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61.
Screening behavior of women after a false-positive mammogram   总被引:2,自引:0,他引:2  
Pisano  ED; Earp  J; Schell  M; Vokaty  K; Denham  A 《Radiology》1998,208(1):245
  相似文献   
62.
63.
It is the purpose of the study to report the frequency of parvovirus in children with a diagnosis of Diamond-Blackfan anaemia and to discuss the possible aetiological role of parvovirus in Diamond-Blackfan anaemia. We found parvovirus DNA in 3 of 11 bone marrow smears. Giant pronormoblasts showed low sensitivity (33%) and poor specificity (75%). The presence of giant pronormoblasts was associated with a very high myeloid: erythroid ratio, and may not be specific for parvovirus infection, but a feature of severely suppressed erythropoiesis. The three parvovirus-positive patients were the only children who experienced a remission, and who are free of medication. The seven surviving parvovirus-negative patients are all currently on steroid treatment.  相似文献   
64.
The aim of the study was to investigate the effect of a protein restricted diet on renal function and growth of children with chronic renal failure. In a multicentre prospective study 56 children (aged 2-18 years) with chronic renal failure were randomly assigned to the protein restricted (0.8-1.1 g/kg/day) or the control group. All children were followed up by the same paediatrician and dietitian. After a follow up period of three years there was no significant difference in glomerular filtration rate between children on a protein restricted diet and children of the control group. There was no significant difference in weight with respect to height and height SD score between the protein restricted and the control group. Compliance with the protein restricted diet, as indicated by the prospective diet diaries and the serum urea:creatinine ratio, was good. This study shows that children with chronic renal failure do not benefit from a protein restricted diet.  相似文献   
65.
The suitability of protein-coupled liposomes as drug carriers for brain specific targeting was investigated using albumin (BSA) and cationized albumin (CBSA), respectively, as model proteins. Liposomes coated with polyethylene glycol (sterically stabilized, PEG-liposomes) were prepared from phosphatidylcholine, cholesterol, and a PEG-derivatized phospholipid and covalently coupled to thiolated BSA or CBSA. Liposomes were loaded with carboxy-fluorescein and rhodamine-labeled dipalmitoyl-phosphatidylethanolamine as hydrophilic and lipophilic marker compounds, respectively. The interaction of these constructs with monolayers of porcine brain capillary endothelial cells (BCEC) and freshly isolated porcine brain capillaries was studied by means of fluorescence assays and confocal laser scanning fluorescence microscopy (CLSFM). In contrast to BSA, CBSA was rapidly taken up by cultured BCECs. BSA-coupled liposomes did not interact with endothelial cells, whereas CBSA-coupled liposomes bound to cellular surfaces and exhibited time dependently a high intracellular accumulation. CBSA-conjugated liposomes were also taken up by intact brain capillaries. Cellular uptake could be inhibited by free cationized albumin, phenylarsineoxide, nocodazole, and filipin, but not by dansylcadaverine, suggesting a caveolae-mediated incorporation process. Immunostaining demonstrated a high expression of caveolin in the capillary endothelium. In conclusion, liposomes coupled to CBSA are taken up into brain endothelium via an endocytotic pathway and may therefore be a suitable carrier for drug delivery to the brain.  相似文献   
66.
Dave Coyle  MED RNLD RMN CERT ED    Deborah Edwards  BSC HONS  MPHIL    Ben Hannigan  BA  HONS  MA  RGN  RMN  DPSN    Phillip Burnard  MSC  P  h D  RMN  RGN RNT  DIPN  CERT ED  Anne Fothergill  BSC  P  h D  PGCE  RMN  RGN 《Nursing & health sciences》2000,2(1):59-67
Abstract Six hundred and fourteen Community Psychiatric Nurses (CPNs) were surveyed to estimate the extent to which they used various coping strategies in order to reduce occupation-related stress. A questionnaire booklet, which included a number of validated measures and the Psychnurse methods of coping questionnaire, were used. 'Having a stable home life that was separate from work' and 'knowing that my life outside of work is healthy, enjoyable and worthwhile' were methods used most in order to cope with work-based stress. 'Through having team supervision' and 'by having confidential one to one supervision' were the methods used the least. The mean overall coping scores were significantly higher for females and those who felt that they had job security. Those people who scored higher on the coping test instrument were significantly more likely to be older and have worked within the field of community mental health for longer. The current drive towards clinical supervision promoted through policy initiatives, appears not to be supported by these findings. The implications for CPN services and for further study are highlighted.  相似文献   
67.

BACKGROUND AND PURPOSE

Pharmacological preconditioning (PPC) with mitochondrial ATP-sensitive K+ (mitoKATP) channel openers such as diazoxide, leads to cardioprotection against ischaemia. However, effects on Ca2+ homeostasis during PPC, particularly changes in Ca2+ channel activity, are poorly understood. We investigated the effects of PPC on cardiac L-type Ca2+ channels.

EXPERIMENTAL APPROACH

PPC was induced in isolated hearts and enzymatically dissociated cardiomyocytes from adult rats by preincubation with diazoxide. We measured reactive oxygen species (ROS) production and Ca2+ signals associated with action potentials using fluorescent probes, and L-type currents using a whole-cell patch-clamp technique. Levels of the α1c subunit of L-type channels in the cellular membrane were measured by Western blot.

