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2.
QJM ; 110(3): 195-196, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28069907
3.
Int J Oral Maxillofac Surg ; 46(4): 407-412, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27919662

RESUMO

The incidence of squamous cell carcinoma (SCC) of the tongue accounts for 90% of all malignancies affecting the oral cavity and oropharynx. The distribution between the anterior and posterior tongue is equal. Nodal metastasis is dependent on various factors including tumour thickness, site, size, differentiation, and perineural and perivascular invasion. There is increasing evidence of a close correlation between tumour thickness and metastasis. A retrospective study covering the 16-year period from 2000 to 2016 was performed. Eighty-one patients with anterior tongue SCC were included. The only primary treatment was surgery. All patients were T1/T2N0M0 stage. Sixty-five patients underwent local excision with simultaneous selective neck dissection; 29 of these patients were confirmed to have occult metastasis. Sixteen patients underwent local excision only as an initial treatment. Four of them subsequently developed neck metastasis within a 6- to 18-month period. The results of this study support recent publications associating tumour thickness with nodal disease. Therefore, it is postulated that prophylactic neck dissection should be considered when the tumour thickness of anterior tongue SCC exceeds 5mm, in order to prevent lymphatic spread and improve the survival rate.


Assuntos
Carcinoma de Células Escamosas/patologia , Metástase Linfática/patologia , Neoplasias da Língua/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/cirurgia , Feminino , Glossectomia , Humanos , Excisão de Linfonodo , Masculino , Pessoa de Meia-Idade , Esvaziamento Cervical , Gradação de Tumores , Estadiamento de Neoplasias , Estudos Retrospectivos , Neoplasias da Língua/cirurgia , Resultado do Tratamento
4.
J Environ Manage ; 167: 167-74, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26686069

RESUMO

Excessive phosphate in wastewater should be removed to control eutrophication of water bodies. The potential of employing amorphous zirconium (Zr) hydroxide to remove phosphate from synthetic wastewater was studied in batch adsorption experiments and in a submerged membrane filtration adsorption hybrid (MFAH) reactor. The adsorption data satisfactorily fitted to Langmuir, pseudo-first order and pseudo-second order models. Langmuir adsorption maxima at 22 °C and pHs of 4.0, 7.1, and 10.0 were 30.40, 18.50, and 19.60 mg P/g, respectively. At pH 7.1 and temperatures of 40 °C and 60 °C, they were 43.80 and 54.60 mg P/g, respectively. The thermodynamic parameters, ΔG° and ΔS° were negative and ΔH° was positive. FTIR, zeta potential and competitive phosphate, sulphate and nitrate adsorption data showed that the mechanism of phosphate adsorption was inner-sphere complexation. In the submerged MFAH reactor experiment, when Zr hydroxide was added at doses of 1-5 g/L once only at the start of the experiment, the removal of phosphate from 3 L of wastewater containing 10 mg P/L declined after 5 h of operation. However, when Zr hydroxide was repeatedly added at 5 g/L dose every 24 h, satisfactory removal of phosphate was maintained for 3 days.


Assuntos
Hidróxidos/química , Fosfatos/química , Eliminação de Resíduos Líquidos/instrumentação , Águas Residuárias/química , Zircônio/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Nitratos/química , Fosfatos/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier , Sulfatos/química , Temperatura , Termodinâmica , Eliminação de Resíduos Líquidos/métodos
6.
J Hazard Mater ; 287: 306-16, 2015 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-25668299

RESUMO

Heavy metals are serious pollutants in aquatic environments. A study was undertaken to remove Cu, Cd, Ni, Pb and Zn individually (single metal system) and together (mixed metals system) from water by adsorption onto a sodium titanate nanofibrous material. Langmuir adsorption capacities (mg/g) at 10(-3)M NaNO3 ionic strength in the single metal system were 60, 83, 115 and 149 for Ni, Zn, Cu, and Cd, respectively, at pH 6.5 and 250 for Pb at pH 4.0. In the mixed metals system they decreased at high metals concentrations. In column experiments with 4% titanate material and 96% granular activated carbon (w/w) mixture at pH 5.0, the metals breakthrough times and adsorption capacities (for both single and mixed metals systems) decreased in the order Pb>Cd, Cu>Zn>Ni within 266 bed volumes. The amounts adsorbed were up to 82 times higher depending on the metal in the granular activated carbon+titanate column than in the granular activated carbon column. The study showed that the titanate material has high potential for removing heavy metals from polluted water when used with granular activated carbon at a very low proportion in fixed-bed columns.


