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61.
Pure neuronal and mixed neuronal-glial tumors of the central nervous system are uncommon but fascinating because they are less aggressive than the more common glial tumors and their prognosis is excellent. Neurologic manifestations are varied and include seizures, symptoms of increased intracranial pressure, and neurologic deficits according to tumor location. Many neuronal tumors of the central nervous system demonstrate characteristic radiologic findings. At magnetic resonance (MR) imaging, gangliocytomas demonstrate low signal intensity on T1-weighted images, high signal intensity on T2-weighted images, and frequent enhancement on gadolinium-enhanced T1-weighted images. Characteristic MR imaging findings of Lhermitte-Duclos disease are a nonenhancing mass in a cerebellar hemisphere with a striated pattern. Central neurocytomas are typically located in the lateral ventricles near the foramen of Monro with a characteristic attachment to the septum pellucidum. Ganglioneurocytoma is a rare variant of central neurocytoma that is characterized by differentiation toward ganglion cells. In ganglioglioma, a well-defined cystic mass with a solid mural nodule is typically seen. Extension of enhancement to the leptomeninges is characteristic of desmoplastic infantile ganglioglioma and correlates with the firm dural attachment of the solid component. Dysembryoplastic neuroepithelial tumor has a well-demarcated, multilobulated or gyriform appearance.  相似文献   
62.
Whitin  JC; Ryan  DH; Cohen  HJ 《Blood》1985,66(5):1182-1188
A modified zymosan preparation was used to probe the interaction of particulate stimuli with human neutrophils (PMNs). After extraction with alkali and detergent, the zymosan particles retained their ability to be opsonized in serum and to stimulate PMNs. Serum-treated zymosan (STZ) induced dose-dependent superoxide (O2-) production and membrane potential depolarization in the range of 1 to 10 mg/mL of STZ. The rate and extent of secretion of lysozyme and beta-glucuronidase were also dose-dependent in the range of 1 to 10 mg/mL of STZ. Cytochemical studies using nitroblue tetrazolium, however, showed that 92% of PMNs were stimulated to produce O2- at 0.1 mg/mL of STZ. The dose response of O2- production induced by STZ is therefore due to increasing O2- production by individual PMNs and not to the stimulation of more PMNs to produce O2-. Evidence for O2- production was found only in the area of PMN-zymosan contact, suggesting a mechanism for the graded responses of PMNs treated with particulate stimuli. In order to determine the nature of the dose dependence of depolarization (a measure of PMN activation), PMNs equilibrated with the fluorescent probe 3,3'- dipentyloxacarbocyanine were analyzed by flow cytometry. The results demonstrate that STZ induces a dose-dependent depolarization of the membrane potential of individual PMNs. These results also demonstrate that increasing concentrations of STZ can induce increasing PMN responses even when all of the PMNs have been activated. These results are consistent with the hypothesis that receptor-mediated particulate stimulation of PMNs is a phenomenon that results in graded PMN responses.  相似文献   
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64.
Between February 1997 and December 2001, 311 adult-to-adult living donor liver transplants (A-A LDLTs) were performed at the Asan Medical Center for patients above 20 years of age. Indications for A-A LDLT were: chronic hepatitis B (203), chronic hepatitis C (5), hepatocellular carcinoma (64), alcoholic cirrhosis (9), cryptogenic cirrhosis (4), secondary biliary cirrhosis (5), primary biliary cirrhosis (1), Wilson' s disease (2), autoimmune hepatitis (1), hepatic tuberculosis (1), cholangiocarcinoma (1), fulminant hepatic failure (14) and primary non-function of cadaveric liver graft (1). Of 311 A-A LDLTs, 36 were of medical high urgency, 20 were for acute and subacute hepatic failure, 15 were for hepato-renal syndrome and 1 was for primary non-function. Recipient age ranged from 27 to 64 years. Donor age ranged from 16 to 62 years. There was no donor mortality. Implanted liver grafts were categorized into seven types: 175 modified right lobe (MRL), 70 left lobe, 32 right lobe, 20 dual grafts, 10 left lobe plus caudate lobe, three extended right lobe and one posterior segment. In MRL, the tributaries of the middle hepatic vein were reconstructed by interpositioning a vein graft. Indication for dual graft implantation was the same as single graft A-A LDLT, and four of 20 were emergency cases. Of 20 dual grafts, 14 received two left lobes, four received a left lobe and a lateral segment, one received a right lobe and a left lobe and one received a lateral segment and a posterior segment. Graft volume ranged from 28% to 83% of the standard liver volume of the recipients. There were 33 (10.6%) in-hospital mortalities (< 4 months) among the 310 patients after 311 A-A LDLTs. Of the 36 patients receiving emergency transplants, 31 survived. These encouraging results justify the expansion of A-A LDLT in coping with increasing demands, even in urgent situations. We have aimed to introduce the establishment of the efficacy of A-A LDLT in various end-stage chronic and acute liver diseases, as well as new technical advances to overcome small graft-size syndrome by using dual-graft implantation and MRL, both of which were first developed in our department.  相似文献   
65.
