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排序方式: 共有1002条查询结果,搜索用时 125 毫秒
1.
G Tufveson W Geelings M Broyer F P Brunner H Brynger S R Dykes J H Ehrich W Fassbinder G Rizzoni N H Selwood 《Nephrology, dialysis, transplantation》1989,4(3):161-171
This paper summarises the information given on the 1986 EDTA Registry centre questionnaire which was returned by 82% of the 2,065 known dialysis and transplant centres in 33 European countries. Information is given on the number of patients alive on haemodialysis according to the type of dialysis facilities available where the patient was receiving dialysis and the number of patients receiving special types of dialysis. The centre questionnaire also included questions on testing for HIV infection, serological evidence or symptoms of AIDS and the diagnosis of hepatitis B in patients and staff. The data given in response to these questions are presented together with data on the involvement of dietitians and social workers in the treatment of patients with end stage renal failure. Finally, information on transplant activity in Europe and the treatment policies of transplanting centres is provided. 相似文献
2.
Four groups of piglets were used to test the use of pericardium and periosteum as free grafts in the repair of full thickness cervical tracheal defects. Pericardium provided an airtight, rapidly healing graft, but did not give sufficient structural rigidity to prevent narrowing and growth failure at the graft site. Composite grafts of pericardium and periosteum were also unsatisfactory, in that the periosteum failed to produce enough bone to prevent collapse of the graft. Since previous studies have shown that periosteal grafts result in good bone formation when applied alone or as an extramucosal support, it is concluded that the osteogenic potential is dependent on the available blood supply and speed of revascularization. It appears that the presence of pericardium in the composite grafts may have inhibited this property. 相似文献
3.
The purpose of this study was to determine the conditions for optimum synergistic efficacy of the two-drug combination of trimetrexate and 5-fluorouracil. Synergistic cell killing of Chinese hamster ovary cells in these clonogenic survival assays was observed only when the cells had been exposed to trimetrexate (25 microM) for 2 to 4 h prior to 5-fluorouracil exposure (either 125 or 250 microM). The schedule dependence of the observed synergy in vitro was closely linked to trimetrexate-induced changes in cellular 5-phosphoribosyl 1-pyrophosphate (PRPP) pools. Exposure to 25 microM trimetrexate induced increases in PRPP pools to 398% and 761% of control values at 2 and 4 h, respectively. Methotrexate (20 microM) also increased Chinese hamster ovary cell PRPP content in a time-dependent fashion to values of 280 and 511% of control after 2 and 4 h of drug exposure. Previous in vivo studies demonstrated a modest degree of therapeutic synergy between trimetrexate and 5-fluorouracil against P388 leukemia. Our in vitro results suggested that the degree of synergy seen in vivo could be increased with appropriate schedule changes. Mice were implanted i.p. with 10(6) P388 leukemia cells on Day 0 and were treated with trimetrexate (every 3 h for eight injections; Days 1, 5, and 9) and 5-fluorouracil (Days 1, 5, and 9) as single agents or in combination on one of two schedules; 5-fluorouracil was administered with either the first or the last of the eight trimetrexate doses on Days 1, 5, and 9. Both treatment regimens demonstrated therapeutic synergy but, as predicted from the in vitro data, the "5-fluorouracil last" was superior to the "5-fluorouracil first" sequence. Treatment with the optimal doses on the "5-fluorouracil last" sequence (trimetrexate, 31; 5-fluorouracil, 33 mg/kg/injection) produced an increased life span of 183% and a net reduction in tumor cell burden of 6.7 logs compared with a 111% increased life span (net reduction in tumor burden of 2.6 logs) produced by the most active of the single agents, 5-fluorouracil. Thus the efficacy of the combination of trimetrexate with 5-fluorouracil was sequence and time dependent both in vitro and in vivo. The synergy, observed in vitro and probably in vivo, was linked to a trimetrexate-induced elevation of intracellular PRPP, thus facilitating the production of 5-fluoropyrimidine nucleotides. These data are similar to the sequence and schedule dependency of the methotrexate/5-fluorouracil combination with important differences.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
4.
A functional hippocampus is required for trace fear conditioning, which involves learning the association of a tone and shock that are separated over time. Young and aged rats received 10 trace conditioning trials. Twenty-four hours later, rats were tested for fear to the tone in a novel chamber by measuring freezing. The results showed significantly lower levels of freezing in aged rats as compared with young rats, which provides evidence of age-related memory impairments. Pseudorandom conditioning groups showed low levels of freezing, indicative of no associative memory. Age-related memory deficits were not found with delay conditioning, which suggests no age-related sensory-motor deficits. These data suggest that aging hinders the ability of the hippocampus to process information separated over time. 相似文献
5.
Retrospective analysis of 27 factors in 80 neonates with necrotizing enterocolitis has enabled us to identify three factors that appear to be of prognostic statistical significance, namely blood pH, platelet count, and the presence of congenital defects. All three factors may be assessed objectively at the time of admission of the patient. Using these factors we have estimated a "probability of death" score for each patient and a high-risk group of neonates has been identified. 相似文献
6.
