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71.
Increased accumulation of iodine-123-IMP in the pulmonary inflammatory lesion surrounding a lung cancer 总被引:1,自引:0,他引:1
Masayuki Nakajo Noriaki Uchiyama Yoshiyuki Hiraki Yoshihiko Miyata Atsuhisa Iriki Yasunobu Hirotsu Joeji Wakimoto Yoshimasa Norimatsu 《Annals of nuclear medicine》1988,2(1):49-53
In a patient with primary lung cancer, increased accumulation of I-123-IMP was observed in a pulmonary inflammatory lesion surrounding a lung cancer which was delineated as a photon deficient area. Ga-67-citrate uptake was observed in both the inflammatory and cancerous areas. These findings suggest that I-123-IMP may have the potential to accumulate differently in a variety of pathological conditions of the lung and thus may be a clinically useful lung imaging agent. 相似文献
72.
73.
High Cell-Density Culture System of Hepatocytes Entrapped in a Three-Dimensional Hollow Fiber Module with Collagen Gel 总被引:2,自引:0,他引:2
Kazuyoshi Takeshita Haruaki Ishibashi Masayuki Suzuki Takumi Yamamoto Toshihiro Akaike Masashi Kodama 《Artificial organs》1995,19(2):191-193
Abstract: A compact three-dimensional (3D) module is needed for hepatocyte culture in order to develop an effective hybrid artificial liver system that can retain hepa-tocellular structure and differentiated functions. We treated the 3D module with collagen gel to entrap rat hepatocytes. This method yielded a high hepatocellular density (2 times 107 cells/ml) over a period of 14 days and maintained the secretion of albumin and ureogenesis at the same level as the control monolayer method. The ammonia removal remained at 43% of the Day 0 value over 8 days of perfusion. Our data show that this approach may be useful for liver support therapy in an ex-tracorporeal circuit. 相似文献
74.
Hiroshi Inada Hiroyuki Horio Kiyomu Ishikawa Hiromichi Yoshikawa Eishi Harasawa Hidehiro Hosaka 《Journal of medical systems》1993,17(3-4):257-266
A filing system for ocular fundscopic image data was developed by using a personal computer for the Twin AMHTS. The development of the system was tried as one of the data transfer system including image data between two similar AMHTSs named the Twin AMHTS through the information network system. The filing system is capable of storing 26782 data of ophthalmoscopic pictures with a data compression mode by using a magneto-optical disk (MOD) whose storage capacity of both sides is 616 MB. It takes no long time for retrieval and display of the image data in the filing system. Good quality of compression and decompression obtained and reproducibility of the ocular fundus picture is favorable regardless of normal or abnormal cases. As a result, it is suggested that the developed system has practical utility although it requires more improvement. 相似文献
75.
S Shinozaki Y Matsuzawa S Yoshikawa K Fujimoto S Yamaguchi K Harada K Kubo T Kobayashi M Sekiguchi 《Nihon Kyōbu Shikkan Gakkai zasshi》1991,29(8):954-962
The authors studied the effects of natural panting frequency (NF) and the cheek support on the plethysmographic measurement of thoracic gas volume (TGV) in 8 normal subjects (non-smokers) and 46 patients with chronic obstructive pulmonary disease (COPD). The patients were divided into 2 groups according to the degree of airway obstruction (group I; specific airway conductance (SGaw) greater than 0.1 (n = 18), group II; SGaw less than 0.1 (n = 28)). TGV was measured with a pressure-type body plethysmograph (BP). NF was 2.00 +/- 0.43 Hz (mean +/- SD) in control subjects, 1.92 +/- 0.78 Hz in group I, and 1.39 +/- 0.59 Hz in group II, respectively, indicating lower NF in the patients with severe airway obstruction. In control subjects and group I, the differences between TGV at NF and at 0.5-1.0 Hz (TGVNF-TGV1.0) were -0.01 +/- 0.07L, and -0.06 +/- 0.16L, respectively, and cheek support did not alter the difference. On the other hand, in group II, the difference was slightly larger than other groups in spite of the lower NF, and this overestimation was abolished by cheek support (0.13 +/- 0.25L-----0.06 +/- 0.27L, p less than 0.05). These results suggest that, in patients with severe airway obstruction, TGVNF may be overestimated even if NF is relatively low. This overestimation may be mainly due to the extrathoracic airway compliance including the cheek. 相似文献
76.
