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991.
L S Dure th A B Young J B Penney Jr 《Proceedings of the National Academy of Sciences of the United States of America》1992,89(16):7688-7692
Division of the mammalian neostriatum into two intermingled compartments called striosomes and matrix has been established by analysis of enzyme activity, neuropeptide distribution, nucleic acid hybridization, and neurotransmitter receptor binding. Striosomes and matrix are distinct with respect to afferent and efferent connections, and these regions provide the potential for modulation and integration of information flow within basal ganglia circuitry. The primary neurotransmitters of corticostriatal afferents are excitatory amino acids, but to date no correlation of excitatory amino acid receptors and striatal compartments has been described. We examined binding to the three pharmacologically distinct ionotropic excitatory amino acid receptors, N-methyl-D-aspartate, alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid, and kainate, in human striatum using in vitro receptor autoradiography and compared the binding to striosomes and matrix histochemically defined by acetylcholinesterase activity. Our findings reveal increased binding to N-methyl-D-aspartate receptors and alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptors in matrix relative to striosomes and increased kainate receptor binding in striosomes relative to matrix. These results suggest that afferent input to the two striatal compartments may be mediated by pharmacologically distinct excitatory amino acid receptor subtypes. 相似文献
992.
R N Johnson D G Young J F Butler H Bogaert-Diaz 《The American journal of tropical medicine and hygiene》1992,46(3):282-287
Two species of sand flies were collected by various methods from sites in the Dominican Republic. Lutzomyia cayennensis hispaniolae was the more common of the two. It was found in wooded habitats from sea level to an elevation of 442 m. This species was observed feeding on lizards (Anolis sp.) in the wild. In the laboratory, it fed only on lizards and only under lighted conditions. The other species, Lu. christophei was only found in the vicinity of seven leishmaniasis case sites. It readily fed on or probed rodents and humans. Although no naturally infected sand flies were collected, in the laboratory Lu. christophei was readily capable of transmitting the Dominican Leishmania parasite to uninfected BALB/c mice. We collected 167 specimens of three species of rodents and three Herpestes auropunctatus (mongoose) from the vicinity of two case sites. All four species are non-endemics introduced in post-Columbian times. Although we were unable to isolate parasites from any of these specimens, four of 44 Rattus rattus from one case site were seropositive for antibodies against Leishmania by indirect fluorescent antibody testing. This represents the first report of transmission of the Dominican Leishmania parasite by a sympatric species of sand fly and suggests that commensal rodents may play a role in the epidemiologic cycle. 相似文献
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994.
995.
Ovarian microcystic stromal tumor: A novel extracolonic tumor in familial adenomatous polyposis 下载免费PDF全文
Sang Hun Lee Young Wha Koh Hyun Jin Roh Hee Jeong Cha Yong‐Soon Kwon 《Genes, chromosomes & cancer》2015,54(6):353-360
Ovarian microcystic stromal tumor (MCST) is a very rare neoplasm; hence, its nomenclature was recently designated as “Distinctive morphologic and immunohistochemical features” in 2009. Its exact origin, etiological genetic alterations, and background are not yet clearly known. Familial adenomatous polyposis (FAP) is an autosomal dominant disease that leads to development of colorectal polyps via germ‐line mutations of the APC gene on chromosome 5q21~22. In this study, we report a 40‐year‐old female patient who had ovarian MCST and FAP. On sequencing the APC gene in ovarian MSCT, we detected a novel somatic mutation of the APC gene in exon 11, with a heterozygous deletion at nucleotide position c.1540delG (p.Ala514 Profs*9). Mutations of β‐catenin (CTNNB1) and FOXL2 were not detected. Although one case demonstrating involvement of Wnt/β‐catenin in ovarian MCST associated with FAP has been presented previously, no detailed information was provided. Thus, this is the ovarian MCST with a somatic mutation of APC in a patient with FAP. © 2015 Wiley Periodicals, Inc. 相似文献
996.
997.
The clear cell/lipid‐rich change has been described in neuroendocine tumors in several organs, but rarely observed in the appendix. In this study, we describe the morphologic, immunohistochemical features of incidentally discovered appendiceal carcinoids entirely represented by clear cells in a 22‐year‐old man and a 52‐year‐old woman. Ultrastructual examination demonstrated abundant lipid droplets and dense core granules. The mechanism leading to lipid accumulation in the cytoplasm has not been discovered, but degenerative processes following recurrent inflammatory change might be considered. This uncommon variant of appendiceal classic carcinoid tumors may bear a superficial resemblance to goblet carcinoid and/or appendiceal metastases from clear cell carcinoma. Awareness of clear cell carcinoid of the appendix will prevent incorrect diagnosis and unnecessary aggressive management. 相似文献
998.
