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11.
We describe three families to highlight the variability of expression and penetrance that can occur in the craniosynostoses. In two of the families, gene carriers were only identified in retrospect by looking at photographs of other family members. In the third family, identical twins were initially thought to be discordant for sagittal craniosynostosis until early skull x rays were examined and both were found to be affected. The dilemmas faced when counselling these families are discussed. 相似文献
12.
Dimensions of cognitions associated with self-regulation of alcohol consumption were studied using a 22-item Reasons for Limiting Drinking (RLD) scale in a student survey of nine universities. Data on 2,482 drinkers were factor analyzed using several methods in split halves and the total sample. Four interpretable factors accounting for 39% of the common variance were consistently found. Based on core content, these subjective motivational factors were labeled self-control, upbringing, self-reform and performance. Reliability analysis was used to construct subscales to assess these factors. Subscales had adequate internal reliability (alphas = .66-.73) for brief research scales. Relationships between the RLD subscales and between these subscales and selected demographic, alcohol-consumption and problem indicators are summarized. Based on these results and an application in a prevention experiment with heavily drinking students, the niche for such "reasons" measures in participant screening and program evaluation is discussed. 相似文献
13.
Background
There is currently an unprecedented expressed need and demand for estimates of maternal mortality in developing countries. This has been stimulated in part by the creation of a Millennium Development Goal that will be judged partly on the basis of reductions in maternal mortality by 2015. 相似文献14.
15.
16.
The CTLA-4 gene region of chromosome 2q33 is linked to, and associated with, type 1 diabetes. Belgian Diabetes Registry 总被引:8,自引:1,他引:8
Nistico L; Buzzetti R; Pritchard LE; Van der Auwera B; Giovannini C; Bosi E; Larrad MT; Rios MS; Chow CC; Cockram CS; Jacobs K; Mijovic C; Bain SC; Barnett AH; Vandewalle CL; Schuit F; Gorus FK; Tosi R; Pozzilli P; Todd JA 《Human molecular genetics》1996,5(7):1075-1080
Susceptibility to autoimmune insulin-dependent (type 1) diabetes mellitus
is determined by a combination of environmental and genetic factors, which
include variation in MHC genes on chromosome 6p21 (IDDM1) and the insulin
gene on chromosome 11p15 (IDDM2). However, linkage to IDDM1 and IDDM2
cannot explain the clustering of type 1 diabetes in families, and a role
for other genes is inferred. In the present report we describe linkage and
association of type 1 diabetes to the CTLA-4 gene (cytotoxic T lymphocyte
associated-4) on chromosome 2q33 (designated IDDM12). CTLA-4 is a strong
candidate gene for T cell- mediated autoimmune disease because it encodes a
T cell receptor that mediates T cell apoptosis and is a vital negative
regulator of T cell activation. In addition, we provide supporting evidence
that CTLA-4 is associated with susceptibility to Graves' disease, another
organ- specific autoimmune disease.
相似文献
17.
Pulmonary toxicity of trichloroethylene: induction of changes in surfactant phospholipids and phospholipase A2 activity in the mouse lung 总被引:2,自引:0,他引:2
J E Scott P G Forkert M Oulton M G Rasmusson S Temple M O Fraser S Whitefield 《Experimental and molecular pathology》1988,49(1):141-150
Trichloroethylene (TCE) is a common organic solvent in use as a dry cleaning agent as well as an inhalant anesthetic. Nevertheless the effects of this material on the pulmonary surfactant which prevents alveolar collapse at maximal expiration is not known. Therefore, we have examined the effect of TCE on the intra- and extracellular surfactant pools and the activity of phospholipase A2, an enzyme which controls the remodeling of phosphatidylcholine to dipalmitoylphosphatidylcholine, the primary constituent of the pulmonary surfactant. Male CD-1 mice were treated ip with 2500 or 3000 mg/kg TCE. Twenty-four hours later mice were anesthetized and the lungs lavaged. Mice were then killed, the lungs perfused and excised, and subcellular fractions including lamellar bodies prepared. Some lungs were prepared for ultrastructural examination. Phospholipase A2 was assayed in all subcellular fractions. Phospholipid was assayed in the lavage (extracellular surfactant) and the lamellar bodies (intracellular surfactant). TCE (2500 mg/kg) caused selective exfoliation of Clara cells. However, only the dose of 3000 mg/kg TCE produced a significant decrease in the intracellular surfactant phospholipid. Minimal changes occurred in the phospholipid profiles. Phospholipase A2 specific activity was significantly decreased at both dosages within the lung microsomal fraction. In addition after treatment with 3000 mg/kg TCE the enzyme activity in the lamellar body fraction was significantly increased. These data suggest that inhalation of TCE may damage the enzymes which are responsible for synthesizing the pulmonary surfactant resulting in lower amounts of surfactant being stored and available for secretion into the alveolus. 相似文献
18.
19.
C. S. Temple J. R. Bronk P. D. Bailey C. A. R. Boyd 《Pflügers Archiv : European journal of physiology》1995,430(5):825-829
The proton dependence of the transport of three labelled, hydrolysis-resistant synthetic dipeptides carrying a net charge of –1, 0 or +1 has been investigated in a brush border membrane vesicle preparation obtained from rat renal cortex. Cross-inhibition studies are consistent with the transport of all peptides studied being through a single system. The extent and time course of uptake in response to an inwardly directed electrochemical gradient of protons differed for each peptide. For the cationic peptide D-Phe-L-Lys this gradient did not stimulate the initial rate of uptake, while for the neutral dipeptide D-Phe-L-Ala and the anionic peptide D-Phe-L-Glu stimulation was observed. However, the effect on D-Phe-L-Glu was more marked than that on D-Phe-L-Ala and the proton activation differed for these two peptides. The calculated Hill coefficients for the two proton-dependent peptides were 1.14±0.16 and 2.15±0.10 for D-Phe-L-Ala and D-Phe-L-Glu, respectively, providing evidence that the stoichiometry of proton: peptide cotransport is different for each peptide (01, 11 and 21 for D-Phe-L-Lys, D-Phe-L-Ala and D-Phe-L-Glu respectively); studies on energetics are compatible with this conclusion. The physiological and molecular implications of this model are discussed, as are the applicability of the conclusions to secondary active transport systems more generally. 相似文献
20.