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81.
Kallijärvi J Lahtinen U Hämäläinen R Lipsanen-Nyman M Palvimo JJ Lehesjoki AE 《Experimental cell research》2005,308(1):146-155
Mulibrey nanism is an autosomal recessive prenatal-onset growth disorder characterized by dysmorphic features, cardiomyopathy, and hepatomegaly. Mutations in TRIM37 encoding a tripartite motif (TRIM, RING-B-box-coiled-coil)-family protein underlie mulibrey nanism. We investigated the ubiquitin ligase activity predicted for the RING domain of TRIM37 by analyzing its autoubiquitination. Full-length TRIM37 and its TRIM domain were highly polyubiquitinated when co-expressed with ubiquitin. Polyubiquitination was decreased in a mutant protein with disrupted RING domain (Cys35Ser;Cys36Ser) and in the Leu76Pro mutant protein, a disease-associated missense mutation affecting the TRIM domain of TRIM37. Bacterially produced GST-TRIM domain fusion protein, but not its Cys35Ser;Cys36Ser or Leu76Pro mutants, were polyubiquitinated in cell-free conditions, implying RING-dependent modification. Ubiquitin was also identified as an interaction partner for TRIM37 in a yeast two-hybrid screen. Ectopically expressed TRIM37 rapidly formed aggregates that were ubiquitin-, proteasome subunit-, and chaperone-positive in immunofluorescence analysis, defining them as aggresomes. The Cys35Ser;Cys36Ser mutant and the Leu76Pro and Gly322Val patient mutant proteins were markedly less prone to aggregation, implying that aggresomal targeting reflects a physiological function of TRIM37. These findings suggest that TRIM37 acts as a TRIM domain-dependent E3 ubiquitin ligase and imply defective ubiquitin-dependent degradation of an as-yet-unidentified target protein in the pathogenesis of mulibrey nanism. 相似文献
82.
Stéphanie Bostr?m Samad Ibitokou Mayke Oesterholt Christentze Schmiegelow Jan-Olov Persson Daniel Minja John Lusingu Martha Lemnge Nadine Fievet Philippe Deloron Adrian J. F. Luty Marita Troye-Blomberg 《PloS one》2012,7(11)
In pregnant women, Plasmodium falciparum infections are an important cause of maternal morbidity as well as fetal and neonatal mortality. Erythrocytes infected by these malaria-causing parasites accumulate through adhesive interactions in placental intervillous spaces, thus evading detection in peripheral blood smears. Sequestered infected erythrocytes induce inflammation, offering the possibility of detecting inflammatory mediators in peripheral blood that could act as biomarkers of placental infection. In a longitudinal, prospective study in Tanzania, we quantified a range of different cytokines, chemokines and angiogenic factors in peripheral plasma samples, taken on multiple sequential occasions during pregnancy up to and including delivery, from P. falciparum-infected women and matched uninfected controls. The results show that during healthy, uninfected pregnancies the levels of most of the panel of molecules we measured were largely unchanged except at delivery. In women with P. falciparum, however, both comparative and longitudinal assessments consistently showed that the levels of IL-10 and IP-10 increased significantly whilst that of RANTES decreased significantly, regardless of gestational age at the time the infection was detected. ROC curve analysis indicated that a combination of increased IL-10 and IP-10 levels and decreased RANTES levels might be predictive of P. falciparum infections. In conclusion, our data suggest that host biomarkers in peripheral blood may represent useful diagnostic markers of P. falciparum infection during pregnancy, but placental histology results would need to be included to verify these findings. 相似文献
83.
