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Kazuhiko Yanai Tatsuo Ido Kiichi Ishiwata Jun Hatazawa Toshihiro Takahashi Ren Iwata Taiju Matsuzawa 《European journal of nuclear medicine and molecular imaging》1986,12(3):141-146
The endogenous hallucinogen, N,N-dimethyltryptamine (DMT), was labeled with carbon-11 and its regional distribution in rat brain studied. [11C]DMT showed higher accumulation in the cerebral cortex, caudate putamen, and amygdaloid nuclei. Studies of the subcellular distribution of [11C]DMT revealed the specific localization in the fractions enriched with serotonin receptors only when a very low dose was injected into rats. The proportions of the radioactivity in receptor-rich fractions were greatly enhanced by pretreatment with the monoamine oxidase inhibitor, pargyline. Specific binding of [11C]DMT to serotonin receptors in dog brain was demonstrated by a positron emission tomographic study in which 5-methoxy-N,N-dimethyltryptamine caused approximately 20% displacement of the radioligand from the receptors. 相似文献
3.
The role of several hippocampal innervations in the sensitivity to barbital-induced narcosis was studied in selected mice strains. The outbred and inbred mouse strains HS/Ibg, SABRA/HUC, C57BL, CBA/LAC, and BALB/c were tested for barbital-induced sleep (315 mg/kg). The relatively short sleeping HS/Ibg (HS) and the longest sleeping BALE/c (BALE) were chosen for further investigation. Cholinergic (ACh), serotonergic (5-HT), and noradrenergic (NE) innervations were studied in HS strain; whereas BALE, which possesses both an unusually high sensitivity to barbital and unique NE innervations in the cortex and hippocampus, was employed in a detailed study of the NE innervations. Transplantation of embryonic NE cells from the mouse embryo into the hippocampus of adult HS mice increased barbital narcosis by 65% (p < 0.05), whereas transplantation of 5-HT cells decreased barbital narcosis by 54% (p < 0.001). Transplantation of ACh cells had no significant effect on barbital-induced narcosis. BALB mice were subjected to NE cell transplantation into the hippocampus and cortex. Similarly to HS, BALB receiving NE transplants into their hippocampus slept 34% longer than control after barbital challenge (p < 0.025). Noradrenergic cell transplantation into frontal cortex had no effect on barbital sleep. The results suggest that (a) enhancement by neural grafting of the NE innervation to the hippocampus accentuates and enhancement of the 5-HT innervations attenuates the sensitivity to barbital narcosis, whereas ACh innervations have no effect on the sensitivity to barbital narcosis, and (b) the unusually high sensitivity of BALB mice to barbital may not be related to its unique NE innervations. 相似文献
4.
It is obvious that surgical resection is a superior therapy for gastric cancer. In this sense, endoscopic therapy could be regarded as an orphan in this field. However, in the combination of endoscopic therapy and ultrasonic endoscopy, endoscopic therapy for gastric cancer should be acknowledged to be equal to surgical therapy. We have treated early gastric cancer by means of endoscopical photocoagulation using a Nd-YAG laser, particularly in inoperable cases due to other complication or old age. Forty-seven lesions found in 41 patients have so far been photocoagulation and followed up. By this treatment, cancer cells disappeared in 42 out of 47 lesions, although 2 cases died of other diseases and recurrence was experienced in 3 cases. In addition to photocoagulation therapy using a laser, we have recently developed a large-biopsy technique called strip biopsy in order to get sufficient tissue for diagnosis in comparison with bite biopsy. By this method, we are able to resect the full thickness of the mucosa including the submucosal layer up to a size of about 4 cm, without any severe complication such as hemorrhage and perforation. We succeeded in resecting the early gastric cancer in 34 lesion in 31 patients. The combination therapy of endoscopical photocoagulation and strip biopsy seems to be reasonable for the therapy of early gastric cancer. 相似文献
5.
Ofer Gemer Benjamin Piura Shmuel Segal Ilana Yanai Inbar 《International journal of gynecological pathology》2003,22(4):398-400
Chondroid syringoma of the vulva is an extremely rare tumor. Of the previously reported cases, only one was clinically malignant. The authors describe a case of chondroid syringoma of the right labium majus from which arose a papillary adenocarcinoma. A right inguinal lymph node was replaced with metastatic adenocarcinoma. 相似文献
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The purpose of this study was to clarify the significance of immunohistological staining for PCNA/cyclin in human colorectal lesions. Our results: The PCNA-positive cells existed at the bottom of colonic tubuli in the normal and hyperplastic conditions. In the neoplastic lesions, however, the positive cells were existed at the relatively surface of the mucosa (chi 2: P less than 0.01) and distributed irregularly from the bottom to the top of carcinoma tissue. These results suggested that immunohistological staining for PCNA would specifically detect the cell proliferation and be beneficial for practical use and clinical application of the diagnosis of the colorectal lesions. 相似文献
8.
