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The relationship between DNA fragmentation and the intensity of morphologically abnormal human spermatozoa

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Asian pacific Journal of Reproduction 2024年第1期13卷 22-27页

作者： Mercedes González-Martínez Pascual sánchez-Martín Carmen López-Fernández stephen D.Johnston Jaime Gosálvez Clínica Ginemed Unidad de ReproducciónSevillaSpain Department of Biology Universidad Autónoma de MadridCantoblancoMadridSpain school of Environment The University of QueenslandGattonAustralia school of Veterinary science The University of QueenslandGattonAustralia

objective:To determine the relationship between teratozoospermia and sperm DNA fragmentation(sDF)in the human ***:This retrospective study included 100 normozoospermic men as a control cohort(abnormal forms>14%),210 patients with a high level of abnormal forms(≤4%)and 65 patients presenting with a moderate level of abnormal forms(>4%to≤14%)based on the World Health organization *** morphology was assessed using bright field *** DNA fragmentation was assessed using the sperm chromatin dispersion ***-parametric analyses were conducted to examine the relationship between abnormal sperm morphology and sperm DNA fragmentation;receiver operating characteristic(roc)analyses were conducted to assess sensitivity and specificity of this ***:A correlation analysis revealed that the higher the proportion of abnormal spermatozoa in the ejaculate,the higher the level of sDF(spearman's Rho=-0.230;Psignificant differences in the proportion of sDF were found when all cohorts were compared(Pse significant differences were also retained when the different cohorts were compared *** analysis showed a moderate but significant predictive value for sDF to differentiate patients with different levels of ***:Although analysis of a more continuous range of values for teratozoospermia would help further clarify any causal relationship with sDF,there is clearly a synergistic or coincident affiliation between these variables that needs to be acknowledged by the clinician when interpreting the spermiogram.

关键词： Teratozoospermia sperm morphology sperm DNA fragmentation Male factor Human reproduction Human fertility

Ileocolic Intussusception Prolapsing from the Rectum in von Recklinghausen's Disease

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surgical science 2012年第8期3卷 421-423页

作者： Marlén Alvite Canosa Leticia Alonso Fernández Lucía Dorado Castro rocío González López ana álvarez Gutiérrez Inmaculada Monjero Ares José Conde Vales Félix Arija Val General surgery department of Hospital Universitario Lucus Augusti Lugo Spain

Intussusception is a paediatric condition that rarely presents in adults. We report an exceptional case of ileocolic intussusception prolapsing from the rectum in an adult with Von Recklinghausen′s disease. A 31-year-old man with von Recklinghausen′s disease presented to emergency department with a history of severe abdominal pain, vomits and rectal bleeding. Abdominal computed tomography showed intestinal obstruction probably due to a sigmoidorectal intussusception. Ileum, appendix, cecum and ascending colon were found to be intussuscepting through transverse, descending and sigmoid colon and prolapsing from the rectum during an emergent laparotomy. A right hemicolectomy was performed. An anatomical pathology examination revealed a neurofibroma of the appendix as lead point for intussusception. Intussusception in adults requires early surgical resection regardless of the nature of the initial case. Neurofibroma of the appendix is very rare;although it is benign, prompt resection is recommended because of a high risk of appendicitis and malignant transformation.

关键词： Adult Intussusceptions Neurofibromatosis Von Recklinghausen′s Disease Appendiceal Neurofibroma

Modeling susceptibility to deforestation of remaining ecosystems in North Central Mexico with logistic regression

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Journal of Forestry Research 2012年第3期23卷 345-354页

作者： L.Miranda-Aragón E.J.Trevi o-Garza J.Jiménez-Pérez o.A.Aguirre-Calderón M.A.González-Tagle M.Pompa-García C.A.Aguirre-salado Facultad de Ciencias Forestales Universidad Autónoma de NuevoLeón67700Linares NLMexico Facultad de Ciencias Forestales Universidad Juárez del Estado deDurango34120Durango DgoMexico Facultad de Ingeniería Universidad Autónoma de San Luis Potosí78290San Luis Potosi SLPMexico

