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11.
Kazushi Tsuda Keizo Kimura Hiroki Shima Ichiro Nishio Yoshiaki Masuyama 《Clinical and experimental pharmacology & physiology》1992,19(7):531-535
The present study was designed to investigate the presynaptic alpha 2-adrenoceptor function to inhibit norepinephrine (NE) release in blood vessels of reduced renal mass salt hypertensive rats (Na-loaded HT). Isolated perfused mesenteric vasculatures were prepared from Na-loaded HT and normotensive control rats (NT-control), and the NE release and vascular responsiveness were examined. Periarterial nerve stimulation caused a significantly greater release of NE and pressor responses in Na-loaded HT than in NT-control. Yohimbine, a potent alpha 2-adrenoceptor antagonist, demonstrated the facilitatory effects on NE release during nerve stimulation. The effects were significantly attenuated in Na-loaded HT compared with NT-control. These results demonstrate that vascular sympathetic nervous activity might be enhanced in Na-loaded HT. Furthermore, the increased NE release from vascular adrenergic neurons in Na-loaded HT could partially depend on impaired presynaptic alpha 2-adrenoceptor-mediated modulation, which might contribute to the pathogenesis and maintenance of this form of salt-dependent hypertension. 相似文献
12.
Nobuaki Miyazono M.D. Hiroki Inoue Akira Hori Ichiroh Kanetsuki Jurio Shimada Masayuki Nakajo 《Cardiovascular and interventional radiology》1994,17(1):36-37
We present a 44-year-old woman in whom a bronchialto-coronary artery communication via the conus branch was discovered after distal bronchial artery embolization with gelatin sponge for hemoptysis. If this bronchial-to-coronary artery anastomosis, not visible prior to embolization, had been inadvertently embolized, the patient could have developed a myocardial infarction. To reduce the likelihood of a serious complication, the possibility of this anastomosis should be kept in mind and angiography should be repeated before attempting proximal bronchial artery embolization. 相似文献
13.
Tsuyoshi Satoh Tadashi Watanabe Masanori Tadokoro Junichi Sakamoto Hiroki Murayama Katsuki Itoh Sadayuki Sakuma Hiroshi Takagi 《Cancer science》1992,83(4):379-386
Anti-carcinoembryonic antigen monoclonal antibody (MAb) CEA102 was produced by immunization with purified CEA and the specific accumulation of radiolabeled CEA102 in colorectal cancers was investigated by autoradiography of surgical specimens using Fuji Computed Radiography (FCR). Five patients with colorectal cancer were injected intravenously with 131 I-labeled intact CEA102 or its F(ab')2 . Primary tumor and liver metastases were successfully detected by external scanning with a gamma camera in 4 cases. Autoradiographic study of the surgical specimens using FCR showed predominant localization of 131 I-labeled CEA102 in primary tumors and liver metastases in all cases. Even a small liver metastasis (0.5 cm) was clearly visualized in the autoradiogram by FCR. The pixel distribution curves of the density of the respective tissues in the autoradiograms by FCR showed the heterogeneity of the distribution of administered radiolabeled MAb in individual tumors, but the density of the tumors was higher than that of the normal tissues. In the quantitative distribution analysis of CEA102, the uptake of the primary tumor (mean 1.10%ID/kg) was ten-fold greater than that of the normal colon mucosa (mean G.10%ID/kg). These results revealed that the application of MAb has great potential in radioimmunodetection as well as in antibody-directed therapy. 相似文献
14.
The ascidian tadpole larva represents the basic body plan of all chordates in a relatively small number of cells and tissue types. Although it had been considered that ascidians develop largely in a determinative way, whereas vertebrates develop in an inductive way, recent studies at the molecular and cellular levels have uncovered several similarities in the way developmental fates are specified. In this review, we describe ascidian embryogenesis and its cell lineages, introduce several characteristics of ascidian embryos, describe recent advances in understanding of the mechanisms of cell fate specification, and discuss them in the context of what is known in vertebrates and other organisms. Developmental Dynamics 236:1748–1757, 2007. © 2007 Wiley‐Liss, Inc. 相似文献
15.
