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Does cryptic dichromatism exist in the Saffron Finch(Sicalis flaveola)?Colorimetric variables and the avian visual model
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作者 Lorena Cruz-Bernate Camilo Espinosa-Bravo Hector Fabio Rivera-Gutierrez 《Avian Research》 SCIE CSCD 2023年第3期405-415,共11页
Sexual dichromatism,a particular type of sexual dimorphism,occurs in several species and has been associated with sexual selection.In some cases,the differences are so small that they are imperceptible to humans,but p... Sexual dichromatism,a particular type of sexual dimorphism,occurs in several species and has been associated with sexual selection.In some cases,the differences are so small that they are imperceptible to humans,but possibly detected by birds.The objective measurement of color with spectrophotometers and detailed analyses according to the perception ability of the avian eye have revealed that some species that were once considered to be monochromatic,are in fact dichromatic and able to perceive these differences.In the tropics,the Saffron Finch(Sicalis flaveola) does not present marked sexual dimorphism in coloration,which makes studies in behavioral ecology,natural history and population dynamics difficult.To assess whether there is dichromatism in the species,the reflectance(between 300 and 700 nm) of ten body regions was measured in 196 wild adults in Cali-Colombia.Sex was determined using the CHD1 gene on the sex chromosomes.Reflectance spectra were analyzed using:colorimetric variables and the avian visual model.We found that reflectance shows a bimodal curve in all body regions,except the crown.Males presented higher reflectance at long wavelengths,while for females this occurred in ultraviolet wavelengths.For the visual model,we found that there are significant intrasexual differences;however only in crown coloration is there a possible perceived difference between sexes.We conclude that in the Saffron Finch there are color differences between the sexes in all regions considering the physical phenomenon(reflectance),but in general,when evaluating color perception(avian visual model),there are no differences between the sexes in most of the body regions.The intrasexual differences are significant,indicating the possibility of these being signals that influence social interactions in the species. 展开更多
关键词 Carotenoids Color discrimination Colombia Intrasexual signals Social selection Tanagers Tropical region
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Metabolomics for the diagnosis of bladder cancer: A systematic review
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作者 Herney Andrés García-Perdomo Angélica María Dávila-Raigoza Fernando Korkes 《Asian Journal of Urology》 CSCD 2024年第2期221-241,共21页
Objective: Metabolomics has been extensively utilized in bladder cancer (BCa) research, employing mass spectrometry and nuclear magnetic resonance spectroscopy to compare various variables (tissues, serum, blood, and ... Objective: Metabolomics has been extensively utilized in bladder cancer (BCa) research, employing mass spectrometry and nuclear magnetic resonance spectroscopy to compare various variables (tissues, serum, blood, and urine). This study aimed to identify potential biomarkers for early BCa diagnosis.Methods: A search strategy was designed to identify clinical trials, descriptive and analytical observational studies from databases such as Medline, Embase, Cochrane Central Register of Controlled Trials, and Latin American and Caribbean Literature in Health Sciences. Inclusion criteria comprised studies involving BCa tissue, serum, blood, or urine profiling using widely adopted metabolomics techniques like mass spectrometry and nuclear magnetic resonance. Primary outcomes included description of metabolites and metabolomics profiling in BCa patients and the association of metabolites and metabolomics profiling with BCa diagnosis compared to control patients. The risk of bias was assessed using the Quality Assessment of Studies of Diagnostic Accuracy.Results: The search strategy yielded 2832 studies, of which 30 case-control studies were included. Urine was predominantly used as the primary sample for metabolite identification. Risk of bias was often unclear inpatient selection, blinding of the index test, and reference standard assessment, but no applicability concerns were observed. Metabolites and metabolomics profiles associated with BCa diagnosis were identified in glucose, amino acids, nucleotides, lipids, and aldehydes metabolism.Conclusion: The identified metabolites in urine included citric acid, valine, tryptophan, taurine, aspartic acid, uridine, ribose, phosphocholine, and carnitine. Tissue samples exhibited elevated levels of lactic acid, amino acids, and lipids. Consistent findings across tissue, urine, and serum samples revealed downregulation of citric acid and upregulation of lactic acid, valine, tryptophan, taurine, glutamine, aspartic acid, uridine, ribose, and phosphocholine. 展开更多
关键词 METABOLITE Metabolomics Bladder cancer Metabolomicsprofile
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Canopy Storage Implications on Interception Loss Modeling
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作者 Cesar Véliz-Chávez Carlos Alberto Mastachi-Loza +2 位作者 Enrique González-Sosa Rocio Becerril-Pina Norma Maricela Ramos-Salinas 《American Journal of Plant Sciences》 2014年第20期3032-3048,共17页
