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排序方式: 共有808条查询结果,搜索用时 12 毫秒
781.
St-Pierre J Miller-Felix I Paradis ME Bergeron J Lamarche B Després JP Gaudet D Vohl MC 《Molecular genetics and metabolism》2003,78(1):31-36
The dyslipidemic state of visceral obesity is characterized by increased plasma triglyceride (TG) levels, low HDL-cholesterol concentrations and alterations in LDL composition and concentration. A functional, non-coding -514C>T single nucleotide polymorphism (SNP) of the hepatic lipase gene (LIPC) has been related to variation in HDL-cholesterol concentrations. OBJECTIVES: To investigate the hypotheses that the LIPC -514C>T polymorphism may be associated with a deteriorated lipoprotein-lipid profile and that environmental factor, such as abdominal obesity, alters this association. METHODS: A total of 235 French-Canadian men from the greater Quebec City area were assigned into three groups on the basis of their LIPC -514C>T SNP, including 149 CC homozygotes, 75 CT heterozygotes, and 11 TT homozygotes. RESULTS: In the present study, the highest values of BMI, waist circumference, and accumulation of visceral adipose tissue (VAT) were observed among TT homozygotes (p<0.05). After adjustment for age and BMI, TT homozygotes still showed higher plasma apolipoprotein (apo) AI and HDL-TG concentrations than the two other groups (p<0.05). When the two genotype groups (CC vs CT/TT) were further divided on the basis of VAT accumulation using a cut-off point of 130 cm(2) (high vs low) it appears that irrespective of the genotype subjects with low VAT had higher HDL(2)-cholesterol concentrations (p<0.0001). However, lean carriers of the T allele had higher plasma HDL(2)-cholesterol levels than lean CC homozygotes. The beneficial effect of the T allele on plasma HDL(2)-cholesterol levels was abolished in the presence of visceral obesity (VAT>130 cm(2)).CONCLUSION: In summary, the presence of visceral obesity attenuates the impact of the LIPC -514C>T polymorphism on plasma HDL(2)-cholesterol levels. 相似文献
782.
Escherichia coli heat-stable enterotoxin: rapid method of purification and some characteristics of the toxin. 总被引:3,自引:3,他引:3 下载免费PDF全文
In this study we used Escherichia coli strain F11(P155) of porcine origin. The heat-stable enterotoxin (ST) was produced with a batch fermentor under agitation (500 rpm) and forced aeration (5 liters/min) in Casamino Acids yeast extract medium containing 0.2% glucose. The pH varied from 7.2 to 7.8. The maximum amount of ST was obtained after 7 h of growth. ST was purified by ammonium sulfate precipitation, ultrafiltration on Amicon membranes, and chromatography in Bio-Gel P-4. The enterotoxin, which was purified approximately 1,000 times, was active at nanogram levels. On 20% polyacrylamide gel electrophoresis, ST exhibited an Rf of 0.6 ST was recovered from the gel slices by eluting in buffer and testing the activity in suckling mice, since no band appeared on the gel after staining with Coomasie brilliant blue R, Schiff reagent, or red oil. ST was resistant at pH 2 to 10 and at 100 degrees C for 15 min, but it was inactivated at 121 degrees C; it did not lose biological activity after treatment with pronase, lipase, or amylase. In suckling mice antiserum obtained from rabbits or goats immunized with ST neutralized the enterotoxin activity of a cell-free supernatant of purified ST. 相似文献
783.
Benoit St-Pierre Melissa Cooper Zhe Jiang Eldad Zacksenhaus Sean E Egan 《Developmental dynamics》2004,230(1):124-130
Mammary gland development is a dynamic process involving cyclical proliferation, cellular differentiation, and cell death. In this study, we have determined that expression of the Stra13/Sharp/Dec basic helix-loop-helix (bHLH) family is dynamically regulated in mammary epithelium. In cultured HC11 cells, epidermal growth factor (EGF) treatment rapidly induces Stra13 protein accumulation, which is blocked by the synthetic glucocorticoid, dexamethasone. Neither the induction of Stra13 by EGF nor its repression by dexamethasone correlates with changes in Stra13 mRNA levels. During mouse mammary gland development in vivo, Stra13 is highly expressed in epithelial ducts during puberty, and strongly induced in both ducts and alveoli during early involution, while the related Sharp-1 gene is highly expressed only during late stages of involution. Together, these data indicate that Stra13/Dec/Sharp-family bHLH repressors are dynamically regulated during mammary gland development and may function to regulate apoptosis in this tissue. 相似文献
784.
