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81.
Cervical cancer continues to be the most common cause of death among women in developing countries. Methylenetetrahydrofolate reductase (MTHFR) and methionine synthase (MS) are critical enzymes of folate metabolic pathways. In this work, we have conducted a case–control study to assess the role of these two polymorphisms in cervical cancer development. We obtained blood samples from 200 women with cervical cancer and from equal matched controls and analysed using PCR-RFLP method. We found that the methylenetetrahydrofolate reductase variant CT and CT + TT genotypes decreased cervix cancer risk, statistically significant (OR:0.30, 95% CI: 0.18–0.51, P < 0.001 for CT and OR:0.29, 95% CI: 0.18–0.49, P = 0.0000006 for CT + TT). Similarly in those patients who used oral contraceptive with variant CT genotype, there was statistically highly significant reduced risk of cervix cancer (OR:0.25, 95% CI: –0.12–0.49, P < 0.001) of methylenetetrahydrofolate reductase gene. For the methionine synthase, 2756 variant AG and AG + GG genotypes were similarly associated with highly significant reduced risk of cervix cancer (OR: 0.13, 95% CI: 0.07–0.26, P < 0.001 for AG, and OR: 0.15, 95% CI: 0.08–0.27, P < 0.001 for AG + GG) genotypes. In conclusion, our study suggested that methylenetetrahydrofolate reductase and methionine synthase polymorphisms might have protective effect on the risk of cervical cancer in the North Indian women.  相似文献   
82.
A study in 2000-2001 of causes of death of women of reproductive age (15-49) in the West Bank, Palestinian Occupied Territories, found that 154 of the 411 deceased women aged 15-49 with known marital status were single. Death notification forms for reported deaths were analysed and verbal autopsies carried out, where possible, with relatives of the deceased women. We found important differences in the age at death and causes of death among the single and married women, which can be attributed to the disadvantaged social status of single women in Palestinian society, exacerbated by the current unstable political situation. 41% of the deceased single women were under 25 years of age at death compared to 8% of the married women. The proportion of violent deaths and suicides among the single women was almost twice as high as among the married women, mainly in those below age 25. The single women were also more likely to die from medical conditions which indicated that they faced barriers to accessing health care. The fieldwork was conducted at the height of the Intifada and the Israeli military response, with heavy restrictions on mobility, limiting the possibility of probing deeper into the circumstances surrounding sensitive deaths. More research into the socio-cultural context of single women in Palestine society is needed as a basis for intervention.  相似文献   
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Platelet-rich fibrin (PRF) as a rich source of effective growth factors has been used as a scaffold in tissue regeneration. It is known that PRF exhibits rapid degradability against enzymes, which should be decreased using crosslinking agents to reduce the release rate of growth factors and increase the effectiveness of tissue regeneration. In this study, a carbodiimide crosslinker with different concentrations (0.01%, 0.05%, 1%, and 2%) was used to modify and improve the properties of PRF gel. The crosslinked gels were evaluated with analyses such as SEM, swelling, degradability, mechanical strength, release test, cytotoxicity, and cell adhesion. The results showed that with increasing crosslinker concentration, the morphology of the fiber structure changes drastically, the swelling rate decreases from 300% (control) to 160% for the crosslinked gel, the degradation time for the control sample increases from 8 days to more than two weeks for the crosslinked gel, and the Young''s modulus increases from 0.15 MPa (control) to 0.61 MPa for the crosslinked samples. Growth factors also showed lower release with increasing crosslinking ratio. Cytotoxicity assays demonstrated that by increasing the crosslinker concentration to 1% w/v, no cytotoxicity was observed. Cellular studies with DAPI staining showed that the cells penetrated well into the gels and were well distributed, especially in gels with lower crosslinker concentrations. In addition, the modified PRF gel can be used as a scaffold for tissue regeneration.

1-Ethyl-3-(3-dimethyl aminopropyl) carbodiimide hydrochloride (EDC) as a crosslinker can improve the physical and mechanical properties of PRF gel by forming covalent bonds.  相似文献   
85.
The hydrothermal method was used to create dilute magnetic semiconductor nanoparticles of Zn1−xCoxO (x = 0, 0.01, 0.05, 0.09). The effect of cobalt doping on the microstructure, morphological and optical properties of Zn1−xCoxO was also studied and the Co doping to host ZnO was confirmed from XRD and EDX analysis. The structural analysis showed that doping of cobalt into ZnO decreased the crystallinity, but the preferred orientation didn''t change. SEM analysis revealed that the cobalt dopant did not have a strong influence on the shape of the synthesized nanoparticles. No defect-related absorption peaks were observed in the UV-Vis spectra. The crystallinity of the doped samples was improved by high growth temperature and long growth time. Ferromagnetic behavior above room temperature was detected in co-doped ZnO nanoparticles. The ferromagnetic behavior increased with increasing Co (up to x = 0.05) doping. The ferromagnetic behavior declined when the Co content was further increased. Related research shows that doped ZnO nanoparticles have better dielectric, electrical conductivity, and magnetic properties than pure ZnO. This high ferromagnetism is usually a response reported for dilute magnetic semiconductors. These semiconductor nanoparticles were further used to designed spintronic based applications.

The enlarged central part MH loop shows for the Co = 0.09 doped ZnO sample, the ferromagnetic (FM) behavior increased, i.e., a Mr of 0.2412 emu g−1 with a Hc of 85 Oe.  相似文献   
86.
Bio-based silica, lignocellulose, and activated carbon were simply produced via the recycling of Hassawi rice biomass waste of Al-Ahsa governorate in the eastern Saudi Arabia region using a fast chemical treatment procedure. Rice husk and rice straw wastes were collected, ground, and chemically treated with sodium hydroxide to extract silica/silicate from the dried plant tissues. The liquid extract is then treated with acid solutions in order to precipitate silica/silicate at neutral medium. Lowering the pH of the supernatant to 2 resulted in the precipitation of lignocellulose. Thermal treatment of the biomass residue under N2 gas stream resulted in activated carbon production. Separated products were dried/treated and characterized using several physical examination techniques, such as FT-IR, SEM/EDX, XRD, and Raman spectroscopy in order to study their structure and morphology. Silica and lignocelluloses products were then preliminarily used in the treatment of wastewaters and water-desalination processes.  相似文献   
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BackgroundA previous European Headache Federation (EHF) guideline addressed the use of monoclonal antibodies targeting the calcitonin gene-related peptide (CGRP) pathway to prevent migraine. Since then, randomized controlled trials (RCTs) and real-world evidence have expanded the evidence and knowledge for those treatments. Therefore, the EHF panel decided to provide an updated guideline on the use of those treatments.MethodsThe guideline was developed following the Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) approach. The working group identified relevant questions, performed a systematic review and an analysis of the literature, assessed the quality of the available evidence, and wrote recommendations. Where the GRADE approach was not applicable, expert opinion was provided.ResultsWe found moderate to high quality of evidence to recommend eptinezumab, erenumab, fremanezumab, and galcanezumab in individuals with episodic and chronic migraine. For several important clinical questions, we found not enough evidence to provide evidence-based recommendations and guidance relied on experts’ opinion. Nevertheless, we provided updated suggestions regarding the long-term management of those treatments and their place with respect to the other migraine preventatives.ConclusionMonoclonal antibodies targeting the CGRP pathway are recommended for migraine prevention as they are effective and safe also in the long-term.Supplementary InformationThe online version contains supplementary material available at 10.1186/s10194-022-01431-x.  相似文献   
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