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931.
Priscilla Sassoli de Bianchi Cinzia Campari Silvia Mancini Orietta Giuliani Patrizia Landi Luisa Paterlini Carlo Naldoni Alba C. Finarelli Fabio Falcini Maurizio Ponz de Leon Romano Sassatelli Elisabetta Borciani Fabio Fornari Giorgio Gatti Marella Zatelli Corrado Zurlini Federica Rossi Rossella Corradini Lauro Bucchi 《Cancer epidemiology》2013,37(4):469-473
Background: In some Italian areas, colonoscopic surveillance of first-degree relatives (FDRs) of colorectal cancer (CRC) patients is provided as a part of local population-based faecal occult blood test (FOBT) screening programmes. The objective of the present study was to assess the feasibility and early results of this surveillance model. Methods: Data from district screening centres were used to evaluate the process of identification and selection of eligible FDRs (residence in the Emilia-Romagna Region, age 40–75 years, no recent colonoscopy) of screen-detected CRC patients and the detected prevalence of disease. The probability for an FDR to undergo colonoscopy and to be diagnosed with CRC and advanced adenoma was estimated using the Kaplan–Meier method. The sex- and age-standardised ratio of detected prevalence to that expected based on results from a colonoscopy screening study of the Italian general population was estimated. Results: Between 2005 and 2011, 9319 FDRs of 2437 screen-detected CRC patients (3.8 per patient) were identified and contacted. Their likelihood of being eligible for, and accepting, colonoscopy was 0.11 (95% confidence interval: 0.11–0.12). Among the 926 subjects undergoing colonoscopy, the prevalence of previous negative screening FOBT was 63%. Eleven CRCs (1.2%) and 100 advanced adenomas (10.8%) were detected. The standardised ratio of detected prevalence to that expected was 0.91 (95% confidence interval: 0.19–2.66) for CRC and 1.48 (1.04–2.05) for advanced adenoma. Conclusions: The procedure of selection of FDRs was extremely ineffective. Due to previous negative screening tests, the prevalence of disease was less than expected. A population-based FOBT screening programme is a highly unsuitable setting for the provision of surveillance to FDRs of CRC patients. 相似文献
932.
Benedetta Fongaro Elia Cappelletto Alice Sosic Barbara Spolaore Patrizia de Polverino de Laureto 《Protein science : a publication of the Protein Society》2022,31(7)
Parkinson''s disease (PD) is a chronic multifactorial disease, whose etiology is not completely understood. The amyloid aggregation of α‐synuclein (Syn) is considered a major cause in the development of the disease. The presence of genetic mutations can boost the aggregation of the protein and the likelihood to develop PD. These mutations can lead to early onset (A30P, E46K, and A53T) or late‐onset (H50Q) forms of PD. The disease is also linked to an increase in oxidative stress and altered levels of dopamine metabolites. The molecular interaction of these molecules with Syn has been previously studied, while their effect on the pathological mutant structure and function is not completely clarified. By using biochemical and biophysical approaches, here we have studied the interaction of the familial variant E46K with two dopamine‐derived catechols, 3,4‐dihydroxyphenylacetic acid and 3,4‐dihydroxyphenylethanol. We show that the presence of these catechols causes a decrease in the formation of amyloid fibrils in a dose‐dependent manner. Native‐ and Hydrogen/deuterium exchange‐mass spectrometry (HDX‐MS) provide evidence that this effect is strongly conformation dependent. Indeed, these molecules interact differently with the interconverting conformers of Syn and its familial variant E46K in solution, selecting the most prone‐to‐aggregation one, confining it into an off‐pathway oligomer. These findings suggest that catechols could be a molecular scaffold for the design of compounds potentially useful in the treatment of Parkinson''s disease and related conditions. 相似文献
933.
934.
