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991.
Incidence of human parvovirus B19 DNA detection in blood donors   总被引:2,自引:0,他引:2  
Summary. 1000 serum samples from blood donors were tested for human parvovirus B19 (B19) DNA by a nested PCR assay: six samples were positive for B19 DNA. The frequency was 1/167 (0-6%), considerably higher than previous surveys (0-004-0-03%). Five of the six samples were also positive for anti-B19 IgM, indicating an acute phase of infection. It is recommended to screen for B19 DNA in blood products to prevent transfusion mediated viral infection for those susceptible such as immunocompromised patients and pregnant women.  相似文献   
992.
993.
Aim: Because the procedure of balloon-occluded retrograde transvenous obliteration (B-RTO) causes extensive thrombosis of the major shunt that connects the spleen and gastric/renal venous systems, an increase in portal pressure is unavoidable. The aim of the present study was to assess the long-term outcome of B-RTO, including changes in esophageal varices. Methods: B-RTO was conducted in 22 patients with gastric varices, who were divided according to the severity of esophageal varices at baseline; there were no esophageal varices (n = 7), F(1) varices (n = 11), and F(2) varices (n = 4). The outcome measures included the development/worsening of esophageal varices after B-RTO and survival rates. Results: The cumulative bleeding-free probability for all 22 patients at 3 years after B-RTO was 100%. The overall 3-year survival was 94.4%. Seven patients who had no esophageal varices prior to B-RTO did not develop any after the procedure. Seven (63.6%) of the 11 patients with stage F(1) esophageal varices prior to B-RTO showed no changes in the varices after B-RTO, while two patients progressed to F(2) varices and two developed F(3) varices. The cumulative treatment-free probability of the esophageal varices at 24 months after B-RTO was 100% for patients without esophageal varices at baseline, 80.8% for patients with pre-existing F(1) varices, and 75% for those with pre-existing F(2) varices. Conclusion: Although the B-RTO procedure is considered useful for the treatment of gastric varices, changes in hemodynamics due to obliteration of this major shunt must be taken into account and observed closely.  相似文献   
994.
Bilateral coronary artery fistula constitutes an uncommon subgroup of coronary artery fistulas that may have a distinct embryologic origin. Coronary artery fistulas usually show a tortuous arrangement upon coronary angiography, but aneurysmal dilatation is rare. We report here an extremely rare case of coronary artery fistula originating from both coronary arteries, which showed multicystic aneurysmal dilatation.  相似文献   
995.
A 56-year-old Japanese man with hypertension presented with a 10 days history of high fever, right and left upper quadrant tenderness. An abdominal ultrasonography and computerized tomographic scan revealed a large collection in the right lobe of the liver that was consistent with an abscess. A drainage catheter was placed and purulent fluid was drained. Cultures of the fluid and blood were positive for a strain of ampicillin-resistant Klebsiella pneumoniae. Six days after admission, paraplegia and urinary retention were found. On the neurological examination, deep tendon reflexes of the lower extremities were absent bilaterally. Magnetic resonance imaging scan detected thoracic spinal epidural abscess and paraspinal abscess. He received the emergent decompressive laminectomy. Culture of surgical specimen grew ampicillin-resistant K. pneumoniae. The patient was treated with biapenem intravenously. Thereafter, clinical symptoms improved gradually and he was removed to the professional hospital to continue rehabilitation for gait disturbance on hospital day 147.  相似文献   
996.
Secretion of aldosterone from aldosterone-producing adenoma (APA) is to some degree under the control of ACTH and the suppressible effect of glucocorticoid on plasma aldosterone concentration (PAC) and blood pressure has been reported to be transient. We report a rare case of aldosteronism due to APA in which PAC and blood pressure were well controlled with small dose dexamethasone for over one year. No chimeric gene of glucocorticoid-remediable aldosteronism (GRA) was found in DNA of APA and leukocytes from peripheral blood and 17alpha-hydroxylase deficiency (17-OH-D) was ruled out by endocrinological examinations, this case indicates the possibility of an unknown mechanism of ACTH-dependent APA.  相似文献   
997.
