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Bharath Sundaram Siddhartha Krishnan Ankila J. Hiremath Gladwin Joseph 《Human ecology: an interdisciplinary journal》2012,40(6):931-942
We explored how the forest-dwelling Soliga community of South India views and explains biological invasions, and how local knowledge can inform scientific knowledge on biological invasions. We used an interview schedule with open-ended questions to solicit Soliga opinion on Lantana camara (lantana) invasion. The Soliga cited three reasons for lantana spread: its prolific fruit output and wide seed dispersal, change in fire management, and historical extraction of grass and bamboo. The Soliga believe that lantana invasion has had negative effects on the ecosystem and their livelihoods. Tabling scientific knowledge with local knowledge has improved our understanding of lantana invasion. The role of existing lantana in colonizing neighboring areas, and the response of native tree communities to lantana were common to both local and scientific sources. However, the Soliga view provides a more nuanced perspective of the lantana-fire relationship (contextually based on lantana density) with fires suppressing lantana when lantana density was low. This is contrary to views held by foresters and biologists, that fires are uniformly detrimental and promote lantana. Our study shows that examining Soliga observations has improved understanding of the invasion process and presents avenues for future lantana management. 相似文献
24.
Sampling properties of DNA sequence data in phylogenetic analysis 总被引:20,自引:6,他引:20
We inferred phylogenetic trees from individual genes and random samples of
nucleotides from the mitochondrial genomes of 10 vertebrates and compared
the results to those obtained by analyzing the whole genomes. Individual
genes are poor samples in that they infrequently lead to the whole-genome
tree. A large number of nucleotide sites is needed to exactly determine the
whole-genome tree. A relatively small number of sites, however, often
results in a tree close to the whole-genome tree. We found that blocks of
contiguous sites were less likely to lead to the whole-genome tree than
samples composed of sites drawn individually from throughout the genome.
Samples of contiguous sites are not representative of the entire genome, a
condition that violates a basic assumption of the bootstrap method as it is
applied in phylogenetic studies.
相似文献
25.
Muscular dystrophies (MDs) such as Duchenne muscular dystrophy (DMD), sarcoglycanopathy (Sgpy) and dysferlinopathy (Dysfy)
are recessive genetic neuromuscular diseases that display muscle degeneration. Although these MDs have comparable endpoints
of muscle pathology, the onset, severity and the course of these diseases are diverse. Different mechanisms downstream of
genetic mutations might underlie the disparity in these pathologies. We surmised that oxidative damage and altered antioxidant
function might contribute to these differences. The oxidant and antioxidant markers in the muscle biopsies from patients with
DMD (n = 15), Sgpy (n = 15) and Dysfy (n = 15) were compared to controls (n = 10). Protein oxidation and lipid peroxidation was evident in all MDs and correlated with the severity of pathology, with
DMD, the most severe dystrophic condition showing maximum damage, followed by Sgpy and Dysfy. Oxidative damage in DMD and
Sgpy was attributed to the depletion of glutathione (GSH) and lowered antioxidant activities while loss of GSH peroxidase
and GSH-S-transferase activities was observed in Dysfy. Lower GSH level in DMD was due to lowered activity of gamma-glutamyl
cysteine ligase, the rate limiting enzyme in GSH synthesis. Similar analysis in cardiotoxin (CTX) mouse model of MD showed
that the dystrophic muscle pathology correlated with GSH depletion and lipid peroxidation. Depletion of GSH prior to CTX exposure
in C2C12 myoblasts exacerbated oxidative damage and myotoxicity. We deduce that the pro and anti-oxidant mechanisms could
be correlated to the severity of MD and might influence the dystrophic pathology to a different extent in various MDs. On
a therapeutic note, this could help in evolving novel therapies that offer myoprotection in MD. 相似文献
26.
BACKGROUND: Morbidity management is a core component of the global programme for the elimination of lymphatic filariasis. In a double-blind clinical trial, the tolerability and efficacy of Daflon (500 mg) + DEC (25 mg) or DEC (25 mg) alone, twice daily for 90 days, was studied in 26 patients with bancroftian filarial lymphoedema. RESULTS: None of the patients in either drug group reported any adverse reaction throughout the treatment period (90 days). Haematological and biochemical parameters were within normal limits and there was no significant difference between the pre-treatment (day 0) and post-treatment (day 90) values. The group receiving Daflon showed significant reduction in oedema volume from day 90 (140.6 PlusMinus; 18.8 ml) to day 360 (71.8 PlusMinus; 20.7 ml) compared to the pre-treatment (day 0, 198.4 PlusMinus; 16.5 ml) value. This accounted for a 63.8% reduction in oedema volume by day 360 (considering the pre-treatment (day 0) as 100%). In the DEC group, the changes in oedema volume (between day 1 and day 360) were not significant when compared to the pre-treatment (day 0) value. The percentage reduction at day 360 was only 9%, which was not significant (P > 0.05). CONCLUSION: This study has shown that Daflon (500 mg, twice a day for 90 days) is both safe and efficacious in reducing oedema volume in bancroftian filarial lymphoedema. Further clinical trials are essential for strengthening the evidence base on the role of this drug in the morbidity management of lymphatic filariasis. 相似文献
27.
