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991.
The medical records of 133 patients with Stage I tongue cancer treated by definitive radiotherapy between 1966 and 2001 were reviewed. Overall survival rate (OS), progression free survival rate (PFS), and survival rate after recurrence were calculated according to the Kaplan-Meier method. We investigated prognostic factors for local control and risk factors of late neck LN metastasis. The 5-year OS was 81.8% and the 5-year PFS was 67.2%. The 5-year OS after local recurrence was 100% by salvage operation, and that after neck LN metastasis was 40.7% despite radical neck dissection. Tumor thickness over 5 mm and treatment without interstitial irradiation were prognostic factors for local control. Tumor diameter over 15 mm and tumor thickness over 5 mm were risk factors of late neck LN metastasis. We should consider prophylactic treatment for neck LN for high risk patients with Stage I tongue cancer in order to improve treatment results further.  相似文献   
992.
We examined whether sonoporation enhanced by a contrast agent (BR14) was effective in gene therapy for hepatocelluar carcinoma (HCC). Human hepatic cancer cells (SK-Hep1) and plasmid cDNAs expressing green fluorescent protein (GFP), interferonbeta (IFNbeta), and LacZ were used. In vitro, SK-Hep1 cell suspensions with DNA and BR14 were sonoporated. Expressions of every plasmid cDNA and the antitumor effect of IFNbeta were analyzed. In vivo, GFP and IFNbeta genes with BR14 were directly injected into subcutaneous tumors using SK-Hep1 in nude mice, and transcutaneous sonoporation of the tumors was performed. GFP gene transfections and tumor diameters after IFNbeta gene transfection were examined. In vitro, no SK-Hep1 cells were transfected without sonication, whereas transfections were successful after sonication with BR14. Antitumor effect of IFNbeta gene transfection by ultrasound (US) and with BR14 was revealed. In vivo, the SK-Hep1 cells expressed GFP, and the IFNbeta gene transfection by US with BR14 reduced tumor size significantly. In conclusion, gene therapy with sonoporation enhanced by a contrast agent may become a new treatment option for HCC.  相似文献   
993.
994.
With the new high-speed computed tomography (CT) devices, the longest scan time for a conventional scan is about 2 seconds. Therefore, the all-breathing-phase scan (slow scan) in the free-breathing state, which includes an entire breathing phase of three or four seconds in one imaging section, is impossible. We performed spiral scanning with a low-speed scanning pitch using multi detector-row CT (4MDCT) and examined a method of scanning that was similar to the slow scan method. As a result, with the scanning diagram, we demanded the image data time than a combination of scanning pitch and X-ray tube rotation time, image data time of 6.66 seconds longest in scanning slice thickness 1 mm x 4 detectors and reconstruction slice thickness 2 mm was possible, and the scanning that was similar to the slow scan method was possible. Furthermore, it was good in the image data time when we demanded it from scanning diagram and, as a result of confirmation of image data time by the equal speed turn phantom, agreed. In addition, there is not increase of a radiation exposure dose by this method, and this method is a useful method.  相似文献   
995.
Kazi JA  Liu EH  Lee TL  Tachibana S 《Neuroreport》2007,18(8):767-770
Nocistatin and nociceptin/orphanin FQ are two neuropeptides processed from the same precursor prepronociceptin. They have opposing roles in nociception and several other biological functions. Whereas the location and structure of the nociceptin/orphanin FQ receptors has been defined, the location of the nocistatin receptors remains unknown. In the course of this study, we synthesized a novel probe for histochemistry by linking biotin to the N terminus of nocistatin, and purified this with high-pressure liquid chromatography and confirmed the structure by mass spectrometer. Using this probe, we found nocistatin-binding sites in the cerebral cortex and the dorsal horn nucleus of the spinal cord. We also found that the nocistatin-binding sites were in the cell body, whereas the nociceptin/orphanin FQ binding sites were on the fibrous processes.  相似文献   
996.
997.
998.
NMDA受体抗体脑炎(NMDARE)具有特征性的神经和精神病学症状,NMDA受体抗体阳性,目前被认为是儿科最常见的自身免疫性脑炎之一.NMDARE的治疗策略,尤其是对于二线治疗的时机、长期免疫治疗方法等,仍具有较大的差异.来自北美、欧洲、亚洲等国家或地区的27位儿童神经科、风湿科等专业的专家代表,采用2-step De...  相似文献   
999.
In multicellular eukaryotes, geminin prevents overreplication of DNA in proliferating cells. Here, we show that genetic ablation of geminin in the mouse prevents formation of inner cell mass (ICM) and causes premature endoreduplication at eight cells, rather than 32 cells. All cells in geminin-deficient embryos commit to the trophoblast cell lineage and consist of trophoblast giant cells (TGCs) only. Geminin is also down-regulated in TGCs of wild-type blastocysts during S and gap-like phases by proteasome-mediated degradation, suggesting that loss of geminin is part of the mechanism regulating endoreduplication.  相似文献   
1000.
To gain insight into the mechanism of coordination of stepping in the fore and hind legs of quadrupeds, we examined the kinematics of leg movements and the motor patterns in fore and hind leg flexor muscles in decerebrate walking cats when the two pairs of legs stepped on separate treadmills running at different speeds. When the front treadmill was slowed progressively from 0.6 to 0.3 m/s with the rear treadmill running at 0.6 m/s, the rate of stepping in both the fore and hind legs decreased and a 1:1 stepping ratio was maintained. The decrease in the rate of stepping in the hind legs was due primarily to an increase in the duration of the swing phase. Slowing the speed of the rear treadmill while keeping the front treadmill speed at 0.6 m/s decreased the rate of stepping of the hind legs, but had relatively little influence on the average rate of stepping in the forelegs. In this situation stepping in the fore and hind legs was uncoupled and the time of stepping in one hind leg relative to the ipsilateral foreleg progressively shifted during a walking sequence. Analysis of the timing of electromyographic (EMG) recordings from flexor muscles of the hip and elbow joints yielded insight into the neuronal mechanisms underlying the asymmetry in slowing either the front or rear treadmill. We propose that ipsilateral pattern generating networks are asymmetrically coupled via descending inhibitory pathways and an ascending excitatory pathway. We discuss how the characteristics of these linkages are functionally appropriate for establishing the normal timing of stepping in the hind and forelegs during slow walking.  相似文献   
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