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71.
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《European journal of medical genetics》2023,66(1):104673
Heritable thoracic aortic diseases (HTAD) are rare pathologies associated with thoracic aortic aneurysms and dissection, which can be syndromic or non-syndromic. They may result from genetic defects. Associated genes identified to date are classified into those encoding components of the (a) extracellular matrix (b) TGFβ pathway and (c) smooth muscle contractile mechanism. Timely diagnosis allows for prompt aortic surveillance and prophylactic surgery, hence improving life expectancy and reducing maternal complications as well as providing reassurance to family members when a diagnosis is ruled out. This document is an expert opinion reflecting strategies put forward by medical experts and patient representatives involved in the HTAD Rare Disease Working Group of VASCERN. It aims to provide a patient pathway that improves patient care by diminishing time to diagnosis, facilitating the establishment of a correct diagnosis using molecular genetics when possible, excluding the diagnosis in unaffected persons through appropriate family screening and avoiding overuse of resources. It is being recommended that patients are referred to an expert centre for further evaluation if they meet at least one of the following criteria: (1) thoracic aortic dissection (<70 years if hypertensive; all ages if non-hypertensive), (2) thoracic aortic aneurysm (all adults with Z score >3.5 or 2.5–3.5 if non-hypertensive or hypertensive and <60 years; all children with Z score >3), (3) family history of HTAD with/without a pathogenic variant in a gene linked to HTAD, (4) ectopia lentis without other obvious explanation and (5) a systemic score of >5 in adults and >3 in children. Aortic imaging primarily relies on transthoracic echocardiography with magnetic resonance imaging or computed tomography as needed. Genetic testing should be considered in those with a high suspicion of underlying genetic aortopathy. Though panels vary among centers, for patients with thoracic aortic aneurysm or dissection or systemic features these should include genes with a definitive or strong association to HTAD. Genetic cascade screening and serial aortic imaging should be considered for family screening and follow-up. In conclusion, the implementation of these strategies should help standardise the diagnostic work-up and follow-up of patients with suspected HTAD and the screening of their relatives. 相似文献
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Federico G. Usuelli Cristian Indino Alberto Leardini Luigi Manzi Maurizio Ortolani Paolo Caravaggi 《Foot and Ankle Surgery》2021,27(2):150-155
BackgroundIn severe cases of ankle and subtalar arthritis, arthrodesis of the subtalar joint is performed in combination with ankle arthroplasty. In these special cases gait analysis reveals real motion at the replaced tibiotalar joint.MethodsTwenty-three patients affected by ankle and subtalar arthritis, treated either with a 3-component or a 2-component prosthesis in combination with subtalar arthrodesis, were clinically evaluated preoperatively and at a minimum of 1-year follow-up. Gait analysis was performed postoperatively using a multi-segment foot protocol. Foot kinematics were compared to corresponding data from a healthy control group.ResultsClinical scores significantly improved from preoperative to follow-up. The clinically measured passive ankle dorsiflexion/plantarflexion significantly improved at the follow-up. Patients’ normalized walking speed and stride length were significantly lower than those in control. With exception of the ankle frontal-plane motion, sagittal-plane mobility of foot joints was about 50% than that in healthy joints.ConclusionsImprovement in clinical scores was found for both prostheses. Normal spatio-temporal parameters were not restored. In these patients, fusion of the subtalar joint appeared to be compensated by larger frontal-plane motion at the tibiotalar joint.Level of evidenceLevel III- retrospective comparative study.The study was approved by the local Ethics Committee as protocol MAT (protocol registration at clinicaltrials.gov NCT03356951). 相似文献
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GK型机械瓣空化可视化研究 总被引:1,自引:0,他引:1
对国产GK27型机械二尖瓣进行了单次关闭方式的离体空化实验,采用数码相机拍摄了空泡照片。机械瓣阻塞体关闭后,云状空泡出现在挡座周围,呈放射状向外运动,空化原因是机械瓣关闭时阻塞体与挡座的撞击形成的局部挤压射流,挤压缝隙出口射流速度高达9m/s,局部低压造成空化,在机理上,这是附壁射流引起的旋涡空化。关闭速度是衡量机械瓣空化趋势的重要指标之一。空化历时随心室载荷率的增加而增加,在载荷率为2750mmHg/s时,最大空化历时达440μs。机械瓣空化临界载荷率为420mmHg/s,这比动物实验所得的正常生理条件750mmHg/s低,因此在人体正常生理条件下,机械二尖瓣存在空化的可能。 相似文献
78.
