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101.
S. Typhimurium is one of the 2 most common salmonella serotypes causing human salmonellosis in Denmark. In order to illustrate the significance of different production animals as a source of infection, 1461 isolates were characterized by phage typing. The isolates originated from human patients and from cattle, pigs and poultry. By phage typing the isolates could be separated in 35 different phage types. Five types (10, 12, 66, 110 and 135) predominated and comprised 78.8% of the isolates. In humans, 57.3% of the isolates were phage type 12. This phage type was also predominant in pig herds and, to a lesser degree, in cattle. Phage types 110, 120, 135 and 193 constituted 86.5% of the poultry isolates while these phage types only made up 12.9% of the human isolates. The investigation showed that pigs are probably a major source of S. Typhimurium infection in humans in Denmark today. 相似文献
102.
The IkappaB kinase complex and NF-kappaB act as master regulators of lipopolysaccharide-induced gene expression and control subordinate activation of AP-1 总被引:4,自引:0,他引:4 下载免费PDF全文
Krappmann D Wegener E Sunami Y Esen M Thiel A Mordmuller B Scheidereit C 《Molecular and cellular biology》2004,24(14):6488-6500
103.
Voltage dependence of L-arginine transport by hCAT-2A and hCAT-2B expressed in oocytes from Xenopus laevis 总被引:1,自引:0,他引:1
Nawrath H Wegener JW Rupp J Habermeier A Closs EI 《American journal of physiology. Cell physiology》2000,279(5):C1336-C1344
Membrane potential and currents were investigated with thetwo-electrode voltage-clamp technique in Xenopus laevisoocytes expressing hCAT-2A or hCAT-2B, the splice variants of the human cationic amino acid transporter hCAT-2. Both hCAT-2A- andhCAT-2B-expressing oocytes exhibited a negative extracellularL-arginine concentration ([L-Arg]o)-sensitive membrane potential,additive to the K+ diffusion potential, when cells wereincubated in Leibovitz medium (containing 1.45 mM L-Arg and0.25 mM L-lysine). The two carrier proteins produced inwardand outward currents, which were dependent on the L-Arggradient and membrane potential. Ion substitution experiments showedthat the hCAT-induced currents were independent of externalNa+, K+, Ca2+, or Mg2+.The apparent Michaelis-Menten constant values at 60 mV, obtained fromplots of L-Arg-induced currents against[L-Arg]o, were 0.97 and 0.13 mM in oocytesexpressing hCAT-2A and hCAT-2B, respectively; maximal currentsamounted to 194 ± 8 and 84 ± 2 nA, respectively. Atsaturating [L-Arg]o, the current-voltagerelationships of hCAT-2A-expressing oocytes became steeper, yielding anadditional conductance up to 2 µS/oocyte, whereas those ofhCAT-2B-expressing oocytes were simply shifted to the right, resultingin voltage-independent difference currents. The distinctelectrochemical properties of the two isoforms of hCAT-2 are assumed tocontribute differentially to the membrane transport and the maintenanceof cationic amino acids in various tissues. 相似文献
104.
Sensory rhodopsin II (also called phoborhodopsin) from the archaeal Natronobacterium pharaonis (pSRII) functions as a repellent phototaxis receptor. The excitation of the receptor by light triggers the activation of a transducer molecule (pHtrII) which has close resemblance to the cytoplasmic domain of bacterial chemotaxis receptors. In order to elucidate the first step of the signal transduction chain, the accessibility as well as static and transient mobility of cytoplasmic residues in helices F and G were analysed by electron paramagnetic resonance spectroscopy. The results indicate an outward tilting of helix F during the early steps of the photocycle which is sustained until the reformation of the initial ground state. Co-expression of pSRII with a truncated fragment of pHtrII affects the accessibility and/or the mobility of certain spin-labelled residues on helices F and G. The results suggest that these sites are located within the binding surface of the photoreceptor with its transducer. 相似文献
105.
Five different two-parameter models were fitted to published data from 30 studies to identify an approximate mathematical form of the relationship between fertility in cattle and the number of inseminated spermatozoa. In all cases, the first parameter defines the maximum attainable fertility, and the second scales the dose according to the percentage of the maximum attained. The best model was the hyperbolic dose-response curve used in pharmacology to analyse the effect of drugs. There is evidence that the semen of individual bulls differs in both parameters of the models and that therefore the viability of semen may be multidimensional. This might explain why measures of semen quality have hitherto been found to correlate poorly with fertility. The hypothesis that spermatozoa are subject to the law of mass action at the ovum predicts these and some other aspects of fertility, and indicates that heterospermic inseminations may provide an efficient way of estimating the parameters of semen. 相似文献
106.
