全文获取类型
收费全文 | 1011篇 |
免费 | 110篇 |
专业分类
1121篇 |
出版年
2022年 | 13篇 |
2021年 | 12篇 |
2020年 | 11篇 |
2019年 | 10篇 |
2018年 | 30篇 |
2017年 | 25篇 |
2016年 | 24篇 |
2015年 | 48篇 |
2014年 | 38篇 |
2013年 | 74篇 |
2012年 | 70篇 |
2011年 | 61篇 |
2010年 | 56篇 |
2009年 | 29篇 |
2008年 | 51篇 |
2007年 | 52篇 |
2006年 | 43篇 |
2005年 | 43篇 |
2004年 | 34篇 |
2003年 | 34篇 |
2002年 | 27篇 |
2001年 | 22篇 |
2000年 | 28篇 |
1999年 | 24篇 |
1998年 | 10篇 |
1997年 | 14篇 |
1996年 | 13篇 |
1995年 | 9篇 |
1994年 | 9篇 |
1993年 | 8篇 |
1992年 | 16篇 |
1991年 | 15篇 |
1990年 | 11篇 |
1988年 | 10篇 |
1987年 | 7篇 |
1986年 | 9篇 |
1985年 | 11篇 |
1983年 | 8篇 |
1982年 | 7篇 |
1981年 | 6篇 |
1980年 | 6篇 |
1979年 | 7篇 |
1977年 | 7篇 |
1976年 | 14篇 |
1974年 | 8篇 |
1970年 | 4篇 |
1969年 | 6篇 |
1968年 | 8篇 |
1967年 | 5篇 |
1964年 | 6篇 |
排序方式: 共有1121条查询结果,搜索用时 15 毫秒
41.
In the present work, the transported fluid and the tissue content of ATP, ADP and AMP has been evaluated in the jejunum rat intestine which was everted and incubated in vitro both at 28 degrees C and at 38 degrees C for 1 h. The energy-rich phosphates have been measured in the tissue at the beginning and at the end of the experiment as well as in vivo. These determinations have been made in the total intestine and in the scraped mucosa. ATP and ADP content are higher in vivo and lower but constant at 28 degrees C in vitro; on the contrary, at 38 degrees C in vitro, the initial and final content of these adenilic nucleotides are both lower than at 28 degrees C. Under all these conditions the AMP content does not vary appreciably. Wet weight to dry weight ratios ahve been reported for mucosal and submucosal tissues in unincubated and incubated intestines. In some experiments, fluid transport (measured as an actual serosal volume increase) was determined every 20 min during a 1-h incubation. At 28 degrees C, fluid transport is constant throughout the time of the experiment, but at 38 degrees C, there is a progressive decrease of the transported fluid. Fluid transport and ATP content of the intestine seem to be directly related. The transport activity which is lower at 38 degrees C than at 28 degrees C, seems to be due to a low availability of energy-rich phosphates. 相似文献
42.
L. Esposito P. Bifulco P. Gargiulo M.K. Gíslason M. Cesarelli L. Iuppariello 《Computer methods in biomechanics and biomedical engineering》2013,16(12):663-672
AbstractTotal Hip Arthroplasty requires pre-surgical evaluation between un-cemented and cemented prostheses. A Patient with intra-operative periprosthetic fracture and another with a successful outcome were recruited, and their finite element models were constructed by processing CT data, assuming elastic-plastic behavior of the bone as function of the local density. To resemble the insertion of the prosthesis into the femur, a fictitious thermal dilatation is applied to the broach volume. Strain-based fracture risk factor is estimated, depicting results in terms of the total mechanical strain expressed using a simple “traffic lights” color code to provide immediate, concise, and intelligible pre-operative information to surgeons. 相似文献
43.
Tiziana Genovese Emanuela Mazzon Emanuela Esposito Rosanna Di Paola Kanneganti Murthy Lewis Neville 《Free radical research》2013,47(7):631-645
The aim of the present study was to assess the effect of a metalloporphyrinic peroxynitrite decomposition catalyst, ww-85, in the pathophysiology of spinal cord injury (SCI) in mice. Spinal cord trauma was induced by the application of vascular clips to the dura via a four-level T5–T8 laminectomy. SCI in mice resulted in severe trauma characterized by oedema, neutrophil infiltration, production of inflammatory mediators, tissue damage and apoptosis. ww-85 treatment (30–300 µg/kg, i.p. 1 h after the SCI) significantly reduced in a dose-dependent manner: (1) the degree of spinal cord inflammation and tissue injury, (2) neutrophil infiltration (myeloperoxidase activity), (3) nitrotyrosine formation and PARP activation, (4) pro-inflammatory cytokines expression, (5) NF-κB activation and (6) apoptosis. Moreover, ww-85 significantly ameliorated the recovery of limb function (evaluated by motor recovery score) in a dose-dependent manner. The results demonstrate that ww-85 treatment reduces the development of inflammation and tissue injury associated with spinal cord trauma. 相似文献
44.