A rainfall interception methodology was implemented in a deciduous Ficus benjamina (L.) tree to evaluate the interception loss, as well as the dynamics on canopy storage capacity (S) and free through fall (ρ). Measur... A rainfall interception methodology was implemented in a deciduous Ficus benjamina (L.) tree to evaluate the interception loss, as well as the dynamics on canopy storage capacity (S) and free through fall (ρ). Measurements of gross precipitation (Pg), through fall and meteorological data were recorded every 5 minutes. Nineteen individual storms from summer to autumn 2005, and twenty one in spring to autumn, 2006 were analyzed. For the studied period, 151.59 mm and 203.35 mm of rainfall occurred on 2005 and 2006 respectively. Canopy interception was 59.46% and 70.98% of Pg for the first and second year. Throughfall data recorded during 2005 were ?38.14% (of Pg) and 27.21% (of Pg) for 2006. The throughfall and gross precipitation relationship yielded S = 1.50 mm for the 2005 data. In 2006 storms were analyzed in detail, where ρ and S varied in a range from 0.10 to 0.64 and from 1.00 to 2.03 mm, respectively. Moreover, application of the Rutter and Gash models with two years of rainfall data (2005-2006) from the study area indicated an underestimation and overestimation of 69% and 88%, respectively. The slightly best prediction of the interception loss was obtained with the Gash model. Yet S and ρ change significantly due to wind speed, temperature, rainfall intensity and seasonal vegetation development. 展开更多
关键词 INTERCEPTION Storage Capacity THROUGHFALL Gash Model
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Implementation outcomes of a sensory integration therapy program with computerized dynamic posturography in patients with balance and sensory dysfunction
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作者 Francisco Javier Gonzalez Eslait Paola Andrea Escudero Trivino +2 位作者 Yaidy Viviana Giraldo Vergara Monica Andrea Morales Garcia Vanessa Fernanda Lucero Gutierrez 《Journal of Otology》 CSCD 2023年第1期26-32,共7页
Objective:We describe the first-year implementation experience of an Instrumented Sensory Integration Therapy Program in Audiological&Balance Center patients.Design:This is a retrospective descriptive study.Partic... Objective:We describe the first-year implementation experience of an Instrumented Sensory Integration Therapy Program in Audiological&Balance Center patients.Design:This is a retrospective descriptive study.Participants included Seventy-three adults with diagnoses of acute,episodic,or chronic vestibular syndromes.They were classified into the following two groups:group 1 included 46 individuals treated with ISIT plus VRT,and group 2 included 27 individuals treated only with ISIT.Results:The Sensory Organization Test(SOT)for both groups showed a statistical significance for all three sensory inputs;visual systems(G1:p=0.0003;G2:p=0.0337),vestibular system(G1:p<0.0001;G2:p=0.0003),and balance as demonstrated by compound balance score(G1:p<0.0001;G2:p=0.0035),and balance percentage deficit(G1:p<0.0001;G2:p=0.0078).Conclusions:The severity and complexity of functional neurological disorders in the context of vestibular syndromes seem to require between 10 and 20 therapy sessions,and combined ISIT plus VRT appears to be more effective than ISIT as a monotherapy. 展开更多
关键词 POSTUROGRAPHY Vestibular rehabilitation therapy Dizziness handicap inventory
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Fragile X Messenger Ribonucleoprotein 1(FMR1), a novel inhibitor of osteoblast/osteocyte differentiation, regulates bone formation, mass, and strength in young and aged male and female mice
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作者 Padmini Deosthale Julián Balanta-Melo +12 位作者 Amy Creecy Chongshan Liu Alejandro Marcial Laura Morales Julita Cridlin Sylvia Robertson Chiebuka Okpara David J.Sanchez Mahdi Ayoubi Joaquín N.Lugo Christopher J.Hernandez Joseph M.Wallace Lilian I.Plotkin 《Bone Research》 SCIE CAS CSCD 2023年第2期384-397,共14页
Fragile X Messenger Ribonucleoprotein 1(FMR1)gene mutations lead to fragile X syndrome,cognitive disorders,and,in some individuals,scoliosis and craniofacial abnormalities.Four-month-old(mo)male mice with deletion of ... Fragile X Messenger Ribonucleoprotein 1(FMR1)gene mutations lead to fragile X syndrome,cognitive disorders,and,in some individuals,scoliosis and craniofacial abnormalities.Four-month-old(mo)male mice with deletion of the FMR1 gene exhibit a mild increase in cortical and cancellous femoral bone mass.However,consequences of absence of FMR1 in bone of young/aged male/female mice and the cellular basis of the skeletal phenotype remain unknown.We found that absence of FMR1 results in improved bone properties with higher bone mineral density in both sexes and in 2-and 9-mo mice.The cancellous bone mass is higher only in females,whereas,cortical bone mass is higher in 2-and 9-mo males,but higher in 2-and lower in 9-mo female FMR1-knockout mice.Furthermore,male bones show higher biomechanical properties at 2mo,and females at both ages.Absence of FMR1 increases osteoblast/mineralization/bone formation and osteocyte dendricity/gene expression in vivo/ex vivo/in vitro,without affecting osteoclasts in vivo/ex vivo.Thus,FMR1 is a novel osteoblast/osteocyte differentiation inhibitor,and its absence leads to age-,site-and sex-dependent higher bone mass/strength. 展开更多