Himmelreich U Weber R Ramos-Cabrer P Wegener S Kandal K Shapiro EM Koretsky AP Hoehn M 《Molecular imaging》2005,4(2):104-109
In vivo monitoring of cells labeled with paramagnetic iron oxide particles by magnetic resonance imaging (MRI) is complicated by intrinsic contrast of blood vessels. Distinction between T2* effects caused by blood vessels from those caused by labeled cells was so far only possible after carefully following the location of hypointense regions through subsequent slices of T2*-weighted 3-D MRI datasets, a procedure that is time consuming and not always reliable in the case of smaller blood vessels. Here, we demonstrate that the modification of the inhalation gas mixture from the routinely used composition 35% O2 and 65% N2O to a mixture containing 95% O2 and 5% CO2 results in a contrast suppression of most small blood vessels and reduces the intrinsic T2* effect of large vessels dramatically in an animal model. This change in protocol of physiological conditions was well tolerated by all studied animals, even over prolonged experimental times. The changed inhalation gas mixture thus provides a more reliable identification method for small clusters of iron oxide labeled cells in vivo. 相似文献
107.
Life cycle assessment of Australian sugarcane production with a focus on sugarcane growing 总被引:1,自引:0,他引:1
Marguerite Anne Renouf Malcolm K. Wegener Robert J. Pagan 《The International Journal of Life Cycle Assessment》2010,15(9):927-937
Purpose
Past life cycle assessments (LCA) of sugarcane (Saccharum officinarum) production have commonly been based on limited datasets, and variability has not been well described. In this work, Australian sugarcane production was assessed more comprehensively in order to generate a robust set of LCA results for use in subsequent assessments of sugarcane products and also to investigate: (1) variability due to regional differences, (2) factors influencing variability, and (3) significance of the impacts. 相似文献108.
Thomas Grochtdreis Christian Brettschneider Annemarie Wegener Birgit Watzke Steffi Riedel-Heller Martin H?rter Hans-Helmut K?nig 《PloS one》2015,10(5)
BackgroundFor the treatment of depressive disorders, the framework of collaborative care has been recommended, which showed improved outcomes in the primary care sector. Yet, an earlier literature review did not find sufficient evidence to draw robust conclusions on the cost-effectiveness of collaborative care.PurposeTo systematically review studies on the cost-effectiveness of collaborative care, compared with usual care for the treatment of patients with depressive disorders in primary care.MethodsA systematic literature search in major databases was conducted. Risk of bias was assessed using the Cochrane Collaboration’s tool. Methodological quality of the articles was assessed using the Consensus on Health Economic Criteria (CHEC) list. To ensure comparability across studies, cost data were inflated to the year 2012 using country-specific gross domestic product inflation rates, and were adjusted to international dollars using purchasing power parities (PPP).ResultsIn total, 19 cost-effectiveness analyses were reviewed. The included studies had sample sizes between n = 65 to n = 1,801, and time horizons between six to 24 months. Between 42% and 89% of the CHEC quality criteria were fulfilled, and in only one study no risk of bias was identified. A societal perspective was used by five studies. Incremental costs per depression-free day ranged from dominance to US$PPP 64.89, and incremental costs per QALY from dominance to US$PPP 874,562.ConclusionDespite our review improved the comparability of study results, cost-effectiveness of collaborative care compared with usual care for the treatment of patients with depressive disorders in primary care is ambiguous depending on willingness to pay. A still considerable uncertainty, due to inconsistent methodological quality and results among included studies, suggests further cost-effectiveness analyses using QALYs as effect measures and a time horizon of at least 1 year. 相似文献
109.
Long,Processive Enzymatic DNA Synthesis Using 100% Dye-Labeled Terminal Phosphate-Linked Nucleotides
Jonas Korlach Arek Bibillo Jeffrey Wegener Paul Peluso Thang T. Pham Insil Park 《Nucleosides, nucleotides & nucleic acids》2013,32(9):1072-1082
We demonstrate the efficient synthesis of DNA with complete replacement of the four deoxyribonucleoside triphosphate (dNTP) substrates with nucleotides carrying fluorescent labels. A different, spectrally separable fluorescent dye suitable for single molecule fluorescence detection was conjugated to each of the four dNTPs via linkage to the terminal phosphate. Using these modified nucleotides, DNA synthesis by φ29 DNA polymerase was observed to be processive for products thousands of bases in length, with labeled nucleotide affinities and DNA polymerization rates approaching unmodified dNTP levels. Results presented here show the compatibility of these nucleotides for single-molecule, real-time DNA sequencing applications. 相似文献
110.