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51.
The choice of a contrast agent for pulmonary angiography has important implications for patient comfort, image quality, and perhaps the safety of the procedure, particularly for "high-risk" patients. In a prospective study the nonionic, low-osmolality agent iopamidol eliminated the problem of image degradation due to coughing, and patients showed excellent tolerance for it. However, pressure measurements obtained within 3-5 minutes of injection of iopamidol and diatrizoate sodium meglumine 76% showed no significant difference in the hemodynamic effects of the two contrast agents, either for normotensive or for pulmonary hypertensive patients. Contrary to a common presumption, pulmonary hypertension by itself did not appear to increase the risk of pulmonary angiography. The theoretic presumption of greater hemodynamic stability with low-osmolality contrast agents was not clinically evident in this trial with iopamidol. At present, enhanced patient comfort and improved image quality remain the only confirmed bases for choosing this contrast agent for pulmonary angiography.  相似文献   
52.
Introduction  Malignant intracerebral nerve sheath tumor (MINST) is extremely rare and the origin is still unclear. The authors present the clinical, radiological, and pathological features of a malignant intracerebral giant nerve sheath tumor. Case report  A giant tumor in the right frontotemporoparietal lobes causing a midline shift was detected in a 14-month-old girl who presented with developmental delay, vomiting, and lethargy. The physical examination was consistent with neurofibromatosis type 1 (NF-1). Subtotal resection was performed and the histopathological examination revealed the diagnosis of MINST. Discussion  There are only six cases of malignant intracerebral nerve sheath tumor in the literature. The presented case is the youngest and the occurrence of MINST in a 14-month-old girl may support the hypothesis of multipotent mesenchymal stem cell origin; however, the tumors which arise from multipotent mesenchymal stem cells may be seen in later stages of life. Another important feature of the presented case is the occurrence of MINST in NF-1. Conclusion  MINSTs are extremely rare tumors with unknown origin. The location, the degree, and the size of the tumor and the general condition of the patient are prognostic factors in MINSTs, like in other malignant tumors.  相似文献   
53.
Cor triatriatum sinister (CTS) is a rare congenital cardiac anomaly in which a fibromuscular membrane divides the atrium into two chambers. As CTS can occur as an isolated anomaly, it is frequently associated with other cardiac anomalies. Although symptoms are usually encountered in infancy, CTS may rarely present in adulthood when the membrane contains large fenestration or other escape drainage exists. We herein, present an 82‐year‐old patient with a typical late diagnosis of asymptomatic CTS.  相似文献   
54.
The possibility of exercise-induced myocardial ischemia due to mitral valve prolapse (MVP) in the absence of coronary artery disease was evaluated with single-photon emission computed tomographic analysis using thallium-201 and technetium-99m sestamibi in 72 patients with MVP. Exercise electrocardiography was positive in 5 patients (8%), but single-photon emission computed tomography was found to be normal in all patients, and exercise-induced chest pain, electrocardiographic changes, and arrhythmias were found not to be related to myocardial ischemia in patients with MVP.  相似文献   
55.
The effects of statins have been investigated mostly in hyperlipidemic states so far. We analysed blood cholesterol, triglyceride, albumin, fibrinogen and gammaglobulin levels, haematocrite, hemoglobin, erythrocyte, leukocyte and platelet counts, blood and plasma viscosity and erythrocyte rigidity in 12 rabbits fed on a normal diet (chow) which were given 1 mg/kg/day atorvastatin for 4 weeks. Compared to the baseline levels, erythrocyte rigidity (k=0.12+/-0.05 vs. k=0.7+/-0.02) and gammaglobulin levels (1.03+/-0.23 g/dl vs. 0.78+/-0.27 g/dl) decreased significantly (p=0.008 and p=0.025, respectively). Blood lipids, hematological variables, blood and plasma viscosity did not change statistically. Our findings imply that in a normolipemic state, statins given in low doses may improve erythrocyte rigidity without altering blood lipids in short term. Decreased plasma gammaglobulin levels may be reflecting their immunomodulatory effects.  相似文献   
56.
OBJECTIVE

We analyzed the results of intravenous thrombolytic treatment under transesophageal echocardiographic (TEE) guidance in prosthetic valve thrombosis.

BACKGROUND

Thrombotic occlusion of prosthetic valves continues to be an uncommon but serious complication. Intravenous thrombolytic treatment has been proposed as an alternative to surgical intervention.

