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11.
Effect of carbon dioxide and oxygen on endothelin production by cultured porcine cerebral endothelial cells 总被引:3,自引:0,他引:3
S Yoshimoto Y Ishizaki T Sasaki S Murota 《Stroke; a journal of cerebral circulation》1991,22(3):378-383
We have previously reported the production of endothelin, a potent vasoconstrictor peptide, by porcine cerebral microvessel endothelia and suggested its important role in the regulation of local blood flow within the brain. In our present study, radioimmunoassay with anti-porcine endothelin antiserum revealed that endothelin, produced by cerebral microvessel endothelia grown on a filter, is released mainly to the basement membrane side, not the vascular lumen side. This finding suggests that endothelin constricts arterioles locally where it is produced by endothelia. We also found that cerebral microvessel endothelia produce less endothelin under low oxygen pressure and more endothelin under low carbon dioxide pressure. Our results suggest that endothelin has a role in the regulation of cerebral blood flow in response to oxygen and carbon dioxide pressure. 相似文献
12.
To elucidate the molecular basis for endocrine tumorigenesis, p53 mutations in human endocrine tumors were analyzed by using polymerase chain reaction-single strand conformation polymorphism. Exons 5 through 10 of the p53 gene were studied in genomic DNAs from 134 primary endocrine tumors and 6 human endocrine cancer-derived cell lines. Mutations were detected and identified in 4 endocrine tumors, including one parathyroid adenoma and three thyroid carcinoma cell lines. The sites of these mutations were in exons 5 (codon 151 and 152) and 7 (codon 248 and 255). In all of three tumor cell lines, but not in a parathyroid adenoma, the normal allele encoding the p53 gene was lost. However, p53 mutations were not found in any other endocrine tumors or cell lines. Based upon these results, we concluded that the p53 gene may play a role in the tumorigenesis of a limited number of parathyroid adenoma and thyroid cancers, and that the p53 mutation with an allelic loss of the p53 gene is an important factor in malignant tumorigenesis of the thyroid gland. 相似文献
13.
Koichiroh Nandate Kenji Muranaka Koichi Shinohara Kazuyoshi Ishida Hiroko Ishida Katsuhiro Seo Hiroshi Takeshita 《Journal of anesthesia》1997,11(2):117-120
We retrospectively reviewed the records of 250 consecutive patients undergoing coronary artery bypass graft surgery (CABG)
from January 1994 through January 1996 to determine the incidence of persistent postoperative neurological dysfunction after
CABG and to compare normothermic and moderate hypothermic cardiopulmonary bypass (CPB). Normothermic CPB was used in 128 patients
(36°–37°C) and hypothermic CPB (27°–28°C) in 122 patients. Postoperative neurological dysfunction included focal motor deficits,
delayed recovery of consciousness (>24h) after surgery, and seizures within 1 week postoperatively. Persistent neurological
dysfunction was diagnosed if complete resolution had not occurred within 10 days of surgery. The incidence of persistent postoperative
neurological dysfunction was 4.1% in the hypothermic CPB group and 2.3% in the normothermic CPB group. There were no statistically
significant differences between the two groups (P=NS). These results suggest that normothermic CPB did not increase the incidence of persistent postoperative neurological
dysfunction compared to hypothermic CPB. 相似文献
14.
15.
The study of intratumoral PO2 in brain tumors 总被引:1,自引:0,他引:1
T Kayama A Ogawa Y Sakurai T Wada M Murakami T Yoshimoto J Sukuki 《Brain and nerve》1988,40(4):319-325
The aim of this study was to evaluate the hypoxic cells in the human brain tumor in vivo. Untreated 16 cases of brain tumor were analysed. During the surgery for the purpose of removal of the tumor, needle type-O2 sensors were inserted into femoral artery and in brain tumor to measure PaO2 and intratumoral O2 pressure. A plate type O2 sensor was put on the surface of surrounding brain cortex to measure cortical O2 pressure. These O2 sensors for this study is able to measure O2 pressure continuously and to observe these three O2 pressure simultaneously. Operations were performed endotracheal anesthesia under inhalation of ethrane with maintaining systolic blood pressure 120 mmHg. Setting the rate of O2 and N2O gas inhalation 1/3, PaO2 revealed about 110 mmHg which is similar value as physiological state--1 ATM, air inhalation--. The value of TuO2 and BrO2 were revealed 15.3 +/- 2.3 (mean +/- SE) mmHg and 59.8 +/- 6.5 (mean +/- SE) mmHg. According to these results, it might be said that hypoxic fraction surely exist intratumoral tissue. It is also well known that O2 removes from higher pressure zone to lower pressure zone after O2 was diffused from red blood cell in brain tissue. It might be also mentioned that much lower hypoxic fraction than the value of this study is existing intratumoral tissue. It has long been recognized that hypoxia influences the response of cells and tissues to radiation. However, they have been suspected on the basis of experimental data in vitro. This study showed hypoxic fraction in human brain tumor tissue in vivo.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
16.
