全文获取类型
收费全文 | 1176篇 |
免费 | 70篇 |
出版年
2023年 | 3篇 |
2022年 | 6篇 |
2021年 | 10篇 |
2020年 | 6篇 |
2019年 | 15篇 |
2018年 | 22篇 |
2017年 | 19篇 |
2016年 | 30篇 |
2015年 | 49篇 |
2014年 | 44篇 |
2013年 | 84篇 |
2012年 | 89篇 |
2011年 | 97篇 |
2010年 | 69篇 |
2009年 | 57篇 |
2008年 | 76篇 |
2007年 | 63篇 |
2006年 | 77篇 |
2005年 | 74篇 |
2004年 | 67篇 |
2003年 | 55篇 |
2002年 | 40篇 |
2001年 | 21篇 |
2000年 | 6篇 |
1999年 | 9篇 |
1998年 | 7篇 |
1997年 | 7篇 |
1996年 | 8篇 |
1995年 | 4篇 |
1994年 | 3篇 |
1993年 | 7篇 |
1992年 | 8篇 |
1991年 | 8篇 |
1989年 | 12篇 |
1988年 | 7篇 |
1987年 | 8篇 |
1986年 | 3篇 |
1985年 | 3篇 |
1983年 | 6篇 |
1982年 | 3篇 |
1981年 | 5篇 |
1980年 | 5篇 |
1979年 | 6篇 |
1978年 | 10篇 |
1977年 | 5篇 |
1974年 | 6篇 |
1972年 | 4篇 |
1970年 | 4篇 |
1969年 | 3篇 |
1968年 | 3篇 |
排序方式: 共有1246条查询结果,搜索用时 15 毫秒
61.
Federica Zito Marino Giuseppina Liguori Gabriella Aquino Elvira La Mantia Silvano Bosari Stefano Ferrero Lorenzo Rosso Gabriella Gaudioso Nicla De Rosa Marianna Scrima Nicola Martucci Antonello La Rocca Nicola Normanno Alessandro Morabito Gaetano Rocco Gerardo Botti Renato Franco 《PloS one》2015,10(10)
62.
Angelo Campanozzi Sonia Avallone Antonio Barbato Roberto Iacone Ornella Russo Gianpaolo De Filippo Giuseppina D’Angelo Licia Pensabene Basilio Malamisura Gaetano Cecere Maria Micillo Ruggiero Francavilla Anna Tetro Giuliano Lombardi Lisa Tonelli Giuseppe Castellucci Luigi Ferraro Rita Di Biase Antonella Lezo Silvia Salvatore Silvia Paoletti Alfonso Siani Daniela Galeone Pasquale Strazzullo MINISAL-GIRCSI Program Study Group 《PloS one》2015,10(4)
Background
Hypertension is the leading cause of death in developed countries and reduction of salt intake is recommended as a key preventive measure.Objective
To assess the dietary sodium and potassium intakes in a national sample of Italian children and adolescents and to examine their relationships with BMI and blood pressure (BP) in the framework of the MINISAL survey, a program supported by the Italian Ministry of Health.Population and Methods
The study population included 1424 healthy subjects (766 boys, 658 girls) aged 6-18 years (mean age: 10.1±2.9) who were consecutively recruited in participating National Health Service centers in 10 Italian regions. Electrolyte intake was estimated from 24 hour urine collections tested for completeness by the concomitant measurement of creatinine content. Anthropometric indices and BP were measured with standardized procedures.Results
The average estimated sodium intake was 129 mmol (7.4 g of salt) per day among boys and 117 mmol (6.7 g of salt) among girls. Ninety-three percent of the boys and 89% of the girls had a consumption higher than the recommended age-specific standard dietary target. The estimated average daily potassium intakes were 39 mmol (1.53 g) and 36 mmol (1.40 g), respectively, over 96% of the boys and 98% of the girls having a potassium intake lower than the recommended adequate intake. The mean sodium/potassium ratio was similar among boys and girls (3.5 and 3.4, respectively) and over 3-fold greater than the desirable level. Sodium intake was directly related to age, body mass and BP in the whole population.Conclusions
The Italian pediatric population is characterized by excessive sodium and deficient potassium intake. These data suggest that future campaigns should focus on children and adolescents as a major target in the framework of a population strategy of cardiovascular prevention. 相似文献63.
