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P Lakshminarayana S Ibrahim P Venkataraman T Jagatheesan K G Kamala 《Indian pediatrics》1991,28(9):997-1001
We evaluated 50 mothers of children with Down syndrome attending Genetic Clinic of the Institute of Child Health and Hospital for Children, Madras, with special reference to their knowledge, belief and attitudes in the care of these children. After evaluation, they were educated individually and in groups with demonstration, picture cards and pamphlets, on the causation, expected health problems, developmental potential of Down syndrome and the ways and means to help the child to attain the maximum developmental potential. They were taught on preventive aspects of Down syndrome as well. Re-evaluation was done after three months, and considerable improvement was noted in the mother's knowledge, and attitude towards bringing up such a child. The mothers also showed an improvement in the skills in providing developmental enrichment to these children. Thus this study has formulated a programme in the management of such children, which can be practised on any population, anywhere, especially, in rural areas, and by less affluent folk, with poor educational background. 相似文献
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A modified method of treatment of congenital absence of the vagina with the use of amnion graft has been explained with illustrations. Follow-up of 20 patients treated with this method showed successful results without any postoperative cicatrization provided the marital relationship was started within 6-8 weeks. 相似文献
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Catherine Van Kerckhove Kamala Balakrishnan Joseph E. Levinson Martin G. Larson David N. Glass 《Human immunology》1988,22(4):227-233
Analysis of sex ratio in 301 siblings of 150 patients with early-onset pauciarticular juvenile rheumatoid arthritis revealed a male-to-female ratio of 1:2.00 in sibships with an HLA-B44+ proband, compared with a ratio of 1:1.05 in other sibships (G2 = 6.07, df = 1, p = 0.014). The siblings had a sex ratio of 1:0.8, when the HLA-B44 antigen was present in either parent but not transmitted to the proband. The capacity to distort the sex ratio was limited therefore to disease-associated HLA-B44 haplotypes. 相似文献
6.
S Kim U Boege S Krishnaswamy I Minor T J Smith M Luo D G Scraba M G Rossmann 《Virology》1990,175(1):176-190
The structure of Mengo virus had been determined from crystals grown in the presence of 100 mM phosphate buffer at pH 7.4. It is shown that Mengo virus is poorly infectious at the phosphate concentration similar to that in which it was crystallized. Maximal infectivity is achieved at 10 mM phosphate or less in physiological saline. The phosphate effect is ameliorated when the pH is lowered to 4.6. Although it has not been possible to study the crystal structure of the virus at low phosphate concentrations, it is shown that increasing the Cl- concentration at pH 6.2 or decreasing the pH to 4.6 causes substantial conformational changes confined to the "pit," a deep surface depression. These structural changes involve a movement of the "FMDV loop" (GH loop) in VP1, an ordering of the "VP3 loop" (GH loop in VP3) between 3176 and 3182, the displacement of a bound phosphate near the "FMDV loop" (GH loop in VP1), and movement of the carboxy terminus of VP2. The changes in conformation are correlated with the dissociation of the virion into pentamers at pH 6.2 and 150 mM Cl-. The localization of the conformational changes and the correlated role of the phosphate in controlling infectivity support the hypothesis that the "pit" is the receptor attachment site. 相似文献
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Rodent models of rheumatoid arthritis (RA) are useful tools to study the pathogenic process of RA. Among the most widely used models of RA are the streptococcal cell wall (SCW) arthritis model and the collagen-induced arthritis (CIA). Both innate and adaptive immune mechanisms are involved in these rodent models. While no models perfectly duplicate the condition of human RA, they are easily reproducible, well defined and have proven useful for development of new therapies for arthritis, as exemplified by cytokine blockade therapies. Besides SCW and CIA models, there are numerous others including transgenic models such as K/BxN, induced models such as adjuvant-induced and pristane models, and spontaneous models in certain mouse strains, that have been used to help understand some of the underlying mechanisms. This review provides an update and analysis of RA models in mice and rats. The array of models has provided rheumatologists and immunologists a means to understand the multifactorial disease in humans, to identify new drug targets, and to test new therapies. 相似文献
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Raghavan Krishnaswamy S. Gray David B. Scholz Thomas H. Nemeth Gregory A. Hussain Munir A. 《Pharmaceutical research》1996,13(12):1815-1820
Purpose. The objective was to evaluate the degradation profile of the elastase inhibitor DMP 777 and lay the foundation for formulation development.
Methods. The pKa was determined by potentiometric titration in mixed-aqueous solvents. The degradation kinetics were studied as a function of pH, buffer concentration, ionic strength, methanol concentration and temperature using a stability-indicating HPLC assay. The degradation products were identified by LC-MS, NMR, and by comparison with authentic samples.
Results. The pKa for the protonated piperazine nitrogen was estimated to be 7.04. The pH-rate profile is described by specific acid-, water-, and specific base-catalyzed pathways. The pH of maximum stability is in the range of 4 to 4.5 where water is the principal catalyst in the reaction. Buffer catalysis, primary salt effects and medium effects were observed. The proposed mechanism for acid catalyzed degradation is the rarely observed AAL1 which involves alkyl-nitrogen heterolysis. The driving force for the reaction appears to lie in the stability of the benzylic carbocation. The proposed mechanism for base catalyzed degradation is BAC2 which involves -lactam ring opening. The -lactam ring of DMP 777, a monolactam, appears to be as reactive as that in benzylpenicillin in the k
OH controlled region where a similar mechanism of hydrolysis should be operative. A contributing factor to this increased reactivity may lie in the reduced basicity of the -lactam nitrogen making it a good leaving group.
Conclusions. The degradation profile indicates that development of a solution dosage form of DMP 777 with adequate shelf-life stability at room temperature is feasible. 相似文献