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101.
102.
Britta U Goldmann Robert H Christenson Christian W Hamm Thomas Meinertz EMagnus Ohman 《Trials》2001,2(2):75-10
During the past decade considerable research has been conducted into the use of cardiac troponins, their diagnostic capability and their potential to allow risk stratification in patients with acute chest pain. Determination of risk in patients with suspected myocardial ischaemia is known to be as important as retrospective confirmation of a diagnosis of myocardial infarction (MI). Therefore, creatine kinase (CK)-MB - the former 'gold standard' in detecting myocardial necrosis - has been supplanted by new, more accurate biomarkers.Measurement of cardiac troponin levels constitute a substantial determinant in assessment of ischaemic heart disease, the presentations of which range from silent ischaemia to acute MI. Under these conditions, troponin release is regarded as surrogate marker of thrombus formation and peripheral embolization, and therefore new therapeutic strategies are focusing on potent antithrombotic regimens to improve long-term outcomes. Although elevated troponin levels are highly sensitive and specific indicators of myocardial damage, they are not always reflective of acute ischaemic coronary artery disease; other processes have been identified that cause elevations in these biomarkers. However, because prognosis appears to be related to the presence of troponins regardless of the mechanism of myocardial damage, clinicians increasingly rely on troponin assays when formulating individual therapeutic plans. 相似文献
103.
104.
Mal de Meleda (MDM) caused by mutations in the gene for SLURP-1 in patients from Germany,Turkey, Palestine,and the United Arab Emirates 总被引:7,自引:0,他引:7
Eckl KM Stevens HP Lestringant GG Westenberger-Treumann M Traupe H Hinz B Frossard PM Stadler R Leigh IM Nürnberg P Reis A Hennies HC 《Human genetics》2003,112(1):50-56
Mal de Meleda (MDM) or keratosis palmoplantaris transgrediens of Siemens is an autosomal recessive skin disorder characterized by diffuse palmoplantar keratoderma (PPK) and transgressive keratosis with an onset in early infancy. There is no associated involvement of other organs; however, a spectrum of clinical presentations with optional and variable features has been described. Mutations in the ARS (component B)-81/s gene ( LY6LS) on chromosome 8q24-qter, which encodes SLURP-1, have recently been identified in patients with MDM. Here, we have analyzed four MDM families for mutations in SLURP-1. In a large Palestinian pedigree with multiple consanguinity, patients are homozygous for a new mutation that substitutes an arginine for a conserved glycine residue at position 86. A different mutation in Turkish patients results in the same amino acid exchange. Some remarkable similarities are seen in the clinical picture of patients from both families. Patients of an Emirati Bedouin family have a homozygous alteration of the translation initiation codon. In a German family with no known consanguinity, we have shown pseudodominant inheritance. Three affected children and their affected mother are homozygous for the missense mutation W15R. Our findings indicate that the MDM type of transgressive PPK is caused by SLURP-1 mutations in patients from various origins and demonstrate allelic heterogeneity for mutations in SLURP-1. 相似文献
105.
Patricia Kreis Michiel T. van Diepen Britta J. Eickholt 《Advances in enzyme regulation》2010,50(1):119-124
Our understanding of the function and regulation of the PTEN phosphatase now extends far beyond its initial characterization as a tumor suppressor with an important role in nervous system development and function. A number of developmental neurological disorders, which harbor mutations in PTEN or the PI3K pathway, are associated with increases in neuronal cell size (i.e., specific forms of autism or tuberous sclerosis). In light of this, the discovery of a myosin-based transport mechanism offers a new outlook in exploring further the underlying mechanisms of cell size control and its consequences to nervous system function. Overall, dysregulation of the PTEN:MyosinV interaction may provide an additional signaling intersection which increases the growth potential of a number of cell types. Indeed, members of the MyosinV family are widely expressed in different combinations in tissues (Rodriguez and Cheney, 2002), and have been shown to be differentially regulated in various cancers. 相似文献
106.
