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991.
Li S Hassed S Mulvihill JJ Nair AK Hopcus DJ 《American journal of medical genetics. Part A》2004,(1):96-98
Ablepharon-macrostomia syndrome (AMS) is a rare condition reported to date in 13 patients worldwide. AMS is characterized by absent or short eyelids, absent eyebrows and eyelashes, macrostomia, and external ear abnormalities. Additional features include alopecia or sparse hair, hypoplastic malar region, redundant skin, rudimentary nipples, abnormal genitalia. While the AMS phenotype is well delineated in infants and children, clinical manifestations are rather poorly characterized in adulthood. Here, we report on an Italian woman who received a diagnosis of AMS at the age of 46 years after several surgical treatments. A clinical comparison between our patient and previously reported AMS cases aids in delineating the adult phenotype of AMS and further broadens the clinical spectrum of this condition. 相似文献
992.
Maternal HIV Infection: Parenting and Early Child Development 总被引:1,自引:1,他引:1
Black Maureen M.; Nair Prasanna; Harrington Donna 《Journal of pediatric psychology》1994,19(5):595-616
Examined whether support could offset the potential stress ofmaternal HIV infection with regard to parenting and early childdevelopment in two studies of low income, urban, drug-usingmothers of infants and toddlers. In one study, support was providedthrough home intervention; in the other, support was measuredthrough self-report. There were few differences in parentingand early child development related to maternal HIV infection.HIV+ mothers reported less child-related stress among theirtoddlers, more normative levels of child abuse potential following18 months of home intervention, and displayed more positiveinvolvement with their children. Results, interpreted from ecologicaltheory, suggest that although the early stages of maternal HIVinfection may have been too distal to influence the lives ofhigh-risk mothers of infants and toddlers, when differencesexisted, HIV+ mothers demonstrated more positive attitudes andbehaviors toward parenting and were more able to benefit fromhome intervention than HIV mothers. 相似文献
993.
Chethrappilly Reghunadhan Nair Marie Christine Richou Gilbert Clouet 《Macromolecular chemistry and physics.》1991,192(3):579-590
The concept of macro iniferter (MI) was applied to realize the synthesis of triblock copolymers of ethyl acrylate (EA) with styrene (St) or methyl methacrylate (MMA), with EA forming the end blocks. The syntheses involved 3 steps. Secondary amine terminated poly(ethyl acrylate) was synthesisted by polymerization of EA in presence of butyl-(2-mercaptoethyl)ammonium chloride as a functional chain-transfer agent. The macroamine so obtained was converted to the macrothiuram disulfide by reaction with CS2 and I2. Thermal polymerization of MMA or St in presence of this macroiniferter led to the respective triblock copolymers. The kinetics of polymerization of MMA and styrene using MI and two different chain lengths was done in limited concentration ranges. The kinetic parameters indicated that the iniferter action was not affected by the incorporation of the thiuram disulfide groups in the polymer backbone. Triblock copolymers of differing block lengths of hard and soft segments could be prepared by varying the chain length of the macroamine and the concentration of the iniferter in the reaction system. The copolymers were characterized by GPC analysis and spectral or elemental analyses. In the case of St, analysis showed formation of perfect triblocks, whereas for MMA, tendencies to form diblocks were observed on increasing the chain length of the iniferter-forming block. DSC analyses showed demixing of the soft EA block and the hard central blocks. 相似文献
994.
Absolute quantitation of Marek's disease virus genome copy number in chicken feather and lymphocyte samples using real-time PCR 总被引:3,自引:0,他引:3
Baigent SJ Petherbridge LJ Howes K Smith LP Currie RJ Nair VK 《Journal of virological methods》2005,123(1):53-64
A real-time PCR method was developed, optimised and validated, to enable quantitation of Marek's disease virus genomes as copy number per million host cells. The duplex PCR measured the virus meq gene and host ovotransferrin gene in a single reaction enabling correction for differences in amount of sample DNA added. A bacterial artificial chromosome (BAC) clone of the virus genome, and a plasmid (pGEM-T-ovo) bearing a fragment of the chicken ovotransferrin gene, were used to quantify virus and host genomes respectively. This sensitive and reproducible assay was established initially using chicken lymphocyte DNA, then adapted for feather tip DNA by inclusion of bovine serum albumin in the reaction to overcome inhibition by melanin. The principal advantages are: (1) determination of absolute virus genome copy number enabling meaningful comparison between samples; (2) expression of copy number per million cells, allowing direct correlation with plaque assays; (3) using BAC-cloned whole virus genome as a standard potentially enables any virus gene to be used as the PCR target. This is the first report of quantitation of MDV genomes in feather tips, and application of this assay could significantly further our understanding of pathogenesis, spread, diagnosis, genetic resistance and vaccinal control of Marek's disease. 相似文献
995.
