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排序方式: 共有684条查询结果,搜索用时 15 毫秒
591.
Sarcoidosis: correlation of pulmonary parenchymal pattern at CT with results of pulmonary function tests 总被引:1,自引:0,他引:1
Bergin CJ; Bell DY; Coblentz CL; Chiles C; Gamsu G; MacIntyre NR; Coleman RE; Putman CE 《Radiology》1989,171(3):619-624
The appearances of the lungs on radiographs and computed tomographic (CT) scans were correlated with degree of uptake on gallium scans and results of pulmonary function tests (PFTs) in 27 patients with sarcoidosis. CT scans were evaluated both qualitatively and quantitatively. Patients were divided into five categories on the basis of the pattern of abnormality at CT: 1 = normal (n = 4); 2 = segmental air-space disease (n = 4); 3 = spherical (alveolar) masslike opacities (n = 4); 4 = multiple, discrete, small nodules (n = 6); and 5 = distortion of parenchymal structures (fibrotic end-stage sarcoidosis) (n = 9). The percentage of the volume judged to be abnormal (CT grade) was correlated with PFT results for each CT and radiographic category. CT grades were also correlated with gallium scanning results and percentage of lymphocytes recovered from bronchoalveolar lavage (BAL). Patients in CT categories 1 and 2 had normal lung function, those in category 3 had mild functional impairment, and those in categories 4 and 5 showed moderate to severe dysfunction. The overall CT grade correlated well with PFT results expressed as a percentage of the predicted value. In five patients, CT scans showed extensive parenchymal disease not seen on radiographs. CT grades did not correlate with the results of gallium scanning or BAL lymphocytes. The authors conclude that patterns of parenchymal sarcoidosis seen at CT correlate with the PFT results and can be used to indicate respiratory impairment. 相似文献
592.
593.
Velardi A; Terenzi A; Cucciaioni S; Millo R; Grossi CE; Grignani F; Martelli MF 《Blood》1988,71(5):1196-1200
Peripheral blood T cell subsets were evaluated in 11 patients during the reconstitution phase after allogeneic bone marrow transplantation and compared with 11 age-matched controls. The proportion of cells coexpressing Leu7 and CD11b (C3bi receptor) markers was determined within the CD4+ (T-helper) and the CD8+ (T-suppressor) subsets by two- color immunofluorescence analysis. CD4+ and CD8+ T cells reached normal or near-normal values within the first year posttransplant. In contrast to normal controls, however, most of the cells in both subsets coexpressed the Leu7 and CD11b markers. T cells with such phenotype display the morphological features of granular lymphocytes (GLs) and a functional inability to produce interleukin 2 (IL 2). These T cell imbalances were not related to graft v host disease (GvHD) or to clinically detectable virus infections and may account for some defects of cellular and humoral immunity that occur after bone marrow transplantation. 相似文献
594.
CE Richards M. Drayton H. Jenkins TJ Peters 《Acta paediatrica (Oslo, Norway : 1992)》1993,82(8):678-682
Richards CE, Drayton M, Jenkins H, Peters TJ. Effect of different chloride infusion rates on plasma base excess during neonatal parenteral nutrition. Acta Pædiatr 1993;82:678–82. Stockholm. ISSN 0803–5253
Routine biochemical monitoring of parenterally fed newborn infants revealed plasma chloride levels which were higher than widely quoted reference ranges. The parenteral nutrition solutions were reformulated to reduce the chloride infusion rate. In a historically controlled study, 28 infants receiving the original formulation were compared with 31 infants receiving the new formulation. The mean plasma chloride level was 4.8 mmol/l lower in the new formulation group than in the original formulation group (95% confidence interval 2.5–7.2 mmol/l). The mean base excess level was 3.1 mmol/l higher in the new formulation group than in the original formulation group (95% confidence interval 1.9–4.8 mmol/l). A reduction in the chloride load by using acetate salts can be safely achieved and may decrease the plasma chloride levels and decrease acidosis during the first seven days of life. 相似文献
Routine biochemical monitoring of parenterally fed newborn infants revealed plasma chloride levels which were higher than widely quoted reference ranges. The parenteral nutrition solutions were reformulated to reduce the chloride infusion rate. In a historically controlled study, 28 infants receiving the original formulation were compared with 31 infants receiving the new formulation. The mean plasma chloride level was 4.8 mmol/l lower in the new formulation group than in the original formulation group (95% confidence interval 2.5–7.2 mmol/l). The mean base excess level was 3.1 mmol/l higher in the new formulation group than in the original formulation group (95% confidence interval 1.9–4.8 mmol/l). A reduction in the chloride load by using acetate salts can be safely achieved and may decrease the plasma chloride levels and decrease acidosis during the first seven days of life. 相似文献
595.
