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941.
Devi Stuart-Fox 《Evolutionary ecology》2009,23(3):425-433
Rensch’s rule describes a pattern of allometry in sexual size dimorphism (SSD): when males are the larger sex (male-biased
SSD), SSD increases with increasing body size, and when females are the larger sex (female-biased SSD), SSD decreases with
increasing body size. While this expectation generally holds for taxa with male-biased or mixed SSD, examples of allometry
for SSD consistent with Rensch’s rule in groups with primarily female-biased SSD are remarkably rare. Here, I show that the
majority of dwarf chameleons (Bradypodion spp.) have female-biased SSD. In accordance with Rensch’s rule, the group exhibits an allometric slope of log(female size)
on log(male size) less than one, although statistical significance is dependent on the phylogenetic comparative method used.
In this system, this pattern is likely due to natural selection on both male and female body size, combined with fecundity
selection on female body size. In addition to quantifying SSD and testing Rensch’s rule in dwarf chameleons, I discuss reasons
why Rensch’s rule may only rarely apply to taxa with female-biased SSD. 相似文献
942.
Uma Devi Bommu Kranthi Kumar Konidala Neeraja Pabbaraju 《Journal of receptor and signal transduction research》2017,37(6):600-610
The present study was to explore expectation and examination of therapeutic potential quercetin analogs as efficient anticancer agents against human epidermal growth factor receptor (EGFR), which is a consistent hallmark for moderating the non-small-cell lung carcinoma (NSCLC). Here, ligand-based virtual screening, pharmacophore approach and molecular docking were established as rational strategies for recognition of small analogs against the ligand binding domain of EGFR (PDB code: 1XKK). Adverse effects, toxicogenomics and pharmacokinetics reported that 10 candidates showed reliable consequences with less side effects and more efficient for target receptor. Protein–ligand interaction profiles revealed that the probable H-bonds, atomic-π contacts, salt bridges and van der Waals interactions sustain the complexity and stability of receptor structure; thus, they could complicate to generate single alteration acquired for drug resistance. In silico anticancer properties explain the lead scaffolds which are assumed to be flexible and experimentally proved chemicals. The overall consequences indicated that recognized leads could be utilized as reference skeletons for new inhibitors envisaging toward EGFR to ameliorate NSCLC and other malignant disorders. 相似文献
943.
D S Gonzalez K Karaveg A S Vandersall-Nairn A Lal K W Moremen 《The Journal of biological chemistry》1999,274(30):21375-21386
944.
The primary sites for occurrence of oral cancer include the buccal mucosa, tongue, alveolus, palate, lip and the floor of the mouth. In this study, an attempt was made to estimate the cytogenetic damage in different regions of the oral mucosa in people habituated to smoking beedi,which is one of the major forms of tobacco consumption in India and believed to be a major risk factor for oral cancer. By using the micronucleus assay on exfoliated cells from the buccal mucosa, palate and tongue of beedi smokers, we examined an early cellular response to the effect of beedi smoking. A total number of 50 randomly selected male subjects were included in the study. Case and control groups (smokers and non-smokers, respectively) comprised 25 subjects each. The difference in mean micronucleated cell count between cases and controls was significant (P <0.01) for buccal mucosa and palate, but not for tongue. The correlation between age and micronucleus cell count was weak for both cases (r=0.27) and controls (r=0.36). 相似文献
945.
946.
947.
Luhariya RK Lal KK Singh RK Mohindra V Punia P Chauhan UK Gupta A Lakra WS 《Molecular biology reports》2012,39(4):3659-3665
The present study examined partial cytochrome b gene sequence of mitochondrial DNA for polymorphism and its suitability to determine the genetic differentiation in wild
Labeo rohita. The 146 samples of L. rohita were collected from nine distant rivers; Satluj, Brahmaputra, Son, Chambal Mahanadi, Rapti, Chauka, Bhagirathi and Tons were
analyzed. Sequencing of 307 bp of Cyto b gene revealed 35 haplotypes with haplotype diversity 0.751 and nucleotide diversity (π) 0.005. The within population variation
accounted for 84.21% of total variation and 15.79% was found to among population. The total Fst value, 0.158 (P < 0.05) was found to be significant. The results concluded that the partial cyto b is polymorphic and can be a potential marker to determining genetic stock structure of L. rohita wild population. 相似文献
948.
Goel HL Bae D Pursell B Gouvin LM Lu S Mercurio AM 《Development (Cambridge, England)》2011,138(14):2969-2976
Although the neuropilins were characterized as semaphorin receptors that regulate axon guidance, they also function as vascular endothelial growth factor (VEGF) receptors and contribute to the development of other tissues. Here, we assessed the role of NRP2 in mouse mammary gland development based on our observation that NRP2 is expressed preferentially in the terminal end buds of developing glands. A floxed NRP2 mouse was bred with an MMTV-Cre strain to generate a mammary gland-specific knockout of NRP2. MMTV-Cre;NRP2(loxP/loxP) mice exhibited significant defects in branching morphogenesis and ductal outgrowth compared with either littermate MMTV-Cre;NRP2(+/loxP) or MMTV-Cre mice. Mechanistic insight into this morphological defect was obtained from a mouse mammary cell line in which we observed that VEGF(165), an NRP2 ligand, induces branching morphogenesis in 3D cultures and that branching is dependent upon NRP2 as shown using shRNAs and a function-blocking antibody. Epithelial cells in the mouse mammary gland express VEGF, supporting the hypothesis that this NRP2 ligand contributes to mammary gland morphogenesis. Importantly, we demonstrate that VEGF and NRP2 activate focal adhesion kinase (FAK) and promote FAK-dependent branching morphogenesis in vitro. The significance of this mechanism is substantiated by our finding that FAK activation is diminished significantly in developing MMTV-Cre;NRP2(loxP/loxP) mammary glands compared with control glands. Together, our data reveal a VEGF/NRP2/FAK signaling axis that is important for branching morphogenesis and mammary gland development. In a broader context, our data support an emerging hypothesis that directional outgrowth and branching morphogenesis in a variety of tissues are influenced by signals that were identified initially for their role in axon guidance. 相似文献
949.
Tripti Singh Shalini Sharma Rajeev Singh Dan Bahadur Pal Irfan Ahmad Mohammad Mahtab Alam Nand Lal Singh Manish Srivastava Neha Srivastava 《Luminescence》2023,38(7):999-1010
Nanomaterials are gaining enormous interests due to their novel applications that have been explored nearly in every field of our contemporary society. In this scenario, preparations of nanomaterials following green routes have attracted widespread attention in terms of sustainable, reliable, and environmentally friendly practices to produce diverse nanostructures. In this review, we summarize the fundamental processes and mechanisms of green synthesis approaches of TiO2 nanoparticles (NPs). We explore the role of plants and microbes as natural bioresources to prepare TiO2 NPs. Particularly, focus has been made to explore the potential of TiO2-based nanomaterials to design a variety of sensing platforms by exploiting the photocatalysis efficiency under the influence of a light source. These types of sensing are of massive importance for monitoring environmental pollution and therefore for inventing advanced strategies to remediate hazardous pollutants and offer a clean environment. 相似文献
950.
Abstract The calculated phonon spectrum of Z-form poly(dG-dC)·poly(dG-dC) between 400 and 1600 cm?1 is reported. Comparison with the available data shows the very good agreement between theory and experiment. The eigenvector displacement is used to assign the characteristics of some of the important modes. 相似文献