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991.
992.
Ofelia Dolores Hernández Ángel José Gutiérrez Dailos González‐Weller Gonzalo Lozano Enrique García Melón Carmen Rubio Arturo Hardisson 《Environmental toxicology》2010,25(3):227-233
This document shows the results obtained from a study on the concentration of toxic heavy metals in the internal tissue and exoskeleton of sea urchins, collected from their natural habitat. The levels of lead and cadmium were measured by Graphite Furnace Atomic Absorption Spectrometry. The mean concentrations of lead and cadmium in the internal tissue were 304.04 and 260.54 μg/kg respectively, whereas in the shell they were 185.02 and 142.48 μg/kg. We also performed a statistical analysis of the differences in the distribution of metals between their exoskeleton and their internal content, a correlation study of the metal content in internal tissue and shell and sampling areas, and a correlation study between the metal content and sample size. Since the sea urchin Diadema antillarum presents a wide range of variation in metal content, this study suggests that this species is an excellent bioindicator of heavy metal contamination. © 2009 Wiley Periodicals, Inc. Environ Toxicol, 2010. 相似文献
993.
Information literacy education for medical students in China 总被引:1,自引:0,他引:1
994.
目的 克隆表达结核分枝杆菌促Rv1009基因,序列测定正确后进行融合、表达.方法 采用热启动聚合酶链反应(Polymerase Chain Reaction,PCR)从结核分枝杆菌H37Rv基因组中扩增出Rv1009编码基因,用限制性内切酶消化后插入pGEX 4T-2载体中,将重组质粒转化大肠杆菌BL21(DE3),目的基因经IPTG诱导,表达Rv1009基因蛋白.结果 经PCR扩增在1300bp处发现一条目的片段,获得了结核分枝杆菌H37Rv株Rv1009基因蛋白,经诱导后高效表达分子量为64KD的外源蛋白,与预期分子量大小一致,凝胶自动扫描分析,在A600值为0.6,IPTG终浓度为0.3 mmol/L,诱导表达3 h时融合蛋白表达量即达峰值,占菌体总蛋白的22.8%.结论 构建了结核分枝杆菌Rv1009基因重组表达载体,获得了RPF样融合蛋白的高效表达,为今后深入研究奠定了基础. 相似文献
995.
目的探讨Ki-67和凋亡(Apoptosis)在肾盂输尿管癌中的表达及其与肿瘤细胞分级、病理分期及预后的关系。方法采用SABC法和TUNEL法对34例肾盂输尿管癌行Ki-67和凋亡检测。结果Ki-67和凋亡在肿瘤细胞分级间存在显著差异,Ki-67index:G2与G1比较P〈0.05,G3与G2比较P〈0.05,G3与G1比较P〈0.01;Apoptosis index:G2与G1比较P〈0.05,G3与G2比较P〈0.05,G3与G1比较P〈0.01。Ki-67和凋亡在肿瘤病理分期的T3与T1及T2与T1之间有显著差异,T2与T1比较P〈0.05,T3与T1比较P〈0.01,但T3与T2比较P〉0.05;Ki-67index以20%为界分为二组,Apoptosis index以3%为界分为二组,组间生存率有显著差异(P〈0.05)。Ki-67在肾盂输尿管癌中的表达与凋亡一致。结论肾盂输尿管癌细胞增殖与凋亡密切相关;凋亡可作为临床判断肾盂输尿管癌恶性程度、病理分期、细胞分级以及预后的一种客观量化指标。 相似文献
996.
计算机辅助精液分析男性不育患者精子运动参数与精子活力的相关性 总被引:2,自引:1,他引:1
目的探讨计算机辅助精液分析精子运动参数在评价男性不育患者精子活力中的价值。方法按《WHO人类精液及精子-宫颈黏液相互作用实验检验手册》标准,采用国产WLJY-9000伟力彩色精子质量检测系统对276例男性不育患者的精液进行平均直线运动速度、平均曲线运动速度、运动的前向性、运动的直线性、运动的摆动性、平均路径速度、精子活力及分级等进行检测并分析其相关性。结果276名男性不育患者的平均精子活力为(48.93±19.10)%,分级为A级(32.11±17.25)%、B级(17.03±8.91)%、C级(10.14±5.99)%。平均直线运动速度、平均曲线运动速度、运动的前向性、运动的直线性、运动的摆动性、平均路径速度与精子活力的相关系数分别为0.60(P〈0.01)、0.59(P〈0.01)、0.51(P〈0.01)、0.55(P〈0.01)、0.52(P〈0.01)、0.67(P〈0.01)。结论计算机辅助精液分析精子运动参数平均直线运动速度、平均曲线运动速度、平均路径速度是反映精子活力的有效指标,精子运动参数对男性不育的诊断和生育能力的评估具有实用意义。 相似文献
997.
目的:探讨直肠癌Miles术后内疝性肠梗阻的原因、预防和诊治.方法:对1998年1月至2006年10月间收治的直肠癌Miles术后并发内疝性肠梗阻5例进行回顾性分析.结果:Miles术后并发内疝性肠梗阻的发生率为6%(5/82),表现术后不同程度的腹胀,阵发性腹痛,呕吐,胃管引流液每天超过500 mL者,结肠造瘘口无排气排便;腹部轻压痛,肠鸣音活跃或亢进.腹部立、卧位X线片检查,均发现肠腔扩张、多个液平或孤立性肠袢扩张.5例均行剖腹探查而证实,疝内容物为回肠,其中行单纯粘连松解复位2例,部分回肠切除、端端吻合术3例.再次手术后均痊愈出院.结论:Miles术后内疝性肠梗阻常缺乏典型的临床表现,早期诊断和及时剖腹探查是处理的关键,其重点在于预防. 相似文献
998.
