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41.

Objective

There is a general agreement that physical pain serves as an alarm signal for the prevention of and reaction to physical harm. It has recently been hypothesized that “social pain,” as induced by social rejection or abandonment, may rely on comparable, phylogenetically old brain structures. As plausible as this theory may sound, scientific evidence for this idea is sparse. This study therefore attempts to link both types of pain directly. We studied patients with borderline personality disorder (BPD) because BPD is characterized by opposing alterations in physical and social pain; hyposensitivity to physical pain is associated with hypersensitivity to social pain, as indicated by an enhanced rejection sensitivity.

Method

Twenty unmedicated female BPD patients and 20 healthy participants (HC, matched for age and education) played a virtual ball-tossing game (cyberball), with the conditions for exclusion, inclusion, and a control condition with predefined game rules. Each cyberball block was followed by a temperature stimulus (with a subjective pain intensity of 60% in half the cases). The cerebral responses were measured by functional magnetic resonance imaging. The Adult Rejection Sensitivity Questionnaire was used to assess rejection sensitivity.

Results

Higher temperature heat stimuli had to be applied to BPD patients relative to HCs to reach a comparable subjective experience of painfulness in both groups, which suggested a general hyposensitivity to pain in BPD patients. Social exclusion led to a subjectively reported hypersensitivity to physical pain in both groups that was accompanied by an enhanced activation in the anterior insula and the thalamus. In BPD, physical pain processing after exclusion was additionally linked to enhanced posterior insula activation. After inclusion, BPD patients showed reduced amygdala activation during pain in comparison with HC. In BPD patients, higher rejection sensitivity was associated with lower activation differences during pain processing following social exclusion and inclusion in the insula and in the amygdala.

