Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
J Math Biol ; 82(4): 26, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33649962

RESUMO

The Neolithic transition began the spread of early agriculture throughout Europe through interactions between farmers and hunter-gatherers about 10,000 years ago. Archeological evidences indicate that the expanding velocity of farming into a region occupied by hunter-gatherers is roughly constant all over Europe. In the late twentieth century, from the contribution of the radiocarbon dating, it could be found that there are two types of farmers: one is the original farmer and the other is the converted farmer which is genetically hunter-gatherers but learned agriculture from neighbouring farmers. Then this raises the following questions: Which farming populations play a key role in the expansion of farmer populations in Europe? and what is the fate of hunter-gatherers (e.g., become extinct, or live in lower density, or live in agricultural life-style)? We consider a three-component reaction-diffusion system proposed by Aoki, Shida and Shigesada, which describes the interactions among the original farmers, the converted farmers, and the hunter-gatherers. In order to resolve these two questions, we discuss traveling wave solutions which give the information of the expanding velocity of farmer populations. The main result is that two types of traveling wave solutions exist, depending on the growth rate of the original farmer population and the conversion rate of the hunter-gatherer population to the converted farmer population. The profiles of traveling wave solutions indicate that the expansion of farmer populations is determined by the growth rate of the original farmer and the (maximal) carrying capacity of the converted farmer, and the fate of hunter-gatherers is determined by the growth rate of the hunter-gatherer and the conversion rate of the hunter-gatherer to the converted farmer. Thus, our results provide a partial answer to the above two questions.


Assuntos
Comportamento Apetitivo , Fazendeiros , Modelos Teóricos , Agricultura , Arqueologia , Europa (Continente) , História Antiga , Humanos
2.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-246871

RESUMO

<p><b>OBJECTIVE</b>To investigate the feasibility and therapeutic effect of free posterior interrosseous artery flap in a bridge fashion for combined skin and bilateral artery defects at palmar side of fingers.</p><p><b>METHODS</b>6 cases with combined skin and bilateral artery defects at palmar side of fingers were treated with long-pedicled free posterior interrosseous artery flap in a bridge fashion. The flap size ranged from 3.5 cm x 2.0 cm to 6.5 em x 3.0 cm. The wounds at donor sites were closed directly.</p><p><b>RESULTS</b>All the 6 flaps survived completely without any complication, and the wounds healed primarily. The blood supply and vein drainage in all the 6 fingers were normal. 4 cases were followed up for 1-12 months (average, 7 months). Satisfactory cosmetic and functional results were achieved. The flaps looked a little bit thicker than the surrounding tissue.</p><p><b>CONCLUSIONS</b>The long-pedicled free posterior interrosseous artery flap in a bridge fashion is a good option for reconstruction of the combined skin and bilateral artery defects at palmar side of fingers in one stage.</p>


Assuntos
Humanos , Artérias , Estudos de Viabilidade , Dedos , Cirurgia Geral , Retalhos de Tecido Biológico , Transplante , Procedimentos de Cirurgia Plástica , Retalhos Cirúrgicos , Transplante , Sítio Doador de Transplante , Cirurgia Geral , Veias
3.
Chinese Journal of Epidemiology ; (12): 808-815, 2011.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-241209

RESUMO

Objective The aim of this study was to demonstrate the immunogenicity and safety of diphtheria, tetanus, pertussis (acellular, component) , poliomyelitis (inactivated) vaccine (adsorbed) and Haemophilus influenzae type b conjugate vaccine (DTaP-IPV//PRP-T) combined vaccine compared with commercially available DTaP (diphtheria, tetanus and pertussis), Haemophilus influenzae type b (Hib), tetanus conjugate and IPV monovalent vaccine. Methods Subjects were randomly divided into three groups, Group A and Group B were DTaP-IPV//PRP-T combined vaccine (PENTAXIMTM) vaccinated at 2,3,4 months of age or 3,4, 5 months of age respectively; Group C was commercially available DTaP. Hib tetanus conjugate (Act-HIBTM) and IPV (IMOVAX PolioTM) vaccines vaccinated at 3,4, 5 months of age. All groups received booster dose at 18 to 20 months of age, with antibody titers tested. Non-inferiority analysis was demonstrated in terms of seroprotection / seroconversion rates between Group A, Group B respectively and Group C. Safety information was collected after each vaccination to assess the safety of investigational vaccines. Results The non-inferiority of DTaP-IPV//PRP-T combined vaccine vaccinated at 2,3,4 or 3,4, 5 months of age versus DTaP, Hib tetanus conjugate and IPV vaccine was demonstrated for all vaccine antigens in both primary and booster phases in terms of seroprotection/seroconversion rates. DTaP-IPV//PRP-T combined vaccine was well tolerated. The rate of solicited/unsoliciated severe adverse reactions was very low and similar to the control vaccines. Conclusion DTaP-IPV//PRP-T combined vaccine was highly immunogenic with good safety profile in Chinese infants, which was comparable to the commercially available control vaccines.

