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排序方式: 共有1278条查询结果,搜索用时 15 毫秒
31.
32.
Central thrombi in pulmonary arterial hypertension detected by MR imaging   总被引:1,自引:0,他引:1  
Fisher  MR; Higgins  CB 《Radiology》1986,158(1):223-226
Differentiation of thrombi from slow flow in the pulmonary arteries, sometimes observed in the presence of pulmonary arterial hypertension, can be equivocal. Magnetic resonance (MR) imaging was performed in a patient with chronic pulmonary thromboembolism and pulmonary arterial hypertension using an electrocardiographically gated technique that allowed visualization of the pulmonary arteries at the end of diastole and multiple times during systole. These images were compared with those of a patient with primary pulmonary hypertension and those of healthy subjects. Thrombi were discrete structures, seen throughout the cardiac cycle on both the first and second spin-echo images, and decreased in signal intensity on the second image. Slow flow increased in signal intensity and changed in structure during the cardiac cycle and was seen best on the second image. MR may play an important role in excluding large central thrombi as the cause of pulmonary arterial hypertension. It is a noninvasive method for defining pulmonary arterial wall thickness and for direct visualization of chronic pulmonary thrombus.  相似文献   
33.
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   
34.
Checketts  MR; Wildsmith  JAW 《CEACCP》2004,4(2):48-51
The last few years have seen increasing concerns among anaesthetistsabout the risks of pharmacological prophylaxis for thromboembolicdisease. Increased bleeding during or after surgery is one concern,but of greater significance is the possibility of an increasedpredisposition to haematoma formation when regional block isused. Most of the recent consideration of this problem has beenin relation to vertebral canal haematoma formation after centralnerve block. Some thought must be given also to the possibilityof haematoma formation after peripheral techniques when thetarget nerve is deeply placed so that pressure cannot be usedto control bleeding after needle insertion. However, this reviewwill be focused on vertebral canal haematoma.  相似文献   
35.
It is highly recommended to conduct a prophylactic check for any dental problems on patients who suffer from leukaemia before chemotherapy begins. Bacteraemia caused by oral microflora may be very dangerous for patients with haematological malignancies. However, it should be noted that the prophylactic process itself might bring about life-threatening complications if there is only a short interval between dental treatment and the beginning of chemotherapy, or if the dental treatment is too aggressive. We present a case where this prophylactic procedure produced life-threatening complications for a patient with acute myeloid leukaemia.  相似文献   
36.
Background Subcutaneous zygomycosis is an uncommon condition observed in tropics. Few series have been published, particularly from the northern regions of India. Objectives The aim of this study was to describe clinical, investigative and therapeutic details in subcutaneous zygomycosis observed in two teaching hospitals in Delhi. Patients and methods Ten patients seen over a period of 10 years (1999–2009) form the material for this report. Results There were four children and six adults. In four children, the presentation was a subcutaneous localized mass or gradually spreading plaque. In the others, it was observed over nasal region of face, spreading inward into mucosal sites and paranasal sinuses, and outward to the contiguous areas. Regional lymphadenopathy was present in two with facial lesions. Majority showed a granulomatous infiltrate with admixture of other cells, mainly eosinophils. Aseptate or poorly septate hyphae were observed in seven. In one patient in whom no hyphae were observed, there was dense perivascular inflammation. Organisms were cultured from four patients, Basidiobolus ranarum in two and Syncephalastrum racemosum in two. The main therapy used was a saturated solution of potassium iodide (KI). Four received only KI of which two attained cure after 3 months and 9 months respectively, and the other two showed signs of regression. In one boy subsidence was associated with reduced circumference of thigh. Ketoconazole or itraconazole was given with KI to hasten regression when response was slow or there were side‐effects to KI. Conclusion Awareness and early recognition will prevent disfigurement produced by advanced disease, misdiagnosis and unnecessary surgical intervention.  相似文献   
37.
Background

Weight regain (WR) and insufficient weight loss (IWL) after sleeve gastrectomy (SG) are challenging issues. This study aimed to evaluate the predictors of WR and IWL after SG.

Methods

In this retrospective analytical study, 568 patients who underwent SG at Hazrat-e Rasool General Hospital, Tehran, Iran, between January 2015 and April 2022 were evaluated. A total of 333 patients were included. WR and IWL were evaluated by multiple criteria such as a BMI of > 35 kg/m2, an increase in BMI of > 5 kg/m2 above nadir, an increase in weight of > 10 kg above nadir, percentage of excess weight loss (%EWL) < 50% at 18 months, an increase in weight of > 25% of EWL from nadir at 36 months, and percentage of total weight loss (%TWL) < 20% at 36 months. All participants were followed up for 36 months.

Result

The univariate analysis showed that preoperative BMI, obstructive sleep apnea, metformin consumption, and grades 2 and 3 fatty liver disease were associated with WR and IWL (P < 0.05). WR or IWL incidence varied (0–19.3%) based on different definitions. The multivariate analysis showed that a preoperative BMI of > 45 kg/m2 [odds ratioAdjusted (ORAdj) 1.77, 95% CI: 1.12–4.11, P = 0.038] and metformin consumption [ORAdj: 0.48, 95% CI: 0.19–0.78, P = 0.001] were associated with WR and IWL after SG, regardless of the definition of WR or IWL.

Conclusion

This study showed that preoperative BMI of > 45 kg/m2, obstructive sleep apnea, metformin consumption, and grades 2 and 3 of fatty liver disease were associated with WR or IWL.

Graphical abstract
  相似文献   
38.
目的探讨敏感性编码技术(SENSE)前瞻性门控螺旋相位对比MR检查序列在儿童与成人先天性心脏病检查的可行性。材料与方法当地伦理委员会批准该项研究,所有  相似文献   
39.
目的采用心脏MR(CMR)前瞻性研究冠状动脉斑块对心肌缺血的预测价值。方法 52例行冠状动脉造影(CA)后评定为可疑冠心病(CAD)的病人进行了CMR和  相似文献   
40.
Sickle cell disease: imaging of cerebrovascular complications   总被引:3,自引:0,他引:3  
Moran  CJ; Siegel  MJ; DeBaun  MR 《Radiology》1998,206(2):311
  相似文献   
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