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81.
口服Carvedilol治疗心力衰竭多中心研究(MOCHA)   总被引:1,自引:0,他引:1  
标题 Carvedilol对慢性心力衰竭患者左心室功能的改善和存活的提高呈剂量相关性作者 BristowMR,GilbertEM,AbrahamWT,等  Circulation1996,94:2807~2816  研究疾病:充血性心力衰竭。目的:对Carvedilol治疗慢性心力衰竭患者剂量-疗效特征进行评价。  设计:随机、双盲、安慰剂对照的多中心研究,剂量效应关系研究。病人资料:共345名心力衰竭患者,年龄18~85岁,左室射血分数≤0-35,心力衰竭症状时间≥3月,研究前所有患者必须用利…  相似文献   
82.
Volumetric rendering of MR images   总被引:1,自引:0,他引:1  
The authors developed new techniques for three-dimensional display of magnetic resonance (MR) images that preserve soft-tissue definition, are fully automatic, and work with routinely used section thicknesses. MR images are segmented, selectively enhanced, and displayed by means of a volumetric rendering algorithm. These techniques were used to illustrate normal anatomy of the brain, knee, and liver. Three-dimensional rendering of balanced spin-echo images shows the ventricles and extracerebral veins and of T1-weighted images, the sulci and gyri. The large hepatic and portal vessels can be seen with these enhancement techniques. Three-dimensional views of the knee reveal articular surfaces of the tibia and clearly depict menisci and posterior and anterior cruciate ligaments. These techniques make it possible to image multiple soft tissues simultaneously while preserving the detail contained in the original images. Three-dimensional presentation of complex, overlapping anatomic regions is helpful in surgical planning and should lead to improved diagnosis.  相似文献   
83.
84.
Pulmonary manifestations of AIDS: review of 106 episodes   总被引:9,自引:0,他引:9  
Suster  B; Akerman  M; Orenstein  M; Wax  MR 《Radiology》1986,161(1):87-93
We reviewed the clinical records and chest radiographs of all patients admitted to our institution between 1982 and 1984 who had pulmonary disease and who were later proved to have acquired immunodeficiency syndrome (AIDS) (95 patients). Diffuse parenchymal lung disease was the most common finding. These infiltrates were usually interstitial and caused by Pneumocystis carinii pneumonia or P. carinii combined with cytomegalovirus infection. Focal, multilobar, interstitial infiltrates were also often seen and usually caused by P. carinii or P. carinii and cytomegalovirus infections. Rarely, well-defined, multiple, interstitial nodules less than 10 mm in diameter were the only or predominant characteristic and were seen only in association with Mycobacterium tuberculosis or Cryptococcus neoformans infections or Kaposi sarcoma. Hilar or mediastinal adenopathy occurred in 17 of the 21 patients with M. tuberculosis or C. neoformans infections. In contrast, only 4% of patients with P. carinii infections presented with these findings. We also found that hilar or mediastinal adenopathy was not significantly associated with peripheral adenopathy. Lung cavitation, pleural effusion, or a normal chest radiograph was uncommon.  相似文献   
85.
AIM: To determine whether increased bilirubin production, reflected by blood carboxyhaemoglobin (COHb) values, is responsible for hyperbilirubinaemia in cases of Down's syndrome with no obvious cause for excessive jaundice. METHODS: Blood was sampled on the third day of life for COHb, total haemoglobin (tHb), and serum total bilirubin, from 19 consecutively born neonates with Down's syndrome (a subset of 34 term babies), who had developed hyperbilirubinaemia (serum bilirubin >/= 256 micromol), and from 32 term controls. COHb, measured by gas chromatography, was corrected for inspired CO (COHbc) and expressed as a percentage of tHb. RESULTS: Significantly more of the Down's syndrome subset developed hyperbilirubinaemia than the controls (10/19 (52%) vs 7/32 (22%), relative risk 2.4, 95% confidence intervals (CI) 1.10 to 5.26). Third day serum bilirubin values (mean (SD)) were higher in the Down's syndrome neonates than in controls (214 +- 63 micromol/l vs 172 +- 54 micromol/l, respectively, p=0.015). Mean (SD) COHbc values were significantly higher in the Down's syndrome neonates than in controls (0.92 +- 0. 24% vs 0.63 +- 0.17%; p<0.0001). However, Down's syndrome neonates who became hyperbilirubinaemic had similar COHbc values to those who did not (0.87 +- 0.26% and 0.95 +- 0.23%, respectively). These values contrast with those of the controls, in whom a significant increase in COHbc was associated with hyperbilirubinaemia (0.74 +- 0. 15% vs 0.60 +- 0.16%, respectively; p<0.05). tHb values were similar in both groups. CONCLUSIONS: Down's syndrome neonates had a greater risk of hyperbilirubinaemia, and higher COHbc values, than controls. However, excessive bilirubin production could not be exclusively responsible for the hyperbilirubinaemia. By inference, decreased bilirubin elimination probably plays a greater part in its pathogenesis than in controls. Down's syndrome neonates may have abnormal erythropoiesis, leading to increased haem turnover.  相似文献   
86.
