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991.
992.
993.
Phrabhakaran Nambiar Norliza Ibrahim Yeti Rosalina Muslim Tandjung P. Shanmuhasuntharam 《Oral Radiology》2008,24(1):10-15
Objectives We conducted a study to determine the numbers of susuks (charm needles) and their distribution in the craniofacial region of susuk wearers, and the sex, racial affiliation, and age of the wearers. In addition, we sought to determine whether the presence
of susuks posed any potential hazard to patients undergoing magnetic resonance imaging (MRI).
Methods We studied various radiographs of 33 susuk wearers (age range, 33–69 years) and investigated the most common sites of insertion in the craniofacial region. A susuk was also suspended inside a 1.5-T MRI machine to determined whether it was attracted by the machine’s magnet.
Results The largest number of susuks that we observed in the craniofacial region was 39 pins, and susuks were particularly numerous in Malay Muslim women. Other sites with susuks were the maxillofacial region (except the temporomandibular region) and the forehead. The susuks showed no ferromagnetic characteristics.
Conclusions As susuks are made from gold, they are generally biocompatible with human tissue and do not cause problems to their wearers. Gold and
the other minor metal constituents found in susuks have no ferromagnetic characteristics and therefore pose no hazard to patients undergoing MRI. 相似文献
994.
Taking advantage of two large, population-based, and longitudinal datasets collected after the 1999 floods in Mexico (n = 561) and the September 11, 2001 terrorist attacks in New York (n = 1267), we examined the notion that resilience may be best understood and measured as one member of a set of trajectories that may follow exposure to trauma or severe stress. We hypothesized that resistance, resilience, recovery, relapsing/remitting, delayed dysfunction, and chronic dysfunction trajectories were all possible in the aftermath of major disasters. Semi-parametric group-based modeling yielded the strongest evidence for resistance (no or mild and stable symptoms), resilience (initially moderate or severe symptoms followed by a sharp decrease), recovery (initially moderate or severe symptoms followed by a gradual decrease), and chronic dysfunction (moderate or severe and stable symptoms), as these trajectories were prevalent in both samples. Neither Mexico nor New York showed a relapsing/remitting trajectory, and only New York showed a delayed dysfunction trajectory. Understanding patterns of psychological distress over time may present opportunities for interventions that aim to increase resilience, and decrease more adverse trajectories, after mass traumatic events. 相似文献
995.
目的:观察阿托伐他汀对系膜增殖性肾炎(MsPGN)大鼠肾组织细胞外基质(ECM)和纤溶酶原激活剂抑制物-1(PAI-1)表达的影响,探讨其肾脏保护作用的机制。方法:采用抗胸腺细胞血清诱发的MsPGN大鼠模型,将SD大鼠随机分为正常对照组、肾炎模型组、小剂量阿托伐他汀治疗组(8mg·kg^-1·d^-1)和大剂量阿托伐他汀治疗组(16mg·kg^-1·d^-1)。治疗12d后。检测各组大鼠血总胆固醇(CHOL)、甘油三酯(TG)、血肌酐(Scr)和24h尿蛋白,以及肾组织Ⅳ型胶原(Col Ⅳ)、纤维结合蛋白(FN)和PAI-1的表达。结果:阿托伐他汀治疗组大鼠24h尿蛋白、肾组织Col Ⅳ、FN和PAI-1 mRNA的表达明显下降。肾组织病理改变明显改善,与模型组相比有统计学差异(P〈0.05),且呈剂量依赖关系。其中肾炎模型组尿蛋白(30.34±0.62)mg/d。阿托伐他汀小剂量治疗组(21.17±0.79)mg/d,大剂量治疗组(9.77±0.54)mg/d。同时,各组血脂水平无明显差异(P〉0.05)。结论:阿托伐他汀可显著改善MsPGN大鼠肾脏病变,抑制肾组织ECM成分和PAI-1的表达。 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.
外科手术对心肌缺血的血运重建是目前治疗心肌缺血性疾病的重要手段之一。术中准确判断心肌缺血范围及程度和严密监测心脏停跳后心肌细胞损伤是否加重,对于血运重建的准确性,更好地实施心肌保护及对手术疗效的评估和术后处理方案的拟定有着重要意义。因此,如何在术中判断心肌缺血的损伤程度和范围具有极为重要的实验研究意义与临床现实意义。光学相干层析成像作为一种新颖的成像技术,能对活体组织内部微小结构进行实时、在体、高分辨率断层成像。 相似文献
998.
