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101.
Rune Dietz Mads Peter Heide-Jørgensen Pierre Richard Jack Orr Kristin Laidre Hans Christian Schmidt 《Polar Biology》2008,31(11):1295-1306
Twenty-one narwhals tagged in 2003 and 2004 in Admiralty Inlet showed a different summer distributional pattern than previous
narwhal-tracking studies from Somerset Island, Eclipse Sound and Melville Bay. The migration of the narwhals tracked from
Admiralty Inlet moved out through Lancaster Sound 15 days earlier (P < 0.0001) than the narwhals summering around Eclipse Sound, whereas the Admiralty Inlet narwhals reached the mouths of Eclipse
Sound 18 days later (P < 0.0001) than the Eclipse Sound summering population. The winter range of the Admiralty Inlet narwhals overlapped with the
winter range of narwhals from Melville Bay and Eclipse Sound in central southern Baffin Bay and Northern Davis Strait, but
not with the winter range of narwhals from Somerset Island that wintered further north. Distribution size of range, and population
size did not appear to be related. An example of considerable year to year variation between area of summer and winter distribution
in the 2 years was believed to be related to the sample size and number of pods of whales tagged, rather than to differences
in sex or age classes. 相似文献
102.
Impact of aeration and heme-activated respiration on Lactococcus lactis gene expression: identification of a heme-responsive operon 总被引:1,自引:0,他引:1
Pedersen MB Garrigues C Tuphile K Brun C Vido K Bennedsen M Møllgaard H Gaudu P Gruss A 《Journal of bacteriology》2008,190(14):4903-4911
Lactococcus lactis is a widely used food bacterium mainly characterized for its fermentation metabolism. However, this species undergoes a metabolic shift to respiration when heme is added to an aerobic medium. Respiration results in markedly improved biomass and survival compared to fermentation. Whole-genome microarrays were used to assess changes in L. lactis expression under aerobic and respiratory conditions compared to static growth, i.e., nonaerated. We observed the following. (i) Stress response genes were affected mainly by aerobic fermentation. This result underscores the differences between aerobic fermentation and respiration environments and confirms that respiration growth alleviates oxidative stress. (ii) Functions essential for respiratory metabolism, e.g., genes encoding cytochrome bd oxidase, menaquinone biosynthesis, and heme uptake, are similarly expressed under the three conditions. This indicates that cells are prepared for respiration once O(2) and heme become available. (iii) Expression of only 11 genes distinguishes respiration from both aerobic and static fermentation cultures. Among them, the genes comprising the putative ygfCBA operon are strongly induced by heme regardless of respiration, thus identifying the first heme-responsive operon in lactococci. We give experimental evidence that the ygfCBA genes are involved in heme homeostasis. 相似文献
103.
104.
Engell-Noerregaard L Hansen TH Andersen MH Thor Straten P Svane IM 《Cancer immunology, immunotherapy : CII》2009,58(1):1-14
During the past years numerous clinical trials have been carried out to assess the ability of dendritic cell (DC) based immunotherapy
to induce clinically relevant immune responses in patients with malignant diseases. A broad range of cancer types have been
targeted including malignant melanoma which in the disseminated stage have a very poor prognosis and only limited treatment
options with moderate effectiveness. Herein we describe the results of a focused search of recently published clinical studies
on dendritic cell vaccination in melanoma and review different vaccine parameters which are frequently claimed to have a possible
influence on clinical response. These parameters include performance status, type of antigen, DC maturation status, route
of vaccine administration, use of adjuvant, and vaccine induced immune response. In total, 38 articles found through Medline
search, have been included for analysis covering a total of 626 patients with malignant melanoma treated with DC based therapy.