Gabriella Siesto Angela Capece Matthias Sipiczki Hajnalka Csoma Patrizia Romano 《Annals of microbiology》2013,63(2):661-668
In this study, wild Saccharomyces cerevisiae strains, isolated from spontaneously fermenting grapes of different varieties and origins, were submitted to genetic analysis using different molecular techniques, such as amplification of genes coding for cell wall proteins and containing minisatellite-like sequences, karyotyping, mtDNA-RFLP, and analysis of the δ region. The lowest discriminative power was obtained by minisatellites analysis, in particular the amplification of AGA1 genes. Karyotyping and mtDNA-RFLP analysis yielded the same differentiation among the strains, whereas the PCR amplification of δ sequences resulted the best method as it was fast and it showed a very high discriminative power. In any case, it has to be underlined that some strains, showing the same delta profiles, exhibited a different mtDNA restriction profile and electrophoretic karyotype, suggesting that more than one molecular marker is required for reliable strain discrimination. Although the techniques used revealed a different resolution power, they all revealed a genetic relationship among strains isolated from spontaneous fermentation of grapes of different origins. In fact, none of the typing methods was able to discriminate some strains isolated from different areas. 相似文献
935.
Ryan?P. Liegel Mark?T. Handley Adam Ronchetti Stephen Brown Lars Langemeyer Andrea Linford Bo Chang Deborah?J. Morris-Rosendahl Sarah Carpanini Renata Posmyk Verity Harthill Eamonn Sheridan Ghada?M.H. Abdel-Salam Paulien?A. Terhal Francesca Faravelli Patrizia Accorsi Lucio Giordano Lorenzo Pinelli Britta Hartmann Allison?D. Ebert Francis?A. Barr Irene?A. Aligianis Duska?J. Sidjanin 《American journal of human genetics》2013,92(6):1001-1007
Infantile myofibromatosis (IM) is a disorder of mesenchymal proliferation characterized by the development of nonmetastasizing tumors in the skin, muscle, bone, and viscera. Occurrence within families across multiple generations is suggestive of an autosomal-dominant (AD) inheritance pattern, but autosomal-recessive (AR) modes of inheritance have also been proposed. We performed whole-exome sequencing (WES) in members of nine unrelated families clinically diagnosed with AD IM to identify the genetic origin of the disorder. In eight of the families, we identified one of two disease-causing mutations, c.1978C>A (p.Pro660Thr) and c.1681C>T (p.Arg561Cys), in PDGFRB. Intriguingly, one family did not have either of these PDGFRB mutations but all affected individuals had a c.4556T>C (p.Leu1519Pro) mutation in NOTCH3. Our studies suggest that mutations in PDGFRB are a cause of IM and highlight NOTCH3 as a candidate gene. Further studies of the crosstalk between PDGFRB and NOTCH pathways may offer new opportunities to identify mutations in other genes that result in IM and is a necessary first step toward understanding the mechanisms of both tumor growth and regression and its targeted treatment. 相似文献
936.
Fabrizio Aragozzini Mario Valenti Enzo Santaniello Patrizia Ferraboschi Paride Grisenti 《Biocatalysis and Biotransformation》1992,5(4):325-332
The synthesis of optically active ethyl 4-chloro-3-X-butanoate derivatives la-d (X = OH, a; OCOCH3, b; OCOC3H7, c; OCH2C6H5, d) was realized using various biocatalytic approaches such as microbiological reduction of ethyl 4-chloro-3-oxobutanoate 2 with lactic acid bacteria, hydrolysis of lb-d by the hydrolytic enzymes PLE and BChE and the transesterification of la catalyzed by a lipase from Pseudomonas fluorescens (PFL). 相似文献
937.
