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This study was undertaken into rats to investigate changes in the hepatic lymph vessels and the space of Disse in endotoxaemia and to examine their relationship with the development of endotoxin-induced hepatic injury. Lymph stasis, namely dilatation of the lymph vessels and oedema, developed rapidly in the medium-sized portal canals, the large portal canals, and the liver hilum after endotoxin injection, but not in the small portal canals. Such changes reached their maximum 4-8 h after endotoxin injection and had recovered markedly by 16 h after the injection. The space of Disse remained within normal limits during this period. These findings suggest that the intrahepatic lymph stasis in endotoxaemia may be caused by a reduction in the pumping activity of the extrahepatic and the intrahepatic large lymph vessels rather than by an increase of lymph formation in the liver lobules. There was no evidence suggesting a direct relationship between the disturbance of hepatic lymph flow and the development of hepatic injury in endotoxaemia. 相似文献
13.
G Tanaka J Shojima I Matsushita H Nagai A Kurashima K Nakata E Toyota N Kobayashi K Kudo N Keicho 《The European respiratory journal》2007,30(1):90-96
The present study aimed to elucidate risk factors for nonimmunocompromised pulmonary Mycobacterium avium complex (MAC) infection. Epidemiological data and variations of candidate genes for mycobacterial diseases were analysed in 111 patients with pulmonary MAC infection. Four polymorphisms of the human natural resistance-associated macrophage protein (NRAMP)1 gene, the 5'(GT)n, 469+14 G/C, D543N and the 3'untranslated region (3'TGTG) insertion/deletion, were genotyped using PCR-based methods. Fok I and Taq I polymorphisms of the vitamin D receptor gene and -221 X/Y and codon 54 A/B polymorphisms of the mannose binding lectin gene were also evaluated. Females were more susceptible to MAC infection mainly affecting the right middle lobe or lingular segment of the lung. Patients' residence at the onset of the disease was distributed evenly irrespective of a waterfront or city water supply system. As compared with homozygotes for major alleles of the D543N and TGTG insertion/deletion polymorphism of the NRAMP1 gene, heterozygotes containing minor alleles were less often observed in MAC cases than in controls. This genetic effect was more significant in patients without comorbidity but not in patients with comorbidity. Other polymorphisms did not show any association with the MAC infection. The human natural resistance-associated macrophage protein 1 gene might be involved in susceptibility to pulmonary Mycobacterium avium complex infection. 相似文献
14.
Takashi Murakami Hitoshi Horigome Kiyoji Tanaka Yoshio Nakata Yasutomi Katayama Akira Matsui 《Blood coagulation & fibrinolysis》2007,18(5):389-394
Obesity is a risk factor for cardiovascular disease and thromboembolic events. We investigated the effects of weight reduction by a 12-week calorie-restricted diet with or without aerobic exercise (diet group and diet plus exercise group) on leptin and anticoagulation proteins levels. Forty-two obese nondiabetic individuals were evaluated for blood levels of leptin, protein C activity, free protein S antigen and for body fat area calculated on computerized tomography before and after intervention. Before intervention, serum levels of leptin and free protein S antigen correlated positively with several adiposity-related parameters. After the program, body weight and fat area were significantly decreased in both groups. Body mass index and leptin levels decreased in both groups, with a larger change in the diet plus exercise group than in the diet group. Although protein C activity levels did not change in both groups, free protein S antigen levels decreased significantly in the diet plus exercise group. In conclusion, the 12-week programs had significant effects on the initial weight reduction and body fat mass, decreasing lepin levels in obese nondiabetic individuals. To clarify whether aerobic exercise has additional or direct effects on the anticoagulation system, a study in a large number of individuals is needed. 相似文献
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Aim: This study aims to establish a pressure ulcers model that visualizes the microcirculation, and to examine the participation of ischemia‐reperfusion injury in the pathophysiology of pressure ulcers.
Methods: An original system composed of a new skinfold chamber and compression device allowed loading quantitative vertical stress to the skin. An intravital microscopic technique enabled direct visualization of the microcirculation in the physiological condition and in response to pressure application. To estimate the effect of ischemia‐reperfusion injury, animals were divided into two groups: the compression‐release group in which the animals received four cycles of compression‐release which consisted of 2 hours of compression followed by 1 hour of pressure release; and the compression alone group in which the animals underwent continuous compression for 8 hours. Functional capillary density was quantified before the compression procedure and on day1 (35 hours) after the first evaluation.
