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971.
Cirioni O Ghiselli R Kamysz W Orlando F Silvestri C Mocchegiani F Di Matteo F Kamysz E Riva A Rocchi M Saba V Scalise G Giacometti A 《Peptides》2008,29(1):31-38
We investigated the efficacy of tazobactam/piperacillin (TZP), tachyplesin III and granulocyte-colony stimulating factor (G-CSF) in an experimental murine neutropenic intraabdominal infection. BALB/c male mice were rendered neutropenic by intraperitoneal administration of cyclophosphamide on days -4 and -2 pre-infection. Septic shock was induced by cecal ligation and puncture. Animals received intravenously isotonic sodium chloride solution (control group C1), 1mg/kg of tachyplesin III, 120 mg/kg of TZP, 0.1mg/kg of G-CSF, tachyplesin III plus TZP, G-CSF plus TZP and finally tachyplesin III plus G-CSF plus TZP, respectively. Lethality, bacterial growth in blood, peritoneum, spleen, liver, and mesenteric lymph nodes, endotoxin, IL-6 and TNF-alpha concentrations in plasma were evaluated. All compounds reduced the lethality when compared to controls. Endotoxin and cytokine plasma levels were significantly higher in TZP-treated animals compared to tachyplesin III-treated animals. Finally, all drug combinations showed to be the most effective treatment in reducing all variables measured. Interestingly, the strongest results concerning the bacterial growth inhibition, lethality and endotoxemia were obtained when the three compounds were contemporaneously administered. The presence of their positive interaction makes tachyplesin III and G-CSF potentially valuable as an adjuvant for antimicrobial chemotherapy of sepsis. 相似文献
972.
Zarnowska H Borecka A Gawor J Marczyńska M Dobosz S Basiak W 《Journal of helminthology》2008,82(2):123-127
The level of specific anti-Toxocara IgG was examined in 343 children from central Poland with suspected Toxocara infection. Based on the presence of specific IgG antibodies and clinical signs and symptoms, toxocariasis was confirmed in 249 patients. The serological results of diagnosed cases were analysed in connection with epidemiological data (contamination of soil around the children's homes and presence of a dog or a cat). A higher prevalence of soil contamination with Toxocara eggs was found in suburban and rural areas (30.9% and 24.6%, respectively) whereas it was lower in urban areas (10.3%). In about 40% of the children whose households were not contaminated, a decrease in the antibody level was observed 2 years after treatment for toxocariasis, while there was no such decline in those living in contaminated places. The logistic regression model employed to determine the correlation between seropositivity in the children and selected epidemiological risk factors showed a statistically significant relationship in connection only with dog ownership (P = 0.0238). The present results have demonstrated the high risk of toxocariasis for children from rural and suburban areas in Poland. The sero-epidemiological investigations indicated that re-infection might be the reason for persistence of seropositivity after treatment. 相似文献
973.
McCormack JC Yuan X Yingling YG Kasprzak W Zamora RE Shapiro BA Simon AE 《Journal of virology》2008,82(17):8706-8720
The genomes of positive-strand RNA viruses undergo conformational shifts that complicate efforts to equate structures with function. We have initiated a detailed analysis of secondary and tertiary elements within the 3′ end of Turnip crinkle virus (TCV) that are required for viral accumulation in vivo. MPGAfold, a massively parallel genetic algorithm, suggested the presence of five hairpins (H4a, H4b, and previously identified hairpins H4, H5, and Pr) and one H-type pseudoknot (Ψ3) within the 3′-terminal 194 nucleotides (nt). In vivo compensatory mutagenesis analyses confirmed the existence of H4a, H4b, Ψ3 and a second pseudoknot (Ψ2) previously identified in a TCV satellite RNA. In-line structure probing of the 194-nt fragment supported the coexistence of H4, H4a, H4b, Ψ3 and a pseudoknot that connects H5 and the 3′ end (Ψ1). Stepwise replacements of TCV elements with the comparable elements from Cardamine chlorotic fleck virus indicated that the complete 142-nt 3′ end, and subsets containing Ψ3, H4a, and H4b or Ψ3, H4a, H4b, H5, and Ψ2, form functional domains for virus accumulation in vivo. A new 3-D molecular modeling protocol (RNA2D3D) predicted that H4a, H4b, H5, Ψ3, and Ψ2 are capable of simultaneous existence and bears some resemblance to a tRNA. The related Japanese iris necrotic ring virus does not have comparable domains. These results provide a framework for determining how interconnected elements participate in processes that require 3′ untranslated region sequences such as translation and replication. 相似文献
974.
