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61.
Miguel A. Reina André P. Boezaart R. Shane Tubbs Yury Zasimovich Manuel Fernández-Domínguez Paloma Fernández Xavier Sala-Blanch 《Clinical anatomy (New York, N.Y.)》2020,33(2):199-206
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
62.
Joe Iwanaga Shogo Kikuta Tsuyoshi Tanaka Yasuhiko Kamura R. Shane Tubbs 《Clinical anatomy (New York, N.Y.)》2019,32(5):672-677
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
63.
Robert M. Pohlman James L. Hinshaw Timothy J. Ziemlewicz Meghan G. Lubner Shane A. Wells Fred T. Lee Marci L. Alexander Kelly L. Wergin Tomy Varghese 《Ultrasound in medicine & biology》2021,47(8):2138-2156
Liver cancer is a leading cause of cancer-related deaths; however, primary treatment options such as surgical resection and liver transplant may not be viable for many patients. Minimally invasive image-guided microwave ablation (MWA) provides a locally effective treatment option for these patients with an impact comparable to that of surgery for both cancer-specific and overall survival. MWA efficacy is correlated with accurate image guidance; however, conventional modalities such as B-mode ultrasound and computed tomography have limitations. Alternatively, ultrasound elastography has been used to demarcate post-ablation zones, yet has limitations for pre-ablation visualization because of variability in strain contrast between cancer types. This study attempted to characterize both pre-ablation tumors and post-ablation zones using electrode displacement elastography (EDE) for 13 patients with hepatocellular carcinoma or liver metastasis. Typically, MWA ablation margins of 0.5–1.0 cm are desired, which are strongly correlated with treatment efficacy. Our results revealed an average estimated ablation margin inner quartile range of 0.54–1.21 cm with a median value of 0.84 cm. These treatment margins lie within or above the targeted ablative margin, indicating the potential to use EDE for differentiating index tumors and ablated zones during clinical ablations. We also obtained a high correlation between corresponding segmented cross-sectional areas from contrast-enhanced computed tomography, the current clinical gold standard, when compared with EDE strain images, with r2 values of 0.97 and 0.98 for pre- and post-ablation regions. 相似文献
64.
Neutrophilic urticarial dermatosis as a presenting feature of systemic juvenile idiopathic arthritis 下载免费PDF全文
Thomas Stringer BA Julia Gittler MD Shane Meehan MD Philip Kahn MD Vikash S. Oza MD 《Pediatric dermatology》2018,35(3):e170-e172
This report describes a case of chronic neutrophilic urticarial dermatosis as a presenting feature of systemic juvenile idiopathic arthritis. When encountered in children, neutrophilic urticarial dermatosis should raise suspicion of autoimmune or autoinflammatory disease. 相似文献
65.
Alcoholic cardiomyopathy (ACM) is a specific heart muscle disease found in individuals with a history of long-term heavy alcohol consumption. ACM is associated with a number of adverse histological, cellular, and structural changes within the myocardium. Several mechanisms are implicated in mediating the adverse effects of ethanol, including the generation of oxidative stress, apoptotic cell death, impaired mitochondrial bioenergetics/stress, derangements in fatty acid metabolism and transport, and accelerated protein catabolism. In this review, we discuss the evidence for such mechanisms and present the potential importance of drinking patterns, genetic susceptibility, nutritional factors, race, and sex. The purpose of this review is to provide a mechanistic paradigm for future research in the area of ACM. 相似文献
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67.
Johan A. Schmidt Matthew S. Johnson Reinhard Schinke 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(44):17691-17696
We present a first principles study of the carbon dioxide (CO2) photodissociation process in the 150- to 210-nm wavelength range, with emphasis on photolysis below the carbon monoxide + singlet channel threshold at ∼167 nm. The calculations reproduce experimental absorption cross-sections at a resolution of ∼0.5 nm without scaling the intensity. The observed structure in the 150- to 210-nm range is caused by excitation of bending motion supported by the deep wells at bent geometries in the and potential energy surfaces. Predissociation below the singlet channel threshold occurs via spin-orbit coupling to nearby repulsive triplet states. Carbon monoxide vibrational and rotational state distributions in the singlet channel as well as the triplet channel for excitation at 157 nm satisfactorily reproduce experimental data. The cross-sections of individual CO2 isotopologues (12C16O2, 12C17O16O, 12C18O16O, 13C16O2, and 13C18O16O) are calculated, demonstrating that strong isotopic fractionation will occur as a function of wavelength. The calculations provide accurate, detailed insight into CO2 photoabsorption and dissociation dynamics, and greatly extend knowledge of the temperature dependence of the cross-section to cover the range from 0 to 400 K that is useful for calculations of propagation of stellar light in planetary atmospheres. The model is also relevant for the interpretation of laboratory experiments on mass-independent isotopic fractionation. Finally, the model shows that the mass-independent fractionation observed in a series of Hg lamp experiments is not a result of hyperfine interactions making predissociation of 17O containing CO2 more efficient. 相似文献
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70.
JS Willey SA Lloyd GA Nelson TA Bateman 《Clinical reviews in bone and mineral metabolism》2011,9(1):54-62
Damage to normal, nontumor bone tissue following therapeutic irradiation increases the risk of fracture among cancer patients.
For example, women treated for various pelvic tumors have been shown to have a greater than 65% increased incidence of hip
fracture by 5 years postradiotherapy. Another practical situation in which exposure to ionizing radiation may negatively impact
skeletal integrity is during extended spaceflight missions. There is a limited understanding of how spaceflight-relevant doses
and types of radiation can influence astronaut bone health, particularly when combined with the significant effects of mechanical
unloading experienced in microgravity. Historically, negative effects on osteoblasts have been studied. Radiation exposure
has been shown to damage osteoblast precursors. Damage to local vasculature has been observed, ranging from decreased lumen
diameter to complete ablation within the irradiated volume, causing a state of hypoxia. These effects result in suppression
of bone formation and a general state of low bone turnover. More recently, however, we have demonstrated in preclinical mouse
models, a very rapid but transient increase in osteoclast activity after exposure to spaceflight and clinically relevant radiation
doses. Combined with long-term suppression of bone formation, this skeletal damage may cause long-term deficits. This review
will present a broad set of literature outlining our current set knowledge of both clinical therapy and space exploration
exposure to ionizing radiation. Additionally, we will discuss prevention of the initial osteoclast-mediated bone loss, the
need to promote normal bone turnover and long-term quality of bone tissue, and our hypothesized molecular mechanisms. 相似文献