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91.
Tiziana Comito Elena Clerici Angelo Tozzi Giuseppe D’Agostino 《Reports of Practical Oncology and Radiotherapy》2015,20(6):464-471
BackgroundThe outstanding innovations made by early diagnosis, novel surgical techniques, effective chemotherapy regimens and conformal radiotherapy, have significantly improved patients overall survival and quality of life. Multidisciplinary approach to cancer has also led to an increased prevalence of patients with few, organ-confined metastases, who can experience long-term survival even if their disease is no longer localized. Liver is one of the most common site for metastatic disease from several cancers, and when metastatic disease is confined to liver, given the ability of this organ to regenerate almost to its optimal volume, surgical resection represents the standard of care because is associated with a better prognosis. Approximately 70–90% of liver metastases, however, are unresectable and a safe, effective alternative therapeutic option is necessary for these patients.Materials and methodsA review of the current literature was performed to analyze the role of SBRT in treating liver metastases from different cancers. A literature search using the terms “SBRT” and “liver metastases” was carried out in PUBMED.ResultsStereotactic body radiation therapy has shown to provide promising results in the treatment of liver metastases, thanks to the ability of this procedure to deliver a conformal high dose of radiation to the target lesion and a minimal dose to surrounding critical tissues.ConclusionStereotactic body radiation therapy is a non-invasive, well-tolerated and effective treatment for patients with liver metastases not suitable for surgical resection. 相似文献
92.
Tafuri S Martinelli D Grimaldi A Lopatriello A Giorgio V Prato R 《The new microbiologica》2011,34(4):417-420
We report a clinical failure of a pneumococcal vaccine in a patient who developed pneumococcal pneumonia. In 2008, an 85-year-old Italian woman was admitted to the Respiratory Disease Unit of a hospital in Southern Italy. The 23-valent pneumococcal vaccine had been administered to the patient 50 days earlier. The chest x-ray disclosed a right basal bronchopneumonic focus. Streptococcus Pneumoniae serotype 19A, a strain included in the 23-valent pneumococcal vaccine, was isolated from the sputum. There is a need for more efficacious conjugated vaccines covering the majority of the pneumococcal serotypes that cause serious illness in older children and adults worldwide. 相似文献
93.
Sergio Giuffrida Rosario Troia Chiara Schiraldi Antonella D??Agostino Mario De Rosa Lorenzo Cordone 《Food biophysics》2011,6(2):217-226
Saccharide-based biopreservation is widely studied because of its scientific importance and possible technological outcomes
for food and pharmaceutical industries. Ternary protein/saccharide/water systems have been extensively exploited to model
the characteristics of the in vivo biopreservation process. A tight, water dependent, protein–matrix coupling has been shown
to occur in various simple saccharide amorphous matrices, which is stronger in trehalose. The efficiency as bioprotectant
of trehalose has been ascribed to this tight coupling, since the appearance of damages on biological structures will more
involve structural variations of the surrounding matrix. Here we present, as an applicative follow-up of this research line,
a Fourier transform infrared study on protein–matrix coupling in commercial maltodextrins and trehalosyldextrins solid amorphous
systems, with carboxymyoglobin embedded, and compare the results with analogous system containing trehalose and maltose, previously
reported. Results point out that trehalosyldextrins are useful candidates as protecting agents, even though with an efficiency
lower than trehalose, and could be used when the rheological properties of relative long-chain oligosaccharides are needed.
However, it appears that a substantial improvement could be obtained by removal of the small fraction of glucose. 相似文献
94.
