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81.
Several functional MR imaging studies evaluating the lateralisation of linguistic functions in patients who underwent Wada testing have been reported. There is extensive variance in the Laterality index (LI) calculation across the studies, and the optimal calculation method remains unclear. We attempted to calculate the LI in different ways in the same subjects, in order to find the LI calculation method with the highest correlation to the Wada test. Fifteen patients (10 females, 5 males) suffering from medically intractable temporal lobe epilepsy (TLE) (12 left, 3 right) were admitted for the study. The patients underwent a standardized bilateral intracarotid short-acting barbiturate test. Language testing included spontaneous speech, oral comprehension, reading, object and picture naming, and repetition. All the tasks were scored separately in order to increase the possibility of correlation between Wada and LI. A silent phonemic verbal fluency task (VFT) was used as a language paradigm for functional measurement. Regions of interest (ROIs), with a known association with language function (Broca’s area, the lateral prefrontal cortex, etc.), were defined. First, the LIs were calculated from the ROIs using a previously reported method (simple suprathreshold count). Next, we used several new methods of LI calculation (t–weighting of voxels, methods independent of the choice of the statistical threshold, etc.) The most significant correlation with Wada was proven in the LIs that were evaluated from Broca’s area (up to R = 0.94, P = 1 × 10−7). However, the new LI calculation methods used in the present study did not produce a statistically significant benefit in comparison to previously reported methods.  相似文献   
82.
To address the extent to which the visual foveal representation is split, we examine the case of a patient, M.B., suffering from a left mesial occipital lesion and presenting a pure left hemialexia and a right hemianopia with a spared area of the macula. Reading performance on tachistoscopically presented four-letter words and pseudowords in the spared area of the right visual field was significantly better than reading performance in the intact left visual field. Reading performance in the spared area of the right visual field was also significantly better than reading performance of stimuli centred on the fovea. Moreover, a length effect was found only in the left half of pseudowords centred on the fovea, but not in the right half (up to five letters). These differences in reading efficiency between the left and right halves of the foveal region militates in favour of the split fovea theory and cannot be explained by the bilateral projection theory.  相似文献   
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Computed-assisted surgery (CAS) has been designed to improve oral implant planning and positioning and to increase safety and operator comfort. This is especially important in the esthetic zone, at sites with bone deficiency, and when minimally invasive implant placement is the therapy of choice. Current available CAS systems are relatively large and expensive and require a lengthy learning period. This report presents a novel tactile imaging and registration concept that enables the operation of a newly developed computerized implant locating system. An intraoral bone-sounding device maps the surface of the jaw through the soft tissue. Bone contour data are registered over the computerized tomographic image. Guided by treatment preplanning software, a chairside robotic manipulator fabricates guiding sleeves that direct the drill and implant during the osteotomy and implant placement, respectively. The authors' clinical experience shows that tactile registration based the Implant Locating System is simple to use and provides accurate implant design and placement that requires only basic computer experience, minimal operational space, and low infrastructure investment. The system allows final adjustments at the time of operation, transforming each implant surgery into a fully monitored procedure.  相似文献   
86.
BACKGROUND: Absence of medical documents damages the quality of treatment and service. Despite the computerized medical folder, its use is still limited, and not all countries have a national health communications systems. That is why the patients are asked to bring with them the documents they hold. However, some patients lose the documents and others are uncooperative due to forgetfulness, and a lack of knowledge. OBJECTIVES: To examine how patients perceive, keep and manage medical documents. DESIGN: The research was conducted in the qualitative method. SETTINGS: A cardiology clinic, in a big medical center in Israel. PARTICIPANTS: A total of 28 patients suffering from ischemic heart disease and/or rhythm disorders. The sample was a convenience one, and were taken from the population visiting the Cardiology Clinic from May to October 2003. METHODS: Semi-structured interviews were held with the participants. The data were processed by means of content analysis. RESULTS: The findings indicate that, even though the participants expressed that it is the health system's responsibility to manage medical documents, most of them kept, and some even managed, their medical documents via a personal folder. By keeping documents and deciding to whom and when to show them the patient functions as a self-care manager. This made them more involved in their treatment and, they felt in control and empowered. CONCLUSION: Patient's attention to documents, as keeper and router, results in demonstrations of responsibility and involvement in treatment, consequently empowering the patient.  相似文献   
87.
Graefe's Archive for Clinical and Experimental Ophthalmology - The coronavirus disease (COVID-19) pandemic has evolved into a formidable healthcare crisis. Ophthalmologists are at daily...  相似文献   
88.
The mortality rate after the development of postinfarction ventricular septal defect (VSD) remains high, despite progress in pharmacologic therapy, invasive cardiology, and surgical techniques. We present three cases of preoperative venoarterial extracorporeal membrane oxygenation as a bridge to reparative surgical repair in patients with cardiogenic shock who would otherwise require emergent cardiac surgery with an associated risk. Two patients were discharged, whereas the third patient died due to pulmonary artery rupture after a right ventricular assist device implantation, despite the fact that he had a successful bridge to reparative surgery and VSD repair. Finally, a review of the current literature concerning the use of preoperative venoarterial extracorporeal membrane oxygenation as a bridge to reparative surgery is provided.  相似文献   
89.
Template reaction between 5-methylsalicylaldehyde and 2-hydroxy-1,3-propanediamine in the presence of copper ion led to dinuclear and mononuclear copper(ii) complexes [Cu2L(CH3COO)(CH3OH)](CH3OH) (1) and [CuHL](CH3OH) (2), where H3L is N,N′-bis(5-methylsalicylidene)-2-hydroxy-1,3-propanediamine. The result of the reactions between 5-methylsalicylaldehyde and 2-hydroxy-1,3-propanediamine in the presence of lanthanide ions and/or copper(ii) ion was N,N′-bis(5-methylsalicylidene)-2-hydroxy-1,3-propanediamine (H3L B) or [CuHL](CH3OH) (2), respectively. Structures of the compounds were determined by single-crystal X-ray diffraction and physicochemical methods. The microstructures and phase compositions of crystals were studied by scanning electron microscopy (SEM). In dinuclear complex [Cu2L(CH3COO)(CH3OH)](CH3OH) (1), two copper(ii) ions are bond to one H3L ligand and one acetate ion. Coordination modes of the two copper centers are different: the geometry of copper 1 is almost ideal square-planar, while that for copper 2 can be described as tetragonal pyramidal. In complex [CuHL](CH3OH) (2), the copper(ii) ion is four coordinated and the coordination, rather than square-planar, can be described as flattened tetrahedral. Formation of complexes between copper(ii) or lanthanide ions with N,N′-bis(5-methylsalicylidene)-2-hydroxy-1,3-propanediamine (H3L) was also studied in solution by pH potentiometry. It should be mentioned that the complexes of lanthanide ions exist only in solution. Additionally, the salen-type ligand H3L and its dinuclear and mononuclear copper(ii) complexes were studied by cyclic voltammetry, and their spectroelectrochemical properties were examined.

The self-assembled metal-promoted synthesis and properties of N,N′-bis(5-methylsalicylidene)-2-hydroxy-1,3-propanediamine (H3L) complexes with d- and f-metal ions are described.  相似文献   
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