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The authors retrospectively reviewed the computed tomographic (CT) scans, biopsy specimens, autopsy results, and lobectomy specimens of 21 patients who had lymphangitic carcinomatosis. Ten-millimeter collimation CT scans were obtained from all patients, and selected 1.5-mm CT scans were obtained from ten patients. In five patients, the diagnosis was established with open lung biopsy, lobectomy, or autopsy; in nine, with bronchial biopsy or transbronchial biopsy; and in seven, with clinical and radiologic criteria. Certain characteristic findings on CT scans were evident: uneven thickening of bronchovascular bundles, thickening of isolated interstitial lines, and the presence of polygonal lines. These findings may be seen on CT scans even if the findings on chest radiographs are normal or nonspecific. The pathologic basis for these characteristic CT findings may relate to tumor thrombi in lymphatic vessels rather than edema and fibrosis, at least in the early stages of disease. 相似文献
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心房扑动患者的下腔静脉-三尖瓣环峡部和房间隔缓慢传导的电生理意义 总被引:1,自引:0,他引:1
目的 用电 解剖标测方法标测右心房 ,然后比较心房扑动 (AFL)和房室结折返性心动过速(AVNRT)患者在下腔静脉 三尖瓣环峡部 (CTI)和心房间隔部 (AS)的电冲动传导速度 ,以便确定AFL患者除了解剖结构上的异常外 ,是否伴有心房电生理方面的异常变化。方法 1 0例AFL患者 ,男性 7例 ,女性 3例 ,平均 (53± 1 0 )岁 ;1 3例AVNRT患者 ,男性 5例 ,女性 8例 ,平均 (51± 1 1 )岁。对这两组患者进行了详细的电 解剖标测、电生理检查和射频消融术。分别以周长为 60 0、40 0、和 30 0ms在冠状静脉窦 (CS)起搏的情况下测量AFL和AVNRT患者的CTI和AS的冲动传导速度 ,并将两组患者在CTI和AS的冲动传导速度进行比较。结果 与AVNRT患者相比 ,AFL患者在各个起搏周长 (PCL)时CTI和AS的冲动传导速度都明显减慢 (P <0 0 5)。另外 ,在AFL组 ,AS的冲动传导速度在起搏周长 60 0、40 0ms时低于CTI,但在 30 0ms时差异无显著性 (P >0 0 5)。因为在AFL组 ,PCL为 30 0ms时的冲动传导速度明显低于 60 0和 40 0ms时的冲动传导速度 ,致使PCL为 30 0ms时CTI和AS的冲动传导速度差异无显著性。结论 与CTI相比 ,AS的冲动传导速度在所有患者都较慢 ,而AFL患者在CTI和AS的冲动传导速度减低更明显 ,并且在CTI的冲动传导速度减慢具有频率依 相似文献
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Pulmonary alveolar proteinosis: CT findings 总被引:16,自引:0,他引:16
In pulmonary alveolar proteinosis (PAP), a proteinaceous material accumulates in the alveolar air spaces, causing hypoxemia, restrictive lung disease, and dramatic abnormalities on chest radiographs. Complications are unusual, but of the ones that do occur, infection, particularly with Nocardia asteroides, and fibrosis are the most common. Few computed tomographic (CT) studies of this condition have been reported. The CT scans of nine patients with PAP were reviewed. Varying combinations of air-space and interstitial patterns were seen. The CT appearance of air-space disease ranged from ill-defined nodules to patchy consolidation to large regions of confluence. Air-space consolidation was sometimes sharply demarcated from surrounding normal lung tissue, which created a geographic pattern. Despite the predominance of air-space patterns, air bronchograms were not a prominent feature. CT showed the interstitial component of disease and the extent of disease more clearly than did plain radiography. In two cases, CT demonstrated focal pneumonia that was not visible on the radiographs. 相似文献
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Low-dose high-resolution CT of lung parenchyma 总被引:15,自引:0,他引:15
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A linear peristaltic infusion device was evaluated for red cell (RBC) transfusion in the pediatric and neonatal setting. CPDA-1 RBC units (n = 24) divided into six groups of 4 units each underwent simulated transfusion. Blood was infused by using manufacturer-provided administration sets with either a 21-gauge needle or a 24-gauge catheter. Filters were used in two groups to evaluate the effect of negative pressure on filter function. Two groups of RBCs less than 1 week old were washed, irradiated, and infused at 5 mL per hour, by using a standard administration set, or at 10 mL per hour, by using a syringe set. Four-week-old RBCs (washed and irradiated, irradiated and filtered, filtered only, or unmanipulated) were infused at 100 mL per hour. Paired samples from 0 and 2 hours before and after infusion were analyzed for hemoglobin, hematocrit, RBC count, plasma hemoglobin, lactate dehydrogenase, potassium, alanine aminotransferase, and aspartate aminotransferase. Hausser and Nageotte hemocytometers were used to perform white cell (WBC) counts when a filter was used. By analysis of variance and percentage of change, data from 0 and 2 hours before and after infusion were compared. No clinically or statistically significant differences were seen for hemoglobin, hematocrit, or RBC count. The difference in preinfusion and postinfusion plasma hemoglobin levels in washed RBCs at 2 hours was statistically but not clinically significant (14.5 +/− 6.8 vs. 19.3 +/− 7.1 mg/dL). No clinically significant differences were noted for the remaining analytes.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献