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81.
The effect of alpha-tocopherol and its derivatives on viability and growth of attached cells culture: human epithelioid carcinoma of cervix HeLa-S3K and human cervical carcinoma cell line C-4-1 according to protein content and level of alkaline phosphatase, as well to unattached cells: human acute leukemia cell cultures CEM-C-1 and CEM-C-7 according to the amount of viable cells in suspension has been studied. It has been shown that alpha-tocopherol acetate and tocopherol maintain the viability of cells, while the derivatives of tocopherol with shorted side chain considerably inhibit growth of researched cultures, alpha-tocopherol with lacking side chain being most active among them.  相似文献   
82.
In order to study the functional development of a thymus in an experimental model, small pieces of adult rat thymic tissue were cultured for 9 days and implanted under the kidney capsule of littermates. The tissues were examined with a panel of antibodies raised against thymic and neural factors and neural crest cells at intervals from 5 to 13 days. At 5 days post-implantation, there were groups of L1+ cells within the implants that reacted with antibodies raised against neural and neural crest cell markers. L1+ cells were highly mitotic, rounded cells measuring 8.7 +/- 0.6 micrometer in diameter. Double immunostaining with different combinations of antibodies showed that 94% of the L1+ cells were also TH+, and many were HNK-1/NCAM+, PGP 9.5+, NGF+, chromogranin A+, VIP+, S100+, CGRP+, GAD+, and A2B5+. A few were also pan-cytokeratin+. These results indicate that these cells are derived from neural crest derived cells and belong to the neuroepithelial line of development. The L1+ cells were most numerous before nerves appeared (about Day 9) and reduced in number and extent as the thymus differentiated. The neural crest cells occasionally had long cytoplasmic extensions, but it was not possible to decide if they formed the nerves that appeared in the implants. Adult thymuses also contained a population of L1+ and HNK-1/NCAM+ cells, mainly in the subcapsular cortex, the septa, and the medulla. These cells could be a source of neural crest cells able to repopulate the implant. The adult thymus may always contain a reservoir of cells potentially capable of producing neuropeptides and transmitter factors required for thymic growth and regeneration.  相似文献   
83.
AIM: To investigate the effectiveness of superfrequent transesophageal left atrial stimulation (TLAS) and its combination with cordarone in management of atrial flutter (AF). MATERIALS AND METHODS: 650 patients with paroxysmal AF underwent TLAS. The paroxysm duration varied from 1 hour to 1 month. In 312 patients TLAS was performed prior to treatment with antiarrhythmic drugs (group 1), in 338 patients--after intravenous administration of cordarone (group 2). RESULTS: Superfrequent TLAS has restored sinus rhythm (SR) in 85(27.2%) and 169(50%) patients of groups 1 and 2, respectively (p < 0.001). TLAS promoted conversion of AF in atrial fibrillation (AFi) in 185(59.3%) and 159(47.1%) patients of groups 1 and 2, respectively (p < 0.01). Moreover, SR recovered 24-48 hours after TLAS in 87(27.9%) and 64(18.9%) patients of groups 1 and 2 respectively (p < 0.01). Sinus rhythm recovered in a total of 172(55.1%) and 233(69.0%) patients, AF was converted to AFi in a total of 88(31.4%) and 95(28.1%) patients (p > 0.05) of groups 1 and 2, respectively. TLAS was uneffective in 42(13.5%) and 10(2.9%) patients of groups 1 and 2, respectively. CONCLUSION: Superfrequent TLAS is a highly effective and non-invasive modality in the treatment of paroxysmal AF. It promotes recovery of SR. In some patients TLAS induces AFi which is more controllable by medication as regards the heart rate. Cordarone contributes to the response to TLAS in patients with paroxysmal AF.  相似文献   
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A comprehensive programme was developed for the treatment of uni- and bilateral retinoblastoma in children with due regard to the disease stage by the TNM system. The use of the current sources of teletherapy and cyclic polychemotherapy expanded indications for organ-saving therapy at most common stages. Treatment by the program was performed in 202 patients, including 125 children with unilateral damage and 77 with bilateral damage. An attempt made treat 140 (75%) children at the first stage. More than 70% of cases were diagnosed as having disease stage T3 in one or two stage, while such patients underwent ocular enucleation. A complete or partial (more than 50%) tumor regression without signs of its progression for 2 years or more was achieved in 62% of cases. At the first stage of therapy, conservative therapy insignificantly affected the children's longevity in uncomplicated cases, which is particularly important in bilateral involvement, while this preserved the organ of vision in more than half the patients (62%). Five-year survival was 92 and 82% in unilateral retinoblastoma surgically treated and untreated, 83 and 84%, respectively. Adequate multimodality treatment brought about low incidence rates of recurrence and metastasis (10%) in conservative therapy and 7.7% among all patients.  相似文献   
87.
Left ventricular myocardial contractility was found essential in dynamics of clinical IHD picture in patients on rehabilitation treatment at low mountain resorts. All the patients have previously undergone surgical myocardial revascularization. Patients with normal left ventricular myocardial contractility benefited most of all.  相似文献   
88.
The authors investigated the multi-step mechanism of healing after cardiomyoplasty, focusing on the process of angiogenesis. The authors contend that enhancement of angiogenesis and prevention of ischemia-reperfusion injuries immediately after muscle mobilization will be effective in improving cardiomyoplasty results. After cardiomyoplasty, autologous biologic glue (ABG) was administered between the latissimus dorsi muscle (LDM) and myocardium. By 2 months, a new pseudo interlayer was present that bridged the gap between the LDM and myocardium. Neovascularization was visible in the form of numerous small capillaries. Marked degeneration of the LDM was noted, possibly caused by muscle ischemia-reperfusion damage after mobilization. Pockets were created of ischemic and nonischemic LDM to test for angiogenesis. One was left free of ABG (control); one received ABG only; one received ABG and pyrrolostatin. Some of the capillaries were large and had erythrocytes inside. biopsy samples showed 9.4 +/- 1.9% of the sample was occupied by blood vessels (compared with 3.6 +/- 0.7% in control muscle). These preliminary studies prove the feasibility of the authors' concept and provide evidence that angiogenesis can accelerate the healing process and provide an organic bridge between the LDM and myocardium after cardiomyoplasty.  相似文献   
89.
Childhood leukemia (ICD 204-208 [1]) incidence rates in the different regions of Belarus are reported for a period before and after the Chernobyl accident (1982-1994). There are, at this point, no recognizable trends towards higher rates.  相似文献   
90.
Computed tomography (CT) was performed in 189 individuals: in 44 children of schizophrenic parents (high risk group, HRG), in 39 parents with schizophrenia or with schizophrenic disturbance, in 56 children with schizophrenia, in 50 children with consequences of early organic damages of central nervous system (mental retardation syndrome and generalized tic syndrome). The frequency of CT changes was equal in the mentioned groups but their character was quite different. The widening of brain's liquor system (89.7%), the signs of frontal and temporal atrophia (31%), foci of decreased density of cerebral brain's matter, closer in subcortical ganglia and periventricular zone, and different anomalies of brain were observed in HRG children.  相似文献   
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