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1.
The major histocompatibility (B) complex of a distinct commercial pure White Leghorn chicken line was characterized using serological, biochemical and restriction fragment length polymorphism (RFLP) typing. Line B chickens displayed a high recombination frequency within the B complex. Three recombinant haplo-types were identified. The influence of these haplotypes was determined in relation to the haplotypes Bl9 and B21 on their resistance to Marek's disease (MD) in an experimental infection with the virus. Offspring of sires with a recombinant haplotype in combination with B19 or B21, and dams, which were homozygous B19/B19 or B21/B21 were infected. The B type of the offspring had a significant effect upon survival. Animals with B complex types B21/B21, B134/B21 and B234/B21 were relatively resistant to MD (24–32% mortality), whereas B19/B19 birds were highly susceptible (68% mortality). Animals with a recombinant halpotype B19r21 (B-G21, B-F19) were equally susceptible to MD as birds with the complete B19 haplotype. In contrast to earlier publications, resistance was not inherited as a dominant trait. Apparently, B19 was associated with a dominant susceptibility. The gene(s) associated with the B complex and involved in resistance to MD were localized within the B-F/B-L region. However, the association with a presumably non-coding subregion of B-G could not be excluded.  相似文献   
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In the field of arterial vascular reconstructions there is an increasing need for functional small-diameter artificial grafts (inner diameter < 6mm). When autologous replacement vessels are not available, for example because of the bad condition of the vascular system in the patient, the surgeon has no other alternative than to implant a synthetic polymer-based vessel. After implantation the initial major problem concerning these vessels is the almost immediate occlusion, due to blood coagulation and platelet deposition, under the relatively low flow conditions. As the search for the perfect bio-inert polymer has not revealed a material with suitable properties for this application, improved performance of small-diameter artificial blood vessels is now being sought in the biological field. The poor blood-compatibility of an artificial vascular graft is not simply because of its coagulation-stimulating or platelet-activating properties, but more due to its inability to actively participate in the prevention of blood coagulation and platelet deposition. As these functions are naturally performed by endothelial cells, the utilization of these cells seems inevitable for the construction of a functional small-diameter artificial blood vessels. This review describes the current status of the use of endothelial cells to improve the performance of artificial vascular prostheses.  相似文献   
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Background

Facilitation is a promising implementation intervention, which requires theory-informed evaluation. This paper presents an exemplar of a multi-country realist process evaluation that was embedded in the first international randomised controlled trial evaluating two types of facilitation for implementing urinary continence care recommendations. We aimed to uncover what worked (and did not work), for whom, how, why and in what circumstances during the process of implementing the facilitation interventions in practice.

Methods

This realist process evaluation included theory formulation, theory testing and refining. Data were collected in 24 care home sites across four European countries. Data were collected over four time points using multiple qualitative methods: observation (372 h), interviews with staff (n?=?357), residents (n?=?152), next of kin (n?=?109) and other stakeholders (n?=?128), supplemented by facilitator activity logs. A combined inductive and deductive data analysis process focused on realist theory refinement and testing.

Results

The content and approach of the two facilitation programmes prompted variable opportunities to align and realign support with the needs and expectations of facilitators and homes. This influenced their level of confidence in fulfilling the facilitator role and ability to deliver the intervention as planned. The success of intervention implementation was largely dependent on whether sites prioritised their involvement in both the study and the facilitation programme. In contexts where the study was prioritised (including release of resources) and where managers and staff support was sustained, this prompted collective engagement (as an attitude and action). Internal facilitators’ (IF) personal characteristics and abilities, including personal and formal authority, in combination with a supportive environment prompted by managers triggered the potential for learning over time. Learning over time resulted in a sense of confidence and personal growth, and enactment of the facilitation role, which resulted in practice changes.

Conclusion

The scale and multi-country nature of this study provided a novel context to conduct one of the few trial embedded realist-informed process evaluations. In addition to providing an explanatory account of implementation processes, a conceptual platform for future facilitation research is presented. Finally, a realist-informed process evaluation framework is outlined, which could inform future research of this nature.