Hongbo Zhai Emi Dika Marina Goldovsky Howard I. Maibach 《Skin research and technology》2007,13(2):207-210
BACKGROUND/PURPOSE: If the occlusion time of a closed chamber evaporimeter on the skin is too long, saturation might occur. We previously compared an open chamber and a closed chamber device on healthy volunteers. Comparable data on stripped skin with higher evaporation rates are not available. This study compares the sensitivity and correlation of open and closed chamber devices in a tape-stripping human model. The amount of tape removed SC was also quantified with a protein assay method. METHODS: Ten healthy volunteers (six male and four female; seven Caucasians and three Asian; mean age 38+/-16) were enrolled. In a randomized manner, one forearm was measured by an open chamber device and the opposite by a closed chamber device. After recording baseline measurements, 20 strippings were taken on each test site with tape disks. Transepidermal water loss (TEWL) was measured at the end of 10 and 20 tape strippings at each test site. Stratum corneum (SC) aggregates in the strips was assayed. RESULTS: The mean values obtained from two devices were similar after 10 trips and 20 strips. There was no statistically significant difference. The closed chamber device showed a slightly higher (but not significant) inter-individual coefficient of variation. SC aggregates in the strips were similar and without a statistically significant difference. CONCLUSION: The study suggests that both devices might yield similar TEWL values on stripped human skin in vivo. 相似文献
999.
BACKGROUND: A profile of Child Behavior Checklist(CBCL) T-scores>or=70 on the attention problems, aggression, and anxious/depressed subscales has been proposed to identify juvenile bipolar disorder(JBD). We tested this hypothesis in a population-based sample. METHODS: Data for this analysis come from a birth-records-based twin sample having semi-structured interview and CBCL data (N=1,346). We compared prevalence of DSM-IV psychiatric disorders and suicidal behaviors in CBCL-JBD and non-CBCL-JBD subjects. Twin modeling assessed genetic and environmental contributions to CBCL-JBD. Associations with DRD4 and DAT1 were examined using chi-square tests. RESULTS: The prevalence of CBCL-JBD was 2.5%. No subjects with CBCL-JBD met criteria for bipolar or other mood disorders. CBCL-JBD subjects had more oppositional defiant disorder (ODD), conduct disorder(CD), and attention deficit hyperactivity disorder(ADHD). The CBCL-JBD profile was uncommon in these disorders. CBCL-JBD subjects more frequently endorsed suicidal behaviors. The CBCL-JBD profile was heritable and associated with the number of DAT1 9-repeat 3' untranslated region alleles. CONCLUSIONS: The CBCL-JBD phenotype does not correspond with a semi-structured interview assessment of JBD. ADHD, CD, and ODD are common in children with CBCL-JBD but do not account for the profile. Increased suicidal behaviors indicate substantial impairment in CBCL-JBD subjects. 相似文献
1000.
大鼠抗GBM肾炎模型的建立及不同病期的生化指标和肾组织病理学观察 总被引:10,自引:4,他引:6
目的:为研究人类新月体抗肾炎的发病机制,建立大鼠抗肾小球基底膜(BGM)肾炎的动物模型,方法:提取S-D大鼠GBM抗原,将此抗原免疫新西兰白兔获得抗血清,再将此抗血清从尾静脉一次性注射给S-D大鼠。实验分2组:肾炎模型组及正常对照组。定期于第4天、第14天第第21天检测大鼠24h尿蛋白,血肌酐及血尿素的含量和肾组织病理学改变。结果:大鼠肾炎模型组:大鼠注射抗血清后于第4天出现大量蛋白尿,第14天血肌酐,血尿素显著升高,并持续上升,肾组织病理表现为肾小球内细胞数明显增加,大量新月体形成及蛋白管型,GBM呈不规则增厚,足突融合,内皮细胞脱落,坏死,免疫荧光检查见IgG、鼠IgG沿GBM线形分布,大鼠正常对照组以上指标均无明显改变。结论:通过动态观察大鼠抗GBM肾炎的病变变化,证实该模型病变与人类新月体性肾炎的病变较为一致,该模型可用于探讨人类新月体体肾炎的实验研究。 相似文献