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991.
背景 眼眶爆裂性骨折引起明显的眼球形态和功能的异常.眼眶解剖结构复杂,故眼眶骨折修复手术中植入物的设计和制作具有一定的难度,而计算机辅助设计与制作(CADM)技术有望提供一种新的方法,但其临床应用价值有待评估.目的 研究CADM技术在眼眶爆裂性骨折治疗中的应用方法,评价其临床效果.方法 对河南省眼科研究所河南省立眼科医院2006年7月至2012年7月收治的眼眶爆裂性骨折患者74例74眼的手术过程和疗效进行回顾性分析,其中CADM手术者58例58眼,非CADM手术者16例16眼,2个组间患者基线特征,如年龄、性别和眼别均匹配.CADM手术组术眼采用CADM技术进行个体化三维立体植入物的设计和制作并进行眶骨骨折缺损处的填充,非CADM手术组术眼采用常规羟基磷灰石人工骨或多孔聚乙烯高分子合成材料(Medpor)填充法.所有术眼术前均行常规眼部检查以及CT检查,术后随访22~69个月,在随访期间内定期进行眼部临床观察和CT检查.观察指标包括最佳矫正视力、眼球突出度、眼球位置、眼球运动和复视改善情况以及并发症情况.结果 CADM手术组和非CADM手术组术眼术前最佳矫正视力分别为0.71±0.37和0.69±0.41,术后最佳矫正视力分别为0.74±0.38和0.72±0.41,组间差异无统计学意义(F分组=0.043,P=0.837),术眼手术前后视力的总体比较差异有统计学意义(F时间=13.576,P<0.01),其中2个组术眼术后视力均好于术前,差异均有统计学意义(均P<0.05).2个组间复视和眼球运动障碍治愈和好转的眼数分布差异均无统计学意义(Z=-0.298,P=0.766;Z=-0.548,P=0.584).CADM手术组和非CADM手术组术眼术前眼球眼球内陷度值分别为(3.93±0.99) mm和(3.88±0.97)mm,术后分别为(0.91±0.67)mm和(1.84±0.80)mm,组间总体比较差异无统计学意义(F分组=3.558,P=0.063),各组术眼术后眼球眼球内陷度值均明显低于术前,差异均有统计学意义(均P<0.05).CT影像显示,CADM手术组术眼植入物在位,与眶骨骨折缺损处贴合良好,患者眼球位置及外观均恢复正常.非CADM手术组术眼发生植入物翘起并损伤内直肌.随访期内CADM手术组未发现组织感染、排斥反应等不良反应.结论 CADM技术用于眼眶爆裂性骨折的治疗可重建三维立体骨性眼眶,并有效改善患眼位置、眼球运动功能和视觉功能,其疗效优于传统植入物填充术.  相似文献   
992.
背景 脉络膜新生血管(CNV)是多种眼部疾病致盲的原因之一,研究发现补体系统在CNV的发病机制中起重要作用.目的 构建针对补体因子B(CFB)的小干扰RNA(siRNA)重组质粒,体外观察其对人脐静脉内皮细胞ECV-304增生的影响.方法 根据人CFB的基因序列设计引物,经PCR扩增后与质粒pRNAT-U6.1连接,得到重组质粒pRNAT-U6.1/CFB siRNA,并进行测序鉴定和PCR鉴定.ECV-304细胞株进行常规培养,用电转染技术将重组质粒或空质粒分别转染人ECV-304细胞株,分为CFB-siRNA转染组和空质粒转染组,未转染的细胞为空白对照组.细胞转染后继续培养48 h,于倒置荧光显微镜下观察绿色荧光蛋白(GFP)的表达并计算转染效率;采用半定量逆转录PCR(RT-PCR)法测定各组细胞中CFB mRNA的相对表达量;用MTT法检测各组细胞转染24、48和72 h时细胞的增生值(A)并计算生长抑制率;利用流式细胞技术检测各组细胞的生长周期变化.结果 PCR扩增的目的片段序列与CFB基因序列完全相符,ECV-304细胞转染后,倒置荧光显微镜下可见CFB-siRNA转染组和空质粒转染组的细胞中GFP呈绿色荧光.半定量RT-PCR结果显示,CFB-siRNA转染组、空质粒转染组和空白对照组的CFB mRNA相对表达量分别为0.07±0.04、0.14±0.02和0.14 ±0.03,总体比较差异有统计学意义(F=233.05,P=0.00);其中CFB-siRNA转染组CFB mRNA相对表达量明显低于空质粒转染组和空白对照组,差异均有统计学意义(均P<0.05).MTT法检测结果显示,各组不同时间细胞增生抑制率总体比较差异有统计学意义(F分组=212.99,P=0.00);CFB-siRNA转染组细胞转染24、48、72 h后细胞增生的抑制率分别为(23.45±0.01)%、(33.48±0.02)%和(45.49±0.01)%,明显高于同时间点空质粒转染组和空白对照组,差异均有统计学意义(均P<0.05).流式细胞仪检测结果显示,CFB-siRNA转染组、空质粒转染组和空白对照组G1期的细胞数占总细胞数的(44.4±0.5)%、(25.8±0.4)%和(27.9±0.6)%,总体比较差异有统计学意义(F=58.98,P=0.00);CFB-siRNA转染组G1期和G2期细胞所占百分比显著高于空白对照组和空质粒转染组,差异均有统计学意义(均P<0.05).结论 重组质粒pRNAT-U6.1/CFB siRNA可通过将细胞阻滞在G1期而有效抑制人脐静脉内皮细胞的增生.  相似文献   
993.

