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171.
AG. van Ginkel BJ. Sorgdrager M. A. de Graaf I. Karalis N. Ajmone Marsan 《Netherlands heart journal》2014,22(2):77-79
We report a case of an allergic reaction after the administration of an echocardiographic contrast agent which resulted in ST-segment elevation. Hypersensitivity and allergic reactions are known causes of acute cardiovascular events. However, only limited reports are available which suggest the exact mechanism of the occurrence of angina or myocardial infarction during severe allergic reactions. In our case, through invasive imaging (coronary angiography and IVUS) we have shown for the first time a transient coronary spasm in the absence of intra-coronary thrombus and only minimal neointimal hyperplasia. 相似文献
172.
Cell membranes are phospholipid bilayers with a large number of embedded transmembrane proteins. Some of these proteins, such as scramblases, have properties that facilitate lipid flip-flop from one membrane leaflet to another. Scramblases and similar transmembrane proteins could also affect the translocation of other amphiphilic molecules, including cell-penetrating or antimicrobial peptides. We studied the effect of transmembrane proteins on the translocation of amphiphilic peptides through the membrane. Using two very different models, we consistently demonstrate that transmembrane proteins with a hydrophilic patch enhance the translocation of amphiphilic peptides by stabilizing the peptide in the membrane. Moreover, there is an optimum amphiphilicity because the peptide could become overstabilized in the transmembrane state, in which the peptide-protein dissociation is hampered, limiting the peptide translocation. The presence of scramblases and other proteins with similar properties could be exploited for more efficient transport into cells. The described principles could also be utilized in the design of a drug-delivery system by the addition of a translocation-enhancing peptide that would integrate into the membrane. 相似文献
173.
Adelmo L Cechin Marialva Sinigaglia Ney Lemke Sérgio Echeverrigaray Odalys G Cabrera Gonçalo AG Pereira José CM Mombach 《BMC plant biology》2008,8(1):50
Background
NEP1-like proteins (NLPs) are a novel family of microbial elicitors of plant necrosis. Some NLPs induce a hypersensitive-like response in dicot plants though the basis for this response remains unclear. In addition, the spatial structure and the role of these highly conserved proteins are not known. 相似文献174.
Protein content, total and specific peroxidase activity and isoperoxidase patterns were determined in crude protein preparations
from individual parts of field-grown wheat (Triticum aestivum L., cv. Jubilar). Protein content in roots, leaves, and stalks increased at the beginning of ontogenesis and then decreased
from 6th, 9th, and 10th development phase (according to Feekes), respectively. Steady increase of the protein content in the
ears was observed.
Highest peroxidase activity was found in the roots; it diminished from the onset of ontogenesis till maturity of the plants.
In the leaves and stalks a slight decrease of peroxidase activity till the 10th development phase and then an increase till
maturity was found. The ears exhibited a gradual increase of peroxidase activity. The course of specific peroxidase activity
was found to be very similar to that of total activity.
Isoperoxidase patterns did not change significantly. In the leaves, a decrease of activity of C4 and C5 isoperoxidases was recorded. In the stalks, C l isoenzyme emerged at the end of ontogenesis. A gradual increase of A1 and A5 isoperoxidase intensity took place both in the leaves and stalks. 相似文献
175.
176.
177.
To analyse the relationship between spawning migrations and flow, cyprinids from ten fish ladders of the Elbe River (Czech
Republic) were collected during the period of spawning migrations (April–June) in 1996, 2000 and 2001. Number of species and
individuals in the fish ladders increased with increasing flow up to medium values, followed by further decrease during high
flows, whilst length of individuals increased with increasing flow. Moreover, occurrence of four the most numerous species
(bleak, roach, silver bream and barbel) showed species specific differences in response to flow variability. In early spring,
the highest number of bleak in fish ladders occurred during the low flow, whilst later increased with increasing flow. Occurrence
of roach and silver bream achieved the maximum during the medium flow values across the whole studied period. In opposite,
occurrence of barbel increased with increasing flows during the whole period. Furthermore, it can be assumed that occurrence
of fish in ladders was associated not only with spawning migrations but also reflected shifts in local fish distribution in
response to flow variability in the main channel. 相似文献
178.
Industrial biotechnology employs the controlled use of microorganisms for the production of synthetic chemicals or simple
biomass that can further be used in a diverse array of applications that span the pharmaceutical, chemical and nutraceutical
industries. Recent advances in metagenomics and in the incorporation of entire biosynthetic pathways into Saccharomyces cerevisiae have greatly expanded both the fitness and the repertoire of biochemicals that can be synthesized from this popular microorganism.
Further, the availability of the S. cerevisiae entire genome sequence allows the application of systems biology approaches for improving its enormous biosynthetic potential.
In this review, we will describe some of the efforts on using S. cerevisiae as a cell factory for the biosynthesis of high-value natural products that belong to the families of isoprenoids, flavonoids
and long chain polyunsaturated fatty acids. As natural products are increasingly becoming the center of attention of the pharmaceutical
and nutraceutical industries, the use of S. cerevisiae for their production is only expected to expand in the future, further allowing the biosynthesis of novel molecular structures
with unique properties. 相似文献