Z. Peng Q. Liu Q. Wang E. Rector Y. Ma R. Warrington 《Clinical and experimental allergy》2007,37(7):1040-1048
BACKGROUND: Immunotherapy with anti-IgE antibodies for treatment of allergy is promising but a short half-life and extremely high cost limit its application. OBJECTIVE: We sought to develop IgE vaccines that induce longer-lasting auto-antibodies to neutralize self-IgE as an alternative therapy. METHODS: The vaccine was made by conjugating three synthetic peptides corresponding to human IgE receptor-binding sites to a carrier, hepatitis B surface antigen. To test the immunogenicity of the vaccine, rats were immunized with the vaccine or hepatitis B surface antigen as control. Serum IgG titres to human IgE and the IgE of other species were measured. The inhibition by rat antisera of the binding of human IgE to its receptor was assessed by ELISA, flow cytometry analysis, and passive cutaneous anaphylaxis (PCA), and its ability to recognize receptor-bound IgE was examined. The in vivo effect of the vaccine was evaluated in trichosanthin-sensitized mice and rats. In the preventative study, vaccination started before sensitization commenced, while in the treatment study, vaccination started after sensitization. Sensitized mice and rats receiving injections of the carrier served as controls. Trichosanthin-specific IgE was measured using PCA. RESULTS: Sera from vaccine-immunized rats contained high titre antibodies that reacted with soluble and plate-bound but not with receptor-bound human IgE; they also reacted with mouse, rat, and dog IgE. Furthermore, the sera inhibited the binding of human IgE to its receptor in a dose-dependent manner. In preventative and treatment studies, serum trichosanthin-specific IgE levels were significantly reduced in vaccinated groups compared with controls. CONCLUSION: Antibodies against self-IgE can be induced by IgE peptide-based vaccines, which are effective in preventing the increase of IgE and in down-regulating IgE in sensitized animals. 相似文献
999.
目的:了解主动要求立体定向脑深部核团毁损术治疗药物依赖的群体术前心理症状的特征。方法:选择2004-07/11自愿在沈阳军区总医院神经外科手术治疗的阿片类药物依赖连续病例34例。采用90项症状自评量表独立测试评估心理健康状况,计算机获得结果。与国内常模和国内燕殿学组、朱军红组、万萍组所测结果进行统计学分析。结果以“均值±标准差”表示,应用SPSS软件对测量结果进行t检验。结果:34例患者均完成量表测试,全部进入结果分析。①主动要求手术治疗的患者,多为32岁左右的男性已婚的个体经营者患者。依赖物质以海洛因为主;首吸年龄小;持续时间长;滥用方式多;复吸率高,并以心理依赖为主。②症状自评量表测查,总分中最高分374分、160分以上者23例占67.6%,平均分高于国内常模,差异有显著性[(38.29±4.08),(24.92±18.4),P<0.001]。阳性项目数最高分86分、43分以上者24例占70.6%,平均分高于国内常模,差异有显著性。③心理障碍总患病率高达91.2%。心理障碍因子分超出常模的构成比从高到低分别为:抑郁和躯体化、焦虑、强迫、敌对、精神病性和其他、偏执、恐怖以及人际关系。心理障碍显现强度的排列为,抑郁、敌对、强迫和其他、躯体化、焦虑、人际关系、偏执、精神病性以及恐怖。④与国内燕殿学组比较差异无显著性;与朱军红组比较,仅强迫因子差异有显著性;与万萍组所测结果比较,躯体、抑郁、焦虑、敌对、恐怖和精神病症状因子差异均有显著性。结论:阿片类药物依赖的患者术前心理障碍是普遍存在的临床问题。了解患者术前心理症状的特征,便于围手术期医学干预方法的选择。有利于对术后疗效做出科学的评价。 相似文献
1000.
Katherine P Rankin Anli A Liu Sara Howard Hilary Slama Craig E Hou Karen Shuster Bruce L Miller 《Cognitive and behavioral neurology》2007,20(1):48-61
OBJECTIVE: To characterize dementia-induced changes in visual art production. BACKGROUND: Although case studies show altered visual artistic production in some patients with neurodegenerative disease, no case-controlled studies have quantified this phenomenon across groups of patients. METHOD: Forty-nine subjects [18 Alzheimer disease, 9 frontotemporal dementia (FTD), 9 semantic dementia (SD), 15 healthy older controls (NC)] underwent formal neuropsychologic testing of visuospatial, perceptual, and creative functioning, and produced 4 drawings. Subjective elements of drawings were rated by an expert panel that was blind to diagnosis. RESULTS: Despite equal performance on standard visuospatial tests, dementia groups produced distinct patterns of artistic features that were significantly different from NCs. FTDs used more disordered composition and less active mark-making (P<0.05). Both FTDs and SDs drawings were rated as more bizarre and demonstrated more facial distortion than NCs (P<0.05). Also, SDs drastically failed a standardized test of divergent creativity. Alzheimer disease artwork was more similar to controls than to FTDs or SDs, but showed a more muted color palette (P<0.05) and trends toward including fewer details, less ordered compositions, and occasional facial distortion. CONCLUSIONS: These group differences in artistic style likely resulted from disease-specific focal neurodegeneration, and elucidate the contributions of particular brain regions to the production of visual art. 相似文献