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81.
Hideaki Ban Hiroyuki Kato Tsutomu Araki Hideaki Fujikura Yoshinari Hasegawa Kyuya Kogure 《Brain research》1994,646(2)
We investigated the effects of age and naftidrofuryl oxalate (Naftidrofuryl), a 5-HT2 antagonist, on neurotransmission and transduction systems in the gerbil hippocampus using quantitative autoradiography. [3H]Quinuclidinyl benzilate (QNB), [3H]cyclohexyl-adenosine (CHA), [3H]MK-801, and [3H]muscimol were used to label muscarinic acetylcholine, adenosine A1, N-methyl-d-aspartate (NMDA), and γ-aminobutyric acid-A (GABAA) receptors, respectively. [3H]PN200-110 labeled L-type Ca2+ channels. [3H]Forskolin, [3H]cyclic adenosine monophosphate (cAMP), [3H]phorbol 12,13-dibutyrate (PDBu), and [3H]inositol 1,4,5-triphosphate (IP3) were used to label adenylate cyclase, cAMP-dependent protein kinase, protein kinase C (PKC), and IP3 receptors, respectively. Approximately 20% reductions in [3H]QNB, [3H]forskolin, and [3H]PDBu binding were observed in the hippocampus of 9-month-old gerbils in comparison with 5-week-old gerbils. Treatment with Naftidrofuryl (10 mg/kg, i.p., once a day for 7 days) ameliorated these reductions. No changes were found in [3H]CHA, [3H]MK-801, [3H]muscimol, [3H]PN200-110, [3H]cAMP, and [3H]IP3 binding. The results suggest that Naftidrofuryl may have beneficial effects on the age-related alterations in signal transmission and transduction systems in the brain. Because the acetylcholine system, adenylate cyclase, and PKC are considered to be involved in learning and memory processes, the result may have clinical implications. 相似文献
82.
To clarify the mechanism of the origin of adenomyosis, we investigated the immunohistochemical distribution of collagen type III in the human endometrium and the adenomyosis throughout the menstrual cycle. 1) Collagen type III was localized in the stroma of normal endometrium and ectopic endometrium, and in the myometrium. No staining of collagen type III was observed in the endometrial gland. 2) The intensity of staining for collagen type III in the basal layer of normal endometrium was stronger than those in the functional layer. The staining in the proliferative phase was stronger than that in the secretory phase. 3) The intensity of staining of collagen type III in ectopic endometrium paralleled that in the basal layer of normal endometrium. 4) The intensity of staining of collagen type III in the myometrium did not change throughout the menstrual cycle. These results suggest that close similarities exist between stromal cells in normal endometrium and in ectopic endometrium from the viewpoint of the extracellular matrix. 相似文献
83.
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
84.
Shinichiro Kitada Kumiko Kato Alan J. Wein Robert M. Levin 《Neurourology and urodynamics》1989,8(3):255-262
We were able to produce two highly reproducible experimental models (in the rabbit) that demonstrated a high degree of reflex bladder contractile activity. In one model, a somatovesical reflex was induced by touching or pinching the perineal area. This reflex may be organized through a neurogenic reflex at the spinal level. In another model, rhythmic bladder contractions were produced by distal urethral constriction in the absence of bladder distension. These rhythmic contractions were thought to be due to a supraspinal reflex. In both types of contractile reflexes, intravenous administration of hexamethonium inhibited the reflex contractile activity virtually completely, intravenous atropine inhibited over 90% of the induced contractile activity, thus suggesting that these contractions were mediated reflexly through cholinergic stimulation. These two models of reflex bladder contractions should be useful for the study of hyperreflexic bladders. 相似文献
85.
