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141.
The health of migrants in the UK and their access to healthcare is of considerable policy interest. There is evidence of ethnic inequalities in health and access to and use of healthcare but insufficient consideration of the importance of birth abroad and length of residence in the UK. This study examines indicators of health status, behaviour and healthcare use among mothers of infants in the Millennium Cohort Study, according to whether born in the UK or abroad, individual ethnic grouping, and length of residence. Our findings show there are both positive and negative health indicators associated with ethnicity, birth abroad, and length of residence and presenting results on a single factor in isolation could lead to a misinterpretation of associations. For mothers ethnicity has an important relationship with most health indicators independent of country of birth, length of residence and socio-demographic circumstances. Once adjusted for ethnicity and socio-demographic variables, association with birth abroad disappears for most health outcomes suggesting that there may not be an independent migrant penalty in health. There is a linear trend in decreasing health status with increasing length of residence but no independent association between length of residence and healthcare use. This suggests that while there are continuing barriers to good health for migrants in the receiving society as shown in other studies, factors important for one health outcome may not apply to another. Our findings challenge linear acculturation models for migrants’ health in showing that a linear trend in improving socio-economic circumstances for mothers in some ethnic groups is not always associated with better health outcomes or changes in health behaviour. Our results point to a need for a comprehensive collection of information and analysis for all categories of migrants for understanding patterns of and factors underlying health and use of healthcare. 相似文献
142.
Developmental changes in rabbit juxtamedullary proximal convoluted tubule bicarbonate permeability 总被引:1,自引:0,他引:1
The bicarbonate transport rate in neonatal rabbit juxtamedullary proximal convoluted tubules (JMPCT) is lower than that in adults. The reduced rate of transport could be due to a decrease in active bicarbonate transport or an increase in the passive permeability of the tubule to bicarbonate. The present in vitro microperfusion study directly measured the bicarbonate permeability of neonatal and adult JMPCT. Bicarbonate permeability was measured at both slow and fast perfusion rates to simulate the neonatal and adult proximal tubule flow rates, respectively. At 38 degrees C in tubules perfused at 3 nL/min, bicarbonate permeability was 0.29 +/- 0.11 x 10(-5) cm/s in neonates and 1.70 +/- 0.49 x 10(-5) cm/s in adult PCT (p less than 0.05). At a perfusion rate of 10 nL/min, bicarbonate permeability was 0.11 +/- 0.27 x 10(-5) cm/s in neonatal PCT and 2.31 +/- 0.15 x 10(-5) cm/s in adult PCT (p less than 0.05). These results demonstrate that bicarbonate permeability in neonatal JMPCT is significantly lower than that in adult JMPCT. Thus, the lower rate of bicarbonate transport in neonatal PCT is entirely due to a lower rate of active bicarbonate transport. 相似文献
143.
Kevin F. Quigley 《Health, risk & society》2005,7(3):267-291
This paper considers the manner and extent to which the media and public opinion influenced the US government's and the UK government's reaction to the Y2K computer bug. The data concerning Y2K come largely from primary and secondary government documents and newspaper articles and public opinion polls from the period as well as semi-structured interviews conducted with civil servants, representatives from the IT sector, and IT journalists. The paper concludes that during the early phases of Y2K planning there was anxiety among a professional elite, which included the media, the legislatures, and private industry, and this anxiety influenced the timing and magnitude of both governments' responses. With respect to public opinion, however, the governments were more concerned about shaping it rather than following it. Both governments raised the profile of Y2K as a strategy to minimize the impact of the bug in a complex and interdependent infrastructure. After having raised awareness and anxiety levels for over a year, however, the US government, in particular, was worried that it had done too good a job, and that public overreaction became a distinct possibility. They therefore embarked on a strategy of bringing public anxiety down. As New Year's Day 2000 approached, the governments' Y2K operations were no longer in line with public perception about the risk, but in light of the potential consequences of a public overreaction, this deviation seemed acceptable. 相似文献
144.
