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This study validates a new quantitative myocardial perfusion SPECT software. METHODS: The processing starts with the extraction of the morphologic skeleton of the left ventricular myocardium from reconstructed transverse sections. Fuzzy logic is used to decide whether a pixel belongs to the myocardium and any perfusion defect is filled according to a truncated bullet model. The resulting image is partitioned in 18 isovolumetric sectors. Sex-matched normal limits, criteria of abnormality for rest (201)Tl and (99m)Tc-labeled perfusion tracers, reproducibility studies, and detection of coronary artery disease were developed and validated in an overall population of 343 patients. The sex- and tracer-matched means and SDs of a normal response were calculated in 93 male and 93 female patients with a <5% likelihood of coronary artery disease. Reproducibility measurements and assignment of different sectors of the myocardium to a specific coronary were performed from data collected in 49 and 60 patients, respectively. The accuracy of the detection of a coronary artery occlusion was assessed in 48 patients who also underwent coronary angiography. RESULTS: The intra- and interoperator reproducibility of the sectorial activity was high with a linear regression coefficient of 0.97 and a SD of the difference measurement at 4.4% and 3.8%, respectively. Overall sensitivity and specificity for the detection of occluded coronary artery were 90% and 80%, respectively. For the detection of left anterior descending, left circumflex, and right artery coronary occlusion, sensitivity was 92%, 75%, and 92.5%, respectively, and specificity was 75%, 78%, and 90%, respectively. CONCLUSION: The new quantitative myocardial perfusion SPECT software appears to be a very helpful program for the objective analysis of perfusion tracer distribution in myocardial SPECT and a very accurate tool in the detection and localization of coronary artery occlusion.  相似文献   
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The philosophy of family centered care in a newborn intensive care unit encourages not only parent participation but involvement of the well sibling in the family process. This article describes how a group of staff nurses fostered the emotional well-being of the ill neonates's sibling by changing the status of sibling visitation in their unit.  相似文献   
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The case of a 43 year old male with giant chest wall tumor weighing 9.6 kg verified as chondrosarcoma is described. The patient was treated by multiple (six times) surgical procedures including left costopleuropneumonectomy and left subclavian artery end-to-end anastomosis between 1998 and 2005. Despite the palliative character of surgery, he achieved long-term survival but finally refused next surgery due to the risk of left upper limb amputation and died a few months later.  相似文献   
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Loss of a thumb accounts for 60% decrease of functional value of the hand, thus any attempt of it's reconstruction is a priority in the field of hand surgery. Optimal reconstructive solution for subtotal thumb amputations has not been settled. The results of partial pollicization of ring finger in 5 adult men is presented. Four patients sustained distal subtotal thumb amputation (MCP joint level), one total amputation. In three patients the distal phalange of the ring finger was transferred with the DIP joint, FDP tendon and a fragment of extensor tendon. An effective movement of a newly created thumb's IP joint was achieved in two patients. In one patient with a total thumb amputation the transfer was followed by a pollicization of the second metacarpal with remnants of proximal phalange. The postoperative course was uneventful in all of the patients. The sensitivity tested on the pulp of the transferred finger equalized to the preoperative value, the hand strength was not diminished. The cosmetic result was excellent.  相似文献   
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Anterior vertical fusion of the tracheal cartilages with normal pars membranacea is a rarely described tracheal anomaly. We report four cases of this anomaly, three associated with craniosynostosis syndromes and one with Goldenhar's syndrome. The anomaly was documented at postmortem examination in one case, both endoscopically and at tracheotomy in two cases, and endoscopically in one case. Documentation from gross postmortem photographs, photomicrographs, and intraoperative endoscopic photographs is presented so that the anatomical aspects of this anomaly can be thoroughly understood and recognized. All four newborn patients developed recurrent lower respiratory tract infections, reactive airway disease, and chronically retained secretions attributable to this anomaly. Neither tracheal stenosis nor stridor was encountered. In the three surviving patients, the infections grew less frequent and less severe in later childhood. These observations suggest that this tracheobronchial anomaly may be associated with a variety of craniofacial syndromes and may alter airflow dynamics in a way that predisposes to retained secretions and chronic pulmonary disease.  相似文献   
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The cup-disk ratio (CDR), the size of the neuroretinal rim area as well as the other disk parameters investigated with the Optic Nerve Head Analyzer (ONHA) were measured in double examinations of 32 healthy eyes in 32 patients. Thus, "normal" values were determined for the various disk parameters. A new method is presented for calculating one average pallor value for the disk. The mean value for disk pallor in healthy eyes is determined. Examination of the CDR in the quadrants of the disk reveals significant differences. According to the results of a multi-regressional analysis of the various disk parameters, the size of the neuroretinal rim area in healthy eyes is influenced by the size of the disk, the disk volume and the elevation volume. The correlation between the size of the neuroretinal rim area and the size of the disk reveals a significant interdependence: a larger disk also has a greater neuroretinal rim area as compared to a smaller disk. This means that sizes of neuroretinal rim areas of different disk should only be compared when the disks are the same size. Relative values, such as the CDR or the ratio between the size of the neuroretinal rim area and disk size (rim area/disk area), are therefore better suited for comparison.  相似文献   
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