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1.
《Clinical neurophysiology》2021,132(12):3104-3115
ObjectiveWe aimed to establish an objective neurophysiological test protocol that can be used to assess the somatosensory nervous system.MethodsIn order to assess most fiber subtypes of the somatosensory nervous system, repetitive stimuli of seven different modalities (touch, vibration, pinprick, cold, contact heat, laser, and warmth) were synchronized with the electroencephalogram (EEG) and applied on the cheek and dorsum of the hand and dorsum of the foot in 21 healthy subjects and three polyneuropathy (PNP) patients. Latencies and amplitudes of the modalities were assessed and compared. Patients received quantitative sensory testing (QST) as reference.ResultsWe found reproducible evoked potentials recordings for touch, vibration, pinprick, contact-heat, and laser stimuli. The recording of warm-evoked potentials was challenging in young healthy subjects and not applicable in patients. Latencies were shortest within Aβ-fiber-mediated signals and longest within C-fibers. The test protocol detected function loss within the Aβ-fiber and Aδ-fiber-range in PNP patients. This function loss corresponded with QST findings.ConclusionIn this pilot study, we developed a neurophysiological test protocol that can specifically assess most of the somatosensory modalities. Despite technical challenges, initial patient data appear promising regarding a possible future clinical application.SignificanceEstablished and custom-made stimulators were combined to assess different fiber subtypes of the somatosensory nervous system using modality-specific evoked potentials.  相似文献   
2.
The use of endogenous Protoporphyrin IX generated through the heme biosynthetic pathway after administration of 5-aminolevulinic acid (ALA) has led to many applications in photodynamic therapy (PDT). In Buenos Aires, Argentina, the Centro de Investigaciones sobre Porfirinas y Porfirias (CIPYP), reported for the first time, in 1975, porphyrin synthesis from ALA in highly dividing plant tissues. Increased porphyrin synthesis in tumours as well as cell photosensitisation was reported soon after. Our group is also interested in studying the use of new synthetic lipophilic derivatives of ALA as well as ALA delivery in liposomes. We have elucidated the mechanism of ALA transport in mammalian and yeast cells. The interactions between ALA-PDT and nitric oxide were investigated in three murine adenocarcinoma cell lines. In the National University of Río Cuarto, Córdoba, a group is devoted to the synthesis of new porphyrin-derived photosensitisers to study their effects on photoinactivation of bacterial and mammalian cells death by PDT. At the Centre of Electron Microscopy of the Cordoba National University, a prototype of a 630 nm noncoherent light source was designed and constructed. Cost of the light source and scarce knowledge of the benefits of PDT by physicians limit the spread of the treatment throughout the country.  相似文献   
3.
AIM: The aim of this pilot study was an investigation on photodynamic therapy (PDT) whether it is a good alternative for treating periungual and subungual warts of the hands. STUDY DESIGN: Twenty patients (mean age: 30.5 years) with a total of 40 periungual and subungual warts were treated with PDT. A photosensitizer, 20%delta-aminolevulinic acid was applied on the warts. After a mean incubation time of 4.6 h (SD: 1.2), the warts were irradiated with the VersaLight for 5-30 min (15.2 +/- 4.3 min). RESULTS: After a mean of 4.5 treatments a mean clearance of 100% was achieved in 90% of the patients. One patient (5%) showed a clearance of 50% and another showed no improvement. The subungual or periungual location of the wart had no influence on the number of treatments or end result (P > 0.05). There were two recurrences during the mean follow-up period of 5.9 months (SD: 7.6). Besides mainly pain and hyperpigmentation, most treatments had no side-effects. CONCLUSION: PDT can offer a good alternative for treating periungual warts of the hands. Larger studies are indicated.  相似文献   
4.
为了研究亚麻子对鸡蛋黄以及鸡体内二十二碳六烯酸 (DHA)含量的影响 ,用添加亚麻子的饲料喂养蛋鸡(剂量组 ) 1 0周后 ,用气相色谱法检测鸡蛋黄和鸡体内DHA的含量。结果显示 ,与对照组相比 ,剂量组鸡蛋黄中α 亚麻酸 (ALA)和DHA的含量呈明显上升趋势 ,并发现剂量组蛋鸡的肝脏、脑中DHA含量也相应增加。提示亚麻子对于开发新型的保健食品具有一定价值  相似文献   
5.
目的 了解职业技术类院校护理及助产专业医学生的心理对其医患沟通技能的影响作用,为职业技术类院校的医学生医患沟通技能提升提供指导。 方法 利用成熟的医学生医患沟通态度、技能以及心理学相关量表设计调查问卷,采用全部抽样的方式,对忻州职业技术学院护理专业学生进行调研,并最终获得264份有效问卷用于逐步进入法的多元线性回归分析。 结果 分析结果表明,医学生学习医患沟通技能的积极态度(r=0.39,P<0.001)、情绪疏泄能力(r=0.29,P<0.001)、观点采择意识(r=0.20,P<0.001)对其医患沟通技能水平的作用具有统计学意义。 结论 职业技术类院校在培养医学生的医患沟通技能时,应重点关注学生的积极学习态度、情绪疏泄能力和观点采择意识。  相似文献   
6.
