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91.
Hiroyuki Yamamoto Fumio Itoh Akinori Senota Yasushi Adachi Mitsuru Yoshimoto Takao Endoh Yuji Hinoda Akira Yachi Kohzoh Imai 《Journal of clinical laboratory analysis》1995,9(5):297-301
The matrix metalloproteinase matrilysin (MMP-7) is a member of the matrix metallo-proteinase gene family, which is believed to play an important role in tumor invasion and metastasis. We have previously found that matrilysin mRNA is specifically expressed in colorectal cancers and adenomas and that its message is localized in the tumor cells themselves. We examined the effects of activated Ki-ras oncogene on the expression of matrilysin in colon cancer cells. We showed that both mRNA and the enzymatic activity of matrilysin were induced by the introduction of activated Ki-ras into SW1417 colon cancer cells. To understand the mechanisms regulating this induction, we analyzed alterations of AP-1 activity induced by activated Ki-ras, using the chloramphenicol acetyltransferase assay. AP-1 activity in SW1417 cells expressing activated Ki-ras was higher than that in control cells. The gel-shift assay also showed higher levels of AP-1 binding protein in SW1417 cells expressing activated Ki-ras than those in control cells. Our results suggest that activated Ki-ras may play a role in inducing expression of matrilysin through an AP-1-dependent pathway in colon cancer cells. 相似文献
92.
Changes in the levels of urea cycle enzymes and polyamine metabolism in the liver of rats treated with alpha-naphthylisothiocyanate (ANIT), an inducer of experimental cholestasis, were studied. Activities of arginase increased approximately two-fold compared to the control values during the period of 24-72 hours after oral administration of ANIT (100 mg/kg), while activities of ornithine carbamyltransferase and ornithine aminotransferase decreased. The activity of ornithine decarboxylase was elevated by approximately 20- and 10-fold at 12 and 60 hours, respectively, after ANIT administration. Putrescine concentration doubled 24-48 hours after the ANIT administration, but spermidine level rose more slowly and reached the level of 1.5-fold of the control level in 36-72 hours. Spermine concentration decreased initially but increased in 96 hours. These results suggest that the increased activity of urea cycle accounts for the increase in the ornithine content and that the putrescine and spermidine acts as the initiator of recovery of the liver damaged by ANIT treatment. 相似文献
93.
Two-level posterior lumbar interbody fusion for degenerative disc disease: improved clinical outcome with restoration of lumbar lordosis 总被引:2,自引:0,他引:2
Akira Hioki MD Kei Miyamoto MD PhD Hirotaka Kodama MD PhD Hideo Hosoe MD PhD Hirofumi Nishimoto MD Hirofumi Sakaeda MD PhD Katsuji Shimizu MD DMSc 《The spine journal》2005,5(6):600-607
BACKGROUND CONTEXT: Although posterior lumbar interbody fusion (PLIF) for degenerative lumbar diseases is routine, there are few reports on double-level PLIF. PURPOSE: To evaluate the clinical outcomes of double-level PLIF. STUDY DESIGN/SETTING: A retrospective study of operated cases in Gifu, Japan. PATIENT SAMPLE: Nineteen patients (8 men and 11 women, 59.5+/-10.2 years) who underwent double-level PLIF between 1996 and 2001. OUTCOME MEASURES: Operation time, blood loss, complications, the Japanese Orthopaedic Association (JOA) score for back pain and lumbar sagittal alignment were evaluated. METHODS: Patients were examined retrospectively at follow-ups of 3.6+/-1.7 years. Primary diseases were spondylolisthesis, spinal canal stenosis, degenerative scoliosis and herniated intervertebral disc. Fusion areas were L3 to L5 in 15 cases and L4 to S1 in 4 cases. RESULTS: The mean JOA score increased from an initial score of 12.9+/-3.5 to 21.3+/-4.9 at the final follow-up. There was a positive correlation (R=0.718, p<.001) between the increase in lordotic angle and the increase in the JOA score. Several parameters suggested that the surgical invasiveness was not minimal. CONCLUSION: Double-level PLIF provided satisfactory results and preserved lumbar spine lordosis. 相似文献
94.
Kazumasa Miyake Atsushi Tatsuguchi Mikiko Tachibana Masanobu Kusunoki Yoko Shinji Kei Shinoki Tetsuro Hiratsuka Kazuhiro Nagata Hitoshi Nishigaki Seiji Futagami Ken Wada Taku Tsukui Toshiro Yoshiyuki Akira Tokunaga Takashi Tajiri Choitsu Sakamoto 《Digestive endoscopy》2004,16(2):172-175
A 52‐year‐old Japanese woman who presented with gastrointestinal (GI) bleeding underwent a proximal gastrectomy for a gastrointestinal stromal tumor (GIST) with a foveolar hyperplasia at the apex of the tumor, 4.5 cm in size, located in the upper body of the stomach. Although GIST are often asymptomatic and are found only incidentally, clinical symptoms such as bleeding, abdominal pain, or obstruction, occasionally lead to a premorbid diagnosis. When submucosal tumors present GI bleeding, the source of the bleeding usually is an ulceration of the mucosa over the tumor. However, in the present study, it was thought that the bleeding originated from the region of foveolar hyperplasia. 相似文献
95.
