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BACKGROUND: Little is known about parental experience and decision making with regard to premature infants requiring intensive care in developing countries. We undertook this study to characterise parents' experience of physician counselling and their role in making life-support decisions for very low-birth-weight (VLBW) (birth weight < 1 501 g) infants born in South Africa's public-sector neonatal intensive care units (NICUs). METHODS: Parents of surviving VLBW infants treated in three Johannesburg-area public hospitals and attending follow-up clinics in August 2001 were interviewed regarding their experience of perinatal counselling on outcomes (pain, survival, disability), perception of actual and optimal decision making, and satisfaction with NICU communication. RESULTS: Parents of 51 infants were interviewed. Seventy-five per cent of parents reported antenatal counselling by physicians on at least one perinatal topic (severe disability, pain, death, finances or religious/moral considerations). The majority of parents (> 60%) who received counselling thought that these topics had been discussed adequately. Most parents reported that doctors had the primary decision-making role, either without consulting them (41%) or after consulting them (37%). Joint decision making was rare (14%). Parents wanted more input in life-support decisions than they reported being given. CONCLUSION: Counselling is not consistently provided in public-sector hospitals in Johannesburg. Parents of premature infants want a larger share in NICU decision making than they currently experience. Most parents were satisfied with communication later during their infant's hospitalisation. South Africa presents a unique opportunity to study the use of advanced medical technologies in a nation with marked disparities in access to care.  相似文献   
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In vitro transcorneal permeability studies are an important screening tool in drug development. The objective of this research is to examine the feasibility of using corneas isolated from preserved rabbit eyes as a model for permeability evaluation. Eyes from male New Zealand White rabbits were used immediately or were stored overnight in phosphate-buffered saline (PBS) or Hanks balanced salt solution (HBSS) over wet ice. Integrity of isolated corneas was evaluated by measuring the TEER and by determining the permeability of paracellular and transcellular markers. Active transport was assessed by measuring transcorneal permeability of selected amino acids. Esterase activity was estimated using p-nitrophenyl assay. In all cases, corneas from freshly enucleated eyes were compared to those isolated from the day-old preserved eyes. Transcellular and paracellular passive diffusion was not affected by the storage medium and observed to be similar in the fresh and preserved eye models. However, amino acid transporters demonstrated lower functional activity in corneas excised from eyes preserved in PBS. Moreover, preserved eyes displayed almost 1.5-fold lower esterase activity in the corneal tissue. Thus, corneas isolated from day-old eyes, preserved in HBSS, closely mimics freshly excised rabbit corneas in terms of both active and passive transport characteristics but possesses slightly reduced enzymatic activity. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99: 1921–1930, 2010  相似文献   
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The aqueous polymerisation of methyl methacrylate initiated by the chromate/arsenite system has been studied. It is observed that the polymerisation by the above redox system is catalysed by OH? though the parent reaction between chromate and arsenite is catalysed by H. It is also observed that traces of Cu2⊕ inhibit both the polymerization reaction as also the parent reaction. From these observations it is concluded (1) intermediate valency states of chromium has no initiating power in alkali solution and (2) the redox reaction between chromate and arsenite is a chain reaction involving single electron transfer and the intermediate As4⊕ thus produced is the initiating species.  相似文献   
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Gamma interferon (IFN-gamma) is an important mediator of endotoxin (lipopolysaccharide [LPS])-induced immune responses. However, the specific cell types that produce IFN-gamma in response to LPS and the cellular factors that regulate LPS-induced IFN-gamma production have not been fully determined. The present studies were undertaken to characterize the cell populations that produce IFN-gamma after LPS challenge in the spleens of mice and to determine the regulatory factors that modulate LPS-induced production of IFN-gamma. Our studies show that the levels of splenic IFN-gamma mRNA and protein production peak at 6 and 8 h, respectively, after systemic LPS challenge. Approximately 60% of IFN-gamma-producing cells are natural killer (NK) cells (CD3(-)DX5(+)) and 25% are NKT cells (CD3(+)DX5(+)). Most of the remaining IFN-gamma-producing cells are T cells (CD3(+)DX5(-)), macrophages, and dendritic cells. Functionally, interleukin-12 (IL-12) is the major IFN-gamma-stimulating factor after LPS challenge, with costimulation provided by IL-15, IL-18, and B7 proteins. IL-10 is a major inhibitor of LPS-induced IFN-gamma production. Unlike intact heat-killed gram-negative and gram-positive bacteria, the class II major histocompatibility complex did not play a functional role in LPS-induced IFN-gamma production. LPS is a potent stimulus for splenic IL-10, IL-12 p40, and IL-15 mRNA expression, whereas IL-12 p35 and IL-18 mRNAs, as well as B7 proteins, are constitutively expressed in the mouse spleen. Of the factors studied, IL-18 serves as the most potent costimulus with IL-12 for IFN-gamma production, followed by IL-15 and B7 proteins. These data demonstrate that NK cells and NKT cells are the most abundant IFN-gamma-producing cells in the mouse spleen after LPS challenge and that IL-10 and IL-12 are key functional regulators of LPS-induced IFN-gamma production.  相似文献   
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Thalassemics require regular blood transfusion therapy leading to iron overload in the body tissues, which is a major cause of morbidity and mortality in these patients. We hereby attempted to measure this iron overload by means of exfoliative cytology, a non-invasive and inexpensive technique. The aims and objectives of our study were: 1. To detect iron overload by oral exfoliative cytology using Perl’s Prussian blue stain in β-thalassemia major patients. 2. To correlate staining positivity with serum ferritin levels. Smears were obtained from buccal mucosa of 50 β-thalassemia major patients (who had taken more than 12 transfusions) and 25 healthy subjects of the same age group as controls. Smears were stained with Perl’s Prussian blue. Blood samples were taken from the study group for estimation of serum ferritin levels. Grading criteria were defined for assessing the Prussian blue positivity. Perl’s positivity was observed in 49 out of 50 of thalassemic patients (98%). 1 patient had Grade 0, 7 patients had Grade I, 5 had Grade II, 12 had Grade III, 14 had Grade IV while 11 patients had Grade V positivity. Spearman Rank’s Correlation Co-efficient was 0.38, signifying a weak positive correlation between positivity of buccal smears for Perl’s Prussian blue staining and respective serum ferritin levels. Perl’s Prussian blue staining of exfoliated cells from buccal mucosa can be used to assess iron overload in β-thalassemia major patients, as a screening as well as diagnostic tool. With the grading system we can give a semi-quantitative assessment of the same.  相似文献   
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Background: Over one-third of the world’s population is exposed to household air pollution (HAP) but the separate effects of cooking with solid fuel and kerosene on childhood mortality are unclear.Objectives: To evaluate the effects of both solid fuels and kerosene on neonatal (0-28 days) and child (29 days-59 months) mortality.Methods: We used Demographic and Health Surveys from 47 countries and calculated adjusted relative risks (aRR) using Poisson regression models.Results: The aRR of neonatal and child mortality in households exposed to solid fuels were 1.24 (95% CI: 1.14, 1.34) and 1.21 (95% CI: 1.12, 1.30), respectively, and the aRR for neonatal and child mortality in households exposed to kerosene were 1.34 (95% CI: 1.18, 1.52) and 1.12 (95% CI: 0.99, 1.27), controlling for individual, household, and country-level predictors of mortality.Conclusions: Kerosene should not be classified as a clean fuel. Neonates are at risk for mortality from exposure to solid fuels and kerosene.  相似文献   
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