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101.
Total radical trapping antioxidant potential (TRAP) and exercise 总被引:1,自引:0,他引:1
Sharpe PC; Duly EB; MacAuley D; McCrum EE; Mulholland C; Stott G; Boreham CA; Kennedy G; Evans AE; Trinick TR 《QJM : monthly journal of the Association of Physicians》1996,89(3):223-228
The relationship between physical activity, physical fitness and total
radical trapping antioxidant potential (TRAP) was examined in the Northern
Ireland Health and Activity Survey. This was a cross-sectional population
study (n = 1600) using a two-stage probability sample of the population.
TRAP was calculated using the sum of the individual serum antioxidant
concentrations (urate, protein thiols, ascorbate, alpha tocopherol and
bilirubin) multiplied by their respective stoichiometric values. Physical
fitness was determined by estimation of VO2max by extrapolation from
submaximal oxygen uptake, and physical activity was recorded by
computer-assisted interview. Mean serum TRAP concentrations were
significantly higher in males (653 +/- 8.2 mumol/l, mean +/- SEM) compared
to females (564 +/- 8.0 mumol/l) (p < 0.0001). Both male and female
smokers had significantly lower TRAP values than non-smokers (males p <
0.0001, females p = 0.02). In females, there was a positive relationship of
TRAP with age (p < 0.001) and body mass index (p < 0.001) but a
negative relationship with physical fitness (p < 0.05). The known
beneficial effects of exercise and activity do not appear to be directly
mediated through increased antioxidant status.
相似文献
102.
目的获得sHLA-G1重链分子及轻链β2微球蛋白(β2m)基因体外表达并纯化的相关蛋白质。方法RT-PCR扩增可溶性HLA-G1重链分子及人β2m轻链的cDNA序列,构建表达载体pET28a(+)/sHLA-G1及pET28a(+)/β2m,导入大肠杆菌BL21(DE3),IPTG诱导sHLA-G1及β2m蛋白表达,并以Ni-NTA亲和层析和CM-FF弱阳离子柱分别纯化,透析后浓缩保存。SDS-PAGE,Western-Blot鉴定目的蛋白的表达和纯化。结果成功克隆了sHLA-G1及2βm基因并构建了pET28a(+)-sHLA-G1、pET28a(+)-β2m原核高效表达载体;表达产物以可溶性形式存在,表达量>30%,纯化后产物纯度达到95%。结论成功表达并纯化出的sHLA-G1重链分子及轻链β2m有助于阐明可溶性HLA-G1的功能。 相似文献
103.
两种不同固位结构附着体义齿修复游离端缺失基牙及缺牙区牙槽嵴应力分布的比较 总被引:1,自引:0,他引:1
目的探讨不同固位结构的附着体义齿应力分布特点,为临床应用附着体义齿种类的选择提供依据。方法应用三维有限元的方法分别测定并比较应用键槽缓冲式附着体和柱状附着体修复下颌单侧游离端缺失基牙及牙槽嵴应力分布情况。结果键槽缓冲式附着体义齿对基牙产生应力值小于柱状附着体义齿,对缺牙区牙槽嵴应力大于柱状附着体义齿。结论键槽缓冲式附着体义齿较适合于基牙条件差的义齿修复,柱状附着体义齿较适合于缺牙区牙槽嵴条件差的义齿修复。 相似文献
104.
A. Figueiredo CA Fontes Ribeiro M. Gonçalo J. Almeida A. Poiares-Baptista and F. Teixeira 《Fundamental & clinical pharmacology》1990,4(2):147-158
The present study examined 15 patients previously resistant to conventional antihistamines, in which doxepin at doses in the range of 50-75 mg/day was shown to be effective in treatment of chronic urticaria and without significant adverse side effects. However, some controversy remains about its mechanism of action in this particular disease. The aim of the present study was to examine the muscarinic, H1 and H2 blocking activity of doxepin. The following methods were used: a) gastric acid hypersecretion induced by histamine and carbachol in the pylorus-ligated rat preparation; b) contractile dose-response curves to histamine and carbachol in the guinea pig ileum; c) dimaprit-stimulated guinea pig atrium in vitro. pA2 values were determined for atropine, mepyramine, cimetidine and doxepin. As regards histamine, doxepin (50 mg/kg, po) increased gastric pH and decreased secretion volume, gastric acid concentration and total acid output; with carbachol, doxepin weakly antagonized those values. In the ileum, doxepin competitively antagonized carbachol (pA2 = 7.08) and histamine (pA2 = 9.72); pA2 values for atropine and mepyramine against carbachol and histamine were 9.11 and 8.82, respectively. In the atria, the dose-response curve to dimaprit was also competitively displaced by cimetidine (pA2 = 6.69) and doxepin (pA2 = 6.00). Doxepin displayed a very high affinity for H1 histamine receptor, being 8-fold more potent than mepyramine. Doxepin showed significant H2 blocking activity which was 5 times less potent than that of cimetidine. Doxepin competitively antagonized carbachol in the guinea pig ileum, and was 107 times less potent than atropine. The combined H1, H2 and muscarinic blocking activities of doxepin may contribute towards explaining its clinical efficacy in the treatment of chronic urticaria. 相似文献
105.
