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排序方式: 共有722条查询结果,搜索用时 9 毫秒
1.
Yuji Masuda Toyonobu Yamashita Tetsuji Hirao Motoji Takahashi 《Skin research and technology》2009,15(2):224-229
Background/purpose: It is crucial to establish an accurate method for measuring skin pigmentation in cosmetic science and clinical dermatology. Here, we report a non-invasive precise method for measuring skin melanin content.
Methods: In order to determine the concentrations of melanin and hemoglobin in skin, we used the spectrum resolution (SR) method. In brief, the absorption spectrum of the skin was calculated from the reflection spectrum using a spectrophotometer. The concentrations of melanin and hemoglobin were then determined using a multiple regression analysis, assuming that the absorption spectrum of the skin is expressed as a linear summation of the absorptions of melanin and hemoglobin according to the Lambert–Beer law. The skin changes in the volar forearm, which had been irradiated by ultraviolet rays (UV), were observed daily by the SR method.
Results: A multiple regression analysis with an absorption spectrum of 500–700 nm was performed. The multiple correlation coefficient was 0.993, resulting in a satisfactory precise estimate of the concentrations of melanin. After UV irradiation, the concentration of melanin monitored by the SR method increased until 8 days and decreased gradually afterwards.
Conclusions: The SR method allows the evaluation of the changes of epidermal melanin induced by UV irradiation. 相似文献
Methods: In order to determine the concentrations of melanin and hemoglobin in skin, we used the spectrum resolution (SR) method. In brief, the absorption spectrum of the skin was calculated from the reflection spectrum using a spectrophotometer. The concentrations of melanin and hemoglobin were then determined using a multiple regression analysis, assuming that the absorption spectrum of the skin is expressed as a linear summation of the absorptions of melanin and hemoglobin according to the Lambert–Beer law. The skin changes in the volar forearm, which had been irradiated by ultraviolet rays (UV), were observed daily by the SR method.
Results: A multiple regression analysis with an absorption spectrum of 500–700 nm was performed. The multiple correlation coefficient was 0.993, resulting in a satisfactory precise estimate of the concentrations of melanin. After UV irradiation, the concentration of melanin monitored by the SR method increased until 8 days and decreased gradually afterwards.
Conclusions: The SR method allows the evaluation of the changes of epidermal melanin induced by UV irradiation. 相似文献
2.
本文对12例支气管哮喘病人作了22例次支气管肺泡灌洗,其中3例次为重度哮喘发作;8例次为中度发作[1];11例次为缓解期.灌洗方法在一般肺灌洗的基础上经过改良后,12例病人无1例死亡.11例次哮喘发作患者,灌洗后临床症状皆有不同程度改善.11例次缓解期病人,灌洗后皆无不良反应.凡哮喘时间较长者,均能灌洗出较大量脓痰栓. 相似文献
3.
目的 :观察骨延长术对血清微量元素的影响。方法 :采用实验家兔 6只 ,造成左胫骨中段骨延长模型 ,定期耳缘静脉采血。原子吸收分光光度仪测定血清中锌、铜、铁的含量。结果 :骨延长术后血清铜元素含量呈上升趋势 ,血清铁、锌元素含量明显下降。在延长结束后 5d时与术前比较有明显差别 (P <0 .0 5 )。结论 :骨延长术后 ,血清铁、锌元素含量呈阶段性下降 ,适时予以补充 ,有利于骨组织的修复。 相似文献
4.
Journal of Anesthesia - 相似文献
5.
纤维支气管镜检查确诊的气管、支气管结核41例分析 总被引:2,自引:0,他引:2
目的:通过分析纤维支气管镜下气管,支气管结核的表现,引起临床医生对此病的重视,提高诊断率,避免误诊和漏诊。方法:采用Olympus纤维支气管镜对气管,支气管进行常规检查,根据需要进行活检,刷检和灌洗。结果:41例中33例经活检,刷检和灌洗证实为结核,8例经抗结核治疗后病变吸收证实为结核。结论:纤维支气管镜检查及活检是目前诊断本病的重要方法。 相似文献
6.
