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81.
Increased expression of mRNAs for microtubule disassembly molecules during nerve regeneration 总被引:2,自引:0,他引:2
Iwata T Namikawa K Honma M Mori N Yachiku S Kiyama H 《Brain research. Molecular brain research》2002,102(1-2):105-109
The mRNA expression of the microtubule disassembly molecules (SCG10, stathmin, SCLIP and RB3) in response to nerve injury was examined using a rat hypoglossal nerve injury model. After nerve injury prominent increase in mRNA expression of SCG10, stathmin and RB3 was observed, while only slight increase in SCLIP mRNA was observed in injured motor neurons. The increase in SCG10 and RB3 mRNA expression was quicker than that of stathmin and SCLIP. All the elevated signals decreased gradually to control levels by 4 weeks after nerve injury. 相似文献
82.
Hara R Itami J Aruga T Kozuka T Yamashita H Abe Y Fuse M Kondo T Shinohara D Nagaoka T Kobiki T 《Nihon Igaku Hōshasen Gakkai zasshi. Nippon acta radiologica》2002,62(4):156-160
Stereotactic radiosurgery for body tumors is hampered by the difficulties in body fixation and respiratory motions of the tumor. We have developed a Microton-based system for the stereotactic irradiation of body tumors, which delivers radiation at a predetermined respiratory phase. The patients are fixed non-invasively in the custom-made bed, and CT images are obtained. The isocentor is calculated with reference to those images and is marked onto the patient's skin and the custom-made bed. The patient lying on the bed is transferred to the treatment couch of the Microtoron. After reproducing the isocenter, actual treatment is started. The treatment couch as well as the gantry move automatically around the isocenter according to the treatment planning. The circular collimator moves by computer control to reduce geometrical errors to less than 0.5 mm, which is evoked by gantry movement. Respiratory movement of the abdominal wall is measured by laser displacement monitor. The Microtron delivers X-rays at a predetermined respiratory phase with a lag time of 20 msec after the on-signal from the monitor. 相似文献
83.
Immediate early genes and p21 regulation in liver of rats with acute hepatic failure 总被引:10,自引:0,他引:10
Hui TT Mizuguchi T Sugiyama N Avital I Rozga J Demetriou AA 《American journal of surgery》2002,183(4):457-463
It has been observed that liver regeneration in acute hepatic failure (AHF) is suppressed [Eguchi et al. Hepatology 1996;24(6):1452-9]. The molecular mechanism regulating this inhibition is not known. We previously reported that in AHF rats, hepatocyte proliferation was significantly impaired with elevation in serum IL-6, TGF-beta1, and HGF [Kamohara et al. Biochem Biophys Res Commun 2000;273(1):129-35]. Following either 70% partial hepatectomy (PH) or liver injury, quiescent mature hepatocytes are "primed" to re-enter the cell cycle. The process of "priming" appears to be triggered by extracellular cytokines (IL-6 and TNF-alpha) and is characterized by expression of immediate early genes. Under the stimulation of growth factors such as HGF, "primed" hepatocytes exit the G1 phase of the cell cycle. G1-associated cyclins and their inhibitors play a pivotal role in G1/S cell cycle transition. Here, we demonstrate that immediate early gene (i.e. c-myc, c-fos) expression and AP-1 activity are preserved in AHF rat livers despite absence of hepatocyte proliferation. In contrast, p21 mRNA and protein are both over-expressed in AHF livers compared to livers from rats undergoing PH; this elevation leads to inhibition in Cdk2 activity, resulting in G1 cell cycle arrest and inhibition of regeneration. 相似文献
84.
Expressions of AMPA (GluR2, GluR3, and GluR4) and NMDA (NR1 and NR2) glutamate receptors in the spiral ganglion cells of the cochlea were analyzed both at protein and mRNA levels in control and deaf rats between week 0 (P14) and week 8 (P70) after deafness induced by a daily injection of kanamycin at P0-P14. In the deaf rats, significant up-regulations of GluR2, GluR3, and NR1 in the surviving spiral ganglion cells were observed, while expressions of GluR4 and NR2 were fairly constant. In contrast, in the control rats, the expressions of all these glutamate receptor subtypes were stable. These results suggest that drastic alterations in the diversity of GluR2/GluR3/NR1 receptor complexes in the surviving spiral ganglion cells, which result in alterations in Ca2+ permeability, may contribute to the deafness-related alterations in the structure and function of the cochlea. 相似文献
85.
