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1.
Int J Biomed Imaging ; 2015: 519024, 2015.
Article in English | MEDLINE | ID: mdl-25977682

ABSTRACT

We propose an algorithm for vessel extraction in retinal images. The first step consists of applying anisotropic diffusion filtering in the initial vessel network in order to restore disconnected vessel lines and eliminate noisy lines. In the second step, a multiscale line-tracking procedure allows detecting all vessels having similar dimensions at a chosen scale. Computing the individual image maps requires different steps. First, a number of points are preselected using the eigenvalues of the Hessian matrix. These points are expected to be near to a vessel axis. Then, for each preselected point, the response map is computed from gradient information of the image at the current scale. Finally, the multiscale image map is derived after combining the individual image maps at different scales (sizes). Two publicly available datasets have been used to test the performance of the suggested method. The main dataset is the STARE project's dataset and the second one is the DRIVE dataset. The experimental results, applied on the STARE dataset, show a maximum accuracy average of around 94.02%. Also, when performed on the DRIVE database, the maximum accuracy average reaches 91.55%.

2.
Rev. méd. Chile ; 138(12): 1510-1516, dic. 2010. tab
Article in Spanish | LILACS | ID: lil-583047

ABSTRACT

Background: Semen analysis is one of the parameters used to predict male fertility. Semen can be altered by environmental pollutants; therefore it could be used as a biological marker of exposure in contaminated areas. Aim: To analyze the spermogram values in a sample of healthy young males, residing in Arica, Chile. Material and methods: One hundred and two healthy university students volunteers aged 18 to 30 years answered a questionnaire about fertility, habits and andrologic diseases and provided a semen sample. Within three hours after ejaculation, semen volume, pH, sperm concentration, motility and morphology were analyzed. Results: Six percent of volunteers had offspring, 1 percent declared to be infertile, 32 percent smoked and 78 percent con-sumed alcohol. Semen pH was 7.6 ± 0.5, volume, 2.9 ± 1.6 ml, sperm concentration, 62.8 ± 62.3 x 10(6)/ml, normal morphology, 15.0 ± 7.9 percent, overall motility, 42.2 ± 23.2 percent and grade A motility, 19.2 ± 18.6 percent. The percentage of subjects that had normal semen values was 82 percent for total sperm count, 76 percent for sperm concentration, 72 percent for volume, 64 percent for vitality, 63 percent for pH, 57 percent for morphology, 38 percent for overall motility and 26 percent for grade A motility. Conclusions: This sample of healthy young males had a normal sperm count in comparison with international reports. However it is necessary to characterize the spermogram in uncontaminated areas of Chile to ensure that our results are within the expected values for the country.


Subject(s)
Adolescent , Adult , Humans , Male , Young Adult , Environmental Pollutants/toxicity , Fertility/drug effects , Semen Analysis , Semen/drug effects , Biomarkers/analysis , Boron/toxicity , Chile , Reproducibility of Results , Semen/physiology , Sperm Count , Sperm Motility/drug effects , Sperm Motility/physiology
3.
Rev Med Chil ; 138(12): 1510-6, 2010 Dec.
Article in Spanish | MEDLINE | ID: mdl-21526299

ABSTRACT

BACKGROUND: Semen analysis is one of the parameters used to predict male fertility. Semen can be altered by environmental pollutants; therefore it could be used as a biological marker of exposure in contaminated areas. AIM: To analyze the spermogram values in a sample of healthy young males, residing in Arica, Chile. MATERIAL AND METHODS: One hundred and two healthy university students volunteers aged 18 to 30 years answered a questionnaire about fertility, habits and andrologic diseases and provided a semen sample. Within three hours after ejaculation, semen volume, pH, sperm concentration, motility and morphology were analyzed. RESULTS: Six percent of volunteers had offspring, 1% declared to be infertile, 32% smoked and 78% consumed alcohol. Semen pH was 7.6 ± 0.5, volume, 2.9 ± 1.6 ml, sperm concentration, 62.8 ± 62.3 x 10(6)/ml, normal morphology, 15.0 ± 7.9%, overall motility, 42.2 ± 23.2 % and grade A motility, 19.2 ± 18.6%. The percentage of subjects that had normal semen values was 82% for total sperm count, 76% for sperm concentration, 72% for volume, 64% for vitality, 63% for pH, 57% for morphology, 38% for overall motility and 26% for grade A motility. CONCLUSIONS: This sample of healthy young males had a normal sperm count in comparison with international reports. However it is necessary to characterize the spermogram in uncontaminated areas of Chile to ensure that our results are within the expected values for the country.


Subject(s)
Environmental Pollutants/toxicity , Fertility/drug effects , Semen Analysis , Semen/drug effects , Adolescent , Adult , Biomarkers/analysis , Boron/toxicity , Chile , Humans , Male , Reproducibility of Results , Semen/physiology , Sperm Count , Sperm Motility/drug effects , Sperm Motility/physiology , Young Adult
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