Aldair JW Pinto Maria M Figueiredo Fabiana L Silva Trycia Martins Marilene SM Michalick Washington L Tafuri Wagner L Tafuri 《Acta veterinaria Scandinavica》2011,53(1):1-8
Background
A nationwide survey on the microbial etiology of cases of subclinical mastitis in dairy cows was carried out on dairy farms in Sweden. The aim was to investigate the microbial panorama and the occurrence of antimicrobial resistance. Moreover, differences between newly infected cows and chronically infected cows were investigated.Methods
In total, 583 quarter milk samples were collected from 583 dairy cows at 226 dairy farms from February 2008 to February 2009. The quarter milk samples were bacteriological investigated and scored using the California Mastitis Test. Staphylococci were tested for betalactamase production and presence of resistance was evaluated in all specific udder pathogens. Differences between newly infected cows and chronically infected cows were statistically investigated using logistic regression analysis.Results
The most common isolates of 590 bacteriological diagnoses were Staphylococcus (S) aureus (19%) and coagulase-negative staphylococci (CNS; 16%) followed by Streptococcus (Str) dysgalactiae (9%), Str. uberis (8%), Escherichia (E.) coli (2.9%), and Streptococcus spp. (1.9%). Samples with no growth or contamination constituted 22% and 18% of the diagnoses, respectively. The distribution of the most commonly isolated bacteria considering only bacteriological positive samples were: S. aureus - 31%, CNS - 27%, Str. dysgalactiae - 15%, Str. uberis - 14%, E. coli - 4.8%, and Streptococcus spp. - 3.1%. There was an increased risk of finding S. aureus, Str. uberis or Str. dysgalactiae in milk samples from chronically infected cows compared to findings in milk samples from newly infected cows. Four percent of the S. aureus isolates and 35% of the CNS isolates were resistant to penicillin G. Overall, resistance to other antimicrobials than penicillin G was uncommon.Conclusions
Staphylococcus aureus and CNS were the most frequently isolated pathogens and resistance to antimicrobials was rare. 相似文献95.
Porri A Baroncelli R Guglielminetti L Sarrocco S Guazzelli L Forti M Catelani G Valentini G Bazzichi A Franceschi M Vannacci G 《Fungal biology》2011,115(1):30-37
Degradation and detoxification of textile dyes are of interest due to the huge environmental impact of such chemicals. An isolate of Fusarium oxysporum was used to degrade and to detoxify a new chemical class of textile dyes called Glycoconjugate Azo Dye (GAD). After 6 d of growth in a liquid batch culture, the fungus degraded the dye and the culture medium at the end of incubation period showed a ?100% detoxification compared to the initial dye solution. Increasing the initial fungal inoculum, the dye was totally decolourized after 24 h of incubation. The degradation ability was found to be common among various isolates of F. oxysporum suggesting this as a specific trait of this species. Degrading rate was enhanced in concomitancy to the glucose depletion and the beginning of the stationary phase of growth, suggesting that the shift from the primary to the secondary metabolism may be the trigger of the degradation pathway. The Daphnia magna acute toxicity test demonstrated a strong detoxification of GAD-4 by F. oxysporum, resulting in non-toxic metabolite production. Fusarium oxysporum could, therefore, be taken into consideration to develop new remediation strategies of textile effluents. 相似文献
96.
Cristina Gervasoni Paola Meraviglia Simona Landonio Sara Baldelli Serena Fucile Laura Castagnoli Emilio Clementi Agostino Riva Massimo Galli Giuliano Rizzardini Dario Cattaneo 《PloS one》2013,8(12)
Treatment with tenofovir sometimes leads to non-reversible kidney and/or bone diseases. Factors associated with these drug-related adverse events are poorly characterized. Our objective was to investigate such factors in patients treated long term with daily tenofovir. One-hundred Caucasian HIV-positive patients with basal creatinine clearance >80 mL/min treated with tenofovir for at least 6 months and with at least one assessment of tenofovir plasma trough concentrations were considered. Tenofovir-associated adverse events were defined as the appearance of pathological proteinuria, worsening of renal function or bone demineralization. By multivariate regression analysis, we found that serum creatinine (p = 0.003) and body weight (p = 0.002) were the factors independently associated with plasma tenofovir concentrations. In particular, women with body weight<50 kg had significantly higher plasma tenofovir concentrations than those weighting >50 Kg (160±93 vs.71±52 ng/mL, p<0.001). High tenofovir plasma trough concentrations and the age of the patients were independently associated with the development of drug-related kidney and bone toxicity. In this retrospective study we have shown that HIV-infected women with low body weight are at risk to be exposed to high tenofovir plasma trough concentrations, ultimately resulting in a significant hazard to develop long-term tenofovir complications. 相似文献
97.
