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941.
A 15-year-old girl is described with the sicca syndrome of keratoconjunctivitis and xerostomia. There was no associated rheumatoid arthritis or other connective tissue disorder, but total lipodystrophy had been present since the age of 9 years. Marked hyperreactivity of the humoral immune system and suppression of cell-mediated immunity was shown. The association of sicca syndrome with total lipodystrophy has not previously been reported. 相似文献
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944.
The software development industry often brings in security at the eleventh hour, right before developers throw the code over the wall--that is, deploy it into production--and ask, "Well, is it secure?" At this point, hilarity--for the objective observers, anyhow--ensues as security personnel work feverishly to shove crypto, firewalls, and all the other mechanisms at their disposal into the most egregious risk areas. This article describes how to create useful misuse cases within the development process, thus avoiding the headaches that can arise toward the end of the cycle. 相似文献
945.
Mammalian xanthine oxidoreductase exists intracellularly in its dehydrogenase form. However, outside of this reducing milieu the enzyme quickly transforms into an oxidase form. Interconversion can be controlled by sulfhydryl reactive reagents, suggesting that disulfide bridging is linked to this phenomenon. The present work identified cysteines involved in the interconversion process. Purified enzyme was subjected to mild reduction with 1,4-dithioerythriol to regain dehydrogenase activity, and the accessible cysteines were labeled with specific radioactive alkylation reagents, iodoacetic acid. This partial alkylation stabilizes the dehydrogenase form, presumable by hindering formation of disulfide bond(s). Six of 38 cysteines were found to be labeled (residues 169, 170, 535, 992, 1317, and 1325). The significance of this labeling of bovine xanthine oxidoreductase is discussed in relation to structural knowledge about the enzyme, and especially by comparison with the AA sequences of avian and invertebrate enzymes, which do not undergo conversion. Cysteines 535 and 992 are the most likely marked residues to be involved in the interconversion, whereas the other cysteines are located too far from the cofactorbinding areas in xanthine oxidoreductase. 相似文献
946.
The presence of the RN(-)-gene determined in 72 halothane negative Danish pigs, either by a direct genotyping or the glycolytic potential of the meat, in relation to drip loss, was investigated. The drip loss in the M. longissimus dorsi from RN-carriers (n=26), as determined by genotyping was 9.9% compared to 8.6% in non-carriers (n=46) (P=0.07). When a glycolytic potential of >230 μmol lactate/g meat was used to differentiate between carriers and non carriers of the RN(-)-gene, the drip loss in carriers was 10.6% (n=17) compared to 8.7% in non-carriers (n=55) (P<0.01). These results suggest that the presence of the RN(-)-gene in Danish slaughter pigs only partially explains the large variation in drip loss observed in Danish pork. 相似文献
947.
We present a theoretical analysis of the lateral modes of a broad-area semiconductor laser. The structure of the modes are classified into four categories and the modes are traced in the frequency versus pump rate diagram. It is shown how the branches of the frequency tuning curves for the different types of modes are interconnected and how the intensity profiles develop along the branches. The main result of the paper is the presentation of a small-signal stability analysis which identifies the saddle-node and Hopf bifurcation points on the mode tuning curves. For stable modes we derive expressions for small-signal noise and modulation spectra and present numerical examples of the spectra. 相似文献
948.
Lars‐Peter Ellekilde Henrik Gordon Petersen 《International journal for numerical methods in engineering》2006,67(10):1445-1466
In this paper, we will extend the linear complementarity problem‐based rigid‐body simulation framework with non‐holonomic constraints. We consider three different types of such, namely equality, inequality and contact constraints. We show how non‐holonomic equality and inequality constraints can be incorporated directly, and derive formalism for how the non‐holonomic contact constraints can be modelled as a combination of non‐holonomic equality constraints and ordinary contacts constraints. For each of these three we are able to guarantee solvability, when using Lemke's algorithm. A number of examples are included to demonstrate the non‐holonomic constraints. Copyright © 2006 John Wiley & Sons, Ltd 相似文献
949.
Julia Matena Svea Petersen Matthias Gieseke Michael Teske Martin Beyerbach Andreas Kampmann Hugo Murua Escobar Nils-Claudius Gellrich Heinz Haferkamp Ingo Nolte 《International journal of molecular sciences》2015,16(6):13287-13301
Degradable implant material for bone remodeling that corresponds to the physiological stability of bone has still not been developed. Promising degradable materials with good mechanical properties are magnesium and magnesium alloys. However, excessive gas production due to corrosion can lower the biocompatibility. In the present study we used the polymer coating polycaprolactone (PCL), intended to lower the corrosion rate of magnesium. Additionally, improvement of implant geometry can increase bone remodeling. Porous structures are known to support vessel ingrowth and thus increase osseointegration. With the selective laser melting (SLM) process, defined open porous structures can be created. Recently, highly reactive magnesium has also been processed by SLM. We performed studies with a flat magnesium layer and with porous magnesium implants coated with polymers. The SLM produced magnesium was compared with the titanium alloy TiAl6V4, as titanium is already established for the SLM-process. For testing the biocompatibility, we used primary murine osteoblasts. Results showed a reduced corrosion rate and good biocompatibility of the SLM produced magnesium with PCL coating. 相似文献
950.
Investigation of a 6‐MSA Synthase Gene Cluster in Aspergillus aculeatus Reveals 6‐MSA‐derived Aculinic Acid,Aculins A–B and Epi‐Aculin A 下载免费PDF全文
Dr. Lene M. Petersen Dr. Dorte K. Holm Assoc. Prof. Charlotte H. Gotfredsen Prof. Uffe H. Mortensen Assoc. Prof. Thomas O. Larsen 《Chembiochem : a European journal of chemical biology》2015,16(15):2200-2204
Aspergillus aculeatus, a filamentous fungus belonging to the Aspergillus clade Nigri, is an industrial workhorse in enzyme production. Recently we reported a number of secondary metabolites from this fungus; however, its genetic potential for the production of secondary metabolites is vast. In this study we identified a 6‐methylsalicylic acid (6‐MSA) synthase from A. aculeatus, and verified its functionality by episomal expression in A. aculeatus and heterologous expression in A. nidulans. Feeding studies with fully 13C‐labeled 6‐MSA revealed that 6‐MSA is incorporated into aculinic acid, which further incorporates into three compounds that we name aculins A and B, and epi‐aculin A, described here for the first time. Based on NMR data and bioinformatic studies we propose the structures of the compounds as well as a biosynthetic pathway leading to formation of aculins from 6‐MSA. 相似文献