Virginia Sciacca Francesco Caruso Laura Beranzoli Francesco Chierici Emilio De Domenico Davide Embriaco Paolo Favali Gabriele Giovanetti Giuseppina Larosa Giuditta Marinaro Elena Papale Gianni Pavan Carmelo Pellegrino Sara Pulvirenti Francesco Simeone Salvatore Viola Giorgio Riccobene 《PloS one》2015,10(11)
In recent years, an increasing number of surveys have definitively confirmed the seasonal presence of fin whales (Balaenoptera physalus) in highly productive regions of the Mediterranean Sea. Despite this, very little is yet known about the routes that the species seasonally follows within the Mediterranean basin and, particularly, in the Ionian area. The present study assesses for the first time fin whale acoustic presence offshore Eastern Sicily (Ionian Sea), throughout the processing of about 10 months of continuous acoustic monitoring. The recording of fin whale vocalizations was made possible by the cabled deep-sea multidisciplinary observatory, “NEMO-SN1”, deployed 25 km off the Catania harbor at a depth of about 2,100 meters. NEMO-SN1 is an operational node of the European Multidisciplinary Seafloor and water-column Observatory (EMSO) Research Infrastructure. The observatory was equipped with a low-frequency hydrophone (bandwidth: 0.05 Hz–1 kHz, sampling rate: 2 kHz) which continuously acquired data from July 2012 to May 2013. About 7,200 hours of acoustic data were analyzed by means of spectrogram display. Calls with the typical structure and patterns associated to the Mediterranean fin whale population were identified and monitored in the area for the first time. Furthermore, a background noise analysis within the fin whale communication frequency band (17.9–22.5 Hz) was conducted to investigate possible detection-masking effects. The study confirms the hypothesis that fin whales are present in the Ionian Sea throughout all seasons, with peaks in call detection rate during spring and summer months. The analysis also demonstrates that calls were more frequently detected in low background noise conditions. Further analysis will be performed to understand whether observed levels of noise limit the acoustic detection of the fin whales vocalizations, or whether the animals vocalize less in the presence of high background noise. 相似文献
64.
Dexamethasone‐loaded biopolymeric nanoparticles promote gingival fibroblasts differentiation 下载免费PDF全文
Laura Chronopoulou Adriana Amalfitano Cleofe Palocci Giuseppina Nocca Cinzia Callà Alessandro Arcovito 《Biotechnology progress》2015,31(5):1381-1387
Polymer‐based nanoparticles (NPs) can be efficiently used for the delivery of bioactive molecules for both in vitro and in vivo applications affording high drug loading and controlled release profiles. Within this framework polylactic‐co‐glycolic acid (PLGA) NPs with a diameter of 290 ± 41 nm have been fabricated and loaded with dexamethasone (DXM) using a patented procedure. The aim of the project was to setup a controlled delivery system to promote the in vitro differentiation of Human Gingival Fibroblasts (HGFs). First the uptake of fluorescent PLGA NPs by HGFs cells was investigated; then experiments were also addressed to analyze the specific cell response to DXM, in order to evaluate its functional efficiency in comparison with its conventional addition to the culture medium. The results showed that cells treated with DXM‐loaded NPs acquired the osteoblast phenotype faster in comparison to those treated with the free drug. The slow and sustained release of DXM from PLGA NPs produced a constant and uniform concentration of drug inside cells with long‐term and enhanced biochemical effects. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:1381–1387, 2015 相似文献
65.
