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101.

Aims

L-Aspartate (L-Asp) and D-aspartate (D-Asp) are physiologically important amino acids in mammals and birds. However, the functions of these amino acids have not yet been fully understood. In this study, we therefore examined the effects of L-Asp and D-Asp in terms of regulating body temperature, plasma metabolites and catecholamines in chicks.

Main methods

Chicks were first orally administered with different doses (0, 3.75, 7.5 and 15 mmol/kg body weight) of L- or D-Asp to monitor the effects of these amino acids on rectal temperature during 120 min of the experimental period.

Key findings

Oral administration of D-Asp, but not of L-Asp, linearly decreased the rectal temperature in chicks. Importantly, orally administered D-Asp led to a significant reduction in body temperature in chicks even under high ambient temperature (HT) conditions. However, centrally administered D-Asp did not significantly influence the body temperature in chicks. As for plasma metabolites and catecholamines, orally administered D-Asp led to decreased triacylglycerol and uric acid concentrations and increased glucose and chlorine concentrations but did not alter plasma catecholamines.

Significance

These results suggest that oral administration of D-Asp may play a potent role in reducing body temperature under both normal and HT conditions. The alteration of plasma metabolites further indicates that D-Asp may contribute to the regulation of metabolic activity in chicks.  相似文献   
102.
Malaria control relies heavily on pyrethroid insecticides, to which susceptibility is declining in Anopheles mosquitoes. To combat pyrethroid resistance, application of alternative insecticides is advocated for indoor residual spraying (IRS), and carbamates are increasingly important. Emergence of a very strong carbamate resistance phenotype in Anopheles gambiae from Tiassalé, Côte d''Ivoire, West Africa, is therefore a potentially major operational challenge, particularly because these malaria vectors now exhibit resistance to multiple insecticide classes. We investigated the genetic basis of resistance to the most commonly-applied carbamate, bendiocarb, in An. gambiae from Tiassalé. Geographically-replicated whole genome microarray experiments identified elevated P450 enzyme expression as associated with bendiocarb resistance, most notably genes from the CYP6 subfamily. P450s were further implicated in resistance phenotypes by induction of significantly elevated mortality to bendiocarb by the synergist piperonyl butoxide (PBO), which also enhanced the action of pyrethroids and an organophosphate. CYP6P3 and especially CYP6M2 produced bendiocarb resistance via transgenic expression in Drosophila in addition to pyrethroid resistance for both genes, and DDT resistance for CYP6M2 expression. CYP6M2 can thus cause resistance to three distinct classes of insecticide although the biochemical mechanism for carbamates is unclear because, in contrast to CYP6P3, recombinant CYP6M2 did not metabolise bendiocarb in vitro. Strongly bendiocarb resistant mosquitoes also displayed elevated expression of the acetylcholinesterase ACE-1 gene, arising at least in part from gene duplication, which confers a survival advantage to carriers of additional copies of resistant ACE-1 G119S alleles. Our results are alarming for vector-based malaria control. Extreme carbamate resistance in Tiassalé An. gambiae results from coupling of over-expressed target site allelic variants with heightened CYP6 P450 expression, which also provides resistance across contrasting insecticides. Mosquito populations displaying such a diverse basis of extreme and cross-resistance are likely to be unresponsive to standard insecticide resistance management practices.  相似文献   
103.
Inhibition of α-amylase is an important strategy to control post-prandial hyperglycemia. The present study on Ruellia tuberosa, known as traditional anti-diabetic agent, is being provided in silico study to identify compounds inhibiting α-amylase in rat and human. Compounds were explored from PubChem database. Molecular docking was studied using the autodock4. The interactions were further visualized and analyzed using the Accelrys Discovery Studio version 3.5. Binding energy of compounds to α-amylase was varying between -1.92 to -6.66 kcal/mol in rat pancreatic alpha amylase and -3.06 to -8.42kcal/mol in human pancreatic alpha amylase, and inhibition konstanta (ki) was varying between 13.12- 39460µM in rat and 0.67-5600µM in human. The docking results verify that betulin is the most potential inhibitor of all towards rat model alpha amylase and human alpha amylase. Further analysis reveals that betulin could be a potential inhibitor with non-competitive pattern like betulinic acid. In comparison, betulin has smaller Ki (0.67µM) than acarbose (2.6 µM), which suggesting that betulin is more potential as inhibitor than acarbose, but this assumption must be verified in vitro.  相似文献   
