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排序方式: 共有3678条查询结果,搜索用时 15 毫秒
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Tayyaba Ali Muhammad Ismail Farkhanda Asad Asma Ashraf Usman Waheed Qaiser M. Khan 《Drug and chemical toxicology》2018,41(2):213-220
To control agricultural pests and meet the increasing food demands, pesticides use has been increased substantially over time. Although pesticides are relatively specific to their targets, they can affect non-target organisms and are hazardous for the population around the application areas particularly to the individuals engaged in different types of agricultural activities. This situation is worse in developing and under-developed countries where personal protective equipment is merely used and regulatory guidelines are hardly practiced. In the present study, DNA damage in women exposed to pesticides while picking cotton with bare hands was assessed using single cell gel electrophoresis assay or comet assay. The presence of pesticides in blood serum of exposed individuals was also analyzed using high-performance liquid chromatography. Blood samples were collected from 138 (69 exposed and 69 control) randomly selected females from a major cotton growing area (Bahawalpur District) of the Punjab province of Pakistan. DNA damage, as determined by the mean comet tail length, was significantly higher (p?0.001) in the exposed group compared to the unexposed. A positive correlation of DNA damage with age and exposure time was also observed. Residues of three pesticides, cyhalothrin, endosulfan, and deltamethrin found significantly higher (p?0.001) in the serum samples of the exposed group compared to the unexposed. It was observed that the groups with higher mean comet tail length also had a higher concentration of pesticides in their serum samples indicating a positive association of DNA damage and pesticide exposure. The present study suggests that exposure to pesticides leads to DNA damage. 相似文献
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Amina Cheboub Nadia Regouat Reda Djidjik Assia Slimani Fatima Hadj-Bekkouche 《Acta histochemica》2019,121(8):151441
PurposeThis study aimed to evaluate the effects of estrogen reduction on amyloid deposition, some lipid metabolism and oxidative stress markers, PSA-like production and p63 expression in the prostate of the adult rat.MethodsAromatase inhibitor: Formestane (4-OHA), was administrated to male rats, at a dose of 0.1 mg/kg b.w./day, for 10 days. The control group (CONT) received the same volume of placebo injection (NaCl 0.9%).Results4-OHA treatment induced a significant accumulation of intraprostatic cholesterol (138.90 ± 17.64 vs 85.12 ± 2.87, p = 0.01); against an insignificant diminution of malondialdehyde (412.6 ± 54.35 vs 842.70 ± 336.50, p > 0.05) and glutathione (2.40 ± 0.23 vs 3.65 ± 0.88, p > 0.05). This was associated with a significant decrease of nitric oxide (31.76 ± 7.07 vs 179.40 ± 58.35, p = 0.024). Additionally, 4-OHA significantly increased the intraprostatic production of PSA-like (11.12 ± 2.78 vs 3.91 ± 0.43, p = 0.043). The prostatic histology revealed an amyloid deposition, in all prostatic lobes and a smooth muscle layer growth (p < 0.05); especially significant in the dorsal and lateral lobes. Theses lobes manifested a basal cells proliferation, with a 3-fold increase of p63 expression (p < 0.001). The ventral lobe presented epithelial atrophy (37.80 ± 16.20 vs 167.60 ± 5.16, p < 0.05); with occasional and significant proliferative foci (247.00 ± 9.573 vs 167.60 ± 5.16 p < 0.05).Discussion and conclusionAromatase inhibition, in the adult male rat, alters the prostatic function by reducing nitric oxide availability and inducing amyloid deposition along with limiting the differentiation of basal cells, through a lobe-specific p63-overexpression. 相似文献
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Loay Salman Hector Castro Roberto I. Vazquez‐Padron Mauricio Monrroy Yehia Abdelwahed Abid Rizvi Juan Duque Muhammad Usman Talha Akmal Donna Merrill Ali Nayer Arif Asif 《Seminars in dialysis》2014,27(2):E21-E23