The effectiveness of the confidential unit exclusion (CUE) procedure recommended by the Food and Drug Administration has been questioned by the blood banking community. The purpose of this study was to determine whether donors were informing the blood center correctly regarding the disposition (transfuse or do not transfuse) of their donated blood. A letter explaining the confidential study and requesting permission to send the participant a questionnaire noting his or her self-exclusion choice was mailed to 230 donors who had chosen transfuse and 276 donors who had chosen do not transfuse. After consent was obtained, participants were sent a second packet and asked to indicate whether they had chosen correctly and, if not, to identify reasons for that incorrect choice. A seven-word terminology quiz made up of words from the CUE form was also enclosed. All participants who had chosen transfuse indicated that this was the correct choice. Approximately 50 percent of those who had chosen do not transfuse indicated that this was an incorrect choice; the most common reason was that "I was not paying attention." The most frequently misunderstood term was "confidential." Donors who chose do not transfuse had a significantly higher rate of error on the terminology quiz (p less than 0.01) than did those who chose transfuse. 相似文献
106.
107.
Adaptive differentiation of murine lymphocytes. IV. (Responder × Nonresponder) F(1) T cells can be taught to preferentially help nonresponder,rather than responder, B cells 下载免费PDF全文
Responses to the synthetic terpolymer L-glutamic acid, L-lysine, L-tyrosine (GLT) in the mouse are controlled by H-2-1inked Ir-GLTgenes. (Responder × nonresponder) F(1) hybrid mice, themselves phenotypic responders, can be primed with GLT to develop specific helper cells capable of interacting with 2,4-dinitrophenyl hapten (DNP)-primed F(1) B cells in response to DNP-GLT. Unlike the indiscriminant ability of F(1) helper T cells for conventional antigens (i.e. not Ir gene-controlled), which can help B cells of either parental type (as well as F(1)) equally well, GLT-primed F(1) T cells can only provide help under normal circumstances for B lymphocytes of responder parent origin; they are unable to communicate effectively with nonresponder parental B cells (1, and the present studies). The present studies reveal, however, that the induction of a parental cell-induced allogeneic effect during priming of F(1) mice to GLT actually dictates the direction of cooperating preference that will be displayed by such F(1) helper cells for B cells of one parental type or the other. Thus, F(1) T cells, primed to GLT under the influence of an allogeneic effect induced by parental BALB/c cells, develop into effective helpers for nonresponder A/J B cells, but fail to develop effective helpers for responder BALB/c B cells, and vice-versa. In contrast, F(1) T cells, primed to GLT under the influence of an allogeneic effect induced by either parental type, display significantly enhanced levels of helper activity for B cells derived from F(1) donors. These results are interpreted to reflect the existence of two interdependent events provoked by the allogeneic effect: one event augments the differentiation of GLT-specific helper T cells belonging to the subset corresponding to the opposite parental type; this would explain the development of increased helper activity provided to partner B cells of opposite parental type (as well as of F(1) origin). The second event, we postulate, involves the production of responses against the receptors which normally self-recognize native cell interaction determinants; this form of anti-idiotype response is restricted against self- recognizing receptors of the same parental type used for induction of the allogeneic effect, hence explaining diminished helper activity of such F(1) cells for partner B lymphocytes of corresponding parental type. 相似文献
108.
Lima CA 《中国医药工业杂志》2009,40(4)
采用三种设计方案考察了白色念珠菌URM3622胞外分泌生产胶原酶的培养条件。首先进行26—2部分因子试验,结果表明转速和底物浓度对胶原酶的产量影响显著。根据以上结果,又设计了两次连续的23全因子分析,结果表明,在pH7.0、转速160r/min、底物浓度2%条件下培养白色念珠菌,发酵所得胶原酶活性最高。在pH8.2、45℃的环境中,胶原酶活性最大。所获胶原酶在pH7.2~8.2及28~45℃范围内稳定。 相似文献
109.
