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961.
To clarify the mechanisms underlying thrombocytosis secondary to infections, we longitudinally studied serum levels of thrombopoietin (TPO) and interleukin (IL)-6 in 15 infants and young children with prominent thrombocytosis (platelets >700 x 10(9)/l) following acute infections and 116 age-matched controls using an enzyme-linked immunosorbent assay. The subjects included nine patients with bacterial infections, three with viral infections and three with non-determined pathogens. TPO values in the controls were 2.24 +/- 0.87 fmol/ml (mean +/- SD) with a 95% reference interval of 0.85-4.47 fmol/ml. In the first week of infection, platelet counts were normal, but TPO values increased (approximately 10.73 fmol/ml). TPO levels peaked on day 4 +/- 2 at 6.44 +/- 2.37 fmol/ml and then fell gradually. When platelet counts peaked in the second and third weeks, TPO levels were similar to the controls. IL-6 levels in the first week rose and dropped more rapidly than TPO. Serum TPO values were significantly correlated with C-reactive protein levels (r = 0.688, P < 0.001) and IL-6 levels (r = 0.481, P = 0.027). These results suggest that TPO contributes to thrombocytosis following infections in conjunction with IL-6, arguing for additional regulatory mechanisms of blood TPO levels.  相似文献   
962.
BACKGROUND: Many patients with acute myocardial infarction will still die after admission. Recent trends in hospital mortality were analyzed to identify aspects that need improvement. METHODS AND RESULTS: A total of 1,247 patients admitted to Kinki University School of Medicine within 24 h of the onset of infarction were analyzed between 1975 and 2001. The percentage of patients discharged with 100% occlusion decreased gradually from 31.3% during 1975-1982 to 2.1% during 1998-2001, while those with 50% stenosis or less gradually increased from 12.5% to 82.5% during the same period (trends: p < 0.01). The cardiac death rate was 17.1% in 1975-1982, and 7.7% in 1998-2001, showing a significant decrease with time (p < 0.01). This decrease was particularly marked among those admitted within 6 h of the onset of infarction. Death due to cardiac rupture decreased significantly with time (p < 0.001). In contrast, the non-cardiac death rate, amounting to 2.2% on average, did not decline. CONCLUSIONS: Cardiac deaths due to acute myocardial infarction have decreased markedly of late. However, patients must be admitted within 6 h of the onset of infarction to benefit from this improvement. More effort should be made to improve the general care of patients in order to reduce the incidence of non-cardiac death.  相似文献   
963.
BACKGROUND: Although the anti-atherosclerotic effects of HMG-CoA reductase inhibitors are well known, their specific effect on saphenous vein grafts after coronary artery bypass graft (CABG) operation is not well documented and has not been studied in Japan, so the aim of the present prospective randomized controlled study involving 27 Japanese institutions was to investigate the effects of pravastatin on the progression of atherosclerosis in such grafts and native coronary arteries after CABG. METHODS AND RESULTS: A total of 303 patients who had undergone CABG were randomly assigned to either the pravastatin group (n =168) or the control group (n = 167). Paired coronary angiograms were obtained at baseline and at the end of 5-year follow-up in 182 (60%) patients. The low-density lipoprotein cholesterol concentration significantly decreased in the pravastatin group from 141.4 mg/dl to 113.7 mg/dl (-19.6%), compared with 141.1 mg/dl to 133.7 mg/dl (-5.2%) in the control group (p < 0.001). Although there was no significant difference in the quantitative coronary angiography measurements between the 2 groups, the global change score indicated a significant pravastatin-mediated reduction in plaque progression (p < 0.01). CONCLUSIONS: Pravastatin can potentially reduce atherosclerotic progression in both the bypass graft and native coronary arteries of patients after CABG.  相似文献   
964.