Background:

Infection with Trichostrongylus spp. is common among human and herbivorous in most parts of Iran, especially in southern and northern areas. The aim of present study was to identify Trichostrongylus spp. among human population using excreted egg specimens, by the molecular method, in Mazandaran Province, northern Iran.

Methods:

Overall, 33 positive fecal specimens were randomly sampled and examined. PCR amplification of ITS2-rDNA region was performed on the isolated egg and then a restriction fragment length polymorphism (RFLP) profile was considered to discriminate of Trichostrongylus spp.

Results:

A total of 33 positive fecal specimens, 29(78.9%), 4(12.1%) were found T. colubriformis and T. axei respectively. Our data appear the molecular evidence of both human T. colubriformis and T. axei infections in North of Iran.

Conclusion:

T. colubriformis was the probable most common zoonotic species causing human trichostrongylosis infection in the area  相似文献   
994.

Background:

Visceral leishmaniasis (VL) as one of the most important human parasitic disease is endemic in some parts of Iran. Several cases of VL have been reported recently in the Ilam Province. The current study aimed to assess the present status of human VL in the region.

Methods:

A random cluster sampling method was used to collect 456 serums samples from the children up to 12 years of age and 10% of adults living in urban and rural areas of the province. All the collected serum samples were tested by direct agglutination test (DAT) to detect anti- Leishmania infantum antibodies.

Results:

Of the examined 456 serum samples with direct agglutination test (DAT), only 21 (0.43%) sera showed anti- Leishmania antibodies at titers 1:400 and higher. Distribution of anti- Leishmania antibodies titers were: 1:400(n=4), 1:800(n=11), 1:1600(n=3), 1:3200(n=1), and 1:6400(n=1). Individuals with titers ≥1:3200 showed clinical signs and symptoms such as fever and splenomegaly. The highest and lowest seropositivity were observed in the age groups of 5–9 and >15 years old, respectively. There were no significant difference between the rate of seropositivity in males and females.