Harsha Pulleri Kandi Ranganayaki Sathyanarayanan Yale Gowri Dey Gourav Mangalaparthi Kiran K. Yarlagadda Anusha Chandrasekhar Sagar B. K. Mahadevan Anita Srinivas Bharath M. M. Mani Reeta S. 《Neurochemical research》2022,47(6):1610-1636
Neurochemical Research - Rabies is a fatal encephalitis caused by the Rabies lyssavirus (RABV). The presence of minimal neuropathological changes observed in rabies indicates that neuronal... 相似文献
28.
Bharath Ananthasubramaniam Roger M. Nisbet Daniel E. Morse Francis J. Doyle III 《Theoretical Ecology》2011,4(1):69-85
The circa-annual cycle of gametogenesis produces mature gametes at the spawning “season” for successful mass spawning of broadcast
corals. We develop a bioenergetic integrate-and-fire model that reveals how annual insolation rhythms can entrain the gametogenetic
cycles in tropical hermatypic corals to the appropriate spawning season, since photosynthate is their primary source of energy.
In the presence of short-term fluctuations in the energy input, a feedback regulatory mechanism is likely required to achieve
coherence of spawning times to within one lunar cycle, in order for subsequent signals such as lunar and diurnal light cycles
to unambiguously determine the “correct” night of spawning. The feedback mechanism can also provide robustness against population
heterogeneity that may arise due to genetic and environmental effects. We solve the integrate-and-fire bioenergetic model
numerically using the Fokker–Planck equation and use analytical tools such as rotation number to study entrainment. 相似文献
29.
Stahelin RV Digman MA Medkova M Ananthanarayanan B Rafter JD Melowic HR Cho W 《The Journal of biological chemistry》2004,279(28):29501-29512
The regulatory domains of novel protein kinases C (PKC) contain two C1 domains (C1A and C1B), which have been identified as the interaction site for sn-1,2-diacylglycerol (DAG) and phorbol ester, and a C2 domain that may be involved in interaction with lipids and/or proteins. Although recent reports have indicated that C1A and C1B domains of conventional PKCs play different roles in their DAG-mediated membrane binding and activation, the individual roles of C1A and C1B domains in the DAG-mediated activation of novel PKCs have not been fully understood. In this study, we determined the roles of C1A and C1B domains of PKCdelta by means of in vitro lipid binding analyses and cellular protein translocation measurements. Isothermal titration calorimetry and surface plasmon resonance measurements showed that isolated C1A and C1B domains of PKCdelta have opposite affinities for DAG and phorbol ester; i.e. the C1A domain with high affinity for DAG and the C1B domain with high affinity for phorbol ester. Furthermore, in vitro activity and membrane binding analyses of PKCdelta mutants showed that the C1A domain is critical for the DAG-induced membrane binding and activation of PKCdelta. The studies also indicated that an anionic residue, Glu(177), in the C1A domain plays a key role in controlling the DAG accessibility of the conformationally restricted C1A domain in a phosphatidylserine-dependent manner. Cell studies with enhanced green fluorescent protein-tagged PKCdelta and mutants showed that because of its phosphatidylserine specificity PKCdelta preferentially translocated to the plasma membrane under the conditions in which DAG is randomly distributed among intracellular membranes of HEK293 cells. Collectively, these results provide new insight into the differential roles of C1 domains in the DAG-induced membrane activation of PKCdelta and the origin of its specific subcellular localization in response to DAG. 相似文献
30.
Venkateshappa C Harish G Mahadevan A Srinivas Bharath MM Shankar SK 《Neurochemical research》2012,37(8):1601-1614
Oxidative stress and mitochondrial damage are implicated in the evolution of neurodegenerative diseases. Increased oxidative damage in specific brain regions during aging might render the brain susceptible to degeneration. Previously, we demonstrated increased oxidative damage and lowered antioxidant function in substantia nigra during aging making it vulnerable to degeneration associated with Parkinson's disease. To understand whether aging contributes to the vulnerability of brain regions in Alzheimer's disease, we assessed the oxidant and antioxidant markers, glutathione (GSH) metabolic enzymes, glial fibrillary acidic protein (GFAP) expression and mitochondrial complex I (CI) activity in hippocampus (HC) and frontal cortex (FC) compared with cerebellum (CB) in human brains with increasing age (0.01-80 years). We observed significant increase in protein oxidation (HC: p = 0.01; FC: p = 0.0002) and protein nitration (HC: p = 0.001; FC: p = 0.02) and increased GFAP expression (HC: p = 0.03; FC: p = 0.001) with a decreasing trend in CI activity in HC and FC compared to CB with increasing age. These changes were associated with a decrease in antioxidant enzyme activities, such as superoxide dismutase (HC: p = 0.005), catalase (HC: p = 0.02), thioredoxin reductase (FC: p = 0.04), GSH reductase (GR) (HC: p = 0.005), glutathione-s-transferase (HC: p = 0.0001; FC: p = 0.03) and GSH (HC: p = 0.01) with age. However, these parameters were relatively unaltered in CB. We suggest that the regions HC and FC are subjected to widespread oxidative stress, loss of antioxidant function and enhanced GFAP expression during aging which might make them more susceptible to deranged physiology and selective neuronal degeneration. 相似文献