Daniela Impellizzeri Emanuela Esposito Rosanna Di Paola Akbar Ahmad Michela Campolo Angelo Peli Valeria Maria Morittu Domenico Britti Salvatore Cuzzocrea 《Arthritis research & therapy》2013,15(6):R192
IntroductionN-palmitoylethanolamine (PEA) is an endogenous fatty acid amide belonging to the family of the N-acylethanolamines (NAEs). Recently, several studies demonstrated that PEA is an important analgesic, antiinflammatory, and neuroprotective mediator. The aim of this study was to investigate the effect of co-ultramicronized PEA + luteolin formulation on the modulation of the inflammatory response in mice subjected to collagen-induced arthritis (CIA).MethodsCIA was induced by an intradermally injection of 100 μl of the emulsion (containing 100 μg of bovine type II collagen (CII)) and complete Freund adjuvant (CFA) at the base of the tail. On day 21, a second injection of CII in CFA was administered. Mice subjected to CIA were administered PEA (10 mg/kg 10% ethanol, intraperitoneally (i.p.)) or co-ultramicronized PEA + luteolin (1 mg/kg, i.p.) every 24 hours, starting from day 25 to 35.ResultsMice developed erosive hind-paw arthritis when immunized with CII in CFA. Macroscopic clinical evidence of CIA first appeared as periarticular erythema and edema in the hindpaws. The incidence of CIA was 100% by day 28 in the CII-challenged mice, and the severity of CIA progressed over a 35-day period with a resorption of bone. The histopathology of CIA included erosion of the cartilage at the joint. Treatment with PEA or PEA + luteolin ameliorated the clinical signs at days 26 to 35 and improved histologic status in the joint and paw. The degree of oxidative and nitrosative damage was significantly reduced in PEA + luteolin-treated mice, as indicated by nitrotyrosine and malondialdehyde (MDA) levels. Plasma levels of the proinflammatory cytokines and chemokines were significantly reduced by PEA + luteolin treatment.ConclusionsWe demonstrated that PEA co-ultramicronized with luteolin exerts an antiinflammatory effect during chronic inflammation and ameliorates CIA. 相似文献
45.
Christian Esposito Massimo Ficco Francesco Palmieri Aniello Castiglione 《Cluster computing》2013,16(4):887-903
Cloud Federation is an emerging computing model where multiple resources from independent Cloud providers are leveraged to create large-scale distributed virtual computing clusters, operating as into a single Cloud organization. This model enables the implementation of environmental diversity for Cloud applications, and overcomes the provisioning and scalability limits of a single Cloud, by introducing minimal additional cost for the Cloud consumer. In such a scenario, it is necessary to leverage on specific networking technologies that enable the effective support of inter-Cloud communication services between Cloud providers. This paper proposes an interconnection solution for Cloud federations based on publish/subscribe services. Moreover, we discuss some fundamental concerns needed to satisfy the inter-Cloud communication requirements in terms of reliability and availability. Finally, we present some experimental results that highlight some key reliability and denial of service vulnerability concerns in this domain. 相似文献
46.
Cecilia Marini Barbara Salani Michela Massollo Adriana Amaro Alessia Isabella Esposito Anna Maria Orengo Selene Capitanio Laura Emionite Mattia Riondato Gianluca Bottoni Cinzia Massara Simona Boccardo Marina Fabbi Cristina Campi Silvia Ravera Giovanna Angelini Silvia Morbelli Michele Cilli Renzo Cordera Mauro Truini Davide Maggi Ulrich Pfeffer Gianmario Sambuceti 《Cell cycle (Georgetown, Tex.)》2013,12(22):3490-3499
Emerging evidence suggests that metformin, a widely used anti-diabetic drug, may be useful in the prevention and treatment of different cancers. In the present study, we demonstrate that metformin directly inhibits the enzymatic function of hexokinase (HK) I and II in a cell line of triple-negative breast cancer (MDA-MB-231). The inhibition is selective for these isoforms, as documented by experiments with purified HK I and II as well as with cell lysates. Measurements of 18F-fluoro-deoxyglycose uptake document that it is dose- and time-dependent and powerful enough to virtually abolish glucose consumption despite unchanged availability of membrane glucose transporters. The profound energetic imbalance activates phosphorylation and is subsequently followed by cell death. More importantly, the “in vivo” relevance of this effect is confirmed by studies of orthotopic xenografts of MDA-MB-231 cells in athymic (nu/nu) mice. Administration of high drug doses after tumor development caused an evident tumor necrosis in a time as short as 48 h. On the other hand, 1 mo metformin treatment markedly reduced cancer glucose consumption and growth. Taken together, our results strongly suggest that HK inhibition contributes to metformin therapeutic and preventive potential in breast cancer. 相似文献
47.
