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The migration of leukocytes into inflamed peripheral tissues and lymphoid organs involves a cascade of molecular events finely regulated by cell adhesion molecules and chemokines. Fractalkine/CX3CL1 is a membrane-bound chemokine that functions not only as a chemoattractant but also as an adhesion molecule, and is expressed on endothelial cells activated by proinflammatory cytokines. The fractalkine receptor, CX3CR1, is expressed on cytotoxic effector lymphocytes including NK cells and cytotoxic effector T cells (T(CE)), mature monocytes/macrophages, and mucosal dendritic cells, all of which play important roles in elimination of pathogens and cancer cells. Recently, accumulating evidence in both clinical studies and animal disease models has shown that fractalkine is also involved in the pathogenesis of various chronic inflammatory diseases, such as rheumatoid arthritis and atherosclerosis. This article reviews the unique functions of fractalkine and its pathophysiological roles in various clinical conditions.  相似文献   
13.
Abstract: A prospective study was performed to determine whether low-density lipoprotein (LDL) apheresis, when performed only immediately before and after percutaneous transluminal coronary angioplasty (PTCA), is effective in preventing restenosis of coronary artery lesions following PTCA. Thirty-six patients with coronary heart disease (CHD) and hypercholesterolemia were divided into 2 groups. The 9 patients in the LDL group underwent LDL-apheresis 1 day before and 5 days after PTCA while the 27 patients of the control group underwent PTCA but did not undergo LDL-apheresis. Follow-up coronary angiography (CAG) was performed 4 months after PTCA. The rate of restenosis of coronary artery lesions was significantly lower in the LDL group (0%) than in the control group (30%). These findings suggest that LDL-apheresis, when performed before and after PTCA, is effective in preventing restenosis of coronary artery lesions in patients with CHD and hypercholesterolemia.  相似文献   
14.
The effect of the hepatic energy status on the development of posttraumatic jaundice (PTJ) was studied to clarify the mechanism of PTJ. Fifty-four patients with severe torso injury who were expected to develop PTJ on admission with an average Injury Severity Score of 27 were selected for this study. They were retrospectively divided into three groups according to their maximum bilirubin concentration by day 10: group H, 12 patients with marked elevation of serum bilirubin (>8 g/dl); group L, 23 with mild bilirubinemia (2–8 g/dl); and group N, 19 with no bilirubinemia (<2 g/dl). Group H patients, in whom trauma-related shock was severe and prolonged, developed severe hyperbilirubinemia, and their arterial ketone body ratio (AKBR), which reflects the hepatic mitochondrial redox state and is closely correlated to its energy production, was significantly lower throughout the first week. In contrast, the AKBR increased to an above normal level, indicating enhanced energy production in groups N and L. The serum direct/total bilirubin was also higher in group H. The abnormal hepatic energy metabolism is considered to have reduced the excretion of conjugated bilirubin from the hepatocytes into the bile canaliculi, which is a process that has to proceed against the bilirubin concentration gradient. The subsequent diffusion of the accumulated water-soluble conjugated bilirubin in hepatocytes into the blood is thus considered to be one of the causes of PTJ.  相似文献   
15.
We report the case of an infant with a cerebellar astrocytoma that showed marked calcification within only 6 months. In general, only slow-growing tumors tend to calcify. To our knowledge, no other case of such rapid calcification in cerebellar astrocytoma has been reported.  相似文献   
16.
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   
17.
The findings in twenty-two patients with insulinoma were reviewed, as continuous efforts should be made to establish preoperative localization of the tumor. Superselective arteriography and percutaneous, transhepatic portal vein and pancreatic venous catheterization are highly recommended approaches. At the time of surgical intervention, a cautious exploration of the pancreas after thorough mobilization is most important. Recent use of intraoperative ultrasonography increases the likelihood of finding these occult tumors which locate deeply in the head of the pancreas. Apart from the diagnostic problems, we wish to emphasize the high incidence of malignancy (7/22, 31.8 per cent) in our series. Althout patients with malignant isulinoma had a much better prognosis compared to those with a pancreatic ductal malignancy, pancreatic resection with regional lymphnode dissection seems to be a rational procedure. Enucleation can be done when intraoperative findings of the tumor and regional lymphonode indicate no malignant features and no multiple lesions. However, at the first operation, enucleation is still a procedure of choice, even for the malignant insulinoma in the head with a well-defined capsule and no metastatic lesions, the objective being to avoid a duodenopancreatectomy or total pancreatectomy. These data were reported at the 30th Congress of Société Internationale de Chirurgie, Hamburg, Germany, 1983  相似文献   
18.
Endoscopic submucosal dissection (ESD) for colorectal cancer is not widely accepted because of its technical difficulty and the risk of perforation. In addition, the risk of peritonitis cannot be completely eliminated even if a perforation is closed successfully. Reported here are two cases of early colon cancer in which the patients sustained iatrogenic perforations of the ascending colon during conventional endoscopic mucosal resection and of the sigmoid colon during ESD, respectively, requiring abdominal decompression with an 18 G Medicut needle. Both of these perforations were successfully treated by endoscopic clipping. In conclusion, conservative medical management may be possible in patients who have undergone successful closure of colonic perforations using endoscopic clipping. In order to perform immediate endoscopic closure, abdominal decompression has been useful to decrease patient discomfort and colonic lumen collapse. Now, CO2 insufflation is being used effectively for the prevention of pneumoperitoneum.  相似文献   
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20.
We examined a gene polymorphism of a novel Z-disc-related protein, myospryn (cardiomyopathy-associated 5). We focused on one haplotype block associated with a tag single nucleotide polymorphism (SNP) that covered 16 of 27 coding SNPs with linkage disequilibrium (minor allele frequency 0.413). Screening a myospryn polymorphism (K2906N) in a general health check-up of a rural Japanese population revealed an association with cardiac diseases (p=0.0082). In further analysis of the interaction between K2906N and cardiac function in patients, K2906N was associated with the anteroseptal wall thickness of the left ventricle in a recessive model (p=0.0324) and with the ratio of the peak velocity of the early diastolic filling wave to the peak velocity of atrial filling (A/E) (p=0.0278). In an association study based on left ventricular wall thickness, we found a significant difference in the K2906N genotype between controls and patients with cardiac hypertrophy. These results suggest that the K2906N polymorphism could be clinically associated with left ventricular hypertrophy and diastolic dysfunction independent of known parameters. Although the precise mechanism underlying this association remains to be elucidated, treatment with angiotensin II induced an increase in heart myospryn mRNA level in vitro and in vivo. Our results suggest that the polymorphism of myospryn is associated with left ventricular hypertrophy, and an association between a Z-disc protein and cardiac adaptation in response to pressure overload.  相似文献   
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