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排序方式: 共有154条查询结果,搜索用时 31 毫秒
71.
The effects of anethol, the major component of anise oil, on the Ca2+-dependent excitability and afterhyperpolarization (AHP) in snail neurons were examined using intracellular recording. Anethol (0.5%) significantly broadened the spike, reduced the firing frequency and enhanced the AHP amplitude. In contrast, anethol (2%) significantly increased the firing frequency and decreased the AHP. Blockade of Ca2+ channels after anethol application depolarized the membrane potential and significantly reduced the firing rate. Furthermore, in the presence of anethol (0.5%) a significant decrease in the AHP was observed by Ca2+ channels blockage. Here, anethol-induced functional modification of Ca2+ and Ca2+-activated K+ channels is suggested. 相似文献
72.
Javad Sadeghinezhad Zahra Ganji Sirous Sadeghian Chaleshtori Hadis Bojarzadeh Mahdi Aghabalazadeh Asl Ali Bayat Khomejini Ehsan Roominai Mohsen Hosseini Margherita De Silva 《Anatomia, histologia, embryologia》2021,50(6):1026-1033
Sheep have been used as translational models of human postnatal testicular development. However, the morphometric features of the normal developing testis in sheep embryos have not been previously investigated using stereology. The objective of the present work was to establish normal quantitative parameters for fetal testicular tissue components in sheep, using unbiased design-based stereological methods. Twenty-four sheep embryos were divided into four gestational age groups (9–11, 12–14, 15–17 and 18–20 weeks of gestation) on the basis of the embryos’ crown-rump length. Isotropic, systematic uniform random sections of the left testes were obtained by employing the orientator method. Testicular total volume, the absolute and proportional volumes occupied by the seminiferous tubules and interstitial tissue, as well as the seminiferous tubule length, were estimated using the point-counting system and the unbiased counting frame principle. All the parameters, with the exception of the interstitial tissue's fractional volume, gradually increased along with gestational age, with the maximum increase especially seen in the late fetal stages. The proportional volume of the interstitial tissue, on the other hand, showed a decreasing trend along with increasing gestational age. The absolute volume of the testes, of the seminiferous tubules and of the interstitial tissue, and the length of the seminiferous tubules showed a significant (p< 0.05) positive linear correlation with gestational age. Several similarities were observed with human testicular embryogenesis. The stereological data emerging from the present study might prove useful as basic contribution to the fields of andrology and embryology and stimulate further research in these areas. 相似文献
73.
A rapid, selective, and accurate quantitative 31P nuclear magnetic resonance (31P NMR) spectroscopy method was used for the chiral recognition of the racemic organophosphorus pesticide fenamiphos using chiral solvating agents (CSAs). Six neutral cyclodextrins (CDs) (α-CD, β-CD, methyl-β-CD, hydroxyethyl-β-CD, hydroxypropyl-β-CD, and hydroxypropyl-γ-CD) and two anionic CDs (carboxymethyl-β-CD and carboxyethyl-β-CD) were selected for these experiments. The shift displacement values (Δδ), after addition of each of the eight CDs in the highest possible molar ratio to a guest, were recorded. The results showed that β-CD and hydroxypropyl-β-CD were the best chiral solvating agents for the enantiomeric discrimination of fenamiphos. Two-dimension rotating frame nuclear Overhauser spectroscopy (ROESY) was used to investigate the structure of the β-CD-fenamiphos inclusion complex in aqueous solution. To determine the fenamiphos enantiomers, a calibration curve was drawn for two enantiomers over the range of 0.05-0.25 mg mL?1. The limits of detection (S/N = 3) were obtained as 0.0068 and 0.0060 mg mL?1 for fenamiphos enantiomers. The recovery studies were performed on aqueous real samples ranging from 94 to 107% with coefficients of variation of ≤ 9%. 相似文献
74.
