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251.
Specialists of the Research Institute of Urology have practiced combination of transurethral resection (TUR) with electrovaporization in endoscopic treatment of bladder cancer (BC) since 1995. A total of 46 patients with transient cell BC (29 males and 17 females aged 49-87) stage Ta-T1 (32 patients) and T2-T3b (14 patients) underwent TUR or electrovaporization (if morphologically verified) of the exophytic part of the tumor. In addition, electrovaporization of the base of the tumor was made. Main indications for such treatment were standard indications for TUR in contraindications for more radical treatment. 6-24-month follow-up was possible in 23(71.9%) patients with superficial BC (group 1) and in 9(64.2%) patients with invasive BC (group 2). Endoscopically, the recurrence was detected in 3(13%) and 5(55.5%) patients of group 1 and 2, respectively. They were reoperated on with electrovaporization. It is inferred that TUR-vaporization of the bladder is an effective endoscopic treatment of superficial BC. Electrovaporization is a good palliative treatment in patients with invasive BC when radical surgery is impossible. It inhibits the progression of the disease, prevents hemorrhages due to the tumor destruction, reduces intraoperative blood loss, improves endoscopic visualization. It may also increase the operation ablasticity.  相似文献   
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We report on a very compact desk‐top transmission extreme ultraviolet (EUV) microscope based on a laser‐plasma source with a double stream gas‐puff target, capable of acquiring magnified images of objects with a spatial (half‐pitch) resolution of sub‐50 nm. A multilayer ellipsoidal condenser is used to focus and spectrally narrow the radiation from the plasma, producing a quasi‐monochromatic EUV radiation (λ = 13.8 nm) illuminating the object, whereas a Fresnel zone plate objective forms the image. Design details, development, characterization and optimization of the EUV source and the microscope are described and discussed. Test object and other samples were imaged to demonstrate superior resolution compared to visible light microscopy.  相似文献   
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Antitumour activity of cerebral cells at different stages of ontogenesis (embryonic, new-born, adult) has been studied. Researches have been carried out at killer-activity patterns in vitro with target-cells and tumour transplantation under mice kidney's capsule in vivo. It has been established that mice cerebral cells' suspension can decrease the tumour transplants' growth under kidney's capsule. Antiproliferative activity of embryonic and new-born mice cerebral cells was much higher than adult one. The kidney and liver new-born mice cells had no antiproliferative activity at all.  相似文献   
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Ukrain was found to be relatively resistant in vitro to mean intensity radiation over the whole UV range. Of the seven peaks in the absorption spectrum of Ukraine those at 210 and 230 nm are conspicuous in the spectrum of the plasma of colorectal patients injected the previous day with this drug.  相似文献   
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As a step towards elucidating the mechanisms of mutagenesis induced by irradiation and oxidation, we study the incorporation of 8-oxoguanine (OG) into duplex DNA. Molecular modelling is used to reveal changes in DNA conformational parameters due to mispairs within the sequences d(A5XA5).d(T5YT5) and d(G5XG5).d(C5YC5) where one of the bases of the bases of the central X:Y pair is OG and the other A,T,G or C. The G:C to OG:C replacements in DNA duplexes produce only minor conformational changes, similar to normal base sequence effects. The calculations suggest that both OG(syn):G and OG(syn):A mispairs can also be introduced without drastic distortion of sugar-phosphate backbone. The distortions produced by OG-containing mispairs are also found to be sequence dependent. Overall these calculations suggest that the G-->OG conversion could be an important factor in the irradiative or oxidative damage of DNA.  相似文献   
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