Paolo Cossu-Rocca Sandra Orrù Maria Rosaria Muroni Francesca Sanges Giovanni Sotgiu Sara Ena Giovanna Pira Luciano Murgia Alessandra Manca Maria Gabriela Uras Maria Giuseppina Sarobba Silvana Urru Maria Rosaria De Miglio 《PloS one》2015,10(11)
Background
Triple Negative Breast Cancer (TNBC) accounts for 12–24% of all breast carcinomas, and shows worse prognosis compared to other breast cancer subtypes. Molecular studies demonstrated that TNBCs are a heterogeneous group of tumors with different clinical and pathologic features, prognosis, genetic-molecular alterations and treatment responsivity. The PI3K/AKT is a major pathway involved in the regulation of cell survival and proliferation, and is the most frequently altered pathway in breast cancer, apparently with different biologic impact on specific cancer subtypes. The most common genetic abnormality is represented by PIK3CA gene activating mutations, with an overall frequency of 20–40%. The aims of our study were to investigate PIK3CA gene mutations on a large series of TNBC, to perform a wider analysis on genetic alterations involving PI3K/AKT and BRAF/RAS/MAPK pathways and to correlate the results with clinical-pathologic data.Materials and Methods
PIK3CA mutation analysis was performed by using cobas® PIK3CA Mutation Test. EGFR, AKT1, BRAF, and KRAS genes were analyzed by sequencing. Immunohistochemistry was carried out to identify PTEN loss and to investigate for PI3K/AKT pathways components.Results
PIK3CA mutations were detected in 23.7% of TNBC, whereas no mutations were identified in EGFR, AKT1, BRAF, and KRAS genes. Moreover, we observed PTEN loss in 11.3% of tumors. Deregulation of PI3K/AKT pathways was revealed by consistent activation of pAKT and p-p44/42 MAPK in all PIK3CA mutated TNBC.Conclusions
Our data shows that PIK3CA mutations and PI3K/AKT pathway activation are common events in TNBC. A deeper investigation on specific TNBC genomic abnormalities might be helpful in order to select patients who would benefit from current targeted therapy strategies. 相似文献66.
Flávio Teles Tarcilo Machado da Silva Francisco Pessoa da Cruz Júnior Vitor Hugo Honorato Henrique de Oliveira Costa Ana Paula Fernandes Barbosa Sabrina Gomes de Oliveira Zenaldo Porfírio Alexandre Braga Libório Raquel Lerner Borges Camilla Fanelli 《PloS one》2015,10(1)
The pathogenic role of inflammation and oxidative stress in chronic kidney disease (CKD) is well known. Anti-inflammatories and antioxidant drugs has demonstrated significant renoprotection in experimental nephropathies. Moreover, the inclusion of natural antioxidants derived from food and herbal extracts (such as polyphenols, curcumin and lycopene) as an adjuvant therapy for slowing CKD progression has been largely tested. Brazilian propolis is a honeybee product, whose anti-inflammatory, antimicrobial and antioxidant effects have been widely shown in models of sepsis, cancer, skin irritation and liver fibrosis. Furthermore, previous studies demonstrated that this compound promotes vasodilation and reduces hypertension. However, potential renoprotective effects of propolis in CKD have never been investigated. The aim of this study was to evaluate the effects of a subtype of Brazilian propolis, the Red Propolis (RP), in the 5/6 renal ablation model (Nx). Adult male Wistar rats underwent Nx and were divided into untreated (Nx) and RP-treated (Nx+RP) groups, after 30 days of surgery; when rats already exhibited marked hypertension and proteinuria. Animals were observed for 90 days from the surgery day, when Nx+RP group showed significant reduction of hypertension, proteinuria, serum creatinine retention, glomerulosclerosis, renal macrophage infiltration and oxidative stress, compared to age-matched untreated Nx rats, which worsened progressively over time. In conclusion, RP treatment attenuated hypertension and structural renal damage in Nx model. Reduction of renal inflammation and oxidative stress could be a plausible mechanism to explain this renoprotection. 相似文献
67.
