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排序方式: 共有1008条查询结果,搜索用时 31 毫秒
991.
992.
Ilaria De Pasquale Maria Calasso Leonardo Mancini Danilo Ercolini Antonietta La Storia Maria De Angelis Raffaella Di Cagno Marco Gobbetti 《Applied and environmental microbiology》2014,80(14):4085-4094
Pyrosequencing of the 16S rRNA gene, community-level physiological profiles determined by the use of Biolog EcoPlates, and proteolysis analyses were used to characterize Canestrato Pugliese Protected Designation of Origin (PDO) cheese. The number of presumptive mesophilic lactococci in raw ewes'' milk was higher than that of presumptive mesophilic lactobacilli. The numbers of these microbial groups increased during ripening, showing temporal and numerical differences. Urea-PAGE showed limited primary proteolysis, whereas the analysis of the pH 4.6-soluble fraction of the cheese revealed that secondary proteolysis increased mainly from 45 to 75 days of ripening. This agreed with the concentration of free amino acids. Raw ewes'' milk was contaminated by several bacterial phyla: Proteobacteria (68%; mainly Pseudomonas), Firmicutes (30%; mainly Carnobacterium and Lactococcus), Bacteroidetes (0.05%), and Actinobacteria (0.02%). Almost the same microbial composition persisted in the curd after molding. From day 1 of ripening onwards, the phylum Firmicutes dominated. Lactococcus dominated throughout ripening, and most of the Lactobacillus species appeared only at 7 or 15 days. At 90 days, Lactococcus (87.2%), Lactobacillus (4.8%; mainly Lactobacillus plantarum and Lactobacillus sakei), and Leuconostoc (3.9%) dominated. The relative utilization of carbon sources by the bacterial community reflected the succession. This study identified strategic phases that characterized the manufacture and ripening of Canestrato Pugliese cheese and established a causal relationship between mesophilic lactobacilli and proteolysis. 相似文献
993.
Roberta Miglio Stefano Palmery Mario Salvalaggio Lino Carnelli Federico Capuano Raffaella Borrelli 《Journal of applied phycology》2013,25(6):1621-1631
The present study aims to develop a methodology via Fourier transform infrared (FT-IR) spectroscopy for the semiquantitative determination of triacylglycerols (TAGs) in microalgal consortia, consistent with the use of the technique as process control. FT-IR spectroscopy has proved to be a powerful analytical tool for the identification of macromolecular pools (e.g., proteins, lipids, and carbohydrates) and in monitoring biochemical changes (including lipids) in response to nutrient stress or environmental modifications. In the Oocystis-based consortium under examination, the synthesis of neutral lipid in the form of TAGs can be induced, applying stress condition, and these lipids are suitable as biodiesel precursors. In the exponential growing phase, the consortium shows a low TAGs content, in the order of 5 %w, that can be increased till around 22 %w on ash free dry matter, after nitrogen starvation. 相似文献
994.
Ambrosio MR Rocca BJ Ginori A Onorati M Fabbri A Carmellini M Lazzi S Tripodi S 《Diagnostic pathology》2012,7(1):50
ABSTRACT: Angioimmunoblastic T-cell lymphoma (AITL) is one of the most common subtypes of peripheral T-cell lymphoma (15-20% of all cases), accounting for approximately 1-2% of all non-Hodgkin lymphomas. It often presents autoimmune phenomena including hemolytic anemia, thrombocytopenia, glomerulonephrities and circulating immune complexes (CIC). Polyarteritis nodosa (PAN) is an autoimmune disease characterized by necrotizing vasculitis of medium vessels, which rarely develops in association with hematological malignant disorders. Herein we report the case of a male patient with AITL who had a renal infarction secondary to PAN, mimicking a neoplastic lesion. A 40-year-old man underwent lymph node biopsy in the suspicious of sarcoidosis. On the basis of histological and immunohistochemical findings, a diagnosis of AITL was performed. The patient was successfully treated with a cytarabine-based regimen for 6 cycles. Three months after the initial diagnosis of AITL, a whole body CT-scan showed a lesion in the lower pole of the left kidney. A renal cell carcinoma was suspected, thus a nephrectomy was carried out. The histological findings were compatible with polyarteritis nodosa. To the best of our knowledge, the association between PAN and AITL has been described only once. This relation may be secondary to the induction of an autoimmune phenomenon by the lymphoma with the formation of circulating immune complexes, leading to vessel walls injury. A careful evaluation is needed in the management of AITL patients with signs of renal failure in order to avoid delay of treatment and organ damage. Key words: renal infarction, polyarteritis nodosa, T-cell lymphoma. 相似文献
995.
