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81.
Human immunodeficiency virus (HIV)-associated nephropathy (HIVAN) is a clinicopathologic entity that includes proteinuria, azotemia, focal segmental glomerulosclerosis or mesangial hyperplasia, and tubulointerstitial disease. The incidence of HIVAN is increased in black patients and variable depending on the age and geographic area. The objective of this study was to describe relevant clinical and pathological findings in 30 children with HIVAN followed at the Children's National Medical Center in Washington, D.C. Our experience of the last 12 years showed a spectrum of HIVAN that seems to be coincident with the degree of acquired immunodeficiency syndrome (AIDS) symptomatology. By renal sonograms and frequent urinalysis, we identified children undergoing the early stages of HIVAN with enlarged echogenic kidneys, proteinuria, and "urine microcysts". HIVAN did not necessarily progress rapidly to end-stage renal disease. Nephrotic syndrome or chronic renal insufficiency were late manifestations of HIVAN. Children with HIVAN were likely to develop transient electrolyte disorders, heavy proteinuria, and acute renal failure due to systemic infectious episodes or nephrotoxic drugs. HIVAN was associated with other HIV-induced illnesses and high mortality rates. Early detection and careful clinical follow-up of children with HIVAN may reduce the incidence of renal-cardiovascular complications and improve their quality of life. 相似文献
82.
Local outlier detection reconsidered: a generalized view on locality with applications to spatial, video, and network outlier detection 总被引:1,自引:0,他引:1
Erich Schubert Arthur Zimek Hans-Peter Kriegel 《Data mining and knowledge discovery》2014,28(1):190-237
Outlier detection research has been seeing many new algorithms every year that often appear to be only slightly different from existing methods along with some experiments that show them to “clearly outperform” the others. However, few approaches come along with a clear analysis of existing methods and a solid theoretical differentiation. Here, we provide a formalized method of analysis to allow for a theoretical comparison and generalization of many existing methods. Our unified view improves understanding of the shared properties and of the differences of outlier detection models. By abstracting the notion of locality from the classic distance-based notion, our framework facilitates the construction of abstract methods for many special data types that are usually handled with specialized algorithms. In particular, spatial neighborhood can be seen as a special case of locality. Here we therefore compare and generalize approaches to spatial outlier detection in a detailed manner. We also discuss temporal data like video streams, or graph data such as community networks. Since we reproduce results of specialized approaches with our general framework, and even improve upon them, our framework provides reasonable baselines to evaluate the true merits of specialized approaches. At the same time, seeing spatial outlier detection as a special case of local outlier detection, opens up new potentials for analysis and advancement of methods. 相似文献
83.
Christian Friebe Martin D. Hager Andreas Winter Ulrich S. Schubert 《Advanced materials (Deerfield Beach, Fla.)》2012,24(3):332-345
Electropolymerization represents a suitable and well‐established approach for the assembly of polymer structures, in particular with regard to the formation of thin, insoluble films. Utilization of monomers that are functionalized with metal complex units allows the combination of structural and functional benefits of polymers and metal moieties. Since a broad range of both electropolymerizable monomers and metal complexes are available, various structures and, thus, applications are possible. Recent developments in the field of synthesis and potential applications of metal‐functionalized polymers obtained via electropolymerization are presented, highlighting the significant advances in this field of research. 相似文献
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86.
The WWW has become one of the most important media for sharing information. Web information provides another emerging and important avenue and source of competitive intelligence (CI) for companies. CI is critical for companies to stay competitive in the marketplace. Apart from business users, there are other types of CI users such as technical users, casual users, news awareness users and others who would like to be kept informed on the latest development of their interested areas over the WWW. To discover web information, CI users need to constantly monitor certain web sites and web pages for related information. However, the dynamic nature of the web has made such monitoring task complicated and time-consuming. This paper proposes a web monitoring system, WebMon, to help users monitor specified web pages for latest changes and updates in information. Four monitoring functions including date monitoring, keywords monitoring, link monitoring and portion monitoring are supported by the system. The performance of these monitoring functions is also evaluated. 相似文献
87.
k-nearest neighbor (k-NN) queries are well-known and widely used in a plethora of applications. However, in the original definition of k-NN queries there is no concern regarding diversity of the answer set with respect to the user’s interests. For instance, travelers may be looking for touristic sites that are close to where they are, but that would also lead them to see different parts of the city. Likewise, if one is looking for restaurants close by, it may be more interesting to learn about restaurants of different categories or ethnicities which are nonetheless relatively close. The interesting novel aspect of this type of query is that there are two competing criteria to be optimized: closeness and diversity. We propose two approaches that leverage the notion of linear skyline queries in order to find the k diverse nearest neighbors within a radius r from a given query point, or (k, r)-DNNs for short. Our proposed approaches return a relatively small set containing all optimal solutions for any linear combination of the weights a user could give to the two competing criteria, and we consider three different notions of diversity: spatial, categorical and angular. Our experiments, varying a number of parameters and exploring synthetic and real datasets, in both Euclidean space and road networks, respectively, show that our approaches are several orders of magnitude faster than a straightforward approach. 相似文献
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89.
W. Weissflog H. Schubert S. Knig D. Demus L. Vogel 《Advanced Synthesis \u0026amp; Catalysis》1977,319(3):507-515
Liquid-crystallin Ketoxime Esters Disubstituted acetophenoneoximebenzoates 1a – q , 2a – j , a – d , 4a – b and 5a – b are nematic liquid crystals that exhibit remarkable thermal stability and, dependent on their terminal groups, relative low melting points. Binary and ternary mixtures, for which also the melting temperatures have been evaluated theoretically, are liquid far below room temperature and stable under the influence of a. c. fields. The substitution of CH3 by C2H5 or n-C3H7 in 6a – d and 7 leads to pronounced depressions in the clearing points. 相似文献
90.
H. Heberer H. Hartung B. Lukowczyk H. Schubert 《Advanced Synthesis \u0026amp; Catalysis》1977,319(6):1015-1020
Intramolecular Quinhydrones. III. Colour and Charge-transfer Interactions The intensive colour of the crystalline intramolecular quinhydrones 2a – o depends on the substitution and the unsymmetrical bridge-structure. The solutions are yellow coloured. According to the x-ray, i.r.- and u.v./vis-results there are for 2a–o inter, but no intramolecular CT-complexes. 相似文献