目的 探讨OSAHS患者血清炎症因子检测的临床意义.方法 OSAHS患者40例和正常对照30例,采用酶联免疫技术检测血清8-异前列烷(8-isoPG)、白三烯B4(LTB4)、TNF-α、IL-10水平,以全自动生化分析仪测定高敏C反应蛋白(Hs-CRP)的浓度,并与睡眠监测指标进行相关性分析.其中20例OSAHS患者分别经自动持续气道正压通气(Auto-CPAP)或悬雍垂软腭咽成形术(UPPP)治疗3个月后,复查睡眠呼吸监测和上述炎症因子.结果 ①OSAHS组睡眠后血清中8-isoPG、LTB4、TNF-α、IL-10和Hs-CRP分别为(36.59±14.89)ns/L、(14.75±6.25)μg/L、(1022.13±97.57)ns/L、(4.68±3.42)ng/L和(2.46±1.58)mg/L,正常对照组分别为(19.91±7.76)ng/L、(1.43±0.72)μg/L、(540.00±78.70)ng/L、(7.41±4.49)ng/L和(0.30±0.16)mg/L,两组比较差异均有统计学意义(P均<0.01).②OSAHS组血清中8-isoPG、LTB4、TNF-α 和Hs-CRP随病情严重度增高而升高,IL-10随病情严重度增高而降低(P均<0.05).③OSAHS患者睡眠后血清中8-isoPG、LTB4、TNF-α、Hs-CRP与呼吸暂停低通气指数(AHI)呈正相关(r值分别为0.863,0.746,0.868和0.842,P均<0.01);与睡眠中最低血氧饱和度(LspO2)呈负相关(r值分别为-0.623,-0.524,-0.618和-0.562,P均<0.01);与平均血氧饱和度(MSpO2)呈负相关(r值分别为-0.654,-0.573,-0.537和-0.589,P均<0.01);OSAHS患者睡眠后血清中IL-10与AHI呈负相关(r=-0.722,P<0.01),与睡眠中LSpO2呈正相关(r=0.564,P<0.01),与MSpO2呈正相关(r=0.505,P<0.01).@20例OSAHS患者经治疗3个月后血清8-isoPG、LTB4、TN-α及Hs-CRP均较治疗前下降,血清中IL-10比治疗前上升(P<0.01).⑤OSAHS患者治疗后血清8-isoPG、IL-10与正常对照组比较无显著差异(P0.05),血清LTB4、TNF-α和Hs-CRP比正常对照组水平高(P<0.01).结论 OSAHS患者存在夜间低氧后炎症反应及氧化应激增强,抗炎因子水平降低.炎症因子检测结合睡眠呼吸监测对判断OSAHS严重程度和治疗效果具有一定的临床意义. 相似文献
110.
N Mohebbi R Vargas‐Poussou SCA Hegemann B Schuknecht AD Kistler RP Wüthrich CA Wagner 《Clinical genetics》2013,83(3):274-278
Mohebbi N, Vargas‐Poussou R, Hegemann SCA, Schuknecht B, Kistler AD, Wüthrich RP, Wagner CA. Homozygous and compound heterozygous mutations in the ATP6V1B1 gene in patients with renal tubular acidosis and sensorineural hearing loss. Distal renal tubular acidosis (dRTA) is characterized by the inability to excrete acid in the renal collecting ducts resulting in inappropriately alkaline urine and hyperchloremic (normal anion gap) metabolic acidosis in the context of a normal (or near‐normal) glomerular filtration rate. Inborn dRTA can be due to autosomal dominant or recessive gene defects. Clinical symptoms vary from mild acidosis, incidental detection of kidney stones or renal tract calcification to severe findings such as failure to thrive, severe metabolic acidosis, and nephrocalcinosis. The majority of patients with recessive dRTA present with sensorineural hearing loss (SNHL). Few cases with abnormal widening of the vestibular aqueduct have been described with dRTA. Mutations in three different genes have been identified, namely SLC4A1, ATP6V1B1, and ATP6V0A4. Patients with mutations in the ATP6V1B1 proton pump subunit develop dRTA and in most of the cases sensorineural hearing loss early in childhood. We present two patients from two different and non‐consanguineous families with dRTA and SNHL. Direct sequencing of the ATP6V1B1 gene revealed that one patient harbors two homozygous mutations and the other one is a compound heterozygous. To our knowledge, this is the first case in the literature describing homozygosity in the same dRTA gene on both alleles. 相似文献