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41.
The effects of respiratory movements on the ultrasonic echoes of the cardiac structures were recorded and analyzed in 50 consecutive patients. Deep inspiration in cooperative patients resulted in a considerable increase of dense anterior echoes, with blotting out of any distal or posterior echoes in 12 of 44 patients (group A). In the second or larger series (32 of 44 patients; group B), a posterior displacement of most of the identifiable intrinsic cardiac echoes was seen with deep inspiration, particularly those of the posterior wall of the left ventricle. Forced expiration produced an opposite or anterior displacement of the cardiac echoes. Normal respirations showed similar but smaller excursions. 相似文献
42.
A splicing mutation accounts for the lack of p53 gene expression in a CML blast crisis cell line: a novel mechanism of p53 gene inactivation 总被引:2,自引:0,他引:2
Alterations of the p53 anti-oncogene have recently been found to occur frequently in the blast crisis of chronic myelocytic leukaemia. The p53 gene may be altered by gross structural alterations or by point mutations in the coding sequence. We now report a novel mechanism of gene inactivation in a blast crisis cell line where a mutation in a splice donor site at the 5' end of the fifth intron of the gene interrupts RNA processing and gene expression. 相似文献
43.
Hoheisel G Wu A Lee N Chan CH Wong KT Ahuja A Joynt GM Chung SC Sung JJ Hui DS 《Pneumologie (Stuttgart, Germany)》2003,57(6):315-321
The severe acute respiratory syndrome (SARS) is a highly infectious respiratory disease, to the best of our knowledge caused by a hitherto unknown corona virus. The virus has spread from South East Asia to many countries of the world. Three case reports of patients from the Prince of Wales Hospital of The Chinese University of Hong Kong demonstrate typical clinical courses. Fever, cough, in most cases non-productive, myalgia, chills, and rigor are the leading symptoms. Leucopenia and thrombocytopenia are the most prominent laboratory parameters, increased values for lactatedehydrogenase (LDH) reflect a more severe clinical course. Advanced age and coexisting conditions seem to influence the prognosis unfavourably. The chest roentgenogram may be normal initially but at a later stage progressive consolidations in the majority of peripheral parts of the lung are observed, which cannot be differentiated from pneumonias of other origin. Even young patients can enter a stage of respiratory compromise rather fast. A therapy against the cause of the disease is not known. Empirical therapy with ribavirin in combination with high dose corticosteroids have proved successful. The disease may progress into respiratory failure comparable with an acute respiratory distress syndrome (ARDS). Mortality is around five to ten per cent. Stringent hygiene and quarantine measures are mandatory to prevent the further spread of this threatening disease. 相似文献
44.
Clinical features and investigative findings in presence of mitral leaflet prolapse. Study of 85 consecutive patients. 下载免费PDF全文
In a 14-month period mitral leaflet prolapse was diagnosed in 85 patients by echocardiography or cineangiography. Chest pain alone was the presenting complaint in 30 patients and linked with palpitation, dyspnoea, or syncope in 9. Eleven presented with major neurological disturbances (9 had transient ischaemic attacks), 10 with palpitation, 4 with undue and persistent fatigue, 2 with dyspnoea, and 2 with dizziness. Seventeen were referred not because of symptoms but because of clicks and murmurs. Overall, chest pain affected 61 patients and unless associated with coronary artery disease was not anginal. Palpitation was admitted by 42 patients; dizziness, lightheadedness, or paraesthesiae by 15, and syncope by 12. Systolic auscultatory abnormalities were noted in 69: 25 had single clicks, 3 had multiple clicks, 19 had both click(s) and murmur, and 22 had a murmur alone. Electrocardiography revealed ST segments flat for greater than 0-10 s in 21, prolonged QTc in 18, and T wave flattening or inversion in inferior limb and lateral chest leads in 14. The exercise stress test was abnormal in 13 of 27 patients. Mitral valve echograms showed definite mitral leaflet prolapse in 61, 'possible' prolapse in 14, and were normal in 8 patients with angiographic proof of mitral leaflet prolapse. Cardiac catheterization with left ventriculography showed prolapse of posterior mitral leaflet in 36, of both leaflets in 2, and left ventricular wall motion abnormalities in 16 cases. Selective coronary arteriography in 31 cases showed major vessel narrowing of larger than or equal to 80 per cent lumen diameter in 4, all with angina. This consecutive series indicates that the physical event of mitral leaflet prolapse is more common than hitherto appreciated, is priminently associated with non-anginal chest pain, palpitation, and neurological disturbances, and in 90 per cent of cases could be shown echocardiographically. 相似文献
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Background
To study insertion of LPS and correlate anatomically the formation of superior palpebral crease and its clinical relevance in section of Indian population.Methods
Twenty-five human eyelids from cadavers ranging from 15–80 years were studied by dissection and histology.Results
The levator aponeurosis traverses through interfascicular space of orbicularis oculi with twenty four inserting into subcutaneous tissue. Low septo aponeurotic sling or preaponeurotic fat was not observed. Lower one third tarsal insertion seen in twenty four specimens. Fibres become denser as it reaches the connective tissue anterior to tarsal plate. The crease was at different levels in relation to the tarsal insertion.Conclusion
The aponeurosis insertion is either to the skin, the subcutaneous tissue or into the interfascicular space of the orbicularis. The present study reaffirms the insertion of LPS to the subcutaneous tissue of the eyelid with an extension reaching lower one third of the tarsal plate. The tissues in the anterior tarsal plate are closely packed but to act as a single complex to form a dynamic crease has not been confirmed in the study. No gross or histological difference was observed in the skin of the eyelid in the vicinity of the crease. The pattern of insertion of LPS aponeurosis plays a direct role in the formation of superior palpebral crease an important role in surgeries for Ptosis. The eyelids studied were of Indian origin with crease, and further comparative studies needs to be done for the precise anatomical explanation of single fold eyelids. 相似文献49.