Sharmila Vaz Marita Falkmer Marina Ciccarelli Anne Passmore Richard Parsons Tele Tan Torbjorn Falkmer 《PloS one》2015,10(4)
School belongingness has gained currency among educators and school health professionals as an important determinant of adolescent health. The current cross-sectional study presents the 15 most significant personal and contextual factors that collectively explain 66.4% (two-thirds) of the variability in 12-year old students’ perceptions of belongingness in primary school. The study is part of a larger longitudinal study investigating the factors associated with student adjustment in the transition from primary to secondary school. The study found that girls and students with disabilities had higher school belongingness scores than boys, and their typically developing counterparts respectively; and explained 2.5% of the variability in school belongingness. The majority (47.1% out of 66.4%) of the variability in school belongingness was explained by student personal factors, such as social acceptance, physical appearance competence, coping skills, and social affiliation motivation; followed by parental expectations (3% out of 66.4%), and school-based factors (13.9% out of 66.4%) such as, classroom involvement, task-goal structure, autonomy provision, cultural pluralism, and absence of bullying. Each of the identified contributors of primary school belongingness can be shaped through interventions, system changes, or policy reforms. 相似文献
84.
Background
Despite an ambition from adults with Autism Spectrum Disorder (ASD) to be employed, there are limited opportunities for competitive employment for this group. Employment is not only an entitlement enjoyed by others in society, but employing adults with ASD also has economic benefits by decreasing lost productivity and resource costs for this group. Few studies have explored the cost-benefit ratio for employing adults with ASD and even fewer have taken the viewpoint of the employer, particularly applying this situation to ASD. Until such study occurs, employers may continue to be reluctant to employ adults from this group.Objective
This review aimed to examine the costs, benefits and the cost-benefit ratio of employing adults with ASD, from a societal perspective and from the perspective of employers.Methods
Eight databases were searched for scientific studies within defined inclusion criteria. These databases included CINAHL Plus, Cochrane Library, Emerald, Ovid Medline, ProQuest, PsycINFO, Scopus and Web of Science.Results and Conclusion
Enhancing the opportunities for adults with ASD to join the workforce is beneficial from a societal perspective, not only from an inclusiveness viewpoint, but also from a strict economic standpoint. Providing supported employment services for adults with ASD does not only cut the cost compared with providing standard care, it also results in better outcomes for adults with ASD. Despite the fact that ASD was the most expensive group to provide vocational rehabilitation services for, adults with ASD have a strong chance of becoming employed once appropriate measures are in place. Hence, rehabilitation services could be considered as a worthwhile investment. The current systematic review uncovered the fact that very few studies have examined the benefits, the costs and the cost-benefit ratio of employing an adult with ASD from the perspective of employers indicating a need for this topic to be further explored. 相似文献85.
Rami Kantor Daniel Bettendorf Ronald J. Bosch Marita Mann David Katzenstein Susan Cu-Uvin Richard D’Aquila Lisa Frenkel Susan Fiscus Robert Coombs for the ACTG A Study Team 《PloS one》2014,9(4)
Background
Detectable HIV-1 in body compartments can lead to transmission and antiretroviral resistance. Although sex differences in viral shedding have been demonstrated, mechanisms and magnitude are unclear. We compared RNA levels in blood, genital-secretions and saliva; and drug resistance in plasma and genital-secretions of men and women starting/changing antiretroviral therapy (ART) in the AIDS Clinical Trials Group (ACTG) 5077 study.Methods
Blood, saliva and genital-secretions (compartment fluids) were collected from HIV-infected adults (≥13 years) at 14 United-States sites, who were initiating or changing ART with plasma viral load (VL) ≥2,000 copies/mL. VL testing was performed on all compartment fluids and HIV resistance genotyping on plasma and genital-secretions. Spearman rank correlations were used to evaluate concordance and Fisher’s and McNemar’s exact tests to compare VL between sexes and among compartments.Results
Samples were available for 143 subjects; 36% treated (23 men, 29 women) and 64% ‘untreated’ (40 men, 51 women). RNA detection was significantly more frequent in plasma (100%) than genital-secretions (57%) and saliva (64%) (P<0.001). A higher proportion of men had genital shedding versus women (78% versus 41%), and RNA detection was more frequent in saliva versus genital-secretions in women when adjusted for censoring at the limit of assay detection. Inter-compartment fluid VL concordance was low in both sexes. In 22 (13 men, 9 women) paired plasma-genital-secretion genotypes from treated subjects, most had detectable resistance in both plasma (77%) and genital-secretions (68%). Resistance discordance was observed between compartments in 14% of subjects.Conclusions
HIV shedding and drug resistance detection prior to initiation/change of ART in ACTG 5077 subjects differed among tissues and between sexes, making the gold standard blood-plasma compartment assessment not fully representative of HIV at other tissue sites. Mechanisms of potential sex-dependent tissue compartmentalization should be further characterized to aid in optimizing treatment and prevention of HIV transmission.Trial Registration
ClinicalTrials.gov NCT00007488相似文献86.