Ascitic fluid opacification on delayed intravenous contrast computed tomography scans was observed in eight consecutive patients imaged. This apparently common phenomenon may alter both the sensitivity and the specificity of ascitic fluid detection. It may also serve as a diagnostic aid by making nonascitic intra-abdominal fluid collections (ie, pseudocyst and cystic tumor) more apparent.  相似文献   
87.
The nuclear medicine bleeding scan is frequently insufficient to locate sites of bleeding precisely, in spite of its great sensitivity. A small, hand-held Geiger-Müller counter, placed directly on exposed intestine in the operating room, enables precise location of the probable bleeding site. In three patients, the technique allowed a minimal amount of intestine to be resected, distinguished between large- and small-intestinal hemorrhage, and eliminated other foci as sites of bleeding.  相似文献   
88.
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   
89.
Background  Pemphigus foliaceus is an autoimmune blistering skin disease characterized by the production of pathogenic IgG autoantibodies directed against desmoglein 1.
Aim  To determine the prevalence of anti-desmoglein 1 antibodies in healthy subjects and their distribution in the different regions of Tunisia and to better identify endemic areas of pemphigus foliaceus.
Methods  We tested, by enzyme-linked immunoserbent assay, sera of 270 normal subjects recruited from different Tunisian areas and 203 related healthy relatives to 90 Tunisian pemphigus foliaceus patients.
Results  Seventy-six patients (84.4%), 20 healthy controls (7.4%), and 32 relatives (15.76%) had anti-desmoglein 1 antibodies. In southern regions where pemphigus foliaceus is associated with a significant sex ratio imbalance (9 female : 1 male in the south vs. 2.3 : 1 in the north) and a lower mean age of disease onset (33.5 in the south vs. 45 years in the north), a higher prevalence of anti-desmoglein 1 antibodies in healthy controls was observed (9.23% vs. 5.71% in the north). Interestingly, the highest prevalence of anti-desmoglein 1 antibodies in healthy relatives (up to 22%) was observed in the most rural southern localities. More than half anti-desmoglein 1–positive healthy controls were living in rural conditions with farming as occupation, which suggests that this activity may expose the subjects to particular environmental conditions.
Conclusion  These results show that the endemic features of Tunisian pemphigus foliaceus are focused in these southern areas more than in other areas and that both environmental and genetic factors contribute to the disease.

Conflicts of interest


None declared.  相似文献   
90.
Thromboxane B2 may be a mediator of neonatal persistent pulmonary hypertension. Elevated levels of plasma thromboxane and prostacyclin have been described previously in hypoxic newborn infants with neonatal pulmonary hypertension. We measured serial plasma levels of thromboxane B2 and 6-keto-prostaglandin F1 alpha (stable metabolite of prostacyclin) in 21 newborn infants with severe respiratory failure and pulmonary hypertension who required extracorporeal membrane oxygenation support. We sought to study (1) the evolution of plasma prostanoids in pulmonary hypertensive infants treated with extracorporeal membrane oxygenation and (2) whether different pulmonary hypertensive diagnostic subgroups have distinctive prostanoid profiles. Our data indicated that infants with meconium aspiration had significantly lower levels of plasma thromboxane B2 and 6-keto-prostaglandin F1 alpha while receiving extracorporeal membrane oxygenation than did infants with persistent pulmonary hypertension but no meconium aspiration. Levels of all infants decreased progressively as extracorporeal membrane oxygenation support continued.  相似文献   
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