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Manfred?R?schEmail author Jutta?Lechterbeck 《Vegetation History and Archaeobotany》2016,25(4):339-358
A profundal core from Litzelsee, a small cirque lake in the western Lake Constance region, was investigated by pollen analysis and dated radiometrically. The upper part of the core, chronologically between 5000 cal bc and 1850 ad, was sampled continuously, resulting in a total of 449 samples, each with a sum of 1,000 arboreal pollen grains. Also in this huge data set, rare taxa, normally lacking or very scarce in pollen profiles, were registered. The ecological evaluation of these, with a focus on anthropogenic indicators, sheds light on environmental and human impact history from the Neolithic to Modern times. Further, the results are put in a regional context, together with seven other mostly unpublished pollen profiles studied in the same way. 相似文献
153.
We analyzed male migration during a 20-year period in the free-ranging Barbary macaque population of Affenberg Salem. Most natal migrations occurred around puberty, but only one third of all males left the natal group. Secondary group transfers were rare. All males immediately transferred to other bisexual groups. Migration rates were highest during periods with high adult female/male ratios within social groups. Immigrants highly preferred groups with fewer males of their own age than in the natal group, and many males immigrated into groups that had no male their own age. These groups originated from a skewed distribution of resident males during group fissions. A comparison of emigrants with their natal peers supports the inbreeding avoidance hypothesis as cause of emigration rather than the male competition avoidance hypothesis. Emigrants had no lower individual rank position and did not come from lower-ranking matrilines. Emigrants had more female maternal relatives, especially sisters. Males without female relatives almost never emigrated. Conversely, there is virtually no indication that emigrants were evicted from the natal group. Emigrants had no increased mortality. Paternity data revealed that the reproductive success of emigrants and natal males is similar, indicating that emigration had no reproductive cost. Many similarities between emigrants and natal males that separated from female maternal kin during group fissions suggest that inner migration during fissions is an alternative way to avoid maternal inbreeding. The mating system resulted in a genetic structure within social groups that largely diminished the chances for paternal inbreeding even without recognizing paternal kin. 相似文献
154.
SH3P7 Is a Cytoskeleton Adapter Protein and Is Coupled to Signal Transduction from Lymphocyte Antigen Receptors 总被引:3,自引:0,他引:3 下载免费PDF全文
Oliver Larbolette Bernd Wollscheid Jutta Schweikert Peter J. Nielsen Jürgen Wienands 《Molecular and cellular biology》1999,19(2):1539-1546
Lymphocytes respond to antigen receptor engagement with tyrosine phosphorylation of many cellular proteins, some of which have been identified and functionally characterized. Here we describe SH3P7, a novel substrate protein for Src and Syk family kinases. SH3P7 migrates in sodium dodecyl sulfate-polyacrylamide gel electrophoresis as a 55-kDa protein that is preferentially expressed in brain, thymus, and spleen. It contains multiple amino acid sequence motifs, including two consensus tyrosine phosphorylation sites of the YXXP type and one SH3 domain. A region of sequence similarity, which we named SCAD, was found in SH3P7 and three actin-binding proteins. The SCAD region may represent a new type of protein-protein interaction domain that mediates binding to actin. Consistent with this possibility, SH3P7 colocalizes with actin filaments of the cytoskeleton. Altogether, our data implicate SH3P7 as an adapter protein which links antigen receptor signaling to components of the cytoskeleton. 相似文献
155.
Lukas Habernig Filomena Broeskamp Andreas Aufschnaiter Jutta Diessl Carlotta Peselj Elisabeth Urbauer Tobias Eisenberg Ana de Ory Sabrina Büttner 《PLoS genetics》2021,17(11)
The capacity of a cell to maintain proteostasis progressively declines during aging. Virtually all age-associated neurodegenerative disorders associated with aggregation of neurotoxic proteins are linked to defects in the cellular proteostasis network, including insufficient lysosomal hydrolysis. Here, we report that proteotoxicity in yeast and Drosophila models for Parkinson’s disease can be prevented by increasing the bioavailability of Ca2+, which adjusts intracellular Ca2+ handling and boosts lysosomal proteolysis. Heterologous expression of human α-synuclein (αSyn), a protein critically linked to Parkinson’s disease, selectively increases total cellular Ca2+ content, while the levels of manganese and iron remain unchanged. Disrupted Ca2+ homeostasis results in inhibition of the lysosomal protease cathepsin D and triggers premature cellular and organismal death. External administration of Ca2+ reduces αSyn oligomerization, stimulates cathepsin D activity and in consequence restores survival, which critically depends on the Ca2+/calmodulin-dependent phosphatase calcineurin. In flies, increasing the availability of Ca2+ discloses a neuroprotective role of αSyn upon manganese overload. In sum, we establish a molecular interplay between cathepsin D and calcineurin that can be activated by Ca2+ administration to counteract αSyn proteotoxicity. 相似文献
156.