T Isomura T Hisatomi R Satou S Matsuzoe A Hirano K Kosuga K Ohishi 《Kyobu geka. The Japanese journal of thoracic surgery》1992,45(3):208-211
Between January in 1988 and September in 1990, 65 patients underwent reoperation for acquired heart disease. Previous operations were closed mitral commissurotomy in 19, open mitral commissurotomy in 19, mitral valve replacement in 22, aortic valve replacement in one, and mitral repair in 4. After median sternotomy performed by hand-operated chisel and hammer, minimized dissection of the adhesive lesion was achieved. During the sternotomy, two patients required additional right thoracotomy because of marked median sternal adhesion and major cardiovascular injury occurred in three patients. Cardioplegic solution was introduced in normograde fashion except in two patients. In two patients with previous MVR by porcine prosthesis severe calcification was found in the left atrial wall and the prosthesis was not removed in one. Postoperative complications were low cardiac output syndrome requiring intra-aortic balloon pumping in two, re-thoracotomy due to hemorrhage in one, and mild air embolism without neurological damage in two. There was one early death (1.5%) but no late death. Although perioperative complication seemed to increase in reoperation, post-reoperative results was as good as those in the primary cardiac operation and reoperation on cardiac surgery should be performed before losing the indication for operation. 相似文献
16.
Hiroki Sakamoto Masayuki Kitano Takeshi Nishio Yoshifumi Takeyama Chikao Yasuda Masatoshi Kudo 《Digestive endoscopy》2006,18(3):206-211
Endosonography‐guided celiac plexus neurolysis (EUS‐CPN) safely and effectively relieves pain associated with intra‐abdominal malignancies when the neurolytic is accurately injected. We applied contrast medium to evaluate the ethanol injection sites in patients who received EUS‐CPN due to abdominal pain caused by malignancies. We injected, under the guidance of endoscopic ultrasonography (EUS), ethanol containing 10% contrast medium into the celiac plexus of patients with intra‐abdominal pain due to malignancies. Immediately after the endoscopic therapy, patients underwent computed tomography (CT) to confirm the injection site. Images of distribution of injected solutions were classified into three groups. Injected solution dispersed in unilateral and bilateral anterocrural space was defined as ‘unilateral injection’ or ‘bilateral injection’, respectively. Injected solution located out of the anterocrural space was defined as ‘inappropriate injection’. Pre‐ and postprocedure pain was assessed using a standard analog scale. Before and 2, 4, 8, 12, and 16 weeks after the procedure, pain scores were evaluated. From April 2003 to May 2005, 13 patients were enrolled in this study. Improvement of pain score in the ‘bilateral injection’ and ‘unilateral injection’ groups was significantly superior to the change in the ‘inappropriate injection’ group. Although EUS‐CPN was effective in eight of 13 patients (61.5%), additional EUS‐CPN to the ‘inappropriate injection group’ increased the response rate to 84.6%. Injection of ethanol to the anterocrural space by EUS‐CPN produced adequate pain relief. Immediate examination by CT for confirmation of injection sites after EUS‐CPN would increase the likelihood of induction of pain relief. 相似文献
17.
Hiroshi Terasawa M.D. Kazuhisa Uchiyama M.D. Masaji Tani M.D. Manabu Kawai M.D. Takeshi Tsuji M.D. Katsuyoshi Tabuse M.D. Yasuhito Kobayashi M.D. Katsutoshi Taniguchi M.D. Hiroki Yamaue M.D. 《Journal of gastrointestinal surgery》2006,10(6):823-828
To determine the prognostic factors for patients with pathological T1 (pT1) carcinoma of the ampulla of Vater, 36 consecutive
patients with carcinoma of the ampulla of Vater who underwent surgery were retrospectively analyzed in terms of clinicopathological
features. The overall 5-year Kaplan-Meier survival in all patients was 50.2%, and the median survival of all patients was
64.0 months. Factors favorably influencing a long-term outcome were the absence of lymph node metastasis (P<0.0001), the absence of ulcer formation of the tumor (P=0.0062), and the absence of tumor invasion into the duodenum (P = 0.0025) and the pancreas (P=0.0098). In a multivariate analysis, lymph node metastasis was the only predictor of survival (P=0.0023). In the pT1 stage patients, 20% of the patients had lymph node metastasis, and their survival was statistically poor
compared to the pT1 patients without lymph node metastasis (P=0.017). As for survival after the operation, there was no significant difference between pancreatoduodenectomy and pylorus-preserving
pancreatoduodenectomy. 相似文献
18.
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
19.