Gian Maria Rossolini Patrizia Muscas Alessandra Chiesurin Giuseppe Satta 《FEMS microbiology letters》1993,114(3):259-265
Abstract The fimA gene coding for the major component (fimbrin) of type 1 fimbriae was mapped within the Salmonella typhi fim gene cluster, and its nucleotide sequence determined. The deduced amino acid sequence of S. typhi fimbrin is highly homologous to that of S. typhimurium type 1 fimbrin and showed similarity to that of other enterobacterial type 1 fimbrins. Downstream of fimA , an open reading frame was found, named fimI , able to encode a fimbrin-like protein. The fimI product could represent the counterpart, in type 1 fimbriae, of the PapH protein involved in cell anchoring and length modulation of Escherichia coli Pap pili. This genetic organization was found to be common to other Salmonella serovars, including S. typhimurium and S. choleraesuis . 相似文献
938.
Maria Cristina Polidori Ketty Savino Gianfranco Alunni Michela Freddio Umberto Senin Helmut Sies Wilhelm Stahl Patrizia Mecocci 《Free radical biology & medicine》2002,32(2):148-152
Plasma levels of malondialdehyde (MDA), vitamin A, and of antioxidant micronutrients including vitamin E, lutein, zeaxanthin, beta-cryptoxanthin, lycopene, and alpha- and beta-carotene were measured in 30 patients with class II and III congestive heart failure (CHF) according to the New York Heart Association (NYHA) classification and in 55 controls. Ejection fraction was evaluated by echocardiography in all patients as a measure of the emptying capacity of the heart. Plasma levels of all measured compounds were significantly lower and MDA significantly higher in patients compared to controls (p <.001). Class II NYHA patients showed significantly lower MDA levels and significantly higher levels of vitamin A, vitamin E, lutein, and lycopene than class III patients. Ejection fraction was inversely correlated with MDA levels and directly correlated with vitamin A, vitamin E, lutein, and lycopene levels in patients. The present study supports the concept that an increased consumption of vitamin-rich fruits and vegetables might help in achieving cardiovascular health. 相似文献
939.
Pucciarelli S La Terza A Ballarini P Barchetta S Yu T Marziale F Passini V Methé B Detrich HW Miceli C 《Marine Genomics》2009,2(1):57-66
Euplotes focardii is a marine ciliated protozoan discovered in the Ross Sea near Terra Nova Bay, Antarctica. This organism is strictly psychrophilic, survives and reproduces optimally at 4–5 °C, and has a genome rich in A/T base pairs. Like other ciliated protozoans, Euplotes spp. are characterized by nuclear dimorphism: 1) the germline micronucleus contains the entire genome as large chromosomes; and 2) the somatic macronucleus ( 50 megabases, or 5% of the micronuclear genome) contains small linear DNA nanochromosomes [1–12 kilobases], each of which constitutes a single genetic unit. These characteristics make E. focardii an ideal model for genome-level analysis to understand the evolutionary mechanisms that determine the adaptation of organisms to cold environments. Here we describe two examples that are controlled by phylogenetically appropriate comparison with mesophilic and psychrotolerant Euplotes species: 1) the genes and encoded proteins of the E. focardii tubulin superfamily, including α-, β-, and γ-tubulins; and 2) the genes of the heat-shock protein (Hsp) 70 family. The tubulins provide particular insight into protein-level structural changes that are likely to facilitate microtubule nucleation and polymerization in an energy poor environment. By contrast, the hsp70 genes of E. focardii and of its psychrotolerant relative E. nobilii reveal adaptive alterations in the regulation of gene expression in the cold. The unique characteristics of the E. focardii genome and the results that we present here argue strongly for a concerted effort to characterize the relatively low complexity macronuclear genome of this psychrophilic organism. 相似文献
940.
Anna Di Benedetto Marcella Mottolese Francesca Sperati Cristiana Ercolani Luigi Di Lauro Laura Pizzuti Patrizia Vici Irene Terrenato Abeer M. Shaaban Matthew P. Humphries Sreekumar Sundara‐Rajan Maddalena Barba Valerie Speirs Ruggero De Maria Marcello Maugeri‐Saccà 《Journal of cellular physiology》2017,232(8):2246-2252