Cholesterol crystal embolization (CCE) is a complication of atherosclerosis. A 67-year-old Japanese man underwent coronary artery bypass grafting. After the surgery, he underwent coronary angiography via the right femoral artery. Twelve days later, he suddenly developed acalculous cholecystitis and was treated with antibiotics. Gradual deterioration in renal function, purplish discoloration of the distal portion of his toes, and eosinophilia were noted. We performed a skin biopsy and made a diagnosis of CCE. Cilostazol and intravenous heparin improved the symptoms and decreased the creatinine level. We retrospectively studied the clinical features of 36 cases registered with a diagnosis of CCE in the Japanese literature.  相似文献   
965.
We describe the first case of T-cell prolymphocytic leukaemia (T-PLL) in which the peripheral blood cells contained a human T-lymphotropic virus (HTLV) related tax sequence. Serum screening tests for anti-HTLV-I/II antibodies were negative. Polymerase chain reaction disclosed the presence of an HTLV-I tax sequence in the peripheral blood. Other sets of oligonucleotide primers for HTLV-I gag , pol , env and the long terminal repeat regions and for the HTLV-II pol region were negative in the DNA of the cells. Although patients with T-PLL have been reported to be seronegative for HTLV-I, our findings point to the possibility that HTLV-I infection might be involved in the aetiology of at least some cases of T-PLL and that there may be alternative mechanisms involved in HTLV-associated leukaemogenesis.  相似文献   
966.
A 70-year-old woman with gastric cancer was referred to our hospital for further evaluation of a cystic mass in the head of the pancreas. Endoscopic ultrasonography (EUS) showed a mural nodule in the cystic mass. Endoscopic retrograde cholangio pancreatography (ERCP) revealed a cystic lesion with a filling defect caused by obstruction with mucus. Magnetic resonance cholangiopancreatography (MRCP) allowed visualization of the entire configuration of the cystic lesion despite the presence of mucus. Pancreatic juice was positive for K-ras point mutation. Pancreatoduodenectomy was performed, with a diagnosis of intraductal papillary adenoma or adenocarcinoma with gastric cancer. Pancreatography of the resected specimen showed a cystic lesion in the uncinate process, consistent with the MRCP findings. Histological examination revealed an intraductal papillary adenoma. MRCP is very useful for demonstrating the total configuration of cystic lesions and is not impeded by impacted mucin. Nevertheless, because of its lower spatial resolution, this noninvasive modality is of limited value in detecting mural nodules. At present, therefore, surgical indications for cystic lesion of the pancreas should be determined by comprehensively analyzing: size and sequential changes in size of the cyst; presence of mural nodules, cytologic examination for presence of malignant cells, and/or K-ras point mutation in pure pancreatic juice.  相似文献   
967.
Omeprazole markedly inhibits basal and stimulated gastric acid secretion and has the ability to produce hypergastrinemia and hyperplasia of enterochromaffin-like cells in humans. On the other hand, paunotol, an acyclic diterpene alcohol, has been reported to inhibit gastrin release by stimulating endogenous secretin release. We investigated the effect of plaunotol on serum gastrin levels after six to eight weeks of omeprazole (20 mg/day) administration in 22 patients (16 males, 6 females; mean age 52.3, range 36–70 years) with peptic ulcer disease. The patients were randomized to the following two groups: 11 subjects with omerprazole alone (single group) and 11 with omeprazole plus plaunotol (240 mg/day) (combination group) treatment. There were no significant differences between the two groups concerning age, sex, ulcer stage, ulcer history, environmental factors, andHelicobacter pylori (HP) prevalence. After complete drug(s) administration, serum immunoreactive (ir) -gastrin levels increased significantly in the single group (P<0.001) in contrast to the combination group, and plaunotol significantly inhibited hypergastrinemia induced by omeprazole administration (P<0.001). Significant increases in serum ir-calcitonin gene-related peptide concentrations were observed in the combination group compared to the single group (P<0.05). However, there were no significant changes in serum ir-secretin, somatostatin, and vasoactive intestinal polypeptide levels as well as ulcer healing and HP prevalence between the two groups. These findings suggest that plaunotol may suppress hypergastrinemia induced by long-term omeprazole administration, at least partly, via a certain brain-gut hormone affecting gastrin release.  相似文献   
968.
