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排序方式: 共有455条查询结果,搜索用时 15 毫秒
91.
92.
U Poddar BR Thapa K Vaiphei KL Rao SK Mitra K Singh 《Archives of disease in childhood》1998,78(3):264-266
The clinical profile, malignant potential, and management of 17 children with juvenile polyposis (more than five juvenile polyps) were evaluated clinically and endoscopically. Colonoscopy and polypectomy were done three weekly until colonic clearance was achieved, and thereafter two yearly. All polyps were subjected to histological examination. Mean age was 7.7 years, with a male preponderance (3:1). Presentation was with rectal bleeding (94%), pallor (65%), stunted growth (53%), and oedema (47%), and the mean (SD) duration of symptoms was 33 (27) months. None had a positive family history or any congenital anomaly. Two children had six polyps up to the transverse colon; the rest had numerous polyps all over the colon. All children had juvenile polyps on histology and 10 (59%) had adenomatous changes (dysplasia). Total colectomy was done in six for intractable symptoms. Colon clearance was achieved in eight after an average 3.4 polypectomy sessions, and three were still on the polypectomy programme. In conclusion, juvenile polyposis is commonly associated with low grade dysplasia. Serial colonoscopic polypectomy is effective but colectomy is required for intractable symptoms and when clearance of the colon is not possible. 相似文献
93.
F Laezza BR Gerber JY Lou MA Kozel H Hartman AM Craig DM Ornitz JM Nerbonne 《The Journal of neuroscience》2007,27(44):12033-12044
Fibroblast growth factor 14 (FGF14) belongs to the intracellular FGF homologous factor subfamily of FGF proteins (iFGFs) that are not secreted and do not activate tyrosine kinase receptors. The iFGFs, however, have been shown to interact with the pore-forming (alpha) subunits of voltage-gated Na+ (Na(v)) channels. The neurological phenotypes seen in Fgf14-/- mice and the identification of an FGF14 missense mutation (FGF14(F145S)) in a Dutch family presenting with cognitive impairment and spinocerebellar ataxia suggest links between FGF14 and neuronal functioning. Here, we demonstrate that the expression of FGF14(F145S) reduces Na(v) alpha subunit expression at the axon initial segment, attenuates Na(v) channel currents, and reduces the excitability of hippocampal neurons. In addition, and in contrast with wild-type FGF14, FGF14(F145S) does not interact directly with Na(v) channel alpha subunits. Rather, FGF14(F145S) associates with wild-type FGF14 and disrupts the interaction between wild-type FGF14 and Na(v) alpha subunits, suggesting that the mutant FGF14(F145S) protein acts as a dominant negative, interfering with the interaction between wild-type FGF14 and Na(v) channel alpha subunits and altering neuronal excitability. 相似文献
94.
95.
V. PÖNITZ T. BRÜGGER‐ANDERSEN D. PRITCHARD H. GRUNDT H. STAINES D. W. T. NILSEN FOR THE RACS STUDY GROUP 《Journal of thrombosis and haemostasis》2009,7(2):277-287
Summary. Background: We assessed the relation between admission levels of activated factor XII type A (XIIaA), and long‐term all‐cause and cardiac mortality and recurrent troponin T (TnT) positive cardiovascular events in a consecutive cohort of 870 patients admitted with a clinically strongly suspected acute coronary syndrome (ACS). Methods and results: After a 24‐month follow‐up period, 138 patients (15.8%) had died and 155 (17.8%) had suffered from a recurrent TnT positive (TnT > 0.05 ng mL?1) event. XIIaA levels were significantly lower in long‐term survivors than in patients who died (22.9 (17.7–32.1) vs. 27.2 (20.0–39.7) pmol L?1 [median, 25 and 75% percentiles], P < 0.001). The unadjusted hazard ratio for death within 2 years in patients with XIIaA in the highest quartile was 2.49 (95% confidence interval (CI), 1.52–4.06) as compared with patients with XIIaA in the lowest quartile. In a stepwise Cox regression model for death within 2 years, XIIaA added prognostic information for all‐cause mortality (HR 2.05; 95% CI, 1.21–3.47) above and beyond age, a history of heart failure, ST‐segment elevation, TnT and B‐type natriuretic peptide (BNP). In the subgroup of patients with an admission TnT ≤ 0.05 ng mL?1, XIIaA provided independent prognostic information for all‐cause mortality (HR 3.88; 95% CI, 1.66–9.08) and for the combined endpoint of death or recurrent TnT positive event (HR 2.46; 95% CI, 1.34–4.50). Conclusion: XIIaA, a recently identified in vivo form of activated factor XII is an independent indicator of long‐term all‐cause mortality in patients admitted with chest pain, providing prognostic information above and beyond conventional risk factors. 相似文献
96.
