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41.
Sugie Shigeyuki; Yoshimi Naoki; Tanaka Takuji; Mori Hideki; Williams Gary M. 《Carcinogenesis》1994,15(1):95-98
The nuclear pore density and area were measured on freeze-fracturednuclei of ACI/N rat liver altered foci, adenomas and carcinomasinduced by 2-acetylaminofluorene, and compared with those ofnormal hepatocytes. The pore density of nuclei from these preneoplasticand neoplastic lesions was significantly higher than that ofhepatocytes, but there was no difference between lesions. Thearea of nuclear pores of the focus cells did not differ fromnormal hepatocytes, whereas the areas of pores of adenoma andcarcinoma cells were increased. Moreover, the nuclear pore areaof carcinomas was significantly greater than that of adenomas.These results suggest that some changes may occur in nuclearpores in the progress of tumorigenesis. 相似文献
42.
To improve the rectal delivery of ethyl 4-biphenylylacetate (EBA), a prodrug of the anti-inflammatory drug 4-biphenylylacetic acid (BPAA), the use of highly water-soluble 2-hydroxypropyl-beta-cyclodextrin (HP-beta-CyD) and heptakis(2,6-di-O-methyl)-beta-cyclodextrin (DM-beta-CyD) was investigated and compared with the use of the parent beta-cyclodextrin (beta-CyD). Among the three beta-CyDs, HP-beta-CyD was best at improving the rectal bioavailability of EBA in rats after single and multiple administrations of oleaginous suppositories (Witepsol H-5) containing the complexes. To gain insight into the enhancing effect of beta-CyDs, the absorption behaviors of EBA (observed by monitoring BPAA as an active metabolite of EBA) and beta-CyDs themselves were examined in vitro, in situ, and in vivo. The in situ recirculation study revealed that the complexed form of EBA was less absorbable from the rectal lumen in the solution state, but this disadvantageous effect of beta-CyDs was compensated in part by the inhibition of the bioconversion of EBA to BPAA. When beta-CyDs were coadministered with EBA in vivo, however, rather high amounts of HP-beta-CyD (approximately 26% of dose) and DM-beta-CyD (approximately 21% of dose), compared with beta-CyD (approximately 5% of dose), were absorbed from the rat rectum. Thus, the enhancement of rectal absorption of EBA in vivo can be explained by the facts that the hydrophilic beta-CyDs increased the release rate of EBA from the vehicle and stabilized EBA in the rectal lumen and that the drug was partly absorbed in the form of the complex.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
43.
Shun'Ichi Abe Hiroshi Yoshimura Hideki Tabara Mitsuo Tachibana Naomi Monden Teruhisa Nakamura Saburou Nagaoka 《Journal of surgical oncology》1995,59(4):226-229
Patients with stage T3N0~2M0 gastric carcinoma (n = 108) were studied for relevant prognostic factors. Peritoneal lavage cytology (PLC) was performed in all. In univariate analysis, 5-year survival rates were better with smaller serosal invasion (diameter <3.0 cm vs. ≥3.0 cm, 61% vs. 37%, P < 0.05) and fewer metastatic nodes (≤5 vs. ≥6, 57% vs. 29%, P < 0.05). In multivariate analyses, only these two factors were significant. The predictive value of PLC was not shown in both univariate and multivariate analyses. Peritoneal recurrence occured in 14 (22%) of 77 patients with negative PLC, and in 3 (18%) of 17 with positive PLC, the difference being not significant. Our results indicate that PLC is insensitive in predicting the development of peritoneal recurrence. Its role in the estimation of survival is limited, as many will die of visceral or locoregional recurrence if not of peritoneal dissemination. 相似文献
44.
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46.
