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81.
J. De La Cruz‐Agüero R. Moncayo‐Estrada V. M. Cota‐Gómez H. Villalobos‐Ortiz A. Valdez‐Pelayo 《Journal of fish biology》2016,89(3):1889-1896
The first records of three midwater species for the Mexican ichthyofauna (Holtbyrnia laticauda, Brama dussumieri and Cubiceps baxteri), caught off the coast of Baja California, Mexico, in mid 2014, are reported. As far as is known, they are the first verified specimens, geo‐referenced and catalogued in a reference fish collection for the west coast of Mexico. The species' known distributions were extended northward in the eastern Pacific Ocean, ranging from 3495 to 8300 km. 相似文献
82.
Spatio-temporal variability of the winter phytoplankton distribution across the Catalan and North Balearic fronts (NW Mediterranean) 总被引:1,自引:0,他引:1
The qualitative and quantitative composition of the phytoplankton
assemblages of the Catalano-Balearic Sea (NW Mediterranean) was examined in
relationship with frontal boundaries and short-term meteorological forcing
originated by an intense wind storm. Data were obtained during February
1990, before and after strong NW winds, from several transects across the
Catalan (continental side) and North Balearic (Balearic Islands side)
shelf/slope fronts. High chlorophyll concentrations and diatom dominance
inshore of the Catalan Front were typical of the winter-spring
phytoplankton maximum. However, offshore of the Catalan Front, diatoms were
scarce and the phytoplankton assemblage was dominated by coccolithophorids.
In spite of weak density stratification, a deep chlorophyll maximum (DCM)
was well developed, before the storm, offshore and appeared to cause a
pulse of new production, as suggested by increased oxygen concentrations in
the vicinity of the DCM. The results presented here indicate the existence
of a persistent association between the distribution of distinct
phytoplankton assemblages and hydrographic characteristics of the studied
area. Our results also show that, at least during an important part of the
winter-spring bloom period of the Catalano-Balearic Sea, high phytoplankton
biomass offshore of the Catalan Front is not associated with the diatom
dominance typically found in coastal waters and other offshore areas of the
NW Mediterranean. This finding has biogeochemical implications in
relationship with vertical export fluxes of particulate matter.
相似文献
83.
Safety Evaluation of Transgenic Tilapia with Accelerated Growth 总被引:2,自引:0,他引:2
Isabel Guillén Jorge Berlanga Carmen M. Valenzuela Antonio Morales José Toledo Mario P. Estrada Pedro Puentes Orlando Hayes José de la Fuente 《Marine biotechnology (New York, N.Y.)》1999,1(1):2-14
Recent advances in modern marine biotechnology have permitted the generation of new strains of economically important fish
species through the transfer of growth hormone genes. These transgenic fish strains show improved growth performance and therefore
constitute a better alternative for aquaculture programs. Recently, we have obtained a transgenic tilapia line with accelerated
growth. However, before introducing this line into Cuban aquaculture, environmental and food safety assessment was required
by national authorities. Experiments were performed to evaluate the behavior of transgenic tilapia in comparison to wild tilapia
as a way to assess the environmental impact of introducing transgenic tilapia into Cuban aquaculture. Studies were also conducted
to evaluate, according to the principle of substantial equivalence, the safety of consuming transgenic tilapia as food. Behavior
studies showed that transgenic tilapia had a lower feeding motivation and dominance status than controls. Food safety assessment
indicated that tilapia growth hormone has no biological activity when administered to nonhuman primates. Furthermore, no effects
were detected in human healthy volunteers after the consumption of transgenic tilapia. These results showed, at least under
the conditions found in Cuba, no environmental implications for the introduction of this transgenic tilapia line and the safety
in the consumption of tiGH-transgenic tilapia as an alternative feeding source for humans. These results support the culture
and consumption of these transgenic tilapia.
Received: March 9, 1998; accepted June 25, 1998. 相似文献
84.
In Neotropical rain forests, fresh mammal dung, especially that of howler monkeys, constitutes an important resource used by dung beetles as food and for oviposition and further feeding by their larvae. Tropical rain forest destruction, fragmentation, and subsequent isolation causing reductions in numbers of and the disappearance of howler moneys may result in decreasing numbers of dung beetles, but this has not been documented. In this study, we present information on the presence of howlers and dung beetles in 38 isolated forest fragments and 15 agricultural habitats. Howler monkeys were censused by visual means, while dung beetles were sampled with traps baited with a mixture of howler, cow, horse, and dog dung. Results indicated that loss of area and isolation of forest fragments result in significant decrements in howlers and dung beetles. However, dung beetle abundance was found to be closely related to the presence of howler monkeys at the sites and habitats investigated. Scenarios of land management designed to reduce isolation among forest fragments may help sustain populations of howler monkeys and dung beetles, which may have positive consequences for rain forest regeneration. Am. J. Primatol. 48:253–262, 1999. © 1999 Wiley‐Liss, Inc. 相似文献
85.