104.
Neuroblastomas (NBs) are a clinically heterogeneous group of extra cranial pediatric tumors. Patients with high-risk, metastatic NBs have a long-term survival rate of below 40%, and are often resistant to current therapeutic modalities. Due to toxic side effects associated with radiation and chemotherapies, development of new agents is warranted to overcome resistance and effectively treat this disease in clinic. CARP-1 functional mimetics (CFMs) are an emerging class of small molecule compounds that inhibit growth of diverse cancer cell types. Here we investigated NB inhibitory potential of CFMs and the molecular mechanisms involved. CFM-1, -4, and -5 inhibited NB cell growth, in vitro, independent of their p53 and MYCN status. CFM-4 and -5 induced apoptosis in NB cells in part by activating pro-apoptotic stress-activated kinases (SAPKs) p38 and JNK, stimulating CARP-1 expression and cleavage of PARP1, while promoting loss of the oncogenes C and N-myc as well as mitotic cyclin B1. Treatments of NB cells with CFM-4 or -5 also resulted in loss of Inhibitory κB (IκB) α and β proteins. Micro-RNA profiling revealed upregulation of XIAP-targeting miR513a-3p in CFM-4-treated NB, mesothelioma, and breast cancer cells. Moreover, exposure of NB and breast cancer cells to CFM-4 or -5 resulted in diminished expression of anti-apoptotic XIAP1, cIAP1, and Survivin proteins. Expression of anti-miR513a-5p or miR513a-5p mimic, however, interfered with or enhanced, respectively, the breast cancer cell growth inhibition by CFM-4. CFMs also impacted biological properties of the NB cells by blocking their abilities to migrate, form colonies in suspension, and invade through the matrix-coated membranes. Our studies indicate anti-NB properties of CFM-4 and 5, and suggest that these CFMs and/or their future analogs have potential as anti-NB agents.  相似文献   
105.
106.
On a population level, individual plasticity in reproductive phenology can provoke either anticipations or delays in the average reproductive timing in response to environmental changes. However, a rigid reliance on photoperiodism can constraint such plastic responses in populations inhabiting temperate latitudes. The regulation of breeding season length may represent a further tool for populations facing changing environments. Nonetheless, this skill was reported only for equatorial, nonphotoperiodic populations. Our goal was to evaluate whether species living in temperate regions and relying on photoperiodism to trigger their reproduction may also be able to regulate breeding season length. During 10 years, we collected 2,500 female reproductive traits of a mammal model species (wild boar Sus scrofa) and applied a novel analytical approach to reproductive patterns in order to observe population-level variations of reproductive timing and synchrony under different weather and resources availability conditions. Under favorable conditions, breeding seasons were anticipated and population synchrony increased (i.e., shorter breeding seasons). Conversely, poor conditions induced delayed and less synchronous (i.e., longer) breeding seasons. The potential to regulate breeding season length depending on environmental conditions may entail a high resilience of the population reproductive patterns against environmental changes, as highlighted by the fact that almost all mature females were reproductive every year.  相似文献   
107.
A single system is presented, where both genetic and epigenetic control of tumor induction can be studied at the same time. This system is offered by the amphidiploid tumorous hybrid Nicotiana glauca × N. langsdorffii, a nontumorous mutant of it and the nontumorous parent species N. glauca and N. langsdorffii. The aim of the present paper is to compare long-term in vitro cultures of tumorous (genetic and habituated), and nontumorous strains, through the characterization of their genomes according to several physico-chemical parameters. The data reported show that both qualitative and quantitative differences in DNA complexity are correlated with the tumorous transformation. Particularly, a high degree of mismatching between the DNAs of the tumorous and nontumorous hybrids and the lack, in the second genotype (nontumorous), of three DNA peaks in Ag+?Cs2SO4 analytical ultracentrifugation profile seem to support the hypothesis, suggested in a previous paper, of the presence, in the nontumorous mutant, of a gross chromosomal rearrangement, probably a deletion. Amplification and underreplication of specific sequences also seemed to be correlated with changes from the normal to the tumorous state, highly repetitive sequences being present in higher amounts in the normal strains and in the habituated N. glauca than in the case of the tumorous hybrid. Finally, DNA bound ion contents were found to be strikingly higher in tumorous than in nontumorous tissues. The results are discussed in the frame of the general hypothesis of high somatic genomic plasticity in plants.  相似文献   
