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101.
OBSESSIVE–COMPULSIVE DISORDER (OCD) IS A COMMON and debilitating neuropsychiatric disorder. Although it is widely believed to have a genetic basis, no specific genetic factors have been conclusively identified as yet, leading researchers to look for environmental risk factors that may interact with an underlying genetic susceptibility in affected individuals. Recently, there has been increasing interest in a possible link between streptococcal infections and the development of OCD and tic disorders in children. It has been suggested that OCD in some susceptible individuals may be caused by an autoimmune response to streptococcal infections, that is, a similar biological mechanism to that associated with Sydenham's chorea. The term “pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections” (PANDAS) has been used to describe a subset of children with abrupt onset or exacerbations of OCD or tics, or both, following streptococcal infections. Affected children have relatively early symptom onset, characteristic comorbid symptoms and subtle neurological dysfunction. Neuroimaging studies reveal increased basal ganglia volumes, and the proposed cause involves the cross-reaction of streptococcal antibodies with basal ganglia tissue. Vulnerability to developing PANDAS probably involves genetic factors, and elevated levels of D8/17 antibodies may represent a marker of susceptibility to PANDAS. Prophylactic antibiotic treatments have thus far not been shown to be helpful in preventing symptom exacerbations. Intravenous immunoglobulin therapy may be an effective treatment in selected individuals. Further understanding of the role of streptococcal infections in childhood-onset OCD will be important in determining alternative and effective strategies for treatment, early identification and prevention of this common and debilitating psychiatric disorder. 相似文献
102.
103.
Delaram Shakoor Cesar de Cesar Netto Gaurav K Thawait Scott J Ellis Martinus Richter Lew C Schon Shadpour Demehri 《Foot and Ankle Surgery》2021,27(2):201-206
BackgroundOptimal characterization of Adult acquired flatfoot deformity (AAFD) on two-dimensional radiograph can be challenging. Weightbearing Cone Beam CT (CBCT) may improve characterization of the three-dimensional (3D) structural details of such dynamic deformity. We compared and validated AAFD measurements between weightbearing radiograph and weightbearing CBCT images.Methods20 patients (20 feet, right/left: 15/5, male/female: 12/8, mean age: 52.2) with clinical diagnosis of flexible AAFD were prospectively recruited and underwent weightbearing dorsoplantar (DP) and lateral radiograph as well as weightbearing CBCT. Two foot and ankle surgeons performed AAFD measurements at parasagittal and axial planes (lateral and DP radiographs, respectively). Intra- and Inter-observer reliabilities were calculated by Intraclass correlation (ICC) and Cohen’s kappa. Mean values of weightbearing radiograph and weightbearing CBCT measurements were also compared.ResultsExcept for medial-cuneiform-first-metatarsal-angle, adequate intra-observer reliability (range:0.61?0.96) was observed for weightbearing radiographic measurements. Moderate to very good interobserver reliability between weightbearing radiograph and weightbearing CBCT measurements were observed for the following measurements: Naviculocuneiform-angle (ICC:0.47), Medial-cuneiform-first-metatarsal-gapping (ICC:0.58), cuboid-to-floor-distance (ICC:0.68), calcaneal-inclination-angle(ICC:0.7), axial Talonavicular-coverage-angle(ICC:0.56), axial Talus-first-metatarsal-angle(ICC:0.62). Comparing weightbearing radiograph and weightbearing CBCT images, statistically significant differences in the mean values of parasagittal talus-first-metatarsal-angle, medial-cuneiform-first-metatarsal-angle, medial-cuneiform-to-floor-distance and navicular-to-floor-distance was observed (P < 0.05).ConclusionModerate to very good correlation was observed between certain weightbearing radiograph and weightbearing CBCT measurements, however, significant difference was observed between a number of AAFD measurements, which suggest that 2D radiographic evaluation could potentially underestimate the severity of AAFD, when compared to 3D weightbearing CT assessment. 相似文献
104.
