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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.
Agustina Heredia-Martinez Guillermo Rosa-Diez Jorge R. Ferraris Anna-Karin Sohlenius-Sternbeck Carina Nihlen Annika Olsson Jon O. Lundberg Eddie Weitzberg Mattias Carlstrm Rafael T. Krmar 《Nutrients》2022,14(12)
Nitric oxide (NO) contributes to maintaining normal cardiovascular and renal function. This bioactive signalling molecule is generally formed enzymatically by NO synthase in the vascular endothelium. NO bioactivity can also be attributed to dietary intake of inorganic nitrate, which is abundant in our diet, especially in green leafy vegetables and beets. Ingested nitrate is reduced to nitrite by oral commensal bacteria and further to NO systemically. Previous studies have shown that dialysis, by means of removing nitrate and nitrite from the body, can reduce NO bioactivity. Hence, dietary intervention approaches aimed to boost the nitrate–nitrite–NO pathway may be of benefit in dialysis patients. The purpose of this study was to examine the kinetics of plasma nitrate and nitrite after a single intake of nitrate-rich concentrated beetroot juice (BJ) in adult hemodialysis (HD) patients and in age-matched healthy volunteers (HV). Eight HD patients and seven HV participated in this single center, randomized, single-blind, placebo-controlled, crossover study. Each participant received a sequential single administration of active BJ (70 mL, 400 mg nitrate) and placebo BJ (70 mL, 0 mg nitrate) in a random order separated by a washout period of seven days. For the kinetic analysis, blood samples were collected at different time-points before and up to 44 h after BJ intake. Compared with placebo, active BJ significantly increased plasma nitrate and nitrite levels both in HD patients and HV. The area under the curve and the maximal concentration of plasma nitrate, but not of nitrite, were significantly higher in HD patients as compared with HV. In both groups, active BJ ingestion did not affect blood pressure or plasma potassium levels. Both BJs were well tolerated in all participants with no adverse events reported. Our data provide useful information in planning dietary nitrate supplementation efficacy studies in patients with reduced NO bioactivity. 相似文献
9.
The mechanism of microsatellite instability is different in synchronous and metachronous colorectal cancer 总被引:1,自引:0,他引:1
Fernando?S.?Velayos Suk-Hwan?Lee Hongming?Qiu Sharon?Dykes Raymond?Yiu Jonathan?P.?Terdiman Julio?Garcia-AguilarEmail author 《Journal of gastrointestinal surgery》2005,9(3):329-335
MLH1 promoter hypermethylation has been described as the primary mechanism for high-frequency microsatellite instability (MSI-H)
in sporadic colorectal cancers (CRCs). The underlying molecular mechanism for microsatellite instability (MSI) in synchronous
and metachronous CRCs is not well described. A total of 33 metachronous CRC patients and 77 synchronous CRC patients were
identified from 2884 consecutive patients undergoing cancer surgery in an academic center. Evaluable tumors were tested for
MSI, immunohistochemistry for MLH1 and MSH2 protein expression, and hypermethylation of the MLH1 promoter. MSI-H tumors were
found in 12 (36%) metachronous CRC patients and 29 (38%) synchronous CRC patients. MSI-H metachronous CRC patients were younger
at index cancer diagnosis (64 vs. 76 years, P = 0.01) and more often were diagnosed before 50 years of age (4 of 12 vs. 0 of 29, P = 0.005). Loss of MLH1 expression associated with promoter hypermethylation was common in all patients, although more common
in MSI-H synchronous patients (50% metachronous vs. 83% synchronous, P = 0.03). Overall, MLH1 promoter hypermethylation was seen in 7 of 17 (41%) metachronous and 44 of 54 (81%) synchronous MSI-H
CRCs tested (P = 0.004). Although MSI occurred with equal frequency among patients with synchronous and metachronous CRCs, the underlying
mechanism for MSI was different. Observed differences in MLH1 promoter hypermethylation and patient characteristics suggest
most MSI-H synchronous CRCs in our population were sporadic in origin. In contrast, more MSI-H metachronous CRCs were associated
with patient and tumor characteristics suggestive of underlying hereditary nonpolyposis CRC.
Presented as a poster at Digestive Disease Week 2001, Atlanta, Georgia, May 20–23, 2001. 相似文献
10.
Larsson Anna-Karin Svalenius Elizabeth Crang Lundqvist Anita Dykes Anna-Karin 《Reproductive health》2010,7(1):1-10
A system to improve the management of emergencies during pregnancy, childbirth, infancy and childhood in a region of The Gambia (Brikama) with a population of approximately 250,000 has been developed. This was accomplished through formal partnership between the Gambian Ministry of Health, the World Health Organisation, Maternal Childhealth Advocacy International and the Advanced Life Support Group. Since October 2006, the hospital in Brikama has been renovated and equipped and more efficiently provided with emergency medicines. An emergency ambulance service now links the community with the hospital through a mobile telephone system. Health professionals from community to hospital have been trained in obstetric, neonatal and paediatric emergency management using skills' based education. The programme was evaluated in log books detailing individual resuscitations and by external assessment. The hospital now has constant water and electricity, a functioning operating theatre and emergency room; the maternity unit and children's wards have better emergency equipment and there is a more reliable supply of oxygen and emergency drugs, including misoprostol (for treating post partum haemorrhage) and magnesium sulphate (for severe pre-eclampsia). There is also a blood transfusion service. Countrywide, 217 doctors, nurses, and midwives have undergone accredited training in the provision of emergency maternal, newborn and child care, including for major trauma. 33 have received additional education through Generic Instructor Courses and 15 have reached full instructor status. 83 Traditional Birth Attendants and 48 Village Health Workers have been trained in the recognition and initial management of emergencies, including resuscitation of the newborn. Eleven and ten nurses underwent training in peri-operative nursing and anaesthetics respectively, to address the acute shortage required for emergency Caesarean section. Between May 2007 and March 2010, 109 patients, mostly pregnant mothers, were stabilised and transported to hospital by the new emergency ambulance service. 293 resuscitation attempts were documented in personal logbooks. A sustainable system for better managing emergencies has been established and is helping to negate the main obstacle impeding progress: the country's lack of available trained medical and nursing staff. However, insufficient attention was paid to improving staff morale and accommodation representing significant failings of the programme. 相似文献