《Auris, nasus, larynx》2022,49(6):986-994
ObjectiveDysphagia is a common symptom in Parkinson's disease (PD) and it represents a negative prognostic factor because of its complications. This study is to evaluate pharyngeal dysphagia for boluses of various consistencies with Fiberoptic Endoscopic Evaluation of Swallowing (FEES) and Pharyngeal High-Resolution Manometry (PHRM) in a group of PD patients, making a comparison between the information provided by the two exams.MethodsGroup of 20 patients affected by PD was selected and initially subjected to a qualitative evaluation of the swallowing performing FEES. Subsequently, they were evaluated by PHRM to identify quantitative measures associated with pressures expressed by pharyngeal organs during swallowing. Values obtained in the study group were compared with those recorded in a group of 20 healthy subjects.ResultsStudy showed that Pmax (the maximum pressure elicited by the single pharyngeal muscle structures involved in swallowing) was significantly lower than the control group (p<0.05) for all the boluses and consistency tested, in particular for the Tongue base and the Cricopharyngeal muscle. Pmean pre-swallowing pressure (represents the mean value of a contraction in which basal and maximal pressure where normally calculated) was significantly higher compared to normal subjects for the Tongue base and the Cricopharyngeal muscle (p<0.05). Mean intra-swallowing pressure was higher for the Velopharynx and the Cricopharyngeal muscle, but lower for the tongue base. Pmax and Pmean at PHRM were altered independently to the degree of dysphagia detected at FEES, and they did not correlate either with the location of the residue or with the type of bolus. Images displayed at the FEES, found the corresponding biomechanical explanations in the PHRM, which also allowed us to quantify the extent of the dysfunction, through the calculation of the pressures generated in the various structures studied.ConclusionPHRM is particularly useful in the early detection of dysphagia, when FEES may still show no evidence of abnormal swallowing. 相似文献
7.
8.
This study aimed to evaluate the color change of teeth bleached with light activation using two different objective color measurement approaches after two years of clinical follow-up. A cross-sectional retrospective clinical study according to STROBE was followed including 30 participants. The 25% hydrogen peroxide gel (Philips Zoom) was applied with a supplementary LED light for 15 min in four cycles. Tooth color was assessed based on CIEL*a*b* values using a spectrophotometer (Spectroshade) at different time points (baseline, post bleaching, 1 week, 1 year, and 2 years). Standardized digital photographs were taken at each time point. The L*, a*, and b* values were measured from the digital photographs using Adobe Photoshop software. The color difference (ΔE) was separately calculated using the L*, a*, and b* values obtained with spectrophotometric and photographic analyses at each evaluation time. Data were analyzed with non-parametric tests (p < 0.05). A color regression was detected by both measurement approaches after 1 and 2 years (p < 0.05). Greater ΔE values were acquired with the spectrophotometer compared to the digital photographic analysis (p < 0.05). Although a greater color change was observed with the spectrophotometer, both approaches were able to detect the color rebound using the 25% hydrogen peroxide light-activated in-office system. Digital photographic analysis might therefore be used to assess color change after bleaching. 相似文献
9.
目的制备炉甘石薄荷脑洗剂,建立其质量控制方法 ,并对其含量测定方法进行考察。方法以炉甘石为主药制备炉甘石薄荷脑洗剂;采用络合滴定法测定锌盐的含量,采用紫外分光光度法测定苯酚含量。结果该络合滴定法测定锌盐的含量方法稳定;测定苯酚选择波长269.5nm为测定波长,测得吸收度(A)为定量依据。结果平均回收率100.33%,RSD为0.63%。结论测定制剂中锌盐和苯酚的含量方法均简单、准确。 相似文献
10.
目的应用大鼠在体肠灌流模型对豆腐果苷吸收机制进行研究。方法该实验在建立豆腐果苷在Krebs-Ringer缓冲液中的检测方法,及应用752紫外分光光度计测定Krebs-Ringer缓冲液中酚红溶液浓度的基础上,应用大鼠肠灌流模型研究豆腐果苷的吸收情况。结果通过该模型对豆腐果苷在大鼠十二指肠上部至回肠下部肠段中2 h内吸收情况的研究发现,豆腐果苷吸收迅速,15~20 min吸收即可达到平台。结论该实验建立了大鼠小肠灌流模型,并且将该模型用于豆腐果苷吸收情况的初步研究,为揭示豆腐果苷体内处置情况奠定了基础。 相似文献