Conclusion:

VL with a low prevalence circulates in some parts of Ilam province, particularly in the southern parts. Complementary studies should be needed to find animal reservoir hosts and vectors. Furthermore, health systems and physicians should pay particular attention to the disease.  相似文献   
995.
The human papillomavirus (HPV) vaccine has the potential to decrease the incidence of several cancers that affect women and men. Despite recommendations by the medical and public health community, and the incorporation of the vaccine into the adolescent immunization schedule, uptake of the vaccine remains well below target goals. To understand potential physician barriers to recommendation and provision of the vaccine, a cross-sectional survey was administered to Hawai‘i pediatricians and family physicians from July 2012 to September 2012 on their attitudes, practices, and perceived barriers regarding HPV vaccination. Surveys were mailed to 465 members of the local pediatrics and family medicine professional chapters, and 87 responses were received for a response rate of 19%. After excluding 14 responses, 73 surveys were included in the analysis. Although almost all of the respondents reported stocking and administering the HPV vaccine in their offices, only 71% reported strongly recommending the HPV vaccine to girls 11–12 years, and only 57% strongly recommend the vaccine to boys 11–12 years old. Lack of insurance coverage and other financial considerations were barriers to provision of the vaccine by physicians. Physicians who felt it is necessary to discuss sexuality with patients prior to recommending the vaccine were significantly less likely to strongly recommend the vaccine to boys 11–12 years old. Public health efforts should focus on addressing the financial barriers and encouraging physicians to recommend the HPV vaccine according to the guidelines.  相似文献   
996.
目的探讨呼吸道定植菌对人类偏肺病毒(hMPV)感染患儿喘息的影响。方法收集531例hMPV感染患儿鼻咽分泌物,RT-PCR检测hMPV,普通痰培养法检测细菌,观察肺炎链球菌(SP)、流感嗜血杆菌(HI)、卡他莫拉菌(MC)和金黄色葡萄球菌(SA)定植情况。分析四种定植菌与hMPV感染患儿临床表现的关系。结果 hMPV感染患儿中,SP、HI、MC和SA定植主要见于3岁以下患儿,无明显性别差异。定植菌阳性组喘息发生率高于定植菌阴性组(73.6%vs.49.1%)(P<0.05)。细菌(主要是SP、HI和MC)定植与hMPV感染患儿喘息症状相关(OR=3.27,P<0.01)。结论鼻咽部定植菌,尤其是SP、HI、MC,对hMPV感染患儿的喘息症状有重要影响。  相似文献   
997.
Many trace elements are considered essential [iron (Fe), zinc (Zn), copper (Cu)], whereas others may be harmful [lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As)], depending on their concentration and chemical form. In most cases, the diet is the main pathway by which they enter our organism. The presence of toxic trace elements in food has been known for a long time, and many of the food matrices that carry them have been identified. This has led to the appearance of legislation and recommendations concerning consumption. Given that the main route of exposure is oral, passage through the gastrointestinal tract plays a fundamental role in their entry into the organism, where they exert their toxic effect. Although the digestive system can be considered to be of crucial importance in their toxicity, in most cases we do not know the events that occur during the passage of these elements through the gastrointestinal tract and of ascertaining whether they may have some kind of toxic effect on it. The aim of this review is to summarize available information on this subject, concentrating on the toxic trace elements that are of greatest interest for organizations concerned with food safety and health: Pb, Cd, Hg and As.  相似文献   
998.
