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1. We previously reported that angiotensin II release from the mesenteric arteries of Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR) increased in a time-dependent manner as a result of the isolation of the arteries and perfusion. This phenomenon appeared to be due to the withdrawal of circulating angiotensin II (AII). 2. The purpose of the present study was to test the hypothesis that vascular AII generation may be negatively regulated by circulating AII in WKY and SHR, and to clarify the role of this vascular angiotensin II in the sustained hypertension of SHR following nephrectomy. 3. The mesenteric arteries from kidney-intact and nephrectomized WKY and SHR were perfused and the amount of AII released into the perfusate was measured. The effects of the angiotensin converting enzyme inhibitor, captopril, and the effects of supplementation of renal renin and circulating angiotensins to nephrectomized rats, by blood exchange between kidney-intact and nephrectomized rats, on AII release were examined to clarify the pathway of vascular AII generation after nephrectomy. 4. Nephrectomy caused augmentation of vascular AII release both in WKY and SHR in spite of the abolishment of circulating renin. Captopril reduced this enhanced release of AII, but blood exchange did not affect it. There was no significant difference in these responses between WKY and SHR. 5. These results suggest that WKY and SHR have in common a potent pathway for production of vascular AII in response to the withdrawal of circulating AII, although this pathway is not responsible for the sustained hypertension of SHR after nephrectomy. The precise pathophysiological role of this pathway remains to be elucidated.  相似文献   
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A 38-year-old female presented with a lower abdominal mass. During the operation the mass was found to be retroperitoneal and was excised. Gross examination revealed a mucin-containing cystic lesion with a mural nodule. On microscopic examination, the cystic areas were lined by an invasive mucinous adenocarcinoma and the nodule was composed of an anaplastic sarcomatoid tumor that was immunoreactive for cytokeratin. This present case is the 21st example of a retroperitoneal primary mucinous cystadenocarcinoma and the fourth with a mural nodule. Three of four cases with a mural nodule, including our case, had a rapidly fatal outcome.  相似文献   
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Summary Acute cerebrovascular congestion after a closed head injury is significantly related to intracranial hypertension. As an indirect method of cerebral blood flow measurement, transcranial doppler sonography (TCD) provides a rapid and noninvasive assessment of cerebral haemodynamics, including hyperaemic conditions.TCD examinations was serially performed in 35 patients with severe head injury with intact cerebral circulation; i.e. the mean flow velocity (MFV) patterns of the middle cerebral artery (MCA) did not show signs of cerebral circulatory arrest such as systolic spike, to and fro, or no flow. The results showed that the MFV of the MCAs and ipsilateral extracranial internal carotid arteries (ICAs) in 9 of these patients increased sharply and pulsatility index (PI) decreased during 48–96 hours after the injury. This was soon followed by patterns of high intracranial resistance, consistent with elevated intracranial pressure (ICP) in monitored patients and acute brain swelling on repeated computed tomographic (CT) scans. The correlation between increased MFVs, decreased PIs, and cerebral haemodynamic changes leading to acute brain swelling is discussed.The number of patients who ended with severe disability, vegetative state, or death was 66% in this group of 9 patients, compared to only 34% for the 35 patients overall with severe head injury. Though the morbidity and mortality rates largely depend on the primary injury, the presence of acute cerebral swelling aggravate the grave course in these patients. And the ability of TCD to monitor the hyperaemic state prior to oedema should lead us to adjust the therapy in order to minimize the secondary insult related to intracranial hypertension.  相似文献   
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Hepatocellular carcinoma (HCC) is often associated with chronic liver disease, such as hepatitis or cirrhosis, and this association may limit the use of surgery as a therapy, and if surgery is pursued, may give rise to postoperative hepatic failure. We evaluated the outcome in patients with HCC given preoperative portal vein embolization (PVE) before they underwent major hepatectomy. After PVE, portal pressure increased significantly. Two weeks after PVE, both the volume of the non-embolized lobe and the 15-min indocyamine green retention rate (ICG R15) were significantly increased. The prognostic score, calculated on the basis of age, ICG R15, and the resection rate, was significantly decreased. The operative mortality rate was significantly lower in patients who underwent PVE before surgery than in patients who did not receive PVE. The cumulative survival rate of the PVE patients, even those with cirrhosis of the liver, was significantly higher. Prior PVE appears to allow more extensive major hepatectomy and to lessen the risk of this invasive surgery. However, patients in whom the portal pressure immediately after PVE was more than 30cm H2O and/or whose prognostic score exceeded 50 points developed postoperative hepatic failure. These features should be kept in mind when it is decided whether surgery is indicated. Nevertheless, preoperative PVE appears to be a beneficial procedure for patients undergoing major hepatectomy, particularly those with chronic liver disease.  相似文献   
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CONTEXT: Health disparities between rural and urban communities are well documented. There are many suggested causes and many proposed solutions but no one-size-fits-all answer. The most successful community interventions have been introduced by communities themselves. However, before communities invest in such interventions, each group must identify and prioritize their needs. PURPOSE: This article describes the Hoshin facilitation method as a practical option assisting communities in assessing their needs and gaining consensus for future steps. METHODS: Thirty-four meetings were held in 11 rural communities in Hawaii using the Hoshin process to identify factors that impact rural health. Themes were identified by constant comparative analysis and thematic frequency described. Commonality of responses between communities was examined. Informal feedback was collected from meeting participants. FINDINGS: There was a great deal of commonality between community responses, with economic factors, drug use, lack of community leadership, lack of health care services and access to services, lack of healthy activities for youth, and poor public education being the most common issues noted. Group involvement in the meetings was high, and the facilitation method received positive feedback from participants. CONCLUSIONS: The Hoshin facilitation method is a very useful tool to help communities rapidly identify and prioritize areas for programmatic attention.  相似文献   
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With the recent advances in DNA sequencing technology, a succession of entire genome sequences have been published. A number of genome projects are underway in pathogenic fungi. From these, we present the history and current status of the genomic analysis of Candida albicans. The sequencing project for this organism has been undertaken at Stanford University, and is now nearing the end.  相似文献   
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