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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.
目的评价肾移植术后普通环孢素A与环孢素A微乳剂对受者移植肾功能影响的差异。方法遵循Cochrane肾脏协作组随机对照试验检索策略,检索MEDLINE(1994—2006.3)、EMBASE(1994~2006.3)、中国生物医学文献数据库CBM(1994—2006.3)、Cochrane图书馆(2005年第4期)与肾移植相关的8种中文杂志。采用Revman4.2.7进行Meta分析。结果共有5个随机对照试验纳入研究,包括1671例同种异体尸体肾移植患者。结论肾移植术后使用普通环孢素A与环孢素A微乳剂相比受者移植肾功能无明显差异,但环孢素A微乳剂肾毒性发生率较高。 相似文献
995.
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
996.
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
997.
Tetsurou Torisu Kelun Wang Peter Svensson Antoon De Laat Hiroyuki Fujii Lars Arendt-Nielsen 《Clinical neurophysiology》2007,118(5):999-1009
OBJECTIVE: To investigate the effects of muscle fatigue induced by low-level isometric jaw-clenching and subsequent glutamate-evoked muscle pain on the exteroceptive suppression (ES) response and resting electromyographic (EMG) activities in human jaw muscles. METHODS: The resting EMG activity and the ESs were recorded before (baseline), after low-level jaw-clenching (Post1), after subsequent glutamate or isotonic saline injections into the left masseter (Post2), and 60 min after the clenching (Post3) in 23 healthy volunteers. RESULTS: The late ES (ES2) showed more inhibition at Post1 compared with baseline (P<0.05). It was less inhibited after both types of injections (Post2), and increased at Post3 again (P<0.05) with no significant difference between the glutamate and isotonic saline sessions. The resting EMG activity increased at Post1 and Post2 (P<0.05). The glutamate injection further increased the resting EMG activity in the injected muscle (P<0.01). CONCLUSIONS: Muscle fatigue influences inhibitory reflex pathways in jaw-closing muscles and subsequent acute muscle pain potentiates the local increase in the resting EMG activity of the painful muscle. SIGNIFICANCE: Muscle fatigue which can be observed in patients with oral dysfunctions may interact with nociceptive regulation and influence the clinical presentation of jaw symptoms and function. 相似文献
998.
999.
Transient Macular Edema after Laser In-Situ Keratomileusis 总被引:8,自引:0,他引:8
Bin Yang Zheng Wang Guofu Huang Xing Liu Yunlan Ling Xiaoping ZhengZhongshan Ophthalmic Center Sun Yat-sen University Guangzhou China 《眼科学报》2003,19(1):20-24
Purpose: To investigate the macular changes induced by laser in situ keratomileusisc(LASIK) procedure.Methods: Optical Coherence Tomography (OCT) was used to examine 27 eyes of 15LASIK patients before surgery, and 1 day, 1 week, 1 month after surgery.Results: The mean thick iness of neuroepithelial layer of macula was (195 ±24)microns, (178± 16) microns 1 day and 1 month after surgery, respectively, while thebaseline was (174 ± 12) microns. The increase in macular neuroepithelial thickness wascorrelated with the degree of myopia, but not with the duration of suction or thepostoperative BCVA.Conclusion: Mild macular edema is common in the first month following LASIK,especially in high myopia. However, no association with loss of BCVA has beenestablished. Eye Science 2003; 19: 20 - 24. 相似文献
1000.
普南扑灵滴眼剂在视网膜脱离手术中的应用 总被引:3,自引:1,他引:2
目的 探讨普南扑灵滴眼剂在减轻玻璃体视网膜术 (VRS)和巩膜扣带术 (SBS)后炎症反应的作用。方法 将 82例 (82只眼 )随机分为研究组和对照组 ,研究组 41例 (41只眼 ) ,选用 0 .1%普南扑灵滴眼剂点眼 ,对照组 41例 (41只眼 ) ,选用 0 .0 2 5 %地塞米松滴眼剂点眼。观察指标为眼部疼痛、充血、前房闪辉、角膜炎症、虹膜后粘连。结果 选用 0 .1%普南扑灵滴眼剂的研究组在缓解术后眼部疼痛方面及减轻玻璃体切割术后前房闪辉、虹膜后粘连方面优于对照组 ,差异有显著性 (P <0 .0 5~ 0 .0 1)。结论 普南扑灵能显著的减轻 VRS及 SBS后炎症反应。 相似文献