关键词 female MESSENGER AGILE
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In vitro effect of amoxicillin and clarithromycin on the 3' region of cagA gene in Helicobacter pylori isolates 被引量:5
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作者 Javier Andrés Bustamante-Rengifo Andrés Januer Matta +1 位作者 Alvaro Pazos Luis Eduardo Bravo 《World Journal of Gastroenterology》 SCIE CAS 2013年第36期6044-6054,共11页
AIM:To evaluate the in vitro effect of amoxicillin and clarithromycin on the cag pathogenicity island(cag PAI).METHODS:One hundred and forty-nine clinical isolates of Helicobacter pylori(H.pylori)cultured from gastric... AIM:To evaluate the in vitro effect of amoxicillin and clarithromycin on the cag pathogenicity island(cag PAI).METHODS:One hundred and forty-nine clinical isolates of Helicobacter pylori(H.pylori)cultured from gastric biopsies from 206 Colombian patients with dyspeptic symptoms from a high-risk area for gastric cancer were included as study material.Antimicrobial susceptibility was determined by the agar dilution method.Resistant isolates at baseline and in amoxicillin and clarithromycin serial dilutions were subjected to genotyping(cagA,vacA alleles s and m),Glu-Pro-Ile-Tyr-Ala(EPIYA)polymerase chain reaction and random amplified polymorphic DNA(RAPD).Images of the RAPD amplicons were analyzed by Gel-Pro Analyzer 4.5program.Cluster analyses was done using SPSS 15.0statistical package,where each of the fingerprint bands were denoted as variables.Dendrograms were designed by following Ward’s clustering method and the estimation of distances between each pair of H.pylori isolates was calculated with the squared Euclidean distance.RESULTS:Resistance rates were 4%for amoxicillin and 2.7%for clarithromycin with 2%double resistances.Genotyping evidenced a high prevalence of the genotype cagA-positive/vacA s1m1.The 3’region of cagA gene was successfully amplified in 92.3%(12/13)of the baseline resistant isolates and in 60%(36/60)of the resistant isolates growing in antibiotic dilutions.Upon observing the distribution of the number of EPIYA repetitions in each dilution with respect to baseline isolates,it was found that in 61.5%(8/13)of the baseline isolates,a change in the number of EPIYA repetitions lowered antibiotic pressure.The gain and loss of EPIYA motifs resulted in a diversity of H.pylori subclones after bacterial adjustment to changing conditions product of antibiotic pressure.RAPD PCR evidenced the close clonal relationship between baseline isolates and isolates growing in antibiotic dilutions.CONCLUSION:Antibiotic pressure does not induce loss of the cag pathogenicity island,but it can leadin most cases-to genetic rearrangements within the3’region cagA of the founding bacteria that can affect the level of tyrosine phosphorylation impacting on its cellular effects and lead to divergence of cagA-positive subclones. 展开更多
关键词 HELICOBACTER pylori Antimicrobial susceptibility cag PATHOGENICITY island CAGA 3’region Random amplified POLYMORPHIC DNA-polymerase chain reaction
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Risk factors of gastric cancer specific for tumor location and histology in Cali,Colombia 被引量:11
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作者 Francia Campos Gabriel Carrasquilla +5 位作者 Chihaya Koriyama Mauricio Serra Edwin Carrascal Tetsuhiko Itoh Mitsuharu Nomoto Suminori Akiba 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第36期5772-5779,共8页
AIM: To examine histology- and tumor-location specific risk factors of gastric cancer (GC). METHODS: This was a case-control study. The study subjects were 216 GC patients newly diagnosed during the period 2000-2002 a... AIM: To examine histology- and tumor-location specific risk factors of gastric cancer (GC). METHODS: This was a case-control study. The study subjects were 216 GC patients newly diagnosed during the period 2000-2002 and 431 controls selected from non-cancer patients matching in age, gender, and hospital. We obtained information on lifestyles, dietary habits, and others by a questionnaire. RESULTS: The subjects who were not eldest among his/her siblings were at a slightly elevated GC risk (OR 1.3; 95% CI 0.8-2.0). Salting meals before tasting was related to an increased GC risk (OR 3.5; 95% CI 1.6- 7.3). Frequent consumptions of fruits (OR 0.3; 95% CI 0.1-1.0) and vegetables (OR 0.3; 95% CI 0.1-1.0) were related to decreased GC risks. On the other hand, frying foods (OR 1.9; 95% CI 1.0-3.6) and cooking with coal (OR 1.8; 95% CI 1.3-2.6) were related to increased GC risks. Neither Lauren’s histological classification (intestinal and diffuse types) nor tumor location significantly affected those associations except birth order. The subjects who were not eldest among his/her siblings had an increased risk of GCs in the distal and middle thirds, and their ORs were 1.7 (95% CI 1.0-2.8) and 1.9 (95% CI 0.8-4.3), respectively. The corresponding OR in the upper third stomach was 0.3 (95% CI 0.1-0.9). The differences of those three ORs were statistically significant (P = 0.010). CONCLUSION: The present study shows that birth or- der, salt intake, consumption of fruits and vegetables, the type of cooking, and cigarette smoking are related to GC risk. In histology and tumor-location specific analy- ses, non-eldest person among their siblings is related to an increased GC risk in the distal and middle thirds of the stomach, and is related to a decreased GC risk in the cardia. 展开更多