Expression of embryonic zeta-globin and epsilon-globin chains in a 10- year-old girl with congenital anemia 总被引:1,自引:0,他引:1
A 10-year-old Danish girl with congenital anemia is described. At birth, she had severe anemia and erythroblastosis and was transfused a number of times during the first year. The need for transfusions has since declined steadily. Her reticulocyte counts varied between 2% and 15%, and her bone marrow aspirate showed some dyserythropoietic features. Her hemoglobin F level was consistently elevated, up to as much as 41%. Her erythrocytes had a normal level of I antigen but an undetectable level of i antigen. Moreover, embryonic zeta-globin and epsilon-globin chains were present in some of her circulating erythrocytes. These findings may represent the manifestations of a new variant of congenital anemia. 相似文献
785.
重点中学中学生6 307人的抑郁障碍现况调查 总被引:2,自引:0,他引:2
目的了解中学生抑郁障碍的患病情况.方法在北京、辽宁、安徽3省市各随机取1所重点中学,在同1个月内分别对该校全体非毕业班的在校中学生6 307人采用抑郁自评量表进行抑郁障碍的筛查.对筛查结果异常及由班主任提供的筛查结果虽正常但怀疑有情绪问题的学生进行精神科检查,根据ICD-10中F32抑郁发作、抑郁复发和F34.1恶劣心境的诊断标准筛选出抑郁障碍的学生.其中北京市某校参加学生(北京组)3 727人;辽宁省某校学生(辽宁组)1 637人;安徽省某校高一年级学生943人(安徽组).结果发放问卷6 307份,收回合格问卷6 307份,有效率100%.①在6 307人,抑郁自评量表筛查的阳性率为23.50%;诊断为抑郁障碍的学生184例,患病率2.92%(184/6 307).其中北京组89例,辽宁组45例,安徽组50例.男女学生抑郁障碍的发病情况接近,差异无显著性意义(85/3 016,99/3 291,x2=0.392,P=0.531).三所中学高一学生的总检出率以安徽最高(50/943),辽宁次之(32/870),北京最低(25/668),差异无显著性意义(x2=5.423,P=0.066).北京组高中学生抑郁障碍患病率与辽宁组接近,差异无显著性意义[3.11%(42/1349),2.75%(45/1647),x2=0.344,P=0.558].②北京组中学学生抑郁障碍的总患病率为2.39%.初一学生的总患病率明显低于初二、高一、高二学生,且差异有显著性意义(P=0.001,0.011,0.037).但各年级中学生抑郁障碍男女性别之间差异均无显著性.③辽宁组中学学生抑郁障碍总检出率为2.75%.高一学生抑郁障碍患病率明显高于高二学生(3.68%,1.84%,x2=6.016,P=0.0146);各年级男女学生抑郁障碍患病率差异无显著性.④安徽组高一学生抑郁障碍总患病率为5.31%(50/943),男女学生差异无显著性意义(5.20%,5.44%,x2=0.027,P=0.870).结论所调查的重点中学学生中抑郁障碍比较常见,从初二年级开始出现有较明显的增加趋势,男女学生抑郁障碍的患病情况无明显差别. 相似文献
786.
EL Blundell ; DH Pamphilon ; ID Fraser ; JE Menitove ; TJ Greenwalt ; EL Snyder ; AJ Repucci ; SL Hedberg ; JK Anderson ; DH Buchholz ; LR Kagen ; RH Aster 《Transfusion》1996,36(4):296-302
BACKGROUND: Irradiation of platelet concentrates (PCs) with ultraviolet- B (UVB) light inactivates the contaminating white cells and might be an alternative to filtration for the prevention of alloimmunization to HLA antigens and subsequent refractoriness to further platelet transfusions in multiply transfused patients with bone marrow failure. STUDY DESIGN AND METHODS: Patients with hematologic malignancy, mainly acute myeloid leukemia, were prospectively assigned in a random manner to receive either UVB-irradiated or control, nonirradiated PCs. All patients were given red cells that were white cell reduced by filtration. Transfusion efficacy and alloimmunization were assessed by means of corrected count increments, requirement for red cells and PCs, and measurement of lymphocyte-reactive antibodies. RESULTS: UVB-irradiated PCs had a clinical efficacy similar to controls as judged by corrected count increments at 1 to 6 and 12 to 24 hours and by the median requirement for red cell and platelet transfusions. Alloimmunization determined by measurements of lymphocyte-reactive antibodies using both conventional and antiglobulin-augmented lymphocytotoxicity techniques was not abolished in recipients of UVB-irradiated PCs (4/30, 13%) but was less than that in controls (5/20, 25%; p = NS). The mean number of platelet transfusion episodes prior to the occurrence of alloimmunization was greater in the control group (27 vs. 10; p = 0.017). CONCLUSION: In this trial, UVB irradiation did not diminish the clinical efficacy of platelet transfusions. There was a small but nonsignificant reduction alloimmunization, but no difference in refractoriness of the two groups was observed. Larger prospective randomized studies are required to confirm these findings and to compare UVB irradiation with white cell reduction. 相似文献
787.
