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71.
目的:探讨Schick数字化成像系统的临床应用,评价Schick数字化成像系统的成像质量。方法:随机选取Schick数字化成像系统所拍X线根尖片和Kodak根尖胶片各200张,比较其曝光时间和X线垂直角度,对其成像质量进行分级评价。结果:Schick数字化成像系统所拍根尖片成像质量I级者为90%,比Kodak根尖胶片高25%;Schick数字化成像系统所拍根尖片成像质量Ⅲ级和Ⅳ级所占比例为5%,与Kodak根尖胶片无明显差别。结论:采用Schi。k数字化成像系统拍摄根尖片成像质量优良,能较好地满足临床应用要求。  相似文献   
72.
去势大鼠干眼症模型眼表损伤的研究   总被引:1,自引:0,他引:1  
建立去势大鼠干眼症模型并对其眼表损伤进行研究。60只Wistar大鼠随机分为6组,每组10只。A组为雌性对照组,B组为雌性假手术组,C组为雌性去势组,D组为雄性对照组,E组为雄性假手术组,F组为雄性去势组。A组与D组大鼠正常饲养,不作处理。C组大鼠去除卵巢,B组重复手术过程但不去除大鼠卵巢,F组大鼠去除双侧睾丸及附睾,E组大鼠重复手术过程但不去除睾丸及附睾。所有大鼠均与术前及术后2、4、6月进行泪液分泌量、角膜上皮荧光素染色和泪膜破裂时间检测。A、B、D、E组大鼠泪液分泌量、角膜上皮荧光素染色和泪膜破裂时间检测均差异不显著(P>0.05)。去势组大鼠(组C和组F)角膜荧光染色在术后2月起为阳性,并随时间增加而加重。去势6月后,去势组(组C和组F)的泪液分泌量、泪膜破裂时间与其他组相比差异极显著(P<0.01),并且C组与F组相比差异极显著(P<0.01)。大鼠去势后造成眼表损伤可能是干眼症原因之一。  相似文献   
73.
Digital display use has been accepted to be implicated as a contributing factor for dry eye disease (DED). Abnormal blinking during computer operation, including a reduced blink rate and an incomplete eyelid closure, increased palpebral fissure as consequence of high visualization angles, and meibomian gland dysfunction associated to long-term display use, are behind the increased prevalence of dry eye signs and symptoms found in digital display users. Previous research reveals significant reductions in tear volume and stability, alterations in tear film composition, including increased osmolarity, inflammatory cytokines, oxidative stress markers and reduced mucin secretion, eyelid abnormalities and ocular surface damage, encompassing corneal and conjunctival staining and bulbar redness, as a direct consequence of digital display use. In this regard, individual differences in the way that the various digital displays are typically set up and used may account for differences in their effects on induced dryness signs and symptoms. Furthermore, factors such as the use of contact lenses or inappropriate working environments, usually accompanying the use of displays, may significantly increase the prevalence and the severity of induced dry eye. Other factors, such as old age and female gender are also relevant in the appearance of associated alterations. Finally, clinicians should adopt a treatment strategy based on a multidirectional approach, with various treatments being applied in conjunction.  相似文献   
74.
目的:探讨翼状胬肉切除联合游离结膜瓣移植术治疗原发性翼状胬肉的疗效及对泪膜功能的影响。方法:选择2018-01/2019-10我院收治的120例126眼原发性翼状胬肉患者作为研究对象,按照随机数字表法分为2组,结膜移植组62例64眼行翼状胬肉切除联合游离结膜瓣移植术治疗,羊膜移植组58例62眼行翼状胬肉切除联合羊膜移植治疗。测定术前,术后3、6mo时泪液分泌长度(SⅠt)、泪膜破裂时间(BUT)、角膜荧光素染色(FL)评分、非侵入性首次泪膜破裂时间(NIBUT)、泪河高度(TMH)、结膜杯状细胞数量,采用眼表疾病指数(OSDI)评估患者生活质量,于术后6mo时评估治疗效果及复发情况。结果:结膜移植组及羊膜移植组患者角膜上皮平均修复时间、症状持续时间比较均无差异(P>0.05)。术后6mo结膜移植组患者BUT(11.11±2.77s vs 10.01±2.41s)、NIBUT(10.01±1.52s vs 9.52±0.98s)高于羊膜移植组(P<0.05),FL评分(0.44±0.10分vs 0.50±0.11分)低于羊膜移植组(P<0.05)。术后两组患者结膜杯状细胞数量均明显增加(P<0.05),术后3、6mo时结膜移植组患者结膜杯状细胞数量多于羊膜移植组(311.41±58.45/mm2vs 285.46±68.96/mm2,342.41±66.89/mm2vs 314.41±70.12/mm2,均P<0.05)。术后两组患者OSDI评分均显著降低(P<0.05),结膜移植组、羊膜移植组患者OSDI评分组间无差异(P>0.05)。两组患者总体疗效无差异(P>0.05);结膜移植组及羊膜移植组患者复发率分别为6.3%、6.5%,组间无差异(P>0.05)。结论:翼状胬肉切除联合自体结膜瓣移植在术后恢复及预防翼状胬肉复发方面与羊膜移植相当,对患者泪膜功能稳定性有更好的改善效果。  相似文献   
75.
蒋玲  李凤  杨欣  万鹏飞 《国际眼科杂志》2021,21(9):1612-1616