Discussion

Despite the similar behavioral effects in both groups, BPD patients differed from HC in their neural processing of physical pain depending on the preceding social situation. Rejection sensitivity further modulated the impact of social exclusion on neural pain processing in BPD, but not in healthy controls.  相似文献   
42.
Thymic development of αβ T lymphocytes into invariant natural killer (NK) T cells depends on their selection via agonistic lipid antigen presented by CD1d. If successful, newly selected NKT cells gain effector functions already in the thymus. Some γδ T cell subsets also acquire effector functions in the thymus. However, it is not clear whether agonistic TCR stimulation is involved in thymic γδ T cell selection and development. Here we combine two genetic models to address this question. MiR-181a/b-1–/–mice, which show impaired agonistic T cell selection of invariant αβ NKT cells, were crossed to Tcrd-H2BeGFP reporter mice to monitor selection, intra-thymic expansion and differentiation of γδ T cells. We found that miR-181a/b-1-deficiency had no effect on numbers of thymic γδ T cell or on their differentiation towards an IL-17- or IFN-γ-producing effector phenotype. Also, the composition of peripheral lymph node γδ T cells was not affected by miR-181a/b-1-deficiency. Dendritic epidermal γδ T cells were normally present in knock-out animals. However, we observed elevated frequencies and numbers of γδ NKT cells in the liver, possibly because γδ NKT cells can expand and replace missing αβ NKT cells in peripheral niches. In summary, we investigated the role of miR-181a/b-1 for selection, intrathymic development and homeostasis of γδ T cells. We conclude that miR-181a/b-1-dependent modulation of T cell selection is not critically required for innate development of γδ NKT cells or of any other γδ T cell subtypes.  相似文献   
43.
The applications of traditional morphological and molecular methods for species identification are greatly restricted by processing speed and on a regional or greater scale are generally considered unfeasible. In this context, high-throughput sequencing, or metagenetics, has been proposed as an efficient tool to document biodiversity. Here we evaluated the effectiveness of 454 pyrosequencing in marine metazoan community analysis using the 18S rDNA: V1-V2 region. Multiplex pyrosequencing of the V1-V2 region was used to analyze two pooled samples of DNA, one comprising 118 and the other 37 morphologically identified species, and one natural sample taken directly from a North Sea zooplankton community. A DNA reference library comprising all species represented in the pooled samples was created by Sanger sequencing, and this was then used to determine the optimal similarity threshold for species delineation. The optimal threshold was found at 99% species similarity, with 85% identification success. Pyrosequencing was able to identify between fewer species: 67% and 78% of the species in the two pooled samples. Also, a large number of sequences for three species that were not included in the pooled samples were amplified by pyrosequencing, suggesting preferential amplification of some genotypes and the sensitivity of this approach to even low levels of contamination. Conversely, metagenetic analysis of the natural zooplankton sample identified many more species (particularly gelatinous zooplankton and meroplankton) than morphological analysis of a formalin-fixed sample from the same sampling site, suggesting an increased level of taxonomic resolution with pyrosequencing. The study demonstrated that, based on the V1-V2 region, 454 sequencing does not provide accurate species differentiation and reliable taxonomic classification, as it is required in most biodiversity monitoring. The analysis of artificially prepared samples indicated that species detection in pyrosequencing datasets is complicated by potential PCR-based biases and that the V1-V2 marker is poorly resolved for some taxa.  相似文献   
44.
The genomic analysis of Streptococcus pneumoniae strains identified the Pneumococcal adherence and virulence factor B (PavB), whose repetitive sequences, designated Streptococcal Surface REpeats (SSURE), interact with human fibronectin. Here, we showed the gene in all tested pneumococci and identified that the observed differences in the molecular mass of PavB rely on the number of repeats, ranging from five to nine SSURE. PavB interacted with fibronectin and plasminogen in a dose‐dependent manner as shown by using various SSURE peptides. In addition, we identified PavB as colonization factor. Mice infected intranasally with ΔpavB pneumococci showed significantly increased survival times compared with wild‐type bacteria. Importantly, the pavB‐mutant showed a delay in transmigration to the lungs as observed in real‐time using bioluminescent pneumococci and decreased colonization rates in a nasopharyngeal carriage model. In co‐infection experiments the wild‐type out‐competed the pavB‐mutant and infections of epithelial cells demonstrated that PavB contributes to adherence to host cell. Blocking experiments suggested a function of PavB as adhesin, which was confirmed by direct binding of SSURE peptides to host cells. Finally, PavB may represent a new vaccine candidate as SSURE peptides reacted with human sera. Taken together, PavB is a surface‐exposed adhesin, which contributes to pneumococcal colonization and infections of the respiratory airways.  相似文献   
45.
The barley proteins have been the subject of interests of many research groups dealing with barley grains, malt and beer. The proteins which remain intact after harsh malting conditions influence the quality and flavor of beer. The characteristic feature of the proteins present in malt and beer is their extensive modification with carbohydrates, mainly glucose that comes from the starch degradation during technological processes. The degree of the protein glycation has an effect on the quality of malt and beer and on the properties of the beer foam. A combination of two-dimensional high performance liquid chromatography (2D-HPLC) and matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF/TOF MS) was used for the analysis of the protein extracts that were reduced, alkylated, and degraded enzymatically without prior protein separation. This so-called "shot-gun" approach enabled us to determine glycation sites in one third of the proteins identified in the study and to propose potential glycation markers for fast and efficient monitoring during malting.  相似文献   
46.
  1. When searching for food, great tits (Parus major) can use herbivore‐induced plant volatiles (HIPVs) as an indicator of arthropod presence. Their ability to detect HIPVs was shown to be learned, and not innate, yet the flexibility and generalization of learning remain unclear.
  2. We studied if, and if so how, naïve and trained great tits (Parus major) discriminate between herbivore‐induced and noninduced saplings of Scotch elm (Ulmus glabra) and cattley guava (Psidium cattleyanum). We chemically analyzed the used plants and showed that their HIPVs differed significantly and overlapped only in a few compounds.
