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排序方式: 共有7316条查询结果,搜索用时 15 毫秒
61.
Marta Coll Chiara Piroddi Camille Albouy Frida Ben Rais Lasram William W. L. Cheung Villy Christensen Vasiliki S. Karpouzi François Guilhaumon David Mouillot Michelle Paleczny Maria Lourdes Palomares Jeroen Steenbeek Pablo Trujillo Reg Watson Daniel Pauly 《Global Ecology and Biogeography》2012,21(4):465-480
Aim A large body of knowledge exists on individual anthropogenic threats that have an impact on marine biodiversity in the Mediterranean Sea, although we know little about how these threats accumulate and interact to affect marine species and ecosystems. In this context, we aimed to identify the main areas where the interaction between marine biodiversity and threats is more pronounced and to assess their spatial overlap with current marine protected areas in the Mediterranean. Location Mediterranean Sea. Methods We first identified areas of high biodiversity of marine mammals, marine turtles, seabirds, fishes and commercial or well‐documented invertebrates. We mapped potential areas of high threat where multiple threats are occurring simultaneously. Finally we quantified the areas of conservation concern for biodiversity by looking at the spatial overlap between high biodiversity and high cumulative threats, and we assessed the overlap with protected areas. Results Our results show that areas with high marine biodiversity in the Mediterranean Sea are mainly located along the central and north shores, with lower values in the south‐eastern regions. Areas of potential high cumulative threats are widespread in both the western and eastern basins, with fewer areas located in the south‐eastern region. The interaction between areas of high biodiversity and threats for invertebrates, fishes and large animals in general (including large fishes, marine mammals, marine turtles and seabirds) is concentrated in the coastal areas of Spain, Gulf of Lions, north‐eastern Ligurian Sea, Adriatic Sea, Aegean Sea, south‐eastern Turkey and regions surrounding the Nile Delta and north‐west African coasts. Areas of concern are larger for marine mammal and seabird species. Main conclusions These areas may represent good candidates for further research, management and protection activities, since there is only a maximum 2% overlap between existing marine protected areas (which cover 5% of the Mediterranean Sea) and our predicted areas of conservation concern for biodiversity. 相似文献
62.
63.
Bruno Mendes Roatt Rodrigo Dian de Oliveira Aguiar-Soares Juliana Vitoriano-Souza Wendel Coura-Vital Samuel Le?ncio Braga Rodrigo Corrêa-Oliveira Olindo Assis Martins-Filho Andréa Teixeira-Carvalho Marta de Lana Nelder Figueiredo Gontijo Marcos José Marques Rodolfo Cordeiro Giunchetti Alexandre Barbosa Reis 《PloS one》2012,7(11)
In the last decade, the search for new vaccines against canine visceral leishmaniasis has intensified. However, the pattern related to immune protection during long periods after experimental infection in vaccine trials is still not fully understood. Herein, we investigated the immunogenicity and parasitological levels after intradermal challenge with Leishmania infantum plus salivary gland extract in dogs immunized with a vaccine composed of L. braziliensis antigens plus saponin as an adjuvant (LBSap vaccine). The LBSap vaccine elicited higher levels of total anti-Leishmania IgG as well as both IgG1 and IgG2. Furthermore, dogs vaccinated had increased levels of lymphocytes, particularly circulating B cells (CD21+) and both CD4+ and CD8+ T lymphocytes. LBSap also elicited an intense in vitro cell proliferation associated with higher levels of CD4+ T lymphocytes specific for vaccine soluble antigen and soluble lysate of L. infantum antigen even 885 days after experimental challenge. Furthermore, LBSap vaccinated dogs presented high IFN-γ and low IL-10 and TGF-β1 expression in spleen with significant reduction of parasite load in this tissue. Overall, our results validate the potential of LBSap vaccine to protect against L. infantum experimental infection and strongly support further evaluation of efficiency of LBSap against CVL in natural infection conditions. 相似文献
64.
Sara Benedetti Pia Bernasconi Enrico Bertini Elena Biagini Giuseppe Boriani Cristina Capanni Nicola Carboni Giovanna Cenacchi Marta Columbaro Monica D’Adamo Adele D’Amico Maria Rosaria D’Apice Marianna Fontana Alessandra Gambineri Giovanna Lattanzi Rocco Liguori Nadir M Maraldi Laura Mazzanti Eugenio Mercuri Tiziana Mongini Lucia O Morandi Iria Neri Giovanni Nigro Giuseppe Novelli Michela Ortolani Renato Pasquali Antonella Pini Stefania Petrini Luisa Politano Stefano Previtali Lisa Pucci Claudio Rapezzi Giulia Ricci Carmelo Rodolico Paolo Sbraccia Emanuela Scarano Gabriele Siciliano Stefano Squarzoni Antonio Toscano Liliana Vercelli Matteo Ziacchi 《Orphanet journal of rare diseases》2012,7(1):1-3
The need for a collaborative approach to complex inherited diseases collectively referred to as laminopathies, encouraged Italian researchers, geneticists, physicians and patients to join in the Italian Network for Laminopathies, in 2009. Here, we highlight the advantages and added value of such a multidisciplinary effort to understand pathogenesis, clinical aspects and try to find a cure for Emery-Dreifuss muscular dystrophy, Mandibuloacral dysplasia, Hutchinson-Gilford Progeria and forms of lamin-linked cardiomyopathy, neuropathy and lipodystrophy. 相似文献
65.