A Tsujimura K Nishimura K Matsumiya T Oka M Takaha R Arima A Kurata 《Hinyokika kiyo. Acta urologica Japonica》1992,38(9):1037-1040
A case of retroperitoneal venous aneurysm is reported. A 73-year-old woman was referred to us with the chief complaint of left abdominal mass. A giant abdominal mass was palpable and diagnostic imaging examination including ultrasound tomography, excretory pyelography, computed tomography, magnetic resonance imaging and angiography revealed a giant cystic mass encircled by calcification in the left retroperitoneal space. Operation for this cystic mass was performed under the preoperative diagnosis of a giant left renal cyst. During operation the mass was located between the left kidney and the left adrenal gland. Because it was difficult to separate the mass from the left kidney the mass was removed with the left kidney. The extirpated tumor measured 15.5 x 15.0 x 9.5 cm and contained old blood clots and red-yellow colored fluid. A histological examination revealed that the tumor wall was composed of smooth muscle and elastic fibers. Therefore, pathological diagnosis was retroperitoneal venous aneurysm. Retroperitoneal venous aneurysm is very rare. To our knowledge, this is the 8th case of retroperitoneal venous aneurysm reported in Japan. 相似文献
47.
3D kinematic analysis of the acromioclavicular joint during arm abduction using vertically open MRI.
Wataru Sahara Kazuomi Sugamoto Masakazu Murai Hiroyuki Tanaka Hideki Yoshikawa 《Journal of orthopaedic research》2006,24(9):1823-1831
Many researchers have evaluated the motions of the shoulder girdle, especially scapular and humeral motion. However, few reports exist that describe motions of the acromioclavicular joint. The purpose of the present study was to analyze the 3D kinematics of the acromioclavicular joint during arm abduction using 3D MR images obtained by a vertically open MRI. Fourteen shoulders of seven volunteers were examined in seven static positions from 0 degrees to the maximum abduction in a seated position. 3D surface models of the clavicle and scapula were created, and the movements of the acromioclavicular joint from 0 degrees to each position were calculated using the volume-based registration technique. From these calculations, the translations were evaluated and the rotational motions were analyzed using the concept of the screw axis. In the anteroposterior direction, the clavicle translated most posteriorly (-1.9 +/- 1.3 mm) at 90 degrees of abduction and most anteriorly (1.6 +/- 2.7 mm) at maximum abduction. In the superoinferior direction, the clavicle translated slightly superiorly (0.9 +/- 1.9 mm). When analyzing relative motion of the scapula with respect to the clavicle, the scapula generally rotated about a specific screw axis passing through the insertions of both the acromioclavicular and the coracoclavicular ligaments on the coracoid process. The average rotation was 34.9 +/- 8.4 degrees. 相似文献
48.
49.
Takashi Ohtsuka Hiroaki Nomori Tsuguo Naruke Hideki Orikasa Kazuto Yamazaki Keiichi Suemasu 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(3):154-156
A 58-year-old woman was admitted due to an abnormal shadow on chest X-ray, without any symptoms. Chest computed tomography
showed a round mass in the anterior segment of the right upper lobe. Segmentectomy was performed and histopathological examination
revealed a primary neurogenic tumor of Schwann cell origin. Immunohistochemical staining demonstrated the presence of S-100
protein in the tumor cells. We present a case of intrapulmonary schwannoma and review 62 cases of primary schwannoma of the
lung. 相似文献
50.
Ruri Aoki Tetsuya Arinobu Takeshi Kumazawa Hideki Hattori Hiroshi Noguchi 《Forensic Toxicology》2007,25(1):8-15
An automated on-line method for simultaneous analysis of five phenothiazine drugs by high-performance liquid chromatography
(HPLC)/sonic spray ionization mass spectrometry (SSI-MS) has been established, using backflush column switching. A 400-μl
portion of serum sample diluted 81-fold with distilled water was subjected to the on-line system. In the system, an Oasis
HLB cartridge was used as the precolumn for extraction; large molecules such as proteins in serum were discarded by use of
distilled water containing 0.1% formic acid as a mobile phase. After switching a valve, the analytes trapped in the precolumn
were eluted in the backflush mode and separated by a Chromolith Performance RP-18e column, which is composed of C18-bonded monolithic silica. The column effluents were then introduced into the SSI-MS. The present method provided successful
separation and determination of six phenothiazines including an internal standard. Satisfactory linearities, reproducibility,
and sensitivity were obtained at concentration levels that matched the toxic levels of phenothiazines. All drug peaks appeared
within 18 min, and the system could be reequilibrated in only about 8 min for the next run. Because of the simplicity and
rapidness of the method, it is likely to be useful in the fields of emergency medicine and forensic toxicology. 相似文献