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31.
Somatosensory evoked potentials (SEPs) were used for continuous monitoring of 210 patients during anterior surgery for cervical myeloradiculopathy, to test how effectively they help avoid irreversible neurological damage during surgery. The pathologies differed in severity and were treated by diskectomy or by extended corporectomy using the Senegas technique. Intraoperative SEP changes were recorded in 84 patients (40%); in 13 (6.2%) of these, changes in SEP amplitude and latency were caused by mechanical stress. SEPs revealed transient episodes of regional ischaemia or neurophysiological anomalies during anaesthesia (mainly hypotension) in 27 patients (12.8%). The traces detected incipient and potentially dangerous mechanical pressure on, or metabolic anomalies of, the spinal cord during manipulation and placement procedures of spinal fixation devices. They were particularly sensitive indicators of ischaemia; one of the most common causes of irreversible injury. The traces of 44 patients (21.0%) improved markedly during surgery. There were no false-negatives in this series and, thanks to the fact that SEPs gave immediate warnings of incipient ischaemia to the surgical team, we had no case of irreversible medullary or nerve-root deficit.  相似文献   
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International Journal of Speech Technology - Due the property of the chaotic systems by means of randomness, sensitivity to the initial values and large size of keys, chaos masking plays a vital...  相似文献   
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Compared with conventional tumor photothermal therapy (PTT), mild‐temperature PTT brings less damage to normal tissues, but also tumor thermoresistance, introduced by the overexpressed heat shock protein (HSP). A high dose of HSP inhibitor during mild‐temperature PTT might lead to toxic side effects. Glucose oxidase (GOx) consumes glucose, leading to adenosine triphosphate supply restriction and consequent HSP inhibition. Therefore, a combinational use of an HSP inhibitor and GOx not only enhances mild‐temperature PTT but also minimizes the toxicity of the inhibitor. However, a GOx and HSP inhibitor‐encapsulating nanostructure, designed for enhancing its mild‐temperature tumor PTT efficiency, has not been reported. Thermosensitive GOx/indocyanine green/gambogic acid (GA) liposomes (GOIGLs) are reported to enhance the efficiency of mild‐temperature PTT of tumors via synergistic inhibition of tumor HSP by the released GA and GOx, together with another enzyme‐enhanced phototherapy effect. In vitro and in vivo results indicate that this strategy of tumor starvation and phototherapy significantly enhances mild‐temperature tumor PTT efficiency. This strategy could inspire people to design more delicate platforms combining mild‐temperature PTT with other therapeutic methods for more efficient cancer treatment.  相似文献   
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Shape-based interpolation of multidimensional objects   总被引:16,自引:0,他引:16  
A shape-based interpolation scheme for multidimensional images is presented. This scheme consists of first segmenting the given image data into a binary image, converting the binary image back into a gray image wherein the gray value of a point represents its shortest distance (positive value for points of the object and negative for those outside) from the cross-sectional boundary, and then interpolating the gray image. The set of all points with nonnegative values associated with them in the interpolated image constitutes the interpolated object. The method not only minimizes user involvement in interactive segmentation, but also leads to more accurate representation and depiction of dynamic as well as static objects. The general methodology and the implementation details of the method are presented and compared on a qualitative and quantitative basis to the existing methods. The generality of the proposed scheme is illustrated with a number of medical imaging examples.  相似文献   
36.
Raya Nour 《国际水》2013,38(7):908-925
ABSTRACT

The study analyzes the regulation reform process of the Palestinian urban water sector. It introduces the holistic reform agenda and examines the water supply sector’s performance and regulation challenges. The study also evaluates the perception of water service providers regarding the regulation reforms. Collected evidence indicates a dominant interpretation of the regulation concept based on rules and legislation, coupled with a neglect of aspects like monitoring, economic regulation and managerial accountability. The lack of awareness of the benefits of these aspects for service providers can increase resistance to reform and reduce willingness to participate in implementing comprehensive sector regulation.  相似文献   
37.
Rats injected repeatedly with the dopamine agonist quinpirole develop motor rituals that evolve through a cascade of 4 behavioral processes. The 1st involves increased activity. The 2nd involves increased path stereotypy, reflected in traveling repeatedly along the same few paths. The 3rd is an increase in the frequency of stopping in a few places, along with a decrease in stopping in other places. The 4th is a decrease in the repetition of movements performed in the specific stopping places. Altogether, these processes culminate in stereotypy, a typical short set of movements composed of a single performance of each movement type. Thus, stereotypy arises from changes in the temporal and spatial organization, but not the content, of behavioral patterns. These results provide a model for the development of motor rituals and their linkage to normal behavior and to the physical properties of the environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
38.
Soil erosion, runoff and nutrient-loss patterns over a two-year period (1999-2000) were monitored in erosion plots on a mountainside with olive (Olea europaea cv. Picual) trees under three different types of soil management: (1) non-tillage with barley (Hordeum vulgare) strips of 4 m width (BS); (2) conventional tillage (CT); (3) non-tillage without plant strips (NT). The erosion plots, located in Lanjaron (Alpujarras) on the southern flank of the Sierra Nevada Mountains in south-eastern Spain, had 30% slope at an altitude of 565 m and 192 m(2) (24x8 m) in area. The highest erosion and runoff values, ranging from 10.5 to 40.7 t ha(-1) yr(-1) and from 26.5 to 51.5 mm yr(-1), respectively, over the entire study period, were measured under NT. In CT, erosion ranged from 1.0 to 10.4 t ha(-1) yr(-1) and runoff from 6.7 to 15.2 mm yr(-1), while under BS, erosion ranged from 1.7 to 2.4 t ha(-1) yr(-1) and runoff from 19.6 to 20.0 mm yr(-1). It is concluded that the BS and CT reduced the soil erosion by 92% and 78%, with respect to the NT, and the runoff by 49% and 72%, respectively. The total NPK losses (sediments and runoff) from BS averaged 0.87, 0.07 and 0.72 kg ha(-1), from CT 1.82, 0.11 and 0.97 kg ha(-1) and from NT 3.15, 0.29 and 2.45 kg ha(-1), respectively. In addition, nutrient concentrations in the surface runoff were higher than the recommended level for standard water quality for N-NO(3), N-NH(4) and soluble P, particularly from NT and CT. These results support the recommendation of non-tillage with barley strips for sloped agricultural land in order to reduce erosion and pollution.  相似文献   
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SECURING VEHICULAR COMMUNICATIONS   总被引:1,自引:0,他引:1  
The road to a successful introduction of vehicular communications has to pass through the analysis of potential security threats and the design of a robust security architecture able to cope with these threats. In this article we undertake this challenge. In addition to providing a survey of related academic and industrial efforts, we also outline several open problems  相似文献   
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