目的:分析角膜缘自体结膜移植和羊膜移植对行翼状胬肉手术患者视力、角膜散光(CAD)、泪膜功能的影响。

方法:前瞻性研究。选取2018-08/2020-03我院眼科收治的翼状胬肉手术患者96例96眼,依据随机数字表法将其分为观察组(48例48眼,行翼状胬肉切除联合角膜缘自体结膜移植治疗)、对照组(48例48眼,行翼状胬肉切除联合羊膜移植治疗),比较两组患者手术时间、角膜上皮愈合时间、结膜充血及水肿消退时间、术后裸眼视力(UCVA)、泪膜功能\〖泪膜破裂时间(BUT)、泪液分泌试验(SⅠt)\〗、CAD、眼表疾病指数(OSDI)、复发率、并发症发生率。

结果:观察组患者手术时间较对照组长,而角膜上皮愈合时间短于对照组(P<0.001),两组患者结膜充血及水肿消退时间比较无差异(P>0.05); 术后1、3、6mo两组患者UCVA、BUT、SⅠt均较术前改善(P<0.05),CAD、OSDI评分较术前降低(P<0.05),且观察组术后1mo BUT、SⅠt较对照组低,术后3、6mo BUT、SⅠt较对照组长,术后1、3、6mo OSDI评分低于对照组(P<0.05),两组患者术后UCVA和CAD比较无差异(P>0.05); 观察组术后6mo内复发率低于对照组(P<0.05),而两组术后6mo内并发症发生率无差异(P>0.05)。

结论:与羊膜移植相比,角膜缘自体结膜移植联合翼状胬肉切除术治疗翼状胬肉患者可明显缩短角膜上皮愈合时间,减少对泪膜功能的影响及复发率,且不影响视力与CAD,安全性可靠。  相似文献   

