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71.
Kidney failure is a major health problem worldwide. Patients with end-stage renal disease require intensive medical support by dialysis or kidney transplantation. Current methods for diagnosis of kidney disease are either invasive or insensitive, and renal function may decline by as much as 50% before it can be detected using current techniques. The goal of this study was, therefore, to identify biomarkers of kidney disease (associated with renal fibrosis) that can be used for the development of a non-invasive clinical test for early disease detection. We utilized two protein-profiling technologies (SELDI-TOF MS and 2-D) to screen the plasma and kidney proteome for aberrantly expressed proteins in an experimental mouse model of unilateral uretric obstruction, which mimics the pathology of human renal disease. Several differentially regulated proteins were detected at the plasma level of day-3-obstructed animals, which included serum amyloid A1, fibrinogen α, haptoglobin precursor protein, haptoglobin and major urinary proteins 11 and 8. Differentially expressed proteins detected at the tissue level included ras-like activator protein 2, haptoglobin precursor protein, malate dehydrogenase, α enolase and murine urinary protein (all p<0.05 versus controls). Immunohistochemistry was used to confirm the up-regulation of fibrinogen. Interestingly, these proteins are largely separated into four major classes: (i) acute-phase reactants (ii) cell-signaling molecules (iii) molecules involved in cell growth and metabolism and (iv) urinary proteins. These results provide new insights into the pathology of obstructive nephropathy and may facilitate the development of specific assay(s) to detect and monitor renal fibrosis.  相似文献   
72.
In this article the development of a computer system for General Practice, ELIAS, is described. The use of the 4th-generation software toolkit AIDA proved to be very helpful in increasing the speed of development as well as the quality of the ELIAS software. The programming support that AIDA offered, not only in increasing the rate of development but also in the flexible way in which parts of the system and the database can be adjusted (in prototyping as well as in the operational system) and its self-documenting functions, contributed to the ease of development. The consistent lay-out of the frames and uniform screen-handling, the opportunity of data validation and the availability of help information at every item in screen frames--all facilitated by AIDA--rendered ELIAS a very user-friendly system.  相似文献   
73.
A quasilinearization algorithm is proposed to solve optimal control problems with a scalar control variable and a scalar state inequality constraint using a transformation technique. The optimal control problem is transformed into an unconstrained problem with an auxiliary control and higher dimension. Owing to the appearance of singular arcs in the transformed problem, this is made non-singular by adding a quadratic function of the auxiliary control to its performance index. A proposed quasilinearization algorithm is then used to generate a series of solutions of the modified transformed problems which converges to the solution of the original state-constrained problem in the limit. A distinct feature of the proposed algorithm is that each modified transformed problem yields a feasible trajectory of the original state-constrained problem. Two examples have been solved to illustrate the effectiveness of the proposed quasilinearization algorithm.  相似文献   
74.
75.
Granular biomass capable of partial nitritation and anammox   总被引:1,自引:0,他引:1  
A novel and efficient way of removing nitrogen from wastewater poor in biodegradable organic carbon, is the combination of partial nitritation and anoxic ammonium oxidation (anammox), as in the one-stage oxygen-limited autotrophic nitrification/denitrification (OLAND) process. Since anoxic ammonium-oxidizing bacteria grow very slowly, maximum biomass retention in the reactor is required. In this study, a lab-scale sequencing batch reactor (SBR) was used to develop granular, rapidly settling biomass. With SBR cycles of one hour and a minimum biomass settling velocity of 0.7 m/h, OLAND granules were formed in 1.5 months and the nitrogen removal rate increased from 50 to 450 mg N L(-1) d(-1) in 2 months. The granules had a mean diameter of 1.8 mm and their aerobic and anoxic ammonium-oxidizing activities were well equilibrated to perform the OLAND reaction. Fluorescent in-situ hybridization (FISH) demonstrated the presence of both beta-proteobacterial aerobic ammonium oxidizers and planctomycetes (among which anoxic ammonium oxidizers) in the granules. The presented results show the applicability of rapidly settling granular biomass for one-stage partial nitritation and anammox.  相似文献   
76.
Assessed the potential impact of stereotypical information on memory, using 107 undergraduates. Ss saw a series of slides depicting a violent knifing incident between 2 men on the London Underground. Half were shown the altercation as occurring between 2 White men and half between a Black and a White man. In all cases, the critical slide in which the knife was presented showed it to be in the hand of the White man. After a distraction interval of 45 min Ss were given forced-choice recognition and recall tests. The latter required the Ss to write a brief account of the event while the former required Ss to choose between 2 slides. Results indicate that, when the recognition test preceded the recall test, Ss who had seen the slides with the Black and White protagonists were less accurate than those who had seen only White protagonists. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
77.
To address the wide variety of solder joint configurations, the authors have developed and applied a physics-of-failure model to predicting the service life of solder joints under thermal cycling conditions. The wide variety of solder joint geometries, materials and environments makes it impractical to develop and apply empirical models to predicting the service life of solder joint interconnects. On the other hand, a physics-of-failure model that describes the failure mechanisms in solder joints can be applied to a wide range of conditions. The physics-of-failure model framework is described and a model is demonstrated for predicting the failure of a leadless surface mount solder joint under slow thermal cycling conditions.  相似文献   
78.
Multicasting is a desired function in both wired and wireless networks. Currently, multicasting‐based applications have pervasive presence and influence in our Internet. Wireless ATM aims to support different traffic types over a high speed wireless network. In particular, traditional approaches towards multicasting in wired networks cannot be directly applied to mobile ATM networks. This includes the mechanism proposed to handle mobility in wired networks. In this paper, we address the issues behind multicasting in wireless ATM networks and the underlying mechanisms to support handoffs of both unicast and multicast connections. Through simulation, we evaluated the performance of optimal core‐based tree (CBT), late‐joined CBT, optimal source‐based tree (SBT), and late‐joined SBT during changing multicast host membership conditions. In addition, we evaluated the impact of multicast receivers' migration on the total link cost of the resultant multicast tree. Simulation results revealed that source‐based trees incur more total link costs under both dynamic host membership and receivers' migration scenarios. However, it generates less control messages than the distributed CBT and SBT approaches. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
79.
Plastic flow localization in the yielding of mild steel is theoretically studied in terms of the instability of the uniform mode of yielding. The instability is judged by the small perturbation theory in which the development of non-uniform modes superimposed upon the basic uniform mode is examined. The constitutive equation of rate-dependent type and the criterion of yield initiation at the plastic-zone front are employed as the constitutive relations of mild steel. The results of the analysis show the relation between the instability and the characteristic nature of mild steel.  相似文献   
80.
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