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61.
Blanco YC Farias AS Goelnitz U Lopes SC Arrais-Silva WW Carvalho BO Amino R Wunderlich G Santos LM Giorgio S Costa FT 《PloS one》2008,3(9):e3126
Background
Cerebral malaria (CM) is a syndrome characterized by neurological signs, seizures and coma. Despite the fact that CM presents similarities with cerebral stroke, few studies have focused on new supportive therapies for the disease. Hyperbaric oxygen (HBO) therapy has been successfully used in patients with numerous brain disorders such as stroke, migraine and atherosclerosis.Methodology/Principal Findings
C57BL/6 mice infected with Plasmodium berghei ANKA (PbA) were exposed to daily doses of HBO (100% O2, 3.0 ATA, 1–2 h per day) in conditions well-tolerated by humans and animals, before or after parasite establishment. Cumulative survival analyses demonstrated that HBO therapy protected 50% of PbA-infected mice and delayed CM-specific neurological signs when administrated after patent parasitemia. Pressurized oxygen therapy reduced peripheral parasitemia, expression of TNF-α, IFN-γ and IL-10 mRNA levels and percentage of γδ and αβ CD4+ and CD8+ T lymphocytes sequestered in mice brains, thus resulting in a reduction of blood-brain barrier (BBB) dysfunction and hypothermia.Conclusions/Significance
The data presented here is the first indication that HBO treatment could be used as supportive therapy, perhaps in association with neuroprotective drugs, to prevent CM clinical outcomes, including death. 相似文献62.
Ugurel S Schrama D Keller G Schadendorf D Bröcker EB Houben R Zapatka M Fink W Kaufman HL Becker JC 《Cancer immunology, immunotherapy : CII》2008,57(5):685-691
Purpose Chemokines influence both tumor progression and anti-tumor immune response. A 32-bp-deletion polymorphism in the chemokine
receptor 5 gene (CCR5Δ32) has been shown to result in a non-functional protein. This study was aimed at evaluating the potential
impact of this gene polymorphism on disease progression and treatment outcome in patients with melanoma.
Patients and methods CCR5 genotyping was performed by PCR on DNA extracted from serum samples of 782 cutaneous melanoma patients with known disease
history and long-term clinical follow-up. Genotypes were correlated with patient survival and types of treatment.
Results Of 782 melanoma patients, 90 (11.5%) were heterozygous and 12 (1.5%) were homozygous for CCR5Δ32. Analyzing the complete cohort,
the disease-specific survival from date of primary diagnosis was not influenced by CCR5 status. Similarly, no significant
impact could be detected on the treatment outcome of stage III patients. In 139 stage IV patients receiving immunotherapy,
CCR5Δ32 was associated with a decreased survival compared to patients not carrying the deletion (median 12.5 vs. 20.3 months,
P = 0.029). Multivariate analysis revealed the CCR5 genotype as an independent factor impacting disease-specific survival in
this patient population (P = 0.002), followed by gender (P = 0.019) and pathological classification of the primary (pT; P = 0.022).
Conclusion The presence of the CCR5Δ32 polymorphism in patients with stage IV melanoma results in a decreased survival following immunotherapy
and may help to select patients less likely to benefit from this type of treatment.
Selma Ugurel and David Schrama have contributed equally to this work. 相似文献
63.
Three hundred and thirty nine lactic bacteria strains isolated from food samples were screened for antimicrobial activity.
Only one strain isolated from meat pie and identified as Enterococcus faecium produced a bacteriocin-like inhibitory substance (BLIS) showing activity against Enterococcus, Leuconostoc, Lactobacillus, Listeria, Corynebacterium and Staphylococcus aureus. The BLIS produced was resistant to acid and alkali treatment and 121oC for 15 min. The addition of BLIS in BHI contaminated
with Listeria monocytogenes decreased the contamination in 4.8 log cycles in 24 h. The inhibition of listeria was also obtained in milk. Forty multiresistant
enterococci strains were inhibited in the well-diffusion test. Two vancomycin resistant strains tested in liquid with BLIS
were also inhibited. The BLIS producer showed no pathogenicity marker. 相似文献
64.
