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61.
Ankit Verma Dhirendra Kumar Sharma Rituparna Sarma Hasnahana Chetia Juri Saikia 《Bioinformation》2013,9(15):755-758
BDNF (Brain derived neurotrophic factor) is a secretion protein and a member of the neurotrophin family of growth factors.
Structural and functional characterization of BDNF Varanus komodoensis is of interest while its structure remains unknown. Thus, a
homology molecular model of BDNF was constructed for gleaning possible structural insights. The model was compared with the
structure of the homologous NGF (Nerve growth factor, another member of neuro-trophin family) from Naja atra. Comparative
structural analysis of the models showed structural similarities with their predicted cavities for the interpretation of potential
functional analogy. 相似文献
62.
Irena Trbojević-Akmačić Frano Vučković Marija Vilaj Andrea Skelin Lennart C. Karssen Jasminka Krištić Julija Jurić Ana Momčilović Jelena Šimunović Massimo Mangino Manuela De Gregori Maurizio Marchesini Concetta Dagostino Jerko Štambuk Mislav Novokmet Richard Rauck Yurii S. Aulchenko Dragan Primorac Gordan Lauc 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(10):2124-2133
Background
Low back pain (LBP) is the symptom of a group of syndromes with heterogeneous underlying mechanisms and molecular pathologies, making treatment selection and patient prognosis very challenging. Moreover, symptoms and prognosis of LBP are influenced by age, gender, occupation, habits, and psychological factors. LBP may be characterized by an underlying inflammatory process. Previous studies indicated a connection between inflammatory response and total plasma N-glycosylation. We wanted to identify potential changes in total plasma N-glycosylation pattern connected with chronic low back pain (CLBP), which could give an insight into the pathogenic mechanisms of the disease.Methods
Plasma samples of 1128 CLBP patients and 760 healthy controls were collected in clinical centers in Italy, Belgium and Croatia and used for N-glycosylation profiling by hydrophilic interaction ultra-performance liquid chromatography (HILIC-UPLC) after N-glycans release, fluorescent labeling and clean-up. Observed N-glycosylation profiles have been compared with a cohort of 126 patients with acute inflammation that underwent abdominal surgery.Results
We have found a statistically significant increase in the relative amount of high-branched (tri-antennary and tetra-antennary) N-glycan structures on CLBP patients' plasma glycoproteins compared to healthy controls. Furthermore, relative amounts of disialylated and trisialylated glycan structures were increased, while high-mannose and glycans containing bisecting N-acetylglucosamine decreased in CLBP.Conclusions
Observed changes in CLBP on the plasma N-glycome level are consistent with N-glycosylation changes usually seen in chronic inflammation.General significance
To our knowledge, this is a first large clinical study on CLBP patients and plasma N-glycome providing a new glycomics perspective on potential disease pathology. 相似文献63.
64.
65.
Renata Jurišić Grubešić Sanda Vladimir-Knežević Dario Kremer Zdenka Kalodera Jadranka Vuković 《Biologia》2007,62(2):148-156
Micromorphological investigation of the types, dimensions and distribution of characteristic trichomes in leaves and stems
in Teucrium L. species (T. arduini L., T. chamaedrys L., T. flavum L., T. montanum L., T. polium L., and T. scordium L. subsp. scordioides Schreb.) distributed in Croatia was carried out as part of the taxonomical study of the genus Teucrium. Secretory types of hairs, peltate and capitate hairs were observed on the epidermis of stems and leaves of all investigated
species. Non-secretory, acicular hairs were almost completely lacking on stems of T. scordium subsp. scordioides. Flagelliform hairs were not found in T. flavum and T. polium. Cladose hairs were present only in T. polium. The largest micromorphological variability was established between wild and cultivated samples of T. arduini and T. scordium subsp. scordioides, while cultivated and wild specimens of T. polium were almost identical. Differences were primarily observed in trichome dimensions and much less in micromorphological features. 相似文献
66.
Marco Cervellini Michele Di Musciano Piero Zannini Simone Fattorini Borja JimnezAlfaro Emiliano Agrillo Fabio Attorre Pierangela Angelini Carl Beierkuhnlein Laura Casella Richard Field JanChristopher Fischer Piero Genovesi Samuel Hoffmann Severin D. H. Irl Juri Nascimbene Duccio Rocchini Manuel Steinbauer Ole R. Vetaas Alessandro Chiarucci 《Ecology and evolution》2021,11(24):18111
Habitat richness, that is, the diversity of ecosystem types, is a complex, spatially explicit aspect of biodiversity, which is affected by bioclimatic, geographic, and anthropogenic variables. The distribution of habitat types is a key component for understanding broad‐scale biodiversity and for developing conservation strategies. We used data on the distribution of European Union (EU) habitats to answer the following questions: (i) how do bioclimatic, geographic, and anthropogenic variables affect habitat richness? (ii) Which of those factors is the most important? (iii) How do interactions among these variables influence habitat richness and which combinations produce the strongest interactions? The distribution maps of 222 terrestrial habitat types as defined by the Natura 2000 network were used to calculate habitat richness for the 10 km × 10 km EU grid map. We then investigated how environmental variables affect habitat richness, using generalized linear models, generalized additive models, and boosted regression trees. The main factors associated with habitat richness were geographic variables, with negative relationships observed for both latitude and longitude, and a positive relationship for terrain ruggedness. Bioclimatic variables played a secondary role, with habitat richness increasing slightly with annual mean temperature and overall annual precipitation. We also found an interaction between anthropogenic variables, with the combination of increased landscape fragmentation and increased population density strongly decreasing habitat richness. This is the first attempt to disentangle spatial patterns of habitat richness at the continental scale, as a key tool for protecting biodiversity. The number of European habitats is related to geography more than climate and human pressure, reflecting a major component of biogeographical patterns similar to the drivers observed at the species level. The interaction between anthropogenic variables highlights the need for coordinated, continental‐scale management plans for biodiversity conservation. 相似文献
67.