Matthew H. Van Dam Analyn Anzano Cabras James B. Henderson Andrew J. Rominger Cynthia Prez Estrada Arina D. Omer Olga Dudchenko Erez Lieberman Aiden Athena W. Lam 《PLoS genetics》2021,17(8)
Patterns of genomic architecture across insects remain largely undocumented or decoupled from a broader phylogenetic context. For instance, it is unknown whether translocation rates differ between insect orders. We address broad scale patterns of genome architecture across Insecta by examining synteny in a phylogenetic framework from open-source insect genomes. To accomplish this, we add a chromosome level genome to a crucial lineage, Coleoptera. Our assembly of the Pachyrhynchus sulphureomaculatus genome is the first chromosome scale genome for the hyperdiverse Phytophaga lineage and currently the largest insect genome assembled to this scale. The genome is significantly larger than those of other weevils, and this increase in size is caused by repetitive elements. Our results also indicate that, among beetles, there are instances of long-lasting (>200 Ma) localization of genes to a particular chromosome with few translocation events. While some chromosomes have a paucity of translocations, intra-chromosomal synteny was almost absent, with gene order thoroughly shuffled along a chromosome. This large amount of reshuffling within chromosomes with few inter-chromosomal events contrasts with patterns seen in mammals in which the chromosomes tend to exchange larger blocks of material more readily. To place our findings in an evolutionary context, we compared syntenic patterns across Insecta in a phylogenetic framework. For the first time, we find that synteny decays at an exponential rate relative to phylogenetic distance. Additionally, there are significant differences in decay rates between insect orders, this pattern was not driven by Lepidoptera alone which has a substantially different rate. 相似文献
86.
Bañares-Hidalgo A Bolaños-Gutiérrez A Gil F Cabré EJ Pérez-Gil J Estrada P 《Journal of industrial microbiology & biotechnology》2008,35(11):1367-1376
A recombinant form of the peptide N-terminally positioned from proSP-B (SP-BN) has been produced in Escherichia coli as fusion with the Maltose Binding Protein, separated from it by Factor Xa cleavage and purified thereafter. This protein
module is thought to control assembly of mature SP-B, a protein essential for respiration, in pulmonary surfactant as it progress
through the progressively acidified secretory pathway of pneumocytes. Self-aggregation studies of the recombinant propeptide
have been carried out as the pH of the medium evolved from neutral to moderately acid, again to neutral and finally basic.
The profile of aggregation versus subsequent changes in pH showed differences depending on the ionic strength of the medium, low or moderate, and the presence
of additives such as L-arginine (a known aggregation suppressor) and Ficoll 70 (a macromolecular crowder). Circular dichroism studies of SP-BN samples along the aggregation process showed a decrease in α-helical content and a concomitant increase in β-sheet. Intrinsic
fluorescence emission of SP-BN was dominated by the emission of Trp residues in neutral medium, being its emission maximum shifted to red at low pH, suggesting
that the protein undergoes a pH-dependent conformational change that increases the exposure of their Trp to the environment.
A marked increase in the fluorescence emission of the extrinsic probe bis-ANS indicated the exposure of hydrophobic regions
of SP-BN at pH 5. The fluorescence of bis-ANS decreased slightly at low ionic strength, but to a great extent at moderate ionic strength
when the pH was reversed to neutrality, suggesting that self-aggregation properties of the SP-BN module could be tightly modulated by the conditions of pH and the ionic environment encountered by pulmonary surfactant during
assembly and secretion. 相似文献
87.