Markus Walther Victor Valderrabano Martin Wiewiorski Federico Giuseppe Usuelli Martinus Richter Tiago Soares Baumfeld Johanna Kubosch Oliver Gottschalk Udo Wittmann 《Foot and Ankle Surgery》2021,27(3):236-245
BackgroundThe aim of this study is to systematically review the literature on clinical outcomes of patients who have undergone autologous matrix-induced chondrogenesis (AMIC) for treatment of osteochondral lesions of the talus (OCL) and compare the studies’ outcomes.MethodsPubmed and Embase were searched in January 2020 for articles concerning OCL surgery. Studies were included if they had a minimum 1-year follow-up and the primary measures were functional outcomes. The meta-analysis compared the Visual Analogic Score (VAS), the American Orthopedic Foot and Ankle Score (AOFAS), and the Foot Function Index (FFI) between baseline and follow-up of 1?2 years, and 3?5 years. A random effects model was used to evaluate outcome changes.ResultsThe search returned 15 studies, with a total of 492 patients. The VAS improved 4.45 and 4.6 points from baseline to the 1?2 year and 3?5 year follow-up, respectively (p < 0.001). AOFAS improved 31.59 and 32.47 points from baseline to the 1?2 year and 3?5 year follow-up, respectively (p < 0.001). The FFI showed a significant improvement of 30.93 points from baseline to year 3?5 (p < 0.001). A total of 6 patients with revision surgeries have been reported within the follow up period. It was not possible to correlate clinical features like lesion size, surgical approach, and bone marrow stimulation technique to the reported outcome.ConclusionSurgical treatment of OCL via the AMIC procedure provided significant improvement in the functional outcome and pain scores when compared to the pre-operative values. Improvements were observed up to 5 years post-operatively. 相似文献
105.
An experiment with N=40 university students investigated the impact of social observation on cardiovascular reactivity during performance on a computer-based letter detection task. The study was conducted in a 2 (social observation: no vs. yes)x2 (task difficulty: easy vs. difficult) between-persons design. In accordance with engagement-related predictions about the role of social observation in active coping, the mere presence of an experimenter who observed participants during task performance increased the reactivity of systolic blood pressure when the task was difficult, but not when the task was easy. Without social observation, reactivity was modest in both the easy and the difficult conditions. Reactivity of diastolic blood pressure described the same pattern as systolic blood pressure. Results are interpreted as evidence for an effort-related analysis of cardiovascular reactivity based on the principles of motivational intensity theory. 相似文献
106.
Pre-Botzinger complex in the cat 总被引:5,自引:0,他引:5
107.
Bisheriges Wissen zum Thema. Eine generell erh?hte psychosoziale Belastung der Eltern h?rbehinderter Kinder ist aus der Literatur bekannt. 相似文献
108.
D. Richter A. Bosse A. Weber K.-M. Müller G. Muhr 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1995,380(6):354-358
Zusammenfassung Es wird uber ein epitheloid-differenziertes Osteosarkom des distalen Oberschenkels mit nur minimaler Osteoidbildung and positiver Immunreaktion mit Antikörpern gegen das mesenchymale Zytoskelettprotein Vimentin bei einer 23jährigen Patientin berichtet. Metastasenverddchtige Areale fanden sich in der 5. Rippe sowie oberhalb des rechten Nierenpols. Bei fehlendem Ansprechen auf eine adjuvante Chemotherapie mußte aufgrund eines Lokalrezidivs 1 Jahr nach Tumorprothesenimplantation eine Oberschenkelamputation vorgenommen werden. Die Patientin verstarb 2,5 Jahre nach der Erstdiagnosestellung. Die Literaturberichte uber das seltener epitheloide Osteosarkom zeigen die Schwierigkeiten der differentialdiagnostischen Abgrenzung von der Metastase eines epithelialen Tumors.
