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排序方式: 共有423条查询结果,搜索用时 15 毫秒
101.
Cláudio de Oliveira Cunha Luiz Fernando Goda Zuleta Luiz Gonzaga Paula de Almeida Luciane Prioli Ciapina Wardsson Lustrino Borges Rosa Maria Pitard José Ivo Baldani Rosangela Straliotto Sérgio Miana de Faria Mariangela Hungria Benildo Sousa Cavada Fábio Martins Mercante Ana Tereza Ribeiro de Vasconcelos 《Journal of bacteriology》2012,194(23):6675-6676
The genus Burkholderia represents a challenge to the fields of taxonomy and phylogeny and, especially, to the understanding of the contrasting roles as either opportunistic pathogens or bacteria with biotechnological potential. Few genomes of nonpathogenic strains, especially of diazotrophic symbiotic bacteria, have been sequenced to improve understanding of the genus. Here, we contribute with the complete genome sequence of Burkholderia phenoliruptrix strain BR3459a (CLA1), an effective diazotrophic symbiont of the leguminous tree Mimosa flocculosa Burkart, which is endemic to South America. 相似文献
102.
Muchova T Quintal SM Farrell NP Brabec V Kasparkova J 《Journal of biological inorganic chemistry》2012,17(2):239-245
When antitumor platinum drugs react with DNA they form various types of intrastrand and interstrand cross-links (CLs). One
class of new antitumor platinum compounds comprises bifunctional PtII compounds based on the dinuclear or trinuclear geometry of leaving ligands. It has been shown that the DNA-binding modes
of dinuclear or trinuclear bifunctional PtII agents are distinct from those of mononuclear cisplatin, forming markedly more intramolecular interstrand CLs. However, at
least two types of DNA interstrand cross-linking by bifunctional PtII complexes can be envisaged, depending on whether the platinum complex coordinates to the bases in one DNA molecule (intramolecular
interstrand CLs) or in two different DNA duplexes (interduplex CLs). We hypothesized that at least some antitumor bifunctional
poly(di/tri)nuclear complexes could fulfill the requirements placed on interduplex DNA cross-linkers. To test this hypothesis
we studied the interduplex cross-linking capability of a representative of antitumor polynuclear agents, namely, dinuclear
PtII complex [{trans-PtCl(NH3)2}2-μ-{trans-(H2N(CH2)6NH2(CH2)2NH2(CH2)6NH2)}]4+ (BBR3535). The investigations were conducted under molecular crowding conditions mimicking environmental conditions in the
cellular nucleus, namely, in medium containing ethanol, which is a commonly used crowding agent. We found with the aid of
native agarose gel electrophoresis that the DNA interduplex cross-linking efficiency of BBR3535 under molecular crowding conditions
was remarkable: the frequency of these CLs was 54%. In contrast, the interduplex cross-linking efficiency of mononuclear cisplatin
or transplatin was markedly lower (approximately 40-fold or 18-fold, respectively). We suggest that the production of interduplex
CLs in addition to other DNA intramolecular adducts may provide polynuclear PtII compounds with a wider spectrum of cytotoxicity. 相似文献
103.
Encapsulation of Ferritin, Ribosomes, and Ribo-Peptidic Complexes Inside Liposomes: Insights Into the Origin of Metabolism 总被引:1,自引:0,他引:1
Tereza Pereira de Souza Pasquale Stano Frank Steiniger Erica D’Aguanno Emiliano Altamura Alfred Fahr Pier Luigi Luisi 《Origins of life and evolution of the biosphere》2012,42(5):421-428
Here we summarize the main results of our latest investigation on the spontaneous encapsulation of proteins (ferritin) and ribosomes inside lipid vesicles. We show that when vesicles form in a solution containing some macromolecules (even at low concentration), in contrast to the expectations, a few but measurable number of vesicles is able to capture a very high number of solutes, up to 60 times the external concentration. We also show preliminary evidences on the encapsulation of additional solutes (ribo-peptidic complexes, fluorescent proteins and enzymes), and shortly present our current approach aimed at exploiting this phenomenon. In particular, we would like to reveal how the formation of compartments can trigger effective intra-vesicle reactions starting from diluted solutions. Although the mechanistic details for this phenomenon are still missing, we claim that these new evidences are highly relevant for the origin of the first functional cells in primitive times. 相似文献
104.
