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941.
Angela Meccariello Konstantina T. Tsoumani Andrea Gravina Pasquale Primo Martina Buonanno Kostas D. Mathiopoulos Giuseppe Saccone 《Archives of insect biochemistry and physiology》2020,104(2):e21667
The olive fruit fly, Bactrocera oleae (Diptera: Tephritidae), is the most destructive insect pest of olive cultivation, causing significant economic and production losses. Here, we present the establishment of the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 methodology for gene disruption in this species. We performed targeted mutagenesis of the autosomal gene white (Bo-we), by injecting into early embryos in vitro preassembled and solubilized Cas9 ribonucleoprotein complexes loaded with two gene-specific single-guide RNAs. Gene disruption of Bo-we led to somatic mosaicism of the adult eye color. Large eye patches or even an entire eye lost the iridescent reddish color, indicating the successful biallelic mutagenesis in somatic cells. Cas9 induced either indels in each of the two simultaneously targeted Bo-we sites or a large deletion of the intervening region. This study demonstrates the first efficient implementation of the CRISPR/Cas9 technology in the olive fly, providing new opportunities towards the development of novel genetic tools for its control. 相似文献
942.
Stefano Mazzoleni Fabrizio Cartenì Giuliano Bonanomi Guido Incerti Maria Luisa Chiusano Pasquale Termolino Antonello Migliozzi Mauro Senatore Francesco Giannino Max Rietkerk Antonio Risitano Virginia Lanzotti 《Phytochemistry Reviews》2014,13(4):937-946
The research for new products against pathogens, parasites and infesting species, in both agriculture and medicine, implies huge and increasing scientific, industrial and economic efforts. Traditional approaches are based on random screening procedures searching for bioactive compounds. However, the success of such methodologies in most cases has been strongly limited by side-effects of the potential new drugs, especially toxicity and pharmacological resistance. The use of nucleic acids in drug development has been introduced searching for target-specific effect. In addition, a recent discovery revealed that randomly fragmented extracellular self-DNA may act as highly species-specific inhibitory product for different species, suggesting an unprecedented use of DNA for biological control. On this base, a new scenario of pharmacological applications is discussed. 相似文献
943.
Ilaria De Pasquale Raffaella Di Cagno Solange Buchin Maria De Angelis Marco Gobbetti 《Applied and environmental microbiology》2014,80(19):6243-6255
Pyrosequencing of the 16S rRNA targeting RNA, community-level physiological profiles made with Biolog EcoPlates, proteolysis, and volatile component (VOC) analyses were mainly used to characterize the manufacture and ripening of the pasta filata cheese Caciocavallo Pugliese. Plate counts revealed that cheese manufacture affected the microbial ecology. The results agreed with those from culture-independent approaches. As shown by urea-PAGE, reverse-phase high pressure liquid chromatography (RP-HPLC), and free-amino-acid (FAA) analyses, the extent of secondary proteolysis mainly increased after 30 to 45 days of ripening. VOCs and volatile free fatty acids (VFFA) were identified by a purge-and-trap method (PT) and solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS), respectively. Except for aldehydes, the levels of most of VOCs and VFFA mainly increased from 30 to 45 days onwards. As shown through pyrosequencing analysis, raw cows'' milk was contaminated by Firmicutes (53%), Proteobacteria (39%), Bacteroidetes (7.8%), Actinobacteria (0.06%), and Fusobacteria (0.03%), with heterogeneity at the genus level. The primary starter Streptococcus thermophilus dominated the curd population. Other genera occurred at low incidence or sporadically. The microbial dynamics reflected on the overall physiological diversity. At 30 days, a microbial succession was clearly highlighted. The relative abundance of Streptococcus sp. and especially St. thermophilus decreased, while that of Lactobacillus casei, Lactobacillus sp., and especially Lactobacillus paracasei increased consistently. Despite the lower relative abundance compared to St. thermophilus, mesophilic lactobacilli were the only organisms positively correlated with the concentration of FAAs, area of hydrophilic peptide peaks, and several VOCs (e.g., alcohols, ketones, esters and all furans). This study showed that a core microbiota was naturally selected during middle ripening, which seemed to be the main factor responsible for cheese ripening. 相似文献
944.