Docking is a computational technique that places a small molecule (ligand) in the binding site of its macromolecular target (receptor) and estimates its binding affinity. This review addresses methodological developments that have occurred in the docking field in 2009, with a particular focus on the more difficult, and sometimes controversial, aspects of this promising computational discipline. These developments aim to address the main challenges of docking: receptor representation (such aspects as structural waters, side chain protonation, and, most of all, flexibility (from side chain rotation to domain movement)), ligand representation (protonation, tautomerism and stereoisomerism, and the effect of input conformation), as well as accounting for solvation and entropy of binding. This review is strongly focused on docking advances in the context of drug design, specifically in virtual screening and fragment-based drug design. 相似文献
98.
99.
Mapelli F Marasco R Rizzi A Baldi F Ventura S Daffonchio D Borin S 《Microbial ecology》2011,61(2):438-447
In arctic glacier moraines, bioweathering primed by microbial iron oxidizers creates fertility gradients that accelerate soil
development and plant establishment. With the aim of investigating the change of bacterial diversity in a pyrite-weathered
gradient, we analyzed the composition of the bacterial communities involved in the process by sequencing 16S rRNA gene libraries
from different biological soil crusts (BSC). Bacterial communities in three BSC of different morphology, located within 1 m
distance downstream a pyritic conglomerate rock, were significantly diverse. The glacier moraine surrounding the weathered
site showed wide phylogenetic diversity and high evenness with 15 represented bacterial classes, dominated by Alphaproteobacteria
and pioneer Cyanobacteria colonizers. The bioweathered area showed the lowest diversity indexes and only nine bacterial families,
largely dominated by Acidobacteriaceae and Acetobacteraceae typical of acidic environments, in accordance with the low pH of the BSC. In the weathered BSC, iron-oxidizing bacteria were
cultivated, with counts decreasing along with the increase of distance from the rock, and nutrient release from the rock was
revealed by environmental scanning electron microscopy-energy dispersive X-ray analyses. The vegetated area showed the presence
of Actinomycetales, Verrucomicrobiales, Gemmatimonadales, Burkholderiales, and Rhizobiales, denoting a bacterial community typical of developed soils and indicating that the lithoid substrate of the bare moraine
was here subjected to an accelerated colonization, driven by iron-oxidizing activity. 相似文献
100.
Analysis of hepatitis C virus hypervariable region 1 sequence from cryoglobulinemic patients and associated controls
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Bianchettin G Bonaccini C Oliva R Tramontano A Cividini A Casato M Merlini G Silini E Mondelli MU 《Journal of virology》2007,81(9):4564-4571
Chronic hepatitis C virus (HCV) infection is frequently associated with extrahepatic manifestations, including nonmalignant and malignant B-cell lymphoproliferative disorders. It has been reported that specific changes or recurring motifs in the amino acid sequence of the HCV hypervariable region 1 (HVR1) may be associated with cryoglobulinemia. We searched for specific insertions/deletions and/or amino acid motifs within HVR1 in samples from 80 symptomatic and asymptomatic patients with and 33 patients without detectable cryoglobulins, all with chronic HCV infection. At variance with the results of a previous study which reported a high frequency of insertions at position 385 of HVR1 from cryoglobulinemic patients, we found a 6.2% prevalence of insertions in samples from patients with and a 9.1% prevalence in those without cryoglobulinemia. Moreover, statistical and bioinformatics approaches including Fisher's exact test, k-means clustering, Tree determinant-residue identification, correlation of mutations, principal component analysis, and phylogenetic analysis failed to show statistically significant differences between sequences from cryoglobulin-negative and -positive patients. Our findings suggest that cryoglobulinemia may arise by virtue of as-yet-unidentified host- rather than virus-specific factors. Specific changes in HCV envelope sequence distribution are unlikely to be directly involved in the establishment of pathological B-cell monoclonal proliferation. 相似文献