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21.
Bartolini B Chillemi G Abbate I Bruselles A Rozera G Castrignanò T Paoletti D Picardi E Desideri A Pesole G Capobianchi MR 《The new microbiologica》2011,34(4):391-397
De novo high-throughput pyrosequencing was used to detect and characterize 2009 pandemic influenza A (H1N1) virus directly in nasopharyngeal swabs in the context of the microbial community. Data were generated with a prior sequence independent amplification by 454 pyrosequencing on GS-FLX platform (Roche). Influenza A assembled reads allowed near full-length genome reconstruction with the simultaneous analysis of site-specific heterogeneity. The molecular approach applied proved to be a powerful tool to characterize the new pandemic H1N1 influenza virus in clinical samples. This approach could be of great value in identifying possibly new reassortants that may occur in the near future. 相似文献
22.
Soares CR Glezer A Okazaki K Ueda EK Heller SR Walker AM Goffin V Bartolini P 《Protein expression and purification》2006,48(2):182-194
The synthesis, purification and characterization of G129R-hPRL and S179D-hPRL, the two better-studied antagonists of human prolactin (hPRL), is described. Both of these have been expressed for the first time, in their authentic form, by a stable CHO cell line, at secretion levels of 7.7 and 4.3 microg/10(6) cells/day, respectively. Previous studies had shown that these hPRL analogs, when produced in bacterial cytoplasm, consistently contained misfolded forms and multimers according to the specific denaturation, refolding and purification conditions. These versions also have an N-terminal extra methionine. An extensive physico-chemical characterization was carried out after a practical two-step purification process and included SDS-PAGE and Western blotting analysis, matrix-assisted laser-desorption ionization time-of-flight mass spectral (MALDI-TOF-MS) analysis, high-performance size-exclusion chromatography (HPSEC) and reversed-phase high-performance liquid chromatography (RP-HPLC). This last technique revealed a considerable difference in hydrophobicity due to a single amino acid substitution, with S179D-hPRL less (t(RR) = 0.85 +/- 0.010) and G129R-hPRL more (t(RR) = 1.10 +/- 0.013) hydrophobic than hPRL, where t(RR) is the relative retention time. The biological characterization was based on further refinement of a sensitive proliferation assay using the pro-B murine cell line (Ba/F3) transfected with the long form hPRL receptor cDNA such that the minimal detectable dose was 0.04 ng of hPRL/mL, the Ba/F3-LLP assay. On the basis of this assay, the relative residual agonistic activity of these two products, determined against a hPRL international standard in four independent assays, was 53 x 10(-3) for S179D-hPRL and 70 x 10(-5) for G129R-hPRL. We believe that the present synthesis and characterization could be extremely helpful for studies of these two proteins, which have been reported to antagonize tumor growth-promoting effects of hPRL in vivo in animal models of breast and prostate cancer. 相似文献
23.
Anders Malmstr?m Barbara Bartolini Martin A. Thelin Benny Pacheco Marco Maccarana 《The journal of histochemistry and cytochemistry》2012,60(12):916-925
The ability of chondroitin/dermatan sulfate (CS/DS) to convey biological information is
enriched by the presence of iduronic acid. DS-epimerases 1 and 2 (DS-epi1 and 2), in
conjunction with DS-4-O-sulfotransferase 1, are the enzymes responsible for iduronic acid
biosynthesis and will be the major focus of this review. CS/DS proteoglycans (CS/DS-PGs)
are ubiquitously found in connective tissues, basement membranes, and cell surfaces or are
stored intracellularly. Such wide distribution reflects the variety of biological roles in
which they are involved, from extracellular matrix organization to regulation of processes
such as proliferation, migration, adhesion, and differentiation. They play roles in
inflammation, angiogenesis, coagulation, immunity, and wound healing. Such versatility is
achieved thanks to their variable composition, both in terms of protein core and the fine
structure of the CS/DS chains. Excellent reviews have been published on the collective and
individual functions of each CS/DS-PG. This short review presents the biosynthesis and
functions of iduronic acid-containing structures, also as revealed by the analysis of the
DS-epi1- and 2-deficient mouse models. 相似文献
24.
