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51.
Sarcomas of the breast are relatively rare and account for 1% of all primary malignant tumors of the breast. Pure and primary chondrosarcoma of the male breast is an extremely rare tumor. It may arise either from the breast stroma itself or from underlying bone or cartilage. Differential diagnoses include cystosarcoma phyllodes and breast metaplastic carcinoma with chondroid differentiation.  相似文献   
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The accuracy of a radiographic absorptiometry (RA) technique called digital image processing (DIP), discriminative ability of RA for osteoporotic fracture, and the relationship between RA and dual X-ray absorptiometry (DXA) of the spine and forearm were evaluated. We measured 16 cadaver hands, 32 healthy non-black premenopausal women, 39 healthy non-black postmenopausal women, and 35 non-black osteoporotic postmenopausal females. The overall correlation between the ash weights of the entire metacarpal and the DIP values was excellent (r = 0.954, P < 0.001, SEE = 0.14, CV = 6.4%). Short-term precision error of DIP was 3.5%. Age-related bone loss determined by DIP is comparable to that of spinal and forearm DXA: annual BMD decreases were 0.46% for DIP, 0.45% for forearm, and 0.32% for the spine. DIP of the 2nd metacarpal shows a gradient of risk for spinal fracture only slightly below that of forearm DXA, but substantially below that of spinal DXA. Age-adjusted odds ratios were 1.81 for RA, 2.45 for spinal DXA, and 1.94 for forearm DXA. Received: 2 July 1996 / Accepted: 2 July 1997  相似文献   
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Background:  The purpose of the study was to compare the success and ease of insertion of three techniques of laryngeal mask airway (LMA) insertion; the standard Brain technique, a lateral technique with cuff partially inflated and a rotational technique with cuff partially inflated.
Methods:  One hundred and sixty-eight ASA I and II children aged 6 months to 6 years undergoing short elective surgical procedures lasting 40–60 min were included in the study. A standard anesthesia protocol was followed for all patients. Patients were randomly allocated into one of the three groups i.e. standard (S), rotational (R) and lateral (L). The primary outcome measure of the study was success rate at the first attempt using three techniques of LMA insertion. Secondary outcomes measures studied were overall success rate, time before successful LMA insertion, complications and maneuvers used to relieve airway obstruction.
Results:  Successful insertion at the first attempt was significantly higher in group R (96%) compared with group L (84%) and group S (80%) ( P  =   0.03). Overall success rate (i.e. successful insertion with two attempts) was 100% for group R, 93% for group L and 87% for group S ( P  =   0.03). Time for successful insertion was significantly lower in group R compared with group L and S ( P  <   0.001). The incidence of complications was lower in group R.
Conclusions:  A rotational technique with partially inflated cuff is associated with the highest success rate of insertion and lowest incidence of complications and could be the technique of first choice for LMA insertion in pediatric patients.  相似文献   
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BACKGROUND: This study was designed to investigate whether a fall in heart rate (HR) with injection of local anesthetic into the caudal space can be used as a predictor of correct needle placement. METHODS: Two hundred and twenty pediatric patients undergoing infraumbilical surgery were recruited to the study. After induction of general anesthesia, baseline HR was recorded and caudal block was performed using 0.75-1 ml x kg(-1) 0.25% bupivacaine, which was injected at a rate of 1 ml x 3 s(-1). The change in HR while injecting an initial 0.2 ml x kg(-1) of drug and during total drug injection was recorded. HR reduction of > or = 3 b x min(-1) was considered a positive test for correct needle placement. The success of block was judged by HR response to skin incision, endtidal halothane concentration required for maintenance of anesthesia and postoperative pain scores. RESULTS: Caudal block was successful in 209/220 (95%) patients. Mean HR following the initial drug injection (111 +/- 17.7, P < 0.01) and entire drug injection (108.8 +/- 17.2, P < 0.01) was significantly lower than baseline (116.2 +/- 17.5). HR reduction of > or = 3 b x min(-1) was present in 190/209 and 199/209 successful block following initial drug injection and total drug injection respectively. The analysis of study data showed that a fall in HR is a predictor of successful caudal block, with a sensitivity of 90.9%, specificity of 100% and a positive predictive value of 100% after initial injection of local anesthetic. CONCLUSIONS: We conclude that decrease in HR with drug injection is a simple, objective and reliable test to predict success of caudal block.  相似文献   
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Fetal diastematomyelia is a rare form of spinal dysraphism that is characterized by a complete or incomplete division of the spinal cord by an osseous or fibrocartilaginous septum. A case of diastematomyelia, which was detected on the routine third trimester detailed ultrasound scan, is presented. The diagnosis was based on the detection of an echogenic focus in the posterior aspect of the spine in association with widening of the interpedicular vertebral space. The case illustrates that diastematomyelia can occur in the absence of overt spina bifida and that prenatal detection will allow timely postnatal investigation and treatment. Prenatal literature is further reviewed to assess the clinical significance of this finding.  相似文献   
59.
