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141.
Renato L. T. Parreira Eveline S. Costa Vladimir C. G. Heleno Lizandra G. Magalhes Julia M. Souza Patrícia M. Pauletti Wilson R. Cunha Ana H. Janurio Guilherme V. Símaro Jairo K. Bastos Rosangela S. Laurentiz Tapas Kar Giovanni F. Caramori Daniel Fbio Kawano Mrcio L. AndradeeSilva 《化学与生物多样性》2019,16(1)
Six dibenzylbutyrolactonic lignans ((?)‐hinokinin ( 1 ), (?)‐cubebin ( 2 ), (?)‐yatein ( 3 ), (?)‐5‐methoxyyatein ( 4 ), dihydrocubebin ( 5 ) and dihydroclusin ( 6 )) were isolated from Piper cubeba seed extract and evaluated against Schistosoma mansoni. All lignans, except 5 , were able to separate the adult worm pairs and reduce the egg numbers during 24 h of incubation. Lignans 1 , 3 and 4 (containing a lactone ring) were the most efficient concerning antiparasitary activity. Comparing structures 3 and 4 , the presence of the methoxy group at position 5 appears to be important for this activity. Considering 1 and 3 , it is possible to see that the substitution pattern change (methylenedioxy or methoxy groups) in positions 3′ and 4′ alter the biological response, with 1 being the second most active compound. Computational calculations suggest that the activity of compound 4 can be correlated with the largest lipophilicity value. 相似文献
142.
Caroline Van der Heyden Thijs De Mulder Eveline I. P. Volcke Peter Demeyer Marc Heyndrickx Geertui Rasschaert 《Microbial biotechnology》2019,12(4):775-786
In this study, the microbial community structure of two full-scale biotrickling filters treating exhaust air from a pig housing facility were evaluated using 16S metabarcoding. The effect of inoculation with activated sludge of a nearby domestic waste water treatment plant was investigated, which is a cheap procedure and easy to apply in practice. The study was performed at a three-stage and a two-stage full-scale biotrickling filter; of which, only the latter was inoculated. Both biotrickling filters evolved towards a rather similar community over time, which differed from the one in the activated sludge used for inoculation. However, the bacterial population at both biotrickling filters showed small differences on the family level. A large population of heterotrophic bacteria, including denitrifying bacteria, was present in both biotrickling filters. In the non-inoculated biotrickling filter, nitrite-oxidizing bacteria (NOB) could not be detected, which corresponded with the incomplete nitrification leading to high nitrite accumulation observed in this system. Inoculation with the wide spectrum inoculum activated sludge had in this study a positive effect on the biotrickling filter performance (higher ammonia removal and lower nitrous oxide production). It could thus be beneficial to inoculate biotrickling filters in order to enrich NOB at the start-up, making it easier to keep the free nitrous acid concentration low enough to not be inhibited by it. 相似文献
143.
144.
Paulo Vieira Annelies De Clercq Hilde Stals Jelle Van Leene Eveline Van De Slijke Gert Van Isterdael Dominique Eeckhout Geert Persiau Dani?l Van Damme Aurine Verkest José Dijair Antonino de Souza Júnior Nathalie Glab Pierre Abad Gilbert Engler Dirk Inzé Lieven De Veylder Geert De Jaeger Janice de Almeida Engler 《The Plant cell》2014,26(6):2633-2647
145.
Eveline Hürlimann Clarisse A. Houngbedji Richard B. Yapi Prisca B. Ndri Kigbafori D. Silué Gotianwa Soro Ferdinand N. Kouamé Thomas Fürst Jürg Utzinger Eliézer K. N'Goran Giovanna Raso 《PLoS neglected tropical diseases》2014,8(12)
Background
Parasitic infections are still of considerable public health relevance, notably among children in low- and middle-income countries. Measures to assess the magnitude of ill-health in infected individuals, however, are debated and patient-based proxies through generic health-related quality of life (HrQoL) instruments are among the proposed strategies. Disability estimates based on HrQoL are still scarce and conflicting, and hence, there is a need to strengthen the current evidence-base.Methodology
Between November 2011 and February 2012, a national school-based cross-sectional survey was conducted in Côte d''Ivoire. Children underwent parasitological and clinical examination to assess infection status with Plasmodium and helminth species and clinical parameters, and responded to a questionnaire interview incorporating sociodemographic characteristics, self-reported morbidity, and HrQoL. Validity analysis of the HrQoL instrument was performed, assessing floor and ceiling effects, internal consistency, and correlation with morbidity scores. Multivariate regression models were applied to identify significant associations between HrQoL and children''s parasitic infection and clinical status.Principal Findings
Parasitological examination of 4,848 children aged 5–16 years revealed Plasmodium spp., hookworm, Schistosoma haematobium, Schistosoma mansoni, Ascaris lumbricoides, and Trichuris trichiura prevalences of 75.0%, 17.2%, 5.7%, 3.7%, 1.8%, and 1.3%, respectively. Anemic children showed a significant 1-point reduction in self-rated HrQoL on a scale from 0 to 100, whereas no significant negative association between HrQoL and parasite infection was observed. The 12-item HrQoL questionnaire proofed useful, as floor and ceiling effects were negligible, internally consistent (Cronbach''s alpha = 0.71), and valid, as revealed by significant negative correlations and associations with children''s self-reported and clinically assessed morbidity.Conclusions/Significance
Our results suggest that HrQoL tools are not sufficiently sensitive to assess subtle morbidities due to parasitic infection in Ivorian school-aged children. However, more advanced morbid sequelae (e.g., anemia), were measurable by the instrument''s health construct. Further investigations on health impacts of parasitic infection among school-aged children and refinement of generic HrQoL questionnaires are warranted. 相似文献146.
