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1.
Economic Botany - The Use of “Use Value”: Quantifying Importance in Ethnobotany. Use value (UV) is an index widely used to quantify the relative importance of useful plants. It combines...  相似文献   
2.
It is generally accepted that a majority of individuals infected by Entamoeba histolytica do not develop symptomatic disease. However, the parasite and the host factors contributing to the development of the disease, remain undetermined. It is also unclear why certain individuals develop extra-intestinal amebiasis without exhibiting apparent intestinal symptoms. An outbreak of amebic liver abscess in Tbilisi, Georgia in 1998-1999 suggested that the causative E. histolytica strain had an unusual propensity for extra-intestinal spread. To correlate the genetic differences with pathogenic potential of the parasite, we have examined the SREHP gene polymorphisms among Georgian E. histolytica isolates. Comparison of polymorphic patterns revealed the presence of several different genotypes of E. histolytica, thus preventing an association of a single genotype with hepatic disease, but supporting the previous finding of extensive genetic diversity among E. histolytica isolates from the same geographic origin.  相似文献   
3.
Interaction between killer cell immunoglobulin-like receptors (KIR) and cognate HLA class I ligands influences the innate and adaptive immune response to infection. The KIR family varies in gene content and allelic polymorphism, thereby, distinguishing individuals and populations. KIR gene content was determined for 230 individuals from three Amerindian tribes from Venezuela: the Yucpa, Bari and Warao. Gene-content haplotypes could be assigned to 212 individuals (92%) because only five different haplotypes were present—group A and four group B. Six different haplotype combinations accounted for >80% of individuals. Each tribe has distinctive genotype frequencies. Despite few haplotypes, all 14 KIR genes are at high frequency in the three tribes, with the exception of 2DS3. Each population has an even frequency of group A and B haplotypes. Allele-level analysis of 3DL1/S1 distinguished five group A haplotypes and six group B haplotypes. The high frequency and divergence of the KIR haplotypes in the Amerindian tribes provide greater KIR diversity than is present in many larger populations. An extreme case being the Yucpa, for whom two gene-content haplotypes account for >90% of the population. These comprise the group A haplotype and a group B haplotype containing all the KIR genes, except 2DS3, that typify the group B haplotypes. Here is clear evidence for balancing selection on the KIR system and the biological importance of both A and B haplotypes for the survival of human populations.Electronic Supplementary Material Supplementary material is available for this article at  相似文献   
4.
The aim of this work was to study the role of H3O+ and transition-metal (TM) ions in keto-enol and amino-imino tautomeric transitions in DNA base pairs and depurination. In this regard, we discuss the thermodynamic model of ion-DNA interactions and UV display of double-proton transfer (DPT) in GC. The probabilities and energies of rare tautomeric forms of GC pairs in DNA induced by H3O+ and TMwere determined being in the range from0.02 (forMg2+) to 1 ( forCu2+), and from 0 kcal/m (for Cu2+) to 2.3 kcal/m (for Mg2+), respectively. It was shown that 3'ACC5'/5'TGG3' site of DNA double helix, which corresponds to the only triplet 5'UGG3' of RNA that codes the most valuable amino acid tryptophan, is a good target for TM ions to attack. It was also shown that the only way to obtain the tryptophan-coding 5'UGG3' triplet in RNA via transition-type G --> A point mutation caused by TM ions is their interaction with the site of a DNA double helix, which corresponds to 5'CGG3' triplet of RNA that codes arginine.  相似文献   
5.
Disturbances in natural Circadian rhythm are well-known stress factors, affecting a range of metabolic pathways in the living body including the brain. Hence, discovery of natural compounds that could help to prevent and cure of adverse changes is very important. One of the recently discussed substances is creatine, that is believed to have anti-stressor properties. Recent paper describes the impact of intraperitoneally injected creatine (140 mg/kg) into rats with a disturbed natural circadian rhythm for an extended period of time (30 days). Markedly, creatine-treated animals show positive changes in open-field behavioral parameters, and an increase in certain antioxidant enzymes’ (SOD, catalase) activity in the hippocampus, whereas the concentration of nitric oxide, H2O2, and Ca2+ are approximated to the control value. Similar findings were also observed in case of Na+/K+- and Ca2+-ATPases. To sum up, the recent findings allow the conclusion that oxidative stress induced by long-term disturbances in natural circadian rhythm is accompanied and likely provoked by an increase in Ca2+-cytotoxicity, which is supposedly normalized by the creatine’s indirect action on the NMDA receptor. Therefore, impact on energy mediating pathways has a positive effect on stabilization of antioxidant and various metabolic systems and protecting hippocampal cells from stress.  相似文献   
6.
The intensity of lipid peroxidation and activity of antioxidant system enzymes in the blood plasma, brain and cardial muscle of laboratory rats under 40 days of isolation and violation of diurnal cycle was studied. The obtained data show that on the background of concentration changes in NO changes also take place in the intensity of lipid peroxidation process, indicated by changes in the concentration of TBA-active products and diene conjugates. The changes taking place in the activity of superoxidedismutase, catalase, succinatdehydrogenase, creatine kinase and aldolase under stress were studied. The resulting data show that isolation of animals and violation of diurnal cycle are the factors causing a significant reduction in the energy metabolism in the brain and heart tissue cells and resulting in oxidative stress that, in its turn, may become the reason for development of toxic radicals. Furthermore, prolonged stress may result in irreversible processes that are considered to be the reasons for significant pathologies of the cardiovascular system.  相似文献   
7.
The energetics of Cu (II) ion binding to mononucleosomes from C3HA mice liver and ascitic hepatoma 22A cells was determined from their binding isotherms by equilibrium dialysis and pulse high frequency inductively coupled plasma atomic emission spectroscopy. Anticooperative binding of copper ions with normal and tumor mononucleosomes were observed under various NaCl concentrations (0.002; 0.02; 0.2 M). The binding constants of Cu(II) ion with normal mononucleosomes in 0.002, 0.02, 0.2 M NaCl are 6.10×104,5.22×104,4.31×104 respectively. The binding constants of Cu(II) ion with tumor mononucleosomes in 0.002, 0.02, 0.2 M NaCl are 6.68×104,6.12×104,4.82×104 respectively.  相似文献   
8.
We have designed and synthesized several structural isomers of anthramycin (heterocycles 2, 3, 5, 6, and 8) and found that, in particular, pyrrolobenzodiazepine 8 induces DNA cleavage and formation of small fragments of DNA. The cytotoxic effects of 8 were manifested with both non-transformed primary neuronal/glial cells and transformed Jurkat cells. The other compounds did not change the viability either of transformed or of non-transformed cells, and induced DNA cleavage to a lesser extent.  相似文献   
9.
Atopic dermatitis (AD) is a common skin disease of complex etiology including affected humoral and cellular immune responses. The role of NK cells in development of this disease has been recently postulated, but is still poorly documented. The current study was undertaken to determine the impact of genes for the most polymorphic NK cell receptors, known as killer cell immunoglobulin-like receptors (KIRs), on the development of AD.  相似文献   
10.

