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51.
52.
Serial pulmonary imaging has proved to be effective in the evaluation of patients undergoing total joint arthroplasty. A clinical dilemma arises in asymptomatic patients whose postoperative pulmonary images differ from the preoperative images. The authors prospectively evaluated 403 patients with serial imaging to determine the significance of changed postoperative images in asymptomatic patients undergoing total hip or knee arthroplasty. Twenty-two (5.5%) patients had significant changes on postoperative images. Seventeen were asymptomatic; all but one underwent pulmonary angiography. Documented pulmonary emboli were demonstrated in 100% of patients whose postoperative images changed to indicate a high probability of pulmonary embolism, 71% whose images changed to a moderate probability, and 0% whose images changed to indeterminate probability. Overall, pulmonary emboli occurred in 76% of all asymptomatic patients with significantly change postoperative images. Asymptomatic pulmonary embolism is a significant occurrence after total hip or knee repair, and a changed lung scan with appropriate clinical evaluation is an accurate indicator of pulmonary emboli in asymptomatic postarthroplasty patients.  相似文献   
53.
Insertion of a screw biopsy stylet into a thin-walled biopsy needle greatly enhances detection of the needle during ultrasound-guided percutaneous biopsy. This technique is helpful when precise needle-tip localization is needed for biopsies of small lesions.  相似文献   
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55.
Anti-Sc1 was detected in a gravida-2 patient at 12 weeks' gestation. At 29 weeks, the antibody was found to be of the IgG3 subclass with a titer of 16, score 36, by the indirect antiglobulin test, and it produced 7 percent lysis by antibody-dependent cellular cytotoxicity (ADCC) assay, a finding that suggested an unaffected fetus. The titer remained constant throughout the pregnancy, as did the IgG subclass and activity in the ADCC assay. At delivery of the full-term infant, the cord hemoglobin was 13.5 g per dL and the direct antiglobulin test was positive (3+) with anti-IgG. The infant did not require transfusion. A sample taken 9 weeks after delivery showed 44 percent lysis in the ADCC assay. The anti-Sc1 titer was 32, score 65.  相似文献   
56.
Complications of epidural anesthesia: MR appearance of abnormalities   总被引:5,自引:0,他引:5  
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57.
Chronic sun exposure leads to photodamage, which is characterized clinically by fine and coarse wrinkles, dyspigmentation, telangiectasia, laxity, roughness and a sallow appearance. Many treatments claim to reduce the signs of photodamage, however evidence from randomized controlled trials (RCT) to support these claims is limited. The use of topical retinoids, particularly tretinoin, isotretinoin and tazarotene, has been shown to significantly reduce signs of photodamage both clinically and histologically. Over recent years a number of RCTs, have affirmed that topical tazarotene is an effective and safe treatment for photodamaged skin.  相似文献   
58.
Low-level echogenicity in intraventricular hemorrhage versus ventriculitis   总被引:1,自引:0,他引:1  
Grant  EG; White  EM; Schellinger  D; Rosenbach  D 《Radiology》1987,165(2):471-474
Serial cranial sonograms of 55 neonates with large perinatal intraventricular/intraparenchymal hemorrhages and moderate-to-severe posthemorrhagic hydrocephalus were reviewed. In all 55 patients, the ventricles were initially enlarged and filled with anechoic cerebrospinal fluid, which contained discrete hyperechoic fragments of hematoma. Between 7 and 25 days after the initial hemorrhagic episode, however, diffuse, low-level echogenicity appeared in the ventricles of 34 patients. The low-level echogenicity was transient and persisted for 7-59 days (average, 18 days). In 32 patients, low-level echogenicity was a benign finding associated with prior intraventricular hemorrhage. In two patients, the low-level echogenicity was associated with ventriculitis. Low-level echogenicity appeared, increased, then cleared, but reappeared with the onset of ventriculitis in these two patients. Thickening of the ependyma and abnormal periventricular echogenicity, signs of inflammation, were also present. Although low-level echogenicity may commonly be a benign finding, the possibility of ventriculitis should not be ignored.  相似文献   
59.
There have been anecdotal reports describing patients with systemic lupus erythematosus (SLE) and inappropriately elevated secretion of antidiuretic hormone (ADH), but no systematic studies of ADH and its metabolism in SLE have been performed. We measured plasma ADH levels in 36 stable SLE patients with normal renal function and examined the relationship of the circulating ADH concentration to clinical disease activity and effective extracellular fluid volume as reflected by peripheral plasma renin activity (PRA) and plasma aldosterone concentration. The mean ADH level was elevated, 11.4 +/- 1.0 microU/ml (normal 0.4-1.4 microU/ml), while mean PRA and aldosterone were 5.4 +/- 0.6 ng/ml/h and 10.6 +/- 1.6 ng/100 ml, respectively. When patients were divided into two groups according to disease duration, those with SLE for 2 years or more had significantly higher plasma ADH levels (13.9 +/- 1.4 vs. 7.7 +/- 0.9 microU/ml; p less than 0.001 and urinary osmolality (697 +/- 63 vs. 445 +/- 49 mosm/kg; p less than 0.02) compared to those with SLE of less than 2 years duration. No differences in serum Na+, K+, PRA, plasma aldosterone concentration, C3, or 24-hour urinary protein excretion were noted between these two groups. Six patients with SLE for less than 2 years underwent a standard water load (20 ml/kg); in 3/6 there was a paradoxical increase in the plasma ADH concentration. These findings indicate that SLE is associated with elevated plasma ADH levels that increase with prolonged disease duration. This abnormality is unrelated to the usual serologic indices of SLE activity, effective extracellular fluid volume status, or any apparent renal unresponsiveness to ADH.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
60.
SUMMARY Four cases of primary meningococcal conjunctivitis in children are reported. This represents an incidence of 2% of patients presenting with conjunctivitis to a paediatric A&E department. All were initially treated with topical chloramphenicol, followed by systemic rifampicin once the diagnosis had been established. No ocular or systemic complications developed, nor recolonisation of the conjunctiva or colonisation of the nasopharynx at follow-up (1–2 years).  相似文献   
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