关键词 胃癌 组织学 哥伦比亚 病理机制
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Punctual mutations in 23S rRNA gene of clarithromycinresistant Helicobacter pylori in Colombian populations 被引量:5
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作者 Andrés Jenuer Matta Diana Carolina Zambrano Alvaro Jairo Pazos 《World Journal of Gastroenterology》 SCIE CAS 2018年第14期1531-1539,共9页
AIM To characterize punctual mutations in 23S rRNA gene of clarithromycin-resistant Helicobacter pylori(H. pylori) and determine their association with therapeutic failure.METHODS PCR products of 23S rRNA gene V domai... AIM To characterize punctual mutations in 23S rRNA gene of clarithromycin-resistant Helicobacter pylori(H. pylori) and determine their association with therapeutic failure.METHODS PCR products of 23S rRNA gene V domain of 74 H. pylori isolates; 34 resistant to clarithromycin(29 from a low-risk gastric cancer(GC) population: TumacoColombia, and 5 from a high-risk population: TuquerresColombia) and 40 from a susceptible population(28 from Tumaco and 12 from Túquerres) were sequenced using capillary electrophoresis. The concordance between mutations of V domain 23S rRNA gene of H. pylori and therapeutic failure was determined using the Kappa coefficient and Mc Nemar's test was performed to determine the relationship between H. pylori mutationsand clarithromycin resistance.RESULTS23S rRNA gene from H. pylori was amplified in 56/74 isolates, of which 25 were resistant to clarithromycin(20 from Tumaco and 5 from Túquerres, respectively). In 17 resistant isolates(13 from Tumaco and 4 from Túquerres) the following mutations were found: A1593 T1, A1653 G2, C1770 T, C1954 T1, and G1827 C in isolates from Tumaco, and A2144 G from Túquerres. The mutations T2183 C, A2144 G and C2196 T in H. pylori isolates resistant to clarithromycin from Colombia are reported for the first time. No association between the H. pylori mutations and in vitro clarithromycin resistance was found. However, therapeutic failure of eradication treatment was associated with mutations of 23S rRNA gene in clarithromycin-resistant H. pylori(κ = 0.71).CONCLUSION The therapeutic failure of eradication treatment in the two populations from Colombia was associated with mutations of the 23S rRNA gene in clarithromycinresistant H. pylori. 展开更多
关键词 CLARITHROMYCIN In VITRO resistance Point mutation HELICOBACTER PYLORI Gastric cancer 23S rRNA
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Genomic variability of Helicobacter pylori isolates of gastric regions from two Colombian populations 被引量:2
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作者 Andrés Jenuer Matta Alvaro Jairo Pazos +1 位作者 Javier Andrés Bustamante-Rengifo Luis Eduardo Bravo 《World Journal of Gastroenterology》 SCIE CAS 2017年第5期800-809,共10页
AIM To compare the genomic variability and the multiple colonization of Helicobacter pylori(H. pylori) in patients with chronic gastritis from two Colombian populations with contrast in the risk of developing gastric ... AIM To compare the genomic variability and the multiple colonization of Helicobacter pylori(H. pylori) in patients with chronic gastritis from two Colombian populations with contrast in the risk of developing gastric cancer(GC): Túquerres-Nari?o(High risk) and Tumaco-Nari?o(Low risk).METHODS Four hundred and nine patients from both genders with dyspeptic symptoms were studied. Seventy-two patients were included in whom H. pylori was isolated from three anatomic regions of the gastric mucosa,(31/206) of the high risk population of GC(Túquerres) and(41/203) of the low risk population of GC(Tumaco). The isolates were genotyped by PCR-RAPD. Genetic diversity between the isolates was evaluated by conglomerates analysis and multiple correspondence analyses. RESULTS The proportion of virulent genotypes of H. pylori was 99% in Túquerres and 94% in Tumaco. The coefficient of similarity of Nei-Li showed greater genetic diversityamong isolates of Túquerres(0.13) than those of Tumaco(0.07). After adjusting by age, gender and type of gastritis, the multiple colonization was 1.7 times more frequent in Túquerres than in Tumaco(P = 0.05).CONCLUSION In Túquerres, high risk of GC there was a greater probability of multiple colonization by H. pylori. From the analysis of the results of the PCR-RAPD, it was found higher genetic variability in the isolates of H. pylori in the population of high risk for the development of GC. 展开更多
关键词 Helicobacter pylori 致病力小岛 cag CAGA VACA 多重殖民 PCR-RAPD
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Effect of low level laser therapy on dental pulp during orthodontic movement 被引量:2
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作者 ngela Domínguez Rosa Emilia Ballesteros +1 位作者 Jairo Hernán Viáfara Oscar Mario Tamayo 《World Journal of Methodology》 2013年第2期19-26,共8页
