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| 1 | Phylogenetic alpha and beta diversity in tropical tree assemblages along regionalscale environmental gradients in northwest South America显示文摘Aims Environmental gradients are drivers of species diversity;however,we know relatively little about the evolutionary processes underlying these relationships.A potentially powerful approach to studying diversity gradients is to quantify the phylogenetic structure within and between assemblages arrayed along broad spatial and environmental gradients.Here,we evaluate the phylogenetic structure of plant assemblages along an environmental gradient with the expectation that the habitat specialization of entire lineages is an important evolutionary pattern influencing the structure of tree communities along environmental gradients.Methods We evaluated the effect of several environmental variables on the phylogenetic structure of plant assemblages in 145 plots distributed in northwestern South America that cover a broad environmental gradient.The phylogenetic alpha diversity was quantified for each plot and the phylogenetic beta diversity between each pair of plots was also quantified.Both the alpha and beta diversity measures were then related to spatial and environmental gradients in the study system.Important Findings We found that gradients in temperature and potential evapotranspiration have a strong relationship with the phylogenetic alpha diversity in our study system,with phylogenetic overdispersion in low temperatures and phylogenetic clustering at higher temperatures.Further,the phylogenetic beta diversity between two plots increases with an increasing difference in temperature,whereas annual precipitation was not a significant predictor of community phylogenetic turnover.We also found that the phylogenetic structure of the plots in our study system was related to the degree of seasonal flooding and seasonality in precipitation.In particular,more stressful environments such as dry forests and flooded forests showed phylogenetic clustering.Finally,in contrast with previous studies,we find that phylogenetic beta diversity was not strongly related to the spatial distance separating two forest plots,which may be the result of the importance of the three independent mountain ranges in our study system,which generate a high degree of environmental variation over very short distances.In conclusion,we found that environmental gradients are important drivers of both phylogenetic alpha and phylogenetic beta diversities in these forests over spatial distance. | Sebastián González-Caro María Natalia Umaña Esteban Álvarez Pablo R.Stevenson Nathan G.Swenson | 2014 | Journal of Plant Ecology2014，7，2： | 17 |
| 2 | Prognostic factors for recurrence of gastrointestinal bleeding due to Dieulafoy's lesion显示文摘AIM:To analyze the effectiveness of the endoscopic therapy and to identify prognostic factors for recurrent bleeding.METHODS:Retrospective study of patients with gastrointestinal bleeding secondary to Dieulafoy's lesion(DL) from 2005 to 2011.We analyzed the demographic characteristics of the patients,risk factors for gastrointestinal bleeding,endoscopic findings,characteristics of the endoscopic treatment,and the recurrence of bleeding.We included cases in which endoscopy described a lesion compatible with Dieulafoy.We excluded patients who had potentially bleeding lesions such as angiodysplasia in other areas or had undergone other gastrointestinal endoscopic procedures.RESULTS:Twenty-nine patients with DL were identified.Most of them were men with an average age of 71.5 years.Fifty-five percent of the patients received antiaggregatory or anticoagulant therapy.The most common location for DL was the stomach(51.7%).The main type of bleeding was oozing in 65.5% of cases.In 27.6% of cases,there was arterial(spurting) bleeding,and 6.9% of the patients presented with an adherent clot.A single endoscopic treatment was applied to nine patients(31%);eight of them with adrenaline and one with argon,while 69% of the patients received combined treatment.Six patients(20.7%) presented with recurrent bleeding at a median of 4 d after endoscopy(interquartile range = 97.75).Within these six patients,the new endoscopic treatment obtained a therapeutic success of 100%.The presence of arterial bleeding at endoscopy was associated with a higher recurrence rate for bleeding(50% vs 33.3% for other type of bleeding) [P = 0.024,odds ratio(OR) = 8.5,95% CI = 1.13-63.87].The use of combined endoscopic treatment prevented the recurrence of bleeding(10% vs 44.4% of single treatment)(P = 0.034,OR = 0.14,95% CI = 0.19-0.99).CONCLUSION:Endoscopic treatment of DL is safe and effective.Adrenaline monotherapy and arterial(spurting) bleeding are associated with a high rate of bleeding recurrence. | Yuliana Jamanca-Poma Antonio Velasco-Guardado Concepción Piero-Pérez Renzo Calderón-Begazo Josue Umaa-Mejía Fernando Geijo-Martínez Antonio Rodríguez-Pérez | 2012 | World Journal of Gastroenterology2012，18，40： | 11 |