Hicham Benzekri Paula Armesto Xavier Cousin Mireia Rovira Diego Crespo Manuel Alejandro Merlo David Mazurais Rocío Bautista Darío Guerrero-Fernández Noe Fernandez-Pozo Marian Ponce Carlos Infante Jose Luis Zambonino Sabine Nidelet Marta Gut Laureana Rebordinos Josep V Planas Marie-Laure Bégout M Gonzalo Claros Manuel Manchado 《BMC genomics》2014,15(1)
66.
Xudong Liu Chuan-En Wang Yan Hong Ting Zhao Guohao Wang Marta A. Gaertig Miao Sun Shihua Li Xiao-Jiang Li 《PLoS genetics》2016,12(5)
The Huntington’s disease (HD) protein, huntingtin (HTT), is a large protein consisting of 3144 amino acids and has conserved N-terminal sequences that are followed by a polyglutamine (polyQ) repeat. Loss of Htt is known to cause embryonic lethality in mice, whereas polyQ expansion leads to adult neuronal degeneration. Whether N-terminal HTT is essential for neuronal development or contributes only to late-onset neurodegeneration remains unknown. We established HTT knock-in mice (N160Q-KI) expressing the first 208 amino acids of HTT with 160Q, and they show age-dependent HTT aggregates in the brain and neurological phenotypes. Importantly, the N-terminal mutant HTT also preferentially accumulates in the striatum, the brain region most affected in HD, indicating the importance of N-terminal HTT in selective neuropathology. That said, homozygous N160Q-KI mice are also embryonic lethal, suggesting that N-terminal HTT alone is unable to support embryonic development. Using Htt knockout neurons, we found that loss of Htt selectively affects the survival of developing neuronal cells, but not astrocytes, in culture. This neuronal degeneration could be rescued by a truncated HTT lacking the first 237 amino acids, but not by N-terminal HTT (1–208 amino acids). Also, the rescue effect depends on the region in HTT known to be involved in intracellular trafficking. Thus, the N-terminal HTT region may not be essential for the survival of developing neurons, but when carrying a large polyQ repeat, can cause selective neuropathology. These findings imply a possible therapeutic benefit of removing the N-terminal region of HTT containing the polyQ repeat to treat the neurodegeneration in HD. 相似文献
67.
68.
Tatiane Klingelfus Paula Moiana da Costa Marcos Scherer Marta Margarete Cestari 《Genetics and molecular biology》2015,38(4):499-506
Even though aluminum is the third most common element present in the earth''s crust,
information regarding its toxicity remains scarce. It is known that in certain cases,
aluminum is neurotoxic, but its effect in other tissues is unknown. The aim of this
work was to analyze the genotoxic potential of aluminum sulfate in kidney tissue of
the fish Rhamdia quelen after trophic contamination for 60 days.
Sixty four fish were subdivided into the following groups: negative control, 5 mg, 50
mg and 500 mg of aluminum sulfate per kg of fish. Samples of the posterior kidney
were taken and prepared to obtain mitotic metaphase, as well as the comet assay. The
three types of chromosomal abnormalities (CA) found were categorized as chromatid
breaks, decondensation of telomeric region, and early separation of sister
chromatids. The tests for CA showed that the 5 mg/kg and 50 mg/kg doses of aluminum
sulfate had genotoxic potential. Under these treatments, early separation of the
sister chromatids was observed more frequently and decondensation of the telomeric
region tended to increase in frequency. We suggest that structural changes in the
proteins involved in DNA compaction may have led to the decondensation of the
telomeric region, making the DNA susceptible to breaks. Moreover, early separation of
the sister chromatids may have occurred due to changes in the mobility of chromosomes
or proteins that keep the sister chromatids together. The comet assay confirmed the
genotoxicity of aluminum sulfate in the kidney tissue of Rhamdia
quelen at the three doses of exposure. 相似文献
69.
Marta Mauro-Lizcano Lorena Esteban-Martínez Esther Seco Ana Serrano-Puebla Lucia Garcia-Ledo Cláudia Figueiredo-Pereira Helena L A Vieira Patricia Boya 《Autophagy》2015,11(5):833-843
Mitochondrial autophagy, also known as mitophagy, is an autophagosome-based mitochondrial degradation process that eliminates unwanted or damaged mitochondria after cell stress. Most studies dealing with mitophagy rely on the analysis by fluorescence microscopy of mitochondrial-autophagosome colocalization. However, given the fundamental role of mitophagy in the physiology and pathology of organisms, there is an urgent need for novel quantitative methods with which to study this process. Here, we describe a flow cytometry-based approach to determine mitophagy by using MitoTracker Deep Red, a widely used mitochondria-selective probe. Used in combination with selective inhibitors it may allow for the determination of mitophagy flux. Here, we test the validity of the use of this method in cell lines and in primary cell and tissue cultures. 相似文献
70.
Claudia T Guimaraes Christiano C Simoes Maria Marta Pastina Lyza G Maron Jurandir V Magalhaes Renato CC Vasconcellos Lauro JM Guimaraes Ubiraci GP Lana Carlos FS Tinoco Roberto W Noda Silvia N Jardim-Belicuas Leon V Kochian Vera MC Alves Sidney N Parentoni 《BMC genomics》2014,15(1)