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991.
992.
Because cardiomyocytes lose the ability to divide upon differentiation, myocardial failure is assumed to be generally irreversible. For terminal cardiac insufficiency, the potential for regenerative treatment by stem cells, especially embryonic stem (ES) cells, offers hope for the future. Recent studies showed that stem cells fuse spontaneously with cells remaining in damaged tissues, and restore tissue function. To imitate spontaneous fusion in vivo, we used polyethylene glycol (PEG) in vitro to fuse mouse ES cells and fetal cardiomyocytes and analyzed the cytochemical properties of the fused cells. Confocal laser scanning microscopy coupled with lipophilic dye labeling of the living cell membranes showed that there were fused cells of ES cells and cardiomyocytes after PEG treatment. By flow cytometry, the fusion efficiency between ES cells and cardiomyocytes was estimated to be about 45% of the total resulting cells. When green fluorescent protein (GFP)-expressing ES cells were fused with cardiomyocytes, the fused cells had immunoreactivity for GFP in their cytoplasm and cardiac troponin I in their myofibrils. Some of these cells also expressed proliferating cell nuclear antigen up to 11 days after fusion, the last time point examined. This study shows that PEG-induced fusions of mouse ES cells and cardiomyocytes have the cardiomyocyte phenotype and proliferation potential.  相似文献   
993.
994.
Two patients with testicular tumors whose serum alpha-fetoprotein (AFP) persisted to show an abnormally high concentration are reported. Case 1 : A 42-year-old male who had been suffering from chronic hepatitis, underwent left high orchiectomy for a left testicular tumor in 1998. Diagnosis was an authentic stage I seminoma. In 2002, chemotherapy was performed for a metastatic seminoma revealed as a solitary mass in the mediastinum by radiographic studies, and histologically confirmed to be a metastatic seminoma. Although lymph nodes were gradually reduced in size, the serum AFP and transaminase levels remained at an abnormally high concentration. The subfraction profile with lens culinaris hemagglutinin (LCA) revealed elevation of only peak 1 which implied that the chronic hepatitis was due to liver dysfunction. After a 10-month follow-up the levels of both AFP and transaminase decreased, and the patient was disease-free. Case 2: In 2002, a 30-year-old male underwent left high orchiectomy for a left testicular tumor, and histological examination revealed seminoma, immature and mature teratoma, embryonal carcinoma. The serum AFP was elevated to 45 ng/ml. Diagnosis was authentic stage I. After 2 courses of chemotherapy, the serum AFP remained at an abnormally high concentration. However, there were no new lesions. The serum AFP level was not elevated in any of the family members. The subfraction profile with LCA revealed elevation of only peak 1, which implied that there were no viable lesions. After a 24-month follow-up AFP was about 20 ng/ml and the patient was disease-free.  相似文献   
995.
Purely intraorbital arteriovenous fistulas (AVFs) are rare, and their clinical management is controversial. The authors successfully treated a patient with an intraorbital AVF by transvenous embolization alone. An accurate distinction between an arteriovenous malformation (AVM), which is characterized by the existence of a nidus, and an AVF, which has no nidus, is important and requires superselective ophthalmic artery angiography. Treatment of an intraorbital AVF by transvenous embolization can improve visual function.  相似文献   
996.
Coronary artery occlusion during off-pump coronary artery bypass grafting may lead to mechanical trauma of the arterial wall. My colleagues and I describe a safe coronary artery occlusion technique in off-pump bypass grafting that uses a new spring-equipped tourniquet, which enables precise adjustment of the least force necessary to occlude the coronary flow. This prevents snare-induced vessel wall damage.  相似文献   
997.
BACKGROUND: It is sometimes difficult to determine the extent of resection in patients with endobronchial carcinoma because preoperative white-light bronchoscopic (WLB) examination is not sensitive enough to examine the extent fully. Light-Induced Fluorescence Endoscopy (LIFE) is recognized as a useful modality for the diagnosis of early staged bronchial carcinoma, but there have been no reports of its significance in surgical treatment. We have studied the influence of LIFE upon the selection of surgical procedures or other treatments in patients with endobronchial carcinoma preoperatively. METHODS: Conventional WLB and LIFE were performed within 7 days of operation. Biopsy specimens were taken from the marginal regions of the areas that were suspicious for malignancy on LIFE examination and WLB. We decided the resection line before operation and kept the resected central margin 1 cm apart from the area revealed as suspicious by LIFE. RESULTS: From January 1999 to March 2003, 75 patients underwent LIFE. LIFE was performed to decide the surgical procedures for 12 patients (16.0%). Surgical therapy was performed in 8 (66.7%). LIFE findings dramatically changed the surgical procedures for 3 patients, lobectomy changed to sleeve lobectomy in 2 and laser therapy to segmentectomy in 1. LIFE revealed larger abnormal areas of bronchial cancer compared to WLB in 7 (58.3%). Conversely, WLB overestimated the extent of abnormal area in 1 (8.3%). WLB revealed the same cancer area as LIFE in 4. In all patients, the resected bronchial margins were cancer free intraoperatively and postoperatively. CONCLUSION: LIFE can be more sensitive than WLB and be more beneficial for judging the extent of neoplastic bronchial changes for some patients. LIFE may be a useful modality for the preoperative selection of surgical procedures, especially whether sleeve resection is needed or not, for some centrally located superficial endobronchial carcinoma.  相似文献   
998.
A 49-year-old man presented with fever and uremic symptoms such as general malaise, leg edema and decreased urine output. He was diagnosed as having infective endocarditis (IE) accompanied by renal failure. Although he had been receiving hemodialysis for a long time, renal function dramatically improved after heart valve replacement. This case suggests that uremia can develop as an initial manifestation of IE and removal of an infected heart valve can improve renal function despite persistent renal failure. From the perspective of recovery of renal function, early surgery should be considered in patients with renal failure following IE.  相似文献   
999.
Although it has been reported that chronic obstructive pulmonary disease (COPD) is frequently associated with systemic immune disturbances, negative impact of these disturbances on the increased prevalence of acute respiratory tract infections (aRTIs) has remained unclear. We evaluated circulating levels of interferon-gamma (IFN-gamma), soluble interleukin-2 receptor (sIL-2R), neopterin, and soluble intercellular adhesion molecule-1 (sICAM-1) in 35 clinically stable patients with COPD and in 22 age-matched healthy controls, since these molecules are considered to reflect the in vivo status of systemic cell-mediated immunity (CMI). We found that circulating levels of sIL-2R (1.52+/-1.25 vs. 0.97+/-0.48 ng/ml; P<0.05), neopterin (7.23+/-4.24 vs. 4.95+/-1.52 nmol/l; P<0.05), and sICAM-1 (665+/-302 vs. 328+/-164 ng/ml; P<0.0001), but not IFN-gamma (7.55+/-4.72 vs. 6.65+/-1.13 pg/ml; P=NS) were significantly higher in patients with COPD than in the controls. Importantly, follow-up study for 12 months demonstrated that patients in subgroup with relatively higher circulating levels of sIL-2R (2.20+/-1.44 ng/ml, n=18) had significantly higher risk of developing aRTIs (P=0.0204) than those in subgroup with relatively lower circulating levels of sIL-2R (0.80+/-0.23 ng/ml, n=17). These results may suggest that impaired systemic CMI observed in COPD patients is associated with the increased susceptibility to aRTIs in these patients.  相似文献   
1000.
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