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921.
We report a case of hepatic pseudolymphoma in a 67-year-old woman that was detected during an abdominal sonography screening. The lesion was further evaluated using CT, MRI, angiography, and contrast-enhanced sonography. The imaging features of this tumor are discussed herein. The diagnosis of pseudolymphoma was achieved via sonographically guided biopsy. The lesion regressed completely within 1 year.  相似文献   
922.
Nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) is implicated in immunolog-ical and inflammatory processes. Inflammatory cytokines and endotoxin induce a large amount of NO from various cells. Surgical stress produces cytokines, which leads to systemic inflammatory response syndrome (SIRS). Continuously high production of cytokines causes a variety of complications including pneumonia, intraabdominal abscess and sepsis. We investigated the relationships between the nitrite/nitrate (NOx) concentration and the level of cytokines in 50 patients undergoing gastroenterological surgery. We measured the levels of cytokines, including interleukin-6 (IL-6), tumor necrosis factor- (TNF-) interleukin-1 receptor antagonist (IL- 1ra), and nitrite/nitrate (NOx) concentration in the serum and exudative fluid from the thoracic or abdominal cavity of 50 patients undergoing gastroenterological surgery in order to make clear the relationship between cytokines and NO.NOx levels in the serum of the group with complications were higher on days 3 and 7 than in the group with no complications (P < 0.05). In the complications group, IL-6 was more elevated, and the NOx level was synchronously elevated. In conclusion, surgical stress caused inflammatory cytokinemia. NOx was produced during surgical stress, and when complications occurred, more NOx was produced.  相似文献   
923.
BACKGROUND: Matrix metalloproteinase (MMP) plays an important role in the development of ventricular remodeling in an animal model of acute myocardial infarction (AMI). We examined whether circulating MMP activity can predict left ventricular (LV) remodeling after AMI in humans. METHODS: We measured the circulating level of MMP-2 and MMP-9 activities (gelatinase activity) at 14 days after the onset of AMI by gelatin zymography in 52 consecutive patients (age 62+/-2). All patients underwent direct PTCA and stenting at an acute stage, and were treated subsequently with losartan or enalapril. Biplane left ventriculography was performed at admission, and 2 weeks and 6 months after the onset of AMI. RESULTS: We expressed gelatinolysis activity as the ratio to MMP-2 standard. Mean gelatinase activity was 0.721+/-0.013. We divided patients into two groups, groups with gelatinolysis activity <0.72 (low group, n=27) and >0.72 (high group, n=25). Either change in LV end-diastolic volume index (LVEDVI, ml/m(2)) or end-systolic volume index (LVESVI, ml/m(2)) from admission to 2 weeks was not different between the two groups. Changes in both LVEDVI and LVESVI from 2 weeks to 6 months were greater in high gelatinolysis activity group than those in low activity group. Moreover, circulating level of gelatinolysis activity was positively correlated with changes in LVEDVI and LVESVI from 2 weeks to 6 months. CONCLUSION: These results demonstrate that circulating level of gelatinase activity can predict LV remodeling after AMI. Inhibition of gelatinase activity at the acute phase may be a therapeutic strategy for the prevention of remodeling after AMI.  相似文献   
924.
The effect of alpha-galactosylceramide (alpha-GalCer) on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in mouse peritoneal cells was studied. alpha-GalCer augmented LPS-induced NO production in mouse peritoneal cells, but not in RAW 264.7 macrophage cells. alpha-GalCer augmented NO production, but not tumor necrosis factor (TNF)-alpha production in LPS-stimulated peritoneal cells. Peritoneal cells produced a significant level of interferon (IFN)-gamma in response to alpha-GalCer and anti-IFN-gamma antibody abolished the augmentation of LPS-induced NO production by alpha-GalCer. Moreover, anti-IFN-gamma antibody prevented the enhanced expression of an inducible type of NO synthase mRNA by alpha-GalCer. alpha-GalCer did not augment LPS-induced NO production in peritoneal cells from natural killer T (NKT)-deficient mice. Therefore, it was suggested that alpha-GalCer might augment LPS-induced NO production in peritoneal cells through release of IFN-gamma from NKT cells.  相似文献   
925.
BACKGROUND/AIMS: To elucidate the mechanisms of action of interferon (IFN) against hepatitis C virus (HCV), we studied the serum HCV dynamics of free-virions (FV) and immune-complexes (IC) in patients treated with IFN. METHODS: FV and IC were separated by immunoprecipitation using anti-human immunoglobulin and quantified serially using real-time detection-polymerase chain reaction. RESULTS: Initially [1st phase (0-24 h)], the FV decreased more rapidly compared to IC [exponential decay slope (EDS)=1.78+/-0.42 vs. 0.99+/-0.31 log10/day, P<0.001; half-life=5.65+/-2.02 vs. 12.5+/-2.83 h, P<0.0001], but at the 2nd phase (1-14 days), half-life of FV was significantly longer than that of IC (101+/-117 vs. 14.2+/-1.08 h, P<0.005). Regarding response to IFN, the decline slope was not significantly different at the 1st phase, but at the 2nd phase, the FV-HCV RNA decreased more slowly in non-responders than in sustained responders to IFN (EDS=0.05+/-0.02 vs. 0.34+/-0.19 log10/day, P<0.005; half-life=186+/-112 vs. 15.3+/-1.85 h, P<0.005). CONCLUSIONS: The presence of escape mutants from the neutralizing antibodies may be involved in resistance to IFN. Analyzes of FV- and IC-HCV dynamics are useful for predicting the IFN efficacy and understanding the mechanism of IFN action in chronic hepatitis patients.  相似文献   
926.
927.
The detailed mechanism of NO production in mouse vascular endothelial cells, END-D, was studied. The NO production in END-D cells was triggered by gamma interferon (IFN-gamma), but not LPS. However, LPS augmented the NO production in IFN-gamma-stimulated END-D cells. A high level of NO production was due to the expression of an inducible type of NO synthase (iNOS) in those cells. A significant amount of NO was detected 18 h after IFN-gamma stimulation, accompanied by the delayed iNOS expression. The JAK/STAT signal pathway mediated IFN-gamma-induced NO production, but did not participate in the LPS-induced augmentation. Further, no activation of nuclear factor (NF)-kappaB was involved in the NO production in END-D cells stimulated with either IFN-gamma and/or LPS. The mechanism of NO production in END-D cells was suggested to be different from that in mouse macrophages. The differential regulation of NO production in mouse vascular endothelial cells and macrophages is discussed.  相似文献   
928.
This study examined whether coronary flow reserve (CFR) measured immediately after primary coronary stenting could predict wall motion recovery in patients who have acute myocardial infarction. CFR significantly correlated with the change of wall motion score (r = 0.68, p <0.0001), and the optimal cut-off value of CFR for predicting wall motion recovery was 1.4 (sensitivity 85%, specificity 94%).  相似文献   
929.
930.
Inflatable penile prostheses are a common treatment for erectile dysfunction that is unresponsive to less-invasive measures. Complications can arise at the time of the placement of the prosthesis or at a later date. Complications may be related to infection and/or mechanical failure of one or more of the prosthesis components including cylinder, reservoir, pump, and tubing. Mechanical failure includes kinking, migration, and aneurysmal dilation of the cylinder, erosion of the tunica albuginea of the corpora cavernosum by the cylinder, disconnection of the tubing, and migration of the reservoir. MRI of the entire components with the cylinders in both flaccid and inflated states is the best imaging modality available to image patients with suspected implant complications.  相似文献   
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