Percutaneous transluminal balloon angioplasty (PTA) is a commonly performed procedure for hemodialysis vascular access dysfunction including thrombosis. While PTA is generally safe, balloon rupture during the procedure is a potential complication. Because such a rupture can cause damage to the blood vessel, indication of an imminent balloon rupture might help avoid such a complication. This analysis reports on six PTA procedures that were complicated by balloon rupture. All cases demonstrated terminal (caudal/cranial) cinch deformation. There was a loss of sharp terminal tapering and its replacement with banana silhouette before the balloon rupture. Importantly, the contour deformation and balloon rupture occurred at a pressure that was lower than the rated burst pressure. The cinch deformity can be used as an indication for impending balloon rupture. We suggest deflation of balloons that demonstrate shape deformations to avoid vascular injury. 相似文献
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Janey S.A. Pratt Allen Browne Nancy T. Browne Matias Bruzoni Megan Cohen Ashish Desai Thomas Inge Bradley C. Linden Samer G. Mattar Marc Michalsky David Podkameni Kirk W. Reichard Fatima Cody Stanford Meg H. Zeller Jeffrey Zitsman 《Surgery for obesity and related diseases》2018,14(7):882-901
The American Society for Metabolic and Bariatric Surgery Pediatric Committee updated their evidence-based guidelines published in 2012, performing a comprehensive literature search (2009–2017) with 1387 articles and other supporting evidence through February 2018. The significant increase in data supporting the use of metabolic and bariatric surgery (MBS) in adolescents since 2012 strengthens these guidelines from prior reports. Obesity is recognized as a disease; treatment of severe obesity requires a life-long multidisciplinary approach with combinations of lifestyle changes, nutrition, medications, and MBS. We recommend using modern definitions of severe obesity in children with the Centers for Disease Control and Prevention age- and sex-matched growth charts defining class II obesity as 120% of the 95th percentile and class III obesity as 140% of the 95th percentile. Adolescents with class II obesity and a co-morbidity (listed in the guidelines), or with class III obesity should be considered for MBS. Adolescents with cognitive disabilities, a history of mental illness or eating disorders that are treated, immature bone growth, or low Tanner stage should not be denied treatment. MBS is safe and effective in adolescents; given the higher risk of adult obesity that develops in childhood, MBS should not be withheld from adolescents when severe co-morbidities, such as depressed health-related quality of life score, type 2 diabetes, obstructive sleep apnea, and nonalcoholic steatohepatitis exist. Early intervention can reduce the risk of persistent obesity as well as end organ damage from long standing co-morbidities. 相似文献
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Faheem Ullah Fatima Javed M. B. H. Othman Abbas Khan Rukhsana Gul Zulkifli Ahmad 《Journal of biomaterials science. Polymer edition》2018,29(4):376-396
Addressing the functional biomaterials as next-generation therapeutics, chitosan and alginic acid were copolymerized in the form of chemically crosslinked interpenetrating networks (IPNs). The native hydrogel was functionalized via carbodiimide (EDC), catalyzed coupling of soft ligand (1,2-Ethylenediamine) and hard ligand (4-aminophenol) to replace –OH groups in alginic acid units for extended hydrogel- interfaces with the aqueous and sparingly soluble drug solutions. The chemical structure, Lower solution critical temperature (LCST ≈ 37.88 °C), particle size (Zh,app ≈ 150–200 nm), grain size (160–360 nm), surface roughness (85–250 nm), conductivity (37–74 mv) and zeta potential (16–32 mv) of native and functionalized hydrogel were investigated by using FT-IR, solid state-13C-NMR, TGA, DSC, FESEM, AFM and dynamic light scattering (DLS) measurements. The effective swelling, drug loading (47–78%) and drug release (53–86%) profiles were adjusted based on selective functionalization of hydrophobic IPNs due to electrostatic complexation and extended interactions of hydrophilic ligands with the aqueous and drug solutions. Drug release from the hydrogel matrices with diffusion coefficient n ≈ 0.7 was established by Non- Fickian diffusion mechanism. In vitro degradation trials of the hydrogel with a 20% loss of wet mass in simulated gastric fluid (SGF) and 38% loss of wet mass in simulated intestinal fluid (SIF), were investigated for 400 h through bulk erosion. Consequently, a slower rate of drug loading and release was observed for native hydrogel, due to stronger H-bonding, interlocking and entanglement within the IPNs, which was finely tuned and extended by the induced hydrophilic and functional ligands. In the light of induced hydrophilicity, such functional hydrogel could be highly attractive for extended release of sparingly soluble drugs. 相似文献