AIM: To validate the protocol described here to be used in future clinical trials related to the effect of laser therapy on dental pulp. METHODS: Histologically treated samples from eight human healthy premolar teeth ... AIM: To validate the protocol described here to be used in future clinical trials related to the effect of laser therapy on dental pulp. METHODS: Histologically treated samples from eight human healthy premolar teeth obtained from the middle root level were distributed in four groups: group 1(G1) absolute control; group 2(G2) only laser irradiation; group 3(G3) exposed only to orthodontics; and group 4(G4) treated with orthodontics and laser. Laser treatment was performed at 830 nm wavelength, 100 mW(energy 80 J/cm2, 2.2 J), for 22 s in the vestibular surface and 22 s in the palatal surface, 1 mm away from the dental root mucosa. Three staining methods were performed: hematoxylin-eosin(HE), Masson's Trichrome method and Gomori's method.RESULTS: The pulp histology parameters were evaluated and the results classified in to 3 parts: an inflammatory response, soft tissue response(dental pulp) and hard tissue response(dentin and predentin). There was no inflammation(chronic or acute) in any of the evaluated groups. The zones of pulp necrosis were found in one premolar of G3 and in one of G4; in groups G2 and G4 there was higher angiogenesis than in the other two groups. G4 group presented the highest level of vascularization. A reduced nerve density was observed in G3. A G2 specimen showed increased nerve density. A higher rate of calcification was observed in G1 compared to G2. Denticles, either real or false, were observed in G1, G2 and G3. Sclerosis of dentin and focal dentin loss was observed among all the groups. Secondary dentin was present in one sample in G1 and G2. A necrosis zone was found in one sample of G3 and G4. No differences between groups were observed in the odontoblast irregularity layer but the layer was wider in the group treated with laser only. A notable difference was detected in reduction of the cell-free layer between the groups G1 and G4. The findings in pulp tissue favor its adaptative response against dental movement induced by orthodontics. No definitive conclusions may be derived as this is a pilot study. CONCLUSION: The protocol described here was shown to be an effective method to evaluate changes in dental pulp submitted to low level laser in teeth under orthodontic movement. 展开更多
关键词 Low level laser therapy Pulpal Orthodontic movement Histological protocol DENTIN
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Flotation of Brazilian and Colombian Coals Using a Negative Bias 被引量:1
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作者 Irineu Brum H. Villegas +3 位作者 W. Banguero J. Guerrero C. Sampaio J. Barraza 《Journal of Chemistry and Chemical Engineering》 2013年第2期170-174,共5页
关键词 哥伦比亚 浮选柱 负偏压 巴西 煤用 煤炭储量 矿产资源 起泡剂
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Effect of homogenization process on the hardness of Zn-Al-Cu alloys 被引量:1
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作者 Jose D.Villegas-Cardenas Maribel L.Saucedo-Munoz +3 位作者 Victor M.Lopez-Hirata Antonio De Ita-De la Torre Erika O.Avila-Davila Jorge Luis Gonzalez-Velazquez 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2015年第10期1076-1081,共6页
The effect of a homogenizing treatment on the hardness of as-cast Zn–Al–Cu alloys was investigated. Eight alloy compositions were prepared and homogenized at 350 °C for 180 h, and their Rockwell 'B' har... The effect of a homogenizing treatment on the hardness of as-cast Zn–Al–Cu alloys was investigated. Eight alloy compositions were prepared and homogenized at 350 °C for 180 h, and their Rockwell 'B' hardness was subsequently measured. All the specimens were analyzed by X-ray diffraction and metallographically prepared for observation by optical microscopy and scanning electron microscopy. The results of the present work indicated that the hardness of both alloys(as-cast and homogenized) increased with increasing Al and Cu contents; this increased hardness is likely related to the presence of the θ and τ′ phases. A regression equation was obtained to determine the hardness of the homogenized alloys as a function of their chemical composition and processing parameters, such as homogenization time and temperature, used in their preparation. 展开更多
关键词 zinc–aluminum–copper alloys CASTING HARDNESS HOMOGENIZATION PHASES microstructure
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Human papillomavirus in upper digestive tract tumors from three countries 被引量:1
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作者 Andres Castillo Chihaya Koriyama +10 位作者 Michiyo Higashi Muhammad Anwar Mulazim Hussain Bukhari Edwin Carrascal Lida Mancilla Hiroshi Okumura Masataka Matsumoto Kazumasa Sugihara Shoji Natsugoe Yoshito Eizuru Suminori Akiba 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第48期5295-5304,共10页
AIM: To clarify human papillomavirus (HPV) involvement in carcinogenesis of the upper digestive tract of virological and pathological analyses. METHODS: The present study examined the presence of HPV in squamous cell ... AIM: To clarify human papillomavirus (HPV) involvement in carcinogenesis of the upper digestive tract of virological and pathological analyses. METHODS: The present study examined the presence of HPV in squamous cell carcinomas of the oral cavity (n = 71), and esophagus (n = 166) collected from Japan, Pakistan and Colombia, with different HPV exposure risk and genetic backgrounds. The viral load and physical status of HPV16 and HPV16-E6 variants were examined. Comparison of p53 and p16INK4a expression in HPV-positive and HPV-negative cases was also made. RESULTS: HPV16 was found in 39 (55%) oral carcinomas (OCs) and 