Assuntos
Carbono/química , Metais Pesados/química , Nanofibras/química , Óxidos/química , Titânio/química , Poluentes Químicos da Água/química , Adsorção , Purificação da Água/métodos , Madeira
7.
J Neonatal Perinatal Med ; 7(1): 75-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24815709

RESUMO

BACKGROUND: Persistent urogenital sinus is one of the rare urogenital anomalies, which commonly presents as hydrometrocolpos. Fetal urinary ascites as a presentation of persistent urogenital sinus is extremely rare. CASE REPORT: We report on a preterm infant with antenatal diagnosis of hydrometrocolpos and massive urinary ascites secondary to urogenital sinus without any bladder or renal abnormalities. CONCLUSION: This case report emphasizes the importance of maintaining a high index of suspicion in the diagnosis of persistent urogenital sinus especially in infants presenting with urinary ascites along with hydrometrocolpos.


Assuntos
Ascite/urina , Colpotomia/métodos , Hidrocolpos/diagnóstico por imagem , Anormalidades Urogenitais/diagnóstico por imagem , Vagina/diagnóstico por imagem , Fístula Vesicovaginal/diagnóstico por imagem , Adulto , Ascite/congênito , Ascite/diagnóstico por imagem , Feminino , Humanos , Hidrocolpos/congênito , Hidrocolpos/embriologia , Recém-Nascido , Gravidez , Ultrassonografia Pré-Natal , Anormalidades Urogenitais/embriologia , Anormalidades Urogenitais/cirurgia , Vagina/anormalidades , Vagina/cirurgia , Fístula Vesicovaginal/congênito , Fístula Vesicovaginal/cirurgia
9.
N Z Vet J ; 56(3): 115-9, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18536770

RESUMO

AIM: To determine the concentration of fluoride (F) in the metacarpi from ewes of varying age, which had been grazing pastures that had been regularly topdressed with phosphatic fertilisers, which contain F as a contaminant, for at least 30 years. METHODS: Three groups of 10 ewes aged 6-8, 18-20 and 60-72 months were selected from seven research farms with a known fertiliser history, representing the major sheep farming regions of New Zealand. Lambs were born and remained on the property. The sheep were collected and slaughtered in autumn, and the right metacarpus removed for determination of F content. Representative samples of topsoil (0-30- and 30-60-mm depths) were also collected for determination of F content. RESULTS: The total concentration of F in topsoil on the farms ranged from 161 to 712 mg/kg. The overall mean concentrations of F in metacarpi from 6-8-, 18-20- and 60-72-monthold ewes were 170 (SE 9.9), 308 (SE 13.9) and 480 (SE 28.4) mg/kg dry matter (DM), respectively. On six farms, lambs which had been exposed to limited or no ingestion of soil had the lowest concentration of F in their metacarpi. Generally, there was a curvilinear relationship between age and concentration of F in the metacarpi of sheep. On the seventh farm, the concentrations of F in the metacarpi from the 6-8- and 18-20-month-old sheep were similar but lower than those of the 60-72-month-old ewes. The area of soils on the farm where the 6-8-month-old-sheep were grazing had higher total concentrations of F in topsoil (271 mg/kg) than those soils grazed by the 18-20-month-old sheep (205 mg/kg), and this may be one reason for the elevated concentration of F in the metacarpi of the younger ewes. The concentrations of F in metacarpi, at any age, were not related to the concentration of F in topsoils. CONCLUSIONS: Many factors can influence the amounts of F in soil ingested by grazing sheep and the concentration of F in their bone. The concentration of F in the metacarpi of ewes generally increased curvilinearly with age, and the rate of accumulation of F in bone was greatest in young sheep. The potential risk of chronic fluorosis occurring in sheep grazing pastures in New Zealand is low for animals managed in a manner similar to the flocks studied, given the highest mean concentration of F was 601 mg/kg DM, observed in metacarpi from 60-72-month-old ewes, and that a concentration of at least 2,400 mg/kg DM is the threshold for chronic fluorosis.


