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71.
72.
Radiograph-based methods were used to assess alveolar bone loss in 12 juvenile and 18 adult baboons (Papio hamadryas, sensu lato) living in the Awash National Park, Ethiopia. Alveolar bone loss, as measured from the cementoenamel junction to the alveolar crest, averaged about 1 mm in juveniles and about 1.5 mm in adults. Densitometry of alveolar bone from the radiographs provides a baseline for comparisons with other adult baboons. Periodontal disease surveys of baboon populations using such methods may identify potential etiological agents. Such knowledge may contribute to a better understanding of periodontal disease etiology in humans. © 1993 Wiley-Liss, Inc.  相似文献   
73.
Previous studies on the lipopigment from the livers of sheep affected with ceroid lipofuscinosis showed that the disease does not involve a defect in lipid metabolism or abnormal lipid peroxidation and that most of the lipopigment was proteinaceous. In this study, lipopigment was isolated from liver, kidney, pancreas, and brain of affected sheep without the use of proteolytic enzymes. Lipopigment from all tissues was two-thirds protein. Modified silver staining after sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed a major band of Mr = 14,800, heterogeneous material between Mr = 5,000 and 9,000, and a major band of Mr = 3,500. These compounds did not stain for RNA or carbohydrate and were digested by a nuclease-free protease as expected for protein. They are not normal lysosomal proteins. Lipopigment levels of dolichol, ubiquinone, and cholesterol were consistent with the lipopigment being protein-enriched lysosome-derived cytosomes. The presence of the Mr = 3,500 proteins in whole affected tissue homogenates distinguished them from homogenates of normal tissues. It was concluded that low Mr proteins are specifically stored in ovine ceroid lipofuscinosis and that the ceroid lipofuscinoses may result from inherited defects in lysosomal protein catabolism.  相似文献   
74.
We summarize work based on electrophoretic screening for protein variation within and between primate species. We consider serum proteins—albumins, haptoglobins, transferrins—and red cell proteins—carbonic anhydrases, hemoglobins. Using hemoglobin, cytochrome-c, and fibrinopeptides as examples, we discuss the value of using molecular data, i.e. protein structures, in evolutionary studies and in primatology.  相似文献   
75.
The use of a presterilized, disposable, mesh-supported membrane envelope in the Watson Marlow Kiil dialyser results in a 12% improvement in urea and creatinine clearance. Priming volume, uptake volume, and ultrafiltration rate are unchanged. Residual blood volume remains small. Blood flow resistance is increased. The envelope therefore offers considerable advantages over conventional assembly for dialysis with a blood pump.  相似文献   
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Background

Annotations that describe the function of sequences are enormously important to researchers during laboratory investigations and when making computational inferences. However, there has been little investigation into the data quality of sequence function annotations. Here we have developed a new method of estimating the error rate of curated sequence annotations, and applied this to the Gene Ontology (GO) sequence database (GOSeqLite). This method involved artificially adding errors to sequence annotations at known rates, and used regression to model the impact on the precision of annotations based on BLAST matched sequences.

Results

We estimated the error rate of curated GO sequence annotations in the GOSeqLite database (March 2006) at between 28% and 30%. Annotations made without use of sequence similarity based methods (non-ISS) had an estimated error rate of between 13% and 18%. Annotations made with the use of sequence similarity methodology (ISS) had an estimated error rate of 49%.

Conclusion

While the overall error rate is reasonably low, it would be prudent to treat all ISS annotations with caution. Electronic annotators that use ISS annotations as the basis of predictions are likely to have higher false prediction rates, and for this reason designers of these systems should consider avoiding ISS annotations where possible. Electronic annotators that use ISS annotations to make predictions should be viewed sceptically. We recommend that curators thoroughly review ISS annotations before accepting them as valid. Overall, users of curated sequence annotations from the GO database should feel assured that they are using a comparatively high quality source of information.  相似文献   
78.

Background  

Malaria parasite secretes various proteins in infected RBC for its growth and survival. Thus identification of these secretory proteins is important for developing vaccine/drug against malaria. The existing motif-based methods have got limited success due to lack of universal motif in all secretory proteins of malaria parasite.  相似文献   
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Background  

One of the major challenges in post-genomic era is to provide functional annotations for large number of proteins arising from genome sequencing projects. The function of many proteins depends on their interaction with small molecules or ligands. ATP is one such important ligand that plays critical role as a coenzyme in the functionality of many proteins. There is a need to develop method for identifying ATP interacting residues in a ATP binding proteins (ABPs), in order to understand mechanism of protein-ligands interaction.  相似文献   
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