Francesca Bartolini Nagendran Ramalingam Gregg G. Gundersen 《Molecular biology of the cell》2012,23(20):4032-4040
In migrating fibroblasts, RhoA and its effector mDia1 regulate the selective stabilization of microtubules (MTs) polarized in the direction of migration. The conserved formin homology 2 domain of mDia1 is involved both in actin polymerization and MT stabilization, and the relationship between these two activities is unknown. We found that latrunculin A (LatA) and jasplakinolide, actin drugs that release mDia1 from actin filament barbed ends, stimulated stable MT formation in serum-starved fibroblasts and caused a redistribution of mDia1 onto MTs. Knockdown of mDia1 by small interfering RNA (siRNA) prevented stable MT induction by LatA, whereas blocking upstream Rho or integrin signaling had no effect. In search of physiological regulators of mDia1, we found that actin-capping protein induced stable MTs in an mDia1-dependent manner and inhibited the translocation of mDia on the ends of growing actin filaments. Knockdown of capping protein by siRNA reduced stable MT levels in proliferating cells and in starved cells stimulated with lysophosphatidic acid. These results show that actin-capping protein is a novel regulator of MT stability that functions by antagonizing mDia1 activity toward actin filaments and suggest a novel form of actin–MT cross-talk in which a single factor acts sequentially on actin and MTs. 相似文献
25.
Background
Burkholderia pseudomallei is a saprophyte in tropical environments and an opportunistic human pathogen. This versatility requires a sensing mechanism that allows the bacterium to respond rapidly to altered environmental conditions. We characterized a two-component signal transduction locus from B. pseudomallei 204, mrgR and mrgS, encoding products with extensive homology with response regulators and histidine protein kinases of Escherichia coli, Bordetella pertussis, and Vibrio cholerae. 相似文献26.
Mario La Mesa Emilio Riginella Valentina Melli Fabrizio Bartolini Carlotta Mazzoldi 《Polar Biology》2016,39(1):103-111
The rock cod Patagonotothen ramsayi (Regan 1913) is the most abundant species of the genus Patagonotothen, occurring along the Patagonian shelf. It plays an important role in the demersal food web both as prey and predator, showing an increasing importance for the local finfish and squid trawl fisheries. Age structure and the reproductive traits were investigated from the population inhabiting the eastern shelf of Burdwood Bank, which represents the southernmost area of its geographical distribution. Adult specimens of P. ramsayi were collected during bottom trawling carried out in the austral summer. The specimens were aged by otolith readings, and their reproductive characteristics were assessed by macroscopical and histological analyses. Age was similar between sexes, ranging from 4 to 7 and from 4 to 8 years in males and females of comparable size, respectively. GSI was relatively low in females (<1.5 %), as fish were sampled far from the reported spawning season (June–August). Females were all in the early developing stage (III) on the macroscopic maturity scale, with the most advanced oocytes being in early vitellogenesis. The oocyte size distribution was bi-modal, with two partially overlapping modes consisting of oocytes of a maximum size of 0.66 mm. A few large atretic oocytes (diameter > 1 mm) were found in three females. Absolute fecundity ranged from approximately 30 to 120 thousands of eggs. No relationship was found between female size and fecundity, probably due to the relatively narrow range of the investigated fish sizes. Males were in the spent (VII) or resting (II) stages. 相似文献
27.
AB Johan Groeneveld 《BMC anesthesiology》2007,7(1):1-8
We have developed a two-step procedure for preparing the skin before peripheral venous catheter (PVC) insertions. This procedure involves two successive swabbings with wipes soaked in alcoholic antiseptic. We investigated whether this two-step procedure was as effective and safe as the standard four-step procedure – washing with detergent, rinsing, drying, applying antiseptic – by carrying out a multicentre randomised equivalence study comparing the frequency of precursor signs of infection at the site of insertion for the two skin preparation procedures. The study was carried out over an eight-month period, and 248 PVC insertion sites were evaluated. The two-step procedure was used for 130 subjects and the standard procedure for 118. Taking into account all the confounding factors predisposing patients to the complications studied, the characteristics of the two groups of patients were found to be similar, with no significant differences noted. The incidence of precursor signs of infection was 11 % 24 hours after PVC insertion (27/248), 25 % at 48 hours (50/203) and at 29 % at 72 hours (34/119). Eleven patients had complications necessitating the withdrawal of the PVC: sensitivity of the insertion site, with redness and/or slight swelling and/or a palpable venous cord. No major complications were observed in this study. The frequency of local complications associated with PVCs reported in this study, whether simple or severe, was not affected by the skin preparation procedure used for PVC insertion (two-step or four-step procedure). 相似文献
28.