Zahra Davoudi Nathan Peroutka-Bigus Bryan Bellaire Albert Jergens Michael Wannemuehler Qun Wang 《Marine drugs》2021,19(5)
Intestinal organoids can be used as an ex vivo epithelial model to study different drug delivery effects on epithelial cells’ luminal surface. In this study, the impact of surface charge on the delivery of 5-ASA loaded PLGA nanoparticles into the lumen of organoids was investigated. Alginate and chitosan were used to coat the nanoparticles and provide negative and positive charges on the particles, respectively. The organoid growth and viability were not affected by the presence of either alginate- or chitosan-coated nanoparticles. It was shown that nanoparticles could be transported from the serosal side of the organoids to the lumen as the dye gradually accumulated in the lumen by day 2–3 after adding the nanoparticles to the Matrigel. By day 5, the dye was eliminated from the lumen of the organoids. It was concluded that the positively charged nanoparticles were more readily transported across the epithelium into the lumen. It may be attributed to the affinity of epithelial cells to the positive charge. Thus, the organoid can be utilized as an appropriate model to mimic the functions of the intestinal epithelium and can be used as a model to evaluate the benefits of nanoparticle-based drug delivery. 相似文献
75.
Zahra Abbasi Maryam Golabadi Samar Khayamim Mohammad Pessarakli 《Journal of plant nutrition》2013,36(20):2660-2672
AbstractThirty-four sugar beet drought-tolerant half-sib families were screened in greenhouse experiment under saline (16?dSm?1) and normal conditions, and a subset of 10 tolerant genotypes were selected for evaluating of yield-related traits, Na+, K+, and α-amino-N nitrogen contents under saline field condition (12?dSm?1). Drought-tolerant genotypes showed a different tolerance level under salt stress. Significant correlation was observed between EP2s and STIEP2 in greenhouse with root yield (RY) in saline field condition. It should be possible that a simple measurement at 16?dSm?1 in the greenhouse can be used as main part of sugar beet salt-tolerant breeding program. In total, genotypes SBSI-DR I-HSF14-P.23 (# 16) and 436B-HSF9-P.27 (# 26) were recognized as salt- and drought-tolerant genotypes with low Na+ and K+ contents in root and high white sugar content (WSC) and RY in field. A larger panel of genotypes to validate this kind of association is necessary. 相似文献
76.
77.
Zahra Gorzin Ali Akbar Gorzin Alijan Tabarraei Naser Behnampour Shiva Irani Amir Ghaemi 《Iranian Biomedical Journal》2014,18(1):1-7
Backgrounds: Most of the hepatitis C virus (HCV) infections elicit poor immune responses and 75% to 85% of cases become chronic; therefore, the development of an effective vaccine against HCV is of paramount importance. In this study, we aimed to evaluate co-administration of HCV non-Structural Protein 2 and IL-12 DNA vaccines in C57BL/6 mice. Methods: A plasmid encoding full-length HCV NS2 protein (non-structural protein 2) was generated and used to vaccinate mice. Negative control (an empty expression vector) was also employed to evaluate the background response. To investigate immune responses against vaccine, C57BL/6 mice received three doses of the vaccine with a two-week interval. Cellular immunity was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay for lymphocyte proliferation, lactate dehydrogenase release for cytotoxic T lymphocyte (CTL) activity and cytokine assay. Results: The findings demonstrated that immunization of mice with plasmid expressing HCV NS2 induced CTL response, interferon gamma production, and lymphocyte proliferation compared to negative control. The results also demonstrated that co-administration of IL-12 with the HCV NS2 plasmid induced significantly better immune response in C57BL/6 mice. Conclusion: DNA vaccine encoding HCV NS2 is an effective candidate that can trigger CTL-based immune response against HCV. In addition, the results suggested that combining the DNA vaccine approach with immune stimulatory cytokines may significantly enhance antigen-specific immune responses. Key Words: Hepatitis C virus (HCV), NS2 protein, DNA vaccine, IL-12 相似文献
78.