Trial registration

Current controlled trials ISRCTN11598502.
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This paper aims to explore farmers’ preferences for sheep or goats based on feeding practices, animal and flock performances and economic benefits of sheep and goats in different agro-ecological zones in Central Java, Indonesia. In total, 150 smallholder farmers were selected from three agro-ecological zones: the lowlands, the middle zone, and the uplands. Feeding and performance parameters were estimated through weekly farm visits and farm records, from September 2001 to August 2003. In the lowlands, small ruminants were fed mainly with field grass and crop residues, whereas in the middle zone and uplands feeds fed were mainly field grass and leaves. Sheep were given more opportunities to graze than goats, however, grazing was not a major component in the diets. In the lowlands and the middle zone the differences in feed intakes, ADG and reproductive performances between sheep and goats were small. In all zones, does had significantly larger litters than ewes. In the uplands, goats had a significantly higher DMI, grew slightly faster, and had a higher weaning rate than sheep. Consequently, in the uplands, the total economic benefits from goat flocks were 25% higher than from sheep flocks. The major differences in agro-ecological conditions that affect the choice for sheep or goats were the availability of cassava peels in the lowlands, favouring a choice for sheep, and the abundance of leaves in the middle zone and uplands, which favours keeping goats. The promotion of goats by the government, the family tradition of keeping sheep or goats, the preference for sacrificing sheep for religious festivities, and the high initial investment needed to buy goat breeding stock could be other important motives to keep sheep or goats. Sheep fattening based on rice bran supplementation could be a feasible innovation in the lowlands. In the middle zone and uplands goat breeding could make a positive contribution to rural livelihoods.  相似文献   
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Background

Health care practice needs to be underpinned by high quality research evidence, so that the best possible care can be delivered. However, evidence from research is not always utilised in practice. This study used the Promoting Action on Research Implementation in Health Services (PARIHS) framework as its theoretical underpinning to test whether two different approaches to facilitating implementation could affect the use of research evidence in practice.

Methods

A pragmatic clustered randomised controlled trial with embedded process and economic evaluation was used. The study took place in four European countries across 24 long-term nursing care sites, for people aged 60 years or more with documented urinary incontinence. In each country, sites were randomly allocated to standard dissemination, or one of two different types of facilitation. The primary outcome was the documented percentage compliance with the continence recommendations, assessed at baseline, then at 6, 12, 18, and 24 months after the intervention.Data were analysed using STATA15, multi-level mixed-effects linear regression models were fitted to scores for compliance with the continence recommendations, adjusting for clustering.

Results

Quantitative data were obtained from reviews of 2313 records. There were no significant differences in the primary outcome (documented compliance with continence recommendations) between study arms and all study arms improved over time.

Conclusions

This was the first cross European randomised controlled trial with embedded process evaluation that sought to test different methods of facilitation. There were no statistically significant differences in compliance with continence recommendations between the groups. It was not possible to identify whether different types and “doses” of facilitation were influential within very diverse contextual conditions. The process evaluation (Rycroft-Malone et al., Implementation Science. doi: 10.1186/s13012-018-0811-0) revealed the models of facilitation used were limited in their ability to overcome the influence of contextual factors.

Trial registration

Current Controlled Trials ISRCTN11598502. Date 4/2/10.The research leading to these results has received funding from the European Union’s Seventh Framework Programme (FP7/2007–2013) under grant agreement no. 223646.
  相似文献   
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Background

Medicinal plants are used by 80% of people from developing countries to fulfill their primary health needs, occupying a key position on plant research and medicine. Taking into account that, besides their pharmaceutical importance, these plants contribute greatly to ecosystems' stability, a continuous documentation and preservation of traditional knowledge is a priority. The objective of this study was to organize a database of medicinal plants including their applications and associated procedures in Canhane village, district of Massingir, province of Gaza, Mozambique.

Methods

In order to gather information about indigenous medicinal plants and to maximize the collection of local knowledge, eleven informants were selected taking into account the dimension of the site and the fact that the vegetation presents a great homogeneity. The data were collected through intensive structured and semi-structured interviews performed during field research. Taxonomical identification of plant species was based on field observations and herbarium collections.

Results

A total of 53 plant species have been reported, which were used to treat 50 different human health problems. More than half of the species were used for stomach and intestine related disturbances (including major diseases such as diarrhea and dysentery). Additionally, four species with therapeutic applications were reported for the first time, whose potential can further be exploited. The great majority of the identified species was also associated with beliefs and myths and/or used as food. In general, the community was conscientious and motivated about conservational issues and has adopted measures for the rational use of medicinal plants.

Conclusions

The ethnomedicinal use of plant species was documented in the Canhane village. The local community had a rich ethnobotanical knowledge and adopted sound management conservation practices. The data compiled in this study show the social importance of the surveyed plants being a contribution to the documentation of PGR at the national and regional level.  相似文献   
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