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ABSTRACT

Various machine learning techniques have been developed for keratoconus detection and refractive surgery screening. These techniques utilize inputs from a range of corneal imaging devices and are built with automated decision trees, support vector machines, and various types of neural networks. In general, these techniques demonstrate very good differentiation of normal and keratoconic eyes, as well as good differentiation of normal and form fruste keratoconus. However, it is difficult to directly compare these studies, as keratoconus represents a wide spectrum of disease. More importantly, no public dataset exists for research purposes. Despite these challenges, machine learning in keratoconus detection and refractive surgery screening is a burgeoning field of study, with significant potential for continued advancement as imaging devices and techniques become more sophisticated.  相似文献   
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Purpose

The objectives of the study were to identify the incidence and pattern of dry eye after phacoemulsification and manual small incision cataract surgeries.

Methods

The study consisted of two groups of patients - Group 1 underwent manual small incision cataract surgery (SICS) and Group 2 underwent phacoemulsification. The dry eye-related data was collected preoperatively and at 1?week, 1?month and 3?months postoperatively. Ocular Surface Disease Index questionnaire, tear break-up time (TBUT) and Schirmer test – 1 were used to record the type of dry eye.

Results

One hundred eyes of 96 patients, including 35 (36.5%) men and 61 (63.5%) women with the mean age of 63.1 (±8.3) years were studied. Dry eyes were found in 42% eyes (p?<?0.001) of patients at 1?week follow-up. Fifteen percent and 9% of the eyes were dry at 1?month and 3?months after surgery, respectively. There were 34 (53.1%) and 8 (22.2%) dry eyes in SICS and phacoemulsification groups, respectively at one week postoperative follow-up which was a statistically significant difference.Majority of eyes (27/42, 64.3%) had mild dryness. There were significant differences in TBUT at 1?week, 1?month and 3?months postoperatively. At 1?week review, the SICS group had mean TUBT of 10.0 (±0.55) sec as compared to 13.9 (±0.70) sec in phacoemulsification group (p?<?0.001).

Conclusion

Incidence of dry eye is higher in SICS than phacoemulsification due to tear film instability. The clinicians should be conscious about dry eye symptoms and signs in an otherwise healthy eye after cataract surgery.  相似文献   
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Arsenic (As) and cadmium (Cd) have recently emerged as major health concerns owing to their strong association with diabetes mellitus (DM). We aimed to investigate the heavy metals exposure towards incidence of DM at various enzymatic and hormonal levels. Additionally, association of As and Cd with Zinc (Zn, essential metal) was also evaluated. Spot urine samples were collected to assess As, Cd and Zn through ICP-OES. Serum was analyzed by assay method for fasting blood glucose, liver and renal function biomarkers. ELISA was performed to investigate the impact of heavy metals on HbA1c, α-amylase, DPP-IV, IGF-1, leptin, GSH, MDA, SOD, HDL, FFA, TG and interleukin (IL)-6. Association of heavy metals with DM was measured by odds ratio (OR) and level of significance was assessed by Chi-squared test. Unpaired student's t-test was used to compare DM-associated risk factors in heavy metals-exposed and unexposed participants. As and Cd were detectable in 75.4% and 83% participants with mean concentration of 75.5 ppb and 54.5 ppb, respectively. For As exposure, OR in the third quartile was maximum ie 1.34 (95% CI, 0.80 to 2.23), however the result was not statistically significant (P > .05). For Cd exposure, OR in the fourth quartile was considerably high, 1.62 (95% CI, 1.00 to 2.61), with a significant probability value (P < .05). Urinary Cd was negatively associated with Zn. As and Cd exposure increases the incidence of DM in the general population. Impaired hormonal and enzymatic levels in diabetic and non-diabetic exposed participants reflect the multiple organ damage by heavy metal exposure.  相似文献   
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The present investigation was aimed at studying the possible role of curcumin against N-nitrosodiethylamine (NDEA)-induced toxicity in albino rats. Administration of NDEA to rats at a concentration of 0.1 mg/ml in drinking water ad libitum for 21 days produced toxicity in them, which was evident from histopathological changes in the rat livers, and increased levels of blood serum enzyme markers, i.e. aspartate transaminase, alanine transaminase, alkaline phosphatase, and lactate dehydrogenase. In addition, the levels of oxidative stress markers like lipid peroxidation (LPO), protein carbonyl (PCC), and glutathione-S-transferase (GST) activity were elevated and the total glutathione (GSH) content was reduced in the livers. The administration of curcumin to rats at concentrations of 10, 20, and 40 mg/ml in drinking water along with 0.1 mg/ml of NDEA for 21 days effectively suppressed NDEA-induced toxicity and also resulted in a dose-dependent reduction in the levels of blood serum enzyme markers (AST, ALT, ALP, and LDH). Moreover, LPO, PCC, and GST activity were reduced and the GSH level was increased upon the administration of curcumin along with NDEA. The results obtained for the comet assay in rat hepatocytes and blood lymphocytes showed a significant dose-dependent decrease in the mean tail length. The micronucleus assay performed on rat hepatocytes also showed a dose-dependent reduction in the frequency of micronucleated cells along with curcumin administration. These results suggest that curcumin has a protective role against NDEA-induced toxicity in albino rats.  相似文献   
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BackgroundLittle is known on the current global prevalence of atopic dermatitis (AD) in the pediatric population.ObjectiveTo estimate the real-world global prevalence of AD in the pediatric population and by disease severity.MethodsThis international, cross-sectional, web-based survey of children and adolescents (6 months to <18 years old) was conducted in the following 18 countries: North America (Canada, United States), Latin America (Argentina, Brazil, Columbia, Mexico), Europe (France, Germany, Italy, Spain, United Kingdom), Middle East and Eurasia (Israel, Saudi Arabia, Turkey, United Arab Emirates, Russia), and East Asia (Japan, Taiwan). Prevalence was determined using the following 2 definitions: (1) diagnosed as having AD according to the International Study of Asthma and Allergies in Childhood (ISAAC) criteria and self- or parent-report of ever being told by a physician that they or their child child had AD (eczema); and (2) reported AD based on the ISAAC criteria only. Severity was assessed using the Patient Global Assessment (PtGA) and Patient-Oriented Eczema Measure (POEM).ResultsAmong 65,661 responders, the 12-month diagnosed AD prevalence (ISAAC plus self-reported diagnosis) ranged from 2.7% to 20.1% across countries; reported AD (ISAAC only) was 13.5% to 41.9%. Severe AD evaluated with both PtGA and POEM was generally less than 15%; more subjects rated AD as mild on PtGA than suggested by POEM. No trends in prevalence were observed based on age or sex; prevalence was generally lower in rural residential settings than urban or suburban.ConclusionThis global survey in 18 countries revealed that AD affects a substantial proportion of the pediatric population. Although prevalence and severity varied across age groups and countries, less than 15% had severe AD.  相似文献   
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