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81.
Nídia Cangi Ivan G. Horak Dmitry A. Apanaskevich Sonja Matthee Luís C. B. G. das Neves Agustín Estrada-Pe?a Conrad A. Matthee 《PloS one》2013,8(10)
A comparative phylogeographic study on two economically important African tick species, Amblyomma hebraeum and Hyalomma rufipes was performed to test the influence of host specificity and host movement on dispersion. Pairwise AMOVA analyses of 277 mtDNA COI sequences supported significant population differentiation among the majority of sampling sites. The geographic mitochondrial structure was not supported by nuclear ITS-2 sequencing, probably attributed to a recent divergence. The three-host generalist, A. hebraeum, showed less mtDNA geographic structure, and a lower level of genetic diversity, while the more host-specific H. rufipes displayed higher levels of population differentiation and two distinct mtDNA assemblages (one predominantly confined to South Africa/Namibia and the other to Mozambique and East Africa). A zone of overlap is present in southern Mozambique. A mechanistic climate model suggests that climate alone cannot be responsible for the disruption in female gene flow. Our findings furthermore suggest that female gene dispersal of ticks is more dependent on the presence of juvenile hosts in the environment than on the ability of adult hosts to disperse across the landscape. Documented interspecific competition between the juvenile stages of H. rufipes and H. truncatum is implicated as a contributing factor towards disrupting gene flow between the two southern African H. rufipes genetic assemblages. 相似文献
82.
83.
Martins Alexsandro Sozar Junior João Batista Pereira de Araújo Gomes Adriano Carvalho Fábio Israel Martins Filho Heronides Adonias Dantas das Graças Fernandes Dantas Kelly 《Biological trace element research》2020,194(1):284-294
Biological Trace Element Research - This study reports the simultaneous determination of the total concentrations of Al, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, and Zn in 17 ... 相似文献
84.
de Barros AL Mota LG Soares DC Coelho MM Oliveira MC Cardoso VN 《Bioorganic & medicinal chemistry letters》2011,21(24):7373-7375
Long-circulating and pH-sensitive liposomes trapping 99mTc-HYNIC-βAla-bombesin(7–14) (aSpHL-99mTc-BBN(7–14)) were successfully prepared. Biodistribution studies and scintigraphic images were performed in Ehrlich tumor-bearing Swiss mice. This system showed high accumulation in tumor tissue with high tumor-to-muscle ratio. Therefore, aSpHL-99mTc-BBN(7–14) could be considered as a potential agent for tumor diagnosis. 相似文献
85.
Beatson SA das Graças de Luna M Bachmann NL Alikhan NF Hanks KR Sullivan MJ Wee BA Freitas-Almeida AC Dos Santos PA de Melo JT Squire DJ Cunningham AF Fitzgerald JR Henderson IR 《Journal of bacteriology》2011,193(5):1286-1287
Aeromonas caviae is a Gram-negative, motile and rod-shaped facultative anaerobe that is increasingly being recognized as a cause of diarrhea in children. Here we present the first genome sequence of an A. caviae strain that was isolated as the sole pathogen from a child with profuse diarrhea. 相似文献
86.
Borges AM Dias e Souza M Fiaccadori FS Cardoso DD 《Memórias do Instituto Oswaldo Cruz》2011,106(4):499-501
The epidemiological features of rotavirus A (RVA) infection differ between children from developing and developed countries which could result in differences in vaccine efficacy around the world. To evaluate the impact of Rotarix? on RVA prevalence, we monitored RVA genotypes circulating in Goiania by monitoring virus in faecal samples from children that had or had not been previously vaccinated. From February-November of 2008, 220 faecal samples were collected from children in seven day-care centres. RVA detection was performed by two methodologies and the results were confirmed by polyacrylamide gel electrophoresis. From the 220 samples, eight were RVA-positive (3.6%) and five were from children that had received either one or two doses of the vaccine. All positive samples were collected from children with diarrhoea during August and September. Genotyping of the RVA characterised five of the viral samples as genotype G2P[4] and one as G8P[4], suggesting that G2P[4] was the predominant circulating genotype in Goiania during the study. The fact that vaccinated children were also infected by RVA suggests that the vaccine does not fully protect against infection by the G2[P4] RVA genotype. 相似文献
87.
Burns FJ Tang MS Frenkel K Nádas A Wu F Uddin A Zhang R 《Radiation and environmental biophysics》2007,46(2):195-199
Quantitative cancer incidence data exist for various laboratory animal models, but little of this information is usable for
estimating human risks, primarily because of uncertainties about possible mechanistic differences among species. Acceptance
and utilization of animal data for human risk assessment will require a much better understanding of the comparative underlying
mechanisms than now exists. A dual-lesion, radiation-track model in rat skin has proven to be consistent with tumor induction
data with respect to acute radiation doses ranging from 0.5 up to 10 Gy and higher, and average LETs ranging from 0.34 to
150 keV μm−1 according to the form neoplastic risk (D,L) = CLD + BD2. A recent result with the 56Fe ion beam showed dose-response consistency for malignant (carcinomas) and benign (fibromas) tumor induction with earlier
results utilizing argon and neon ion beams. A discrepancy between the model and experiment was found indicating that proportionality
of cancer yield with LET did not occur at 150 versus 125 keV μm−1, i.e. tumor yield did not increase in spite of a 20% increase of LET, which suggests that a LET response maximum exists at
or within this dose range. Concordance between the model and tumor induction data in rat skin implies that potential intervening
complexities of carcinogenic progression fail to obscure the basic radiobiological assumptions underpinning the model. Gene
expression microarray analysis shows that vitamin A inhibits the expression of about 80% of the inflammation-related genes
induced by the radiation and prevents about 46% of the neoplasms associated with 56Fe ion radiation without appearing to interfere with the underlying dose and LET response patterns. Further validation is
needed, but the model has the potential to provide quantitative estimates of cancer risk as a function of dose and LET for
almost any type of radiation exposure and even for combinations of different radiations provided only three empirical parameters
can be established for each type of radiation and organ system. 相似文献
88.
