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1.
The basis of the examination is a clinical material of 14 years (from 1960 to 1973) of the urological clinic of the Medical University "Semmelweis", consisting of 160 patients with renal hypoplasia. In 116 of these cases a nephrectomy was performed. The average postoperative observation time was 7.8 years. By removal of the hypoplastic kidney the hypertension could be successfully influenced in 72% of the cases and in 16% moderately; in 12% of the patients the high blood pressure remained unchanged also after the intervention. On account of the recognition resulting from the examinations that by the hypoplastic kidney alone no increase of the blood pressure is caused, but the developmental anomaly forms a basis for the development of the hypertension, is emphasized that the early removal of this abnormally developed kidney is by all means indicated.  相似文献   
2.
Multimedia Tools and Applications - Ubiquitous and networked sensors impose a huge challenge for privacy protection which has become an emerging problem of modern society. Protecting the privacy of...  相似文献   
3.
The methylated analogues of ß-cyclodextrin dissolve in cold water 10 – 20 times better than ß-cyclodextrin itself, however, quite unusually on heating they crystallize from the solution. The structure of heptakis-(2,6-di-O-methyl)- and heptakis-(2,3,6-tri-O-methyl)-ß-cyclodextrin was proved by gas-liquid chromatographic and 1H-NMR and 13C-NMR spectroscopic investigations. The corresponding model compounds were synthetized and, according to 13C-NMR spectroscopic investigations, a part of the so far published NMR assignations have to be corrected.  相似文献   
4.
A Pt/AlSBA-15 catalyst was investigated in the selective isomerisation of Fischer?CTropsch wax, which type of catalyst have not been studied in detail in this reaction system yet. Its hydroconversion activity was compared with that of the Pt/SAPO-11 catalyst. Based on the results it was concluded that the selective isomerization of the Fischer?CTropsch wax can be a new application of the Pt/AlSBA-15 catalyst.  相似文献   
5.
We show that many NP-hard sets have heuristic polynomial-time algorithms with high probability weight of correctness with respect to generalizations of Procaccia and Rosenschein’s junta distributions.  相似文献   
6.
Proprietary polyurea‐based thermosets were produced from polyisocyanate and water glass (WG) using a phosphate‐type phase transfer catalyst. WG was dispersed in the polyisocyanate resulting in water‐in‐oil (W/O) type emulsion. The polyurea matrix, formed after crosslinking, contained the WG derived silicate in coarse particles showing a broad particle size distribution. The mean particle size of the silicate was markedly reduced and its distribution narrowed when the polyisocyanate was hybridized with a peroxide crosslinkable vinylester resin (VE) when the amount of the latter was <75%. This resin hybridization strongly improved the mechanical (flexural) properties of the related thermosets, however, at cost of the fracture mechanical characteristics (fracture toughness and energy under mode I condition). This was mostly attributed to the formation of a conetwork or interpenetrated network between the polyurea and VE. The static flexural and fracture mechanical properties were determined as function of the resin hybridization ratio. It was found that the mechanical properties change according to the additivity rule as a function of the resin hybridization in the first approximation. The silicate dispersion and the failure behavior in the polyurea/VE hybrids were studied by scanning electron microscopy (SEM) and discussed. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 853–859, 2007  相似文献   
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We prove that every distributional problem solvable in polynomial time on the average with respect to the uniform distribution has a frequently self-knowingly correct polynomial-time algorithm.  相似文献   
9.
In field trapping tests, the catch of Chrysoperla carnea sensu lato (Neuroptera: Chrysopidae) increased when acetic acid was added to lures with phenylacetaldehyde. The addition of methyl salicylate to the binary mixture of phenylacetaldehyde plus acetic acid increased catches even further. The ternary blend proved to be more attractive than β-caryophyllene, 2-phenylethanol, or 3-methyl eugenol (compounds previously described as attractants for chrysopids) on their own, and no influence on catches was recorded when these compounds were added as fourth components to the ternary blend. There were minimal changes in activity when (E)-cinnamaldehyde or methyl anthranylate (both evoking large responses from female or male antennae of C. carnea in this study) were added, although both compounds showed significant attraction on their own when compared to unbaited traps. In subtractive field bioassays with the ternary mixture, it appeared that the presence of either phenylacetaldehyde or methyl salicylate was important, whereas acetic acid was less so in the ternary mixture. The ternary blend attracted both female and male lacewings at sites in southern, central, and northern Europe. Possible applications of a synthetic attractant for lacewings are discussed.  相似文献   
10.
Following the observation that the activity of gonadotropin-releasing hormone III (GnRH-III) in the suppression of growth of MDA-MB-231 and MCF-7 breast cancer cells surpasses that of GnRH and other analogs thereof, analogs of GnRH-III were synthesized to investigate the structural basis for the improved antitumor activity. Compounds synthesized include analogs with changes in the central sequence in which GnRH-III differs from GnRH and in the C- and N-terminal regions. The results indicate that a salt bridge between Asp6 and Lys8 stabilizes the active conformation of GnRH-III and show the importance of the Trp7. Replacement of the C-terminal Gly-NH2 with D-Ala-NH2 was not well tolerated, but replacement with ethylamide was. Replacement of pGlu1 with Ac-D-Trp appears to have a significantly deleterious effect on a unique conformation of GnRH-III which is responsible for its binding to the receptors on cancer cell lines and the resultant antitumor activity.  相似文献   
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