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排序方式: 共有1014条查询结果,搜索用时 31 毫秒
1.
Laura Heil Laura Maltry Sebastian Lehmann Daniel Heil Christoph Lehmann Stefan Kopp 《Cranio : the journal of craniomandibular practice》2021,39(1):35-46
ABSTRACT Objective: The purpose of this study was to examine the influence of a total knee arthroplasty (TKA) on linked cranial and caudal structures. Methods: Thirty-five (14f/21m) subjects participated in this study: 15 subjects (9f, 6m) pre- and post- TKA and a control group of 20 subjects (5f, 15m). The measurements included: jaw condyle position and movement, back scan, plantar pressure distribution, and body sway. Results: There were no significant differences in electronic position analysis of the jaw; however, the protrusion of the TKA group improved (p = 0.001). The test group had a more anteriorly inclined thoracic spine and a less pronounced lumbar lordosis. Before and after surgery, the body sway in the test group was larger. Conclusion: The TKA affected most prominently the static mechanisms of the postural control and the spine position. The trajectories of the mandible during protrusion also changed slightly. 相似文献
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Previously we have shown that the dorsal lateral geniculate body (LGB), which is strictly visual in sighted mammals, receives a strong auditory input in the naturally blind mole rat (Spalax ehrenbergi). Here we show with the 2-deoxyglucose technique and with single-unit recordings that in this species the initially non-degenerated visual cortex, as defined by its connection with LGB, is also activated by the auditory modality. These findings suggest that cross-modal compensation may occur as a natural consequence of the degeneration of a sense organ. 相似文献
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The advantages of the new, safer, but more expensive iodinated contrast agents are discussed, and opinions on which patient groups should receive the agents are presented. 相似文献
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Bei den akuten myeloischen Leuk?mien (AML) handelt es sich um heterogene, maligne Erkrankungen des h?matopoetischen Systems,
denen die maligne Transformation einer h?matopoetischen Vorl?uferzelle zugrunde liegt [9]. Folge dieser Transformation ist
ein Verlust oder die Einschr?nkung des Differenzierungspotentials der Zellen mit einem Ausreifungsstop auf einem frühen Stadium
der Myelopoese. Bei erhaltener Proliferationskapazit?t kommt es zur klonalen Expansion der malignen Zellen mit sukzessiver
„Verdr?ngung” der normalen H?matopoese, an deren Folgen der Patient unbehandelt innerhalb weniger Wochen verstirbt. Haupttodesursachen
sind Blutungen und /oder Infektionen. 相似文献
9.
The existence of an ontogenetic shift of tonotopic organization throughout the auditory pathway concomitant with cochlea maturation is a matter of controversy. Using the 2-deoxyglucose method we demonstrate here for the first time the shift phenomenon in an auditory forebrain structure, field L, the auditory cortex analogue of the chick. During the first postnatal month isofrequency contours move to positions where, in younger chicks, lower frequencies (up to half an octave) are represented. This developmentally changing place code of sound frequencies at the forebrain level is similar to the one previously reported for brain stem auditory nuclei. It raises the question of constancy of frequency-related pitch perception during development and may be a complication of early auditory learning and memory. 相似文献
10.
Tumor targeting by an aptamer. 总被引:10,自引:0,他引:10
Brian J Hicke Andrew W Stephens Ty Gould Ying-Fon Chang Cynthia K Lynott James Heil Sandra Borkowski Christoph-Stephan Hilger Gary Cook Stephen Warren Paul G Schmidt 《Journal of nuclear medicine》2006,47(4):668-678
Aptamers are small oligonucleotides that are selected to bind tightly and specifically to a target molecule. We sought to determine whether aptamers have potential for in vivo delivery of radioisotopes or cytotoxic agents. METHODS: TTA1, an aptamer to the extracellular matrix protein tenascin-C, was prepared in fluorescent and radiolabeled forms. After in vivo administration, uptake and tumor distribution of Rhodamine Red-X-labeled aptamer was studied by fluorescence microscopy. In glioblastoma (U251) and breast cancer (MDA-MB-435) tumor xenografts, biodistribution and imaging studies were performed using TTA1 radiolabeled with (99m)Tc. Tenascin-C levels and tumor uptake were studied in a variety of additional human tumor xenografts. To assess the effect of radiometal chelate on biodistribution, mercapto-acetyl diglycine (MAG(2)) was compared with diethylenetriaminepentaacetic acid and with MAG(2)-3,400-molecular-weight PEG (PEG(3,400)). RESULTS: Intravenous injection of fluorescent aptamer TTA1 produced bright perivascular fluorescence in a xenografted human tumor within 10 min. In the ensuing 3 h, fluorescence diffused throughout the tumor. Labeled with (99m)Tc, TTA1 displayed rapid blood clearance, a half-life of less than 2 min, and rapid tumor penetration: 6% injected dose (%ID)/g at 10 min. Tumor retention was durable, with 2.7 %ID/g at 60 min and a long-lived phase that stabilized at 1 %ID/g. Rapid tumor uptake and blood clearance yielded a tumor-to-blood ratio of 50 within 3 h. Both renal and hepatic clearance pathways were observed. Using the (99m)Tc-labeled aptamer, images of glioblastoma and breast tumors were obtained by planar scintigraphy. Aptamer uptake, seen in several different human tumors, required the presence of the target protein, human tenascin-C. Modification of the MAG(2) radiometal chelator dramatically altered the uptake and clearance patterns. CONCLUSION: TTA1 is taken up by a variety of solid tumors including breast, glioblastoma, lung, and colon. Rapid uptake by tumors and rapid clearance from the blood and other nontarget tissues enables clear tumor imaging. As synthetic molecules, aptamers are readily modified in a site-specific manner. A variety of aptamer conjugates accumulate in tumors, suggesting imaging and potentially therapeutic applications. 相似文献