| 3 | Association of endothelial nitric oxide synthase gene T-786C promoter polymorphism with gastric cancer显示文摘AIM: To investigate the role of endothelial nitric oxide synthase-786 T > C promoter polymorphism in the etiology of gastric cancer(GC). METHODS: A total of 150 GC patients and 150 control subjects were included in the study. The information on demographic features was elicited with an informed consent from all the patients and control subjects using a structured questionnaire. Helicobacter pylori(H. pylori) infectivity status was tested in antral biopsies from all the subjects by rapid urease test following the method of Vaira et al. Genomic DNA was isolated from whole blood samples following the salting out method of Lahiri et al. Genotype analysis of the rs2070744 polymorphism was carried out by allele-specific polymerase chain reaction method. The genotypes were determined based on the appearance of bands on an agarose gel stained with ethidium bromide under ultraviolet gel documentation with the help of 100 bp ladder. Odds ratios and corresponding 95%CIs were determined using java stat online software. RESULTS: There was a significant difference in the distribution of C allele(C vs T; P = 0.000, OR = 5.038) in patient group compared to the control subjects exhibiting a fivefold increased risk for GC. When the T/T and C/C genotypes were compared, there was an enhanced GC risk for individuals with C/C genotype(T/T vs C/C; P = 0.000). Among the demographic factors, smoking and alcoholism were the common risk factors in patients compared to the control subjects(P < 0.05). Patients with smoking and alcoholism developed cancer even in heterozygous T/C condition(smoking: P = 0.020 and alcoholism: P = 0.005). Individuals with H. pylori infection showed seven fold increased risk for cancer. All the patients with C/C genotype revealed a significant association between H. pylori infection and GC. Among the patients 2.4% of them revealed familial incidence of GC. No significant difference was noticed between cases and controls with regard to consanguinity(P = 0.473).CONCLUSION: The Present data suggest that eN OS-786 C/C genotype and C allele may be considered as potential risk factors in patients with GC. | Devulapalli Krishnaveni Bhayal Amar Chand Porika Shravan Kumar Malladi Uma Devi Macherla Ramanna Akka Jyothy Nallari Pratibha N Balakrishna Ananthapur Venkateshwari | 2015 | World Journal of Gastrointestinal Oncology2015，7，7： | 2 |
| 4 | Protection against radiation-induced chromosome damage in mouse bone marrow by Ocimum sanctum显示文摘 | GANASOUNDARI A UMA DEVI P RAO M N A | 1997 | Mutation Research1997，373，： | 1 |
| 5 | Long-term effects of diagnostic ultrasound during fetal period on postnatal development and adult behavior of mouse显示文摘 | Suresh R Uma Devi P Ovchinnikov N | 2002 | Life Sci2002，71，3： | 1 |
| 6 | Fly ash for the removal of Mn(II) from aqueous solutions and wastewaters显示文摘 | SHARMA Y C UMA SINGH S N | 2007 | Chemical Engineering Journal2007，132，： | 1 |
| 7 | Fly ash for the removal of Mn( II ) from aqueous solutions and waste- waters 显示文摘 | Sharma Y C Uma Singh S N | 2007 | Chem Eng J2007，132，1： | 1 |
| 8 | Antimicrobial activity of Some Ganoderma species from nigeria 显示文摘 | Ofodile L N Uma N U Kokubum T | 2005 | Phytother Res2005，19，： | 1 |
| 9 | AgBr/ Al-MCM-41 visible-light photocatalyst for gas-phase de- composition of CH3CHO 显示文摘 | RODRIGUES S UMA S MARTYANOV I N | 2005 | J Catal2005，233，2： | 1 |
| 10 | Altered cardiac tissue and plasma kininogen levels in hypertensive and diabetic rats 显示文摘 | SHARMA J N UMA K YUSOF A P | 1999 | Immunopharmacology1999，34，： | 1 |
| 11 | Me- tastasis of squamous cell carcinoma of the oral tongue is associated with downregulation of epidermal fatty acid binding protein (E-FABP)显示文摘 | UMA R S NARESH K N DfCRUZ A K | 2007 | Oral Oncol2007，43，： | 1 |
| 12 | Removal of a cationic dye from wastewaters by adsorption on activated carbon devel- oped from coconut coir显示文摘 | SHARMA Y C UMA UPADHYAY S N | 2009 | Energy & Fuels2009，23，： | 1 |
| 13 | Protection a- gainst radiation-induced chromosome damage in mouse bone marrow by Oclrnum sancyum显示文摘 | Canasoundari A Uma Devi P Rao M N A | 1997 | Mutation Research1997，373，： | 1 |
| 14 | An economicallyviable removal of methylene blue by adsorption onactivated carbon prepared from rice husk显示文摘 | Sharma Y C Uma Upadhyay S N | 2011 | CanadianJournal of Chemical Engineering2011，89，2： | 1 |
| 15 | Persistently high venous-to-arterial carbon dioxide differences during early resuscitation are associated with poor outcomes in septic shock显示文摘 | Ospina-Tascón GA Bautista-Rincón DF Uma(n)a M | 2013 | Crit Care2013，17，： | 1 |
| 16 | To termination or not an ongoing R&D project:a management dilemma 显示文摘 | VINED K ADITHA N S UMA K | 1996 | IEEE Transactions on Engineering Management1996，43，3： | 1 |
| 17 | Long-term effects of diagnostic ultrasound during fetal period on postnatal development and adult behavior of mouse显示文摘 | Suresh R Uma Devi P Ovchinnikov N | 2002 | Life Sci2002，71，： | 1 |
| 18 | Synthesis of zeolites from coal fly ash: an overview显示文摘 | X Querol N Moreno J.C Uma?a A Alastuey E Hernández A López-Soler F Plana | 2002 | International Journal of Coal Geology2002，，1： | 1 |
| 19 | Antimicrobial activity of Some Ganoderma species from Nigeria显示文摘 | Ofodile L N Uma N U Kokubum T | | 0，，： | 1 |
| 20 | Association of seven func-tional polymorphisms of one-carbon metabolic pathway with totalplasma homocysteine levels and susceptibility to Parkinson's dis-ease among South Indians 显示文摘 | Kumudini N Uma A Naushad SM | 2014 | Neurosci Lett2014，568，： | 1 |
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