More than 40% of nosocomial infections are those of the urinary tract, most of these occurring in catheterized patients. Bacterial colonization of the urinary tract and catheters results not only in infection, but also various complications, such as blockage of catheters with crystalline deposits of bacterial origin, generation of gravels and pyelonephritis. The diversity of the biofilm microbial community increases with duration of catheter emplacement. One of the most important pathogens in this regard is Proteus mirabilis. The aims of this study were to identify and assess particular virulence factors present in catheter-associated urinary tract infection (CAUTI) isolates, their correlation and linkages: three types of motility (swarming, swimming and twitching), the ability to swarm over urinary catheters, biofilm production in two types of media, urease production and adherence of bacterial cells to various types of urinary tract catheters. We examined 102 CAUTI isolates and 50 isolates taken from stool samples of healthy people. Among the microorganisms isolated from urinary catheters, significant differences were found in biofilm-forming ability and the swarming motility. In comparison with the control group, the microorganisms isolated from urinary catheters showed a wider spectrum of virulence factors. The virulence factors (twitching motility, swimming motility, swarming over various types of catheters and biofilm formation) were also more intensively expressed. 相似文献
105.
106.
Ruslan Dorfman Weili Li Lei Sun Fan Lin Yongqian Wang Andrew Sandford Peter D. Paré Karen McKay Hana Kayserova Tereza Piskackova Milan Macek Kamila Czerska Dorota Sands Harm Tiddens Sonia Margarit Gabriela Repetto Marci K. Sontag Frank J. Accurso Scott Blackman Garry R. Cutting Lap-Chee Tsui Mary Corey Peter Durie Julian Zielenski Lisa J. Strug 《Human genetics》2009,126(6):763-778
Cystic fibrosis (CF) is a monogenic disease due to mutations in the CFTR gene. Yet, variability in CF disease presentation is presumed to be affected by modifier genes, such as those recently demonstrated for the pulmonary aspect. Here, we conduct a modifier gene study for meconium ileus (MI), an intestinal obstruction that occurs in 16–20% of CF newborns, providing linkage and association results from large family and case–control samples. Linkage analysis of modifier traits is different than linkage analysis of primary traits on which a sample was ascertained. Here, we articulate a source of confounding unique to modifier gene studies and provide an example of how one might overcome the confounding in the context of linkage studies. Our linkage analysis provided evidence of a MI locus on chromosome 12p13.3, which was segregating in up to 80% of MI families with at least one affected offspring (HLOD = 2.9). Fine mapping of the 12p13.3 region in a large case–control sample of pancreatic insufficient Canadian CF patients with and without MI pointed to the involvement of ADIPOR2 in MI (p = 0.002). This marker was substantially out of Hardy–Weinberg equilibrium in the cases only, and provided evidence of a cohort effect. The association with rs9300298 in the ADIPOR2 gene at the 12p13.3 locus was replicated in an independent sample of CF families. A protective locus, using the phenotype of no-MI, mapped to 4q13.3 (HLOD = 3.19), with substantial heterogeneity. A candidate gene in the region, SLC4A4, provided preliminary evidence of association (p = 0.002), warranting further follow-up studies. Our linkage approach was used to direct our fine-mapping studies, which uncovered two potential modifier genes worthy of follow-up. 相似文献
107.