Amy E. Lawrence Justin T. Huntington Kate Savoie Michael Dykes Jennifer H. Aldrink Holden Richards Gail E. Besner Brian Kenney Jeremy Fisher Peter C. Minneci Marc P. Michalsky 《Journal of pediatric surgery》2021,56(1):55-60
PurposeThe objective of this quality improvement (QI) initiative was to implement a standardized clinical treatment protocol for patients presenting with primary spontaneous pneumothorax (PSP) in order to decrease hospital length of stay (LOS), diagnostic radiation exposure, and related cost.MethodsBaseline data from patients admitted with PSP from January 1, 2016 to July 31, 2018 were compared to data from patients managed using a newly developed evidence-based treatment pathway from August 1, 2018 to December 31, 2019. Standard QI methodology was used to track results.ResultsFifty-six episodes of PSP were observed during the baseline period and 40 episodes of PSP following initiation of the PSP protocol. The average LOS decreased from 4.5 days to 2.9 days. Patients underwent an average of 8.8 X-rays per admission preintervention versus 5.9 postintervention. The rate of CT scans decreased from 45% to 15% (p = 0.002). There was no significant difference in the rates of 30-day recurrence between the preintervention (13%) and postintervention (10%) groups (p = 0.7). Average admission costs per patient decreased by $1322 after adoption of the pathway.ConclusionsAdoption of a standardized treatment protocol for PSP led to a reduction in LOS, diagnostic imaging utilization, and cost without increasing clinical recurrence.Type of studyQuality improvement.Level of evidenceLevel III. 相似文献
7.
A realist qualitative study to explore how low‐income pregnant women use Healthy Start food vouchers
Heather Ohly Nicola Crossland Fiona Dykes Nicola Lowe Victoria Hall Moran 《Maternal & child nutrition》2019,15(1)
Healthy Start is the UK government's food voucher programme for low‐income pregnant women and young children. It was introduced in 2006, but the impact of the programme on nutritional outcomes remains understudied. This study sought to explore potential outcomes of the Healthy Start programme (including intended and unintended outcomes) and develop explanations for how and why these outcomes might occur. A realist review preceded this study, in which programme theories were developed and tested using existing evidence. This qualitative study aimed to further refine and consolidate the programme theories from the realist review while remaining open to new and emerging theories (or hypotheses) about how low‐income pregnant women use Healthy Start vouchers. Semistructured interviews were conducted with 11 low‐income women from North West England, who received Healthy Start vouchers during pregnancy. A realist logic of analysis was applied to generate clear and transparent linkages between outcomes and explanations. The findings suggested that some women used the vouchers to improve their diets during pregnancy (intended outcome), whereas some women were diverted towards alternative or unintended outcomes. Women's circumstances, values, beliefs, and motivations influenced how they perceived and responded to the vouchers. This paper presents four evidence‐based programme theories to explain four contrasting (and potentially overlapping) outcomes: dietary improvements (theory refined from review), shared benefits (new theory), financial assistance (theory refined from review), and stockpiling formula (new theory). It considers how the Healthy Start programme could be improved, to increase the possibilities for low‐income women to experience the intended outcome of dietary improvements. 相似文献
8.
Johanna Sundqvist Mojgan Padyab Anna-Karin Hurtig Mehdi Ghazinour 《International journal of mental health》2018,47(1):3-25
This study aims to contribute to the knowledge of social support and its association with mental health amongst social workers and police officers in forced repatriation work of unaccompanied asylum-seeking refugee children. Nationally distributed surveys to social workers and police officers with and without experience of forced repatriation were used, measured by an abbreviated version of the Interview Schedule for Social Interaction (ISSI), and analyzed by univariate and multivariable regression models. Social workers in forced repatriation showed significantly poorer mental health than other social workers, but simultaneously relatively high access to social support. Irrespective of working with forced repatriation, police officers reported relatively high access to social support, but no difference in mental health. Furthermore, low levels of satisfaction with social interaction and close emotional support increased the odds of psychological disturbances for police officers in forced repatriation. Findings are discussed with special regard to the complexity of forced repatriation, particularly when children are the focus. 相似文献
9.
Divya Sharma Manila Lather Cherry L. Dykes Amita S. Dang Tridibes Adak Om P. Singh 《Parasitology research》2016,115(1):323-328
10.
Hyeoneui Kim Patricia C. Dykes Debra Thomas Linda A. Winfield Roberto A. Rocha 《Computers in biology and medicine》2011,(4):182-189
A small scale documentation analysis was conducted to explore the medical and surgical nursing content of the patient record at a large teaching hospital affiliated with Partners Healthcare System (PHS), in preparation for a computerized documentation system. Through this study, we identified a number of problems associated with the paper record that require resolution in the new computerized system, including elimination of documentation redundancy, areas where more structure is needed to properly capture data on nursing practice, and various design considerations to support a more complete and accurate documentation of nursing care. 相似文献