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81.
The distribution of complex carbohydrates has been investigated at the light and electron microscope levels in sweat glands of normal subjects and patients with Hurler's or Hunter's disease. Normal sweat glands examined with a battery of light microscopic histochemical methods revealed sulphated complex carbohydrate in secretory granules of the dark cells. These granules lacked affinity for dialysed iron (DI) at the light and electron microscope levels. The DI method demonstrated acid complex carbohydrates ultrastructurally on the surface of the intercellular canaliculi and central lumen in normal sweat glands. DI-reactive acidic material, presumably of mucopolysaccharide nature, surrounded and extended between collagen bundles in the stroma of normal skin, but was absent from the band which ensheathed the sweat gland and consisted of individual rather than bundled collagen fibrils. DI-reactive mucopolysaccharide lined and partially filled vacuoles of dark cells showing a laminar distribution in vacuoles of clear cells in sweat glands of a Hunter patient. The DI method also visualized mucopolysaccharide distributed throughout vacuoles in fibroblasts of this patient. DI-reactive acid material covered the luminal surface of the sweat gland, coated collagen bundles in the stroma and spared the periglandular collagenous sheath in skin from Hurler and Hunter patients as in that from normal controls. Acid phosphatase was localized ultrastructually in vacuoles and nearby cytoplasm and on plasmalemmae of clear cells, dark cells and myoepithelial cells of sweat glands from Hurler and Hunter patients. Vacuoles of dermal fibroblasts and Schwann cells in these specimens also exhibited strong acid phosphatase activity. 相似文献
82.
L J Arthur W M Moncrieff W Milburn P S Bayliss J Heath 《BMJ (Clinical research ed.)》1976,1(6022):1363-1366
A scheme for dealing with cases of non-accidental injury in children in the Derby clinical area has been operating since 1971. A stable team of doctors, policemen, and social workers deal with each case. The parents are told at once that battering is suspected, and the police and social services department co-operate closely in establishing the facts, supporting the family, and protecting the child. A psychiatric assessment of the parents may help social workers decide on the long-term care of the child, and the forensic physician is invaluable if the case has to go to court. The team has made three recommendations about prevention and management of these cases: a specialist social service team should be set up to deal with these children and regain the skills and knowledge lost when children''s departments were abolished in 1971; babies should be routinely weighed naked in infant welfare clinics; and juvenile courts should be able to order a psychiatric report on the parents in care proceedings. 相似文献
83.
R.P. Herd L. Ko S.E. Weisbrode D.D. Heath 《International journal for parasitology》1984,14(2):141-149
Herd R. P., Ko L., Weisbrode S. E. and Heath D. D. 1984. Sequential morphologic changes in adult Echinococcus granulosus during complement-mediated lysis in vitro. International Journal for Parasltology14:141–149. Sequential changes (5,10, 20, 30,40, 50 min, 1, 2, 3, 4, 5, 6, 7, 8, h) were observed by light, scanning and transmission electron microscopy after 38-day-old adult Echinococcus granulosus were exposed to 50% guinea pig serum in vitro. Early changes within 3 h included contraction of worms, fusion of microtriehes, vacuolization and vesiculization of the distal cytoplasm, followed by rupture of vesicles leading to erosion and loss of the distal cytoplasm. This was most marked in the terminal proglottid but ultimately there was complete erosion of the distal cytoplasm of all proglottids and the scolex. After 3 h there was loss of definition of organelles, apparent edema of the perinuclear cytoplasm and, in some instances, rupture of the circular muscle layer with extrusion of parenchyma. Adult tape-worms exposed to heat-inactivated complement showed none of these changes. Lysis and death of the parasite was attributed to osmotic changes subsequent to the formation of trans-membrane channels induced by complement-mediated attack of the tegument after activation of the alternate pathway by factors present in the cestode tegument. 相似文献
84.
85.
D.J. Heath 《Journal of theoretical biology》1977,64(2):363-373
Current theories explain simultaneous hermaphroditism by the advantage it gives to organisms which are widely dispersed or sluggish, resulting in a low frequency of reproductive contacts. It is difficult to see why hermaphroditism is not more widespread unless there is some counterbalancing disadvantage.It is suggested that hermaphrodites suffer an energetic cost because they maintain two reproductive systems and a cost due to the reduced number or viability of offspring which may result from accidental self-fertilization. These costs will result in a disadvantage to hermaphroditism (compared to gonochorism) when reproductive contacts are frequent. However, even in widely dispersed or sluggish organisms behavioural mechanisms may exist which increase the frequency of reproductive contacts, favouring gonochorism instead of hermaphroditism.It is argued that externally fertilizing species should as a rule be gonochoric and that species which brood their young may often be hermaphroditic. Hermaphroditism in species which form permanent male/female pairs in the breeding season could result in more zygotes being produced. However, where parental care of the young is important, it is suggested that gonochorism and sexual dimorphism may result in more progeny being reared. 相似文献
86.