Toshikazu Saito M.D. Hideaki Ishizawa M.D. Fumiaki Tsuchiya M.D. Hiroki Ozawa M.D. Naohiko Takahata M.D. 《Psychiatry and clinical neurosciences》1986,40(2):189-194
Abstract: Monoamine and their acid metabolites were determined in the CSF of 18 drug-treated chronic schizophrenic patients with the symptoms of tardive dyskinesia and neuroleptic-induced Parkinsonism (Parkinsonism). Six healthy volunteers were used as the control group.
The norepinephrine (NE) levels were found to be significantly higher in the patients with tardive dyskinesia than in the controls. Furthermore, elevated CSF NE levels were also observed in the patients with Parkinsonism. Epinephrine (E) and Dopamine (DA) were not present in the CSF of the control group, whereas measurable levels of DA could be detected in 4 out of 9 and E was found in 8 out of 9 patients with tardive dyskinesia. The mean concentration of HVA was slightly but not significantly elevated in the patients with tardive dyskinesia and Parkinsonism. The mean values of CSF 5-HIAA were all within the normal range in both patient groups. From the above results, it was suggested that abnormal adrenergic activity rather than abnormal dopaminergic activity may play an important role as a mechanism in the etiopathogenesis of extrapyramidal disorders. Furthermore, in the patients with Parkinsonism, CSF neurochemical observations were similar to those of the patients with tardive dyskinesia in this study. It may help to explain the clinical coexistence of tardive dyskinesia and neuroleptic-induced Parkinsonism. 相似文献
The norepinephrine (NE) levels were found to be significantly higher in the patients with tardive dyskinesia than in the controls. Furthermore, elevated CSF NE levels were also observed in the patients with Parkinsonism. Epinephrine (E) and Dopamine (DA) were not present in the CSF of the control group, whereas measurable levels of DA could be detected in 4 out of 9 and E was found in 8 out of 9 patients with tardive dyskinesia. The mean concentration of HVA was slightly but not significantly elevated in the patients with tardive dyskinesia and Parkinsonism. The mean values of CSF 5-HIAA were all within the normal range in both patient groups. From the above results, it was suggested that abnormal adrenergic activity rather than abnormal dopaminergic activity may play an important role as a mechanism in the etiopathogenesis of extrapyramidal disorders. Furthermore, in the patients with Parkinsonism, CSF neurochemical observations were similar to those of the patients with tardive dyskinesia in this study. It may help to explain the clinical coexistence of tardive dyskinesia and neuroleptic-induced Parkinsonism. 相似文献
20.
Histogenesis of the duodenum, especially changes in the epithelium in relation to temporal occlusion and re-canalization of
the lumen, was investigated by light microscopy together with morphometric analysis, as well as by scanning and transmission
electron microscopy of 133 externally normal human embryos ranging from Carnegie stage 12 to 23. A series of morphogenetic
events passed the duodenum in a cranio-caudal (proximo-distal) wave like fashion during the period examined. They included:
(1) a decrease in the caliber and area of the lumen, (2) ’occlusion’ of the lumen, (3) vacuole formation, (4) ’re-canalization’
and villi formation. The only exemption to this rule was that, in the upper part of the duodenum, the lumen was not obliterated
in the embryos examined. Morphometric analyses revealed that both the area of the epithelium and the number of epithelial
cells decreased during the ’occlusion’ phase. This result suggests that, unlike the classical view, epithelial cell proliferation
does not play an important role in occluding the lumen, but the predominant morphogenetic event during this phase is convergence
of the epithelial cells to elongate the duodenum. Apoptosis, contrary to some classical views, decreased during the ’re-canalization’
phase, and it appeared to be involved in the formation of the small lumens in the epithelial ’plug’ and in villi formation,
but not in enlarging the secondary lumens. The secondary small lumens in the occluded lumen were frequently formed near the
border between the central ’plug’ and peripheral basal cells on the basement membrane. This and other findings of concentric
differentiation in both the epithelial and mesenchymal layers suggested a possible control mechanism by the epithelium-mesenchymal
interaction on human duodenal morphogenesis and histogenesis. The present electron microscopic observations also provided
details on the mechanisms involved in the enlargement of the secondary lumen and differentiation of villi. The implications
of these findings to duodenal anomalies are also discussed.
Accepted: 12 November 2001 相似文献