Assuntos
Ração Animal , Criação de Animais Domésticos , Fertilizantes , Fluoretos/metabolismo , Metacarpo/metabolismo , Poluentes do Solo/metabolismo , Matadouros , Animais , Feminino , Fluoretos/química , Nova Zelândia , Ovinos , Solo/análise , Poluentes do Solo/química
10.
N Z Vet J ; 55(2): 77-80, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17410214

RESUMO

AIM: To determine the changes in concentrations of fluorine (F) in serum and bone of young sheep given a high intake of F, as F in soil, followed by a low intake of F, to simulate the varying intakes experienced by grazing sheep. METHODS: Sixty autumn-born, weaned, mixed-sex lambs were randomly divided into two groups (n=30). One group (Control) was fed a low-F (12 mg/kg dry matter; DM) lucerne/ grain diet for 345 days, while the other group (High soil-F) was fed a high-F (224 mg/kg DM) lucerne/grain diet containing 10% soil for 94 days and then a low-F diet for a further 251 days. Blood samples were collected on Days 1, 32, 94, 108, 153, 214, 280 and 345, to determine concentrations of F in serum. Groups of five or six animals from each group were killed on Days 1, 94, 153, 214, 280 and 345, to collect radii and humeri for determination of F content. The sheep were weighed at about 6-8-weekly intervals. RESULTS: Initial liveweight of the sheep was 22.1 (standard error (SE) 1.12) kg and the mean liveweight gains were 270 (SE 22.1) and 170 (SE 12.4) g/day from Days 1 to 94 and 95 to 330, respectively. The mean initial (Day 1) concentration of F in serum was 0.03 (SE 0.005) mg/L, and this changed very little for animals on the low-F diet. In sheep on the high soil-F diet, the concentration of F in serum reached 0.38 (SE 0.021) mg/L at Day 94 but after being placed on the low-F diet concentrations decreased to 0.04 (SE 0.006) mg/L after 14 days (Day 108) and then remained at about this low level for the remainder of the duration of the study. The mean concentrations of F in the humerus and radius of the lambs at Day 1 were 161 (SE 19.4) and 159 (SE 20.4) mg/kg DM, respectively, which increased to 2,784 (SE 80.6) and 1,805 (SE 51.5) mg/kg DM, respectively, at Day 94 in lambs fed the high soil-F diet, then decreased to 1,075 (SE 58.1) and 1,064 (SE 61.6) mg/kg DM at Day 153, and then progressively increased to 1,669 (SE 57.7) and 1,312 (SE 30.8) mg/kg DM at Day 345. CONCLUSIONS: The ingestion of F in soil by sheep markedly increased their concentrations of F in serum and bone, but when the soil was removed and they were fed a low-F diet, concentrations of F in serum decreased to baseline levels within 14 days while concentrations in the bone only decreased to 60-70% of the peak concentration, indicating that some of the F in bone was remobilised.


Assuntos
Criação de Animais Domésticos , Dieta , Flúor/farmacologia , Solo , Animais , Animais Recém-Nascidos , Osso e Ossos/química , Osso e Ossos/efeitos dos fármacos , Feminino , Flúor/sangue , Masculino , Estações do Ano , Ovinos , Resultado do Tratamento
11.
Environ Pollut ; 145(3): 778-86, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16831500

RESUMO

A greenhouse study was conducted to determine if concentrations of fluoride (F), which would be added to acid soils via P fertilisers, were detrimental to barley root growth. Increasing rates of F additions to soil significantly increased the soil solution concentrations of aluminium (Al) and F irrespective of the initial adjusted soil pH, which ranged from 4.25 to 5.48. High rates of F addition severely restricted root growth; the effect was more pronounced in the strongly acidic soil. Speciation calculations demonstrated that increasing rates of F additions substantially increased the concentrations of Al-F complexes in the soil. Stepwise regression analysis showed that it was the combination of the activities of AlF2(1+) and AlF(2+) complexes that primarily controlled barley root growth. The results suggested that continuous input of F to soils, and increased soil acidification, may become an F risk issue in the future.