Tsuyoshi Shimizu Shigeki Ito Yujiro Kikuchi Masaharu Misaka Tetsuzo Hirayama Shin Ishimaru Akira Yamashina 《European journal of cardio-thoracic surgery》2004,25(4):578-584
OBJECTIVES: Graft failure has been reported when the arterial conduit, such as the internal thoracic artery (ITA) or the right gastroepiploic artery (GEA), is grafted to a lower grade coronary artery stenosis. The shear stress as a significant factor affecting graft patency was compared between the arterial conduit and the saphenous vein graft (SVG) after surgery. METHODS: In 101 patients, 40 ITAs, 27 GEAs and 34 SVGs were examined using a Doppler-tipped guide wire during postoperative angiography. The graft flow volume and shear stress were calculated from velocity and diameter data. The study grafts were classified according to the grade of native coronary artery stenosis: group L had more than 50 up to 75% stenosis, and group H had more than 75% stenosis. Group H consisted of 25 ITAs, 17 GEAs and 21 SVGs, while group L consisted of 15 ITAs, 10 GEAs and 13 SVGs. RESULTS: In group H, graft flow volume did not significantly differ among the ITA (34+/-11 ml/min), GEA (36+/-16 ml/min) and SVG (41+/-15 ml/min), and graft shear stress significantly (ITA vs. GEA P<0.0001; GEA vs. SVG P<0.01) differed among the ITA (16.0+/-4.8dyn/cm(2)), GEA (9.1+/-3.2dyn/cm(2)) and SVG (4.8+/-1.6dyn/cm(2)). In group L, flow volume was lower (P<0.001) in the ITA (18+/-6 ml/min) and GEA (13+/-8 ml/min) than in the SVG (35+/-16 ml/min), and shear stress was significantly (P<0.001) greater in the ITA (13.7+/-4.9dyn/cm(2)) than the GEA (5.6+/-2.0dyn/cm(2)) or SVG (4.6+/-2.0dyn/cm(2)). CONCLUSIONS: These data suggest that shear stress of the ITA is superior and maintained despite the flow volume being reduced by flow competition. Lower shear stress of the GEA for intermediate stenosis may be associated with the development of conduit failure. 相似文献
96.
97.
98.
Y Aso Y Ohtawara K Fukuta H Sudoko M Nakano T Ushiyama N Ohta K Suzuki A Tajima 《The Journal of urology》1987,137(4):629-632
We tested 2 prototypes of an operating fiberoptic nephroureteroscope, measuring 3.5 and 4.5 mm. in diameter, that have an adequate working channel for auxiliary instruments and irrigation. Difficulty in passing the fiberscope through the ureteral orifice was overcome by dilation with balloon and polytetrafluoroethylene (Teflon) dilators. Our initial trial for stone retrieval under fiberscopic control was performed on 21 patients with upper ureteral and renal calculi. A stone was removed successfully in 15 of the 21 patients (71 per cent). After electrohydraulic lithotripsy calculi were extracted successfully in 9 of 11 patients (82 per cent). Three patients suffered ureteral perforation. The fiberscope was especially helpful when an upper ureteral stone moved back to the kidney during stone manipulation. 相似文献
99.
J Kusakari K Hozawa T Hanazima S Suzuki T Takasaka N Sasano 《Archives of oto-rhino-laryngology》1987,244(4):246-248
We report a case of cylindrical cell papilloma of the paranasal sinuses. This tumor originated in the medial wall of the left maxillary sinus of a 69-year-old man and extended to the surrounding tissues. Pathological study of tissue sections from the tumor showed typical findings of cylindrical cell papilloma with no evidence of associated malignancy. Histochemical and electron microscopic examinations revealed a large number of mitochondria in the cytoplasm of the tumor cells. The tumor was removed through a Denker's approach. The patient did well following surgery and there has been no sign of recurrence in a 2-year follow-up study. 相似文献
100.
A considerably large number of ECGs of pediatric patients had small notches and slurs on QRS complexes. By sampling these ECGs at higher rates, namely 4 KHz, it was shown that the higher rate data accurately reconstructed the notches and slurs on the QRS complex which were occasionally missed or distorted when the sampling rate was 250 Hz. When using the sampling rate of 250 Hz, it was observed that the reduction of the peak-to-peak amplitude of a QRS complex exceeded 0.1 mV in nearly 30 percent of tested cases, even if the ECG did not contain unwanted noise signals. Moreover, if there is relatively more noise in children's ECGs, one should reduce noise in such data in order to prevent measurement errors in the succeeding steps of the computer program. In such circumstances, the higher sampling rate would be preferable since filtering techniques which are used to reduce noise may considerably affect the estimation of the onset, offset and amplitude of the intrinsic ECG signals if the sampling rate is low. The reduction of the price of computers and their peripheral devices may facilitate the adoption of the higher sampling rate. From these considerations it was concluded that the use of the higher sampling rate might be both practical and an effective measure to enhance the diagnostic performance of the computer ECG systems. 相似文献