Clinical response (CR, PR and SD) were found to be significantly correlated with the use of peptide antigens (p = 0.03), the use of any helper antigen/adjuvant (p = 0.002), and induction of antigen specific T cells (p = 0.0004). No significant correlations between objective response (CR and PR) and the tested parameters were found. However,
a few non-significant trends were demonstrated; these included an association between objective response and use of immature
DCs (p = 0.08), use of adjuvant (p = 0.09), and use of autologous antigen preparation (p = 0.12). The categorisation of SD in the response group is debatable. Nevertheless, when the SD group were analysed separately
we found that SD was significantly associated with use of peptide antigens (p = 0.0004), use of adjuvant (p = 0.01), and induction of antigen specific T cells (p = 0.0003). No specific route of vaccine administration showed superiority. Important lessons can be learned from previous
studies, interpretation of these findings should, however, be done with reservation for the many minor deviations in the different
treatment schedules among the published studies, which were not considered in order to be able to process and group the data. 相似文献
105.
Immunogenicity of HLA-A1-restricted peptides derived from S100A4 (metastasin 1) in melanoma patients
Valeska Hofmeister-Mueller Claudia S. Vetter-Kauczok Ramona Ullrich Katharina Meder Eugene Lukanidin Eva-Bettina Broecker Per thor Straten Mads Hald Andersen David Schrama Juergen C. Becker 《Cancer immunology, immunotherapy : CII》2009,58(8):1265-1273
S100A4 (metastasin 1) belongs to the S100 family of Ca2+ binding proteins. While not present in most differentiated adult tissues, S100A4 is upregulated in the micromilieu of tumors.
It is primarily expressed by tumor-associated macrophages, fibroblasts, and tumor endothelial cells. Due to its strong induction
in tumors S100A4 is a promising target for cancer immunotherapy. By reverse immunology, using epitope prediction programs,
we identified 3 HLA-A1-restricted peptide epitopes (S100A4 A1-1, A1-2, and A1-3) which are subject to human T cell responses
as detected in peripheral blood of melanoma patients by means of IFN-γ ELISPOT and cytotoxicity assays. In addition, IFN-γ
responses to S100A4 A1-2 can not only be induced by stimulation of T cells with peptide-loaded DC but also by stimulation
with S100A4 protein-loaded DC, indicating that this epitope is indeed generated by processing of the endogenously expressed
protein. In addition, S100A4 A1-2 reactive T cells demonstrate lysis of HLA-A1+ fibroblasts in comparison to HLA-A1− fibroblasts. In summary, this HLA-A1-restricted peptide epitope is a candidate for immunotherapeutical approaches targeting
S100A4-expressing cells in the tumor stroma. 相似文献
106.
Computer tomographic investigation of subcutaneous adipose tissue as an indicator of body composition 总被引:1,自引:0,他引:1
Fintan J McEvoy Mads T Madsen Mai B Nielsen Eiliv L Svalastoga 《Acta veterinaria Scandinavica》2009,51(1):28
Background
Modern computer tomography (CT) equipment can be used to acquire whole-body data from large animals such as pigs in minutes or less. In some circumstances, computer assisted analysis of the resulting image data can identify and measure anatomical features. The thickness of subcutaneous adipose tissue at a specific site measured by ultrasound, is used in the pig industry to assess adiposity and inform management decisions that have an impact on reproduction, food conversion performance and sow longevity. The measurement site, called "P2", is used throughout the industry. We propose that CT can be used to measure subcutaneous adipose tissue thickness and identify novel measurement sites that can be used as predictors of general adiposity. 相似文献107.
Revesz L Blum E Di Padova FE Buhl T Feifel R Gram H Hiestand P Manning U Neumann U Rucklin G 《Bioorganic & medicinal chemistry letters》2006,16(2):262-266
A test library with three novel p38alpha inhibitory scaffolds and a narrow set of substituents was prepared. Appropriate combination of substituent and scaffold generated potent p38alpha inhibitors, for example, pyrazolo[3,4-b]pyridine 9, pyrazolo[3,4-d]pyrimidine 18a and pyrazolo[3,4-b]pyrazine 23b with potent in vivo activity upon oral administration in animal models of rheumatoid arthritis. 相似文献
108.