T Gozzi CE Flück D L’Allemand MT Dattani PC Hindmarsh PE Mullis 《Acta paediatrica (Oslo, Norway : 1992)》2010,99(4):569-574
Aim: An impressive discrepancy between reported and measured parental height is often observed. The aims of this study were: (a) to assess whether there is a significant difference between the reported and measured parental height; (b) to focus on the reported and, thereafter, measured height of the partner; (c) to analyse its impact on the calculated target height range. Methods/Results: A total of 1542 individual parents were enrolled. The parents were subdivided into three groups: normal height (3–97th Centile), short (<3%) and tall (>97%) stature. Overall, compared with men, women were far better in estimating their own height (p < 0.001). Where both partners were of normal, short or tall stature, the estimated heights of their partner were quite accurate. Women of normal stature underestimated the short partner and overestimated the tall partner, whereas male partners of normal stature overestimated both their short as well as tall partners. Women of tall stature estimated the heights of their short partners correctly, whereas heights of normal statured men were underestimated. On the other hand, tall men overestimated the heights of their female partners who are of normal and short stature. Furthermore, women of short stature estimated the partners of normal stature adequately, and the heights of their tall partners were overestimated. Interestingly, the short men significantly underestimated the normal, but overestimated tall female partners. Conclusion: Only measured heights should be used to perform accurate evaluations of height, particularly when diagnostic tests or treatment interventions are contemplated. For clinical trails, we suggest that only quality measured parental heights are acceptable, as the errors incurred in estimates may enhance/conceal true treatment effects. 相似文献
596.
Benign postoperative biliary strictures in 74 patients were dilated percutaneously with balloon catheters. In all cases, dilation was performed with fluoroscopic guidance in a radiology suite. Lasting patency following removal of biliary stents occurred in 73% of 49 patients with biliary-enteric anastomotic strictures and in 88% of 25 patients with primary ductal strictures, for an overall success rate of 78%. A successful outcome was more likely if the interval between the last biliary tract surgery and balloon dilation exceeded 2 years. Stricture patency was more easily achieved in patients with primary ductal strictures than in those with biliary-enteric anastomotic strictures. Serious, procedure-related complications were encountered when strictures were dilated transhepatically; these included sepsis in 18 of 65 patients and bleeding due to arteriobiliary communications in seven. No serious complications occurred when strictures were dilated via a T tube track, making this the preferred route if available. Surgeons should be encouraged to leave T tubes in place if postoperative biliary stricture is suspected. Balloon dilation should be strongly considered in patients with benign postoperative strictures in whom surgical repair is difficult. 相似文献
597.
CT measurement of the diameter of spinal and other bony canals: effects of section angle and thickness 总被引:2,自引:0,他引:2
The effects of section angle and thickness on the measurement of spinal canal diameter by computed tomography (CT) were tested. A phantom of three spinal canals was constructed of three Lucite rods of different diameters, each covered with 1.8-mm-thick Teflon. A second phantom was constructed of two Lucite rods of the same diameter covered with 1.8- and 8.8-mm-thick Teflon, respectively. CT sections 10, 5, and 1.5 mm thick were obtained at various angles relative to the transverse plane of each canal. Anteroposterior diameters were measured at bone window settings using a standard software package and a method that uses a CT-number profile. Results show that sections obtained at an angle to the transverse plane of the canal do not always overestimate its diameter, as previously suggested, but can make it appear artifactually stenotic. The effect is from volume averaging and is most marked when thick, severely angled sections are used. 相似文献
598.
Cholangiocarcinoma complicating primary sclerosing cholangitis: cholangiographic appearances 总被引:1,自引:0,他引:1
MacCarty RL; LaRusso NF; May GR; Bender CE; Wiesner RH; King JE; Coffey RJ 《Radiology》1985,156(1):43-46
Cholangiograms from 104 patients (and serial cholangiograms in 66 patients) with primary sclerosing cholangitis (PSC) were reviewed. In 13 patients the additional diagnosis of cholangiocarcinoma was made at biopsy or autopsy. Cholangiograms from patients with both PSC and carcinoma were compared with cholangiograms from patients with PSC alone. Marked dilatation of ducts or ductal segments (100% vs. 24%) and the appearance of a polypoid mass (46% vs. 7%) were common findings in the group of patients whose disease was complicated by malignancy. In the malignant group, polypoid masses were larger, measuring 1 cm or greater in diameter. On serial cholangiograms, four of 15 patients with progressive stricture formation and four of five with progressive ductal dilatation proved to have carcinomas. The frequent occurrence of bile duct carcinoma as a complication of PSC in this group of patients indicates that PSC has a strong tendency to undergo malignant degeneration. Cholangiographic findings which suggest malignant degeneration include markedly dilated ducts or ductal segments, presence of a polypoid mass 1 cm or greater in diameter, and progressive stricture formation or ductal dilatation. 相似文献
599.
The medical records of 66 patients who underwent evaluation for possible deep venous thrombosis (DVT) by means of gradient-echo (GRE) magnetic resonance (MR) imaging were reviewed. Confirmatory venograms were obtained in 26 patients; in the other 40, the accuracy of GRE MR imaging was assessed by means of clinical follow-up, which ranged from 1 to 23 months (mean, 7.7 months). Findings in GRE MR images were negative in 42 patients (64%) and positive in 24 patients (36%). In patients who underwent confirmatory venography, the sensitivity of GRE MR imaging was 100% and the specificity was 92.9%. No patient with a negative GRE MR study developed DVT or pulmonary emboli during the follow-up period. Although seven patients in this group died, the single autopsy showed no evidence of pulmonary embolism, and no clinical evidence existed to suggest that pulmonary embolism was the cause of death in any of the other six patients. It is concluded that GRE MR imaging is an accurate, noninvasive means of detecting DVT. 相似文献
600.