Anna Carfora Paola Cassandro Alessandro Feola Francesco La Sala Raffaella Petrella Renata Borriello 《Journal of bioethical inquiry》2018,15(1):45-55
Different immunotherapeutic approaches are in the pipeline for the treatment of drug dependence. “Drug vaccines” aim to induce the immune system to produce antibodies that bind to drugs and prevent them from inducing rewarding effects in the brain. Drugs of abuse currently being tested using these new approaches are opioids, nicotine, cocaine, and methamphetamine. In human clinical trials, “cocaine and nicotine vaccines” have been shown to induce sufficient antibody levels while producing few side effects. Studies in humans, determining how these vaccines interact in combination with their target drug, are underway. However, although vaccines can become a reasonable treatment option for drugs of abuse, there are several disadvantages that must be considered. These include i) great individual variability in the formation of antibodies, ii) the lack of protection against a structurally dissimilar drug that produces the same effects as the drug of choice, and iii) the lack of an effect on the drug desire that may predispose an addict to relapse. In addition, a comprehensive overview of several crucial ethical issues has not yet been widely discussed in order to have not only a biological approach to immunotherapy of addiction. Overall, immunotherapy offers a range of possible treatment options: the pharmacological treatment of addiction, the treatment of overdoses, the prevention of toxicity to the brain or the heart, and the protection of the fetus during pregnancy. So far, the results obtained from a small-scale experiment using vaccines against cocaine and nicotine suggest that a number of important technical challenges still need to be overcome before such vaccines can be approved for clinical use. 相似文献
996.
Changes in ethanol, lactate and malate content in Acer pseudoplatanus cells: effects of fusicoccin and O2 availability 总被引:1,自引:0,他引:1
Changes in the contents of ethanol, lactate and malate were determined at different activities of the plasma membrane H+ pump [in the presence and absence of fusicoccin (FC)] and at different O2 availability in cultured cells of Acer pseudoplatanus L. FC induced acidification of the medium under all tested conditions of O2 availability. At low O2 concentrations both ethanolic and lactic fermentations occurred, and FC markedly stimulated lactate production but had no effect on ethanol production. There was also a small, stimulating effect of FC on malate production. At high O2 concentrations no ethanol production was observed and lactate production was reduced. Under these conditions the stimulating effect of FC on lactate production decreased, while that on malate production increased. FC-induced synthesis of lactate and malate is interpreted as depending on the activation of lactate dehydrogenase (EC 1.1.1.27) and phosphoenolpyruvate carboxylase (EC 4.1.1.31) (alkaline pH optima), respectively, due to the alkalinization of the cytoplasmic pH resulting from the stimulation of the H+ pump by FC. These results suggest that the balance between the two pH stat systems depends on the availability of O2 . 相似文献
997.
998.
Davide Frigo Ólafur Eggertsson Angela Luisa Prendin Raffaella Dibona Lucrezia Unterholzner Marco Carrer 《Global Change Biology》2023,29(20):5896-5907
Current global change is inducing heterogeneous warming trends worldwide, with faster rates at higher latitudes in the Northern Hemisphere. Consequently, tundra vegetation is experiencing an increase in growth rate and uneven but expanding distribution. Yet, the drivers of this heterogeneity in woody species responses are still unclear. Here, applying a retrospective approach and focusing on long-term responses, we aim to get insight into growth trends and climate sensitivity of long-lived woody species belonging to different functional types with contrasting growth forms and leaf habits (shrub vs. tree and deciduous vs. evergreen). A total of 530 samples from 7 species (common juniper, dwarf birch, woolly willow, Norway spruce, lodgepole pine, rowan, and downy birch) were collected in 10 sites across Iceland. We modelled growth trends and contrasted yearly ring-width measurements, filtering in high- and low-frequency components, with precipitation, land- and sea-surface temperature records (1967–2018). Shrubs and trees showed divergent growth trends, with shrubs closely tracking the recent warming, whereas trees, especially broadleaved, showed strong fluctuations but no long-term growth trends. Secondary growth, particularly the high-frequency component, was positively correlated with summer temperatures for most of the species. On the contrary, growth responses to sea surface temperature, especially in the low frequency, were highly diverging between growth forms, with a strong positive association for shrubs and a negative for trees. Within comparable vegetation assemblage, long-lived woody species could show contrasting responses to similar climatic conditions. Given the predominant role of oceanic masses in shaping climate patterns in the Arctic and Low Arctic, further investigations are needed to deepen the knowledge on the complex interplay between coastal tundra ecosystems and land-sea surface temperature dynamics. 相似文献
999.
Alessandra Mascaro Massimo Farina Raffaella Gigli Carlo E Vitelli Lucio Fortunato 《World journal of surgical oncology》2010,8(1):1-17
A tremendous improvement in every aspect of breast cancer management has occurred in the last two decades. Surgeons, once solely interested in the extipartion of the primary tumor, are now faced with the need to incorporate a great deal of information, and to manage increasingly complex tasks. As a comprehensive assessment of all aspects of breast cancer care is beyond the scope of the present paper, the current review will point out some of these innovations, evidence some controversies, and stress the need for the surgeon to specialize in the various aspects of treatment and to be integrated into the multisciplinary breast unit team. 相似文献
1000.
Raffaella Carzaniga Marie-Charlotte Domart Lucy M. Collinson Elizabeth Duke 《Protoplasma》2014,251(2):449-458
One of the ultimate aims of imaging in biology is to achieve molecular localisation in the context of the structure of cells in their native state. Here, we review the current state of the art in cryo-soft X-ray tomography (cryo-SXT), which is the only imaging modality that can provide nanoscale 3D information from cryo-preserved, unstained, whole cells thicker than 1 μm. Correlative cryo-fluorescence and cryo-SXT adds functional information to structure, enabling studies of cellular events that cannot be captured using light, electron or X-ray microscopes alone. 相似文献