Buhl J Gautrais J Louis Deneubourg J Kuntz P Theraulaz G 《Journal of theoretical biology》2006,243(3):287-298
Many biological networks grow under strong spatial constraints, where the large-scale structure emerges from the extension, the branching and intersection of growing parts of the network. One example is provided by ant tunnelling networks, which represent the most common nest architecture in ants. Our goal was to understand how these network structures emerge from the tunnel growth dynamics. We used a standardized two-dimensional set-up shaped as a disk and studied the characteristics of tunnel growth in terms of initiation, propagation and termination of new digging sites and found that they can be described with simple probabilistic laws. We show that a model based on these simple laws and for which parameters were measured from the sand disks experiments can account for the emergence of several topological properties that were observed in experimental networks. In particular, the model accurately reproduced an allometric relation between the number of edges and the number of nodes, as well as an invariance of the node degree distribution. The model was then used to make predictions about the resulting networks' topology when the geometry of the sand substrate was shaped as a square. Experiments aimed at testing the model's predictions showed that the predictions were indeed validated. Both in the model and in the experiments, there was a similar trend for the node degree distribution tail to be steeper in the square sand patch than in the disk sand patch, while other characteristics such as the meshedness (i.e. how densely the network is internally connected) remained constant. Because network growth based on branching/fusion events is widespread in biological systems, this general model might provide useful insights for the study of other systems and, more generally, the evolution of spatial networks in biological systems. 相似文献
109.
Dres Damgaard Mads Emil Bjørn Peter Østrup Jensen Claus Henrik Nielsen 《Journal of enzyme inhibition and medicinal chemistry》2017,32(1):1203-1208
Protein citrullination catalysed by peptidylarginine deiminase (PAD) may play an important pathogenic role in several chronic inflammatory diseases and malignancies. PAD2, PAD4, and citrullinated proteins are found in the synovium of rheumatoid arthritis patients. PAD activity is dependent on calcium and reducing conditions. However, reactive oxygen species (ROS) have been shown to induce citrullination of histones in granulocytes. Here we examine the ability of H2O2 and leukocyte-derived ROS to regulate PAD activity using citrullination of fibrinogen as read-out. H2O2 at concentrations above 40?µM inhibited the catalytic activity of PAD2 and PAD4 in a dose-dependent manner. PMA-stimulated leukocytes citrullinated fibrinogen and this citrullination was markedly enhanced when ROS formation was inhibited by the NADPH oxidase inhibitor diphenyleneiodonium (DPI). In contrast, PAD released from stimulated leukocytes was unaffected by exogenously added H2O2 at concentrations up to 1000?µM. The role of ROS in regulating PAD activity may play an important part in preventing hypercitrullination of proteins. 相似文献
110.
The partitioning of the wasp venom peptide mastoparan-X (MPX) into neutral and negatively charged lipid membranes has been compared with two new synthetic analogs of MPX where the Nα-terminal of MPX was acylated with propanoic acid (PA) and octanoic acid (OA). The acylation caused a considerable change in the membrane partitioning properties of MPX and it was found that the shorter acylation with PA gave improved affinity and selectivity toward negatively charged membranes, whereas OA decreased the selectivity. Based on these findings, we hypothesize that minor differences in the embedding and positioning of the peptide in the membrane caused by either PA or OA acylation play a critical role in the fine-tuning of the effective charge of the peptide and thereby the fine-tuning of the peptide's selectivity between neutral and negatively charged lipid membranes. This finding is unique compared to previous reports where peptide acylation enhanced membrane affinity but also resulted in impaired selectivity. Our result may provide a method of enhancing selectivity of antimicrobial peptides toward bacterial membranes due to their high negative charge—a finding that should be investigated for other, more potent antimicrobial peptides in future studies. 相似文献