Epitheloid osteosarcoma — problems with diagnosis
The case of a 23-year-old female patient suffering from a rare variety of osteosarcoma of the distal femur with epithelial differentiation and only traces of osteoid is reported. The tumour cells reacted strongly to antibodies against vimentin. Metastases were found in the fifth rib and the right kidney. There was no response to chemotherapy. One year after implantation of a tumour prothesis of the knee a thigh amputation was necessary because of a local failure. The patient died 2.5 years after the tumour had initially been diagnosed. Other reports of this rare type of epitheloid osteosarcoma illustrate the difficulties involved in reaching a correct diagnosis. This tumour can be mistaken for a skeletal metastasis of an epithelial tumour.相似文献
109.
Functionally intact in vitro preparation generating respiratory activity in neonatal and mature mammals 总被引:1,自引:1,他引:0
Julian F. R. Paton Jan -Marino Ramirez Diethelm W. Richter 《Pflügers Archiv : European journal of physiology》1994,428(3-4):250-260
The present report describes a novel rhythmically active brainstem slice preparation that generates respiratory activity spontaneously in both mice and rats of varying maturational states. The brainstems of neonatal (0–4 days) and mature (3–8 weeks) mice and rats were isolated and a 600- to 750-m thick slice cut to include the dorsomedial and the ventrolateral regions of the complete rostro-caudal extent of the medulla. This plane of section we have termed tilted-sagittal. Rhythmically discharging neurones were recorded extracellularly from both the dorsal and ventral regions of the slice. The recording sites of these neurones were found in the hypoglossal motonucleus (XII) and in areas of the ventrolateral medulla that includes the ventral respiratory group (VRG) region. Histological examination revealed the preservation of neuronal structures important for cardiorespiratory regulation and reflex control including the nucleus of the solitary tract as well as the nucleus ambiguus. In addition, pontine structures including the A5 region were also preserved. Rhythmic activity was found only in slices where the ambiguual column was preserved in its entirety. The mean frequency of discharge of XII neurones was 20 and 10 bursts per minute in neonates and mature rodents respectively. In preparations of mature animals we demonstrate that this frequency increased significantly (P<0.05) by either raising temperature from 29°C to 38°C (54%), elevating extracellular potassium concentration from 4 to 7.5 mM (52%), blocking potassium channels (20%) or decreasing pH from 7.4 to 7.0 (18%). The burst duration to frequency ratio of XII and VRG rhythmic neurones was similar and therefore indicative of a common brainstem oscillator. Consistent with this finding was that rhythmic activity in the VRG persisted despite removal of the dorsomedial region of the slice. In contrast, rhythmic XII neurones became tonic following mechanical disconnection of the VRG. 相似文献
110.
Arbizu J Insausti R Martí JM Manrique M Richter JA 《Anales del sistema sanitario de Navarra》1999,22(3):327-336
To evaluate the differences in the functional activity of the auditory cortex between normal hearing and profound deafness, a perfusion single photon emission tomography (SPECT) study was designed. SPECT stereotaxic localisation of the auditory cortex was previously validated in 2 brains by means of an anatomical study of the macroscopic localisation and cytoarchitecture of the auditory cortex. Additionally, 15 controls with normal hearing and 30 patients with profound bilateral deafness were scanned using external anatomical point sources (glabela, ineon) for stereotaxic location of the auditory cortex. The normal controls were scanned in auditive deprivation and, in 10 cases, during a monoaural tonal stimulation. Cerebral blood flow relative to cerebellum (relCBF) was assessed in the auditory cortex. The anatomical study showed that mean differences between the true auditory cortex size and the measured SPECT value were less than 2.5 mm. Nevertheless, only the caudal aspect of this area corresponded to the primary auditory cortex in the cytoarchitectonic study. During tonal stimulation, control subjects presented a significant increase of relCBF in the auditory cortex bilaterally, with significant differences in the asymmetry index (contralateral to the side of stimulation). The relCBF in the auditory cortex of controls in deprivation conditions was significantly higher than in deaf patients. There were no significant differences between groups of deaf patients, however the highest values were seen after cochlear implant. SPECT is a suitable method for studying changes in auditory cortex activity relative to different functional conditions, with a possible role in cochlear implant candidates in predicting the future benefit of the implantation. 相似文献