A case-control study of breast cancer among Japanese women: with special reference to family history and reproductive and dietary factors 总被引:8,自引:0,他引:8
Dr. Ikuko Kato Dr. Shigeto Miura Fijio Kasumi Takuji Iwase Hideya Tashiro Yoshihiro Fujita Hiroki Koyama Tadashi Ikeda Kiyoshi Fujiwara Keiichi Saotome Kazuaki Asaishi Rikiya Abe Mitsuhiro Nihei Tsunehiro Ishida Takao Yokoe Hiroshi Yamamoto Motoi Murata 《Breast cancer research and treatment》1992,24(1):51-59
Summary To study the effects of family history and reproductive, anthropometric, and dietary factors on the risk of breast cancer among low risk populations, we conducted a hospital-based case-control study involving 908 patients with breast cancer and their matched controls, in Japan. A positive family history of breast cancer significantly increased the risk of breast cancer (odds ratio = 1.52, 95% confidence interval: 1.14–2.03). The risk further increased with increasing number of family members affected. Obesity, single marital status, fewer births, a late childbirth, and less consumption of green-yellow vegetables and dairy products were also associated with an increased risk of breast cancer. These associations were independent in multivariate analyses. There was no increase in risk associated with consumption of high fat foods. When analyzed by menopausal status, the association with family history of breast cancer, especially in the first degree of relatives, was more evident for premenopausal breast cancer. The associations with obesity and lower consumption of dairy products were more pronounced for postmenopausal breast cancer, while those with lower parity and single marital status were stronger for premenopausal breast cancer. 相似文献
86.
K Tozawa H Washida H Watanabe Y Noguchi M Kato Y Yamada 《Hinyokika kiyo. Acta urologica Japonica》1992,38(2):223-226
We report 3 cases of müllerian duct cyst. Percutaneous puncture, aspiration and instillation of a sclerosing agent under ultrasound guidance was performed in each case. Ultrasound is valuable in the diagnosis is of cysts in the region of the prostate and seminal vesicles. Aspiration under ultrasound guidance would also be of therapeutic value. 相似文献
87.
S Okabe K Takagi H Igata S Kato K Shimosako Y Yamaji M Seiki 《Japanese journal of pharmacology》1992,59(3):275-289
We examined the effects of a new compound, N-[3-[3-(piperidinomethyl)phenoxy]-propyl]-2-(2-hydroxyethyl-1- thio)acetamido.2-(4-hydroxy benzoyl)benzoate (Z-300), on the histamine H2-receptor, gastric secretion in rats and dogs, and acute gastro-duodenal lesions or chronic gastric ulcers in rats. Roxatidine acetate hydrochloride (roxatidine), a known histamine H2-receptor antagonist, was used as a reference compound. The pA2 values for Z-300 and roxatidine for the isolated guinea pig atrium were 6.8 and 7.0, respectively. These agents at less than 10(-5) M did not affect the contraction of guinea pig ileum in response to carbachol. Z-300, administered either orally or parenterally, significantly inhibited the basal and histamine-stimulated gastric acid secretion in rats. Gastric acid secretion stimulated by histamine, pentagastrin or carbachol in Heidenhain pouch dogs was also significantly inhibited by the compound. The effect persisted for greater than 7 hr in the case of histamine-stimulation. Oral Z-300 significantly protected the gastric mucosa from water-immersion stress-, indomethacin-, aspirin- and HCl.ethanol-induced lesions and protected the duodenal mucosa against mepirizole- and cysteamine-induced ulcers. These effects on gastric secretion and lesion formation were, as a whole, stronger than those observed with roxatidine. Z-300, but not roxatidine, significantly accelerated the spontaneous healing of acetic acid ulcers induced in rats and prevented the delay in ulcer healing caused by indomethacin. The mechanism of action of Z-300 on acute lesions and chronic ulcers appears to be mostly related to its potent antisecretory and mucosal-protective activities. 相似文献
88.
