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21.
GARSAIRSGART is crucial in studies of Down syndrome (DS)-related mental retardation due to its chromosomal location (21q22.1), involvement in de novo purine biosynthesis and over-expression in fetal DS brain postmortem samples. GARSAIRSGART regions important for structure–function were screened for mutations that might alter protein levels in DS patients. Mutation screening relied on multiplex/singleplex PCR-based amplification of genomic targets followed by amplicon size determination/fingerprinting. Serum protein samples were resolved by SDS-PAGE and immunoblotted with a GARS–AIRS–GART monoclonal antibody. No variation in amplicon size/fingerprints was observed in regions encoding the ATP-binding, active site residues of GARS, the structurally important glycine-rich loops of AIRS, substrate-binding, flexible and folate-binding loops of GART or the poly-adenylation signal sequences. The de novo occurrence or inheritance of large insertion/deletion/rearrangement-type mutations is therefore excluded. Immunoblots show presence of GARS–AIRS–GART protein in all patient samples, with no change in expression levels with respect to either sex or developmental age.  相似文献   
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The use of the Internet as a teaching tool continues to grow in popularity at colleges and universities. We consider, from the students’ perspective, the use of an Internet approach compared to a lecture and lab‐based approach for teaching an introductory course in statistical methods. We conducted a survey of introductory statistics students. Contradictory to what was hypothesized by the authors, they favoured keeping the lecture and lab‐based approach for teaching the class.  相似文献   
23.
Background and objectives: Pharmacists use PDAs for performing various activities related to their profession. The objective of this study was to examine pharmacists’ utilization pattern and interest in usage of personal digital assistants (PDAs) in various facets of health care. Methods: A cross‐sectional survey was conducted by distributing a pre‐validated 23‐item instrument to a convenience sample of pharmacists (n = 295) in the Houston area. Usage frequency (0 = never to 5 = frequently) and interest in future use (1 = extremely disinterested to 5 = extremely interested) of PDAs for various activities were evaluated and compared across pharmacy practice settings. Results: Most pharmacists reported maximum use of PDAs, as personal organizers (3.7 ± 1.8), in obtaining drug information (2.9 ± 1.8) and as medical calculators (2.6 ± 1.9). Similar results were obtained while evaluating interest of pharmacists who did not have PDAs and have never used PDAs for these three activities. Hospital pharmacists owned and used PDAs significantly (P < 0.05) more often than community pharmacists. Conclusions: Pharmacists used PDAs for basic functions in their profession role. Application of PDA technology in community pharmacy settings may result in its better adoption in both the settings.  相似文献   
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The aim of this study was to assess the diagnostic yield of the tumour markers carcinoembryonic antigen, carbohydrate antigen 15-3, carbohydrate antigen 19-9 and carbohydrate antigen 125, in serum and bronchoalveolar lavage fluid in a group of patients with bronchogenic carcinoma. Serum and bronchoalveolar lavage fluid samples were collected in a group of 90 patients with benign or malignant pulmonary diseases. After appropriate processing, tumour markers were determined by enzyme immunoassay. The diagnostic yields (sensitivity, specificity and predictive values) in each environment (serum and bronchoalveolar lavage fluid) were obtained by using "Receivers operating characteristic" curve. Determined individually, carcinoembryonic antigen, carbohydrate antigen 19-9 and carbohydrate antigen 125, showed the greatest diagnostic accuracy in bronchoalveolar lavage fluid. Carbohydrate antigen 15-3 did so in serum. Carcinoembryonic antigen was the most relevant marker in bronchoalveolar lavage fluid. For the factors evaluated in this study, determination of carcinoembryonic antigen, carbohydrate antigen 19-9 and carbohydrate antigen 125 in bronchoalveolar lavage fluid were clinically more useful markers in comparison with serum, although the latter may also be helpful in certain situations. Although there is no specific tumour marker for lung cancer, the combination of several can be used to diagnose most patients with lung cancer and also to rule out false positive and negative cases.  相似文献   
26.
This paper proposes a new methodology for checking conformance of the software architectural design of Learning Management System (LMS) to Learning Technology System Architecture (LTSA). In our approach, the architectural designing of LMS follows the formal modeling style of Acme. An ontology is built to represent the LTSA rules and the software architecture in Acme style. Conformity of the design with LTSA rules is tested by reasoning the ontology with the query language SPARQL. A Java-based plug-in system is introduced to implement functionalities like loading the elements of the architectural design into the ontology, mapping the architectural elements with LTSA elements, and performing the conformance test. The advantage of the proposed methodology is two-folded. First, it verifies an important software quality attribute – conformance to technical standard – at an early stage of development, like high-level design phase. Secondly, instead of the conventional manual checklist based approach of conformance testing, this methodology focuses on an automated way to finding the conformance level of the system under check.  相似文献   
27.
The aim of the present study was to evaluate the serum levels of lecithin cholesterol acyl transferase and lipoprotein cholesterol in hyperthyroid patients. The serum levels of total cholesterol and triacylglycerols were also determined in order to assess the lipid status of these patients. It was observed that serum content of total cholesterol (TC), low density lipoprotein cholesterol (LDL-C) and high density liproprotein cholesterol (HDL-C) were significantly lower (P<0.001) in these patients whereas serum triacylglycerols (Tg.) and very low density lipoprotein cholesterol (VLDL-C) (P>0.05) did not show any significant change as compared to control values. However, the serum level of lecithin cholesterol acyl transferase (LCAT) was significantly higher (P<0.001) in these patients. It is concluded that an increased LCAT activity plays a significant role in regulating lipoprotein cholesterol levels in hyperthyroid patients.  相似文献   
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The present work proposes a complementary pair of orthogonal triangular function (TF) sets derived from the well-known block pulse function (BPF) set. The operational matrices for integration in TF domain have been computed and their relation with the BPF domain integral operational matrix is shown. It has been established with illustration that the TF domain technique is more accurate than the BPF domain technique as far as integration is concerned, and it provides with a piecewise linear solution.As a further study, the newly proposed sets have been applied to the analysis of dynamic systems to prove the fact that it introduces less mean integral squared error (MISE) than the staircase solution obtained from BPF domain analysis, without any extra computational burden. Finally, a detailed study of the representational error has been made to estimate the upper bound of the MISE for the TF approximation of a function f(t) of Lebesgue measure.  相似文献   
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