Determining underlying factors that foster deforestation and delineating forest areas by levels of susceptibility are of the main challenges when defining policies for forest management and planning at regional scale. The susceptibility to deforestation of remaining forest ecosystems （shrubland, temperate forest and rainforest） was conducted in the state of san Luis Potosi, located in north central Mexico. spatial analysis techniques were used to detect the deforested areas in the study area during 1993-2007. Logistic regression was used to relate explana- tory variables （such as social, investment, forest production, biophysical and proximity factors） with susceptibility to deforestation to construct predictive models with two focuses： general and by biogeographical zone In all models, deforestation has positive correlation with distance to rainfed agriculture, and negative correlation with slope, distance to roads and distance to towns. other variables were significant in some cases, but in others they had dual relationships, which varied in each biogeographi- cal zone. The results show that the remaining rainforest of Huasteca region is highly susceptible to deforestation. Both approaches show that more than 70% of the current rainforest area has high and very high levels of susceptibility to deforestation. The values represent a serious concern with global warming whether tree carbon is released to atmos- phere. However, after some considerations, encouraging forest environ- mental services appears to be the best alternative to achieve sustainableforest management.

关键词： GIs land use change proximity factors statistical modeling roc curve regional forest planning

An Assessment of Rare Earth Aluminates as Possible Radiation shields for Artificial satellites in Low Earth orbit

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Materials sciences and Applications 2018年第4期9卷 430-439页

作者： Ernesto ortiz José Francisco Valdés-Galicia rocío García Lorenzo M. Martínez de la Escalera Marcos Anzorena Lorenzo Martínez-Gómez Instituto de Ciencias Físicas Universidad Nacional Autónoma de México Cuernavaca Mexico Instituto de Geofísica Universidad Nacional Autónoma de México Ciudad de México Mexico Corrosión y Protección (CyP) Ciudad de México Mexico

Charged particles injected into dielectric material of artificial satellites may cause data flipping, command errors and charges in dielectric material properties. In this work we report the results of an evaluation of rare earth aluminates as possible radiation shields for its application in Low Earth orbit (LEo) satellite construction. With help of Geant4 software, we calculated the radiation dose that a target receives at a typical LEo (685 km) as a function of the shield thickness. The target used was a silicon plate, the shields used were hollow cubes of rare earth aluminate walls (YAlo3, LaAlo3, NdAlo3 and GdAlo3), and we also used aluminium oxide (Al2o3). The radiation source was the measured fluxes of electron and proton with a spectrum corresponding to a LEo. We found that of the total radiation dose received by the target without shield is 5847 microGy/hour, of which, the electrons contribute with 94.9% and the protons with 5.1%. The rare earth aluminates are a better shield than the Al2o3 to protect a target against the radiation that permeates a LEo near to equator.

关键词： Rare Earth Aluminates Cosmic Radiation Artificial satellites

Activity optimization method in sPECT:A comparison with roc analysis

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Journal of Zhejiang University-science B(Biomedicine & Biotechnology) 2006年第12期7卷 947-956页

作者： DíAZ Marlén Pérez RIZo oscar Díaz DíAZ Adlin López APARICIo Eric Estévez DíAZ Reinaldo Roque Center for studies on Electronics & Info Tech. Images Group Central University of Las Villas Santa Clara 54830 Cuba Department of Nuclear Physics Institute for Sciences and Advanced Technology Havana 10400 Cuba Department of Nuclear Medicine Cardiovascular Surgery Institute Havana 10400 Cuba Department of Nuclear Medicine University Hospital Celestino Hernández Santa Clara 50200 Cuba

A discriminant method for optimizing activity in nuclear medicine studies is validated by comparison with roc （received operating characteristic）-curves. The method is tested in 21 single photon emission computerized tomography （sPECT）, performed with a cardiac phantom. Three different lesions （Lb L2 and L3） were placed in the myocardium-wall by pairs fbr each sPECT. Three activities （84, 37 or 18.5 MBq） of 99mTc were used as background. Linear discriminant analysis was used to select the parameters that characterize image quality among the measured variables in the images [（Background-to-Lesion （B/Li） and signal-to-Noise （s/N） ratios）]. Two clusters with different image quality （P=0.021 ） were obtained. The ratios B/Lj, B/L2 and B/L3 are the parameters used to construct the function with 100% of cases correctly classified into the clusters. The value of 37 MBq was the lowest tested activity for which good results for the B/Li ratios were obtained. The result coincides with the applied roc-analysis （r=0.89）.