Tyler D  Mandybur G  Dhillon G  Fratkin J 《Neurosurgery》2001,48(4):937-9; discussion 939-40
OBJECTIVE AND IMPORTANCE: Parathyroid carcinoma is a rare entity, and fewer than 200 cases have been described. It is a slowly progressive disease characterized by frequent recurrences and local metastases. Most patients with parathyroid carcinoma die from metabolic complications of hyperparathyroidism. Five-year survival rates range from 25 to 50%. Functional parathyroid carcinoma is a rare cause of hyperparathyroidism that affects only 0.32 to 5% of all patients who undergo surgery for hypercalcemia. A review of the literature revealed only one other reported case of metastatic intracranial parathyroid carcinoma, in a patient who experienced local recurrence and metastatic disease when she was diagnosed with an intracranial lesion. CLINICAL PRESENTATION: We report the case of a 44-year-old African-American man with recent-onset, right lower-extremity weakness and hypercalcemia 4 years after he underwent a parathyroidectomy for parathyroid carcinoma. At presentation, his parathyroid level was 467 pg/ml, and his serum calcium level was 15.2 mg/dl. Imaging studies revealed an isolated enhancing left mesial frontoparietal mass. A systemic Cardiolite study demonstrated a single focus of radiotracer uptake in this region. No abnormal uptake was demonstrated in the neck or elsewhere. INTERVENTION: The patient underwent a frameless stereotactic interventional magnetic resonance imaging-guided resection via a parasagittal interhemispheric approach. Pathological findings were consistent with parathyroid carcinoma. After resection, his right lower-extremity weakness and secondary hyperparathyroidism resolved. CONCLUSION: The typical natural history of parathyroid carcinoma concludes with death from complications of hyperparathyroidism. This case report supports aggressive surgical management to eliminate all parathyroid hormone-secreting malignant tissue and prevent metabolic complications. In this patient, intraoperative magnetic resonance imaging was helpful to ensure complete resection.  相似文献   
60.
The recurrence of pressure ulcers (PrUs) and dehiscence of reconstructive flap have always been a problem. The present study aimed to evaluate the results of reconstructive flap surgeries in patients with spinal cord injury (SCI) having PrUs, using classic and modified flaps with improvisations to decrease wound dehiscence, flap necrosis and tension in flap. This is a prospective clinical study. The setting was a tertiary care centre in northern India. Thirty‐five patients with SCI having 37 stage III and IV PrUs. PrUs were treated using classic and modified flaps with improvisations. The outcome was evaluated using criteria of wound dehiscence, flap necrosis and recurrence. The results of flap surgery were excellent in 32 (86·48%) patients, good in 4 (10·81%) patients and poor in 1 (2·7%) patient. Partial flap necrosis (2·7%), low incidence of PrU recurrence rate at flap site (5·4%) and overall PrU recurrence (11·4%) were the complications observed. Improvisation of classic and modified techniques of flap surgeries along with reinforcement of general care principles of paraplegia can be effective in minimising complications often associated with PrU reconstructive surgery thus improving the ultimate outcome.  相似文献   
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