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51.
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The activity of large dorsomedial protocerebral A2' neurosecretory neurons were investigated in late pupae of Tenebrio molitor L, which were exposed to a static magnetic field of 320 mT. Experimental groups were C: the control group which was kept at 5 meters from the magnet; CMF: pupae which were reared in control conditions and sacrificed on the eighth day of pupal stage (parents were kept in a magnetic field); and MF: pupae kept in a permanent magnetic field for eight days. Our results indicate the effects of a static magnetic field on the cytological characteristics and activity of large A2' neurosecretory neurons of Tenebrio molitor pupae.  相似文献   
53.
The role of macrophages acting as immunologic antitumor effectors and promoters of tumor growth are poorly understood as yet. We investigated the role of macrophage in model of concomitant immunity (CI), a phenomenon of secondary tumor rejection during the primary tumor growth. It has been shown that the period of CI weakening can coincide with appearance of tumor metastases. We used mammary carcinoma (MC) artificial lung metastases to evaluate the influence of macrophages from various period of CI on the development of metastases in mice. Our results indicated that macrophages are responsible for the late period of CI weakening and suppression. To investigate weather prostaglandins can mediate suppressive effect of macrophages we used experiments with indomethacin and we found that inhibition of prostaglandin E2 synthesis by indomethacin restored antimetastatic effect of concomitant immune macrophages.  相似文献   
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HPV infections are common and the presence of the same high-risk type in cervical specimens can be due to reinfection or persistence. Persistent infection is the most important predictor for development of cervical carcinoma. The aim of this study was to validate PCR-RFLP with two sets of primers: MY09/MY11 that amplify a fragment of L1 and P1/P2 that amplify a fragment of E1 ORF. PCR product of MY09/MY11 was digested with a set of 6 restriction enzymes (RE) and PCR product of P1/P2 with a set of 12 RE. Cervical samples from 110 women patients of the University Gynecologic Clinic CHC Zagreb were analyzed. There were 98 (89.1%) PCR positive samples detected with P1/P2 primers, and 94 (85.5%) PCR positive samples detected with MY09/MY11 primers. Seven HPV types were detected with P1/P2-RFLP technique and 17 with MY09/MY11-RFLP PCR positive samples amplified with both primer pairs agreed with each other in 82 samples; 16 samples were only positive with P1/P2 and 12 samples were only positive by MY09/MY11. HPV 16 was detected in 39 samples with MY09/11-RFLP, out of these two variants (two different patterns) were found with P1/P2 using Dde I, Hae III and Eco I. HPV 6 was detected in 9 samples with MY09/11-RFLP, out of these two variants were found with P1/P2 using HinfI. Combining these two PCR-RFLP methods subtypes of HPV 16 and HPV 6 were detected.  相似文献   
55.
An overexpression of cell adhesion molecules (CAMs) on the surface of endothelial cells is one of the first steps in a high glucose-mediated endothelial dysfunction in diabetic patients. The effect of insulin administration in the condition of elevated glucose concentration on the E-selectin, intracellular adhesion molecule-1 (ICAM-1) and vascular adhesion molecule-1 (VCAM-1) expression on human aortic endothelial cells (HAEC) was investigated. Cells were cultured for 4 h in a medium supplemented with homocysteine (7 pM) and different concentration of glucose (5.5, 8.0, 12.0 and 16.5 mM respectively) with or without insulin (1 mlU/mL) addition. Expression of CAMs was analysed by flow-cytometry using monoclonal antibodies. Controls were CAMs expression in the medium with a corresponding glucose concentration. Obtained results show that short-term exposure of HAECs to moderate high glucose concentrations results in increased expression of E-selectin (2-fold), VCAM-1 (3-fold) and ICAM-1 (47%). At the same time, HAEC grown with 12 mM glucose expressed lesser E-selectin and, more ICAM-1 (for 64%) and VCAM-1 (41%) molecules. 16.5 mM glucose decreased expression of all investigated adhesion molecules. Addition of insulin was not changed expression of CAMs in a medium with 5.5 mM glucose. In conditions of elevated glucose concentration (12 mM), addition of insulin significantly dropped E-selectin (27%) and increased VCAM-1 (23%) expression. In conclusion, moderate elevated glucose concentration increased expression of cell adhesion molecules on HAEC. Insulin administration in the mild hyperglycaemia reduces an expression of the proinflammatory adhesion molecule E-selectin which could contribute in deceleration of macrovascular complications development in diabetic patients.  相似文献   
56.
The efficient synthesis of new bis-substituted nitro-amidino, amino-amidino (10a, 10b13a, 13b) and previously prepared diamidino 2-phenyl-benzothiazoles (9a, 9b) is described. The compounds 11a and 11b were prepared by recently developed methodology of the key precursors in zwitterionic form 8a and 8b with 4-nitrobenzoylchloride in a very good yield (70%). All compounds except diamidino-substituted 2-phenylbenzothiazole 9a show exceptionally prominent tumor cell-growth inhibitory activity and cytotoxicity, whereby the special selectivity of amino-amidine 2-phenylbenzothiazole 12a towards MCF-7 and H 460 cells makes this compound a prospective lead compound that should be further evaluated in animal models. All in vivo tested compounds (12a, 12b, 13a and 13b) are absorbed from mice gastrointestinal system. LD50 are between 67.33 and 696.2 mg/kg body weight (OECD/EPA toxicity categories 2–3).  相似文献   
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There is a well-established role for reactive oxygen and nitrogen species, chronic inflammation and immune response in the pathogenesis of breast cancer. Complex interactions between breast cancer cells and surrounding blood vessels are prerequisites for cancer growth and invasion. Reports in the literature concerning the systemic response to, and the effect of, common breast cancer therapy on NF-kappaB and antioxidative defence enzyme expression and activity under clinical conditions are scarce. We determined these parameters in whole blood cell lysate from 16 women with breast cancer before and after combined (cyclophosphamide, doxorubicin, 5-fluorouracil; CAF) therapy and compared the results with 16 healthy women. Significantly higher levels of NF-kappaB and Mn-SOD (both their protein level and their activity) were found in breast cancer patients before and after CAF therapy, in comparison with healthy women. In parallel measurements, no change in the level or activity of catalase (CAT) was detected. According to our findings, it appears that breast cancer creates conditions that increase the level of hydrogen peroxide in the circulating cells and that the applied CAF therapy fails to compensate, therefore creating systemic conditions that favour survival and invasion of breast cancer cells.  相似文献   
59.
The report presents two cases of neurofibromatosis type 1 one previously known and one detected during pregnancy. It describes how the disease was detected and diagnosed, and what was the outcome of pregnancies. This is the first case of prenatal neurofibromatosis type 1 diagnosed in our clinic.  相似文献   
60.
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