The integrity of the sensory nervous system in the anal canals of chronically constipated children was investigated using
evoked potential techniques examining cerebral and spinal evoked potentials from the lower extremities and anal canal. Stimulation
of the posterior tibial nerve produced no significant difference in the parameters of spinal and cerebral evoked potentials
between 18 controls and 12 chronically constipated chidren. However, stimulation of the anal canal resulted in evoked potentials
related to the age and/or consciousness level of the control children. Reproducible cerebral responses were obtained only
from nine of these control children, all aged over 4 years, who were examined while awake without sedatives. A typical response
was characterized by a polyphasic wave occurring with an onset latency of 79.4± 27.7ms (mean ±SD). In the 12 chronically constipated
children, the 5 sedated patients examined while asleep did not show any reproducible potential, as in the controls. However,
in the remaining 7 children examined while awake, the occurrence of the anal canal evoked potential was significantly reduced,
and only two exhibited a cerebral response. These findings suggest that rectal mucosal perception of the intraluminal stimuli
might be disturbed in some children with chronic constipation. 相似文献
77.
Tatsuya Nomura Tokihiro Yoshikawa Hideo Kato Keiya Nikkuni Koichi Sasaki Yoshio Shirai Katsuyoshi Hatakeyama 《Surgery today》1997,27(4):334-336
A case of early gastric cancer, limited to submucosal layer, which was manifested as cerebral metastasis is presented herein. A 47-year-old man was admitted to Nagaoka Chuo General Hospital with convulsions and a disturbance in consciousness, where a computed tomography (CT) scan revealed a cerebral tumor in the left temporal lobe. The resected tumor was identified as a metastatic adenocarcinoma. Further investigation revealed gastric cancer involving the posterior wall of the cardia. At laparotomy, multiple and small metastases of the liver and a jejunal metastasis were found, and a palliative total gastrectomy was performed. The surgical specimen revealed a protruding, poorly differentiated medullary adenocarcinoma, with invasion of the submucosal layer. The patient died 4 months after undergoing the laparotomy. This case report is presented to make clinicians aware of the possibility that early gastric cancers may present as brain metastasis. 相似文献
78.
Yasuna Kobayashi Ryoko Sakai Naomi Ohshiro Masayuki Ohbayashi Noriko Kohyama Toshinori Yamamoto 《Drug metabolism and disposition》2005,33(5):619-622
Organic anion transporter 2 (Oat2 [SLC22A7]) is a multispecific organic anion transporter. Although several substrates of human Oat2 (hOat2) have been elucidated, a possible involvement of hOat2 in drug interaction is less defined. The purpose of this study was to investigate the interaction of theophylline with erythromycin mediated by hOat2 using a Xenopus laevis oocyte expression system. When expressed in Xenopus oocytes, hOat2 mediated the transport of theophylline and erythromycin. The finding indicates that the two compounds are novel substrates for hOat2. The apparent K(m) values for the uptake of hOat2 that mediated the transport of theophylline and erythromycin were 12.6 muM and 18.5 muM, respectively. The hOat2-mediated uptake of [(14)C]theophylline and [(14)C]erythromycin was cis-inhibited by adding erythromycin and theophylline, respectively. Our present findings suggest that hOat2 may, at least in part, be involved in the theophylline-erythromycin interaction in the human liver. 相似文献
79.
Dendritic Cells Coinjected with Tumor Cells Treated with an Anticancer Drug to Induce Tumor Rejection 总被引:1,自引:0,他引:1
Naoya Inoue Seiji Yamasaki Kan Kondo Takatsugu Kan Katsuyoshi Furumoto Masayuki Imamura 《Surgery today》2003,33(4):269-276
Purpose: We examined whether bone marrow-derived dendritic cells (DCs) could induce antitumor immunity when a chemotherapeutic drug
was added.
