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981.
982.
Thevelein JM Cauwenberg L Colombo S De Winde JH Donation M Dumortier F Kraakman L Lemaire K Ma P Nauwelaers D Rolland F Teunissen A Van Dijck P Versele M Wera S Winderickx J 《Enzyme and microbial technology》2000,26(9-10):819-825
Yeast cells growing in the presence of glucose or a related rapidly-fermented sugar differ strongly in a variety of physiological properties compared to cells growing in the absence of glucose. Part of these differences appear to be caused by the protein kinase A (PKA) and related signal transduction pathways. Addition of glucose to cells previously deprived of glucose triggers cAMP accumulation, which is apparently mediated by the Gpr1-Gpa2 G-protein coupled receptor system. However, the resulting effect on PKA-controlled properties is only transient when there is no complete growth medium present. When an essential nutrient is lacking, the cells arrest in the stationary phase G0. At the same time they acquire all characteristics of cells with low PKA activity, even if there is ample glucose present. When the essential nutrient is added again, a similar PKA-dependent protein phosphorylation cascade is triggered as observed after addition of glucose to glucose-deprived cells, but which is not cAMP-mediated. Because the pathway involved requires a fermentable carbon source and a complete growth medium, at least for its sustained activation, it has been called “fermentable growth medium (FGM)-induced pathway.” 相似文献
983.
984.
Sheiban I Dharmadhikari A Tzifos V Marsico F Leonardo F Rosano G Montorfano M Pagnotta P Di Mario C Colombo A 《International journal of cardiovascular interventions》2000,3(2):105-110
BACKGROUND: Although chronic total occlusions are encountered frequently in patients with coronary artery disease, an effective strategy to deal with them has yet to be devised. Various new guidewires have been designed in an attempt to negotiate chronic occlusions successfully. The authors have analysed the impact of the Athlete guidewire on procedural success in this lesion subset. METHODS: Sixty-two consecutive patients undergoing percutaneous intervention for chronic total occlusions over a two-year period were retrospectively studied. For the initial attempt, conventional guidewires were used. In case of failure, further attempts were made using the Athlete guidewire. Procedural success rates with the use of conventional and Athlete guidewires were assessed. RESULTS: Failure of the first attempt with the conventional guidewire occurred in 32 (51.6%) patients and success was achieved in 30 (48.4%) patients. In the former patients, a second attempt was made using the Athlete guidewire to cross the occlusion. The second attempt was successful in 20 patients (60%) in whom the first attempt was unsuccessful, while in the remaining 12 (40%) patients the occlusion could not be crossed even during the second attempt and the procedure was then terminated. Following the use of the Athlete guidewire, the success rate increased to 62% (p < 0.001). No complication occurred during the first attempt, while one patient had a coronary perforation using the Athlete guidewire, which was managed successfully without the need for bypass surgery. CONCLUSION: The use of the Athlete guidewire is feasible and safe, and enhances the chances of successfully treating chronic total occlusions during percutaneous coronary revascularization procedures. 相似文献
985.
Rutsch W Kiemeneij F Colombo A Macaya C Guermonprez JL Grip L Hamburger J Umans V Gotsman M Almagor Y Morice MC Garcia E Chevalier B Erbel R Cobaugh M Morel MA Serruys PW 《International journal of cardiovascular interventions》2000,3(3):143-151
BACKGROUND: Although safety and efficacy of the NIR trade mark stent have been reported, the long-term angiographic and clinical outcomes have yet to be investigated. The FINESS-II study (First International NIR Endovascular Stent Study) was designed to assess the procedural safety of single 9 and 16 mm NIR stent implantation, the six-month restenosis rate and finally the six- and 12-month clinical outcome of patients treated with this novel coronary stent. METHODS: Patients with angina and a single de novo lesion in a native coronary artery of >3 and <5 mm diameter were included in this multicentre, prospective, observational trial. Clinical follow-up was obtained at one, six and 12 months. Angiography was performed before and after the stent implantation and at six months. The primary endpoint included major adverse cardiac events (death, myocardial infarction and target lesion revascularization) within 30 days after the procedure. Major bleeding complications and subacute stent thrombosis within the first 30 days were also reported as specific endpoints. Secondary endpoints were major cardiac-event-free survival at six- and 12-month follow-up and angiographic restenosis at six months. RESULTS: A total of 156 patients (81% male, mean age 60 +/- 10 years), with stable (54%), unstable (40%) angina pectoris or silent ischemia (6%) were enrolled. The target vessel diameter was 2.94 +/- 0.54 mm. The minimal lumen diameter pre, post and at follow-up was 1.04 +/- 0.32 mm, 2.64 +/- 0.42 mm and 1.88 +/- 0.63 mm, respectively. Restenosis rate according to the >50% diameter stenosis criterion at six month follow-up was 19% (26/136). At 12 months, the event-free survival rate was 83% (two deaths, one Q-wave and three non-Q-wave myocardial infarctions, four bypass surgery and 17 target lesion revascularizations), while 87% of the patients were free of angina pectoris. CONCLUSION: the outcome of the FINESS-II trial is comparable to those observed in previous stent trials (Benestent II), indicating that the coronary NIR stent is safe and effective as a primary device for the treatment of native coronary artery lesions in patients with (un)stable angina pectoris. 相似文献
986.
