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91.
Two New Species of Zoothamnium (Ciliophora,Peritrichia) from Korea,with New Observations of Z. parahentscheli Sun et al., 2009 下载免费PDF全文
Shahed Uddin Ahmed Shazib Ping Sun Liqiong Li Mann Kyoon Shin 《The Journal of eukaryotic microbiology》2015,62(4):505-518
Three peritrichous ciliates, Zoothamnium arcuatum n. sp., Z. grossi n. sp., and Z. parahentscheli Sun et al., 2009, were collected from an estuary of the Taehwagang River, Korea. All these species were investigated based on live observations and silver staining, and their small subunit (SSU) rRNA gene was also sequenced. Zoothamnium arcuatum can be identified by a goblet‐shaped colony, double‐layered peristomial lip, and abstomally shortened row 3 of infundibular polykinety 3 (P3). Zoothamnium grossi is morphologically characterized by an alternately branched stalk with the lowest secondary stalk diverging from the main part of colony, asymmetrically bell‐shaped zooids, and three short, parallel ciliary rows in P3. Phylogenetic analysis revealed that the three Zoothamnium species described in this paper clustered with other members of the family Zoothamniidae, as expected. 相似文献
92.
Najmul Haider Md. Shafiqur Rahman Salah Uddin Khan Andrea Mikolon Muzaffor G. Osmani Emily S. Gurley Ireen Sultana Shanta Suman Kumer Paul Laura Macfarlane-Berry Ariful Islam Ausraful Islam James Desmond Jonathan H. Epstein Rachael A. Priestley Gilbert J. Kersh Mohammed Ziaur Rahman Peter Daszak Stephen P. Luby Robert F. Massung Nord Zeidner 《EcoHealth》2015,12(2):354-358
93.
doi: 10.1111/j.1741‐2358.2011.00617.x Oral health status in elders from South Brazil: a population‐based study Objective: To assess the oral health status of community‐dwelling adults aged 60 years and older from southern Brazil and to determine demographics, socioeconomic, behavioural and dental risk indicators. Materials and methods: This cross‐sectional study used a multistage, probability sampling method to draw a representative sample of the metropolitan area of Porto Alegre, Brazil. A subsample of 217 subjects was included in this analysis. Oral mucosal lesions, dental caries, tooth loss and periodontal status (full‐mouth, six sites per tooth exam) were assessed by calibrated examiners. Results: Prevalence of edentulism was 39.5%, and mean tooth loss was 20.2 (SE = 0.6). Older individuals [Odds Ratio (OR) = 2.2], women (OR = 2.3), white people (OR = 5.9), individuals of lower socioeconomic status (OR = 5.6) and smokers (OR = 3.5) had higher likelihood of being edentulous. Approximately 36% of dentate individuals had caries and/or restoration affecting, in average, 5.0 teeth. Periodontitis affected 79% of subjects, and it was associated with older age (OR = 4.0), men (OR = 3.4) and large amounts of supragingival plaque (OR = 3.0). Conclusion: Poor oral health was observed in this elderly population from South Brazil. Sociodemographic disparities accounted for most of the burden of disease and treatment needs. 相似文献
94.
95.
Qu YY Zhou JT Wang J Xing LL Jiang N Gou M Salah Uddin M 《Bioresource technology》2009,100(1):244-248
The performances and microbial population changes in laboratory-scale membrane bioreactor (MBR) augmented with Sphingomonas xenophaga QYY were investigated in the present study. It was demonstrated that after 30 days acclimation, the non-augmented MBR system were able to degrade bromoamine acid (BAA) well. However, the efficiency of the system decreased with BAA concentration increasing. While the augmented MBR showed higher capability, in which the color and COD removal were more than 90% and 50%, respectively. By ribosomal intergenic spacer analysis (RISA), it was found that BAA-utilizing populations gradually increased to become the dominant species in the non-augmented MBR. However, the augmented MBR possessed relatively stable treatment abilities, in which the introduced strain QYY could be persistent and co-exist well with the indigenous populations. 相似文献
96.
Antioxidant defense responses: physiological plasticity in higher plants under abiotic constraints 总被引:4,自引:0,他引:4
Cheruth Abdul Jaleel Ksouri Riadh Ragupathi Gopi Paramasivam Manivannan Jallali Inès Hameed Jasim Al-Juburi Zhao Chang-Xing Shao Hong-Bo Rajaram Panneerselvam 《Acta Physiologiae Plantarum》2009,31(3):427-436
Environmental stresses (salinity, drought, heat/cold, light and other hostile conditions) may trigger in plants oxidative
stress, generating the formation of reactive oxygen species (ROS). These species are partially reduced or activated derivatives
of oxygen, comprising both free radical and non-radical (H2O2) forms, leading to cellular damage, metabolic disorders and senescence processes. In order to overcome oxidative stress,
plants have developed two main antioxidants defense mechanisms that can be classified as non-enzymatic and enzymatic systems.
The first class (non-enzymatic) consists of small molecules such as vitamin (A, C and E), glutathione, carotenoids and phenolics
that can react directly with the ROS by scavenging them. Second class is represented by enzymes among them superoxide dismutase,
peroxidase and catalase which have the capacity to eliminate superoxide and hydrogen peroxide. In this review, we have tried
to explore the related works, which have revealed the changes in the basic antioxidant metabolism of plants under various
abiotic constraints. 相似文献
97.