关键词： Activity optimization Image quality sPECT Discriminant analysis roc curves

Genetic Diversity of Great Dane Breed Using Ten Microsatellites: Impact of Breeding Control over the Breeding Line

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open Journal of Genetics 2014年第2期4卷 78-86页

作者： Gino Noris Carla santana Mariana Herrán-Aguirre Marco Antonio Meraz-Ríos Mario Pérez-Martínez Carlos Esquivel-Lacroix Leonor C. Acosta-saavedra Eduardo Rodríguez María de la Paz Juaréz Emma s. Calderón-Aranda rocío Gómez BIMoDI (Biología Molecular Diagnóstica) Querétaro Qro. México Departamento de Biomedicina Molecular Cinvestav-IPN México D.F. México Departamento de Morfología Facultad de Medicina Veteri-naria y Zootecnia Universidad Nacional Autónoma de México México D.F. México Departamento de Reproducción Facultad de Medicina Vete-rinaria y Zootecnia Universidad Nacional Autónoma de México México D.F. México Departamento de Toxicología Cinvestav-IPN. Av. Instituto Politécnico Nacional 2508 Col. San Pedro Zacatenco México D.F. México

The American Kennel Club and the Fédération Cynologique Internationale recognize two phenotypic variants of Great Dane breed denominated American and European varieties. Historically, these varieties have been segregated according to morphological characteristics. In an attempt to obtain a better characterization, breeders have been interested in the genetic parameters that could evaluate the within-breed diversity. In this document, we studied the genetic structure of Great Dane breed with 10 sTR markers in 88 dogs using capillary electrophoresis. Cluster analysis, population differentiation and phylogenetic analyses revealed that American and European varieties are genetically independent. Nevertheless, within the American variety a genetic stratification was found. Additionally, a high misclassification (28%) was detected, which could be due to wrong registration or false paternity. our results support the importance to deem genetic markers as useful tools in breeding control. similarly, these studies serve as an accurate reference to establish standards by dog breeding associations and for choosing among dogs for inter-breeding. Nevertheless, genetic tools are only a complement of morphological methods, since both are reshuffling the control over the breeding line. Notwithstanding, this database provides an overall and scape concerning the impact of genetic diversity within-breed. Unmistakably, more databases are needed to increase the quality of the breeding line as well as the number of sTR in order to study, with more detail, the genetic structure in the Great Dane race.

关键词： Genetic structure Great Dane Varieties Microsatellites Population Genetics Population stratification

Miniscrew appliances and their use in orthodontics

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open Journal of stomatology 2013年第1期3卷 103-108页

作者： rocío Molina-solana R. M. Yanez-Vico Alejandro Iglesias-Linares Daniel Torres-Lagares Enrique solano-Reina Department of stomatology University of SevilleSevilleSpain

Anchorage is an important factor in orthodontics and must be properly managed for a successful treatment outcome. orthodontists have historically used many devices to prevent unwanted tooth movement. The use of miniscrews as a source of skeletal anchorage has become routine in present-day orthodontic practice. skeletal anchorage opens up alternative treatments, to borderline surgery patients for example, who can now be treated by taking advantage of the biomechanical properties of miniscrews. Because they are bone-borne and provide excellent control over tooth movement in the three spatial planes of movement, mini-implants can be used to serve many purposes in addition to anchorage. Therefore, a variety of successful mini-implant appliances are explained in relation to the three planes of movement: sagittal, vertical, and transverse. The aim of this review is to illustrate the clinical versatility of miniscrews in the three spatial planes of malocclusion in orthodontic and orthopedic management and to define clinical guidelines for the selection, application and biomechanics of mini-implants.

关键词： Miniscrew Mini-implant orthodontics Anchorage

Emotions and stressing situations Adaptation of Nursing students in the New Normality

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Health 2022年第7期14卷 766-774页

作者： Diana Cecilia Tapia-Pancardo Nancy Areli Martínez-Rangel rocío Marisol Romero-salgado José Luis Cadena-Anguiano Rafael Villalobos-Molina División de Investigación y Posgrado Unidad de Biomedicina Facultad de Estudios Superiores Iztacala Universidad Nacional Autónoma de México Tlalnepantla México Carrera de Enfermería Facultad de Estudios Superiores Iztacala Universidad Nacional Autónoma de México Tlalnepantla México Carrera de odontología Facultad de Estudios Superiores Iztacala Universidad Nacional Autónoma de México Tlalnepantla México