Khai Lai Monica Rencken Barbara L. Drinkwater Charles H. Chesnut III 《Calcified tissue international》1993,53(4):225-228
Summary The purpose of this study was to determine whether bone mineral density (BMD) measurements at the lumbar spine and femoral neck provided comparable information to women planning to use that knowledge to help them make a decision about hormone replacement therapy. Eighty-eight healthy Caucasian women, aged 44–59 and within 0 to 5 years of menopause, participated in the study. BMD measurements were performed at the lumbar spine (L1-L4) and the femoral neck by dual energy X-ray absorptiometry (DXA). Criteria suggested by the National Osteoporosis Foundation were used to categorize women as at risk for osteoporosis, bone density more than one standard deviation (SD) below the young adult mean, or as low risk, bone density at or above this level. The re that 46 women would be classified into the low risk category on the basis of spinal BMD alone. However, 28 of these 46 women would fall into the at risk category when the femoral neck BMD was measured. Sixty-one percent of women informed they were at low risk on the basis of spinal BMD would be considered at risk based on femoral neck BMD. When femoral neck BMD was used as the primary risk indicator, 14% of the women classified as low risk would be at risk if spinal BMD were added. These results suggest that both lumbar spine and proximal femur measurements should be made when women are using bone density measurements as an aid in deciding whether or not to use hormone therapy in their postmenopausal years. 相似文献
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B. Skruodies J. V. Wening Prof. Dr. K. H. Jungbluth 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1990,375(4):225-230
Zusammenfassung Proximale Humerusfrakturen gehö-ren zu den häufigen Verletzungen des ä1teren Menschen. Gering dislozierte Brüche können mit gutem Erfolg konservativ behandelt werden. Therapeutische Schwierigkeiten bereiten vor allem dislozierte Mehrfragment- oder Trümmerfrakturen des Oberarmkopfes. Im Zeitraum von 1970–1988 wurde in unserer Klinik in dieser Situation bei 8 Patienten eine Resektion des Humeruskopfes durchgeführt. 6 Patienten konnten bei einer mittleren Beobachtungszeit von 69 Monaten nachuntersucht werden. Alle Patienten wiesen postoperativ eine erhebliche Bewegungseinscänkung im betroffenen Schultergelenk auf. Die durchschnittliche Abduktion betrug 60° (40–80dg), die Anteflexion 60° (40–80°) bei einer mittleren AuBenrotation von 17° (5–30°) und Innenrotation von 48° (5–90°). Eine Patientin war postoperativ schmerzfrei, 2 weitere verspürten nächtliche Schmerzen, während die übrigen 3 Patienten fiber eine unterschiedliche Schmerzsymptomatik klagten. Dennoch waren 5 der 6 Patienten mit dem Operationsergebnis zufrieden, eine Patientin bewertete das Resultat mit gut.
Resection of the humeral head in cases of head-splitting humeral fractures — results
Summary Proximal humeral fractures are frequent injuries in older patients. Most of these fractures respond satisfactorily to conservative treatment. Problems arise in cases of four-part displacements and in head-splitting fractures with massive defects in the articular surface. Between 1970 to 1988 eight patients were treated in our clinic in this situation by resection of the humeral head. 6 patients could be followed-up for an average of 69 months. Postoperative findings showed a restricted range of motion in all operated shoulders. The average abduction of the arm was 6° (40-80°) and elevation 60° (40–80°). The patients showed a mean external rotation of 17° (5–30°) and an internal rotation of 48° (5–90°). Only one patient was painless, 2 patients had pain during the night, and 3 patients suffered from various pain symptoms. Nevertheless 5 of 6 patients assessed the result as satisfactory and one patient as good.相似文献