Assuntos
Alumínio/análise , Fertilizantes/toxicidade , Fluoretos/farmacologia , Hordeum/crescimento & desenvolvimento , Poluentes do Solo/farmacologia , Alumínio/toxicidade , Compostos de Alumínio/análise , Cálcio/deficiência , Fluoretos/análise , Fluoretos/toxicidade , Hordeum/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Fósforo/toxicidade , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Solo/análise , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
12.
Anat Embryol (Berl) ; 211 Suppl 1: 87-93, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17024298

RESUMO

In vertebrates, BMPs (bone morphogenic proteins) play critical roles in establishing the basic embryonic body plan and are involved in the development of a large variety of organs and tissues. Here, we analyzed the expression pattern of various BMPs (2, 4, 5 and 7) by whole mount in situ hybridization during chick limb development. In limb, expression of BMPs suggests evolutionary conserved mechanisms of BMP-dependent differentiation between lower and higher vertebrates. During the early developmental stages, BMP-2 and BMP-7 are expressed in the posterior distal mesenchyme leaving a less prominent expression anteriorly. BMP-4 is initially expressed in the anterior mesenchyme and spreads later to the whole mesenchyme leaving a stronger expression at the anterior side. From HH-stage 25, expression of BMP-4 is observed in the anterior-posterior margins of the limb bud. The BMPs 2, 4 and 7 are expressed strongly in the AER, whereas BMP-5 is expressed as a weak signal in the distal mesoderm during the early stages of limb development. Later from HH-stage 25 onwards, BMP-5 is expressed in the dorsal and ventral muscular mass of the developing limb. As digits become identifiable, expression of BMPs are observed in the interdigital mesenchyme and can also be detected along the contours of the developing phalanges and at the distal tips of the digits. All these BMPs are found to be expressed in the developing feather buds from day 8 onwards.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Extremidades/embriologia , Perfilação da Expressão Gênica , Morfogênese/fisiologia , Animais , Embrião de Galinha , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Hibridização In Situ , Transdução de Sinais/fisiologia
13.
Anc Sci Life ; 25(3-4): 6-9, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22557199

RESUMO

The antimicrobial activity of aqueous extract leaf and stem of Santalum album was performed against Escherichia coli, Staphylococcus aureus and Pseudomonas. S. album leaf extract showed inhibition to E.coli (0.8mm), Staphylococcus aureus (1.0mm) and Pseudomonas (1.4mm) were as stem extract showed inhibition on E.coli (0.6mm), Staphylococcus aureus (0.4mm) and seudomonas (1.0mm) respectively. However leaf extract showed significantly higher inhibition when compared to stem extract. This might be due to presence of higher amount of secondary metabolites in the aqueous leaf extract.

14.
Int J Syst Evol Microbiol ; 54(Pt 4): 1185-1190, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15280289

RESUMO

A novel species, Swaminathania salitolerans gen. nov., sp. nov., was isolated from the rhizosphere, roots and stems of salt-tolerant, mangrove-associated wild rice (Porteresia coarctata Tateoka) using nitrogen-free, semi-solid LGI medium at pH 5.5. Strains were Gram-negative, rod-shaped and motile with peritrichous flagella. The strains grew well in the presence of 0.35% acetic acid, 3% NaCl and 1% KNO3, and produced acid from l-arabinose, d-glucose, glycerol, ethanol, d-mannose, d-galactose and sorbitol. They oxidized ethanol and grew well on mannitol and glutamate agar. The fatty acids 18 : 1omega7c/omega9t/omega12t and 19 : 0cyclo omega8c constituted 30.41 and 11.80% total fatty acids, respectively, whereas 13 : 1 AT 12-13 was found at 0.53%. DNA G+C content was 57.6-59.9 mol% and the major quinone was Q-10. Phylogenetic analysis based on 16S rRNA gene sequences showed that these strains were related to the genera Acidomonas, Asaia, Acetobacter, Gluconacetobacter, Gluconobacter and Kozakia in the Acetobacteraceae. Isolates were able to fix nitrogen and solubilized phosphate in the presence of NaCl. Based on overall analysis of the tests and comparison with the characteristics of members of the Acetobacteraceae, a novel genus and species is proposed for these isolates, Swaminathania salitolerans gen. nov., sp. nov. The type strain is PA51T (=LMG 21291T=MTCC 3852T).


