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排序方式: 共有1610条查询结果,搜索用时 31 毫秒
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The estrogen of the doum palm kernel and pollen grains has been isolated as the p,p′-nitrophenylazo benzoyl derivative and identified as estrone. 相似文献
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The objective of this study is to compare the thermal stress changes in the tooth microstructures and the hydrodynamic changes of the dental fluid under hot and cold stimuli. The dimension of the microstructures of eleven cats’ teeth was measured by scanning electron microscopy, and the changes in thermal stress during cold and hot stimulation were calculated by 3D fluid–structure interaction modeling. Evaluation of results, following data validation, indicated that the maximum velocities in cold and hot stimuli were ??410.2?±?17.6 and +?205.1?±?8.7 µm/s, respectively. The corresponding data for maximum thermal stress were ??20.27?±?0.79 and +?10.13?±?0.24 cmHg, respectively. The thermal stress caused by cold stimulus could influence almost 2.9 times faster than that caused by hot stimulus, and the durability of the thermal stress caused by hot stimulus was 71% greater than that by cold stimulus under similar conditions. The maximum stress was on the tip of the odontoblast, while the stress in lateral walls of the odontoblast and terminal fibril was very weak. There is hence a higher possibility of pain transmission with activation of stress-sensitive ion channels at the tip of the odontoblast. The maximum thermal stress resulted from the cold stimulus is double that produced by the hot stimulus. There is a higher possibility of pain transmission in the lateral walls of the odontoblast and terminal fibril by releasing mediators during the cold stimulation than the hot stimulation. These two reasons can be associated with a greater pain sensation due to intake of cold liquids. 相似文献
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The objective of this investigation was to evaluate the effect of delivery strategies such as cyclodextrin complexation and
liposomes on the topical delivery of ketorolac acid (KTRA) and ketorolac tromethamine. Ketorolac acid–hydroxypropyl-β-cyclodextrin
solid dispersions (KTRA-CD) were prepared by kneading method. The liposomes containing ketorolac tromethamine (KTRM) and KTRA-CD
were prepared. The in vitro permeation of KTRM solution, KTRA solution, KTRA-CD, and liposomes containing KTRM or KTRA-CD through guinea pig skin was
evaluated. The anti-inflammatory activity of the topically applied KTRA-CD gel (containing 1% w/w KTRA) was compared to that of orally delivered KTRM solution. The KTRA-CD demonstrated significantly higher transdermal transport
of ketorolac as compared to all other systems whereas liposomes significantly reduced the transport of ketorolac. The anti-inflammatory
activity of the topically applied KTRA-CD gel was similar to that of the orally administered KTRM. Thus, cyclodextrin complexation
enabled effective transdermal delivery of the ketorolac. 相似文献
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Plasmonics - We study two-dimensional (2D) hole arrays drilled into a perfect conductor slab covered with a graphene sheet. Such arrays support the extraordinary transmission of electromagnetic... 相似文献
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Ensieh Sajadi Sara Dadras Mohammad Bayat Shabnam Abdi Hamid Nazarian Sanaz Ziaeipour Fatemeh Mazini Mahsa Kazemi Mohammad Bagheri Aida Valizadeh Mohammad-Amin Abdollahifar 《Journal of cellular biochemistry》2019,120(10):17312-17325
The current study was conducted to assess the relationship between testicular cells in spermatogenesis, through which the production of healthy and mature sperm is essential. However, it seems necessary to obtain more information about the three-dimensional pattern of the testis cells arrangement, which is directly related to the function of the testis after induction of diabetes. Twelve adult mice (28-30 g) were assigned into two experimental groups: (1) control and (2) diabetic (40 mg/kg STZ). The epididymal sperm collected from the tail of the epididymis and testes samples were taken for stereology, immunocytochemistry and RNA extraction. Our data showed that diabetes could notably decrease the number of testicular cells, together with a reduction of total sperm count. In addition, the results from the second-order stereology indicated the significant changes in the spatial arrangement of Sertoli cells and spermatogonial cells in the diabetic groups, in comparison with the control (P < .05). Moreover, the immunohistochemistry results showed a significant reduction in Sex-determining Region Y (SRY) box 9 gene (SOX9), vimentin, occludin, and connexin-43 positive cells in the diabetic groups compared with the control (P < .05). Furthermore, our data showed that the expression of steroidogenic acute regulatory protein steroidogenic acute regulatory protein (StAR) and peripheral benzodiazepine receptor peripheral benzodiazepine receptor (PBR) was significantly reduced in the diabetic groups, in comparison with the control (P < .05). These findings suggest that structural and functional changes of testis cells after induction of diabetes cause the alterations in the spatial arrangement of Sertoli and spermatogonial cells, ultimately influencing the normal spermatogenesis in mice. 相似文献
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Jaydari Amin Esmaeili Fard Barzegar Peyman Forouharmehr Ali Kakanezhadifard Ali Nazifi Narges 《International journal of peptide research and therapeutics》2019,25(3):1127-1133
International Journal of Peptide Research and Therapeutics - Query fever is an important disease caused by Coxiella burnetii, therefore vaccination against this disease is so crucial. Com1 is one... 相似文献
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Marzie Mohammadpour M. Amin Jalali J. P. Michaud Mahdi Ziaaddini Hamid Hashemirad 《BioControl》2014,59(3):279-286
Females of Trissolcus agriope (Platygastridae) avoid host (Brachynema signatum) eggs parasitized by conspecifics or Ooencyrtus pityocampae (Encyrtidae), but females of the latter species will superparasitize and multiparasitize, although they mostly attack unparasitized eggs. Females of T. agriope were more efficient in the laboratory and parasitized more hosts in 24 and 48 h. In multiparasitized hosts, O. pityocampae was a superior larval competitor and could complete also development as a facultative hyperparasitoid. When females of both species foraged together, T. agriope parasitized significantly more than O. pityocampae, about 50 % in both cases, although O. pityocampae almost doubled its parasitism rate as the exposure period was lengthened from 24 to 48 h. When O. pityocampae followed T. agriope in sequential foraging bouts, the former species successfully parasitized more hosts than the latter. The advisability of co-releases of both species to improve biological control of first generation B. signatum in Iranian pistachio orchards is discussed. 相似文献