目的 了解无锡地区妇女宫颈人乳头瘤病毒(HPV)感染与宫颈病变的关系.方法 2013年参加无锡市免费宫颈癌筛查妇女157 240例,年龄35-64岁.检查项目:阴道分泌物检查和HPV检测,选择性宫颈液基薄层细胞学检查、阴道镜检查及组织病理学诊断.结果 宫颈病变总检出率52.40/万;农村妇女宫颈病变检出率高于城区(68.06/万vs.40.01/万)(P<0.01).各年龄组宫颈病变检出率:35-39岁为58.21/万;40-44岁为65.69/万;45-49岁为61.71/万;50-54岁为57.98/万;55-64岁为35.20/万.55-64岁妇女宫颈病变检出率低于其他年龄组(P<0.01).宫颈病变患者中,HPV高危阳性检出率98.91%;其中,HPV16检出率最高(48.54%),且随着宫颈病变程度加重而升高.单一感染率高于多重感染率(70.60%vs.29.40%)(P<0.05).结论 55-64岁妇女宫颈病变发生率明显低于35-54岁者.HPV16是高度宫颈病变的危险因素.  相似文献   
999.
Human parechovirus type 3 (HPeV3) is an emerging pathogen that causes sepsis and meningoencephalitis in young infants. To test the hypothesis that maternal antibodies can protect this population, we measured neutralizing antibody titers (NATs) to HPeV3 and other genotypes (HPeV1 and HPeV6) in 175 cord blood samples in Japan. The seropositivity rate (>1:32) for HPeV3 was 61%, similar to that for the other genotypes, but decreased significantly as maternal age increased (p<0.001). Furthermore, during the 2014 HPeV3 epidemic, prospective measurement of NATs to HPeV3 in 45 patients with severe diseases caused by HPeV3 infection showed low NATs (<1:16) at onset and persistently high NATs (>1:512) until age 6 months. All intravenous immunoglobulin samples tested elicited high NATs to HPeV3. Our findings indicate that maternal antibodies to HPeV3 may help protect young infants from severe diseases related to HPeV3 and that antibody supplementation may benefit these patients.  相似文献   
1000.
Phthalates are a class of chemicals widely used as plasticisers in a multitude of common consumer products. Through contact with such products, people are regularly exposed to phthalates, which are suspected to contribute to adverse health effects, particularly in the reproductive system.In the present study, 14 urinary phthalate metabolites of 10 parent phthalates were analysed by HPLC–MS/MS among the Austrian population aged 6–15 and 18–81 years in order to assess phthalate exposure. In the total study population, ranges of urinary phthalate metabolite concentrations were n.d.–2,105 μg/l (median 25 μg/l) for monoethyl phthalate (MEP), n.d.–88 μg/l (10 μg/l) for mono-n-butyl phthalate (MnBP), n.d.–248 μg/l (28 μg/l) for mono-isobutyl phthalate (MiBP), n.d.–57 μg/l (1.8 μg/l) for mono-benzyl phthalate (MBzP), n.d.–20 μg/l (n.d.) for mono-(2-ethylhexyl) phthalate (MEHP), n.d.–80 μg/l (2.6 μg/l) for mono-(2-ethyl-5-hydroxyhexyl) phthalate (5OH-MEHP), n.d.–57 μg/l (1.9 μg/l) for mono-(2-ethyl-5-oxohexyl) phthalate (5oxo-MEHP), n.d.–219 μg/l (11 μg/l) for mono-(5-carboxy-2-ethylpentyl) phthalate (5cx-MEPP), n.d.–188 μg/l (1.6 μg/l) for 3-carboxy-mono-proply phthalate (3cx-MPP), n.d.–5.5 μg/l (n.d.) for mono-cyclohexyl phthalate (MCHP), n.d.–4.5 μg/l (n.d.) for mono-n-pentyl phthalate (MnPeP), n.d.–3.4 μg/l (n.d.) for mono-n-octyl phthalate (MnOP), n.d.–13 μg/l (n.d.) for mono-isononyl phthalate (MiNP), and n.d.–1.1 μg/l (n.d.) for mono-isodecyl phthalate (MiDP). Generally, children exhibited higher levels of exposure to the majority of investigated phthalates, except to MEP, which was found in higher concentrations in adults and senior citizens at a maximum concentration of 2,105 μg/l. Individual daily intakes were estimated based on urinary creatinine and urinary volume excretion and were then compared to acceptable exposure levels, leading to the identification of exceedances of mainly the Tolerable Daily Intakes (TDI), especially among children. The execution of a cumulative risk assessment based on Hazard Indices showed cause for concern mainly for children, as well as in rare cases for adults.Although phthalate exposure seems to have decreased in previous years, the wide distribution and existing exceedances of acceptable levels indicate that phthalate exposure should be further monitored in order to identify exposure sources and enable appropriate minimisation measures.  相似文献   
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