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61.
62.
Studies on purine enzymes in experimental colitis 总被引:4,自引:0,他引:4
Although the role of adenosine deaminase (ADA), adenylate deaminase (AMP-DA), purine nucleoside phosphorylase (PNP) is well documented in gastric and intestinal carcinoma, their role in inflammatory bowel diseases remains unknown. In the present study, we investigated the profile of these enzymes in blood and intestinal tissues during colitis. Colitis induced in Wistar rats by acetic acid was monitored by a marker enzyme myeloperoxidase (MPO). The tissue levels of MPO increased on 1, 2, 5 and 6 days post-administration (PA) of acetic acid and declined to the control levels by day 7 PA. In parallel the blood levels of ADA and AMP-DA decreased on days 1, 2 and 5 without any significant change on days 6 and 7 PA. Similar observations were recorded for these enzymes in the cytosolic extracts of colonic tissue specimens. In contrast, PNP remained unaltered in both blood and tissue samples. These findings suggest an inverse-relationship between inflammation and purine deaminases in both blood and tissues. 相似文献
63.
Diffusion Tensor Magnetic Resonance Imaging of Trigeminal Nerves in Relapsing Herpetic Keratouveitis
Antoine Rousseau Gha?daa Nasser Christophe Chiquet Emmanuel Barreau Gael Gendron Godefroy Kaswin Mohamed M’Garrech Farida Benoudiba Denis Ducreux Marc Labetoulle 《PloS one》2015,10(4)
Background
Corneal hypoesthesia is the landmark of HSV and VZV keratitis and can lead to neurotrophic keratitis. Diffusion tensor imaging (DTI) is a new magnetic resonance imaging (MRI) derived technique, which offers possibilities to study axonal architecture. We aimed at assessing the potential impact of recurrent HSV or VZV-related keratitis on the axonal architecture of trigeminal nerves using DTI.Design
Prospective non-interventional study.Participants
Twelve patients and 24 controls.Methods
DTI using MRI of the trigeminal fibers and corneal esthesiometry using the Cochet-Bonnet esthesiometer were acquired for patients affected by unilateral and recurrent HSV or VZV-related keratitis (3 months after the last corneal inflammatory event), and control subjects with no history of ocular or neuronal disease affecting the trigeminal pathways.Main Outcome Measures
Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were compared between the 2 eyes of both patients and controls, and correlated with corneal esthesiometry.Results
FA was lower in the trigeminal fibers ipsilateral to the affected eye compared to the non-affected side (0.39±0.02 versus 0.46±0.04, P=0.03). This difference was more important than the intra-individual variability observed in controls. Concomitantly, the asymmetry in ADC results was significantly correlated with the loss of corneal sensitivity in the affected eye.Conclusions
Corneal hypoesthesia related to HSV and VZV keratitis is associated with persistent modifications in the architecture and functionality of the trigeminal fibers. These results add further explanation to the pathogenesis of HSV and VZV-induced neurotrophic keratitis, which may occur despite an apparent quiescence of the disease. 相似文献64.
65.
Adouda Salmi Farida Boulila Yasmina Bourebaba Christine Le Roux Djellali Belhadi Philippe de Lajudie 《Systematic and applied microbiology》2018,41(5):452-459
Fifty-two slow-growing strains were isolated from root nodules of Calicotome spinosa grown in the Northeast of Algeria and grouped in 24 rep-PCR clusters. One representative strain for each profile was further phylogenetically characterized. The nearly complete 16S rRNA gene sequence indicated that all strains were affiliated to Bradyrhizobium. Multi-Locus Sequence Analysis (MLSA) of the atpD, glnII and recA genes and of the 16S-23S rRNA internal transcribed spacer (ITS) showed that these strains formed four divergent clusters: one close to Bradyrhizobium canariense and Bradyrhizobium lupini and three others separate from all the described species, representing three putative new Bradyrhizobium species. A phylogenetic analysis based on the nodC gene sequence affiliated the strains to either of the two symbiovars, genistearum or retamae. 相似文献
66.
Lawrence G. Welch Sew-Yeu Peak-Chew Farida Begum Tim J. Stevens Sean Munro 《The Journal of cell biology》2021,220(10)
The fidelity of Golgi glycosylation is, in part, ensured by compartmentalization of enzymes within the stack. The COPI adaptor GOLPH3 has been shown to interact with the cytoplasmic tails of a subset of Golgi enzymes and direct their retention. However, other mechanisms of retention, and other roles for GOLPH3, have been proposed, and a comprehensive characterization of the clientele of GOLPH3 and its paralogue GOLPH3L is lacking. GOLPH3’s role is of particular interest as it is frequently amplified in several solid tumor types. Here, we apply two orthogonal proteomic methods to identify GOLPH3+3L clients and find that they act in diverse glycosylation pathways or have other roles in the Golgi. Binding studies, bioinformatics, and a Golgi retention assay show that GOLPH3+3L bind the cytoplasmic tails of their clients through membrane-proximal positively charged residues. Furthermore, deletion of GOLPH3+3L causes multiple defects in glycosylation. Thus, GOLPH3+3L are major COPI adaptors that impinge on most, if not all, of the glycosylation pathways of the Golgi. 相似文献
67.
