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1.
Malignant transformation of a benign Warthin's tumour (adenolymphoma) is extremely rare. The light microscopic and ultrastructural features of an adenocarcinoma arising in a Warthin's tumour in the parotid gland are described. Light microscopy demonstrated a transition zone from the benign to the malignant component, and the malignant cells revealed oncocytic features by both light- and electronmicroscopy.  相似文献   
2.
OBJECTIVE: We sought to optimize sclerotherapy of the greater saphenous vein (GSV) by targeted application of foamed sclerosant by using a catheter. METHODS: We designed a new double-lumen catheter that is inserted into the GSV. Via one lumen, a balloon at the tip of the catheter can be inflated to stop the blood flow. Via the second lumen, the sclerosing agent can be injected and aspirated. This method enabled us to perform a targeted application of the sclerosing agent [catheter-assisted vein sclerotherapy (KAVS)]. In an open study, outpatients suffering from varicosis of the GSV received a foam sclerotherapy under ultrasound guidance, using the newly developed KAVS catheter. RESULTS: Thirty patients with an insufficiency (reflux) of the GSV were treated with the newly developed KAVS method using foamed polidocanol. The intervention was well tolerated in all patients without the occurrence of serious side effects. In 27 of the 30 treated patients (90%), we found a closure of the GSV at control visits 6 weeks, 3 months, and 6 months after treatment. CONCLUSIONS: The KAVS method represents a feasible approach for sclerotherapy of the GSV. The efficiency and treatment modalities need to be explored in further studies.  相似文献   
3.
Identification of αβ and γδ T Cell Receptor-Positive Cells   总被引:1,自引:0,他引:1  
Two lineages of T lymphocytes bearing the CD3 antigen can be defined on the basis of the nature of the heterodimeric receptor chain (alpha beta or gamma delta T cell receptor (TCR) expressed. Precise identification of alpha beta and gamma delta TCR+ cells is essential when studying the tissue distribution and function of these different T cells. In immunofluorescence studies gamma delta TCR+ cells have been identified as CD3+WT-31- or CD3+CD4-CD8- cells. However, this may not be the optimal procedure because gamma delta TCR+ cells are weakly WT-31+, and some are CD8+. The aim of this study was to evaluate a panel of monoclonal antibodies (MoAb) directed against different chains of the TCR-T3 complex for a more precise identification of alpha beta+ and gamma delta TCR+ cells in flow cytometric studies. We found that the MoAb anti-Ti-gamma A and delta-TCS-1, recognizing the TCR-gamma and the TCR-delta chain respectively, only reacted with a subpopulation of gamma delta TCR+ cells, whereas another TCR-delta chain recognizing MoAb anti-TCR-delta 1 reacted with all gamma delta TCR+ cells. All MoAb reported to belong to the CD3 group reacted with both alpha beta TCR+ and gamma delta TCR+ cells as expected. Our results indicate that all gamma delta TCR+ cells can be identified with the MoAb anti-TCR-delta 1. Because no MoAb recognizing the TCR-alpha or TCR-beta chains at the cell surface of intact cells are yet available, we suggest that alpha beta TCR+ cells could be identified as CD3+ anti-TCR-delta 1-cells.  相似文献   
4.
We have measured haemodynamic changes and plasma concentrationsof catecholamines during sufentanil-nitrous oxide and fentanyl-nitrousoxide anaesthesia in a controlled, randomized, double-blindstudy of 20 geriatric patients (age 65–86 yr) undergoingmajor abdominal surgery. Fentanyl 7 µg kg–1 followedby infusion of 3 µg kg–1 h–1 was comparedwith sufentanil 1 µg kg–1 followed by 0.4 µgkg–1 h–1. The opioid was supplemented with 60–67%nitrous oxide in oxygen. Haemodynamic changes, plasma concentrationsof catecholamines (by high pressure liquid chromatography) andopioids (by radio-immunoassay), and myocardial lactate extractionwere measured in the awake state, and at defined times duringanaesthesia and surgery. Haemodynamic state was stable duringinduction and trachea/ intubation in both groups, while duringstressful operative periods there were increases in mean arterialpressure (17%in the fentanyl group; 11% in the sufentanil group),heart rate (fentanyl 20%, sufentanil 14%) and plasma concationsof catecholamines (adrenaline: fentanyl 316%, sufentanil 86%;noradrenaline: fentanyl 78%, sufentanil 186%) in both groups.Sufentanil was similar to fentanyl in attenuating the haemodynamicand hormonal responses to surgical stimulation. In two patientsin the fentanyl group and three in the sufentanil group, myocardiallactate production was observed temporarily, indicating myocardialischaemia caused by surgical stress. *Present address: Department of Anaesthesiology, Universityof Homburg, Oscar-Orth-Straße D-6650 Homburg/Saar, Germany Results presented in pan at the 11th Annual Meeting of the EuropeanAcademy of Anaesthesiologists, Bonn, August 31, 1989  相似文献   
5.
Venous access required both for blood sampling and for the delivery of medicines and nutrition is an integral element in the care of sick infants and children. Peripherally inserted central catheters (PICCs) have been shown to be a valuable alternative to traditional central venous devices in adults and neonates. However, the evidence may not extrapolate directly to older paediatric patients. In this study, we therefore review the indications, methods of insertion and complications of PICC lines for children beyond the neonatal age to provide clinical recommendations based on a search of the current literature. Although the literature is heterogeneous with few randomised studies, PICCs emerge as a safe and valuable option for intermediate‐ to long‐term central venous access in children both in and out of hospital. Insertion can often be performed in light or no sedation, with little risk of perioperative complications. Assisted visualisation, preferably with ultrasound, yields high rates of insertion success. With good catheter care, rates of mechanical, infectious and thrombotic complications are low and compare favourably with those of traditional central venous catheters. Even in the case of occlusion or infection, fibrinolytics and antibiotic locks often allow the catheter to be retained.  相似文献   
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Lymphangiogenesis is an important event in progression of colorectal cancer (CRC), and the estimated lymphatic vascular density (LVD) probably indicates facilitated lymphatic tumor cell invasion and metastasis. However, at what time point during tumor progression this process is triggered, is unclear. The aim of this study was twofold. Firstly, to examine LVD in paired samples of CRC tissue and normal mucosa with specific emphasis on possible difference in LVD between tumors stages II and III, and secondly, the expression of the lymphangiogenic growth factor fibroblast growth factor‐2 (FGF‐2). Eighteen patients were studied. Immunostaining for podoplanin was performed to highlight lymphatic vessels. FGF‐2 mRNA expression was determined by quantitative real‐time RT‐PCR, whereas protein expression was quantitatively assessed by densitometric analysis of Western blot signal intensity. The immunoblots were further validated by FGF‐2 immunostaining of histological sections. LVD was significantly increased in tumor tissue compared with the normal mucosa but no changes in LVD between stages II and III CRC was observed. FGF‐2 was found to be downregulated both at the mRNA and protein level in tumor tissues compared with normal mucosa. Lymphangiogenesis was triggered early in tumor development. An increased LVD was established before the tumor reached stage II. FGF‐2 was downregulated in tumor tissue. The importance of this finding remains unclear.  相似文献   
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