusion criteria. A total of 109 patients completed the survey giving a response rate of 80.74%. The total G-MISS score for satisfaction was high, which indicates a high level of satisfaction among all patients. We found no statistical difference in satisfaction when comparing patients in terms of gender, age, theme of consultation, or level of clinician. A significant difference was found in compliance levels between review and new patients, with review patients demonstrating higher compliance levels (p=0.004). Overall, 83.48% of patients said they would be willing to have a telephone consultation in future. The majority of patients in this study reported high levels of satisfaction with telephone consultations. New patients reported lower levels of compliance which may suggest this type of consultation is less suited to telephone consultation.  相似文献   
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Benzodiazepines are allosteric agonists of GABAA receptors (GABAAR), pentameric ligand‐gated Cl? channels, which serve both an important neurodevelopmental role but are also the principal inhibitory system in the brain. However, their subunit composition, channel properties, and function, as well as their region‐specific expression patterns, change through development. These processes have been extensively studied in rodents and to some extent confirmed in higher species. Specifically, GABAARs acquire faster kinetics with age and their pharmacology changes rendering them more sensitive to drugs that have higher affinity for α1 subunit‐containing GABAARs, such as benzodiazepines, but also, their inhibitory function becomes more potent as they shift from having depolarising to hyperpolarising responses due to a shift in Cl? gradient and cation chloride cotransporter expression. Concerns have been raised about possible pro‐apoptotic and paradoxical effects of benzodiazepines in the neonatal normal rat brain, although it is unclear, as yet, whether this extends to brains exposed to seizures. Growing evidence indicates that the pharmacology and physiology of GABAARs may be altered in the brain of rats or humans with seizures or epilepsy, or different aetiologies that predispose to epilepsy. These changes follow different paths, depending on sex, age, region, cell type, aetiology, or time‐point specific factors. Identification of dynamic biomarkers that could enable these changes in vivo to be monitored would greatly facilitate the selection of more effective agonists with fewer side effects.  相似文献   
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