Colombo R 《Genomics》2000,69(1):131-134
Cystinuria is an autosomal recessive disorder of the transepithelial transport of amino acids, clinically manifested by the development of kidney stones. Mutations in the gene encoding rBAT (SLC3A1, on chromosome 2p16.3) are linked to type I cystinuria, while the SLC7A9 locus (19q13.1), expressing b0,+ AT protein, is involved in non-type I cystinuria, which is very common among Libyan Jews. Applying two methods for linkage disequilibrium analysis to haplotype data spanning six 19q12-q13.1 polymorphic markers, and relying on the physical distances between the markers and the recently mapped SLC7A9 (CSNU3) locus, the age of the founder missense V170M mutation causing non-type I cystinuria in Jews of Libyan ancestry is calculated to be approximately 14 to 15 generations (g) (95% confidence interval: 9-20 g) or slightly more. The estimated age dates the most recent common ancestor of the mutation-bearing chromosomes back to the time (or some decades before) Jewish families settled in Libya following their expulsion from the Iberian Peninsula. This finding makes the molecular population genetics of cystinuria understandable in the context of the Libyan Jews' history. 相似文献
987.
Michele Potrich Rita T.L. da Silva Fabiana M.C. Maia Everton R. Lozano Robson M. Rossi Fernanda C. Colombo Flavia G. Tedesco Alfredo de Gouvea 《Revista Brasileira de Entomologia》2018,62(1):23-28
This study aimed to evaluate the effect of commercially used entomopathogens on Africanized Apis mellifera L. (Hymenoptera: Apidae). Four bioassays were performed: 1) pulverized entomopathogens on A. mellifera; 2) entomopathogens sprayed on a smooth surface; 3) entomopathogens sprayed on soy leaves; and 4) entomopathogens mixed with candy paste (sugar syrup). Five treatments were prepared: sterile distilled water (control), distilled water sterilized with Tween® 80 (0.01%), and the commercial entomopathogens Metarhizium anisopliae E9 (1.0 × 109 conidia mL?1), Beauveria bassiana PL63 (1.0 × 108 conidia mL?1) and Bacillus thuringiensis var. kurstaki HD-1 (3.0 × 108 spores mL?1). Each treatment consisted of five repetitions, with 20 workers per repetition, which were stored in a plastic box and, later, in a biological oxygen demand (B.O.D.) incubator (27 ± 2 °C, RH of 60% ± 10%, 12-h photophase). The mortality of the workers was evaluated from 1 h to 240 h, and the data were analyzed using Bayesian inference. The workers killed by the ingestion of candy paste contaminated with the pathogens (products) were randomly separated and selected for the removal of the midgut. Each midgut was fixed in Bouin's solution and prepared for histology. B. bassiana was verified to reduce the survival of A. mellifera workers in all bioassays. Moreover, M. anisopliae reduced the survival of A. mellifera workers directly sprayed, on a smooth surface and mixed with candy. B. thuringiensis reduced A. mellifera survival on a smooth surface and mixed with candy paste. However, its effects were lower than that observed by B. bassiana. The treatments with the biological products did not induce morphometric alterations in the midgut of A. mellifera. 相似文献
988.