107.
Rita-Eva Varga Mukhran Khundadze Markus Damme Sandor Nietzsche Birgit Hoffmann Tobias Stauber Nicole Koch J. Christopher Hennings Patricia Franzka Antje K. Huebner Michael M. Kessels Christoph Biskup Thomas J. Jentsch Britta Qualmann Thomas Braulke Ingo Kurth Christian Beetz Christian A. Hübner 《PLoS genetics》2015,11(8)
Hereditary spastic paraplegia (HSP) is characterized by a dying back degeneration of corticospinal axons which leads to progressive weakness and spasticity of the legs. SPG11 is the most common autosomal-recessive form of HSPs and is caused by mutations in SPG11. A recent in vitro study suggested that Spatacsin, the respective gene product, is needed for the recycling of lysosomes from autolysosomes, a process known as autophagic lysosome reformation. The relevance of this observation for hereditary spastic paraplegia, however, has remained unclear. Here, we report that disruption of Spatacsin in mice indeed causes hereditary spastic paraplegia-like phenotypes with loss of cortical neurons and Purkinje cells. Degenerating neurons accumulate autofluorescent material, which stains for the lysosomal protein Lamp1 and for p62, a marker of substrate destined to be degraded by autophagy, and hence appears to be related to autolysosomes. Supporting a more generalized defect of autophagy, levels of lipidated LC3 are increased in Spatacsin knockout mouse embryonic fibrobasts (MEFs). Though distinct parameters of lysosomal function like processing of cathepsin D and lysosomal pH are preserved, lysosome numbers are reduced in knockout MEFs and the recovery of lysosomes during sustained starvation impaired consistent with a defect of autophagic lysosome reformation. Because lysosomes are reduced in cortical neurons and Purkinje cells in vivo, we propose that the decreased number of lysosomes available for fusion with autophagosomes impairs autolysosomal clearance, results in the accumulation of undegraded material and finally causes death of particularly sensitive neurons like cortical motoneurons and Purkinje cells in knockout mice. 相似文献
108.
109.
Britta Gribsholt Eric Struyf Anton Tramper Maria G. I. Andersson Natacha Brion Loreto De Brabandere Stefan Van Damme Patrick Meire Jack J. Middelburg Frank Dehairs Henricus T. S. Boschker 《Biogeochemistry》2006,80(3):289-298
The fate and transport of watershed-derived ammonium in a tidal freshwater marsh fringing the nutrient rich Scheldt River,
Belgium, was quantified in a whole ecosystem 15N labeling experiment. In late summer (September) we added 15N-NH4+ to the flood water entering a 3477 m2 tidal freshwater marsh area, and traced the ammonium processing and retention in four subsequent tide cycles. In this paper
we present the results for the water-phase components of the marsh system and compare them to a similar experiment conducted
in spring/early summer (May). Changes in concentration and isotopic enrichment of NO3− + NO2−, N2O, N2, NH4+ and suspended particulate nitrogen (SPN) were measured in concert with a mass balance study. All analyzed N-pools were labeled,
and 49% of the added 15NH4+ was retained or transformed. The most important pool for 15N was nitrate, accounting for 17% of 15N-transformation. N2, N2O and SPN accounted for 2.4, 0.02 and 1.4%, respectively. The temporal and spatial patterns of 15N transformation in the water phase component of the system were remarkably similar to those observed in May, indicating good
reproducibility of the whole ecosystem labeling approach, but the absolute ammonium transformation rate was 3 times higher
in May. While the marsh surface area was crucial for nitrification in May this was less pronounced in September. Denitrification,
on the other hand, appeared more important in September compared to May. 相似文献
110.
Miguel Quintana Peter Lindell Samir K Saha Francesca del Furia Britta Lind Satish Govind Lars-Åke Brodin 《Cardiovascular ultrasound》2005,3(1):1-12