The relation of dietary factors to the risk of adenomas of the sigmoid colon was examined in men receiving a retirement health examination at the Self-Defense Forces Fukuoka Hospital between October 1986 and 1990. A total of 187 adenoma cases and 1557 controls with normal colonoscopy were identified in the series. Cases were further classified into small-adenoma (<5 mm, n=78) and large-adenoma (≥5 mm, n=67) groups. The consumptions of selected foods and beverages were ascertained before colonoscopy by means of a self-administered questionnaire. After adjustment for smoking, alcohol use, rank and body mass index, low rice consumption and high meat intake were independently associated with an increased risk of large adenomas. The risk of small adenomas was not related to either rice consumption or meat intake. Adjusted odds ratios of large adenomas for the low, intermediate and high consumption levels of rice were estimated to be 1.0 (referent), 0.83 and 0.43, respectively (trend P = 0.08), and the corresponding figures for meat consumption were 1.0 (referent), 1.58 and 2.38, respectively (trend P =0.02). The findings suggest that low rice consumption and high meat intake may promote the growth of colon adenomas, thereby increasing the risk of colon cancer. 相似文献
9.
Adenoid cystic carcinoma of the trachea and main-stem bronchus. A clinical, histopathologic, and immunohistochemical study 总被引:1,自引:0,他引:1
H Nomori S Kaseda K Kobayashi T Ishihara N Yanai C Torikata 《The Journal of thoracic and cardiovascular surgery》1988,96(2):271-277
Twelve cases of adenoid cystic carcinoma of the trachea and main-stem bronchus were histologically analyzed, and the results were examined with reference to the growth pattern of the tumor and the prognosis. The tumors were histologically classified into tubular, cribriform, and solid subtypes. Three histologic grades were established: grade I, tumors with tubular and cribriform subtypes but without solid subtype; grade II, tumors with tubular and cribriform subtypes in which the solid subtype comprised less than 20% of the area; grade III, tumors in which the solid subtype comprised more than 20% of the area. Three gross infiltrating types were established: type I, entirely intraluminal; type II, predominantly intraluminal; type III, predominantly extraluminal. In most cases histologic grade correlated with gross tumor type; that is, grades, I, II, and III were grossly types I, II, and III, respectively. The tumors infiltrating along the tracheobronchial wall were of the tubular or cribriform subtype, but not of the solid subtype. In two patients who died of distant metastasis, the histologic studies revealed the solid subtype. Immunohistochemical analysis demonstrated that the tubular subtype was the most differentiated form and the solid subtype, the most undifferentiated form. The histologic subtype of adenoid cystic carcinoma of the tracheobronchial tree was an important factor in the growth pattern of the tumor and the prognosis. 相似文献
10.
Summary Twenty-five shoulders were dissected in cadavers in order to observe the presence of the inferior transverse ligament, the spinoglenoid ligament, and its relationship to the spinoglenoid notch and the suprascapular nerve. The ligament was found to be absent in 50% of females and rudimentary in one female, but absent in only 13% of the male shoulders. The distance between the ligament and the bone, and from the ligament to the nerve was similar in males and females, but the variation was greater in males. These findings may explain the observation that distal suprascapular nerve entrapment occurs mostly in men.
Résumé Les auteurs ont disséqué vingt-cinq épaules de cadavres afin de vérifier la présence d'un ligament transversal inférieur, le ligament spinoglénoïdien, ainsi que ses rapports avec l'échancrure spino-glénoïdienne et le nerf sus-scapulaire. L'absence de ce ligament a été constatée chez 50% des sujets féminins et il était rudimentaire chez l'un d'entre eux. Chez les sujets masculins, il n'était absent que dans 13% des cas. La distance entre le ligament et l'os, et entre le ligament et le nerf était semblable chez les hommes et chez les femmes, mais les variations étaient plus importantes chez les hommes. Ces observations peuvent expliquer que la compression distale du nerf sus-scapulaire survienne plus fréquemment chez l'homme.相似文献