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排序方式: 共有2722条查询结果,搜索用时 15 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
2.
Kanghyun Kim Kwantae Noh Janghyun Paek Kung-Rock Kwon Ahran Pae 《The journal of advanced prosthodontics》2015,7(5):406-410
Russell-Silver syndrome (RSS) is a congenital disease characterized by short stature due to growth hormone deficiency, physical asymmetry, inverted triangular face, micrognathia, prominent forehead, and hypodontia. This case report presents a prosthetic management of a 6-year-old patient with Russell-Silver syndrome treated with overdentures on the maxilla and the mandible using the remaining primary teeth. Subsequent and comprehensive dental management considering the growth and development of a young patient will be necessary. 相似文献
3.
4.
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
5.
Transmembrane recordings and surface electrograms were used to evaluate the influence of propafenone on the cellular electrophysiology of isolated neonatal and adult rabbit atrioventricular node (AVN) preparations. An automatic interval of 863 +/- 82 ms (mean +/- SEM, n = 14) in neonates was found to be significantly shorter than the 1510- +/- 205-ms (n = 12) automatic interval observed in adults. Propafenone in a concentration of 5 x 10(-6) M significantly increased the automatic interval of neonatal pacemakers but not that of the adult preparations. These changes in automaticity produced by propafenone were not dependent on the adrenergic receptor-blocking action of the drug. The pacemaker escape time after overdrive pacing was also shorter in the neonate than in the adult. Propafenone prolonged the escape time of the neonatal tissues but not those of the adult. AVN refractory period, A-H interval, and antegrade Wenckebach rate were comparably increased in a concentration-dependent manner in both age groups. The maximum diastolic potential was decreased by propafenone in the neonatal atrionodal tissue but not in other regions of the AVN and not in any region of the adult AVN. Action-potential duration was increased in all regions of the AVN in both age groups. Action-potential amplitude and maximum upstroke velocity were decreased by propafenone in both age groups. Unlike other excitable tissues of the heart, the action-potential duration of AVN nodal cells increased with decreasing pacing intervals as the pacing interval approached the Wenckebach interval.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
6.
Fontan conversion with arrhythmia surgery. 总被引:2,自引:0,他引:2
Woong-Han Kim Hong Gook Lim Jeong Ryul Lee Joon Ryang Rho Eun Jung Bae Chung Il Noh Yong Soo Yoon Yong Jin Kim 《European journal of cardio-thoracic surgery》2005,27(2):250-257
OBJECTIVE: Hemodynamic abnormalities and refractory atrial arrhythmias in patients late after the Fontan operation result in significant morbidity and mortality. We reviewed our experience with Fontan conversion and concomitant arrhythmia surgery. METHODS: Between January 1996 and February 2004, 16 patients underwent Fontan conversion and arrhythmia surgery. Mean age at the initial Fontan operation was 5.1+/-3.5 (range: 2-15) years and mean age at Fontan conversion was 17.0+/-5.8 (range: 6-30). The initial Fontan operations were atriopulmonary connections in 14 patients, extracardiac lateral tunnel in 1, and intracardiac lateral tunnel in 1. The types of arrhythmia included atrial flutter in 10 patients and atrial fibrillation in 3. Fontan conversion operation was performed with intracardiac lateral tunnel in 5 patients and extracardiac conduit in 11. Arrhythmia surgery included isthmus cryoablation in 10 patients and right-sided maze in 3. RESULTS: There has been no mortality. At Fontan conversion operation, 7 patients required permanent pacemaker. All patients have improved to New York Heart Association class I or II. With a mean follow-up of 26.9+/-30.6 (range:1-87) months, 16 patients had sinus rhythm, 2 patients had transient atrial flutter which was well controlled, and 2 patients required permanent pacemaker during follow-up. CONCLUSIONS: Fontan conversion with concomitant arrhythmia surgery and permanent pacemaker placement is safe, improves New York Heart Association functional class, and has a low incidence of recurrent arrhythmias. In most patients, concomitant permanent pacemakers are needed. 相似文献
7.
8.
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