Tereza lapetov Karel mejkal Gabbriella Innocenti Stefano DallAcqua Jrg Heilmann Petr Babula Eva Hamzov Milan
emli
ka 《Carbohydrate research》2009,344(13):1770-1774
Three new nervogenic acid glycosides, 1-O-α-l-rhamnopyranosyl 3,5-bis(3-methyl-but-2-enyl)-4-O-[α-l-rhamnopyranosyl-(1→2)-β-d-glucopyranosyl]-benzoate, 3,5-bis(3-methyl-but-2-enyl)-4-O-[α-l-rhamnopyranosyl-(1→2)-β-d-glucopyranosyl]-benzoic acid, and bis{3,5-bis(3-methyl-but-2-enyl)-4-O-[α-l-rhamnopyranosyl-(1→2)-β-d-glucopyranosyl]-benzoyl} 1,2-O-β-d-glucopyranose, which we named condobulbosides A–C, were isolated from a methanol extract of the leaves of Liparis condylobulbon together with an apigenin C-glycoside, schaftoside. Their structures were established on the basis of spectral techniques, namely, UV, IR, HR-MS spectroscopy, both 1D and 2D NMR experiments, and chemical reactions. 相似文献
108.
Jiri Petrak Ondrej Toman Tereza Simonova Petr Halada Radek Cmejla Pavel Klener Jan Zivny 《Proteomics》2009,9(22):5006-5015
The resistance of malignant cells to chemotherapy calls for the development of novel anti‐cancer drugs. TNF‐related apoptosis‐inducing ligand (TRAIL) is a pro‐apoptotic cytokine, which selectively induces apoptosis in malignant cells. We derived two TRAIL‐resistant HL‐60 subclones, HL‐60/P1 and HL‐60/P2, from a TRAIL‐sensitive HL‐60 acute promyelocytic leukemia cell line. To identify therapeutically exploitable “weaknesses” of the TRAIL‐resistant leukemia cells that could be used as molecular targets for their elimination, we performed proteomic (2‐DE) analysis and compared both TRAIL‐resistant subclones with the original TRAIL‐sensitive HL‐60 cells. We identified over 40 differentially expressed proteins. To significantly narrow the lists of candidate proteins, we excluded proteins that are known to be often differentially expressed, regardless of experiment type and tissue (the so‐called “TOP15” proteins). Decreased expression of DNA replication and maintenance proteins MCM7 and RPA32 in HL‐60/P1 cells, and the marked down‐regulation of enzyme adenosine deaminase in HL‐60/P2 cells, suggests increased sensitivity of these cells to DNA‐interfering drugs, and adenosine and its homologues, respectively. In a series of in vitro assays, we confirmed the increased toxicity of etoposide and cisplatin to TRAIL resistant HL‐60/P1 cells, and adenosine and vidarabine to HL‐60/P2, compared with TRAIL‐sensitive HL‐60 cells. 相似文献
109.
Fabiana G. S. Pinto Ligia M. O. Chueire Ana Tereza R. Vasconcelos Marisa F. Nicolás Luiz G. P. Almeida Rangel C. Souza Pâmela Menna Fernando G. Barcellos Manuel Megías Mariangela Hungria 《Functional & integrative genomics》2009,9(2):263-270
Rhizobium tropici is representative of the diversity of tropical rhizobia, besides comprising strains very effective in fixing N2 in symbiosis with the common bean (Phaseolus vulgaris L.). The genome of a Brazilian commercial inoculant R. tropici strain (PRF 81, =SEMIA 4088), estimated at 7.85 Mb, was analyzed through a total of 9,026 shotgun reads, assembled in 1,668
phrap contigs, and covering ≈30% of the genome. Annotation identified 2,135 coding DNA sequences (CDS), and only 57.2% have
possible functions. The genome comprises a mosaic of genes, with CDS showing the highest similarities with 134 microorganisms,
none of which represents more than 19% of the CDS with putative known functions. The high saprophytic capacity of PRF 81 may
reside in a variety of genes related to transport, biodegradation of xenobiotics, defense, and secretion proteins, many of
which were reported for the first time in the present study. Novelty was also found in nodulation (nodG, a double nodIJ system, nodT, nolF, nolG) and capsular polysaccharide genes, showing stronger similarities with Sinorhizobium (=Ensifer) than with the main symbionts of the common bean—R. etli and R. leguminosarum—suggesting that the original host of R. tropici might be another tropical legume or emphasizing the highly promiscuous nature of this rhizobial species. 相似文献
110.