Assuntos
Acetobacteraceae/classificação , Acetobacteraceae/isolamento & purificação , Poaceae/microbiologia , Ácido Acético/farmacologia , Acetobacteraceae/citologia , Acetobacteraceae/fisiologia , Composição de Bases , Metabolismo dos Carboidratos , Meios de Cultura/química , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , DNA Ribossômico/química , Etanol/metabolismo , Ácidos Graxos/análise , Ácidos Graxos/isolamento & purificação , Flagelos , Genes de RNAr , Violeta Genciana , Ácido Glutâmico/metabolismo , Inibidores do Crescimento/farmacologia , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Movimento , Nitratos/farmacologia , Fenazinas , Filogenia , Raízes de Plantas/microbiologia , Caules de Planta/microbiologia , Compostos de Potássio/farmacologia , Quinonas/análise , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Homologia de Sequência , Cloreto de Sódio/farmacologia
15.
Anat Embryol (Berl) ; 208(3): 219-24, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15156402

RESUMO

The growth and maintenance of the blood and lymphatic vascular systems is to a large extent controlled by members of the vascular endothelial growth factor (VEGF) family via the tyrosine kinase receptors (VEGFRs) expressed in angioblastic cells. Here, we analyzed the Quek1 (VEGFR-2) expression pattern by whole mount in situ hybridization during quail development. During early embryogenesis, Quek1 expression was detected at the caudal end of the blastoderm and primitive streak and in the head paraxial mesoderm. In somites, expression was observed from HH-stage 9 onwards in the dorsolateral region of both the forming and recently formed somites. During somite maturation, expression persists in the lateral portion of the somitic compartments, the dermomyotome and the sclerotome. Additionally, a second expression domain in the maturing somite was observed in the medial part of the sclerotome adjacent to the neural tube. This expression domain extended medially and dorsally and surrounded the neural tube during later stages. In the notochord, expression was observed from HH-stage 23 onwards. In the limb bud, expression was initiated in the mesenchyme at HH-stage 17. During organogenesis, expression was detected in the pharyngeal arches and in the anlagen of the esophagus, trachea, stomach, lungs, liver, heart and gut. Expression was also seen in feather buds from day 7 onwards. Our results confirm the angiogenic potential of the mesoderm and suggest that VEGFR-2 expressing cells represent multiple pools of mesodermal precursors of the hematopoietic and angiopoietic lineages.


Assuntos
Coturnix , Embrião não Mamífero/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Coturnix/embriologia , Embrião não Mamífero/embriologia , Desenvolvimento Embrionário/fisiologia , Desenvolvimento Fetal/fisiologia , Hibridização In Situ , Mesoderma/metabolismo , Organogênese/fisiologia , Somitos/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética
16.
Biotechnol Lett ; 25(6): 497-501, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12882278

RESUMO

A novel salt-tolerant, N2-fixing and phosphate-solubilizing, Gluconacetobacter sp. (PA12) tagged with gusA gene, colonized Porteresia coarctata (wild rice) and Pokkali (salt-tolerant variety) more intensively when compared to Ponni (salt-sensitive variety). This was confirmed using a colony-counting method.


Assuntos
Acetobacteraceae/citologia , Acetobacteraceae/crescimento & desenvolvimento , Oryza/citologia , Oryza/microbiologia , Acetobacteraceae/classificação , Acetobacteraceae/fisiologia , Contagem de Células/métodos , Divisão Celular/fisiologia , Oryza/classificação , Raízes de Plantas/classificação , Raízes de Plantas/citologia , Raízes de Plantas/microbiologia , Especificidade da Espécie
17.
Environ Pollut ; 115(2): 275-82, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11706800

RESUMO

Ingestion of soils with high fluoride (F) concentration may cause chronic fluorosis in grazing animals. Analysis of New Zealand pasture soils with long-term phosphorus (P) fertilisation histories showed that total surface soil (0-75 mm depth) F concentration increased up to 217-454 mg kg-1 with P fertiliser application. One-third to two-thirds of F applied in fertilisers resides in the top 75 mm soil depth. Pasture forage accumulation of F was low, and therefore, F intake by grazing animals through pasture consumption is expected to be much lower than F intake by soil ingestion. Ten annual applications of single superphosphate (30 and 60 kg P ha-1 year-1) to a Pallic Soil (Aeric Fragiaqualf) significantly increased total F and labile F (0.01 M CaCl2 extract) concentrations to 200 and 120 mm depths, respectively, of the 300 mm depth investigated. The mobility of F in the soil profile was similar to two other elements, P and cadmium derived from the fertiliser.