Itaru Ohta Yuichi Akita Masato Uehara Akihiko Ebisawa 《Environmental Biology of Fishes》2017,100(11):1451-1467
The demography and reproductive biology of three Epinephelus groupers (Serranidae), namely E. polyphekadion, E. tauvina, and E. howlandi in the Yaeyama Islands, Okinawa, were examined based on age assessment using otoliths and gonadal histology. The maximum ages for these three species were 26 year, 23 year, and 17 year. The von Bertalanffy growth functions were also determined for each species. The size and age at 50% female maturity were estimated to be 358 mm in total length (TL) and 6.0 year for E. polyphekadion, 371 mm TL and 6.7 year for E. tauvina, and 327 mm TL and 4.1 year for E. howlandi, respectively. Significant differences between the sexes in size and age frequencies were found in all three species, with males being larger and older than females, or transitional individuals. These results strongly indicated that the population of these three grouper species showed monandric protogynous hermaphroditism. The sex ratios of E. polyphekadion and E. tauvina were biased in favor of females, but that of E. howlandi was equivalent between sexes. The relative sizes of ripe testes indicated that the intensity of sperm competition varied among species suggesting different mating system of each species. Reproductive seasonality was similar among species, with active vitellogenesis coinciding with the annual rise in water temperature. The active spawning period was determined to be between April and May for E polyphekadion, in May for E. howlandi, and from March to June for E. tauvina. 相似文献
68.
69.
Hiroko Shimada Kahori Numazawa Tsukasa Sasaki Nobumasa Kato Takashi Ebisawa 《Cellular and molecular neurobiology》2009,29(5):699-705
We aim to develop a cultured cell model, to serve as a system with which the altered circadian phenotypes produced by the
clock gene variations could be studied in vitro. Tau mutation, which shortens the circadian period of hamsters and mice, was introduced into the CK1ε locus of cultured Rat1-R12 cells by gene targeting mediated by a recombinant adeno-associated virus (rAAV) vector. After
transduction of Rat1-R12 cells with rAAV, about 0.14% of the drug-resistant cells underwent gene targeting at CK1ε locus. Of the three clones isolated, only one carried the targeted allele of tau mutation and two carried the targeted wild-type allele. The clone with the targeted tau mutant allele exhibited a significantly shorter circadian period compared to the clone with targeted wild-type allele. rAAV-mediated
gene targeting in cultured somatic cells is a convenient and powerful tool for analyzing the phenotypic outcome of clock gene
variations, and for elucidating the pathogenesis of the disorders associated with abnormal circadian rhythmicity. 相似文献
70.
The 1-deoxy-d-xylulose 5-phosphate synthase gene co-localizes with a major QTL affecting monoterpene content in grapevine 总被引:2,自引:0,他引:2
Juri Battilana Laura Costantini Francesco Emanuelli Federica Sevini Cinzia Segala Sergio Moser Riccardo Velasco Giuseppe Versini M. Stella Grando 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,118(4):653-669
Muscat flavor is a relevant trait both in winemaking and in fresh grape consumption. From a chemical point of view, it is
strongly related to the accumulation of monoterpenes in berries. However, knowledge of the genetic mechanisms underlying its
regulation is still limited. The objective of this study was to dissect the genetic determinism of aroma in grapevine by applying
the analysis of quantitative trait loci (QTL) and the candidate gene (CG) approach. Two F1 segregating progenies were evaluated through high-resolution gas chromatography–mass spectrometry (HRGC–MS) for the amounts
of individual monoterpenes over 3 and 2 years. In the Italia × Big Perlon cross 34 CGs, chosen according to gene ontology
(GO) terms, were placed on a complete map and tested for linkage with QTLs for linalool, nerol and geraniol levels. Two CGs
mapped within a QTL for linalool content on LG 10. A third one co-localized with a major QTL for the level of the three monoterpenes
on LG 5; this gene encodes 1-deoxy-d-xylulose 5-phosphate synthase (DXS), which is the first enzyme in the plastidial pathway of terpene biosynthesis. Depending
on these findings, we report the first in silico analysis of grapevine DXS genes based on the whole genome sequence. Further research on the functional significance of these associations might help
to understand the genetic control of Muscat flavor.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
J. Battilana and L. Costantini equally contributed to the work. 相似文献