Mohammad Taghi Mohammadi Reza Amini Zahra Jahanbakhsh Shahnaz Shekarforoush 《Iranian Biomedical Journal》2013,17(3):152-157
Background: It is well known that the development of brain oxidative stress is one of the most serious complications of arterial hypertension that evokes brain tissue damage. The aim of this study was to examine the effects of atorvastatin treatment (20 mg/kg/day), as an antioxidant, to prevent the brain tissue oxidative stress in the hypertensive (HTN) rats. Methods: Experiments were performed in four groups of rats (n = 5 each group): sham, sham-treated, HTN and HTN treated. Rats were made HTN by aortic constriction above the renal arteries. After 30 days, rats were slaughtered under deep anesthesia to remove brain hemispheres. After tissue homogenization, enzyme activities of superoxide dismutase (SOD) and catalase (CAT), as well as glutathione (GSH) content and malondialdehyde (MDA) level were determined by biochemical methods. Results: In HTN rats, arterial blood pressure was increased about 40% and brain enzyme activities of SOD and CAT were significantly decreased compared with sham group. Induction of hypertension significantly decreased GSH content and increased MDA level of brain tissue. Treatment with atorvastatin enhanced the activity of SOD and prevented from GSH decrement during hypertension. Conclusion: Based on the findings of this study, treatment with atorvastatin might have saved the brain tissue of HTN rats from hypertension-induced oxidative stress. Key Words: Atorvastatin, Aortic coarctation, Oxidative stress, Hypertension 相似文献
79.
Mohammad Hashemi Zahra Zakeri Ebrahim Eskandari-Nasab Mahdi Atabaki Seyed Mohammad Ebrahim Pourhosseini Mehdi Jahantigh Gholamreza Bahari Mohsen Taheri 《Iranian Biomedical Journal》2013,17(4):194-199
Background: Rheumatoid arthritis (RA) is a chronic inflammatory disease with many genetic factors predisposing to disease susceptibility. The aim of the present study was to investigate the impact of CD226 rs727088 and rs763361 polymorphisms and susceptibility to RA in a sample of the Iranian population. Methods: This case-control study was carried out on 100 patients with RA and 104 healthy subjects. The polymorphisms were determined using tetra amplification refractory mutation system-polymerase chain reaction assay. Results: The rs763361 (Gly307Ser) polymorphism increased the risk of RA in codominant, dominant and recessive-tested inheritance models (odds ratio [OR] = 3.18, 95% confidence intervals [95% CI] = 1.44-7.02, P = 0.004, CC vs. TT, and OR = 1.98, 95% CI = 1.10-3.57, P = 0.023, CC vs. CT-TT, and OR = 2.61, 95% CI = 1.26-5.37, P = 0.010, CC + CT vs. TT, respectively). In addition, the rs763361 T allele increased the risk of RA (OR = 2.06, 95% CI = 1.38-3.08, P<0.001). However, no significant difference was observed among the groups regarding CD226 rs727088 polymorphism (χ2 = 3.20, P = 0.202). Conclusions: Our finding showed that CD226 rs763361, but not rs727088, gene polymorphism increased the risk of RA in a sample of the Iranian population.Key Words: Rheumatoid arthritis (RA), CD226, Polymorphism 相似文献
80.
Fereidoon Nour-Mohammadzadeh Zahra Baradaran Seyed Saeed Hesaraki Zahra Yadegari Naser Alidadi Saeed Sattari Tabrizi 《Tropical animal health and production》2010,42(8):1601-1604
A 1-week old, two-humped female camel (Camelus bactrianus) calf with continual whining, epiphora, anorexia, muscle twitching, and lateral recumbency was referred to a veterinary hospital.
Although she died shortly after preliminary clinical examination, but necropsy was performed and tissue samples were taken
for further microbiological and pathological examinations. On bacteriological investigation, Salmonella typhimurium and Streptococcus agalactiae were isolated. Histopathologically, lesions consisted of hyperemia and hemorrhage in all serosal and mucosal surfaces, gastroenteritis,
and purulent ascites, associated with suppurative omphalitis. Acute nutmeg liver demonstrated centrilobular congestion and
moderate fatty changes without any inflammatory cell infiltration. The abomasal and intestinal mucosa were hemorrhagic and
erosive. The brain was hyperemic with severe fibrinopurulent meningoencephalitis. Except for dromedary camels and llamas,
there has been no previous report of an acute, fatal septicemia in a two-humped camel calf due to S. typhimurium accompanied by S. agalactiae. 相似文献