Simon Ladevèze Elisabeth Laville Jordane Despres Pascale Mosoni Gabrielle Potocki‐Véronèse 《Biological reviews of the Cambridge Philosophical Society》2017,92(4):1969-1990
Mannosides constitute a vast group of glycans widely distributed in nature. Produced by almost all organisms, these carbohydrates are involved in numerous cellular processes, such as cell structuration, protein maturation and signalling, mediation of protein–protein interactions and cell recognition. The ubiquitous presence of mannosides in the environment means they are a reliable source of carbon and energy for bacteria, which have developed complex strategies to harvest them. This review focuses on the various mannosides that can be found in nature and details their structure. It underlines their involvement in cellular interactions and finally describes the latest discoveries regarding the catalytic machinery and metabolic pathways that bacteria have developed to metabolize them. 相似文献
975.
Tomasz Plonek Malgorzata Zak Karolina Burzynska Bartosz Rylski Anna Gozdzik Wojciech Kustrzycki Friedhelm Beyersdorf Marek Jasinski Jaroslaw Filipiak 《BMC cardiovascular disorders》2017,17(1):297
Background
Biomechanical factors influence stress in the aortic wall. The aim of this study was to assess how the diameter and shape of the vessel, blood pressure and longitudinal systolic aortic stretching (SAS) caused by the contraction of the myocardium influence stress in the aortic wall.Methods
Three computational models of the non-dilated aorta and aneurysms of the ascending aorta and aortic root were created. Then, finite elements analyses were carried out. The models were subjected to blood pressure (120 mmHg and 160 mmHg) and longitudinal systolic aortic stretching (0 mm, 5 mm, 10 mm and 15 mm). The influence of wall elasticity was examined too.Results
Blood pressure had a smaller impact on the stress than the SAS. An increase in blood pressure from 120 mmHg to 160 mmHg increased the peak wall stress (PWS) on average by 0.1 MPa in all models. A 5 mm SAS caused a 0.1–0.2 MPa increase in PWS in all the models. The increase in PWS caused by a 10 mm and 15 mm SAS was 0.2 MPa and 0.4 MPa in the non-dilated aorta, 0.2–0.3 MPa and 0.3–0.5 MPa in the aneurysm of the ascending aorta, and 0.1–0.2 MPa and 0.2–0.3 MPa in the aortic root aneurysm model, respectively. The loss of elasticity of the aneurysmal wall resulted in an increase of PWS by 0.1–0.2 MPa.Conclusions
Aortic geometry, wall stiffness, blood pressure and SAS have an impact on PWS. However, SAS had the biggest impact on wall stress. The results of this study may be useful in future patient-specific computational models used to assess the risk of aortic complications.976.
977.