788.
DH Buchholz ; JP AuBuchon ; EL Snyder ; R Kandler ; V Piscitelli ; C Pickard ; P Napychank ; S Edberg 《Transfusion》1994,34(10):852-857
BACKGROUND: While prestorage white cell (WBC) reduction by filtration may improve platelet and red cell quality, it also may remove an important anti-bacterial defense mechanism, especially if blood is WBC- reduced shortly after collection. STUDY DESIGN AND METHODS: The question of whether WBC reduction of platelet concentrates and red cells altered bacterial proliferation kinetics in components prepared from deliberately contaminated, freshly collected blood was investigated. Two-unit pools of whole blood were inoculated, at a concentration of approximately one colony-forming unit per mL, with one of 17 bacterial species reported to have caused septicemia in transfusion recipients. Each pool was divided after inoculation, and components were prepared from the 2 units after a 7-hour room- temperature holding period. One unit of each AS-1 red cell or platelet pair was WBC-reduced, and the pairs were then stored for 42 days at 4 degrees C (red cells) or for 10 days at 22 degrees C (platelets). Quantitative bacterial cultures were performed at periodic intervals. RESULTS: In red cells, clinically significant bacterial proliferation occurred in only one instance (Serratia marcescens), and growth was less rapid in the WBC-reduced unit than in the control. Three patterns of growth were seen in platelet concentrates. In four cases, there was rapid proliferation in both test and control units, while on 13 occasions there was minimal replication in either pair. On six occasions, substantial growth was noted in control units, while few or no bacteria could be found in the WBC-reduced units. There was no evidence in either red cells or platelets that bacteria proliferated more rapidly in units that had been WBC-reduced before storage than they did in units in which WBCs were retained. CONCLUSION: Rather than increasing the risk of bacterial proliferation through removal of active phagocytic cells, WBC reduction by filtration before blood storage may act to reduce the likelihood of significant bacterial proliferation, possibly by removal of microorganisms along with WBCs. 相似文献
789.
M Mimeault A Fournier Y Dumont S St-Pierre R Quirion 《The Journal of pharmacology and experimental therapeutics》1991,258(3):1084-1090
Recent data have suggested that N-truncated human calcitonin gene-related peptide (hCGRP) fragments such as hCGRP8-37 and hCGRP12-37 behave as competitive antagonists in certain bioassays. The present study was undertaken to determine which amino acid residues between positions 8 to 12 are directly involved in ensuring high affinity and antagonist properties at CGRP receptors. In brain, atrium and vas deferens membrane preparations, hCGRP8-37 and hCGRP9-37 demonstrated affinities similar to or much higher than that of the native peptide hCGRP alpha. Shorter fragments such as hCGRP 10-37 and hCGRP 11-37 possessed less than 20% of the affinity of hCGRP alpha in these various assays demonstrating the critical importance of the Thr residue in position 9 for maintenance of adequate receptor affinity. In the in vitro guinea pig left and right atria bioassays, both hCGRP8-37 and hCGRP9-37 behaved as potent and competitive antagonists (pA2:7.0-7.7) of positive chronotropic and inotropic effects induced by hCGRP alpha. hCGRP 10-37 and hCGRP 11-37 were at least 10 times less potent (pA2: 6.1-6.6). Interestingly, both hCGRP 8-37 and hCGRP9-37 were much less potent (pA2: 6.2-6.3) in blocking the effects of hCGRP alpha in the rat vas deferens whereas only slight inhibition was observed at 1.0 microM with hCGRP10-37 and no blocking activity was detected with hCGRP11-37 at a low micromolar concentration. These results are in accordance with binding data and demonstrate further the importance of residues in positions 9 (Thr) and 10 (His) to ensure potent antagonistic properties of N-truncated hCGRP fragments.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
790.