  3. Birds trained to discriminate between herbivore‐induced and noninduced saplings preferred the herbivore‐induced saplings of the plant species they were trained to. Naïve birds did not show any preferences. Our results indicate that the attraction of great tits to herbivore‐induced plants is not innate, rather it is a skill that can be acquired through learning, one tree species at a time.
  4. We demonstrate that the ability to learn to associate HIPVs with food reward is flexible, expressed to both tested plant species, even if the plant species has not coevolved with the bird species (i.e., guava). Our results imply that the birds are not capable of generalizing HIPVs among tree species but suggest that they either learn to detect individual compounds or associate whole bouquets with food rewards.
  相似文献   
47.
Atmospheric deposition is an important nutrient input to forests. The chemical composition of the rainfall is altered by the forest canopy due to interception and canopy exchange. Bulk deposition and stand deposition (throughfall plus stemflow) of Na+, Cl?, K+, Ca2+, Mg2+, PO 4 3? , SO 4 2? , H+, Mn2+, Al3+, Fe2+, NH 4 + , NO 3 ? and Norg were measured in nine deciduous forest plots with different tree species diversity in central Germany. Interception deposition and canopy exchange rates were calculated with a canopy budget model. The investigated forest plots were pure beech (Fagus sylvatica L.) plots, three-species plots (Fagus sylvatica, Tilia cordata Mill. or T. platyphyllos Scop. and Fraxinus excelsior L.) and five-species plots (Fagus sylvatica, T. cordata or T. platyphyllos, Fraxinus excelsior, Acer platanoides L., A. pseudoplatanus L. or A. campestre L. and Carpinus betulus L.). The interception deposition of all ions was highest in pure beech plots and was negatively related to the Shannon index. The stand deposition of K+, Ca2+, Mg2+ and PO 4 3? was higher in mixed species plots than in pure beech plots due to higher canopy leaching rates in the mixed species plots. The acid input to the canopy and to the soil was higher in pure beech plots than in mixed species plots. The high canopy leaching rates of Mn2+ in pure beech plots indicated differences in soil properties between the plot types. Indeed, pH, effective cation exchange capacity and base saturation were lower in pure beech plots. This may have contributed to the lower leaching rates of K+, Ca2+ and Mg2+ compared to the mixed species plots. However, foliar analyses indicated differences in the ion status among the tree species, which may additionally have influenced canopy exchange. In conclusion, the nutrient input to the soil resulting from deposition and canopy leaching was higher in mixed species plots than in pure beech plots, whereas the acid input was highest in pure beech plots.  相似文献   
48.
The purpose of this study was to analyse body size of Lithuanian newborns born in 1998 and 2004, and to compare results with the data from 1974. The main body size measurements - body weight, body length and body mass index (BMI) of 3281 (1705 boys and 1576 girls) live term singleton Lithuanian newborns' were analysed according to gestational age, sex and health status. The data were collected in the Clinic of Obstetrics and Gynaecology of Vilnius University (VU COG), and the comparison with the data of Lithuanian Medical Birth Register of (LMBR) was performed. No significant differences between height, weight and body mass index in 1998 and the same characteristics in 2004 were observed. Means and principal percentiles (10th, 50th, 90th) of body measurements of 37-42 weeks of gestational age newborns were obtained. The mean body length was 52.8/52.19 cm (boys/girls), body weight--3589/3454 g, BMI 12.82/12.64 correspondingly. The recent data were compared with the similar data from 1974 cohort. Statistically significant increment of body length of Lithuanian newborns was observed in all age and sex groups, whereas weight changes were less evident. The analysis of BMI demonstrated the following trend: newborns became longer, but not relatively heavier in comparison with the similar data 30 years ago. Hence, it is important to evaluate weight changes of neonate in relation with the changes in height. Further investigation of prevalence of neonatal macrosomia, possible factors of body size changes, their relationship to general health status and further health issues of the child should be explored.  相似文献   
49.
Gnomonia fragariae is a poorly studied ascomycete belonging to Diaporthales. Originally G. fragariae was considered a saprophyte occurring on dead tissues of strawberry plants. Recently this fungus was found in Latvia and Sweden, and it was proven to be the cause of severe root rot and petiole blight of strawberry. Thirteen isolates of this pathogen and several other Gnomonia species occurring on rosaceous hosts were characterized by molecular analysis using nucleotide sequences of partial LSU rRNA gene and the total ITS region. The homologous regions from relevant diaporthalean taxa available in the GenBank were also included and compared with the taxa sequenced in this study. Phylogenetic analyses revealed that G. fragariae, G. rubi, and Gnomonia sp. (CBS 850.79) were genetically different from G. gnomon, the type species of the genus, and other members of Gnomoniaceae. The analyses showed that G. fragariae and Hapalocystis were genetically very closely related, forming a phylogenetic clade, which is possibly presenting a new family in the Diaporthales. Morphological comparisons of the Gnomonia species on the basis of commonly used criteria for the taxonomy of Diaporthales, so far did not reveal any evident features for the polyphyletic status of Gnomonia.  相似文献   
50.
Variant Creutzfeldt-Jakob disease (vCJD) is an at present inevitably lethal neurodegenerative disease which can only be diagnosed definitely post mortem. The majority of the approximately 200 victims to date have resided in the UK where most contaminated beef materials entered the food chain. Three cases in the UK demonstrated that vCJD can be transmitted by blood transfusion. Since BSE and vCJD have spread to several countries outside the UK, it appears advisable that specific risk assessments be carried out in different countries and geographic areas. This review explains the approach adopted by Germany in assessing the risk and considering precautionary measures. A fundamental premise is that the feeding chain of cattle and the food chain have been successfully and permanently cleared from contaminated material. This raises the question of whether transmissions via blood transfusions could have the potential to perpetuate vCJD in mankind. A model calculation based on actual population data showed, however, that this would not be the case. Moreover, an exclusion of transfusion recipients from blood donation would add very little to the safety of blood transfusions, but would have a considerable impact on blood supply. Therefore, an exclusion of transfusion recipients was not recommended in Germany.  相似文献   
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