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341.
342.
Tiziana della Ragione Greta Verheyen Evangelos G Papanikolaou Lisbet Van Landuyt Paul Devroey Andre Van Steirteghem 《Reproductive biology and endocrinology : RB&E》2007,5(1):2-8
Background
In IVF-ICSI cycles with single embryo transfer (SET), embryo selection for transfer is of crucial importance. The present study aimed to define which embryo parameters might be related to the implantation potential of advanced blastocysts. 相似文献343.
Evangelos Koustas Michalis V. Karamouzis Panagiotis Sarantis Dimitrios Schizas Athanasios G. Papavassiliou 《Journal of cellular and molecular medicine》2020,24(18):10420-10431
Gastric cancer is the fifth most common malignancy and the third leading cause of cancer‐related death worldwide. Activation of c‐MET increases tumour cell survival through the initiation of the DNA damage repair pathway. PARP is an essential key in the DNA damage repair pathway. The primary role of PARP is to detect and initiate an immediate cellular response to single‐strand DNA breaks. Tumours suppressor genes such as BRCA1/2 are closely associated with the DNA repair pathway. In BRCA1/2 mutations or deficiency status, cells are more likely to develop additional genetic alterations and chromosomal instability and can lead to cancer. In this study, we investigate the role of c‐MET and PARP inhibition in a gastric cancer model. We exploited functional in vitro and in vivo experiments to assess the antitumour potential of co‐inhibition of c‐MET (SU11274) and PARP (NU1025). This leads to a reduction of gastric cancer cells viability, especially after knockdown of BRCA1/2 through apoptosis and induction of γ‐Η2ΑΧ. Moreover, in AGS xenograft models, the combinatorial treatment of NU1025 plus SU11274 reduced tumour growth and triggers apoptosis. Collectively, our data may represent a new therapeutic approach for GC thought co‐inhibition of c‐MET and PARP, especially for patients with BRCA1/2 deficiency tumours. 相似文献
344.
Evangelos Spyrakos Tania C. Santos-Diniz Gema Martinez-Iglesias Jesus M. Torres-Palenzuela Graham J. Pierce 《Hydrobiologia》2011,670(1):87-109
The spatial and seasonal distribution of cetaceans and possible links with environmental conditions were studied at the Galician
continental shelf. Data were collected between February–August 2001 and June–September 2003 during opportunistic surveys onboard
fishing boats. Seven species of cetaceans were identified from 250 sightings of 6,846 individuals. The common dolphin (Delphinus delphis) was by far the most frequently sighted and the most widely distributed species. Spatiotemporal trends in cetacean distribution
and abundance, and their relationships with environmental parameters (sea depth, SST and chlorophyll-a) were quantified using generalised additive models (GAMs). Results for all cetaceans were essentially the same as for common
dolphins alone. Modelling results indicated that the number of common dolphin sightings per unit effort was higher further
south. The number of individual common dolphins seen per sighting of this species (i.e. group size) was however higher in
the north and west of the study area, higher later in the year and higher in 2001 than in 2003. In contrast, the number of
common dolphin calves seen (per sighting of this species) was higher in the south. Models including environmental variables
indicated larger common dolphin group sizes in deeper waters and at higher chlorophyll concentrations (i.e. in more productive
areas). There was also a positive relationship between survey effort and group size, which is probably an artefact of the
tendency of the survey platforms (fishing boats) to spend most time in areas of high fish abundance. Numbers of common dolphin
calves per sighting were found to be higher in shallower waters. The results are consistent with common dolphins foraging
mainly in deeper waters of the Galician continental shelf, while more southern inshore waters may represent a nursery area. 相似文献
345.
Light interception and radiation use efficiency of okra and normal leaf cotton isolines 总被引:1,自引:0,他引:1
Evangelos D. Gonias Derrick M. OosterhuisAndroniki C. Bibi 《Environmental and Experimental Botany》2011,72(2):217-222
Okra-leaf cotton (Gossypium hirsutum L.) types have been reputed to produce equal or higher amounts of lint yield than normal-leaf types, while intercepting less or similar amounts of radiation. In this field study, okra- and normal-leaf cotton isolines were compared for their efficiency to produce dry matter utilizing intercepted radiation. At three weeks after first flower, the two leaf-shape isolines produced similar amounts of dry matter, with the okra-leaf type partitioning a larger fraction to fruiting organs. However, at the end of the season no differences in lint yield, yield components and fiber-quality properties were recorded between the two isolines. Fractional light interception throughout the period of the study was greater for the normal-leaf type compared to the okra-leaf type. The okra-leaf isoline utilized intercepted radiation more efficiently to produce dry matter. Values of radiation use efficiency were estimated at 1.897 and 2.636 g MJ−1 of intercepted photosynthetically active radiation for the normal- and okra-leaf types, respectively. Growth chamber studies revealed similar single leaf carbon exchange rates, therefore radiation use efficiency differences between the leaf shape isolines could be attributed to light interception characteristics. 相似文献
346.