Bifrontal interhemispheric approach to aneurysms of the anterior communicating artery 总被引:1,自引:0,他引:1
The authors review their experience with the bifrontal interhemispheric approach in 603 cases of single anterior communicating artery (ACoA) aneurysms and describe the operative technique. With this approach, the olfactory tracts are dissected, and both A1 segments of the anterior cerebral arteries are identified subfrontally. The interhemispheric fissure is then dissected and A2 segments are followed from the distal portion toward the ACoA complex. Following the administration of a combination of mannitol, vitamin E, and dexamethasone, a temporary clip is placed on at least the dominant A1 segment prior to dissection of the aneurysm itself. Once the aneurysm has been completely freed from the surrounding structures, the neck is ligated and clipped. If the aneurysm ruptures during surgery, temporary clips are placed on both A1 and A2 segments bilaterally and the operation proceeds in a completely dry field. With this method, it is possible to occlude any of the intracranial vessels for up to 40 minutes within 100 minutes of drug administration. To prevent the possibility of rerupture and the development of vasospasm in the period before aneurysm surgery, the authors have adopted a policy of performing ultra-early operations within 48 hours of the onset of symptoms. Among the 257 cases operated on during the 9 years since 1975, one-fifth have been operated on within 48 hours of rupture, and the in-hospital mortality rate has been only 4.3% (11 cases). Follow-up studies have shown that 87% of the 246 surviving patients have returned to useful lives. 相似文献
17.
Hiroo Takehara M.D. Akira Okada M.D. Masaharu Nishi M.D. Katsuhiro Masamune M.D. 《Pediatrics international》1992,34(5):569-572
We present a case of Peutz-Jegher's syndrome in an 18 year old female who was followed for gastrointestinal polyps for 13 years from the age of 5 years. The patient was treated four times with surgical or endoscopic polypectomy for gastrointestinal polyps. At the age of 14 years, a combined surgical and endoscopic approach for the management of Peutz-Jegher's syndrome was carried out. A large polyp of the ileum required enterotomy for its removal, and another smaller polyp of the upper jejunum was identified and removed by intra-operative total enteroscopy via the anus. Intra-operative enteroscopy allows one to identify polyps that would previously have been missed. A more complete polypectomy can be performed using this technique, allowing the patient with Peutz-Jegher's syndrome a longer interval between laparotomies and a reduction in symptoms attributed to polyps. 相似文献
18.
Teruo Iwasaki Katsuhiro Nakagawa Motoaki Yasukawa Hiroyuki Shiono Teruaki Nagano Kunimitsu Kawahara 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2006,54(1):35-39
Ectopic cervical or cervico-mediastinal thymomas are very rare and most of them are asymptomatic, except for the presence
of a cervical mass. We present the case of a 71-year-old man with an ectopic cervico-mediastinal thymoma threatening superior
vena cava syndrome. He had a slight headache and presented with venous dilatation on the chest wall. A computed tomographic
scan and magnetic resonance, imaging of the chest demonstrated a mass extending from the right neck to the hilum, that indented
the trachea and compressed and displaced the brachiocephalic veins anteriorly. Under a right hemicollar incision and median
sternotomy, the mass was resected en bloc together with the thymus. The resected specimen was an encapsulated mass measuring 11×7×4 cm. The pathological diagnosis
was type AB, non-invasive thymoma, confirmed by 3-color flow, cytometry of tumor-derived lymphocytes. Flow cytometry using
biopsy material may contribute to the preoperative diagnosis of ectopic thymoma. 相似文献
19.
Manuel E. Zeledon R. Yukio Ando Katsuhiro Asonuma Masaaki Nakamura Xuguo Sun Mitsuharu Ueda Junko Fujii Yukihiro Inomata 《Transplant international》2006,19(3):233-238
Liver transplantation, which serves as treatment of familial amyloidotic polyneuropathy (FAP), and domino liver transplantation, which utilizes resected livers from patients with FAP for treatment of liver diseases, may induce changes in transthyretin (TTR), a pathogenic FAP-related protein. To evaluate this possibility, we performed a 70% hepatectomy or administered tacrolimus to Dark Agouti (DA) rats for 7 days and then measured changes in liver TTR mRNA levels and changes in serum TTR concentrations. After hepatectomy, TTR mRNA levels decreased by 77%; at day 3, they returned to preoperative levels. Except for slightly elevated serum TTR concentrations 12 h after operation, serum TTR levels remained unchanged. Thus, partial hepatectomy did not influence serum TTR concentrations. After tacrolimus administration, TTR mRNA declined by 56% 12 h after the experiment started; however, after day 3, a rebound phenomenon occurred until day 7. Tacrolimus may facilitate serum TTR degradation, although production of TTR in the liver also increased. This finding -- that TTR, the source of FAP-inducing amyloid, did not increase after transplantation -- may help post-transplantation treatment of patients who have FAP and other liver diseases. 相似文献