87.
Jelena Mrdalj St?le Pallesen Anne Marita Milde Finn Konow Jellestad Robert Murison Reidun Ursin Bj?rn Bjorvatn Janne Gr?nli 《PloS one》2013,8(7)
Exposure to early life stress may profoundly influence the developing brain in lasting ways. Neuropsychiatric disorders associated with early life adversity may involve neural changes reflected in EEG power as a measure of brain activity and disturbed sleep. The main aim of the present study was for the first time to characterize possible changes in adult EEG power after postnatal maternal separation in rats. Furthermore, in the same animals, we investigated how EEG power and sleep architecture were affected after exposure to a chronic mild stress protocol. During postnatal day 2–14 male rats were exposed to either long maternal separation (180 min) or brief maternal separation (10 min). Long maternally separated offspring showed a sleep-wake nonspecific reduction in adult EEG power at the frontal EEG derivation compared to the brief maternally separated group. The quality of slow wave sleep differed as the long maternally separated group showed lower delta power in the frontal-frontal EEG and a slower reduction of the sleep pressure. Exposure to chronic mild stress led to a lower EEG power in both groups. Chronic exposure to mild stressors affected sleep differently in the two groups of maternal separation. Long maternally separated offspring showed more total sleep time, more episodes of rapid eye movement sleep and higher percentage of non-rapid eye movement episodes ending in rapid eye movement sleep compared to brief maternal separation. Chronic stress affected similarly other sleep parameters and flattened the sleep homeostasis curves in all offspring. The results confirm that early environmental conditions modulate the brain functioning in a long-lasting way. 相似文献
88.
Mosconi M Giesen U Langner F Mielke C Dalla Rosa I Dirks WG 《Radiation and environmental biophysics》2011,50(3):345-352
An improved assessment of the biological effects and related risks of low doses of ionizing radiation is currently an important
issue in radiation biology. Irradiations using microbeams are particularly well suited for precise and localized dose depositions,
whereas recombinant cell lines with fluorescent proteins allow the live observation of radiation-induced foci. Living cells
of the fibrosarcoma cell line HT-1080 stably expressing 53BP1 or full-length reconstituted MDC1 fused to Green Fluorescent
Protein (GFP) were irradiated with protons and α-particles of linear energy transfers (LETs) of 15 and 75 keV/μm, respectively.
Using a microbeam, the irradiations were carried out in line patterns, which facilitated the discrimination between undefined
background and radiation-induced foci. As expected, foci formation and respective kinetics from α-particle irradiations with
a high LET of 75 keV/μm could be detected in a reliable manner by both fusion proteins, as reported previously. Colocalization
of γ-H2AX foci confirmed the DSB nature of the detected foci. As a novel result, the application of protons with low LET of
15 keV/μm generated 53BP1- and MDC1-mediated foci of almost equal size and slightly different kinetics. This new data expands
the capability of 53BP1 and wild-type MDC1 on visible foci formation in living cells after irradiation with low-LET particles.
Furthermore, the kinetics in HT-1080 cells for α-particle irradiation show a delay of about 20 s for 53BP1 foci detection
compared to wild-type MDC1, confirming the hierarchical assembly of both proteins. Preliminary data for proton irradiations
are shown and also these indicate a delay for 53BP1 versus MDC1. 相似文献
89.
Sajjad A Holley MP Labbate M Stokes HW Gillings MR 《Applied and environmental microbiology》2011,77(1):335-337
The presence of integrons was assessed in gut bacteria isolated from wild-caught prawns. A pseudomonad was recovered that contained a Tn402-like class 1 integron with a complete transposition module and two gene cassettes. One cassette was identical to a previously described cassette from a chromosomal class 3 integron in Delftia tsuruhatensis. 相似文献
90.