Leroy S Bouissou F Fernandez-Lopez A Gurgoze MK Karavanaki K Ulinski T Bressan S Vaos G Leblond P Coulais Y Cubells CL Aygun AD Stefanidis CJ Bensman A Da Dalt L DaDalt L Gardikis S Bigot S Gendrel D Bréart G Chalumeau M 《PloS one》2011,6(12):e29556
Background
Predicting vesico-ureteral reflux (VUR) ≥3 at the time of the first urinary tract infection (UTI) would make it possible to restrict cystography to high-risk children. We previously derived the following clinical decision rule for that purpose: cystography should be performed in cases with ureteral dilation and a serum procalcitonin level ≥0.17 ng/mL, or without ureteral dilatation when the serum procalcitonin level ≥0.63 ng/mL. The rule yielded a 86% sensitivity with a 46% specificity. We aimed to test its reproducibility.Study Design
A secondary analysis of prospective series of children with a first UTI. The rule was applied, and predictive ability was calculated.Results
The study included 413 patients (157 boys, VUR ≥3 in 11%) from eight centers in five countries. The rule offered a 46% specificity (95% CI, 41–52), not different from the one in the derivation study. However, the sensitivity significantly decreased to 64% (95%CI, 50–76), leading to a difference of 20% (95%CI, 17–36). In all, 16 (34%) patients among the 47 with VUR ≥3 were misdiagnosed by the rule. This lack of reproducibility might result primarily from a difference between derivation and validation populations regarding inflammatory parameters (CRP, PCT); the validation set samples may have been collected earlier than for the derivation one.Conclusions
The rule built to predict VUR ≥3 had a stable specificity (ie. 46%), but a decreased sensitivity (ie. 64%) because of the time variability of PCT measurement. Some refinement may be warranted. 相似文献347.
Oliver Robinson Marc Chadeau Hyam Ibrahim Karaman Rui Climaco Pinto Mika Ala-Korpela Evangelos Handakas Giovanni Fiorito He Gao Andy Heard Marjo‐Riitta Jarvelin Matthew Lewis Raha Pazoki Silvia Polidoro Ioanna Tzoulaki Matthias Wielscher Paul Elliott Paolo Vineis 《Aging cell》2020,19(6)
Markers of biological aging have potential utility in primary care and public health. We developed a model of age based on untargeted metabolic profiling across multiple platforms, including nuclear magnetic resonance spectroscopy and liquid chromatography–mass spectrometry in urine and serum, within a large sample (N = 2,239) from the UK Airwave cohort. We validated a subset of model predictors in a Finnish cohort including repeat measurements from 2,144 individuals. We investigated the determinants of accelerated aging, including lifestyle and psychological risk factors for premature mortality. The metabolomic age model was well correlated with chronological age (mean r = .86 across independent test sets). Increased metabolomic age acceleration (mAA) was associated after false discovery rate (FDR) correction with overweight/obesity, diabetes, heavy alcohol use and depression. DNA methylation age acceleration measures were uncorrelated with mAA. Increased DNA methylation phenotypic age acceleration (N = 1,110) was associated after FDR correction with heavy alcohol use, hypertension and low income. In conclusion, metabolomics is a promising approach for the assessment of biological age and appears complementary to established epigenetic clocks. 相似文献
348.
Biological traits can determine species ecological niches and define species responses to environmental variation. Species have a specific functional position in the biological community, resulting in interactions like interspecific competition. In this study, we used biological traits in order to define the life strategies of 205 nektonic species of the Mediterranean Sea. Furthermore, traits related to resource use were analyzed to determine the level of trait and niche overlap and their relationship to life strategies. Focusing on habitats of importance (Posidonia beds, coralligène formations, and lagoons), we investigated strategies and niches of the species present there. Finally, we examined the life strategy of Lessepsian species and investigated the niche overlap between them and indigenous species. Archetypal analysis indicated the existence of three life histories corresponding to strategies already documented for fish (equilibrium, periodic, and opportunistic), with some species also placed in intermediate positions. Niche overlap was evaluated by multiple correspondence analysis and the generation of a single distance metric between all species pairs. This identified species occupying relatively empty (underexploited) ecological niches, like the Lessepsian species Siganus luridus and S. rivulatus, a finding that can also be associated with their establishment in the Mediterranean. Most Lessepsian species were associated with the opportunistic life history strategy, again an important aspect related to their establishment. Also, we documented that most species occurring in important habitats have a relatively high overlap of niches. No significant differences were found in the life strategies across Mediterranean habitats; however, variation in niche overlap and traits related to habitat use was detected. The findings can be useful to determine theoretical competition between species and to identify empty ecological niches. Fisheries science can also benefit from comprehending the dynamics of competing stocks or predict the responses of data‐poor stocks to anthropogenic stressors from known examples of species with shared life strategies. 相似文献
349.
Evangelos Pafilis Sune P. Frankild Lucia Fanini Sarah Faulwetter Christina Pavloudi Aikaterini Vasileiadou Christos Arvanitidis Lars Juhl Jensen 《PloS one》2013,8(6)
The exponential growth of the biomedical literature is making the need for efficient, accurate text-mining tools increasingly clear. The identification of named biological entities in text is a central and difficult task. We have developed an efficient algorithm and implementation of a dictionary-based approach to named entity recognition, which we here use to identify names of species and other taxa in text. The tool, SPECIES, is more than an order of magnitude faster and as accurate as existing tools. The precision and recall was assessed both on an existing gold-standard corpus and on a new corpus of 800 abstracts, which were manually annotated after the development of the tool. The corpus comprises abstracts from journals selected to represent many taxonomic groups, which gives insights into which types of organism names are hard to detect and which are easy. Finally, we have tagged organism names in the entire Medline database and developed a web resource, ORGANISMS, that makes the results accessible to the broad community of biologists. The SPECIES software is open source and can be downloaded from http://species.jensenlab.org along with dictionary files and the manually annotated gold-standard corpus. The ORGANISMS web resource can be found at http://organisms.jensenlab.org. 相似文献
350.
Pinelopi?Dragoumi Olga?Tzetzi Efthimia?Vargiami Evangelos?Pavlou Konstantinos?Krikonis Eleftherios?Kontopoulos Dimitrios?I?ZafeiriouEmail author 《BMC neurology》2013,13(1):206