Plastic surgeons commonly encounter patients with facial lacerations and/or abrasions in the emergency room. If they are properly treated, facial wounds generally heal well without complications. However, infection can sometimes cause delayed wound healing. We performed wound culture for the early detection of infection and to promote the healing of infected facial wounds. We included 5033 patients with facial wounds who visited the emergency room of Kangnam Sacred Heart Hospital between January 2018 and February 2021. Among them, 104 patients underwent wound culture. We analysed the pathogens isolated and the patients' age, sex, wound site, mechanism of injury, wound healing time, time from injury to culture, time to culture results, and dressing methods used. Pathogens were isolated in slightly less than half of the patients (38.46%); among them, Staphylococcus epidermidis was the most common (47.5%). Methicillin-resistant coagulase-negative staphylococci were isolated in six (15%) patients. Patients with complicated wounds had a longer mean wound healing time (10.83 ± 5.91 days) than those with non-complicated wounds (6.06 ± 1.68 days). Wound culture of complicated facial wounds resulted in the isolation of various types of pathogens, including antibiotic-resistant bacteria and fungi. We recommend the use of wound culture for early detection of infection to prevent delayed wound healing.  相似文献   
66.
BACKGROUND: Particulate air pollution has been associated with increased cardiovascular deaths and hospital admissions. To help understand the mechanisms, the types of particles most involved, and the types of persons most susceptible, the association between exposure to summertime air pollution and heart rate variability (HRV) was examined in a panel study of 28 elderly subjects. METHODS: Subjects were seen once a week for up to 12 weeks and HRV (SDNN, r-MSSD, PNN50, low frequency/high frequency ratio (LFHFR)) was measured for approximately 30 minutes at each session using a defined protocol. Temperature, day of the week, and hour of the day were controlled, and dummy variables for each subject were controlled for subject specific risk factors. RESULTS: PM2.5 was associated with r-MSSD (-10.1% change for an interquartile range (IQR) increase in exposure (95% CI -2.8 to -16.9)) and PNN50, but stronger associations were seen with black carbon, an indicator of traffic particles, which was also associated with SDNN (-4.6% per IQR (95% CI -2.0 to -7.2)) and LFHFR. Secondary particles were more weakly associated with r-MSSD, as was ozone. No associations were seen with SO2 or NO2. CO had similar patterns of association to black carbon, which disappeared after controlling for black carbon. Black carbon had a substantially higher effect on SDNN in subjects who had had a previous myocardial infarction (-12.7%, 95% CI -5.7 to -19.25). CONCLUSIONS: Particles, especially from traffic, are associated with disturbances of autonomic control of the heart.  相似文献   
67.