Assuntos
Cádmio/análise , Fluoretos/análise , Fósforo/análise , Plantas/química , Solo/análise , Agricultura , Animais , Fertilizantes , Concentração de Íons de Hidrogênio , Modelos Biológicos , Nova Zelândia , Fósforo/administração & dosagem
18.
J Appl Microbiol ; 91(4): 742-9, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11576312

RESUMO

AIMS: To study the diversity of the Pseudomonas populations isolated from three different plant rhizospheres, namely pearl millet, cotton and paddy, grown in saline soils along the coastline of Southern India. METHODS AND RESULTS: The Pseudomonas populations were analysed for their biochemical characters and genetic diversity using molecular tools including RAPD and PCR-RFLP. The biochemical characterization, antibiotic resistance assay and RAPD profiles revealed a largely homogeneous population. Even in PCR-RFLP restriction studies, only two groups of isolates were seen. One group was predominant in all three rhizospheres, while the other minor group consisted of salt-sensitive isolates restricted to the paddy rhizosphere alone. CONCLUSIONS: It was observed that increasing salinity caused a predominant selection of salt-tolerant species, in particular Ps. pseudoalcaligenes and Ps. alcaligenes, irrespective of the host rhizosphere. SIGNIFICANCE AND IMPACT OF THE STUDY: This study has reinstated the importance of the soil over the host plant with regard to rhizosphere populations. It has also resulted in the isolation of several salt-tolerant Pseudomonas strains, which are being screened for their biological control activity against common plant pathogens of the coastal agri-ecosystem.


Assuntos
Variação Genética , Raízes de Plantas/microbiologia , Pseudomonas/classificação , Pseudomonas/genética , Microbiologia do Solo , DNA Ribossômico/análise , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Pseudomonas/efeitos dos fármacos , Pseudomonas/isolamento & purificação , RNA Ribossômico 16S/genética , Cloreto de Sódio/farmacologia
19.
Can J Microbiol ; 47(2): 118-22, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11261490

RESUMO

Rhizobia are used exclusively in agricultural systems for enhancing the ability of legumes to fix atmospheric nitrogen. Knowledge about the indigenous population is necessary for the selection and application of inoculant strains. In this study, we have assessed the genetic diversity of Bradyrhizobium strains isolated from the host plant, Arachis hypogaea along the coastline of Tamil Nadu. Different populations collected from varying environmental conditions were analysed for salt and pH tolerance. Genetic diversity among the strains was studied using RAPD markers and PCR-RFLP of 16S rDNA and nifD genes. The approaches used in this study yielded consistent results, which revealed a high degree of heterogeneity among strains and detection of two distinct genetic groups.


Assuntos
Arachis/microbiologia , Bradyrhizobium/genética , RNA Ribossômico 16S/análise , DNA Bacteriano/análise , DNA Ribossômico/análise , Genes Bacterianos , Variação Genética , Fixação de Nitrogênio/genética , Polimorfismo de Fragmento de Restrição , Técnica de Amplificação ao Acaso de DNA Polimórfico
20.
Environ Pollut ; 95(3): 319-24, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-15093446

RESUMO

Total cadmium (Cd) and phosphorus (P) concentrations in a pastoral soil, amended annually for 10 years with four forms of P fertilisers, decreased with soil depth. Single superphosphate (SSP) and North Carolina phosphate rock (NCPR) which had higher Cd contents (32 and 41 mg kg(-1), respectively) produced higher total soil Cd than diammonium phosphate (DAP-10 mg kg(-1)), Jordan phosphate rock (JPR-5 mg kg(-1)) and control treatments to a depth of 120 mm. Total soil P in SSP treated plots to a depth of 120 mm and NCPR treated plots to a depth of 75 mm was also higher than the control plots. No significant fertiliser P and Cd moved below 120 mm depth. Approximately 90% of the applied Cd was recovered in the soil of which 93% remained within the top 120 mm. Plant recovery of applied Cd was 1.5-4.5%. Plant available P (Olsen P) also decreased with depth. Plant available Cd (0.01 M CaCl2 extractable Cd) was higher in the 30-75 and 75-120 mm soil depths compared to 0-30 mm soil depth. This may be due to strong adsorption of Cd by the surface soils which have a higher organic matter content and higher pH; factors which are known to increase Cd adsorption in soils

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