Papaleo E Ranzani V Tripodi F Vitriolo A Cirulli C Fantucci P Alberghina L Vanoni M De Gioia L Coccetti P 《PLoS computational biology》2011,7(5):e1002056
E2 ubiquitin-conjugating enzymes are crucial mediators of protein ubiquitination, which strongly influence the ultimate fate of the target substrates. Recently, it has been shown that the activity of several enzymes of the ubiquitination pathway is finely tuned by phosphorylation, an ubiquitous mechanism for cellular regulation, which modulates protein conformation. In this contribution, we provide the first rationale, at the molecular level, of the regulatory mechanism mediated by casein kinase 2 (CK2) phosphorylation of E2 Cdc34-like enzymes. In particular, we identify two co-evolving signature elements in one of the larger families of E2 enzymes: an acidic insertion in β4α2 loop in the proximity of the catalytic cysteine and two conserved key serine residues within the catalytic domain, which are phosphorylated by CK2. Our investigations, using yeast Cdc34 as a model, through 2.5 μs molecular dynamics simulations and biochemical assays, define these two elements as an important phosphorylation-controlled switch that modulates opening and closing of the catalytic cleft. The mechanism relies on electrostatic repulsions between a conserved serine phosphorylated by CK2 and the acidic residues of the β4α2 loop, promoting E2 ubiquitin charging activity. Our investigation identifies a new and unexpected pivotal role for the acidic loop, providing the first evidence that this loop is crucial not only for downstream events related to ubiquitin chain assembly, but is also mandatory for the modulation of an upstream crucial step of the ubiquitin pathway: the ubiquitin charging in the E2 catalytic cleft. 相似文献
68.
Masahiro Yao Farida Latif Mary Lou Orcutt Igor Kuzmin Thomas Stackhouse Fang wei Zhou Kalman Tory Fuh mei Duh Frances Richards Eamonn Maher Sal LaForgia Kay Huebner Denis Le Pasilier Marston Linehan Michael Lerman Berton Zbar 《Human genetics》1993,92(6):605-614
Von Hippel-Lindau disease (VHL) is an inherited multisystem neoplastic disorder. We prepared a 2.5-megabase (Mb) restriction map of the region surrounding the VHL gene and identified and characterized overlapping deletions in three unrelated patients affected with VHL. The smallest nested deletion (100 kb) was located within a 510-kb NruI fragment detected by 19–63. The rearrangements detected will be useful in isolating and evaluating candidate cDNAs for the VHL gene. The detailed physical map will be useful in studying the organization and structure of genes in the VHL region. 相似文献
69.
Saha SK Al Emran HM Hossain B Darmstadt GL Saha S Islam M Chowdhury AI Foster D Naheed A El Arifeen S Baqui AH Qazi SA Luby SP Breiman RF Santosham M Black RE Crook DW;Pneumococcal Study Group 《PloS one》2012,7(3):e32134
Background
Streptococcus pneumoniae is a leading cause of meningitis in countries where pneumococcal conjugate vaccines (PCV) targeting commonly occurring serotypes are not routinely used. However, effectiveness of PCV would be jeopardized by emergence of invasive pneumococcal diseases (IPD) caused by serotypes which are not included in PCV. Systematic hospital based surveillance in Bangladesh was established and progressively improved to determine the pathogens causing childhood sepsis and meningitis. This also provided the foundation for determining the spectrum of serotypes causing IPD. This article reports an unprecedented upsurge of serotype 2, an uncommon pneumococcal serotype, without any known intervention.Methods and Findings
Cases with suspected IPD had blood or cerebrospinal fluid (CSF) collected from the beginning of 2001 till 2009. Pneumococcal serotypes were determined by capsular swelling of isolates or PCR of culture-negative CSF specimens. Multicenter national surveillance, expanded from 2004, identified 45,437 patients with suspected bacteremia who were blood cultured and 10,618 suspected meningitis cases who had a lumber puncture. Pneumococcus accounted for 230 culture positive cases of meningitis in children <5 years. Serotype-2 was the leading cause of pneumococcal meningitis, accounting for 20.4% (45/221; 95% CI 15%–26%) of cases. Ninety eight percent (45/46) of these serotype-2 strains were isolated from meningitis cases, yielding the highest serotype-specific odds ratio for meningitis (29.6; 95% CI 3.4–256.3). The serotype-2 strains had three closely related pulsed field gel electrophoresis types.Conclusions
S. pneumoniae serotype-2 was found to possess an unusually high potential for causing meningitis and was the leading serotype-specific cause of childhood meningitis in Bangladesh over the past decade. Persisting disease occurrence or progressive spread would represent a major potential infection threat since serotype-2 is not included in PCVs currently licensed or under development. 相似文献70.
Glenn Gladys M. Daniel Lambert N. Choyke Peter Linehan W. Marston Oldfield Edward Gorin Michael B. Hosoe Shigeto Latif Farida Weiss Gary Walther McClellan Lerman Michael I. Zbar Berton 《Human genetics》1991,87(2):207-210
Summary As part of an attempt to locate the von Hippel-Lindau locus (VHL) on chromosome 3, we evaluated 41 families with von Hippel-Lindau disease from the United States and Canada. One large family was identified whose disease phenotype was distinct from typical VHL. The most common disease manifestation was pheochromocytoma occuring in 57% (27/47) of affected family members. Few (4/47) affected family members had symptomatic spinal or cerebellar hemangioblastomas; no affected family member had renal cell carcinoma (0/47) or pancreatic cysts (0/24). Previously, genetic analysis demonstrated that the disease manifestations in this family were linked to RAF1 and D3S18, markers shown to be linked to typical VHL. These results suggest that there are mutant alleles at the VHL locus associated with distinct tissue specificities. 相似文献