Novel elastomeric nonporous polyurethane membranes were synthesised with differing hard segment contents for evaluation as possible islet encapsulation matrices. Physico-chemical properties of these membranes were reported earlier by authors and have been found suitable for immunoisolation. In the present study, membranes were evaluated for their in vitro biocompatibility. Membranes T1, T4, T5 and T6 did not show toxicity in direct cell contact study towards L929 fibroblasts. However, T2 and T3 were found cytotoxic and were excluded from further testing. NIH3T3 cells when exposed to leach out products of T4, T5 and T6 showed no cytotoxicity, while T1 decreased cellular viability as confirmed by MTT assay. T4 and T5 alone were seen to be compatible with mouse islets while T6 was incompatible to the mouse islets. Digital image analysis (DIA) studies showed intact morphology of islets cultured on the T4 and T5 with viability (88.4 and 91% respectively) comparable to islets on tissue culture polystyrene (TCPS) control. Islets on T4 and T5 also retained their functionality, as judged by insulin secretion in response to in vitro glucose challenge (16.0 mM). These studies point out the crucial role of surface free energy and hydrophilicity in deciding compatibility of polyurethane membranes with islets of Langerhans. Studies indicate that polyurethane membranes T4 and T5 could be potential candidates for islet immunoisolation. 相似文献
996.
Effect of terfenadine on the bronchoconstriction induced by ultrasonically nebulized distilled water 总被引:2,自引:0,他引:2
Ultrasonically nebulized distilled water (UNDW) has been shown to induce bronchoconstriction in asthmatics. The proposed mechanism is through changes in osmolarity of the airway fluids and subsequent release of mediators from airway mast cells. We investigated whether terfenadine has a protective effect on UNDW challenges. Twelve mild-to-moderate asthmatics responded to screening a methacholine and UNDW challenge. For four hours after the ingestion of 0, 120, and 240 mg of terfenadine pulmonary responses were performed, followed by a UNDW challenge. Nine of 12 subjects dropped 20% after 120 mg and after 240 mg. There was a suggestion of a protective effect at 120 mg (P = .054), which was significant at 240 mg (P = .012) when the areas under the dose-response curves were compared. Bronchoconstriction induced by UNDW may in part be caused by histamine release and was attenuated by an oral antihistamine. 相似文献
997.
The effect of age on methacholine response 总被引:4,自引:0,他引:4
R J Hopp A Bewtra N M Nair R G Townley 《The Journal of allergy and clinical immunology》1985,76(4):609-613
Bronchial reactivity to inhaled methacholine exists in subjects with asthma but may occur in subjects with allergic rhinitis, chronic lung diseases, and during respiratory infections. In the absence of these factors, we found that age also has a significant effect on the methacholine response. One hundred forty-eight subjects, 5 to 76 years of age, were studied as normal control subjects in a natural history of asthma study. The methacholine response was measured by standard techniques. The analysis demonstrated that age had a significant effect on the methacholine response. In addition to known factors influencing the results of methacholine inhalation, young and older subjects may exhibit bronchial responses that may falsely suggest hyperreactive airway disease. 相似文献
998.
Black Maureen M.; Gerson Linda F.; Freeland Claire A. B.; Nair Prasanna; Rubin John S.; Hutcheson Jacqueline J. 《Journal of pediatric psychology》1988,13(3):423-433
The language, developmental status, and characteristics of mother-infantinteraction in a group of infants with a history of recurrentotitis media were compared to those of a healthy control group(mean age of infants = 14.66 months). Both groups received theirwell child and medical care at a university-affiliated inner-cityprimary pediatric clinic. An easily administered language screeninginstrument, the Early Language Milestones Scale (ELM), was highlysensitive and specific in the early identification of languagedelay. While the majority of infants exhibited language anddevelopmental scores within normal limits, 28% of the infantswith a history of otitis media had language and developmentaldelays by 18 months of age. Exposure to an enriched linguisticenvironment through maternal cognitive growth-fostering behaviorobserved during a mother-infant play session was positivelyassociated with higher scores on an infant assessment of cognitivedevelopment. These results lend support to a rational-constructionisttheoretical interpretation that through linguistic enrichmentinfants may compensate for periods of hearing loss. 相似文献
999.
C Okada R J Hopp H Miyagawa H Sugiyama N M Nair A K Bewtra R G Townley 《International archives of allergy and immunology》1992,97(3):181-186
In this double-blind crossover study we evaluated the effect of terfenadine on the rise in neutrophil chemotactic activity (NCA) and eosinophil chemotactic activity (ECA) in serum induced by platelet-activating factor (PAF) inhalation in 8 asthmatics. Additionally, we examined the direct effect of terfenadine on neutrophil chemotaxis in vitro in 7 allergic subjects. NCA and ECA in serum after PAF inhalation and neutrophil chemotaxis were measured using a modified Boyden chamber method. An initial elevation of NCA after PAF inhalation was inhibited by terfenadine, but the effect was diminished after subsequent PAF inhalations. Terfenadine showed no effect on ECA. In vitro PAF- and fMLP-induced neutrophil chemotaxis were significantly inhibited by terfenadine. These results suggest that terfenadine may have antiallergic properties in addition to its H1 receptor blockade. 相似文献
1000.
Tardive dyskinesia: a two-year follow-up study 总被引:2,自引:0,他引:2