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961.
Kaviani A Ataie-Fashtami L Fateh M Sheikhbahaee N Ghodsi M Zand N Djavid GE 《Lasers in surgery and medicine》2005,36(5):377-382
BACKGROUND AND OBJECTIVES: We aimed to treat different pathologic types of basal cell carcinomas (BCCs) using photodynamic therapy (PDT). STUDY DESIGN/MATERIALS AND METHODS: Thirty lesions in six patients underwent PDT. The photosensitizer used was Photoheme, a hematoporphyrin derivative IX. It was injected intravenously at the dose of 2-3.25 mg/kg. After 24 hours, the lesions were illuminated by laser light (lambda = 632 nm, light exposure dose = 100-200 J/cm2). Lesions were evaluated pre and post-operatively and at follow-up sessions (of up to 6 months). RESULTS: After a single session of PDT, the average response rate in different histopathologic kinds of basal cell carcinoma (e.g., ulcerative, superficial, nodular, and pigmented forms) were 100%, 62%, 90%, and 14%, respectively. In patients who responded completely, the cosmetic results were excellent and there were no recurrence at 6th month of follow-up. CONCLUSION: Although PDT seems to be an effective treatment modality for superficial, ulcerative, and nodular BCCs, it is not recommended for pigmented lesions. 相似文献
962.
Osman F Ahmad RA Davis RC Connolly DL Cadigan PJ 《Pacing and clinical electrophysiology : PACE》2005,28(5):474-475
The present case report describes a 54-year-old woman with recurrent syncope of undetermined etiology. Despite several cardiological and neurological investigations, no firm diagnosis was established until an insertable loop recorder (REVEAL Plus Model 9526, Medtronic Inc., Minneapolis, MN, USA) revealed muscle twitch artifact secondary to a seizure disorder. 相似文献
963.
We and others have previously reported that thymic epithelial cells produce glucocorticoids (GCs). In vitro studies have also suggested that thymic-derived GCs play a role in the development of thymocytes. However, until now it has not yet been established whether thymic-derived GCs play a role in thymopoiesis in vivo. To investigate this, we conditionally overexpressed the GC receptor (GR) in thymocytes using transgenic mice with a tetracycline-inducible expression system. The influence of systemic GCs was excluded by adrenalectomizing the transgenic mice before the GR induction. Conditional expression of transgenic GR in the thymocytes of adrenalectomized transgenic mice led to a decrease in the thymocyte number. This was associated with increased thymocyte apoptosis. The effect of thymic-derived GCs on the thymocytes was confirmed after transgenic GR induction in a thymic organ culture system. Finally, the GR antagonist RU486 increased thymocyte number in adrenalectomized mice in vivo and prevented a reduction in thymocyte number in thymic organ culture after transgenic GR induction. These observations further confirmed a role for the thymic-derived GCs in regulating thymocyte homeostasis in vivo. 相似文献
964.
965.
The first successful removal of an epicardial cyst is reported. Evidence is presented to demonstrate that the cyst developed as a result of an abnormality occurring within the first five weeks of fetal life. 相似文献
966.
To further explore the usefulness of technetium 99m pyrophosphate (99mTc-PYP) myocardial imaging and test its validity in the diagnosis of acute myocardial infarction, 99mTc-PYP myocardial scintigrams were performed in 50 patients. Out of 28 patients with acute myocardial infarction, myocardial scintigrams demonstrated localized activity in the 15 patients with transmural, and diffuse activity in the 13 patients with subendocardial myocardial infarction. Twenty-two patients with significant coronary artery disease documented by coronary angiography but without acute myocardial infarction were also studied. Nine of ten patients with clinical evidence of left ventricular aneurysm from previous myocardial infarction and definite left ventricular dyskinesis had positive scintigrams with activity localized to the site of the wall motion abnormality. Two of five patients without definite aneurysm but with left ventricular akinesis also had localized uptake in the involved area of the left ventricle. Seven patients with normal left ventricular wall motion had negative scintigrams. These findings suggest caution in interpreting positive 99mTc-PYP scintigrams as being indicative of acute myocardial infarction when evidence of a left ventricular aneurysm is also present. 相似文献
967.
Two cases of strangulation of the heart following left intrapericardial pneumonectomy are described. The condition presents in the immediate post-operative period by sudden fall of blood pressure associated with a high central venous pressure. The diagnosis is usually made by the characteristic radiographic appearances. Actual strangulation of the ventricles is more common on the left side and can lead to irreversible damage in a short time. The predisposing and precipitating factors are discussed with special reference to prevention. Treatment of the established case is by emergency thoracotomy and reduction of the herniated heart. Recurrence is prevented by repairing the defect or wide excision of the pericardium. 相似文献
968.
E R Fisher T S Danowski U Ahmad P Breslau S Nolan T Stephan 《Archives of pathology》1975,99(11):607-610
Biopsy specimens of skeletal muscle from a family that had three female siblings with clinical features of recessive-type myotonia congenita were examined by light and electron microscopy. Fibers examined by the former technique appeared normal. Although some variation in size and shape of mitochondria and sarcomere fragmentation were focally observed by electron microscopy in affected members, they were also encounted in those without clinical manifestations. Importantly, no changes in sarcolemma, sarcoplasmic reticulum, or transverse tubular system were encountered. Capillary basement membrane thickness was within normal limits. The evidence strongly suggests that myotonia congenita represents an entity distinct from myotonia dystrophica and that its pathogenesis may be related to a biochemical rather than ultrastructal aberration. 相似文献
969.
970.
Nasal glioma is a rare benign tumor that usually occurs during infancy. We report a case of nasal glioma in a 6-month-old boy in which the histomorphologic features resembled those of an anaplastic astrocytoma. 相似文献