24 (14%) esophageal carcinomas (ECs). This site-specific difference in HPV detection between OCs and ECs was statistically significant (P < 0.001). There was a significant difference in the geographical distribution of HPV16-E6 variants. Multiple infections of different HPV types were found in 13 ECs, but multiple infections were not found in OCs. This difference was statistically significant (P = 0.001). The geometric means (95% confidence interval) of HPV16 viral load in OCs and ECs were 0.06 (0.02-0.18) and 0.12 (0.05-0.27) copies per cell, respectively. The expression of p16INK4a proteins was increased by the presence of HPV in ECs (53% and 33% in HPV-positive and-negative ECs, respectively; P = 0.036), and the high-risk type of the HPV genome was not detected in surrounding normal esophageal mucosa of HPV-positive ECs. CONCLUSION: Based on our results, we cannot deny the possibility of HPV16 involvement in the carcinogenesis of the esophagus. 展开更多
关键词 人的乳头状瘤病毒 病毒的负担 物理地位 E6 p53 P16INK4A
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Bioactivity and Kinetic Study of <i>Jatropha curcas</i>Essential Oil Extraction Using Supercritical CO<sub>2</sub> 被引量:1
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作者 Laura Catalina Soto-Armenta Julio C. Sacramento Rivero +2 位作者 Claudia Araceli Ruiz-Mercado Azucena González-Coloma José Antonio Rocha-Uribe 《American Journal of Analytical Chemistry》 2020年第8期322-334,共13页
This study reports the extraction of <i>Jatropha curcas</i> leaves using supercritical CO<sub>2</sub>. Experiments were performed varying the pressure (13 and 20 MPa) and the temperature (50... This study reports the extraction of <i>Jatropha curcas</i> leaves using supercritical CO<sub>2</sub>. Experiments were performed varying the pressure (13 and 20 MPa) and the temperature (50°C and 60°C). The model of Sovová for supercritical fluid extraction was fitted to the experimental kinetic extraction curves. Two cell sizes were used and scale up equations compared. GC analysis showed phytol, carvacrol, and hexahydrofarnesyl acetone as major compounds in all the experiments. A maximum yield of 0.95% dry-weight basis was obtained. It was observed a maximum yield (0.95% dry-weight basis) extract obtained at 20 MPa and 50°C. The results indicated that the mass yield increased with the increase of pressure. The bioassays showed that the extract of <i>J. curcas</i> possessed toxicity against <i>Hyalomma lusitanicum</i>. 展开更多
关键词 Jatropha curcas Leaves Supercritical Fluid Scale-Up Acaricidal Activity
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Tribological Properties and Corrosion Resistance Enhancement of H13 Hot Work Steel by Means of CrN/TiN Multilayers 被引量:1
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作者 Bejarano Gaitan Gilberto Gomez Botero Maryory +2 位作者 Osorio Alberto Jaime Caicedo Anguio Julio Aperador Chaparro William 《材料科学与工程(中英文版)》 2010年第6期51-59,共9页
关键词 热作模具钢 摩擦学性能 耐腐蚀性 氮化钛 H13 性能增强 多层膜 CRN
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Resistance to the Whitefly Aleurotrachelus socialis(Hemiptera:Aleyrodidae) and SSR Marker Identification in Advanced Populations of the Hybrid Manihot esculenta subsp.Manihot flabellifolia
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作者 Arturo Carabalí James Montoya-Lerma +2 位作者 Anthony C Belloti Martin Fregene Gerardo Gallego 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第12期2217-2228,共12页
Genes resistant to Aleurotrachelus socialis were transferred to the F 1 from the interspecific hybrid wild species of Manihot flabellifolia to M.esculenta and two advanced generations of backcrosses(BC 1 and BC 2).W... Genes resistant to Aleurotrachelus socialis were transferred to the F 1 from the interspecific hybrid wild species of Manihot flabellifolia to M.esculenta and two advanced generations of backcrosses(BC 1 and BC 2).We characterized the resistance of A.socialis transferred to BC 2 parents(CW67-160,CW67-130,CW67-44),MTAI-8(BC 1),resistant(CMB9B-73) and susceptible(CMB9B-104) genotypes from contrasting pools,and resistant(MEcu-72) and susceptible(CMC-40) genotypes.Whitefly demography and biology were evaluated.SSR molecular markers associated with a phenotypic response of plant resistance were detected in segregating populations(BC 2).Results showed that although female survival time was similar on all hosts,the lowest averages of longevity,fecundity and oviposition rate were observed in the resistant control MEcu- 72,only being significantly similar to the parent CW67-130.When the BC 1 and BC 2 populations were compared,it was found that A.socialis fecundity was eight times lower on CMB9B-73 progeny than on CW67-130,expressing the highest levels of resistance to the whitefly.Ten genotypes of CMB9A and CMB9B family had the best segregation.A total of 486 microsatellite primers were evaluated using bulked segregant analysis(BSA),11 showed polymorphism between the contrasting pools and only one showed significant differences between resistant and susceptible individuals.In conclusion,fecundity was the parameter that impacted most on the intrinsic rate of A.socialis population growth. 展开更多
关键词 CASSAVA wild parents interspecific hybrids whitefly resistance BSA
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Effect of treatment failure on the Cag A EPIYA motif in Helicobacter pylori strains from Colombian subjects