Atsushi Horiuchi Yasuhito Abe Masazumi Miyake Katsuhiko Kimura Yasuo Hitsumoto Nozomu Takeuchi Shigeru Kimura 《Cancer science》1993,84(11):1165-1173
The expression of a membrane-associated lymphotoxin molecule (mLT) on lymphokine-activated killer (LAK) cells obtained from 18 patients with malignant tumors and its role in the tumor cell killing mechanisms were investigated. LAK cells from tumor-infiltrating lymphocytes (TIL-LAK cells) were mainly composed of CD3-positive cells, whereas LAK cells from peripheral blood lymphocytes (PBL-LAK cells) were mainly composed of CD16- and CD56-positive cells. However, mLT was found to be expressed on TIL-LAK cells as well as PBL-LAK cells. The degree of mLT expression correlated with the killing activity of LAK cells towards L929 cells (r=0.806, P <0.01, n = 15), but not with that towards Daudi or K562 cells. Although the degree of mLT expression correlated with the amount of secreted lymphotoxin (LT) in the supernatant of LAK cell culture, the secreted LT itself could not account for the tumor cell killing activity of LAK cells. Polyclonal rabbit anti-LT antibody partially inhibited the killing activities of LAK cells towards L929 cells and this inhibition was found in the combination of autologous tumor cells and PBL-LAK cells. These findings suggest the possibility that the mLT-related cytotoxicity is involved in the tumor cell killing mechanisms of TIL-LAK cells as well as PBL-LAK cells. 相似文献
86.
Evaluation of seminal vesicle characteristics by ultrasonography before and after ejaculation. 总被引:1,自引:0,他引:1
Twenty males underwent transrectal ultrasonography before and after ejaculation to examine possible alterations that could influence interpretation of seminal vesicle ultrasonography. The preejaculation length of 35 mm was significantly (p < 0.05) decreased to 30 mm after ejaculation. The mean width of the seminal vesicles was 13 mm before and 11 mm after ejaculation. The seminal vesicle volume was significantly diminished after ejaculation (p < 0.05). It therefore seems important to maintain a period of abstinence when evaluating the seminal vesicles by ultrasonography. 相似文献
87.
Treatment of hemospermia caused by dilated seminal vesicles by direct drug injection guided by ultrasonography 总被引:8,自引:0,他引:8
Bilateral seminal vesicle puncture and injection of drugs with ultrasound guidance were performed in patients with hemospermia resistant to conservative therapy and with dilated seminal vesicles. Of 7 patients 6 had resolution of hemospermia for 2 to 3 months and then relapse. No side effect was noted. 相似文献
88.
Y Fuse Y Tsuchihashi M Takamasu K Kawamoto T Kodama S Fujita K Kashima 《Gastroenterologia Japonica》1989,24(5):512-518
The thickness of Brunner's glands was measured using an ocular micrometer in 297 cases of surgically resected peptic ulcer and in 120 autopsy cases (control group). The mean maximum thickness of Brunner's glands in the control group was 1.55 +/- 0.37mm (mean +/- SD) and no difference in thickness was noted for each decade of age. The mean maximum thickness of Brunner's glands in patients with gastric ulcer, duodenal ulcer and gastroduodenal ulcer was 2.34 +/- 1.06, 3.18 +/- 1.07 and 3.24 +/- 1.05mm, respectively. When an ulcer is within the duodenum, Brunner's glands near the ulcer were thicker than those contralateral to it. In patients with gastric ulcer, Brunner's glands were the thickest in the pyloric ulcer group and negative correlation was noted between the thickness of Brunner's glands and the distance to the ulcer from the pyloric ring. Since gastric acidity is supposed to be lower when an ulcer is located more proximally, these results suggest that Brunner's glands become hyperplastic not only with the presence of an ulcer in the duodenum but also by acid hypersecretion of the stomach. 相似文献
89.
90.