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121.
Hyde JE 《Trends in parasitology》2008,24(8):336-339
The apicomplexan pathogen Cryptosporidium parvum poses major logistical problems in the search for effective drug treatments. These treatments are required urgently because this parasite can cause severe disease and death in immunocompromised individuals and young children. In a recent study, the dependence of Cryptosporidium parasites on a single salvage pathway that leads to essential purine derivatives has been exploited and inhibitors have been identified that selectively target a key enzyme in this salvage process, inosine 5'-monophosphate dehydrogenase. 相似文献
122.
McBriar MD Clader JW Chu I Del Vecchio RA Favreau L Greenlee WJ Hyde LA Nomeir AA Parker EM Pissarnitski DA Song L Zhang L Zhao Z 《Bioorganic & medicinal chemistry letters》2008,18(1):215-219
The design of amide and heteroaryl amide isosteres as replacements for the carbamate substructure in previously disclosed 2,6-disubstituted piperidine N-arylsulfonamides is described. In several cases, amides lessened CYP liabilities in this class of gamma-secretase inhibitors. Selected compounds showed significant reduction of Abeta levels upon oral dosing in a transgenic murine model of Alzheimer's disease. 相似文献
123.
A. J. MacDermott T. Fu R. Nakatsuka A. P. Coleman G. O. Hyde 《Origins of life and evolution of the biosphere》2009,39(5):459-478
In 1996, four α-methyl amino acids in the Murchison meteorite—L-isovaline, L-α-methylnorvaline, L-α-methyl-allo-isoleucine and L-α-methyl-isoleucine—were found to show significant enantiomeric excesses of the L form, ranging from 2% to 9%. Their deuterium
to hydrogen isotope ratios suggest they formed in the pre-solar interstellar gas cloud rather than during a later aqueous
processing phase on the asteroid parent body. In this paper we apply the techniques of the preceding two papers to compute
the parity-violating energy shifts of these amino acids. We find that, in the gas phase, the PVESs of the neutral L forms
of all four Murchison α-methyl amino acids are decisively negative, and there is even some correlation between the magnitudes of the L-excesses and
the magnitudes of the PVESs—all of which is at least consistent with an electroweak origin of the Murchison enantiomeric excesses. 相似文献
124.
Aung Swe Rajesh Jeewon Stephen B. Pointing Kevin D. Hyde 《Biodiversity and Conservation》2009,18(6):1695-1714
Nematode-trapping fungi are ubiquitous in terrestrial habitats in dung, soils, litter and woody debris and they also occur
in freshwater, but only one species has been found in marine habitats. The purpose of this study was therefore to investigate
whether nematode-trapping fungi occurred in mangrove habitats. To achieve this we assessed the diversity of nematode-trapping
fungi on decaying litter from mangroves, freshwater and terrestrial habitats (22 sites) in Hong Kong. Composite samples (n = 1,320) of decaying litter (wood and leaves) were examined and a total of 31 species of nematode-trapping fungi belonging
to four genera, Arthrobotrys, Monacrosporium, and Dactylella were recorded. Twenty-nine species reported in this study are new records for Hong Kong and 16 species are new records from
mangrove habitats worldwide. Nematode trapping fungi are therefore present in marine environments. Commonly encountered taxa
were Arthrobotrys oligospora and Monacrosporium thaumasium which are abundant in all habitats. A. oligospora, M. thaumasium and Arthrobotrys musiformis were frequent (F > 10%). Twenty-six species were rare (0.16–9.32%). Species richness and diversity was higher in terrestrial than in freshwater
and mangrove habitats (ANOVA, P < 0.001). A higher mean diversity was observed on decaying leaves as compared to decaying wood in all habitats (P < 0.001). Based on Shannon diversity index, it was also observed that taxa characterized by adhesive nets were more frequent
in all habitats. This can be explained by the fact that these taxa may have a better competitive saprotrophic ability which
would allow them to compete favourably in nutrient limited environments. Abiotic factors that could be linked to differences
in species diversity between decaying wood and leaves are also discussed. 相似文献
125.
126.
