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排序方式: 共有361条查询结果,搜索用时 171 毫秒
81.
82.
Muhammad Hammad Aziz M. Fakhar-e-Alam Mahvish Fatima Fozia Shaheen Seemab Iqbal M. Atif Muhammad Talha Syed Mansoor Ali Muhammad Afzal Abdul Majid Thamir Shelih Al.Harbi Muhammad Ismail Zhiming M. Wang M. S. AlSalhi Z. A. Alahmed 《PloS one》2016,11(3)
Nickel nanomaterials are promising in the biomedical field, especially in cancer diagnostics and targeted therapy, due to their distinctive chemical and physical properties. In this experiment, the toxicity of nickel nanotubes (Ni NTs) were tested in an in vitro cervical cancer model (HeLa cell line) to optimize the parameters of photodynamic therapy (PDT) for their greatest effectiveness. Ni NTs were synthesized by electrodeposition. Morphological analysis and magnetic behavior were examined using a Scanning electron microscope (SEM), an energy dispersive X-ray analysis (EDAX) and a vibrating sample magnetometer (VSM) analysis. Phototoxic and cytotoxic effects of nanomaterials were studied using the Ni NTs alone as well as in conjugation with aminolevulinic acid (5-ALA); this was performed both in the dark and under laser exposure. Toxic effects on the HeLa cell model were evaluated by a neutral red assay (NRA) and by detection of intracellular reactive oxygen species (ROS) production. Furthermore, 10–200 nM of Ni NTs was prepared in solution form and applied to HeLa cells in 96-well plates. Maximum toxicity of Ni NTs complexed with 5-ALA was observed at 100 J/cm2 and 200 nM. Up to 65–68% loss in cell viability was observed. Statistical analysis was performed on the experimental results to confirm the worth and clarity of results, with p-values = 0.003 and 0.000, respectively. Current results pave the way for a more rational strategy to overcome the problem of drug bioavailability in nanoparticulate targeted cancer therapy, which plays a dynamic role in clinical practice. 相似文献
83.
A L Meredith S M Huson P W Lunt M Sarfarazi H G Harley J D Brook D J Shaw P S Harper 《BMJ (Clinical research ed.)》1986,293(6558):1353-1356
The close genetic linkage between the loci for apolipoprotein CII (ApoC2) and myotonic dystrophy makes ApoC2 the closest fully validated marker for prediction of myotonic dystrophy. Application to genetic counselling and presymptomatic and prenatal prediction is reported in seven families with myotonic dystrophy, including one case in which the disorder was excluded prenatally. Only one of the families did not have members with ApoC2 genotypes that allowed prediction, but careful clinical study of older family members was found to be an important factor. ApoC2 typing of families with myotonic dystrophy should be of practical help both in prediction for asymptomatic relatives and for prenatal diagnosis in pregnancies of an affected parent. 相似文献
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Rona Cabo Sigrunn Hernes Audun Slettan Margaretha Haugen Shu Ye Rune Blomhoff M. Azam Mansoor 《Genes & nutrition》2015,10(3)
Data on the effect of combined genetic polymorphisms, involved in folate metabolism, on the concentration of serum folate after folic acid supplementation are scarce. Therefore, we investigated the impact of seven gene polymorphisms on the concentration of serum folate and p-tHcy in healthy subjects after short-term folic acid supplementation. In a randomized, double blind, crossover study, apparently healthy subjects were given either 0.8 mg folic acid per day (n = 46) or placebo (n = 45) for 14 days. The washout period was 14 days. Fasting blood samples were collected on day 1, 15, 30 and 45. Data on subjects on folic acid supplementation (n = 91) and on placebo (n = 45) were used for the statistical analysis. The concentration of serum folate increased higher in subjects with higher age (53.5 ± 7.0 years) than in subjects with lower age (24.3 ± 3.2 years) after folic acid supplementation (p = 0.006). The baseline concentration of serum folate in subjects with polymorphism combination, reduced folate carrier protein, RFC1-80 GA and methylenetetrahydrofolate reductase, MTHFR677 CT+TT, was lower than RFC1-80 AA and MTHFR677 CT+TT (p = 0.002). After folic acid supplementation, a higher increase in the concentration of serum folate was detected in subjects with polymorphism combination RFC1-80 GA and MTHFR677 CC than RFC1-80 GG and MTHFR CT+TT combination (p < 0.0001). The baseline concentration of plasma total homocysteine (p-tHcy) was altered by combined polymorphisms in genes associated with folate metabolism. After folic acid supplementation, in subjects with combined polymorphisms in methylenetetrahydrofolate dehydrogenase, MTHFD1-1958 and MTHFR-677 genes, the concentration of p-tHcy was changed (p = 0.002). The combination of RFC1-80 and MTHFR-677 polymorphisms had a profound affect on the concentration of serum folate in healthy subjects before and after folic acid supplementation. 相似文献
87.