Mariana Concei??o Souza Tatiana Almeida Padua Natalia Domingos Torres Maria Fernanda de Souza Costa Victor Facchinetti Claudia Regina Brand?o Gomes Marcus Vinícius Nora Souza Maria das Gra?as Henriques 《Memórias do Instituto Oswaldo Cruz》2015,110(4):560-565
A rapid decrease in parasitaemia remains the major goal for new antimalarial drugs
and thus, in vivo models must provide precise results concerning parasitaemia
modulation. Hydroxyethylamine comprise an important group of alkanolamine compounds
that exhibit pharmacological properties as proteases inhibitors that has already been
proposed as a new class of antimalarial drugs. Herein, it was tested the antimalarial
property of new nine different hydroxyethylamine derivatives using the green
fluorescent protein (GFP)-expressing Plasmodium berghei strain. By
comparing flow cytometry and microscopic analysis to evaluate parasitaemia
recrudescence, it was observed that flow cytometry was a more sensitive methodology.
The nine hydroxyethylamine derivatives were obtained by inserting one of the
following radical in the para position: H, 4Cl, 4-Br, 4-F, 4-CH3,
4-OCH3, 4-NO2, 4-NH2 and 3-Br. The antimalarial test showed that the compound that
received the methyl group (4-CH3) inhibited 70% of parasite growth. Our results
suggest that GFP-transfected P. berghei is a useful tool to study the recrudescence
of novel antimalarial drugs through parasitaemia examination by flow cytometry.
Furthermore, it was demonstrated that the insertion of a methyl group at the
para position of the sulfonamide ring appears to be critical for
the antimalarial activity of this class of compounds. 相似文献
89.
Sebastián Pita Yanina Panzera Vera Lúcia da Silva Valente Zilpa das Graças Silva de Melo Carolina Garcia Ana Cristina Lauer Garcia Martín Alejandro Montes Claudia Rohde 《Genetica》2014,142(5):397-403
Comparative genomics in Drosophila began in 1940, when Muller stated that the ancestral haploid karyotype of this genus is constituted by five acrocentric chromosomes and one dot chromosome, named A to F elements. In some species of the willistoni group such as Drosophila willistoni and D. insularis, the F element, instead of a dot chromosome, has been incorporated into the E element, forming chromosome III (E + F fusion). The aim of this study was to investigate the scope of the E + F fusion in the willistoni group, evaluating six other species. Fluorescent in situ hybridization was used to locate two genes of the F element previously studied—cubitus interruptus (ci) and eyeless (ey)—in species of the willistoni and bocainensis subgroups. Moreover, polytene chromosome photomaps corresponding to the F element (basal portion of chromosome III) were constructed for each species studied. In D. willistoni, D. paulistorum and D. equinoxialis, the ci gene was located in subSectction 78B and the ey gene in 78C. In D. tropicalis, ci was located in subSection 76B and ey in 76C. In species of the bocainensis subgroup, ci and ey were localized, respectively, at subsections 76B and 76C in D. nebulosa and D. capricorni, and 76A and 76C in D. fumipennis. Despite the differences in the subsection numbers, all species showed the same position for ci and ey. The results confirm the synteny of E + F fusion in willistoni and bocainensis subgroups, and allow estimating the occurrence of this event at 15 Mya, at least. 相似文献
90.
Ana Paula Alves-Silva Luísa Ant?nia Campos Barros Júlio Cézar Mário Chaul Silvia das Gra?as Pompolo 《PloS one》2014,9(11)
In the present study, the first cytogenetic data was obtained for the ant species Strumigenys louisianae, from a genus possessing no previous cytogenetic data for the Neotropical region. The chromosome number observed was 2n = 4, all possessing metacentric morphology. Blocks rich in GC base pairs were observed in the interstitial region of the short arm of the largest chromosome pair, which may indicate that this region corresponds to the NORs. The referred species presented the lowest chromosome number observed for the subfamily Myrmicinae and for the Hymenoptera found in the Neotropical region. Observation of a low chromosome number karyotype has been described in Myrmecia croslandi, in which the occurrence of tandem fusions accounts for the most probable rearrangement for its formation. The accumulation of cytogenetic data may carry crucial information to ensure deeper understanding of the systematics of the tribe Dacetini. 相似文献