AB Chang NC Cox J Purcell JM Marchant PJ Lewindon GJ Cleghorn LC Ee GD Withers MK Patrick J Faoagali 《Respiratory research》2005,6(1):1-5
Background and methods
Human metapneumovirus (hMPV) is a recently discovered respiratory virus associated with bronchiolitis, pneumonia, croup and exacerbations of asthma. Since respiratory viruses are frequently detected in patients with acute exacerbations of COPD (AE-COPD) it was our aim to investigate the frequency of hMPV detection in a prospective cohort of hospitalized patients with AE-COPD compared to patients with stable COPD and to smokers without by means of quantitative real-time RT-PCR.Results
We analysed nasal lavage and induced sputum of 130 patients with AE-COPD, 65 patients with stable COPD and 34 smokers without COPD. HMPV was detected in 3/130 (2.3%) AE-COPD patients with a mean of 6.5 × 105 viral copies/ml in nasal lavage and 1.88 × 105 viral copies/ml in induced sputum. It was not found in patients with stable COPD or smokers without COPD.Conclusion
HMPV is only found in a very small number of patients with AE-COPD. However it should be considered as a further possible viral trigger of AE-COPD because asymptomatic carriage is unlikely. 相似文献29.
Annamaria Leccese Raffaella Viti Susanna Bartolini 《Central European Journal of Biology》2011,6(2):199-204
Two solvent extraction procedures were used to investigate the extraction efficiency in terms of total antioxidant capacity
and total phenols in apricot fruit. Samples were either sequentially extracted with aqueous ethanol (ethanol/water 80% v/v)
and tetrahydrofuran or directly extracted with tetrahydrofuran. Each extract was analyzed for total antioxidant capacity by
the Trolox Equivalent Antioxidant Capacity (TEAC) assay and total phenols by the Folin-Ciocalteu assay. The results showed
that using sequential solvent extraction, the majority (85%) of the total antioxidant capacity and total phenols was due to
hydrophilic compounds. In tetrahydrofuran direct extractions, the total antioxidant capacity and total phenols were higher
than values obtained with aqueous ethanol and the sum of results obtained from sequential extracts for either total antioxidant
capacity or total phenols was similar to the tetrahydrofuran-extract antioxidant values. A linear correlation between total
antioxidant capacity and total phenols was found and was independent of the solvent extraction method. In conclusion, the
choice of solvent is related to the antioxidant potential of fruit and depends on the food hydrophilic/lipophilic composition. 相似文献
30.
G Bartolini M Orlandi M Chiricolo L Minghetti F Guerrini M Fidan C Franceschi V Tomasi 《Biochimica et biophysica acta》1986,876(3):486-493
It has previously been shown that platelet-free human monocytes, when properly incubated in the presence of animal and human sera, became capable of producing large amounts of thromboxane A2 and prostaglandin E2. The characteristics of these processes are reported here. Prostaglandin biosynthesis was time and cell concentration dependent; 24 h of incubation at 37 degrees C and 0.5 X 10(6) cells per ml medium were found to give the most reproducible results. Human monocytes produced thromboxane A2 and prostaglandin E2 in a typical ratio which ranged from 2.0 to 5.0 (28 experiments). Animal and human sera were similarly effective, while serum obtained from platelet-free blood was much less active. The activity of all sera tested was stable to heating (100 degrees C for 2-10 min) and extreme pH values (pH 2 and 11). It was unstable when the serum was heated at pH 11 and after 2-mercaptoethanol treatment. These observations prompted us to check the effect of polypeptide growth factors having properties similar to those reported above, such as platelet-derived growth factor, fibroblast growth factor, epidermal growth factor as well as insulin and transferrin. None of these, alone or in various combinations, was capable of eliciting a stimulation comparable with that of serum. Stimulation due to sera was, as expected, dose dependently inhibited by acetylsalicylic acid and more efficiently by indomethacin; unexpectedly it was also inhibited by protein synthesis inhibitors such as actinomycin D and cycloheximide in conditions under which no toxic effect of the drugs was evident. On the basis of these results we conclude that: (a) polypeptide growth factor(s) with a molecular weight at least 30 000 (as judged by Amicon ultrafiltration) is involved in the regulation of prostaglandin biosynthesis); (b) such a factor(s) acts by inducing rather than by activating the cyclooxygenase system. 相似文献