Molecularly Engineered Phthalocyanines as Hole‐Transporting Materials in Perovskite Solar Cells Reaching Power Conversion Efficiency of 17.5%
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Kyung Teak Cho Olga Trukhina Cristina Roldán‐Carmona Mine Ince Paul Gratia Giulia Grancini Peng Gao Tomasz Marszalek Wojciech Pisula Paidi Y. Reddy Tomás Torres Mohammad Khaja Nazeeruddin 《Liver Transplantation》2017,7(7)
Easily accessible tetra‐5‐hexylthiophene‐, tetra‐5‐hexyl‐2,2′‐bisthiophene‐substituted zinc phthalocyanines (ZnPcs) and tetra‐tert ‐butyl ZnPc are employed as hole‐transporting materials in mixed‐ion perovskite [HC(NH2)2]0.85(CH3NH3)0.15Pb(I0.85Br0.15)3 solar cells, reaching the highest power conversion efficiency (PCE) so far for phthalocyanines. Results confirm that the photovoltaic performance is strongly influenced by both, the individual optoelectronic properties of ZnPcs and the aggregation of these tetrapyrrolic semiconductors in the solid thin film. The optimized devices exhibit PCE of 15.5% when using tetra‐5‐hexyl‐2,2′‐bisthiophene substituted ZnPcs, 13.3% for tetra‐tert ‐butyl ZnPc, and a record 17.5% for tetra‐5‐hexylthiophene‐based analogue under standard global 100 mW cm?2 AM 1.5G illumination. These results boost up the potential of solution‐processed ZnPc derivatives as stable and economic hole‐transport materials for large‐scale applications, opening new frontiers toward a realistic, efficient, and inexpensive energy production. 相似文献
978.
979.
Feng Zhang Lorraine Potocki Jacinda B. Sampson Amarilis Sanchez-Valle Alicia Delicado Navarro J. Edward Spence Marjorie A. Withers 《American journal of human genetics》2010,86(3):462-588
Nonallelic homologous recombination (NAHR) can mediate recurrent rearrangements in the human genome and cause genomic disorders. Smith-Magenis syndrome (SMS) and Potocki-Lupski syndrome (PTLS) are genomic disorders associated with a 3.7 Mb deletion and its reciprocal duplication in 17p11.2, respectively. In addition to these common recurrent rearrangements, an uncommon recurrent 5 Mb SMS-associated deletion has been identified. However, its reciprocal duplication predicted by the NAHR mechanism had not been identified. Here we report the molecular assays on 74 subjects with PTLS-associated duplications, 35 of whom are newly investigated. By both oligonucleotide-based comparative genomic hybridization and recombination hot spot analyses, we identified two cases of the predicted 5 Mb uncommon recurrent PTLS-associated duplication. Interestingly, the crossovers occur in proximity to a recently delineated allelic homologous recombination (AHR) hot spot-associated sequence motif, further documenting the common hot spot features shared between NAHR and AHR. An additional eight subjects with nonrecurrent PTLS duplications were identified. The smallest region of overlap (SRO) for all of the 74 PTLS duplications examined is narrowed to a 125 kb interval containing only RAI1, a gene recently further implicated in autism. Sequence complexities consistent with DNA replication-based mechanisms were identified in four of eight (50%) newly identified nonrecurrent PTLS duplications. Our findings of the uncommon recurrent PTLS-associated duplication at a relative prevalence reflecting the de novo mutation rate and the distribution of 17p11.2 duplication types in PTLS reveal insights into both the contributions of new mutations and the different underlying mechanisms that generate genomic rearrangements causing genomic disorders. 相似文献
980.
Bal Wojciech Dyba Marcin Szewczuk Zbigniew Jeżowska‐Bojczuk Małgorzata Lukszo Jan Ramakrishna Gayatri Kasprzak Kazimierz S. 《Molecular and cellular biochemistry》2001,222(1-2):97-106
The Zn(II) binding by partial peptides of human protamine HP2: HP21–15; HP21–25, HP226–40, HP237–47, and HP243–57 was studied by circular dichroism (CD). Precipitation of a 20mer DNA by these partial peptides and the effects of Zn(II) thereon were investigated using polyacrylamide gel electrophoresis (GE). The results of this study suggest that reduced HP2 (thiol groups intact) can bind Zn(II) at various parts of the molecule. In the absence of DNA, the primary Zn(II) binding site in reduced HP2 is located in the 37–47 sequence (involving Cys37, His39, His43, and Cys47), while in the presence of DNA, the strongest Zn(II) binding is provided by sequences 12–22 (by His12, Cys13, His19, and His22) and 43–57 (His43, Cys47, Cys53, and His57). In its oxidized form, HP2 can bind zinc through His residues of the 7–22 sequence. Zn(II) markedly enhances DNA binding by all partial peptides. These findings suggest that Zn(II) ions may be a regulatory factor for sperm chromatin condensation processes. 相似文献