We have evaluated the feasibility of using polyanhydride disks containing hydrophobic antiproliferative agents for controlled drug release after glaucoma filtration surgery. Taxol and VP-16 were the most potent inhibitors of fibroblast proliferation tested, with ID50s of 3 ng/mL and 200 ng/mL, respectively. In vitro release of taxol occurred at concentrations exceeding its ID50 for at least 100 days; VP-16 was released for 31 days. The media into which the drugs were released were able to inhibit fibroblast proliferation in vitro, indicating that the bioactivity of the drugs withstood incorporation into, and release from, the polyanhydride. Polyanhydride disks containing taxol and VP-16 merit testing in animal models of glaucoma filtration surgery. 相似文献
145.
A Mr 92,000 metalloprotease, originally observed in neutrophils, has been found to be secreted by various normal and malignant cells of fibroblastic, hematopoietic, and epithelial origin. The responsiveness of the various cell types to the tumor promoter phorbol ester (phorbol myristate acetate) to secrete this enzyme and a corresponding Mr 72,000 gelatinase has been determined using gelatin zymograms. The latent zymogen form of the Mr 92,000 enzyme has been purified from phorbol myristate acetate-stimulated HT1080 human fibrosarcoma cells using sequential gelatin-Sepharose affinity chromatography and gel filtration. Selective elution from gelatin-Sepharose allows for a distinct separation of the Mr 92,000 gelatinase from the Mr 72,000 gelatinase. A fraction of the tumor cell derived latent Mr 92,000 enzyme is isolated as an apparent complex with human tissue inhibitor of metalloproteases, which is partially dissociated in sodium dodecyl sulfate and completely dissociated upon reduction of disulfide bonds and upon p-aminophenylmercuric acetate treatment. Organomercurial treatment rapidly allows for autoactivation of the proenzyme to active Mr 83,000 and Mr 75,000 species. At physiological pH, the enzyme rapidly degrades gelatin into small fragments and slowly cleaves native type V collagen at an apparent single site. Native type IV collagen is degraded to a much lesser extent. The NH2-terminal amino acid sequence of the Mr 92,000 proenzyme has been determined and is distinct from the Mr 72,000 gelatinase/type IV collagenase which is constitutively produced by fibroblasts. The Mr 92,000 enzyme is also immunologically distinct from the Mr 72,000 enzyme but immunologically cross-reactive with the neutrophil, high molecular weight gelatinase. The Mr 92,000 enzyme constitutes a distinct member of the matrix metalloprotease family. Its substrate specificity implies a broad physiological role, acting on basement membrane type V collagen as well as on denatured (gelatinized) collagens and thus may be involved in the invasive and migratory phenotype of human cells. 相似文献
146.
Seven eyes of six patients with glaucoma developed a flat anterior chamber, hypotony, and choroidal detachment two to 26 months after technically uncomplicated trabeculectomy. No signs warranting immediate surgical intervention, such as wound or bleb leakage, contact between cornea and lens, or massive choroidal detachments touching in the midvitreous cavity were found on initial examination. After treatment with topical corticosteroids and cycloplegic eyedrops, five of seven eyes showed marked clinical improvement within one month. The two remaining eyes eventually returned to normal anterior chamber depth, but required repeat filtration surgery for intraocular pressure control. 相似文献
147.
An in-vitro morphological study of Q-switched neodymium/YAG laser trabeculotomy. 总被引:2,自引:2,他引:0 下载免费PDF全文
S Venkatesh W R Lee S Guthrie F R Cruickshank W S Foulds R J Quigley R T Bailey 《The British journal of ophthalmology》1986,70(2):89-96
Laser trabeculotomies produced by directing a pulsed neodymium/YAG laser beam at specimens of human anterior chamber angle obtained post mortem or after enucleation were studied by light microscopy and by scanning and transmission electron microscopy to assess the dimensions of the openings created in the trabecular meshwork, their penetrance to the canal of Schlemm, and the extent or absence of laser induced cellular damage in immediately adjacent tissue. A pulse duration of 40-50 ns at energy levels of around 30 mJ was used and the laser cavity carefully tuned to give a Gaussian spatial mode pattern. Openings in the trabecular meshwork typically of 100 microns in diameter and penetrating through to the canal of Schlemm could be regularly created with only minimal damage to adjacent tissue as judged by transmission electron microscopy. The information so gained may be useful in determining the parameters required for successful laser trabeculotomy as a treatment for primary open-angle glaucoma. 相似文献
148.