Methods: CT26 (a murine colon cancer cell line syngeneic with BALB/c) and CT26-bearing mice were treated with mitomycin C (MMC) intraperitoneally
(i.p.). Next, mice immunized with a coinjection of DCs and MMC-treated CT26 (i.p.) were given an intradermal inoculation of
CT26. Finally, CT26-bearing mice were treated with MMC (i.p.) with or without DCs, given peritumorally.
Results: Although the inoculated tumor was not rejected in the control mice, CT26 was rejected in 50% of the mice injected with MMC
alone. Apoptosis was observed in the MMC-treated CT26 cells in vitro and in vivo. Immunization with DCs and apoptotic CT26
cells, but not with apoptotic CT26 alone, gave protection against tumor challenge in 7 of 13 mice. A significantly higher
level of cytotoxic T-cell activity and interferon-γ production was seen in the protected mice. When MMC (i.p.) treatment was
followed by peritumoral DC injection in the CT26-bearing mice, remarkable therapeutic effects were observed.
Conclusion: DCs can collaborate with chemotherapy-induced apoptotic tumor cells and elicit improved antitumor immunity, probably through
the acquisition of tumor-associated antigens from apoptotic tumor cells.
Received: January 7, 2002 / Accepted: September 3, 2002
Acknowledgments. We thank Dr. Kazuo Kinoshita for his useful advice on using flow cytometry. This research was partly supported by the Ministry
of Education, Culture, Sports, Science and Technology (No. 11671160).
Reprint requests to: S. Yamasaki 相似文献
80.
Songji Zhao Yuji Kuge Takafumi Mochizuki Toshiyuki Takahashi Kunihiro Nakada Masayuki Sato Toshiki Takei Nagara Tamaki 《Journal of nuclear medicine》2005,46(4):675-682
The biologic mechanisms involved in the intratumoral heterogeneous distribution of 18F-FDG have not been fully investigated. To clarify factors inducing heterogeneous 18F-FDG distribution, we determined the intratumoral distribution of 18F-FDG by autoradiography (ARG) and compared it with the regional expression levels of glucose transporters Glut-1 and Glut-3 and hexokinase-II (HK-II) in a rat model of malignant tumor. METHODS: Rats were inoculated with allogenic hepatoma cells (KDH-8) into the left calf muscle (n = 7). Tumor tissues were excised 1 h after the intravenous injection of 18F-FDG and sectioned to obtain 2 adjacent slices for ARG and histochemical studies. The regions of interest (ROIs) were placed on ARG images to cover mainly the central (CT) and peripheral (PT) regions of viable tumor tissues and necrotic/apoptotic (NA) regions. The radioactivity in each ROI was analyzed quantitatively using a computerized imaging analysis system. The expression levels of Glut-1, Glut-3, and HK-II were determined by immunostaining and semiquantitative evaluation. The hypoxia-inducible factor 1 (HIF-1) was also immunostained. RESULTS: ARG images showed that intratumoral 18F-FDG distribution was heterogeneous. The accumulation of 18F-FDG in the CT region was the highest, which was 1.6 and 2.3 times higher than those in the PT and NA regions, respectively (P < 0.001). The expression levels of Glut-1, Glut-3, and HK-II were markedly higher in the CT region (P < 0.001) compared with those in the PT region. The intratumoral distribution of 18F-FDG significantly correlated with the expression levels of Glut-1, Glut-3, and HK-II (r = 0.923, P < 0.001 for Glut-1; r = 0.829, P < 0.001 for Glut-3; and r = 0.764, P < 0.01 for HK-II). The positive staining of HIF-1 was observed in the CT region. CONCLUSION: These results demonstrate that intratumoral 18F-FDG distribution corresponds well to the expression levels of Glut-1, Glut-3, and HK-II. The elevated expression levels of Glut-1, Glut-3, and HK-II, induced by hypoxia (HIF-1), may be contributing factors to the higher 18F-FDG accumulation in the CT region. 相似文献