Muhammad Mudassir Mansoor Muhammad Afzal Abu Bakar M. Raza Zeeshan Akram Adil Waqar Muhammad Babar Shahzad Afzal 《Saudi Journal of Biological Sciences》2015,22(3):317-321
Chrysoperla carnea (Stephens) is an important biological control agent currently being used in many integrated pest management (IPM) programs to control insect pests. The effect of post-treatment temperature on insecticide toxicity of a spinosyn (spinosad), pyrethroid (lambda cyhalothrin), organophosphate (chlorpyrifos) and new chemistry (acetamiprid) to C. carnea larvae was investigated under laboratory conditions. Temperature coefficients of each insecticide tested were evaluated. From 20 to 40 °C, toxicity of lambda cyhalothrin and spinosad decreased by 2.15- and 1.87-fold while toxicity of acetamiprid and chlorpyrifos increased by 2.00 and 1.79-fold, respectively. The study demonstrates that pesticide effectiveness may vary according to environmental conditions. In cropping systems where multiple insecticide products are used, attention should be given to temperature variation as a key factor in making pest management strategies safer for biological control agents. Insecticides with a negative temperature coefficient may play a constructive role to conserve C. carnea populations. 相似文献
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Min C Ohta K Kajiya M Zhu T Sharma K Shin J Mawardi H Howait M Hirschfeld J Bahammam L Ichimonji I Ganta S Amiji M Kawai T 《Peptides》2012,36(2):151-156
The present study examined the antimicrobial activity of the peptide ghrelin. Both major forms of ghrelin, acylated ghrelin (AG) and desacylated ghrelin (DAG), demonstrated the same degree of bactericidal activity against Gram-negative Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa), while bactericidal effects against Gram-positive Staphylococcus aureus (S. aureus) and Enterococcus faecalis (E. faecalis) were minimal or absent, respectively. To elucidate the bactericidal mechanism of AG and DAG against bacteria, we monitored the effect of the cationic peptides on the zeta potential of E. coli. Our results show that AG and DAG similarly quenched the negative surface charge of E. coli, suggesting that ghrelin-mediated bactericidal effects are influenced by charge-dependent binding and not by acyl modification. Like most cationic antimicrobial peptides (CAMPs), we also found that the antibacterial activity of AG was attenuated in physiological NaCl concentration (150mM). Nonetheless, these findings indicate that both AG and DAG can act as CAMPs against Gram-negative bacteria. 相似文献
90.
Twenty years ago, scientists predicted that better understanding of fiber development would lead to novel ways to engineer superior cotton fiber. Advances in genetic resources, DNA markers, DNA sequence information, and gene expression data have indeed provided new insights into fiber initiation, elongation and maturation. Many exciting applications of this knowledge offer the potential to select better cotton genotypes more effectively in mainstream breeding programs or engineer genotypes with improved agronomic and/or quality traits. Here, we discuss recent progress in understanding genes involved in fiber development, and their regulation and manipulation to engineer improved fibers. Better understanding of quantitative trait loci/gene interactions that influence fiber quality and yield may help to tailor superior cotton genotypes to diverse environments. 相似文献