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51.
52.
Ho Young Yune Sung Phil Chung Yoo Seok Park Hyun Soo Chung Hye Sun Lee Jong Wook Lee Jong Woo Park Je Sung You Incheol Park Hahn Shick Lee 《PloS one》2015,10(3)
Background
The post-resuscitation phase after out-of-hospital cardiac arrest (OHCA) is characterised by a systemic inflammatory response (e.g., severe sepsis), for which the immature granulocyte count is a diagnostic marker. In this study we evaluated the prognostic significance of the delta neutrophil index (DNI), which is the difference in leukocyte subfractions as assessed by an automated blood cell analyser, for early mortality after OHCA.Materials and Methods
OHCA records from the emergency department cardiac arrest registry were retrospectively analysed. Patients who survived at least 24 h after return of spontaneous circulation were included in the analysis. We evaluated mortality and cerebral performance category scores at 30 days.Results
A total of 83 patients with OHCA were included in the study. Our results showed that DNI >8.4% on day 1 (hazard ratio [HR], 3.227; 95% CI, 1.485–6.967; p = 0.001) and DNI >10.5% on day 2 (HR, 3.292; 95% CI, 1.662–6.519; p<0.001) were associated with increased 30-day mortality in patients with OHCA. Additionally, DNI >8.4% on day 1 (HR, 2.718; 95% CI, 1.508–4.899; p<0.001) and DNI >10.5% on day 2 (HR, 1.709; 95% CI, 1.051–2.778; p = 0.02) were associated with worse neurologic outcomes 30 days after OHCA.Conclusion
A higher DNI is a promising prognostic marker for 30-day mortality and neurologic outcomes after OHCA. Our findings indicate that patients with elevated DNI values after OHCA might be closely monitored so that appropriate treatment strategies can be implemented. 相似文献53.
Hepatitis B virus X protein is a major factor in the HBV-induced disease developments. Stromal cell-derived factor-1 is a small cytokine that is strongly chemotactic for lymphocytes. We explored the role of HBx on recruitment of HBV-induced virus-nonspecific immune cells into liver. Immune cell recruitment and SDF-1 expression level significantly increased in livers of HBx-transgenic mice and X-box binding protein-1 significantly increased SDF-1 gene expression. Finally, we confirmed that immune cell recruitment into liver tissues of HBx-TG mice was diminished by a chemokine receptor antagonist. Therefore, HBx increases ER stress-dependent SDF-1 expression and induces HBV-induced immune cell recruitment into liver. 相似文献
54.
Young-Jin Je Dae-Kyoung ChoiKyung-Cheol Sohn Hyeong-Rae KimMyung Im Young LeeJeung-Hoon Lee Chang-Deok Kim Young-Joon Seo 《Biochemical and biophysical research communications》2014
Inhibitor of DNA binding 1 (Id1) is a basic helix-loop-helix (bHLH) protein that has a variety of functional roles in cellular events including differentiation, cell cycle and cancer development. In addition, it has been demonstrated that Id1 is related with TGF-β and Smad signaling in various biological conditions. In this study, we investigated the effect of Id1 on TGF-β-induced collagen expression in human dermal fibroblasts. When Id1-b isoform was overexpressed, TGF-β-induced collagen expression was markedly inhibited. Consistent with this result, Id1-b significantly inhibited TGF-β-induced collagen gel contraction. In addition, Id1-b inhibited TGF-β-induced phosphorylation of Smad2 and Smad3. Finally, immunohistochemistry showed that Id1 expression was decreased in fibrotic skin diseases while TGF-β signaling was increased. Together, these results suggest that Id1 is an inhibitory regulator on TGF-β-induced collagen expression in dermal fibroblasts. 相似文献
55.
Ko Woon Lee Kyoungseon Min Kyungmoon Park Young Je Yoo 《Biotechnology and Bioprocess Engineering》2010,15(4):603-607
Biodiesel has been greatly interested as an alternative fuel and is produced by a transesterification reaction of oil with
alcohol. Recently, microbial lipases have been used for biodiesel production. Among the microbial lipase, immobilized Candida antartica lipase B (CALB) is the most widely used. However, CALB is unstable and shows low catalytic efficiency in the reaction media
because the reaction media contains a high concentration of methanol and the lipase is also inhibited by the by-product glycerol.
In this study, to overcome these limitations, we developed an amphiphilic matrix to immobilize CALB. The immobilized lipase
in an amphiphilic matrix with 80% ethyltrimethoxysilane (ETMS) in tetramethoxysilane (TMOS) and pretreated with oil showed
the highest specific activity and biodiesel conversion ratio; about 90% biodiesel conversion in 24 h at an initial molar ratio
of 1: 1 (oil: methanol) with stepwise methanol feeding in order to adjust the net molar ratio to be 1: 3. 相似文献
56.
Microbial communities in hot pepper (Capsicum annuum L.) cultivation fields under different cultivation methods were investigated by terminal restriction fragment length polymorphism
(T-RFLP) analysis. Rhizosphere soil and leaf samples were collected from control, conventional and nature-friendly cultivation
fields between May and July, 2009. Two Bacillus subtilis strains were applied to nature-friendly cultivation fields as biocontrol agents during the sampling period. Relative abundances
of bacteria and plant pathogenic fungi related T-RFs were also measured to monitor the effect of biocontrol agents on potential
plant pathogenic fungi. In the principal component analysis (PCA) based on T-RFLP profiles, the microbial communities from
rhizosphere soil samples in July, including bacteria and fungi, showed distinct difference between nature-friendly cultivation
fields and other cultivation fields. However, there was no correlation between cultivation methods and leaf microbial communities
at any sampling period. Changes in the abundance of bacteria related T-RF in the rhizosphere of nature-friendly cultivation
fields were observed clearly two months after application of biocontrol agent, while the abundance of plant pathogenic fungi
related T-RFs significantly decreased. 相似文献
57.
