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81.
A 50-year-old Iranian diabetic woman with night blindness was referred to our clinic. Complete ophthalmic examination including ophthalmoscopy after dark adaptation and paraclinic evaluations such as fluorescein angiography and electroretinography were performed. Retinal neovascularization and preretinal haemorrhages compatible with high-risk characteristic proliferative diabetic retinopathy were observed bilaterally. In addition, a golden-yellowish discoloration of posterior pole was noted in her both eyes. The diagnosis of Oguchi's disease was made when this discoloration disappeared after dark adaptation for 3 h. Electroretinograms also confirmed the diagnosis by showing a slow negative wave followed by a slow positive wave in the photopic condition and absent a- and b-waves in the scotopic state. We concluded that proliferative diabetic retinopathy might occur in a patient with Oguchi's disease. This report represents this association in an Iranian patient for the first time.  相似文献   
82.
Impact of dry eye syndrome on vision-related quality of life   总被引:4,自引:0,他引:4  
PURPOSE: To evaluate the impact of dry eye syndrome (DES) on vision-associated quality of life. DESIGN: Cross-sectional study. METHODS: We identified 450 participants in the Women's Health Study (WHS) and 240 participants in the Physicians' Health Study (PHS) and sent a supplementary questionnaire asking how much their everyday activities were limited by symptoms of dry eye and to what degree problems with their eyes limited them in reading, driving, working at the computer, their professional activity, and watching television. By design, one-third of study subjects had clinically diagnosed DES or severe symptoms and two-thirds did not. We used logistic regression to examine relationships of DES with reported problems with everyday activities in each cohort and pooled estimates using meta-analysis methods. RESULTS: Of the participants invited, 85% completed the supplementary questionnaire, including 135 WHS and 55 PHS participants with DES, and 250 WHS and 149 PHS participants without DES. Controlling for age, diabetes, hypertension, and other factors, those with DES were more likely to report problems with reading ([odds ratio] OR = 3.64, 95% [confidence interval] CI 2.45 to 5.40, P < .0001); carrying out professional work (OR = 3.49, 95% CI 1.72 to 7.09, P= 0.001); using a computer (OR = 3.37, 95% CI 2.11 to 5.38, P < .0001); watching television (OR = 2.84, 95% CI 1.05 to 7.74, P = .04); driving during the day (OR = 2.80, 95% CI 1.58 to 4.96, P < .0001); and driving at night (OR = 2.20, 95% CI 1.48 to 3.28, P < .0001). CONCLUSIONS: DES is associated with a measurable adverse impact on several common and important tasks of daily living, further implicating this condition as an important public health problem deserving increased attention and resources.  相似文献   
83.

目的:分析白内障手术候选人的眼部生物特征参数。

方法:横断面研究。纳入2017-01/2021-09就诊于伊朗德黑兰Farabi眼科医院的4 607例白内障患者(4 607眼)。使用IOLMaster 700 评估眼轴(AL)、角膜曲率(Kf、Ks、Km)、前房深度(ACD)。根据AL分为22 mm25 mm组,根据ACD分为3.00 mm3.60 mm组。

结果:患者平均年龄60.3±14.1(8-95)岁,女2 243例(48.69%),男2 364例(51.31%)。AL、ACD 和平均角膜曲率范围分别为23.1-23.4 mm、3.1-3.2 mm和44.50-45.00 D。AL>25 mm组ACD平均值显著高于22 mm≤AL≤25 mm组和22 mmP<0.001)。ACD>3.60 mm组的平均AL显著高于3.00 mmP<0.001)。3.00 mm25 mm组的Kf、Ks、Km均值显著高于ACD>3.60 mm组和22 mmP<0.001)。

结论:AL长的白内障患者ACD更深,角膜更平坦; AL短的患者ACD较浅,角膜较陡。此外,深ACD患者的AL较长,角膜较平坦,浅ACD患者的AL较低,角膜较陡。  相似文献   

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87.
Curve of left ventricular (LV) volume changes throughout the cardiac cycle is a fundamental parameter for clinical evaluation of various cardiovascular diseases. Currently, this evaluation is often performed manually which is tedious and time consuming and suffers from significant interobserver and intraobserver variability. This paper introduces a new automatic method, based on nonlinear dimensionality reduction (NLDR) for extracting the curve of the LV volume changes over a cardiac cycle from two-dimensional (2-D) echocardiography images. Isometric feature mapping (Isomap) is one of the most popular NLDR algorithms. In this study, a modified version of Isomap algorithm, where image to image distance metric is computed using nonrigid registration, is applied on 2-D echocardiography images of one cycle of heart. Using this approach, the nonlinear information of these images is embedded in a 2-D manifold and each image is characterized by a symbol on the constructed manifold. This new representation visualizes the relationship between these images based on LV volume changes and allows extracting the curve of the LV volume changes automatically. Our method in comparison to the traditional segmentation algorithms does not need any LV myocardial segmentation and tracking, particularly difficult in the echocardiography images. Moreover, a large data set under various diseases for training is not required. The results obtained by our method are quantitatively evaluated to those obtained manually by the highly experienced echocardiographer on ten healthy volunteers and six patients which depict the usefulness of the presented method.  相似文献   
88.
Renal cell carcinoma (RCC) is the most common renal malignancy in adults and exhibits highly intrinsic and acquired resistance to standard therapeutic strategies. We sought to determine the anti-cancer activity of hydroalcoholic extract of Nigella sativa seeds (NSE) and thymoquinone (TQ). Human renal cell carcinoma (ACHN) and fibroblast L929 cell lines were treated with NSE and TQ, and cytotoxicity was measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium (MTT) assay. Cell death pattern was determined by annexin V and propidium iodine (PI)-staining methods. Exposure to NSE, TQ and cisplatin significantly inhibited the growth of ACHN cells and showed significant increase of early apoptotic cells. Normal cells were more resistant to NSE and TQ-induced effects. The present study demonstrates that N. sativa and TQ exert anti-proliferative and pro-apoptotic effects on ACHN cells in a concentration and time-dependent manner, which suggests their potential to be used as a new therapeutic strategy for renal cancers.  相似文献   
89.
Teenage pregnancy has been associated with adverse effects for the mother and the newborn (NB). In order to compare body composition (BC) between adolescents (Ad) and mature women (MW) during pregnancy and to determine the difference in birthweight and perinatal morbidity, pregnant Ad (n = 40) and MW (n = 227) were studied. BC changes between the second and third trimesters were determined by multifrequency bioelectrical impedance analysis, and birthweight and NB morbidity were evaluated. During the second and third trimesters of the pregnancy, fat mass was lower in the Ad group [16 kg (13–19)] than in the MW group [22 kg (17–27)] (P < 0.01; median and quartiles 1–3). Fat‐free mass increased by 3.09 kg (2.29–4.20) and 2.20 kg (1.0–3.59) (P ≤ 0.01), and total body water increased by 2.77 L (0.84–4.49) vs. 2.04 L (0.55–3.89) (P = 0.36), in the Ad and MW groups, respectively (median and quartiles 1–3). Birthweight was not significantly different between NBs of Ad (3223 ± 399 g) and NBs of MW (3312 ± 427 g, P = 0.22). The youngest Ad (<18 year old, n = 8) had NB with lower birthweight than MW (3031 ± 503 g, P = 0.06). NBs of Ad mothers showed a non‐significant trend towards a higher rate of morbidity relative to the NBs of MW. In conclusion, the BC of Ad differs from that of MW during pregnancy. In addition, the NB infants of Ad mothers tended to have a lower birthweight than those from MW, a result that suggests that the Ad should be in strict prenatal control.  相似文献   
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