76.
AIM: To compare the non-invasive tear film break-up time (NIBUT), tear break up time (TBUT), basal tear secretion (BTS) and blink rate in four ethnic groups: Malay, Chinese, Indian and Nigerian. METHODS: Totally 120 healthy (61 males and 59 females) subjects (without dry eye symptoms and ocular surface disorder) with the age 20 to 39 years were recruited; 30 were Malays, 30 were Chinese, 31 were Indians and 29 were Nigerians. Based on McMonnies questionnaire and clinical examination, normal subjects were selected. NIBUT, TBUT, BTS were assessed in only one eye (right) of each subject and blink rate was also assessed. RESULTS: There was significant difference in the NIBUT, TBUT, BTS and blink rate among 4 different ethnic groups (P=0.018, 0.001, 0.011, and 0.004 respectively). No statistically significant difference of NIBUT, TBUT, BTS and blink rate was found between the genders among different ethnic groups. Indian had higher median for NIBUT (10±6s), TBUT (7±5s) and BTS (20±20 mm) than other races. Chinese had lower median for NIBUT (7.5±4s) and TBUT (4±2s) while Malay had for BTS (9.5±16 mm) among the groups. There was no significant correlation of blink rate with NIBUT (r=-0.119, P=0.195), TBUT (r=-0.086, P=0.352), and BTS (r=-0.123, P=0.180) respectively. CONCLUSION: The tear-film measurement values are variability in four ethnic groups.  相似文献   
77.
目的 用放射性免冲洗胶片测量调强放射治疗(IMRT)多叶光栅(MLC)叶片到位精确度验证方法研究,为IMRT质量控制提供参考依据。方法 选择湖北省7家三甲医院的7台不同型号医用直线加速器,放射治疗计划系统(TPS)计划5条宽度为0.6 cm条状的栅栏,每条状野之间的距离为3.0 cm。用EBT2免冲洗胶片测量5条状野位置、多叶光栅叶片位置偏差和实际宽度。结果 按国际原子能机构(IAEA)要求,胶片测量与TPS计划每条栅栏野多叶光栅条状位置结果应≤±0.5 mm。编号5和编号7的加速器MLC条状野位置偏差分别为0.7和-1.0 mm,不符合IAEA要求。按IAEA要求,胶片测量每对与每条所有多叶光栅叶片平均位置偏差应≤±0.5 mm。7台加速器MLC每对叶片位置偏差均在±0.5 mm内,符合IAEA要求;IAEA要求单对MLC叶片开野宽度与该机器5条条状野平均开野宽度的差值不超过±0.75 mm,7台加速器每对MLC开野宽度与平均值的差值范围为-0.6~0.5 mm,符合要求。所有叶片开野宽度标准偏差应≤0.3 mm,7台加速器标准偏差在0.1~0.2 mm范围内,符合要求。结论 用EBT2免冲洗胶片验证MLC位置精确度方法操作简单、检测精度高,是质量控制(QA)的重要手段之一,适合大范围核查使用。  相似文献   
78.
目的比较透明薄膜敷料与水胶体透明敷料预防神经外科中心静脉导管细菌定植和细菌感染的效果,为合理选择中心静脉导管固定敷料提供依据。方法按照随机数字表法将神经外科行中心静脉置管患者470例分为对照组(230例)和观察组(240例),中心静脉置管后对照组采用透明薄膜敷料固定导管,观察组采用水胶体透明敷料固定导管。比较两组导管病原菌定植、导管相关性感染和导管相关性血源性感染、皮肤病原菌定植情况。结果观察组导管病原菌定植、导管相关性感染、导管相关性血源性感染以及皮肤病原菌定植的发生率显著低于对照组,导管感染发生时间显著延长(均P0.05)。结论水胶体透明敷料可以有效预防神经外科患者中心静脉导管细菌定植和细菌感染,具有良好的皮肤安全性。  相似文献   
79.
The development of hydrogel films as wound healing dressings is of a great interest owing to their biological tissue-like nature. Polyvinyl alcohol/polyethylene glycol (PVA/PEG) hydrogels loaded with asiaticoside, a standardized rich fraction of Centella asiatica, were successfully developed using the freeze–thaw method. Response surface methodology with Box–Behnken experimental design was employed to optimize the hydrogels. The hydrogels were characterized and optimized by gel fraction, swelling behavior, water vapor transmission rate and mechanical strength. The formulation with 8% PVA, 5% PEG 400 and five consecutive freeze–thaw cycles was selected as the optimized formulation and was further characterized by its drug release, rheological study, morphology, cytotoxicity and microbial studies. The optimized formulation showed more than 90% drug release at 12?hours. The rheological properties exhibited that the formulation has viscoelastic behavior and remains stable upon storage. Cell culture studies confirmed the biocompatible nature of the optimized hydrogel formulation. In the microbial limit tests, the optimized hydrogel showed no microbial growth. The developed optimized PVA/PEG hydrogel using freeze–thaw method was swellable, elastic, safe, and it can be considered as a promising new wound dressing formulation.  相似文献   
80.
《The ocular surface》2020,18(1):170-177
PurposeTo assess the clinical efficacy of a novel MGO Manuka Honey microemulsion (MHME) eye cream for the management of blepharitis.MethodsFifty-three participants (32 females, 21 males; mean ± SD age, 60 ± 12 years) with clinical signs of blepharitis were enrolled in a prospective, investigator-masked, randomized, paired-eye trial. The MHME eye cream (Manuka Health New Zealand) was applied to the closed eyelids of one eye (randomized) overnight for 3 months. Visual acuity, ocular surface characteristics, symptoms and tear film parameters were assessed at baseline, day 30, and day 90. Eyelid swab microbiology cultures were evaluated at baseline and day 90.ResultsBaseline measurements did not differ between treated and control eyes (all p > 0.05). Significant reductions in SANDE and SPEED symptomology scores were detected in treated eyes on days 30 and 90 (all p < 0.05), while clinical improvements in non-invasive tear film breakup time, lipid layer thickness, and inferior lid wiper epitheliopathy were observed on day 90 (all p < 0.05). Following the 3-month treatment period, ocular Demodex, Corynebacterium macginleyi, Propionibacterium acnes, and Staphylococcus epidermidis load decreased significantly in treated eyes (all p ≤ 0.001). There were no changes in visual acuity during the 90-day period (all p > 0.05), and no major adverse events were reported.ConclusionTopical overnight application of the MHME eye cream effected significant improvements in ocular surface symptomology, tear film stability and lipid layer thickness, and reduced lid margin staining, ocular Demodex and bacterial load. The favourable clinical efficacy and tolerability profile suggests promise for the MHME eye cream as a treatment for blepharitis management.Trial registration numberACTRN12616000539437.  相似文献   
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