The optimal combination of arterial grafts for quadruple coronary artery bypass is the bilateral internal mammary artery, the radial artery, and the gastroepiploic artery. Patients who underwent quadruple bypass in our hospital group between December 1995 and March 2001 were retrospectively analyzed to determine whether off-pump surgery (n = 27) provides better outcomes than conventional on-pump surgery (n = 51). Preoperative risk factors as well as the mean number of distal anastomoses (4.5 in the off-pump versus 4.8 in the on-pump patients) were not significantly different between the 2 groups. Postoperative recovery was significantly faster in the off-pump group than in the on-pump group (intubation time, 6.4 versus 16 hours; stay in intensive care unit, 2 versus 3 days; and postoperative hospital stay, 12.3 versus 15.8 days). Early stenosis-free graft patency rates did not differ significantly (90.3% versus 89.3%). No late cardiac events were observed in the off-pump group, while 4 occurred in the on-pump group. Quadruple arterial bypass without cardiopulmonary bypass is safe, and it allows faster recovery. The follow-up results of off-pump patients so far have been satisfactory.  相似文献   
998.
AIM: Nonalcoholic steatohepatitis (NASH) is a severe form of nonalcoholic fatty liver disease (NAFLD), and progresses to the end stage of liver disease. Biochemical markers of liver fibrosis are strongly associated with the degree of histological liver fibrosis in patients with chronic liver disease. However, data are few on the usefulness of markers in NAFLD patients. The aim of this study was to identify better noninvasive predictors of hepatic fibrosis, with special focus on markers of liver fibrosis, type VI collagen 7S domain and hyaluronic acid. METHODS: One hundred and twelve patients with histologically proven NAFLD were studied. RESULTS: The histological stage of NAFLD correlated with several clinical and biochemical variables, the extent of hepatic fibrosis and the markers of liver fibrosis were relatively strong associated. The best cutoff values to detect NASH were assessed by using receiver operating characteristic analysis: type VI collagen 75 domain ≥5.0 ng/mL, hyaluronic acid ≥43 ng/mL. Both markers had a high positive predictive value: type VI collagen 7S domain, 86% and hyaluronic acid, 92%. Diagnostic accuracies of these markers were evaluated to detect severe fibrosis. Both markers showed high negative predictive values: type VI collagen 7S domain (≥5.0 ng/mL), 84% and hyaluronic acid (≥50 ng/mL), 78%, and were significantly and independently associated with the presence of NASH or severe fibrosis by logistic regression analysis. CONCLUSION: Both markers of liver fibrosis are useful in discriminating NASH from fatty liver alone or patients with severe fibrosis from patients with non-severe fibrosis.  相似文献   
999.
The role of the renal nerve in influencing the hypothalamo-sympathetic nerve system to regulate the cardiovascular system was studied in normotensive Wistar and spontaneously hypertensive rats (SHR). Renal denervation attenuated pressor and sympathetic nerve responses to electrical stimulation of the hypothalamus without lowering the basal blood pressure at 48 hours after denervated operation. These findings suggest that renal denervation could inhibit the hypothalamo-sympathetic nerve system in normotensive rats. The development of hypertension in SHR was completely inhibited by renal denervation during 2 weeks of observation (from 7 to 9 weeks of age) without increasing water intake and urine volume. Pressor responses to intravenous injection of norepinephrine were not affected by renal denervation. The results show that the antihypertensive effect of renal denervation was not due to the changing of vascular reactivity. Pressor and sympathetic nerve responses to hypothalamic stimulation were strongly diminished in renal denervated rats. These results suggest that renal denervation strongly inhibited they hypothalamo-sympathetic nerve system. It is also suggested that the renal afferent nerve may facilitate the hypothalamo-sympathetic nerve system in regulating blood pressure and that this facilitation may contribute to the development of hypertension in SHR.  相似文献   
1000.
We present a case of esophageal carcinoma in which esophagectomy was not possible because of tuberculous fibrosing mediastinitis. A 77-year-old man was diagnosed with carcinoma of the thoracic esophagus and admitted to our hospital. Chest radiography on admission revealed no abnormality except pleural thickening of the pulmonary apices, suggesting a history of subclinical infection of tuberculous pleurisy. The patient underwent surgery with a curative intent. Thoracotomy revealed that the mediastinum had been replaced with dense fibrous tissues and was widely encased with laminar calcification. Esophagectomy was not performed because it was considered impossible to do so safely. Although diagnosis of fibrous mediastinitis was not made preoperatively, review of the preoperative computed tomographic scans revealed proliferation of mediastinal soft tissues that were associated with patchy and laminar calcifications. Tuberculous fibrosing mediastinitis is an uncommon but clinically important disease for physicians who are involved in the diagnosis and treatment of esophageal cancer.  相似文献   
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