KEY RESULTS

PPC was accompanied by a 50% reduction in α1c subunit levels, and by a reversible fall in L-type current amplitude and Ca2+ transients. These effects were prevented by the ROS scavenger N-acetyl-L-cysteine (NAC), or by the mitoKATP channel blocker 5-hydroxydecanoate (5-HD). PPC signficantly reduced infarct size, an effect blocked by NAC and 5-HD. Nifedipine also conferred protection against infarction when applied during the reperfusion period. Downregulation of the α1c subunit and Ca2+ channel function were prevented in part by the protease inhibitor leupeptin.

CONCLUSIONS AND IMPLICATIONS

PPC downregulated the α1c subunit, possibly through ROS. Downregulation involved increased degradation of the Ca2+ channel, which in turn reduced Ca2+ influx, which may attenuate Ca2+ overload during reperfusion.  相似文献   
68.
Collection of pluripotential hematopoietic stem cells by cytapheresis   总被引:1,自引:1,他引:1  
Lasky  LC; Ash  RC; Kersey  JH; Zanjani  ED; McCullough  J 《Blood》1982,59(4):822-827
Successful complete hematopoietic reconstitution (CHR) using nonleukemic peripheral stem cells (PSC) after marrow ablation has been reported in animals but not man. Previous studies of cytapheresis products from humans, as a prelude to use for CHR, have documented the presence of committed myeloid (CFU-GM) and erythroid (BFU-E) precursors. We have examined mononuclear cell (MNC) products collected on the Fenwal CS3000 Blood Cell Separator for these plus the more primitive mixed (granulo-, erythro-, mono-, and megakaryocytic) cell colony-forming units (CFU-GEMM) and for various lymphocytic subpopulations (LSP). One to two-hour products contained 36 +/- 7 CFU- GEMM/10(6) MNC (mean +/- SE, n = 8) or 490 +/- 131/ml product. This compared favorably with blood (23 +/- .4/10(6) MNC or 46 +/- 8/ml, n = 14) and bone marrow (146 +/- 58/10(6) MNC, n = 12). Collection efficiency for E-rosette-positive cells approximated that for total lymphocytes and was variable for other LSP. Recovery of CFU-GEMM after freezing in 10% dimethylsulfoxide at a controlled rate and storage in liquid N2 was 54% +/- 8% (n = 8). Cytapheresis collection of large numbers of pluripotent hematopoietic precursors and demonstration of adequate recovery of these after cryopreservation, both previously unreported, are significant steps toward eventual CHR using nonleukemic PSC.  相似文献   
69.
Policy Points
  • Several intergovernmental organizations (Organisation for Economic Co‐operation and Development, World Health Organization, United Nations) are urging countries to use well‐being indicators (e.g., life satisfaction) in addition to traditional economic indicators when making important policy decisions.
  • As the number of governments implementing this new approach grows, so does the need to continue evaluating the health and well‐being outcomes we might observe from policies aimed at improving life satisfaction.
  • The results of this study suggest that life satisfaction is a valuable target for policies aiming to enhance several indicators of psychosocial well‐being, health behaviors, and physical health outcomes.
ContextSeveral intergovernmental organizations (Organisation for Economic Co‐operation and Development, World Health Organization, United Nations) are urging countries to use well‐being indicators (e.g., life satisfaction) in addition to traditional economic indicators when making important policy decisions. As the number of governments implementing this new approach grows, so does the need to continue evaluating the health and well‐being outcomes we might observe from policies aimed at improving life satisfaction.MethodsWe evaluated whether positive change in life satisfaction (between t0;2006/2008 and t1;2010/2012) was associated with better outcomes on 35 indicators of physical, behavioral, and psychosocial health and well‐being (in t2;2014/2016). Data were from 12,998 participants in the University of Michigan''s Health and Retirement Study—a prospective and nationally representative cohort of US adults over age 50.FindingsParticipants with the highest (versus lowest) life satisfaction had better subsequent outcomes on some physical health indicators (lower risk of pain, physical functioning limitations, and mortality; lower number of chronic conditions; and higher self‐rated health) and health behaviors (lower risk of sleep problems and more frequent physical activity), and nearly all psychosocial indicators (higher positive affect, optimism, purpose in life, mastery, health mastery, financial mastery, and likelihood of living with spouse/partner; and lower depression, depressive symptoms, hopelessness, negative affect, perceived constraints, and loneliness) over the 4‐year follow‐up period. However, life satisfaction was not subsequently associated with many specific health conditions (i.e., diabetes, hypertension, stroke, cancer, heart disease, lung disease, arthritis, overweight/obesity, or cognitive impairment), other health behaviors (i.e., binge drinking or smoking), or frequency of contact with children, family, or friends.ConclusionsThese results suggest that life satisfaction is a valuable target for policies aiming to enhance several indicators of psychosocial well‐being, health behaviors, and physical health outcomes.  相似文献   
70.
The creation of an abdominal stoma is a common procedure performed as part of the treatment for many conditions. Common complications include poor stoma siting, high output, skin irritation, ischaemia, retraction, parastomal hernia and prolapse. An extremely rare stoma complication is parastomal evisceration. We present a case of a 48-year-old woman who presented to us with parastomal evisceration as a late complication of a transverse colostomy. It is the second case reported as acomplication of this procedure but the first that occurred after such a long postoperative period (almost 18 months).  相似文献   
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