Results and Conclusions: The cyclic compression‐release procedure significantly decreased functional capillary density as compared to continuous compression, indicating that in our experimental setting repetition of ischemia‐reperfusion cycle more severely damaged the microcirculation than single prolonged ischemic insult. The finding supports the significant contribution of ischemia‐reperfusion injury to the pathophysiology of pressure ulcers at the level of dynamic in vivo microcirculation. 相似文献
Methods: An original system composed of a new skinfold chamber and compression device allowed loading quantitative vertical stress to the skin. An intravital microscopic technique enabled direct visualization of the microcirculation in the physiological condition and in response to pressure application. To estimate the effect of ischemia‐reperfusion injury, animals were divided into two groups: the compression‐release group in which the animals received four cycles of compression‐release which consisted of 2 hours of compression followed by 1 hour of pressure release; and the compression alone group in which the animals underwent continuous compression for 8 hours. Functional capillary density was quantified before the compression procedure and on day1 (35 hours) after the first evaluation.
Results and Conclusions: The cyclic compression‐release procedure significantly decreased functional capillary density as compared to continuous compression, indicating that in our experimental setting repetition of ischemia‐reperfusion cycle more severely damaged the microcirculation than single prolonged ischemic insult. The finding supports the significant contribution of ischemia‐reperfusion injury to the pathophysiology of pressure ulcers at the level of dynamic in vivo microcirculation. 相似文献
17.
Verbal Working Memory and Atherosclerosis in Patients with Cardiovascular Disease: An fMRI study 总被引:1,自引:0,他引:1
Andreana P. Haley PhD Lawrence H. Sweet PhD John Gunstad PhD Daniel E. Forman MD Athena Poppas MD Robert H. Paul PhD David F. Tate PhD Ronald A. Cohen PhD 《Journal of neuroimaging》2007,17(3):227-233
BACKGROUND AND PURPOSE: Intimal-medial thickening (IMT) of the carotid wall is an accepted peripheral marker of atherosclerosis. It is associated with increased risk for myocardial infarction and stroke, and lower attention-executive-psychomotor functioning. The purpose of this study was to examine the relationship between IMT and brain activity during a verbal working memory (VWM) task in patients with cardiovascular disease (CVD). METHODS: Thirteen CVD patients underwent functional magnetic resonance imaging (fMRI) during a 2-Back VWM task, and B-mode ultrasound of the carotid arteries. IMT was calculated using an automated algorithm based on a validated edge-detection technique. The relationship between IMT and 2-Back-related brain activity was modeled using partial correlations controlling for age and small vessel disease as measured by white matter signal hyperintensities on MRI (WMH). RESULTS: Higher IMT was associated with lower 2-Back-related signal intensity and in the right middle frontal gyrus, independent of age and WMH. CONCLUSIONS: IMT may be one mechanism contributing to brain dysfunction in CVD. The blood oxygenation level-dependent (BOLD) contrast appears to be highly sensitive to peripheral vascular health as measured by IMT. Future studies should examine the sensitivity and specificity of the BOLD response for predicting cognitive decline in CVD. 相似文献
18.
Y. Watanabe M. Sato T. Lee Y. Abe Y. Nakata H. Kashu S. Iseki Y. Mizukami S. Kimura 《HPB surgery》1996,9(2):107-111
A 75-year-old man who was diagnosed as having mucin-producing pancreatic cystic lesion ofthe
main pancreatic duct by duodenoscopic examination was reported. Because of the low
malignant potential of such lesions, duodenum-preserving resection of the head of the pancreas
was performed, and the intra-operative histological examination showed no malig-nancy of the
resected pancreatic head and no other surgical procedures, such as lymph-adenectomy nor
pancreato-duodenectomy were necessary. The significance of this case report lies in that a less
invasive operation should be selected at first to diagnose whether the lesion is malignant or not,
and als0 that the selected operation itself must be sufficient to resect an adequate part of the
pancreatic tissue involving the cystic lesion, ifnot malignant. Here, we report the process to select
the procedure and the surgical technique. 相似文献
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