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51.
the mechanistic target of rapamycin(m tor) is an intracellular protein kinase that functions as an energy and nutrient sensor in the cellular microenvironment of neurons. modulation of m tor is vital when nutrient and energy sources become limited. hypoxia, traumatic brain injury, cellular energy states, and growth factors all regulate the phosphorylation and total levels of m tor in cells. alterations in the microenvironment induce transduction of signals to downstream proteins by m tor allowing for cells to make the necessary adjustments to counteract stressors and survive. progesterone, a hydrophobic steroid hormone, has been shown in studies of non-neural tissue to be a suppressor of m tor and modulator of m tor phosphorylation. our study tested the effects of progesterone on m tor expression following traumatic brain injury. c57 bl/6 mice were treated with progesterone(8 mg/kg) at 1(intraperitoneal), 6(subcutaneous), 24(subcutaneous), and 48(subcutaneous) hours post closed skull traumatic brain injury. the hippocampus was then harvested 72 hours post injury and prepared for western blot analysis. we found that progesterone significantly decreased total m tor levels in all groups compared to sham treated with vehicle. this was further confirmed by immunostaining showing decreased cytoplasmic m tor levels compared to sham. our study shows progesterone is a significant modulator of m tor levels in the hippocampus of mice following traumatic brain injury.  相似文献   
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Across the globe, pharmacists on the frontline continue to fight COVID-19 and its continuously evolving physical, mental, and economic consequences armed by their knowledge, professionalism, and dedication. Their need for credible scientific evidence to inform their practice has never been more urgent. Despite the exponentially increasing number of publications since the start of the pandemic, questions remain unanswered, and more are created, than have been resolved by the increasing number of publications.A panel of leading journal editors was convened by the International Pharmaceutical Federation (FIP) Pharmacy Practice Research Special Interest Group to discuss the current status of COVID-19 related research, provide their recommendations, and identify focal points for pharmacy practice, social pharmacy, and education research moving forward.Key priorities identified spanned a wide range of topics, reflecting the need for good quality research to inform practice and education. The panel insisted that a foundation in theory and use of rigorous methods should continue forming the basis of inquiry and its resultant papers, regardless of topic area. From assessing the clinical and cost effectiveness of COVID-19 therapies and vaccines to assessing different models of pharmaceutical services and education delivery, these priorities will ensure that our practice is informed by the best quality scientific evidence at this very challenging time.  相似文献   
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The use of social media opens content to the general public and, as a result, places images of cadaveric dissection in an open forum. This raises the question: should the general public have access to such material? A survey was conducted examining whether the general public should have access to gross cadaveric dissection images and videos for educational purposes via social media. Both medical and laypersons were queried. Questions included in the survey considered whether images were too graphic, whether online cadaveric content should be age‐restricted, and whether consent by the deceased was necessary. A link to the survey was accessible to 63,562 followers through the Seattle Science Foundation's Facebookpage for 3 weeks. Among 300 responders, 89% (267/300) agreed that portrayals of cadaveric specimens/dissection on social media should be accessible by the general public for anatomical education, and 84.67% (254/300) stated that cadaveric dissection is not too graphic for untrained eyes. There was agreement by 60.33% (181/300) that an age restriction should be in place for the viewing of cadaveric dissection on social media, and 39.33% (253/300) of responders suggested restriction to 18 years and older. No statistically significant association was noted between a prior or current history of anatomy education and the frequency of positive responses to the survey questions. Social media is an innovative tool for dispensing anatomical education. The use of cadaveric images and videos provides accessibility to the general public who wish to learn more about human anatomy and their own body. Clin. Anat. 32:1033–1041, 2019. © 2019 Wiley Periodicals, Inc.  相似文献   
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The epineurium has been accepted as the outer anatomical barrier of the peripheral nerves. Our objective was to characterize the microanatomy of the layers surrounding nerves using different tissue-specific staining methods. Two hundred forty-two cross sections of human sciatic and median nerves, and brachial plexuses of eight fresh unembalmed cadavers, were examined. The samples were fixed in formaldehyde solution and stained with hematoxylin–eosin, Masson's trichrome, or epithelial membrane antigen under standard conditions. Because epithelial membrane antigen only stains the perineurium, we demonstrated using hematoxylin–eosin and Masson's trichrome that there were different collagen layers inside and outside the nerves. All fascicles had a collagen layer that surrounded the perineurium and were in close contact with it, with no adipose tissue between them. Unlike the perineurium, this layer, an “internal epineurium,” contained no cells, and it surrounded one or a small group of fascicles. Bundling these fascicles or small groups of fascicles together was the true epineurium, and between the true and internal epineurium, we consistently found an adipose-containing compartment. More proximal to this, the tibial and common peroneal nerves were bundled together by another collagen layer, the circumneurium, which also had a fat-cell-containing compartment deep to it. There were scattered collagen fibers among the adipocytes. Using tissue-specific staining, we were able to demonstrate a collagen layer, the “internal epineurium.” Outside the nerves, we identified several fat-containing concentric compartments. Those compartments were limited by collagen fiber layers that were also similar to the epineurium. Clin. Anat. 33:199–206, 2020. © 2019 Wiley Periodicals, Inc.  相似文献   
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Most of the studies of the mandible's anatomical variations have presented the authors' speculations, and only a limited number has provided evidence that demonstrated the actual complications injury to the variant structures caused. To our knowledge, no study has evaluated the risks associated with these variant anatomical structures' injury. We reviewed articles that described clinical cases of the injury to, and anatomical studies of, three anatomical variants of the mandible—the accessory mental, lingual, and retromolar foramina—with which dentists are relatively familiar and that are mentioned often in the context of implant and third molar surgeries, to describe risk assessment methods with which to evaluate potential complications preoperatively. Only a limited number of the clinical reports of injury to the mandible's accessory foramina were available. The potential severe complication of injury of the accessory mental foramen (AMF) is sensory disturbance of the lower lip. Risk of neurosensory disturbance of lower lip can be assessed by AMF/MF ratio and positional relations to the MF. Potential severe complication of injury of the lingual foramen is bleeding and hemorrhage in the oral cavity's floor. Risk of bleeding can be assessed by diameter and positional relation between the mental spine/mylohyoid line. A risk assessment of the retromolar foramen could not be made because of inadequate data. We hope the risk assessments suggested will encourage dentists to predict intraoperative/postoperative complications caused by damaging the mandible's accessory foramina. Clin. Anat. 32:672–677, 2019. © 2019 Wiley Periodicals, Inc.  相似文献   
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