Enzyme discovery in individual strains of microorganisms is compromised by the limitations of pure culturing. In principle, metaproteomics allows for fractionation and study of different parts of the protein complement but has hitherto mainly been used to identify intracellular proteins. However, the extracellular environment is also expected to comprise a wealth of information regarding important proteins. An absolute requirement for metaproteomic studies of protein expression, and irrespective of downstream methods for analysis, is that sample preparation methods provide clean, concentrated and representative samples of the protein complement. A battery of methods for concentration, extraction, precipitation and resolubilization of proteins in the extracellular environment of a constructed microbial community was assessed by means of 2D gel electrophoresis and image analysis to elucidate whether it is possible to make the extracellular protein complement available for metaproteomic analysis. Most methods failed to provide pure samples and therefore negatively influenced protein gel migration and gel background clarity. However, one direct precipitation method (TCA-DOC/acetone) and one extraction/precipitation method (phenol/methanol) provided complementary high quality 2D gels that allowed for high spot detection ability and thereby also spot detection of less abundant extracellular proteins. 相似文献
157.
Michael Wilhelm Georg Eberwein Jürgen H?lzer Jutta Begerow Dorothee Sugiri Dieter Gladtke Ulrich Ranft 《Journal of trace elements in medicine and biology》2005,19(1):83-90
Cadmium (Cd) and lead (Pb) exposure of children and their mothers living in the vicinity of industrial sources (metal refining) was assessed by a cross-sectional study performed in 2000. Study areas were the highly industrialized city of Duisburg and a rural area of North Rhine Westphalia, Germany. Exposure to ambient air concentrations of Cd and Pb was calculated from a Lagrange dispersion model using data sets from ambient air quality measurements. Cd in blood and urine and Pb in blood were measured by AAS. Mean age (years) was 6.4 (range 5.5-7.7) for children (n = 238) and 36 (range 23-48) for mothers (n = 213). A total of 49% of the children were males. Factors suspected to influence metal levels in blood or urine were obtained by questionnaire. Individual ambient Cd and Pb levels according to the home address ranged from 0.5 ng/m3 (Cd) and 0.03 microg/m3 (Pb) (rural area) up to 31.2 ng/m3 (Cd) and 0.73 microg/m3 (Pb) (industrialized area). Cd levels (geometric mean) in blood (0.13 and 0.10 microg/L) and urine (both areas 0.09 microg/L) of children did not differ between the two areas. Cd levels in blood and urine of mothers from the industrialized area were higher (blood 0.39 microg/L, urine 0.28 microg/L) than in those from the rural area (blood 0.25 microg/L, urine 0.25 microg/L). Pb levels in the blood of children from the industrialized area were higher (31 microg/L) than in those from the rural area (21 microg/L). Pb levels in the blood of mothers did not differ between the two areas (both 24 microg/L). Pb levels in blood showed a significant association between child and mother (n = 192; r = 0.26, p < 0.001). This did not apply for Cd in blood or urine. Regression analysis clearly revealed that Pb levels in ambient air were associated with Pb in the blood of children. Minor associations were also found between Cd in air and Cd in the blood of mothers and between Cd in air and urine of mothers. 相似文献
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Newell AE Fiedler SE Ruan JM Pan J Wang PJ Deininger J Corless CL Carr DW 《Cell motility and the cytoskeleton》2008,65(7):539-552
A-kinase anchoring proteins (AKAPs) bind to protein kinase A (PKA) via an amphipathic helix domain that interacts with a dimerization/docking domain on the regulatory (R) subunit of PKA. Four other mammalian proteins (ROPN1, ASP, SP17, and CABYR) also contain a highly conserved RII dimerization/docking (R2D2) domain, suggesting all four proteins may interact with all AKAPs in a manner similar to RII. All four of these proteins were originally detected in the flagellum of mammalian sperm. In this report, we demonstrate that all four R2D2 proteins are expressed in a wide variety of tissues and three of the proteins SP17, CABYR, and ASP are located in motile cilia of human bronchus and fallopian tubes. In addition, we detect SP17 in primary cilia. We also provide evidence that ROPN1 and ASP bind to a variety of AKAPs and this interaction can be disrupted with anchoring inhibitor peptides. The interaction of SP17 and CABYR with AKAPs appears to be much more limited. None of the R2D2 proteins appears to bind cAMP, a fundamental characteristic of the regulatory subunits of PKA. These observations suggest that R2D2 proteins utilize docking interactions with AKAPs to accomplish their function of regulating cilia and flagella. Based on location, affinity for AKAPs and lack of affinity for cAMP, it appears that each R2D2 protein has a unique role in this process. 相似文献