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作者 Javier Andres Bustamante-Rengifo Andres Jenuer Matta +1 位作者 Alvaro Jairo Pazos Luis Eduardo Bravo 《World Journal of Gastroenterology》 SCIE CAS 2017年第11期1980-1989,共10页
AIM To evaluate effect of treatment failure on cag A and vac A genotypes in Helicobacter pylori(H. pylori) isolates from Colombia.METHODS One hundred and seventy-six participants infected with H. pylori from Colombia ... AIM To evaluate effect of treatment failure on cag A and vac A genotypes in Helicobacter pylori(H. pylori) isolates from Colombia.METHODS One hundred and seventy-six participants infected with H. pylori from Colombia were treated during 14 d with the triple-standard therapy. Six weeks later, eradication was evaluated by 13C-Urea breath test. Patients with treatment failure were subjected to endoscopy control; biopsies obtained were used for histopathology and culture. DNA from H. pylori isolates was amplified using primers specific for cag A and vac A genes. The phylogenetic relationships among isolates obtained before and after treatment were established by conglomerate analysis based on random amplified polymorphic DNA(RAPD) fingerprinting.RESULTS Treatment effectiveness was at 74.6%. Of the par-ticipants with treatment failure, 25 accepted subjected to a second endoscopy. Prevalence of posttreatment infection was 64%(16/25) and 40%(10/25) by histology and culture, respectively. Upon comparing the cag A and vac A genotypes found before and after therapy, multiple cag A genotypes(cag A-positive and cag A-negative) were found before treatment; in contrast, cag A-negative genotypes decreased after treatment. vac A s1m1 genotype was highly prevalent in patients before and after therapy. The 3'cag A region was successfully amplified in 95.5%(21/22) of the isolates obtained before and in 81.8%(18/22) of the isolates obtained after treatment. In the isolates obtained from patients with treatment failure, it was found that 72.7%(16/22) presented alterations in the number of EPIYA motifs, compared to isolates found before treatment.CONCLUSION Unsuccessful treatment limits colonization by lowvirulence strains resulting in partial and selective eradication in mixed infections, and acts on the cag A-positive strains inducing genetic rearrangements in cag A variable region that produces a loss or gain of EPIYA repetitions. 展开更多
关键词 Helicobacter pylori RAPD-PCR Treatment failure EPIYA motifs 3’ cag A variable region
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Comparative mitogenome phylogeography of two anteater genera (Tamandua and Myrmecophaga;Myrmecophagidae, Xenarthra): Evidence of discrepant evolutionary traits
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作者 Manuel Ruiz-García Daniel Pinilla-Beltrán +3 位作者 Oscar E.Murillo-García Christian Miguel Pinto Jorge Brito Joseph Mark Shostell 《Zoological Research》 SCIE CAS CSCD 2021年第5期525-547,共23页
The species within Xenarthra(sloths,anteaters,and armadillos)are quintessential South American mammals.Of the three groups,Vermilingua(anteaters)contains the fewest extant and paleontological species.Here,we sampled a... The species within Xenarthra(sloths,anteaters,and armadillos)are quintessential South American mammals.Of the three groups,Vermilingua(anteaters)contains the fewest extant and paleontological species.Here,we sampled and sequenced the entire mitochondrial genomes(mitogenomes)of two Tamandua species(Tamandua tetradactyla and T.mexicana)(n=74)from Central and South America,as well as Myrmecophaga tridactyla(n=41)from South America.Within Tamandua,we detected three different haplogroups.The oldest(THI)contained many specimens with the T.tetradactyla morphotype(but also several with the T.mexicana morphotype)and originated in southeastern South America(currently Uruguay)before moving towards northern South America,where the THII haplogroup originated.THII primarily contained specimens with the T.mexicana morphotype(but also several with the T.tetradactyla morphotype)and was distributed in Central America,Colombia,and Ecuador.THI and THII yielded a genetic distance of 4%.THII originated in either northern South America or“in situ”in Central America with haplogroup THIII,which consisted of~50%T.mexicana and 50%T.tetradactyla phenotypes.THIII was mostly located in the same areas as THII,i.e.,Central America,Ecuador,and Colombia,though mainly in the latter.The three haplogroups overlapped in Colombia and Ecuador.Thus,T.tetradactyla and T.mexicana were not reciprocally monophyletic.For this reason,we considered that a unique species of Tamandua likely exists,i.e.,T.tetradactyla.In contrast to Tamandua,M.tridactyla did not show different morphotypes throughout its geographical range in the Neotropics.However,two very divergent genetic haplogroups(MHI and MHII),with a genetic distance of~10%,were detected.The basal haplogroup,MHI,originated in northwestern South America,whereas the more geographically derived haplogroup,MHII,overlapped with MHI,but also expanded into central and southern South America.Thus,Tamandua migrated from south to north whereas Myrmecophaga migrated from north to south.Our results also showed that temporal mitochondrial diversification for Tamandua began during the Late Pliocene and Upper Pleistocene,but for Myrmecophaga began during the Late Miocene.Furthermore,both taxa showed elevated levels of mitochondrial genetic diversity.Tamandua showed more evidence of female population expansion than Myrmecophaga.Tamandua experienced population expansion~0.6–0.17 million years ago(Mya),whereas Myrmecophaga showed possible population expansion~0.3–0.2 Mya.However,both taxa experienced a conspicuous female decline in the last 10000–20000 years.Our results also showed little spatial genetic structure for both taxa.However,several analyses revealed higher spatial structure in Tamandua than in Myrmecophaga.Therefore,Tamandua and Myrmecophaga were not subjected to the same biogeographical,geological,or climatological events in shaping their genetic structures. 展开更多