Daniele Amadio Filomena Fezza Giuseppina Catanzaro Ottaviano Incani Guus van Zadelhoff Alessandro Finazzi Agrò Mauro Maccarrone 《Biochimie》2010
The biological activity of endocannabinoids like anandamide (AEA) and 2-arachidonoylglycerol (2-AG) is subjected in vivo to a “metabolic control”, exerted mainly by catabolic enzymes. AEA is inactivated by fatty acid amide hydrolase (FAAH), that is inhibited competitively by hydroxyanandamides (HAEAs) generated from AEA by lipoxygenase activity. Among these derivatives, 15-HAEA has been shown to be an effective (Ki ∼0.6 μM) FAAH inhibitor, that blocks also type-1 cannabinoid receptor (CB1R) but not other components of the “endocannabinoid system (ECS)”, like the AEA transporter (AMT) or CB2R. Here, we extended the study of the effect of 15-HAEA on the AEA synthetase (NAPE-PLD) and the AEA-binding vanilloid receptor (TRPV1), showing that 15-HAEA activates the former (up to ∼140% of controls) and inhibits the latter protein (down to ∼70%). We also show that 15-HAEA halves the synthesis of 2-AG and almost doubles the transport of this compound across the membrane. In addition, we synthesized methyl and acetyl derivatives of 15-HAEA (15-MeOAEA and 15-AcOAEA, respectively), in order to check their ability to modulate FAAH and the other ECS elements. In fact, methylation and acetylation are common biochemical reactions in the cellular environment. We show that 15-MeOAEA, unlike 15-AcOAEA, is still a powerful competitive inhibitor of FAAH (Ki ∼0.7 μM), and that both derivatives have negligible interactions with the other proteins of ECS. Therefore, 15-MeOAEA is a FAAH inhibitor more selective than 15-HAEA. Further molecular dynamics analysis gave clues to the molecular requirements for the interaction of 15-HAEA and 15-MeOAEA with FAAH. 相似文献
68.
M. Giovanna Parisi Matteo Cammarata Gigliola Benenati Giuseppina Salerno Valentina Mangano Aiti Vizzini Nicolò Parrinello 《Cell and tissue research》2010,341(2):279-288
The purification, cloning, sequencing, molecular properties and expression of a fucose-binding lectin from the serum of Dicentrarchus labrax (DlFBL) have been previously reported. We now describe the distribution and expression of DlFBL during fish ontogeny. Immunohistochemistry
and in situ hybridization assays were carried out at various developmental stages (from 10 days post-hatching larvae to juveniles).
Another fucose-binding lectin, similar to DlFBL in biochemical, immunochemical and agglutinating properties, was extracted
and purified from eggs and appeared to be localized in the embryo yolk sack residual. DlFBL was found in columnar and goblet
cells of the intestinal epithelium of larvae (from 20 days post-hatching) and juveniles and in parenchymal tissue of juveniles.
DlFBL mRNA and protein were detected in the intestinal epithelium and in hepatocytes. An amplification product from degenerate
primers indicates that lectin isotypes with DlFBL epitopes are expressed in eggs and embryos. Whether the lectin fraction
isolated from eggs and embryos includes DlFBL of maternal origin remains unclear. 相似文献
69.
Andrea Franzetti Isabella Gandolfi Marco Piscitello Giovanni Porto Adriano Biasiolo Francesca Oltolini Tomaso Marangoni Giuseppina Bestetti 《Biodegradation》2010,21(2):193-201
The effectiveness of biosparging to mitigate N,N diethylaniline in aquifer was evaluated by measuring the time course of decrease in concentration of the aforementioned compound
in aerobic microcosm experiments. The first-order kinetic constant for N,N diethylaniline aerobic biodegradation was estimated from microcosm data (0.037 ± 0.004 d−1), and the value was consistent with the best-fitting value in the transport and reaction model of the aquifer (0.020 d−1). Furthermore, the biodegradability of the compound was evaluated under anaerobic condition in microcosm experiments, which
was supported by field modelling. There was no significant degradation in the anaerobic microcosm experiments, confirming
the recalcitrance of N,N diethyl aniline under the aforementioned aquifer condition. 相似文献
70.