108.
We evaluated the response of eight economically important Croatian grapevine cultivars and studied the impact of their sanitary status on in vitro introduction, by comparing the response of healthy and virus-infected genotypes of one cultivar. Nodal explant survival on three media, M1 (half-strength MS), M2 (full-strength MS) or M3 (full-strength MS with 4.4 µM L?1 benzylaminopurine) was measured after 2 weeks and regrowth after 8 weeks. After 8 weeks, average shoot length and node number were significantly higher on M2 compared to M1 and M3. M3 induced significantly shorter average internode length, compared to M1 and M2. Survival of one healthy and of five cultivar Plavac mali genotypes infected with GFLV, GLRaV-1, GLRaV-3, GLRaV-3+GVA and GLRaV-1+GLRaV-3 was 97.5 and 82.8–87.5%, respectively. Regrowth of the healthy genotype reached 95.5%, but dropped to 5.5–31.4% in infected ones. The healthy genotype showed significantly higher shoot length (6.3 cm) and node number (7.3) compared to infected genotypes, with shoot length between 1.2–2.6 cm and node number between 1.2–3.0. By contrast, internode length was not significantly different between the healthy and the infected genotypes. The present work represents the first successful in vitro introduction for three of the eight native Croatian cultivars studied.  相似文献   
109.
Bryophytes are a diverse group of organisms with unique properties, yet they are severely underrepresented in plant trait databases. Building on the recently published European Red List of bryophytes and previous trait compilations, we present the Bryophytes of Europe Traits (BET) data set, including biological traits such as those related to life history, growth habit, sexual and vegetative reproduction; ecological traits such as indicator values, substrate and habitat; and bioclimatic variables based on the species' European range. The data set includes values for 65 traits and 25 bioclimatic variables, containing more than 135,000 trait values with a completeness of 82.7% on average. The data set will enable future studies in bryophyte biology, ecology and conservation, and may help to answer fundamental questions in bryology.  相似文献   
110.
Previous studies have shown that prepupae/pupae and dust/frass from Hypothenemus hampei (Ferrari) reared on coffee berries were attractive to its parasitoid Prorops nasuta Waterston, while the same biological materials obtained from an artificial diet were not. In this study, we identified the volatiles from prepupae/pupae and dust/frass from H. hampei reared on Coffea canephora Pierre ex Froehner berries and artificial diet by gas chromatography coupled with mass spectrometry (GC?CMS), evaluated their behavioural activity, and investigated the possible origin of the kairomones in the H. hampei dust/frass attractive to P. nasuta. The GC?CMS analysis indicated that 24 peaks were consistently present in the headspace volatiles of dust/frass from H. hampei reared on coffee berries, 18 of these peaks were identified. Nineteen compounds were found in the dust/frass from H. hampei reared on an artificial diet. The compounds 1-octen-3-ol, limonene, n-tridecane, n-tetradecane, longifolene, n-pentadecane and n-heptadecane were common in dust/frass from H. hampei reared on coffee berries and artificial diet. Parasitoids were more attracted to 3-octanone, limonene, longifolene and n-dodecane compared to clean air. In contrast, P. nasuta preferred clean air to n-tetradecane. The rest of the compounds did not influence the behaviour of parasitoids. Two compounds were released by prepupae/pupae from H. hampei obtained from coffee berries, whereas six compounds were emitted by prepupae/pupae from the artificial diet. The compounds n-hexadecane and n-heptadecane were found in both types of prepupae/pupae. Parasitoids were more attracted to n-hexadecane than to clean air. In contrast, females did not show any preference for n-heptadecane or clean air. Among the compounds identified from dust/frass from H. hampei attractive to P. nasuta, only longifolene was found in the healthy C. canephora berry volatiles. Four species of fungi were isolated from the dust/frass of H. hampei, including Fusarium solani (Mart.) Sacc., Penicillium crustosum Thom, Aspergillus aculeatus lizuka and Mucor sp. Among the compounds identified in the dust/frass from H. hampei attractive to P. nasuta females, only 3-octanone was detected in the volatiles from F. solani and P. crustosum.  相似文献   
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