Rashid Uz Zaman A. S. M. Alamgir Mustafizur Rahman Eduardo Azziz-Baumgartner Emily S. Gurley M. Abu Yushuf Sharker W. Abdullah Brooks Tasnim Azim Alicia M. Fry Stephen Lindstrom Larisa V. Gubareva Xiyan Xu Rebecca J. Garten M. Jahangir Hossain Salah Uddin Khan Labib Imran Faruque Syeda Shegufta Ameer Alexander I. Klimov Mahmudur Rahman Stephen P. Luby 《PloS one》2009,4(12)
Background
Recent population-based estimates in a Dhaka low-income community suggest that influenza was prevalent among children. To explore the epidemiology and seasonality of influenza throughout the country and among all age groups, we established nationally representative hospital-based surveillance necessary to guide influenza prevention and control efforts.Methodolgy/Principal Findings
We conducted influenza-like illness and severe acute respiratory illness sentinel surveillance in 12 hospitals across Bangladesh during May 2007–December 2008. We collected specimens from 3,699 patients, 385 (10%) which were influenza positive by real time RT-PCR. Among the sample-positive patients, 192 (51%) were type A and 188 (49%) were type B. Hemagglutinin subtyping of type A viruses detected 137 (71%) A/H1 and 55 (29%) A/H3, but no A/H5 or other novel influenza strains. The frequency of influenza cases was highest among children aged under 5 years (44%), while the proportions of laboratory confirmed cases was highest among participants aged 11–15 (18%). We applied kriging, a geo-statistical technique, to explore the spatial and temporal spread of influenza and found that, during 2008, influenza was first identified in large port cities and then gradually spread to other parts of the country. We identified a distinct influenza peak during the rainy season (May–September).Conclusions/Significance
Our surveillance data confirms that influenza is prevalent throughout Bangladesh, affecting a wide range of ages and causing considerable morbidity and hospital care. A unimodal influenza seasonality may allow Bangladesh to time annual influenza prevention messages and vaccination campaigns to reduce the national influenza burden. To scale-up such national interventions, we need to quantify the national rates of influenza and the economic burden associated with this disease through further studies. 相似文献98.
James G. Biddlecombe Graeme Smith Shahid Uddin Sandrine Mulot David Spencer Chris Gee Brendan C. Fish Daniel G. Bracewell 《Biotechnology progress》2009,25(5):1499-1507
A rotating disk shear device was used to study the effect of interfacial shear on the structural integrity of human monoclonal antibodies of IgG4 isotype. Factors associated with the solution conditions (pH, ionic strength, surfactant concentration, temperature) and the interface (surface roughness) were studied for their effect on the rate of IgG4 monomer loss under high shear conditions. The structural integrity of the IgG4 was probed after exposure to interfacial shear effects by SDS‐PAGE, IEF, dynamic light scattering, and peptide mapping by LC‐MS. This analysis revealed that the main denaturation pathway of IgG4 exposed to these effects was the formation of large insoluble aggregates. Soluble aggregation, breakdown in primary structure, and chemical modifications were not detected. The dominant factors found to affect the rate of IgG4 monomer loss under interfacial shear conditions were found to be pH and the nanometer‐scale surface roughness associated with the solid‐liquid interface. Interestingly, temperature was not found to be a significant factor in the range tested (15–45°C). The addition of surfactant was found to have a significant stabilizing effect at concentrations up to 0.02% (w/v). Implications of these findings for the bioprocessing of this class of therapeutic protein are briefly discussed. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 相似文献
99.
Four labdane alkaloids, haterumaimides N-Q (1-4), were isolated from an ascidian Lissoclinum sp. and their structures were elucidated by chemical and spectral analyses. Investigation of the structure-activity relationships of haterumaimides J-K, N-Q, and 14 related compounds suggested that the presence of hydroxyl groups at C-6, C-7, C-12, and C-18, a chlorine atom at C-2, and an imido NH in ring C should be essential for cytotoxicity against P388 cells. 相似文献
100.
Samreen Kazi J. Shultz J. Afzal Rizwan Hashmi Mohammed Jasim Jason Bond Prakash R. Arelli David A. Lightfoot 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,120(3):633-644
Soybean [Glycine max (L.) Merr.] cultivars varied in their resistance to different populations of the soybean cyst nematode (SCN), Heterodera glycines, called HG Types. The rhg1 locus on linkage group G was necessary for resistance to all HG types. However, the loci for resistance to H. glycines HG Type 1.3- (race 14) and HG Type 1.2.5- (race 2) of the soybean cyst nematode have varied in their reported locations.
The aims were to compare the inheritance of resistance to three nematode HG Types in a population segregating for resistance
to SCN and to identify the underlying quantitative trait loci (QTL). ‘Hartwig’, a soybean cultivar resistant to most SCN HG
Types, was crossed with the susceptible cultivar ‘Flyer’. A total of 92 F5-derived recombinant inbred lines (RILs; or inbred
lines) and 144 molecular markers were used for map development. The rhg1 associated QTL found in earlier studies were confirmed and shown to underlie resistance to all three HG Types in RILs (Satt309;
HG Type 0, P = 0.0001 R
2 = 22%; Satt275; HG Type 1.3, P = 0.001, R
2 = 14%) and near isogeneic lines (NILs; or iso-lines; Satt309; HG Type 1.2.5-, P = 0.001 R
2 = 24%). A new QTL underlying resistance to HG Type 1.2.5- was detected on LG D2 (Satt574; P = 0.001, R
2 = 11%) among 14 RILs resistant to the other HG types. The locus was confirmed in a small NIL population consisting of 60
plants of ten genotypes (P = 0.04). This QTL (cqSCN-005) is located in an interval previously associated with resistance to both SDS leaf scorch from
‘Pyramid’ and ‘Ripley’ (cqSDS-001) and SCN HG Type 1.3- from Hartwig and Pyramid. The QTL detected will allow marker assisted
selection for multigenic resistance to complex nematode populations in combination with sudden death syndrome resistance (SDS)
and other agronomic traits. 相似文献