Interferon (IFN)-gamma is produced by T cells and natural killer cells and activates monocytes and dendritic cells (DCs). Recently, IFN-gamma has been shown to be produced by mouse DCs following stimulation with interleukin (IL)-12, which is markedly augmented by the addition of IL-18. We here analyzed whether human DCs secrete IFN-gamma in response to IL-12 and/or IL-18. Human immature DCs, generated from cord blood CD14(+) monocytes by treating with granulocyte-macrophage colony-stimulating factor and IL-4, were incubated with IL-12 and/or IL-18 and assayed for IFN-gamma production. IL-12, but not IL-18, weakly induced IFN-gamma production, while IL-12 together with IL-18 induced high levels of IFN-gamma production. Similar results were obtained with mature DCs, although levels of IFN-gamma production were less than those in immature DCs. Also with mature and immature DCs, IL-12 upregulated the expression of IL-18 receptor alpha (Ralpha), and costimulation with IL-12 and IL-18 upregulated CD40 expression. Anti-IL-18Ralpha antibody abrogated both the IFN-gamma induction and the CD40 upregulation by IL-12 plus IL-18. These findings suggest that IL-12 upregulates IL-18Ralpha expression on human DCs and acts synergistically with IL-18 to induce high levels of IFN-gamma, which subsequently enhances CD40 expression on DCs in an autocrine manner.  相似文献   
969.
Summary We report a case of a papillary fibroelastoma originating from the left ventricular endocardium in the outflow tract which was discovered by echocardiography in an asymptomatic patient. Two echocardiographic features were observed: (1) the tumor surface was smooth, and characteristic papillary formation was not detected; and (2) the outline of the mass was clearly defined as a dense echo, with the central, radiolucent, portion surrounded by a highly refractive linear echo at the level of the maximum diameter of the mass. The excised tumor was covered with a gelatinous substance that masked multiple papillae on the surface, but its echolucent center could not be explained by the pathology of the tumor which was solid centrally. Our case indicates that a papillary fibroelastoma may sometimes show echocardiographic findings similar to those of a myxoma, although other investigators have not noted the smooth surface and the echolucent center makes it indistinguishable from a myxoma. Thus, in some cases, it is difficult to distinguish papillary fibroelastoma from myxoma by echocardiography.  相似文献   
970.
The effects of hypoxia and reoxygenation on regular contractions and postrest contractions (PRC) of papillary muscle of rats were studied. Isometric tension was measured during two cycles of hypoxia and reoxygenation. Trains of 80 externally continuous stimulations at 40/min were applied. PRCs were evoked by a stimulus train after a 60 sec resting interval. After 90 min of hypoxia (the first hypoxia period), regular contractions and PRCs decreased to 5.6 +/- 2.0% and 23.4 +/- 2.4% of baseline values, respectively (p less than 0.001; n = 18). After 90 min of reoxygenation, the recovery of the PRCs (44.4 +/- 3.4%) was better than that of the regular contractions (23.3 +/- 3.3%) (p less than 0.01; n = 18). After 30 min of hypoxia (the second hypoxic period), regular contractions and PRCs decreased to 2.2 +/- 0.6% and 13.6 +/- 1.6% of baseline values, respectively (p less than 0.001; n = 18). However, the recovery from the second hypoxic injury was not significant for either regular contractions or PRCs. The % diastolic tension, which was normalized to the baseline for regular contractions, increased to 113.2 +/- 6.9% and 133.6 +/- 8.4% at the end of the first and the second hypoxic periods, respectively. There was statistically significant correlation between the % diastolic tension and the % hypoxic injury of PRCs (p less than 0.002; n = 18). There was no significant relationship between % diastolic tension and % hypoxic injury of regular contractions. There was no statistically significant correlation between % diastolic tension and % recovery from the hypoxic injury of either regular contractions or PRCs.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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