4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-642335

RESUMO

Proteomics, which has been widely used in life science, is an emerging discipline following genomics. It can help to explore the pathogenic mechanism and early onset marker of Bacillus anthracis, playing an important part in the prevention, diagnosis and treatment of B.anthracis. In this paper,the application of proteomics in the research of B.anthracis is reviewed.

5.
Microbiology ; (12)1992.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-686191

RESUMO

Monascus spp.,a kind of filamentous fungi,produce abundant of important metabolites which were widely used in the fields of food and medicine.Until now,there are few reports on the important functional genes of the Monascus spp.due to little genetic information.In this paper,the feasibility of gene deletion mediated via Agrobacterium tumefaciens on the basis of homologous recombination was analyzed by studying on the deletion of the RGS domain of putative G-protein signaling regulator gene mrfA in Monascus ruber.The length of homologous arms of deletion vector pC805S were 958 bp and 824 bp,respectively.There were 26 transformants in which homologous recombination occurred in 138 transformants and the recombination rate was 18.8%.The result showed it was feasible to identify the function of unknown gene in M.ruber with the targeted-deletion technology mediated via A.tumefaciens.

6.
Microbiology ; (12)1992.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-685393

RESUMO

This text involved with a pre-enrichment medium for the simultaneous recovery of Salmonella spp.,Escherichia coli and Staphylococcus aureus.This medium is named buffered saline broth(BSB),which contains peptone 10g,beef exact 3g,disodium hydrogen phosphate 9g,potassium dihydrogen phosphate 1.5g,additive 50g,deionized water 1 000mL,pH7.2.1cfu per one milliliter of Salmonella spp.,Escherichia coli and Staphylococcus aureus in saline were stimutaneously added to 97 mL of BSB,buffered peptone water,lactose broth,nutrient broth,Escherichia coli broth,rappaport-vassiliadis enrichment broth,7.5% sodium chloride enrichment medium,respectively,and incubated for 18h at 37℃.The results showed BSB was the best enrichment medium,in which Salmonella spp.,Escherichia coli and Staphylococcus aureus multiplied at nearly same speed,and reached at 10~6 、10~6 、10~7 cfu/mL,respectively.Multiplex PCR produced specific amplicons of expected sizes,284bp for Salmonella spp.invA gene,622bp for Escherichia coli phoA gene,484bp for Staphylococcus aureus nuc gene.In contrast,the three bacteria couldn't multiply harmoniously in the other six media.So BSB might be considered as the medium,which could enrich above mentioned three bacteria.

7.
Microbiology ; (12)1992.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-685225

RESUMO

According to DNA sequences of the invA gene of Salmonella spp.,the phoA gene of Escherichia coli and the nuc gene of Staphylococcus aureus,three pairs of oligonucleotide primers were designed and synthesized to amplify the special DNA sequences by multiplex PCR. Moreover,the reaction conditions of multiplex PCR were optimized. The results showed the multiplex PCR using the three pairs of primers produced specific amplicons of expected sizes,284bp for Salmonella spp.,622bp for Escherichia coli,484bp for Staphylococcus aureus. The optimized reaction conditions followed as the concentration of primer 40nmol/L for Salmonella spp.,40nmol/L for Escherichia coli,80nmol/L for Staphylococcus aureus,2.4mmol/L Mg 2+ ,200?mol/L dNTP,1.5U Taq DNA polymerase,anneal temperature from 55.0℃ to 57.4℃. Under the condition,the detection limits for DNA template were 10.2pg,10.2pg and 102.0pg for Salmonella spp.,Escherichia coli and Staphylococcus aureus,respectively. The whole process could be completed within 4h. The multiplex PCR assay was a specific,sensitive,rapid and reliable method for detecting Salmonella spp.,Escherichia coli and Staphylococcus aureus,which establish important foundation for simultaneous detection for these three bacteria in food.

8.
Microbiology ; (12)1992.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-685099

RESUMO

200 citrinin mutants were screened with the inhibition zone method from the transformants library of Monascus ruber M-7 by Agrobacterium-mediate DNA transfer, which contains more than 5,000 transformants.Then 53 mutants, whose citrinin contents ranged from 0.04?g/g to 154.57?g/g in the red fermented rice (RFR), were achieved by high performance liquid chromatography (HPLC).Color values of RFR prepared by these mutants were also detected.The results showed that there was a positive correlation between the citrinin content and the color value among the mutants.These results provide materials and research bases for ferrther studying the relationship between the production of citrinin and pigment of Monascus ruber at molecular level.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...