关键词 Anteaters Genetic diversity Mitogenomes Myrmecophaga NEOTROPICS PHYLOGEOGRAPHY Spatial structure Tamandua
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Changes in Mangrove Epifaunal Assemblages Caused by Forest Logging during Hunting of the Neotropical Cormorant (<i>Phalacrocorax brasilianus</i>) on the Colombian Pacific Coast
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作者 Carlos Andrés Satizabal R. Jaime Ricardo Cantera Kintz Paula Cristina Sierra-Correa 《Open Journal of Marine Science》 2012年第4期150-156,共7页
Although the importance of mangroves is clearly recognized around the world, these ecosystems are being strongly altered by the logging of their forests for multiple purposes. The Colombian Pacific coast is not an exc... Although the importance of mangroves is clearly recognized around the world, these ecosystems are being strongly altered by the logging of their forests for multiple purposes. The Colombian Pacific coast is not an exception to this situation, and apart from the traditional logging of wood, the hunting of the Neotropical Cormorant or Pato-cuervo (Phalacrocorax brasilianus), an activity largely unknown but widespread in the region, is also causing the logging of great extensions of mangroves. The aim of this research was to determine if the assemblages of mollusks and crustaceans of these mangroves are being affected by the hunting of the cormorant. To answer this question, quantitative samplings were realized in four transects in logged and unlogged mangrove areas on the southwestern coast of the Colombian Pacific and diversity, equitability and dominance of macrofaunal assemblages of mangroves were calculated. The data show that although significant differences between diversity indices were not found, there were important differences in equitability (total J’: 0.55 in T1, 0.77 in T2, 0.46 in T3 and 0.65 in T4), specific dominance, and composition of species (T1: 11 species, T2: 13, T3: 9 and T4: 11) between logged and unlogged areas. Based on these results, although forest structure and interstitial salinity were different among transects, we conclude that the present practice of exploitation of the Neotropical Cormorant is affecting the epifaunal populations of mangroves, causing changes in the composition and dominance of species. 展开更多
关键词 MANGROVE Mollusks Crustaceans NEOTROPICAL CORMORANT Colombian Pacific
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Identification of Global Gene Expression Shifts Using Microarray Data from Different Biological Conditions
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作者 José Rafael Tovar Cuevas +3 位作者 Liliana Ló pez Kleine José Alejandro Ordoñ ez 《Open Journal of Statistics》 2015年第5期360-372,共13页
Gene expression data have been very useful during the past two decades for the detection of differentially expressed genes when two (or more) biological conditions are compared. Studies seeking for differentially expr... Gene expression data have been very useful during the past two decades for the detection of differentially expressed genes when two (or more) biological conditions are compared. Studies seeking for differentially expressed genes are based on testing gene by gene for a mean differential expression between two conditions. Nevertheless, the global shift in gene expression when taking into account all genes present on a microarray experiment, has not yet been investigated and could provide different information on genes that could be affected by the condition under research. Such a global approach would help identifying a gene expression threshold, characteristic of a certain condition and therefore could be used for diagnosis together with the list of differentially expressed genes detected by classical methods. Moreover, characterizing genes below or above such a threshold could give new insights into the molecular mechanisms implicated functionally in each condition. Here, we present a simple methodology, based on heuristics, gene filtering, variable transformation and descriptive statistics in order to identify such global gene expression shifts and the characteristic threshold so the same can be applied by any professional that works with expression gene data and not only by statisticians. Our procedure is illustrated on a real gene expression data set comparing pathogen inoculated tomatoes with non-inoculated tomatoes. This methodology can be used for the identification of the threshold values when we have continuous variable data sets from two populations with overlapped distributional forms (histograms) in most of their percentiles. 展开更多
关键词 Gene Expression SHIFT FILTERING Transformation THRESHOLD BIOLOGICAL CONDITIONS
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