Kim DH  Lee NY  Sohn SK  Baek JH  Kim JG  Suh JS  Lee KB  Shin IH 《Transplantation》2005,79(11):1615-1622
BACKGROUND: The current study attempted to evaluate the association between IL-10 promoter gene polymorphism and transplant outcomes including the occurrence of chronic graft-versus-host disease (GVHD) and its clinical course during systemic immunosuppressive treatment (IST) among 60 recipients of cytokine-mobilized peripheral blood stem cell (PBSC) from HLA-matched sibling donors. METHODS: We analyzed 3 single-nucleotide polymorphisms in proximal region of IL-10 promoter gene (-1082/-819/-592). RESULTS: In the current study, only two haplotypes (1082*A/819*T/592*A [ATA] and 1082*A/819*C/592*C [ACC]) were found. An increased occurrence of chronic GVHD was noted dependent on the IL-10 haplotypes (43% vs. 68% vs. 96% in ACC/ACC vs. ATA/ACC vs. ATA/ATA haplotype, P=0.003). In a logistic regression based on multinomial model, ATA/ATA homozygote had 7-fold increasing risk of the development of chronic GVHD compared with ACC/ACC homozygote. The incidence of chronic GVHD at 1 year was 46%+/-20%, 64%+/-10%, and 82%+/-5% in ACC/ACC, ATA/ACC and ATA/ATA group, respectively (P=0.0266). Plus, the duration of systemic IST was significantly shorter in recipients without ATA-haplotype comparing with those with ATA haplotype (339 days vs. 1,146 days, P=0.0091). CONCLUSION: IL-10 promoter gene polymorphism was found to be apparently associated with chronic GVHD after allogeneic peripheral blood stem cell transplantation from HLA-matched sibling donors.  相似文献   
68.
Generalized low bone mass and osteopenia in both axial and peripheral skeletons have been reported in adolescent idiopathic scoliosis (AIS). However, the mechanism and causes of bone loss in AIS have not been identified. Therefore, this study examined the relationship between the osteogenic and adipogenic differentiation abilities of mesenchymal stem cells (MSCs) and bone mass in 19 patients with AIS and compared these with those of 16 age- and gender-matched patients with lower leg fracture. Mean lumbar spinal bone mineral density (LSBMD) in AIS patients was found to be lower than in controls (P = 0.037) and the osteogenic differentiation abilities and alkaline phosphatase activities of MSCs from patients were also found to be lower than those of controls (P = 0.0073 and P = 0.001, respectively), but the abilities of the MSCs of patients and controls to undergo adipogenic differentiation were similar. The osteogenic differentiation ability was found to be positively correlated with alkaline phosphatase activity in the AIS group. However, the osteogenic and adipogenic abilities were not found to be correlated with LSBMD in either patients or controls. These findings suggest that the decreased osteogenic differentiation ability of MSCs might be one of the possible mechanisms leading to low bone mass in AIS. However, we did not determine definite mechanisms of low bone mass in AIS. Therefore, further study with large scale will be needed to identify the mechanism involved.  相似文献   
69.
Introduction In the proximal femoral metaphysis, hematopoietic marrow is predominant during the adult stage of life. The conversion of hematopoietic marrow to fatty marrow in the proximal femoral metaphysis has been suggested as an etiologic factor of ischemia in the pathogenesis of femoral head osteonecrosis. To determine whether the chronology of fatty marrow conversion of the proximal femoral metaphysis is related to transient bone marrow edema syndrome of the hip, a case control study was conducted on 10 patients with the disease.Materials and methods There were 8 men and 2 women with a mean age of 33 years (range 19–45 years). The 10 patients were matched with 20 controls for gender and age (5-year range). T1-weighted MRI scans of their hips were reviewed. Marrow of the greater trochanter becomes fatty before puberty, and thus, the greater trochanter can be used as a built-in control. The signal intensity of the proximal femoral metaphysis was compared to that of the greater trochanter.Results In all patients, the signal intensity of the proximal femoral metaphysis was isointense (fatty marrow) relative to that of the greater trochanter. In control subjects, the signal intensity was isointense in 8 (40%) and hypointense (hematopoietic marrow) in 12 (60%) (p<0.05).Conclusion The current study shows that the proximal femoral metaphysis is predominantly fatty in transient bone marrow edema syndrome. The conversion of hematopoietic to fatty marrow is known to correlate with decreases in intramedullary blood flow. Thus, the current study suggests that an ischemia of the proximal femur secondary to fatty marrow conversion of the proximal femoral metaphysis might be a cause of transient bone marrow edema syndrome of the hip.  相似文献   
70.
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