The human aldose reductase gene maps to chromosome region 7q35 总被引:1,自引:0,他引:1
Alexander Graham Paul Heath John E. N. Morten Alexander F. Markham 《Human genetics》1991,86(5):509-514
Summary The human aldose reductase (AR) gene has been mapped to chromosome 7 using the polymerase chain reaction to specifically amplify the human AR sequence in hamster/human hybrid DNA and also in mouse/ human monochromosome hybrids. The assignment to chromosome 7 was confirmed by in situ hybridisation to human metaphase chromosomes using a novel, rapid hybridisation, method giving a regional localisation at 7q35. 相似文献
87.
Joel P. Heath H. Grant Gilchrist Ronald C. Ydenberg 《Proceedings. Biological sciences / The Royal Society》2010,277(1697):3179-3186
To maximize fitness, animals must respond to a variety of processes that operate at different rates or timescales. Appropriate decisions could therefore involve complex interactions among these processes. For example, eiders wintering in the arctic sea ice must consider locomotion and physiology of diving for benthic invertebrates, digestive processing rate and a nonlinear decrease in profitability of diving as currents increase over the tidal cycle. Using a multi-scale dynamic modelling approach and continuous field observations of individuals, we demonstrate that the strategy that maximizes long-term energy gain involves resting during the most profitable foraging period (slack currents). These counterintuitive foraging patterns are an adaptive trade-off between multiple overlapping rate processes and cannot be explained by classical rate-maximizing optimization theory, which only considers a single timescale and predicts a constant rate of foraging. By reducing foraging and instead digesting during slack currents, eiders structure their activity in order to maximize long-term energetic gain over an entire tide cycle. This study reveals how counterintuitive patterns and a complex functional response can result from a simple trade-off among several overlapping rate processes, emphasizing the necessity of a multi-scale approach for understanding adaptive routines in the wild and evaluating mechanisms in ecological time series. 相似文献
88.
89.
Joan K. Heath Murray C. Meikle Susan J. Atkinson John J. Reynolds 《Biochimica et Biophysica Acta (BBA)/General Subjects》1984,800(3):301-305
Unstimulated monolayer cultures of confluent rabbit periosteal fibroblasts synthesize a factor that stimulates bone resorption in vitro. Furthermore it stimulates rabbit chondrocytes and mouse osteoblasts to synthesize collagenase. The factor has no effect on dead bone in culture, and its activity on live bone is mediated principally by osteoclasts, since it is 75% inhibited by salmon calcitonin. Characterization of the factor by gel filtration and isoelectric focusing indicates an Mr in the range 15 000–25 000 and a pI corresponding to approx. pH 4.7. These biological and physicochemical properties are similar to those reported for a factor released by peripheral blood monocytes. However, whereas human monocyte factor in both the crude and partially-purified state exhibits interleukin-1 activity, crude and fractionated periosteal fibroblast-conditioned medium does not. This is the first report of a conditioned medium containing a molecule like the monocyte-factor which appears to have no interleukin 1 activity. The factor may be synthesized by a wide range of cell types, and could have an important role in mediating connective tissue degradation during both physiological and pathological resorption. 相似文献
90.
Jorim J. Tielbeek Sarah E. Medland Beben Benyamin Enda M. Byrne Andrew C. Heath Pamela A. F. Madden Nicholas G. Martin Naomi R. Wray Karin J. H. Verweij 《PloS one》2012,7(10)
Crime poses a major burden for society. The heterogeneous nature of criminal behavior makes it difficult to unravel its causes. Relatively little research has been conducted on the genetic influences of criminal behavior. The few twin and adoption studies that have been undertaken suggest that about half of the variance in antisocial behavior can be explained by genetic factors. In order to identify the specific common genetic variants underlying this behavior, we conduct the first genome-wide association study (GWAS) on adult antisocial behavior. Our sample comprised a community sample of 4816 individuals who had completed a self-report questionnaire. No genetic polymorphisms reached genome-wide significance for association with adult antisocial behavior. In addition, none of the traditional candidate genes can be confirmed in our study. While not genome-wide significant, the gene with the strongest association (p-value = 8.7×10−5) was DYRK1A, a gene previously related to abnormal brain development and mental retardation. Future studies should use larger, more homogeneous samples to disentangle the etiology of antisocial behavior. Biosocial criminological research allows a more empirically grounded understanding of criminal behavior, which could ultimately inform and improve current treatment strategies. 相似文献