Seed dormancy release and germination of Corispermum lehmannianum Bunge were tested using various treatments: temperature, cold stratification, gibberelins (GA3), dry storage and sand burial. Results showed that temperature and light did not affect the germination of fresh seeds, cold stratification and GA3 could improve seed germination, whereas dry storage and sand burial did not. The germination percentage was highest at 35/20 °C after the cold stratification and GA3 treatments. Corispermum lehmannianum seeds were classified as non-deep, Type-2, physiological dormancy (PD), whose seed dormancy could be released by cold stratification and GA3. 相似文献
127.
128.
K. M. Gruenthal D. A. Witting T. Ford M. J. Neuman J. P. Williams D. J. Pondella II A. Bird N. Caruso J. R. Hyde L. W. Seeb W. A. Larson 《Conservation Genetics》2014,15(1):109-121
Due to severe declines in abundance throughout southern California, the green abalone (Haliotis fulgens Philippi 1845) became protected under a state-sponsored fishery moratorium in 1997 and was declared a NOAA NMFS Species of Concern in 2004. Recently, H. fulgens was chosen for possible stock restoration via translocation of wild adults to depleted habitat and supplementation through releasing cultured individuals. Before a management plan could be developed, however, an understanding of the species’ natural population genetic structure was needed. We used a genomic technique called restriction site associated DNA sequencing (RADSeq) to address the issue. RADSeq enabled discovery of 1,209 single nucleotide polymorphisms theoretically spread genome-wide in H. fulgens. Analyses suggested the species may be panmictic throughout our sampled range, with an effective population size (Ne) of 1,100–3,600. Hence, limitations to management, such as requiring local broodstock and restricting translocation potential, might be unnecessary. Sites with larger populations may be suitable sources for restoration of depleted sites (e.g. the Palos Verdes Peninsula), although the extent of local adaptation remains unknown. Despite this potential for restoration, results gathered on a sample of cultured H. fulgens illustrated how quickly genetic diversity can be lost through captive breeding. To help mitigate a drop in Ne due to hatchery supplementation, we recommend collection and replacement of ≥100 wild abalone per generation for broodstock and close management of the proportion of cultured individuals in the wild. Successful implementation will depend on operational capacity and the resilience of the source populations to broodstock collection. 相似文献
129.
Osvaldo P. Almeida Leon Flicker Stephen Fenner Kate Smith Zoe Hyde David Atkinson Linda Skeaf Roslyn Malay Dina LoGiudice 《PloS one》2014,9(4)
Objective
This study aimed to develop a culturally acceptable and valid scale to assess depressive symptoms in older Indigenous Australians, to determine the prevalence of depressive disorders in the older Kimberley community, and to investigate the sociodemographic, lifestyle and clinical factors associated with depression in this population.Methods
Cross-sectional survey of adults aged 45 years or over from six remote Indigenous communities in the Kimberley and 30% of those living in Derby, Western Australia. The 11 linguistic and culturally sensitive items of the Kimberley Indigenous Cognitive Assessment of Depression (KICA-dep) scale were derived from the signs and symptoms required to establish the diagnosis of a depressive episode according to the DSM-IV-TR and ICD-10 criteria, and their frequency was rated on a 4-point scale ranging from ‘never’ to ‘all the time’ (range of scores: 0 to 33). The diagnosis of depressive disorder was established after a face-to-face assessment with a consultant psychiatrist. Other measures included sociodemographic and lifestyle factors, and clinical history.Results
The study included 250 participants aged 46 to 89 years (mean±SD = 60.9±10.7), of whom 143 (57.2%) were women. The internal reliability of the KICA-dep was 0.88 and the cut-point 7/8 (non-case/case) was associated with 78% sensitivity and 82% specificity for the diagnosis of a depressive disorder. The point-prevalence of a depressive disorder in this population was 7.7%; 4.0% for men and 10.4% for women. Heart problems were associated with increased odds of depression (odds ratio = 3.3, 95% confidence interval = 1.2,8.8).Conclusions
The KICA-dep has robust psychometric properties and can be used with confidence as a screening tool for depression among older Indigenous Australians. Depressive disorders are common in this population, possibly because of increased stressors and health morbidities. 相似文献130.
Nicholas J. Andreas Matthew J. Hyde Chris Gale James R. C. Parkinson Suzan Jeffries Elaine Holmes Neena Modi 《PloS one》2014,9(12)