Elisabetta Galbiati Svetlana Avvakumova Alessandra La Rocca Maria Pozzi Silvia Messali Paola Magnaghi Miriam Colombo Davide Prosperi Paolo Tortora 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(10):2254-2260
Background
Vaults are eukaryotic ribonucleoprotein particles composed of up 78 copies of the 97?kDa major vault protein that assembles into a barrel-like, “nanocapsule” enclosing poly(ADP-ribose) polymerase, telomerase-associated protein-1 and small untranslated RNAs. Overall, the molecular mass of vault particles amounts to about 13?MDa. Although it has been implicated in several cellular functions, its physiological roles remain poorly understood. Also, the possibility to exploit it as a nanovector for drug delivery is currently being explored in several laboratories.Methods
Using the baculovirus expression system, vaults were expressed and purified by a dialysis step using a 1?MDa molecular weight cutoff membrane and a subsequent size exclusion chromatography. Purity was assessed by SDS-PAGE, transmission electron microscopy and dynamic light scattering. Particle's endocytic uptake was monitored by flow cytometry and confocal microscopy.Results
The purification protocol here reported is far simpler and faster than those currently available and lead to the production of authentic vault. We then demonstrated its clathrin-mediated endocytic uptake by normal fibroblast and glioblastoma, but not carcinoma cell lines. In contrast, no significant caveolin-mediated endocytosis was detected.Conclusions
These results provide the first evidence for an intrinsic propensity of the vault complex to undergo endocytic uptake cultured eukaryotic cells.General significance
The newly developed purification procedure will greatly facilitate any investigation based on the use of the vault particle as a natural nanocarrier. Its clathrin-mediated endocytic uptake observed in normal and in some tumor cell lines sheds light on its physiological role. 相似文献989.
Michele Vitali Valentina Rigamonti Antonino Natalello Barbara Colzani Svetlana Avvakumova Stefania Brocca Carlo Santambrogio Joanna Narkiewicz Giuseppe Legname Miriam Colombo Davide Prosperi Rita Grandori 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(7):1556-1564
Background
Protein-nanoparticle (NP) interactions dictate properties of nanoconjugates relevant to bionanotechnology. Non-covalent adsorption generates a protein corona (PC) formed by an inner and an outer layer, the hard and soft corona (HC, SC). Intrinsically disordered proteins (IDPs) exist in solution as conformational ensembles, whose response to the presence of NPs is not known.Methods
Three IDPs (α-casein, Sic1 and α-synuclein) and lysozyme are compared, describing conformational properties inside HC on silica NPs by circular dichroism (CD) and Fourier-transform infrared (FTIR) spectroscopy.Results
IDPs inside HC are largely unstructured, but display small, protein-specific conformational changes. A minor increase in helical content is observed for α-casein and α-synuclein, reminiscent of membrane effects on α-synuclein. Frozen in their largely disordered conformation, bound proteins do not undergo folding induced by dehydration, as they do in their free forms. While HC thickness approaches the hydrodynamic diameter of the protein in solution for lysozyme, it is much below the respective values for IDPs. NPs boost α-synuclein aggregation kinetics in a dose-dependent manner.Conclusions
IDPs maintain structural disorder inside HC, experiencing minor, protein-specific, induced folding and stabilization against further conformational transitions, such as formation of intermolecular beta-sheets upon dehydration. The HC is formed by a single layer of protein molecules. SC likely plays a key role stabilizing amyloidogenic α-synuclein conformers.General significance
Protein-NP interactions can mimic those with macromolecular partners, allowing dissection of contributing factors by rational design of NP surfaces. Application of NPs in vivo should be carefully tested for amyloidogenic potential. 相似文献990.
Vito Terlizzi Marco Lucarelli Donatello Salvatore Adriano Angioni Arianna Bisogno Cesare Braggion Roberto Buzzetti Vincenzo Carnovale Rosaria Casciaro Giuseppe Castaldo Natalia Cirilli Mirella Collura Carla Colombo Antonella Miriam Di Lullo Ausilia Elce Vincenzina Lucidi Elisa Madarena Rita Padoan Serena Quattrucci Valeria Raia Manuela Seia Lisa Termini Federica Zarrilli 《BMC pulmonary medicine》2018,18(1):196