Pasquale Chieco Ard Jonker Cinzia Melchiorri Gabriele Vanni Cornelis J. F. Van Noorden 《The Histochemical journal》1994,26(1):1-19
Summary The sources of errors which may occur when cytophotometric analysis is performed with video microscopy using a charged-coupled
device (CCD) camera and image analysis are reviewed. The importance of these errors in practice has been tested, and ways
of minimizing or avoiding them are described. Many of these sources of error are known from scanning and integrating cytophotometry;
they include the use of white instead of monochromatic light, the distribution error, glare, diffraction, shading distortion,
and inadequate depth of field. Sources of errors specifically linked with video microscopy or image analysis are highlighted
as well; these errors include blooming, limited dynamic range of grey levels, non-linear responses of the camera, contrast
transfer, photon noise, dark current, read-out noise, fixed scene noise and spatial calibration. Glare, contrast transfer,
fixed scene noise, depth of field and spatial calibration seem to be the most serious sources of errors when measurements
are not carried out correctly. We include a table summarizing all the errors discussed in this review and procedures for avoiding
them. It can be concluded that if accurate calibration steps are performed and proper guidelines followed, image cytometry
can be applied safely for quantifying amounts of chromophore per cell or per unit volume of tissue in sections, even when
relatively simple and inexpensive instrumentation is being used. 相似文献
945.
G. Paolo Littarru Silvio Lippa Pasquale De Sole Alessandro Oradei Francesco Dalla Torre Maria Macri 《Biochemical and biophysical research communications》1984,119(3):1056-1061
The ability of D-α-tocopherol to act as a quencher of 1O2 (singlet oxygen) was tested with a biological source of 1O2, namely the phagocytosis activated myeloperoxidase contained in the homogenate of human circulating polymorphonuclear leukocytes.With this system, the 1O2 quenching efficiency of exogenously added D-α-tocopherol was estimated from its inhibitory effect on the luminol amplified chemiluminescence. This inhibitory effect was dose dependent. D-α-tocopherol was also efficient in quenching the chemiluminescence generated through the H2O2-horseradish system. In both systems the quenching effect may be almost entirely “physical”, since very little tocopherol was destroyed when compared to the relatively large amount of H2O2 consumed. 相似文献
946.
947.
Giuseppina Nocca Alessandro Lupi Fabio De Santis Bruno Giardina Francesco De Palma Claudio Chimenti Gianluca Gambarini Pasquale De Sole 《Luminescence》2008,23(1):54-57
In the last years the studies regarding the biocompatibility of dental materials investigate, in addition to the classic cytotoxic tests, the interactions between the materials and the host cells to better explain the causes of the adverse effects observed sometimes in the clinical practice. In the present study the ability of diurethane dimethacrylate (DUDMA) and 1,4‐butanediol dimethacrylate (BDDMA) methacrylic monomers present in dental composite resins to alter the functionality of peripheral blood monocytes (PBMs) and polymorphonucleate cells (PMNs) was examined. These cells are involve in the biological response to materials and in the host ability to respond to bacteria. The results obtained suggest that the examined methacrylates induce a relevant decrease of PBMs oxidative burst whereas the basal ROS production is only slightly decreased. In PMNs DUDMA induces a decrease of both basal and stimulated ROS production. BDDMA, on the contrary, it does not alter total oxidative burst in presence of stimulus while induces a statistically significant decrease of basal ROS production. Moreover this monomer alters the reaction kinetics of stimulated ROS production. The reported finding seems to indicate that this molecule could be able to stabilize PMNs in resting state and maximize their stimulated activity. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
948.
Carla Reale Anna Iervolino Ivan Scudiero Angela Ferravante Luca Egildo D'Andrea Pellegrino Mazzone Tiziana Zotti Antonio Leonardi Luca Roberto Mariastella Zannini Tiziana de Cristofaro Muralitharan Shanmugakonar Giovambattista Capasso Manolis Pasparakis Pasquale Vito Romania Stilo 《The Journal of biological chemistry》2016,291(11):5765-5773
949.
Biodiversity and Conservation - This research examines a portion of the Italian alpine landscape in order to find a comprehension mode and a strategic proposal to safeguard this rural heritage. The... 相似文献
950.
Cells have been grown in vitro in the presence of radioactive precursors; much of the glucosamine label is incorporated into the surface material, part of it is then spontaneously released into the medium, part is readily removed by an EDTA wash, and further amounts may be released by a mild trypsin treatment or by a period of chase.The material in the EDTA was from variously labelled cultures has been fractionated by Sephadex G-200 chromatography; the excluded peak has been analysed by Sepharose 6B and DEAE-cellulose chromatography and by electrophoresis on large pore polyacrylamide gels. Its sensitivity to pronase and hyaluronidase has been determined, as well as its sugar, lipids and amino acid composition.Cell-coat material from Polyoma and Rous sarcoma virus-transformed cell lines failed to show significant differences in chromatographic properties and in sugar and amino acid composition. Minor but reproducible differences were found in the polyacrylamide electrophoresis migration patterns, when comparing glucosamine-labelled materials. 相似文献