Background
Mutations in the core promoter and precore regions of the hepatitis B virus (HBV) genome, notably the double substitution (AGG to TGA) at nt positions 1762-1764 in the core promoter, and the precore stop codon mutation G to A at nt 1896, can often explain the anti-HBe phenotype in chronic carriers. However, the A1896 mutation is restricted to HBV isolates that have T at nt 1858. The double substitution at positions 1762-1764 has been described to occur preferentially in patients infected with strains showing C instead of T at nt 1858. 相似文献65.
Selma Soares de Oliveira Sandra Amaral de Araújo Maria do Carmo de Freire Bastos 《FEMS microbiology letters》1993,106(2):123-127
Abstract A 5.8-kb Cla I fragment of pRJ9, a bacteriocinogenic plasmid of Sphylococcus aureus , was cloned in the unique Cla I site of pRJ5. The recombinant plasmid obtained, pRJ23, failed to confer bacteriocin production and immunity to bacteriocin on host cells. The cloned fragment was shown to contain the complete replicon of pRJ9. Attempts to clone the 4.4-kb Cla I fragment of pRJ9 were unsuccessful, apparently due to the inactivation of the basic replicon of the cloning vector. Therefore, plasmid pRJ5 cut at its Cla I site appears to be a suitable vector for cloning replication regions of plasmids that cab replicate in S. aureus . 相似文献
66.
As the human population grows, the demand for living space and supplies of resources also increases, which may induce rapid change in land-use/land-cover (LULC) and associated pressures exerted on aquatic habitats. We propose a new approach to forecast the impact of regional land cover change and water management policies (i.e., targets in nutrient loads reduction) on lake and reservoir water eutrophication status using a model that requires minimal parameterisation compared with alternative methods. This approach was applied to a set of 48 periurban lakes located in the Ile de France region (IDF, France) to simulate catchment-scale management scenarios. Model outputs were subsequently compared to governmental agencies’ 2030 forecasts. Our model indicated that the efforts made to reduce pressure in the catchment of seepage lakes might be expected to be proportional to the gain that might be obtained, whereas drainage lakes will display little improvement until a critical level of pressure reduction is reached. The model also indicated that remediation measures, as currently planned by governmental agencies, might only have a marginal impact on improving the eutrophication status of lakes and reservoirs within the IDF region. Despite the commitment to appropriately managing the water resources in many countries, prospective tools to evaluate the potential impacts of global change on freshwater ecosystems integrity at medium to large spatial scales are lacking. This study proposes a new approach to investigate the impact of region-scale human-driven changes on lake and reservoir ecological status and could be implemented elsewhere with limited parameterisation. Issues are discussed that relate to model uncertainty and to its relevance as a tool applied to decision-making. 相似文献
67.
68.
Brachypodium distachyon as alternative model host system for the ergot fungus Claviceps purpurea
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Sabine Kind Selma Schurack Janine Hinsch Paul Tudzynski 《Molecular Plant Pathology》2018,19(4):1005-1011
To investigate its susceptibility to ergot infection, we inoculated Brachypodium distachyon with Claviceps purpurea and compared the infection symptoms with those on rye (Secale cereale). We showed that, after inoculation of Brachypodium with Claviceps, the same disease symptoms occurred in comparable temporal and spatial patterns to those on rye. The infection rate of Claviceps on this host was reduced compared with rye, but the disease could be surveyed by fungal genomic DNA quantification. Mutants of Claviceps which were virulence attenuated on rye were also affected on Brachypodium. We were able to show that pathogenesis‐related gene expression changed in a typical manner for biotrophic pathogen attack. Our results indicated that the Claviceps–Brachypodium interaction was dependent on salicylic acid, cytokinin and auxin. We consider Brachypodium to be a suitable and useful alternative host; the increased sensitivity compared with rye will be valuable for the identification of infection mechanisms. Future progess in understanding the Claviceps–plant interaction will be facilitated by the use of a well‐characterized model host system. 相似文献
69.
Andrea J Robinson Jomana Elaridi Bianca J Van Lierop Selma Mujcinovic W Roy Jackson 《Journal of peptide science》2007,13(4):280-285
Microwave irradiation dramatically improves the efficiency of ring closing metathesis (RCM) reactions of resin-attached peptides and the technology is illustrated by the highly selective synthesis of dicarba analogues of alpha-conotoxin IMI. 相似文献
70.