The local hyperthermochemotherapy for pleural carcinomatosis] 总被引:2,自引:0,他引:2
M Tsuboi K Nagai H Saitoh K Furukawa C Konaka H Kato K Kawana K Abe 《[Zasshi] [Journal]. Nihon Kyōbu Geka Gakkai》1992,40(8):1195-1202
Local hyperthermochemotherapy was performed in 17 cases to control malignant effusion and intrathoracic disseminated lesions. Of these 15 patients, 11 cases primary lung cancer, 4 cases metastatic lung cancer had pleural carcinomatosis and 2 cases were malignant diffuse mesotheliomas. The procedure was radiofrequency hyperthermia (13.56 MHz) maintaining the peripleural temperature at 42-43 degrees C for 45-60 minutes, combined simultaneously with the intrathoracic administration of cisplatin (1-2 mg/m2, bolus) through a thoracic double lumen trocar tube. The treatment was repeated from 2 to 4 times at 7-day intervals. In 14 cases (87.5%) complete or partial response according to the criteria of the Japan Lung Cancer Society were obtained. There were 2 cases of no change and one case that was impossible to evaluate. In one lung cancer case, the disappearance of pleural disseminated lesions was confirmed by flexible thoracoscopy after the procedure. In 12 cases, there were abdominal complaints due to side effects of the hyperthermochemotherapy, such as vomiting and nausea, but these symptoms were milder than those caused by intravenous injection of anti-cancer agents, for example cisplatin, in conventional chemotherapy treatment. The median survival time and 2 years survival of the patients with the present procedure were 15 months and 41.7% respectively. Although distant metastases appeared in most cases, none had local recurrence and particularly noteworthy pleural effusion was well controlled. The above experience suggested that the local hyperthermochemotherapy is useful to control pleural effusion and can improve the quality of life of patients with pleural carcinomatosis. 相似文献
89.
We recorded somatosensory evoked potentials (SEPs) from the skin surface and spinal evoked potentials (SpEP) from the posterior epidural space after median nerve stimulation in 11 patients with cervical syringomyelia. We compared SEPs with SpEP to assess the possible feasibility of using these techniques to localize the offending lesion. SEP abnormalities were present on one or both sides of 7 patients (9 of 22 upper limbs; 41%). The abnormal SEP pattern was the attenuation or loss of N13, which was of little value for delineating the lesion. In patients with abnormal SEPs, three types of abnormal SpEPs were noted. In the Type A abnormality (three limbs), potentials were attenuated in all cervical segments, suggesting that the syrinx itself had enlarged to involve the posterior column. In Type B (two limbs), there was reduced amplitude or absent upper cervical potentials, probably a result of the accompanying tonsilar herniation. Finally, the Type C (four limbs) abnormality was a mixture of Type A and B abnormalities in that the attenuated cervical potentials were again affected in the most upper cervical segment. We concluded that SpEP revealed various kinds of involvement of the dorsal column pathway in the syringomyelic patients, a finding not expressed with conventional SEPs. 相似文献
90.
An accurate and reproducible colorimetric assay was established to determine the concentration of basic fibroblast growth factor (bFGF) or bFGF-like activity in culture media and biological fluids. Fetal bovine heart endothelial cell line ATCC CRL 1395 was used as the bFGF-dependent cell line. The proliferation-stimulating activity of bFGF was determined by measuring the amount of formazan formed by the mitochondrial enzymes from a tetrazolium salt, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), instead of counting the viable cell numbers or measuring the incorporation of [3H]-thymidine. The addition of 250 ng/mL of heparin to the culture medium resulted in about a tenfold increase in the proliferation-stimulating activity of bFGF and allowed the detection of as low as 10 pg/mL of bFGF. Heparin also resulted in much smaller inter- and intraassay variations. The bFGF concentrations determined by this colorimetric assay correlated well with those determined by both the [3H]-thymidine incorporation assay using BALB/c 3T3 fibroblast cells (r = 0.998) and the cell number count assay (r = 0.996). This assay can be adapted to quantify bFGF or bFGF-like activity in tissue culture media and biological fluids such as plasma and organ extracts. 相似文献