Background

Updated estimates of measles case fatality rates (CFR) are critical for monitoring progress towards measles elimination goals. India accounted for 36% of total measles deaths occurred globally in 2011. We conducted a retrospective cohort study to estimate measles CFR and identify the risk factors for measles death in Bihar–one of the north Indian states historically known for its low vaccination coverage.

Methods

We systematically selected 16 of the 31 laboratory-confirmed measles outbreaks occurring in Bihar during 1 October 2011 to 30 April 2012. All households of the villages/urban localities affected by these outbreaks were visited to identify measles cases and deaths. We calculated CFR and used multivariate analysis to identify risk factors for measles death.

Results

The survey found 3670 measles cases and 28 deaths (CFR: 0.78, 95% confidence interval: 0.47–1.30). CFR was higher among under-five children (1.22%) and children belonging to scheduled castes/tribes (SC/ST, 1.72%). On multivariate analysis, independent risk factors associated with measles death were age <5 years, SC/ST status and non-administration of vitamin A during illness. Outbreaks with longer interval between the occurrence of first case and notification of the outbreak also had a higher rate of deaths.

Conclusions

Measles CFR in Bihar was low. To further reduce case fatality, health authorities need to ensure that SC/ST are targeted by the immunization programme and that outbreak investigations target for vitamin A treatment of cases in high risk groups such as SC/ST and young children and ensure regular visits by health-workers in affected villages to administer vitamin A to new cases.  相似文献   
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