James A. Reilly Jr. MD Curtis F. Forst MA Eamonn M. M. Quigley MD Layton F. Rikkers MD 《Digestive diseases and sciences》1990,35(6):781-786
The effects of portal hypertension on gastric motor function were investigated using the rat staged portal vein ligation model. Gastric emptying of liquids and solids was studied separately following meals labeled with 51Cr or 99Tc by whole stomach scintillation counting. Portal hypertension was consistently established in experimental rats (splenic pulp pressure: mean +/- SEM, portal hypertension versus control, 16.8 +/- 0.7 vs 11.8 +/- 0.7 mm Hg, P less than 0.0001). Although liquids were emptied in an exponential manner and solids in a linear fashion, gastric emptying of both meals was more rapid in the experimental rats. Ten minutes after the liquid meal, more than 50% of the meal had emptied from the stomachs of portal hypertensive rats while only one third of the meal had cleared in the control group (P less than 0.02). Gastric emptying of the solid meal was significantly accelerated in experimental rats at 60 and 120 min (percent meal remaining: portal hypertension versus control, 41.9 +/- 4.0 vs 55.4 +/- 3.5 and 21.5 +/- 4.9 vs 32.6 +/- 4.3, P less than 0.05). Stomachs of portal hypertensive animals were heavier (P less than 0.009) and histologic examination revealed submucosal edema. Thus, a possible mechanism of the disrupted gastric motor function in portal hypertension is decreased gastric wall compliance secondary to edema. 相似文献
149.
Selective effects of experimental glaucoma on axonal transport by retinal ganglion cells to the dorsal lateral geniculate nucleus. 总被引:4,自引:0,他引:4
L Dandona A Hendrickson H A Quigley 《Investigative ophthalmology & visual science》1991,32(5):1593-1599
Rapid-phase axonal transport to the dorsal lateral geniculate nucleus (dLGN) was determined autoradiographically in seven macaque monkey eyes with chronic intraocular pressure (IOP) elevation, in four eyes with an acute IOP elevation, and in three eyes with normal IOP. The monkeys with chronic IOP elevation showed a greater decrease in radioactive labeling of the magnocellular layers of the dLGN than the parvocellular layers by qualitative examination. Grain counts in selected specimens confirmed that transport to the magnocellular layers was less than to the parvocellular layers in monkeys with chronic IOP elevation. This selectivity was present in mildly damaged specimens and increased with greater ganglion cell loss. In monkeys with acute IOP elevation, qualitative evaluation suggested no consistent difference in transport among the dLGN layers; one animal in this group had less transport to the parvocellular than to the magnocellular layers by grain counts. Starting in early stages of the disease, chronic experimental glaucoma causes preferential damage to the ganglion cells that project to the magnocellular layers of the dLGN. 相似文献
150.
Dr. Pierre Lachapelle Lucie Blain Michael G. Quigley Robert C. Polomeno Stéphane Molotchnikoff 《Documenta ophthalmologica. Advances in ophthalmology》1989,73(4):359-368
Acute administration of diphenylhydantoin (DPH) in rabbits produces a significant increase in the amplitude of the a-wave. A marked increase in the amplitude of the b-wave is also noted but the time course is slower than that for the a-wave. While in controls the oscillatory potential (OP) recordings essentially consist of three major types, recordings taken after DPH injection consist of one major OP (OP2), which appears to be a result of the fusion of the original OP2 with another OP produced by the DPH injection. A similar blend of OPs was also seen in ERGs recorded from three human subjects on DPH therapy. 相似文献