Prior research suggests an association between reduced cerebellar volumes and symptoms of depression and anxiety in patients with mood disorders. However, whether a smaller volume in itself reflects a neuroanatomical correlate for increased susceptibility to develop mood disorders remains unclear. The aim of the present study was to examine the relationship between cerebellar volume and neurotic personality traits in a non-clinical subject sample. 3T Structural magnetic resonance imaging scans were acquired, and trait depression and anxiety scales of the revised NEO personality inventory were assessed in thirty-eight healthy right-handed volunteers. Results showed that cerebellar volume corrected for total brain volume was inversely associated with depressive and anxiety-related personality traits. Cerebellar gray and white matter contributed equally to the observed associations. Our findings extend earlier clinical observations by showing that cerebellar volume covaries with neurotic personality traits in healthy volunteers. The results may point towards a possible role of the cerebellum in the vulnerability to experience negative affect. In conclusion, cerebellar volumes may constitute a clinico-neuroanatomical correlate for the development of depression- and anxiety-related symptoms. 相似文献
147.
148.
Snelders E Camps SM Karawajczyk A Schaftenaar G Kema GH van der Lee HA Klaassen CH Melchers WJ Verweij PE 《PloS one》2012,7(3):e31801
Background
Azoles play an important role in the management of Aspergillus diseases. Azole resistance is an emerging global problem in Aspergillus fumigatus, and may develop through patient therapy. In addition, an environmental route of resistance development has been suggested through exposure to 14α-demethylase inhibitors (DMIs). The main resistance mechanism associated with this putative fungicide-driven route is a combination of alterations in the Cyp51A-gene (TR34/L98H). We investigated if TR34/L98H could have developed through exposure to DMIs.Methods and Findings
Thirty-one compounds that have been authorized for use as fungicides, herbicides, herbicide safeners and plant growth regulators in the Netherlands between 1970 and 2005, were investigated for cross-resistance to medical triazoles. Furthermore, CYP51-protein homology modeling and molecule alignment studies were performed to identify similarity in molecule structure and docking modes. Five triazole DMIs, propiconazole, bromuconazole, tebuconazole, epoxiconazole and difenoconazole, showed very similar molecule structures to the medical triazoles and adopted similar poses while docking the protein. These DMIs also showed the greatest cross-resistance and, importantly, were authorized for use between 1990 and 1996, directly preceding the recovery of the first clinical TR34/L98H isolate in 1998. Through microsatellite genotyping of TR34/L98H isolates we were able to calculate that the first isolate would have arisen in 1997, confirming the results of the abovementioned experiments. Finally, we performed induction experiments to investigate if TR34/L98H could be induced under laboratory conditions. One isolate evolved from two copies of the tandem repeat to three, indicating that fungicide pressure can indeed result in these genomic changes.Conclusions
Our findings support a fungicide-driven route of TR34/L98H development in A. fumigatus. Similar molecule structure characteristics of five triazole DMIs and the three medical triazoles appear the underlying mechanism of cross resistance development. Our findings have major implications for the assessment of health risks associated with the use of triazole DMIs. 相似文献149.
De Temmerman PJ Van Doren EA Verleysen E Van der Stede Y Abi Daoud Francisco M Mast J 《Journal of nanobiotechnology》2012,10(1):24
ABSTRACT: BACKGROUND: The interaction of a nanomaterial (NM) with a biological system depends not only on the sizeof its primary particles but also on the size, shape and surface topology of its aggregates andagglomerates. A method based on transmission electron microscopy (TEM), to visualize theNM and on image analysis, to measure detected features quantitatively, was assessed for itscapacity to characterize the aggregates and agglomerates of precipitated and pyrogenicsynthetic amorphous silicon dioxide (SAS), or silica, NM. RESULTS: Bright field (BF) TEM combined with systematic random imaging and semi-automatic imageanalysis allows measuring the properties of SAS NM quantitatively. Automation allows measuring multiple and arithmetically complex parameters simultaneously on high numbersof detected particles. This reduces operator-induced bias and assures a statistically relevantnumber of measurements, avoiding the tedious repetitive task of manual measurements.Access to multiple parameters further allows selecting the optimal parameter in function of aspecific purpose.Using principle component analysis (PCA), twenty-three measured parameters wereclassified into three classes containing measures for size, shape and surface topology of theNM. CONCLUSION: The presented method allows a detailed quantitative characterization of NM, like dispersionsof precipitated and pyrogenic SAS based on the number-based distributions of their meandiameter, sphericity and shape factor. 相似文献
150.
Suzanne Arends Anneke Spoorenberg Pieternella M Houtman Martha K Leijsma Reinhard Bos Cees GM Kallenberg Henk Groen Elisabeth Brouwer Eveline van der Veer 《Arthritis research & therapy》2012,14(2):1-10