METHODS

In a four-year period, 32 symptomatic patients with prosthetic valve related thrombosis underwent 54 thrombolytic treatment sessions for the treatment of 36 distinct episodes. All patients had low international normalized ratio values at the presentation. Transesophageal echocardiography was performed at baseline and repeated after each thrombolytic treatment session (total 98 TEE examinations). Streptokinase was used as the initial agent with a repeat dose given within 24 h when necessary. Recurrent thrombosis was treated either with tissue plasminogen activator or urokinase.

RESULTS

The initial success after first dose was only 53% (17/32) but increased up to 88% (28/32) after repeated thrombolytic sessions upon documentation of suboptimal results on TEE examination (p < 0.01). In addition, four asymptomatic patients with large thrombi were also successfully treated with single infusion. The TEE characteristics of thrombus correlated with clinical presentation and response to lytics. Success was achieved with single lytic infusion in 40% of the obstructive thrombi as compared with 75% of the nonobstructive ones (p < 0.05). The success rates of lytic treatment were similar for mitral versus aortic valves, and for tilting disk versus bileaflet valves. Rapid (3 h) and slow (15 to 24 h) infusion of streptokinase resulted in similar success rates. However, major complications (three patients) occurred only in the rapid infusion group.

CONCLUSION

In patients with prosthetic valve thrombosis, intravenous slow infusion thrombolysis given in discrete, successive sessions guided by serial TEE and transthoracic echocardiography can be achieved with a low risk of complications and a high rate of success.  相似文献   

57.

Introduction

Reoperative parathyroidectomy is required when there is persistent or recurrent hyperparathyroidism following the initial surgery (at least 5% of parathyroidectomies nationally). By convention, ‘persistent disease’ is defined as the situation where the patient has not been cured by the first operation. The term ‘recurrent hyperparathyroidism’ is used when the patient was confirmed to be biochemically cured for six months from the first operation but has hyperparathyroidism after this date. Reoperative surgery is associated with higher rates of postoperative complications as well as a greater rate of failure to cure. The aim of our study was to review our departmental experience of reoperative parathyroidectomy, with a view to identify patterns of disease persistence and recurrence.

Methods

Using a departmental database, patients were identified who had undergone reoperative parathyroidectomy between 2006 and 2014. All the pre, intra and postoperative information was documented including the operative note so as to record the location of the abnormal parathyroid gland found at reoperation.

Results

Almost two-thirds (63%) of patients had negative, equivocal or discordant conventional imaging so secondary investigative tools were required frequently. The majority of abnormal glands were found in eutopic locations. The most common locations for ectopic glands were intrathyroidal, mediastinal and intrathymic. A third (33%) of the patients had multigland disease and over a quarter (28%) had coexisting thyroid disease.

Conclusions

Persistent hyperparathyroidism represents a challenging patient subgroup for which access to all radiological modalities and intraoperative parathyroid hormone monitoring are required. Patient selection for reintervention is a key determinant in the reoperation cure rate.  相似文献   
58.
59.
Acute effect of cigarette smoking on heart rate variability   总被引:2,自引:0,他引:2  
Acute cigarette smoking enhances adrenergic activity and thus may be associated with hemodynamic changes in the cardiovascular system. In this study, the acute effect of cigarette smoking on heart rate variability (HRV) was studied. Fifteen subjects were included in the study. Time domain (the mean R-R interval, the standard deviation of R-R interval, and the root mean square of successive R-R interval differences) and frequency domain (high-frequency, low-frequency ratio, and low-frequency/high-frequency ratio) parameters of HRV were obtained from all participants for each 5-minute segment: 5 minutes before and 5, 10, 15, 20, 25, and 30 minutes after smoking a cigarette. The mean R-R interval, the standard deviation of R-R interval, and the root mean square of successive R-R interval differences significantly decreased within the first 5-minute period compared with baseline, and then the standard deviation of R-R interval increased within the 20- to 30-minute period. The low-frequency high-frequency ratio significantly decreased within the first 5 minutes after smoking and then remained unchanged throughout the study period. Similarly, low-frequency and high-frequency power increased within the first 5 minutes compared with baseline. Acute cigarette smoking alters HRV parameters, particularly within the first 5 to 10 minutes after smoking.  相似文献   
60.
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