In vitro characteristics of white cell-reduced single-unit platelet concentrates stored in syringes 总被引:1,自引:0,他引:1
PT Pisciotto ; EL Snyder ; JA Snyder ; S Frattaroli ; SM Hopfer ; HM Rinder ; BR Smith 《Transfusion》1994,34(5):407-411
BACKGROUND: Platelet concentrates (PCs) for premature infants may be subjected to filtration, centrifugation, and various storage conditions before transfusion. STUDY DESIGN AND METHODS: As there are few data on the cumulative effect of these procedures on PCs, platelet properties (including biochemical and functional in vitro assays) were evaluated after the processing of single units of PCs through a 1-unit-capacity high-efficiency white cell (WBC)-reduction filter followed by syringe storage at either 22 or 37 degrees C for 6 hours. Two- and 5-day-old PCs, volume-reduced PCs, and prestorage WBC-reduced PCs were evaluated. RESULTS: WBC filtration consistently resulted in a 3 to 4 log10 reduction in WBCs, with less than 15-percent platelet loss. No adverse effects of platelet function or evidence of increased platelet activation as determined by the percentage of P-selectin positivity were noted. A decrease in pH associated with increased lactate production and consumption of glucose was observed following syringe storage under all conditions tested. Such changes were most pronounced, however, with volume-reduced PCs stored at 37 degrees C (pH 6.31 +/− 0.15, lactate 23.0 +/− 3.06 mmol/L). All pH levels at the end of storage were above the minimum Food and Drug Administration requirement (pH 6.0). CONCLUSION: The in vitro data suggest that single units of PCs can undergo WBC filtration followed by syringe storage for up to 6 hours and still maintain acceptable storage characteristics. The practice of maintaining volume-reduced PCs in syringes for 6 hours at 37 degrees C in isolettes during transfusion should, however, be avoided. 相似文献
97.
Selection of platelets for refractory patients by HLA matching and prospective crossmatching 总被引:2,自引:0,他引:2
G Moroff ; G Garratty ; JM Heal ; BR MacPherson ; D Stroncek ; ST Huang ; W Ho ; LD Petz ; MF Leach ; SS Lennon ; et al. 《Transfusion》1992,32(7):633-640
A multi-site clinical study compared platelets chosen for refractory patients by prospective platelet crossmatching using stored donor platelets and HLA-based selection. Seventy-three patients who were refractory to random-donor platelets received two plateletpheresis components, one chosen by HLA-based criteria and the other by crossmatching. Patients were carefully evaluated to exclude nonimmune factors that could adversely affect transfusion results. Each of the five study sites used a crossmatch procedure with which it had experience. Results from this study indicate the following: 1) The overall rate of successful transfusion was similar when an HLA-based method of donor selection that includes all grades of matching and mismatching was compared to a crossmatch-based method of donor selection. 2) HLA-based selection that restricts recipients to grade A and BU matches was superior to a selection method based upon crossmatching alone. Donor selection based on HLA matching (grades A or BU) was also superior to selection based on any degree of HLA mismatching (grades BX, C, or D). 3) Selection of donors based on HLA-cross-reactive groups (defined by in vitro serologic crossreactivity) was no more successful than that based on grade C and D mismatches and was no more successful than selection by crossmatching alone. 4) Lymphocytotoxic and platelet antibodies were not detected in many of the enrolled patients, even though patients demonstrating nonimmune factors were eliminated from the study. It can be concluded that HLA-compatible (grades A and BU) platelets provide optimal support for refractory patients, but that crossmatch-selected platelets are acceptable as an alternative component. 相似文献
98.
TheFirstWorldChineseCongresofDigestionwasheldinBeijingfromOctober20to22,1998inthebeautifulcapitalcityofBeijing.Thespecificaim... 相似文献
99.
Atlas R Campbell P Cozzarelli NR Curfman G Enquist L Fink G Flanagin A Fletcher J George E Hammes G Heyman D Inglesby T Kaplan S Kennedy D Krug J Levinson RE Marcus E Metzger H Morse SS O'Brien A Onderdonk A Poste G Renault B Rich R Rosengard A Salzberg S Salzburg S Scanlan M Shenk T Tabor H Varmus H Wimmer E Yamamoto K;Journal Editors Authors Group 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(4):1464
100.
We tested whether the in vivo infusion of recombinant, soluble CTLA4 fused with Ig heavy chains, as a surrogate ligand used to block CD28/CTLA4 T-cell costimulation, could prevent efficient T-cell activation and thereby reduce graft-versus-host disease (GVHD). Lethally irradiated B10.BR recipients of major histocompatibility complex disparate C57BL/6 donor grafts received intraperitoneal injections of human CTLA4-Ig (hCTLA4-Ig) or murine CTLA4-Ig (mCTLA4-Ig) in various doses and schedules beginning on day -1 or day 0 of bone marrow transplantation (BMT). In all five experiments, recipients of CTLA4-Ig had a significantly higher actuarial survival rate compared to mice injected with an irrelevant antibody control (L6) or saline alone. Survival rates in recipients of hL6 or PBS were 0% at 29 to 45 days post-BMT. In recipients of CTLA4-Ig, survival rates were as high as 63% mice surviving 3 months post-BMT. However, protection was somewhat variable and recipients of CTLA4-Ig were not GVHD-free by body weight, clinical appearance, and histopathologic examination. There were no significant differences in the survival rates in comparing injection dose, injection duration, or species of CTLA4-Ig (hCTLA4-Ig v mCTLA4- Ig). Splenic and peripheral blood flow cytometry studies of long-term hCTLA4-Ig-injected survivors showed a significant peripheral B-cell and CD4+ T-cell lymphopenia, consistent with GVHD. A kinetic study of splenic reconstitution was performed in mice that received hCTLA4-Ig and showed that mature splenic localized CD8+ T-cell repopulation was not significantly different in recipients of hCTLA4-Ig compared with hL6, despite the significant increase in actuarial survival rate in that experiment. These data suggest that the beneficial effect of hCTLA4-Ig on survival is not mediated by interfering with mature donor- derived T-cell repopulation post-BMT. Neither hCTLA4-Ig nor mCTLA4-Ig interfered with hematopoietic recovery post-BMT. We conclude that CTLA4- Ig (most likely in combination with other agents) may represent an important new modality for GVHD prevention. 相似文献