目的 通过已建立的小鼠睾丸体外培养系统,研究四种内分泌干扰物(Endocrine Disrupting Chemicals,EDCs)对男性内分泌系统的影响。 方法 将新生小鼠的睾丸组织在体外环境中培养24h,而后在培养基中分别加入浓度为0.1μM, 1μM, 10μM and 100μM的四种(DEHP、MEHP、NP、p, p’-DDE)内分泌干扰物并培养72h,同时设置对照组;培养结束后进行组织学观察,测定冻存培养基中睾酮和抑制素βB (INH-βB)的分泌水平,同时测定细胞色素P450侧链裂解酶(P450Scc)、3β-羟基类固醇脱氢酶(3β-HSD)、细胞色素P45017α-羟化酶(P450C17)和波形蛋白(vimentin)的基因表达情况。 结果 所有剂量组中睾酮的分泌水平均发生改变;P450Scc、3β-HSD、P450C17和INH-βB蛋白质的表达及mRNA水平均受到四种内分泌干扰物的影响(P<0.05);DEHP和MEHP降低了波形蛋白的mRNA水平(P<0.05),而NP和p, p’-DDE对波形蛋白没有显著影响(P>0.05)。 结论 本研究建立的体外培养新生小鼠睾丸模型中,所选的四种已知EDCs改变了两种睾丸激素水平,三种类固醇合成酶以及与支持细胞功能相关的波形蛋白的表达。  相似文献   
7.
目的 建立啤酒中4种N-亚硝胺类化合物(N-亚硝基二甲胺、N-亚硝基二乙胺、N-亚硝基二丙胺、N-亚硝基二苯胺)的同位素稀释固相萃取-气相色谱串联质谱测定方法。 方法 样品经活性炭固相萃取小柱富集、二氯甲烷洗脱,洗脱液经氮吹浓缩定容后,采用INNOWAX毛细管色谱柱分离,多反应监测(MRM)模式检测,同位素稀释内标法定量。 结果 各物质在5 μg/L~200 μg/L范围内线性关系良好,相关系数均大于0.9995。方法的检出限为0.03-0.10 μg/L,定量限为0.10~0.33 μg/L。不同水平的加标回收率为72.1%~100.3%,相对标准偏差为1.5%~9.5%(n=6)。 结论 该方法操作简单,灵敏度和准确度高,适用于啤酒中4种N-亚硝胺类化合物的测定。  相似文献   
8.
目的 了解云南省中-缅、中-老、中-越跨境婚姻家庭艾滋病、梅毒和乙肝检测情况,为完善跨境婚姻家庭预防母婴传播相关服务政策提供科学依据。 方法 对目前居住在云南省边境地区的中国籍和跨境婚姻家庭进行调查和访谈,收集一般人口学特征、最近一次怀孕期间三病检测情况等信息。经整理后,使用构成比和率对指标进行计算,使用卡方检验、秩和检验比较中国籍和跨境婚姻家庭各项检测服务状况。 结果 外籍媳妇主要以农民、文盲/小学、无经济收入的少数民族为主。配偶检测率,老挝籍低于当地中国籍媳妇(〖XC五号.EPS;P〗=7.87,P=0.005),缅甸籍、越南籍与当地中国籍没有差异;缅甸籍高于老挝籍和越南籍(〖XC五号.EPS;P〗=41.84,P<0.001)。三病检测点知晓率,缅甸籍媳妇低于当地中国籍媳妇(〖XC五号.EPS;P〗=6.11,P<0.03),越南籍、老挝籍与当地中国籍没有差异;老挝籍高于缅甸籍和越南籍(〖XC五号.EPS;P〗=44.03,P<0.001)。获得预防母婴传播相关知识比例,三个外籍媳妇均低于当地中国籍(〖XC五号.EPS;P〗=19.84,P<0.001;〖XC五号.EPS;P〗=7.52,P=0.006;〖XC五号.EPS;P〗=4.38,P=0.036)。 结论 边境地区针对跨境婚姻家庭开展艾滋病、梅毒和乙肝预防母婴传播相关工作取得实效,三病检测情况与当地中国籍基本一致,但在其他服务利用上仍存在一定差距,外籍媳妇孕早期三病检测率及其配偶检测率、相关预防母婴传播知识获取还有待提升,需要运用更加有效的服务管理模式来促进三病检测可及性的进一步提高。  相似文献   
9.
Lead was administred to adult female rats in drinking water (0;0.1:1 and 10 ppm) for 3 weeks before mating, during pregnancy and during 3 weeks after delivery. On day 21 after delivery the mothers and their newborns were sacrified and various parameters of blood -- lead concentration on (Pb-B), hematocrit (Htc), hemoglobin (Hb), free erythrocyte porphyrins (FEP), delta0aminolevulinate dehydratase (ALAD) -- and tissue -- ALAD, free tissue porphyrins (FTP), lead concentration (Pb-T) -- were determined. In mothers a significant increase in Pb-B and Pb concentration in kidney was found in the 10 ppm group, but this increase in lead concentration was not associated with any statistically significant modification of the biochemical parameters. In newborns, lead concentration in blood and in kidney was also significantly increased in the 10 ppm group and this lead exposure was associated with a decrease of the ALAD activity in blood and an increase of FTP in kidney. On the basis of the biochemical parameters investigated one can therefore conclude that the developing organism is more susceptible to the biological action of lead than the organism of adult animals and that the "no-effect" level of lead administered during pregnancy and in the neonatal period is around 1 ppm.  相似文献   
10.
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