Lendvai G Velikyan I Estrada S Eriksson B Långström B Bergström M 《Oligonucleotides》2008,18(1):33-49
In vivo monitoring of gene expression may be accomplished using a most advanced imaging technology such as positron emission tomography (PET). However, a range of methodological and biological hurdles needs exploration. In the present study, 20-mer DNA-LNA (locked nucleic acid) mixmer oligonucleotides specific for rat Chromogranin-A (Chg-A) mRNA were labeled with 68Ga and their biodistribution were investigated in rats; namely, two Antisense (LNA1, LNA2--differing only in the positioning of LNA modification), Mismatched, and Sense sequences. In addition, in vivo and in vitro metabolite analysis of LNA1 and LNA2 was compared, and hybridization in solution was performed to verify the hybridization ability after labeling. Furthermore, semiquantitative polymerase chain reaction was carried out to find organs expressing Chg-A mRNA in the rat. The biodistribution patterns altered according to the sequence and the positioning of LNA modification. The pattern of Mismatched--differing only in two nucleotides from the two Antisenses--was similar to that of Sense, whereas the pattern of LNA1 and LNA2 showed differences. Uptake in the adrenal gland was twofold higher with LNA2 compared to the other three oligonucleotides. Intact LNA2 could be observed in the 60-minute sample in vivo, whereas in vitro, the intact compound of both Antisenses could also be detected after 2 hours. Hybridization in solution revealed that the two Antisenses retained their hybridization abilities after 68Ga-labeling. With decreasing magnitude, Chg-A mRNA was expressed in the adrenal gland, intestine, testis, and pancreas. This study further supported LNA-DNA mixmer to be a favorable modification for antisense targeting approach with respect to hybridization and longer plasma residence; however, the organ uptake was dominated by processes irrelevant to specific hybridization. 相似文献
88.
Enrique Samper Lucia Morgado Juan C. Estrada Antonio Bernad Alan Hubbard Susana Cadenas Simon Melov 《Free radical biology & medicine》2009,46(3):387-396
Lymphomas adapt to their environment by undergoing a complex series of biochemical changes that are currently not well understood. To better define these changes, we examined the gene expression and gene ontology profiles of thymic lymphomas from a commonly used model of carcinogenesis, the p53?/? mouse. These tumors show a highly significant upregulation of mitochondrial biogenesis, mitochondrial protein translation, mtDNA copy number, reactive oxygen species, antioxidant defenses, proton transport, ATP synthesis, hypoxia response, and glycolysis, indicating a fundamental change in the bioenergetic profile of the transformed T cell. Our results suggest that T cell tumorigenesis involves a simultaneous upregulation of mitochondrial biogenesis, mitochondrial respiration, and glycolytic activity. These processes would allow cells to adapt to the stressful tumor environment by facilitating energy production and thereby promote tumor growth. Understanding these adaptations is likely to result in improved therapeutic strategies for this tumor type. 相似文献
89.
Alma E. Rodriguez Estrada Maria del Mar Jimenez-Gasco Daniel J. Royse 《Bioresource technology》2009,100(21):5270-5276
Improved yield and biological efficiency (BE) of Pleurotus eryngii var. eryngii were achieved by supplementation of substrate with a commercial delayed-release nutrient and use of a casing overlay. Yield increases of 14% were achieved from cased substrates that were supplemented at time of casing with delayed-release nutrient (Remo’s). Use of a casing layer enhanced yield by 141% over non-cased substrates. When casing and substrate supplementation were combined, yield increased 179% over non-cased/non-supplemented substrates. Mushrooms harvested from cased substrates were darker in color and solids contents were lower compared to non-cased substrates. An additional break of mushrooms was harvested from non-cased “spent” substrate by fragmenting and re-supplementing the substrate prior to the application of a casing overlay. Three production methods were compared for their effect on mushroom yield: “standard”, “casing” and “casing after first break”. Casing of the substrate before first break (“casing” production method) resulted in the highest yield and biological efficiency. 相似文献
90.
Rosendo Estrada Na Li Harshini Sarojini Jin AN Menq‐Jer Lee Eugenia Wang 《Journal of cellular physiology》2009,219(3):563-571
It is well known that bone marrow‐derived mesenchymal stem cells (MSCs) are involved in wound healing and regeneration responses. In this study, we globally profiled the proteome of MSCs to investigate critical factor(s) that may promote wound healing. Cysteine‐rich protein 61 (Cyr61) was found to be abundantly present in MSCs. The presence of Cyr61 was confirmed by immunofluorescence staining and immunoblot analysis. Moreover, we showed that Cyr61 is present in the culture medium (secretome) of MSCs. The secretome of MSCs stimulates angiogenic response in vitro, and neovascularization in vivo. Depletion of Cyr61 completely abrogates the angiogenic‐inducing capability of the MSC secretome. Importantly, addition of recombinant Cyr61 polypeptides restores the angiogenic activity of Cyr61‐depleted secretome. Collectively, these data demonstrate that Cyr61 polypeptide in MSC secretome contributes to the angiogenesis‐promoting activity, a key event needed for regeneration and repair of injured tissues. J. Cell. Physiol. 219: 563–571, 2009. © 2009 Wiley‐Liss, Inc. 相似文献