Ling Li Wenjun Wang Yu Pan Yuhan Zhu Xiaoguang Liu Hyeon Mi Noh Byung Kee Moon Byung Chun Choi Jung Hyun Jeong 《RSC advances》2018,8(3):1191
The vanadate-based phosphors Sr2V2O7:Eu3+ (SV:Eu3+), Sr9Gd(VO4)7:Eu3+ (SGV:Eu3+) and Sr9Gd(VO4)7/Sr2V2O7:Eu3+ (SGV/SV:Eu3+) were obtained by solid-state reaction. The bond-energy method was used to investigate the site occupancy preference of Eu3+ based on the bond valence model. By comparing the change of bond energy when the Eu3+ ions are incorporated into the different Sr, V or Gd sites, we observed that Eu3+ doped in SV, SGV or SV/SGV would preferentially occupy the smaller energy variation sites, i.e., Sr4, Gd and Gd sites, respectively. The crystal structures of SGV and SV, the photoluminescence properties of SGV:Eu3+, SV, SGV/SV and SGV/SV:Eu, as well as their possible energy transfer mechanisms are proposed. Interesting tunable colours (including warm-white emission) of SGV/SV:Eu3+ can be obtained through changing the concentration of Eu3+ or changing the relative quantities of SGV to SV by increasing the calcination temperature. Its excitation bands consist of two types of O2− → V5+ charge transfer (CT) bands with the peaks at about 325 and 350 nm respectively, as well as f–f transitions of Eu3+. The obtained warm-white emission consists of a broad photoluminescence band centred at about 530 nm, which originates from the O2− → V5+ CT of SV, and a sharp characteristic spectrum (5D0–7F2) at about 615 and 621 nm.The vanadate-based phosphors Sr2V2O7:Eu3+ (SV:Eu3+), Sr9Gd(VO4)7:Eu3+ (SGV:Eu3+) and Sr9Gd(VO4)7/Sr2V2O7:Eu3+ (SGV/SV:Eu3+) were obtained by solid-state reaction. 相似文献
999.
Examining practical nursing experiences to discover ways in which to retain and invigorate the remaining functions of the elderly with a demented and complex disability in nursing homes 下载免费PDF全文
Min‐Sun Park Sun‐Young Lim Eun‐Young Kim Su‐Jung Lee Sung‐Ok Chang 《Japan Journal of Nursing Science》2018,15(1):77-90
Aim
The bedridden elderly with moderate‐to‐severe dementia account for a large proportion of the residents in nursing homes and form a specialized group requiring customized care in order to encourage their remaining functions, which determine the quality of their residual life. The purpose of this study was to search for ways to invigorate and foster the remaining functions of this complex‐disability group, based on practical nursing strategies in nursing homes.Methods
The qualitative thematic analysis was done by conducting in‐depth interviews with 29 nurses working at 11 different nursing homes in South Korea.Results
This study proposed four main themes and 19 sub themes as keys for providing specialized nursing care to the elderly with physical and cognitive disabilities. The main themes encourage the residents' remaining functions: (i) accurate identification of an elderly resident's physical, cognitive, and behavioral baseline is necessary in order to determine their functional levels; (ii) nurses provide meticulous management to support the remaining functions in order to prevent further deterioration; (iii) optimized know‐how, based on accumulated experience and knowledge, is reflected in nursing strategies that maximize the effects of nursing interventions; and (iv) steady compliance with nursing guidelines and standards in nursing homes creates the best therapeutic environment and brings unexpected positive changes in the elderly's status.Conclusion
A practical nursing strategy to target the group with a demented and complex disability in nursing homes was developed through thematic analysis of the empirical knowledge of nurses. The findings provide new insights for developing specialized nursing interventions and practical nursing models in long‐term care facilities. 相似文献1000.
Biomaterial characterization of off‐the‐shelf decellularized porcine pericardial tissue for use in prosthetic valvular applications 下载免费PDF全文
Joshua A. Choe Soumen Jana Brandon J. Tefft Ryan S. Hennessy Jason Go David Morse Amir Lerman Melissa D. Young 《Journal of tissue engineering and regenerative medicine》2018,12(7):1608-1620
Fixed pericardial tissue is commonly used for commercially available xenograft valve implants, and has proven durability, but lacks the capability to remodel and grow. Decellularized porcine pericardial tissue has the promise to outperform fixed tissue and remodel, but the decellularization process has been shown to damage the collagen structure and reduce mechanical integrity of the tissue. Therefore, a comparison of uniaxial tensile properties was performed on decellularized, decellularized‐sterilized, fixed, and native porcine pericardial tissue versus native valve leaflet cusps. The results of non‐parametric analysis showed statistically significant differences (p < .05) between the stiffness of decellularized versus native pericardium and native cusps as well as fixed tissue, respectively; however, decellularized tissue showed large increases in elastic properties. Porosity testing of the tissues showed no statistical difference between decellularized and decell‐sterilized tissue compared with native cusps (p > .05). Scanning electron microscopy confirmed that valvular endothelial and interstitial cells colonized the decellularized pericardial surface when seeded and grown for 30 days in static culture. Collagen assays and transmission electron microscopy analysis showed limited reductions in collagen with processing; yet glycosaminoglycan assays showed great reductions in the processed pericardium relative to native cusps. Decellularized pericardium had comparatively low mechanical properties among the groups studied; yet the stiffness was comparatively similar to the native cusps and demonstrated a lack of cytotoxicity. Suture retention, accelerated wear, and hydrodynamic testing of prototype decellularized and decell‐sterilized valves showed positive functionality. Sterilized tissue could mimic valvular mechanical environment in vitro, therefore making it a viable potential candidate for off‐the‐shelf tissue‐engineered valvular applications. 相似文献