Bradley R. Postle Edward Awh John T. Serences David W. Sutterer Mark D’Esposito 《PloS one》2013,8(12)
The positional-specificity effect refers to enhanced performance in visual short-term memory (VSTM) when the recognition probe is presented at the same location as had been the sample, even though location is irrelevant to the match/nonmatch decision. We investigated the mechanisms underlying this effect with behavioral and fMRI studies of object change-detection performance. To test whether the positional-specificity effect is a direct consequence of active storage in VSTM, we varied memory load, reasoning that it should be observed for all objects presented in a sub-span array of items. The results, however, indicated that although robust with a memory load of 1, the positional-specificity effect was restricted to the second of two sequentially presented sample stimuli in a load-of-2 experiment. An additional behavioral experiment showed that this disruption wasn’t due to the increased load per se, because actively processing a second object – in the absence of a storage requirement – also eliminated the effect. These behavioral findings suggest that, during tests of object memory, position-related information is not actively stored in VSTM, but may be retained in a passive tag that marks the most recent site of selection. The fMRI data were consistent with this interpretation, failing to find location-specific bias in sustained delay-period activity, but revealing an enhanced response to recognition probes that matched the location of that trial’s sample stimulus. 相似文献
48.
Aldo Scarpa Katarzyna Sikora Matteo Fassan Anna Maria Rachiglio Rocco Cappellesso Davide Antonello Eliana Amato Andrea Mafficini Matilde Lambiase Claudia Esposito Emilio Bria Francesca Simonato Maria Scardoni Giona Turri Marco Chilosi Giampaolo Tortora Ambrogio Fassina Nicola Normanno 《PloS one》2013,8(11)
Identification of driver mutations in lung adenocarcinoma has led to development of targeted agents that are already approved for clinical use or are in clinical trials. Therefore, the number of biomarkers that will be needed to assess is expected to rapidly increase. This calls for the implementation of methods probing the mutational status of multiple genes for inoperable cases, for which limited cytological or bioptic material is available. Cytology specimens from 38 lung adenocarcinomas were subjected to the simultaneous assessment of 504 mutational hotspots of 22 lung cancer-associated genes using 10 nanograms of DNA and Ion Torrent PGM next-generation sequencing. Thirty-six cases were successfully sequenced (95%). In 24/36 cases (67%) at least one mutated gene was observed, including EGFR, KRAS, PIK3CA, BRAF, TP53, PTEN, MET, SMAD4, FGFR3, STK11, MAP2K1. EGFR and KRAS mutations, respectively found in 6/36 (16%) and 10/36 (28%) cases, were mutually exclusive. Nine samples (25%) showed concurrent alterations in different genes. The next-generation sequencing test used is superior to current standard methodologies, as it interrogates multiple genes and requires limited amounts of DNA. Its applicability to routine cytology samples might allow a significant increase in the fraction of lung cancer patients eligible for personalized therapy. 相似文献
49.
Rossella Valentino Vittoria D’Esposito Federica Passaretti Antonietta Liotti Serena Cabaro Michele Longo Giuseppe Perruolo Francesco Oriente Francesco Beguinot Pietro Formisano 《PloS one》2013,8(12)
Current evidence indicates that chemical pollutants may interfere with the homeostatic control of nutrient metabolism, thereby contributing to the increased prevalence of metabolic disorders. Bisphenol-A (BPA) is a lipophilic compound contained in plastic which is considered a candidate for impairing energy and glucose metabolism. We have investigated the impact of low doses of BPA on adipocyte metabolic functions. Human adipocytes derived from subcutaneous adipose tissue and differentiated 3T3-L1 cells were incubated with BPA, in order to evaluate the effect on glucose utilization, insulin sensitivity and cytokine secretion. Treatment with 1nM BPA significantly inhibited insulin-stimulated glucose utilization, without grossly interfering with adipocyte differentiation. Accordingly, mRNA levels of the adipogenic markers PPARγ and GLUT4 were unchanged upon BPA exposure. BPA treatment also impaired insulin-activated receptor phosphorylation and signaling. Moreover, adipocyte incubation with BPA was accompanied by increased release of IL-6 and IFN-γ, as assessed by multiplex ELISA assays, and by activation of JNK, STAT3 and NFkB pathways. Treatment of the cells with the JNK inhibitor SP600125 almost fully reverted BPA effect on insulin signaling and glucose utilization. In conclusion, low doses of BPA interfere with inflammatory/insulin signaling pathways, leading to impairment of adipose cell function. 相似文献
50.
Irene Colavita Nicola Esposito Concetta Quintarelli Ersilia Nigro Fabrizio Pane Margherita Ruoppolo Francesco Salvatore 《Proteomics》2013,13(16):2414-2418
In the present study, we used a functional proteomic approach to identify Annexin A1 (Anxa1) interacting proteins in the Philadelphia‐positive KCL22 cell line. We focused on Anxa1 because it is one of the major proteins upregulated in imatinib‐sensitive KCL22S cells versus imatinib‐resistant KCL22R. Our proteomic strategy revealed 21 interactors. Bioinformatic analysis showed that most of these proteins are involved in cell death processes. Among the proteins identified, we studied the interaction of Anxa1 with two phosphatases, Shp1 and Shp2, which were recently identified as biomarkers of imatinib sensitivity in patients affected by chronic myeloid leukemia. Our data open new perspectives in the search for annexin‐mediated signaling pathways and may shed light on mechanisms of resistance to imatinib that are unrelated to Bcr‐Abl activity. All mass spectrometry data have been deposited in the ProteomeXchange with identifier PXD000030. 相似文献