Petr Niederhafner Lucie Bednárová Miloš Buděšínský Martin Šafařík Sille Ehala Jan Ježek Lenka Borovičková Vladimír Fučík Václav Čeřovský Jiřina Slaninová 《Amino acids》2010,39(5):1553-1561
The recently described antimicrobial peptide melectin (MEP, GFLSILKKVLPKVMAHMK-NH2) exhibits high antimicrobial activity against Gram-positive and Gram-negative bacteria. Here we describe the synthesis and biological activities of 23 new analogues of MEP. We studied the influence of dimerization and tetramerization (MAP-constructs of MEP) on the antimicrobial and hemolytic activities, as well as the role of Met in positions 14 and 17 of the peptide chain. Oxidation of the Met to Met(O) and Met(O2) decreases antimicrobial activity of all tested bacteria if the peptide is in the monomeric form, however, only to Staphylococcus aureus if in the form of dimer or tetramer. Dimerization and tetramerization increase the undesirable hemolytic activity of the peptides. Interestingly, substitution of Leu for Val in position 6 leads to the decrease of hemolytic activity. Introduction of the isosteric amino acid Nle into positions 14 or 17 or both leads to slight increase of hemolytic activity under preservation of high antimicrobial activities. Unfortunately, dimerization again leads to an increase of hemolytic activity. 相似文献
58.
Mikhail Yu. Ozerov Alexey Je. Veselov Jaakko Lumme Craig R. Primmer 《Conservation Genetics》2010,11(5):1711-1724
Freshwater Atlantic salmon (Salmo salar L.) populations are a living example of adaptation to the changing conditions caused by glacial cycles. The uniqueness of
these populations is emphasized by almost complete resistance to the dangerous parasite Gyrodactylus salaris. In Europe, freshwater salmon populations occur primarily in north-western Russia in the republic of Karelia. These systems
include Lakes Ladoga and Onega, the two largest lakes in Europe, each of which harbours a number of freshwater salmon spawning
rivers. We used microsatellite markers to study the genetic structure and temporal stability of 11 freshwater salmon populations
in Russian Karelia. Populations clustered according their region of origin. Although temporal variation in allele frequencies
was observed in the majority of temporal comparisons, various lines of evidence demonstrated that this influence was relatively
minor compared to spatial variation that explained eight times more of the variability than temporal variation. Temporal stability
tended to occur in populations from rivers with a higher linear lake coefficient. The high level of genetic structuring observed
in both lake systems and the apparent low level of migration between populations suggests that treating each river as a separate
management unit is recommended. In addition, as the number of populations is large, the best strategy for such fine scale
management would be to ensure that the level of natural reproduction in each river is sufficient to sustain the population.
A prioritization strategy for population conservation based on estimating the relative roles of different evolutionary forces
shaping the gene pools highlighted a number of populations where further monitoring is warranted and also identified populations
which could be prioritized for conservation as living gene banks in the event that conservation resources are limited. This
prioritization agreed well with the occurrence of temporal (in)stability. 相似文献
59.
60.
Andrea Dlasková Tomáš Špaček Jitka Šantorová Lydie Plecitá-Hlavatá Zuzana Berková František Saudek Mark Lessard Joerg Bewersdorf Petr Ježek 《BBA》2010,1797(6-7):1327-1341
Insulin production in pancreatic β-cells is critically linked to mitochondrial oxidative phosphorylation. Increased ATP production triggered by blood glucose represents the β-cells' glucose sensor. Type-2 diabetes mellitus results from insulin resistance in peripheral tissues and impaired insulin secretion. Pathology of diabetic β-cells might be reflected by the altered morphology of mitochondrial network. Its characterization is however hampered by the complexity and density of the three-dimensional (3D) mitochondrial tubular networks in these cell types. Conventional confocal microscopy does not provide sufficient axial resolution to reveal the required details; electron tomography reconstruction of these dense networks is still difficult and time consuming. However, mitochondrial network morphology in fixed cells can also be studied by 4Pi microscopy, a laser scanning microscopy technique which provides an ~ 7-fold improved axial resolution (~ 100 nm) over conventional confocal microscopy. Here we present a quantitative study of these networks in insulinoma INS-1E cells and primary β-cells in Langerhans islets. The former were a stably-transfected cell line while the latter were transfected with lentivirus, both expressing mitochondrial matrix targeted redox-sensitive GFP. The mitochondrial networks and their partial disintegration and fragmentation are revealed by carefully created iso-surface plots and their quantitative analysis. We demonstrate that β-cells within the Langerhans islets from diabetic Goto Kakizaki rats exhibited a more disintegrated mitochondrial network compared to those from control Wistar rats and model insulinoma INS-1E cells. Standardization of these patterns may lead to development of morphological diagnostics for Langerhans islets, for the assessment of β-cell condition, before their transplantations. 相似文献