Background: New normality is uncertain in every sense, specifically in education and for many health disciplines. Being immersed in CoVID-19 pandemics brought serious consequences for mental health, and is very important to handle emotions and stress coping strategies to obtain positive outcomes. objective: To identify the most frequent emotions, as well as the adaptation strategies to the new normality faced by the students of nursing. Methods: Qualitative and phenomenological research, with the participation of 20 students from both genders in the middle term of nursing career at Faculty of Higher studies Iztacala, National Autonomous University of Mexico, from August to November 2021. Information was collected from a focal group for ten sessions;analysis was according to De souza Minayo, and there was a signed informed consent letter from participants. Results: Four categories emerged with sub-categories. Category I Maximized emotions. sub-categories: 1) Frustration, anger, disappointment;2) Personal disappointment, hopelessness, uncertainty;3) Depression. Category II support elements close to the new normality. sub-categories: 1) Family communication;2) Education for mental and physical health. Category III stressing situations that exceeded the student. sub-category: Disease in lovely ones. Category IV stress coping strategies. sub-categories: 1) Friends and relatives that help to get better;2) Family values. Informers pointed out to have maximized emotion, and having no self-control on its negative outcomes occurred;in addition, the situation was not favorable at home with several losses of loved ones, as well as a poor economy that threatened students to give up studies. Conclusion: Emotions facing this new normality are very important and should be attended to, their proper handling will result in a new learning of socio-emotional abilities, stress coping strategies development, better adaptation and informed decisions taken.

关键词： Emotions stressing situations Adaptation Nursing students New Normality

Exploratory study on microRNA profiles from plasma-derived extracellular vesicles in Alzheimer’s disease and dementia with Lewy bodies

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Translational Neurodegeneration 2019年第1期8卷 382-398页

作者： ana Gámez-Valero Jaume Campdelacreu Dolores Vilas Lourdes Ispierto ramón Reñé ramiroÁlvarez MPilar Armengol Francesc E.Borràs Katrin Beyer Department of Pathology Health Sciences Research Institute Germans Trias i Pujol(IGTP)Universitat Autònoma de BarcelonaBadalona 08916Spain REMAR-IVECAT group Health Sciences Research Institute Germans Trias i Pujol(IGTP)08916 BadalonaSpain Department of Neurology Hospital Universitari de BellvitgeL’Hospitalet de Llobregat 08907Spain Department of Neurology Hospital Universitari Germans Trias i Pujol08916 BadalonaSpain Genomic and Microscopy facilities Health Sciences Research Institute Germans Trias i Pujol(IGTP)08916 BadalonaSpain Department of Cell Biology Physiology and ImmunologyUniversitat Autònoma de Barcelona(UAB)BarcelonaSpain

Background:Because of the increasing life expectancy in our society,aging-related neurodegenerative disorders are one of the main issues in global *** of these diseases are characterized by the deposition of misfolded proteins and a progressive cognitive *** these diseases,Alzheimer’s disease(AD)and dementia with Lewy bodies(DLB)are the most common types of degenerative *** both show specific features,an important neuropathological and clinical overlap between them hampers their correct *** this work,we identified molecular biomarkers aiming to improve the misdiagnosis between both ***:Plasma extracellular vesicles(EVs)-from DLB,AD and healthy controls-were isolated using size-exclusion chromatography(sEC)and characterized by flow cytometry,Nanoparticle Tracking analysis(NTA)and cryo-electron *** Generation sequencing(NGs)and related bibliographic search was performed and a selected group of EV-associated microRNAs(miRNAs)was analysed by ***:Results uncovered two miRNAs(hsa-miR-451a and hsa-miR-21-5p)significantly down-regulated in AD samples respect to DLB patients,and a set of four miRNAs(hsa-miR-23a-3p,hsa-miR-126-3p,hsa-let-7i-5p,and hsamiR-151a-3p)significantly decreased in AD respect to *** two miRNAs showing decreased expression in AD in comparison to DLB provided area under the curve(AUC)values of 0.9 in roc curve analysis,thus suggesting their possible use as biomarkers to discriminate between both *** gene analysis of these miRNAs using prediction online tools showed accumulation of phosphorylation enzymes,presence of proteasome-related proteins and genes involved in cell death among ***:our data suggest that plasma-EV associated miRNAs may reflect a differential profile for a given dementia-related disorder which,once validated in larger cohorts of patients,could help to improve the differential diagnosis of DLB versus AD.

关键词： Neurodegenerative disorders Biomarker Exosomes Next generation sequencing Extracellular vesicles