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Viswambharan Sarasan Ryan Cripps Marcaret M. Ramsay Caroline Atherton Monica McMichen Grace Prendergast Jennifer K. Rowntree 《In vitro cellular & developmental biology. Plant》2006,42(3):206-214
Summary
In vitro techniques have found increasing use in the conservation of threatened plants in recent years and this trend is likely to
continue as more species face risk of extinction. The Micropropagation Unit at Royal Botanic Gardens, Kew, UK (RBG Kew) has
an extensive collection of in vitro plants including many threatened species from throughout the world. The long history of the unit and the range of plants
cultured have enabled considerable expertise to be amassed in identifying the problems and developing experimental strategies
for propagation and conservation of threatened plants. While a large body of knowledge is available on the in vitro culture of plants, there are limited publications relating to threatened plant conservation. This review highlights the progress
in in vitro culture and conservation of threatened plants in the past decade (1995–2005) and suggests future research directions. Works
on non-threatened plants are also included wherever methods have applications in rare plant conservation. Recalcitrant plant
materials collected from the wild or ex situ collections are difficult to grow in culture. Different methods of sterilization and other treatments to establish clean
material for culture initiation are reviewed. Application of different culture methods for multiplication, and use of unconventional
materials for rooting and transplantation are reviewed. As the available plant material for culture initiation is scarce and
in many cases associated with inherent problems such as low viability and endogenous contamination, reliable protocols on
multiplication, rooting, and storage methods are very important. In this context, photoautotrophic micropropagation has the
potential for development as a routine method for the in vitro conservation of endangered plants. Long-term storage of material in culture is challenging and the potential applications
of cryopreservation are significant in this area. Future conservation biotechnology research and its applications must be
aimed at conserving highly threatened, mainly endemic, plants from conservation hotspots. 相似文献
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Tom P. Moorhouse Cecilia A. L. Dahlsj? Sandra E. Baker Neil C. D'Cruze David W. Macdonald 《PloS one》2015,10(10)
Tourism accounts for 9% of global GDP and comprises 1.1 billion tourist arrivals per annum. Visits to wildlife tourist attractions (WTAs) may account for 20–40% of global tourism, but no studies have audited the diversity of WTAs and their impacts on the conservation status and welfare of subject animals. We scored these impacts for 24 types of WTA, visited by 3.6–6 million tourists per year, and compared our scores to tourists’ feedback on TripAdvisor. Six WTA types (impacting 1,500–13,000 individual animals) had net positive conservation/welfare impacts, but 14 (120,000–340,000 individuals) had negative conservation impacts and 18 (230,000–550,000 individuals) had negative welfare impacts. Despite these figures only 7.8% of all tourist feedback on these WTAs was negative due to conservation/welfare concerns. We demonstrate that WTAs have substantial negative effects that are unrecognised by the majority of tourists, suggesting an urgent need for tourist education and regulation of WTAs worldwide. 相似文献
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Jiaoyang Lu Taotao Jiao Yanmei Li Ying Liu Yanan Wang Yatian Wang Minhua Zheng Xuefeng Lu 《PloS one》2015,10(3)
Background
The emerging submucosal tunneling and endoscopic resection (STER) technique provides definitive histological diagnosis as well as a therapeutic method for the gastric submucosal tumors (SMTs). We aim to present our experience and discuss key technical issues of STER.Methods
45 patients with gastric SMTs arising from MP received STER. First, a mucosal incision was made 3cm proximal to the tumour, a submucosal tunnel was subsequently built from the incision to the tumor. The tumor was gradually exposed and dissected from surrounding tissue and retrieved from the tunnel. The initial mucosal incision was closed by metal clips. For SMTs in the gastric fundus near cardia, the submucosal tunnel was built from lower esophagus, through the angle of His, to the tumor for resection.Results
STER was successfully performed in 43 patients; the other two were converted to surgery. Mean operating time was 79.3min (range 45–150min). Mean tumor size was 1.4cm (range 0.5–5cm). Of the total 47 resected SMTs, 36 were GISTs, 10 were leiomyomas and 1 was schwannoma. Complete resection was achieved in all patients. Intra-procedural peumoperitoneum occurred in 3 cases because of iatrogenic perforation, no special treatment was given. 7 patients presented with mild abdominal pain/distention and fever were given antibotics. No severe post-operative complication happened. No tumor recurrence occurred in the median 11 month follow-up period.Conclusion
Based on short-term follow-up observation, STER is a feasible, safe and minimally invasive method for the diagnosis and treatment of small (<3cm) SMTs in gastric body, antrum and proximal cardia. 相似文献10.
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《Journal of Biomedical Engineering》1981,3(4):329-330
Tools for Living is a concept which regards a technical aid for a disabled individual as being no different in principle from a tool which allows a normal individual to carry out a task for which his intrinsic biological equipment is inadequate.Acceptance of this concept would change the status, mechanism for provision and attitude towards technical aids, in a direction which would lower the barriers against personal acceptance, particularly in the elderly. It is forecast that the production of ‘tools’ specifically devised to compensate for the performance decrements in the elderly could become an important new branch of industry. 相似文献
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The uniformitarian principle is one of the most important foundations of all dendro- and paleo-sciences. Without it, no inferences about the past can be made. However, the use of this principle in our community is not consistent and partially incorrect, with the main confusion relating to the understanding of the “uniformitarian principle” as somehow implying a stable relationship between climate and tree growth. To solve this, we look briefly at the history of the term, show how we teach this principle in our textbooks, give some examples of incorrect applications of this principle in the recent literature and close with a simple, logical and straightforward interpretation of this principle to the dendro-community. Applying the principle of aggregate tree growth we show that instable climate-growth relationships and the “no-analogue problem” are not a violation of the uniformitarian principle, but rather reflect our incomplete understanding of tree growth processes. Simply stated: The “uniformitarian principle” is an a priori assumption of spatial and temporal invariance of law’s describing nature’s processes. Applied to the dendro-sciences it means that the principle of aggregate tree growth is valid in time and space. 相似文献
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Francesca Foti Stefano Sdoia Deny Menghini Stefano Vicari Laura Petrosini Fabio Ferlazzo 《PloS one》2015,10(11)
Effective task switching is supported by the inhibition of the just executed task, so that potential interference from previously executed tasks is adaptively counteracted. This inhibitory mechanism, named Backward Inhibition (BI), has been inferred from the finding that switching back to a recently executed task (A-B-A task sequence) is harder than switching back to a less recently executed task (C-B-A task sequence). Despite the fact that BI effects do impact performance on everyday life activities, up to now it is still not clear whether the BI represents an amodal and material-independent process or whether it interacts with the task material. To address this issue, a group of individuals with Williams syndrome (WS) characterized by specific difficulties in maintaining and processing visuo-spatial, but not verbal, information, and a mental age- and gender-matched group of typically developing (TD) children were subjected to three task-switching experiments requiring verbal or visuo-spatial material to be processed. Results showed that individuals with WS exhibited a normal BI effect during verbal task-switching, but a clear deficit during visuo-spatial task-switching. Overall, our findings demonstrating that the BI is a material-specific process have important implications for theoretical models of cognitive control and its architecture. 相似文献
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《The Western journal of medicine》1970,112(3):83-88
This Fifth Progress Report is being printed in three parts in California Medicine. Following the appearance of Part III the report will be bound in a pamphlet which may be ordered at $1 a copy from 693 Sutter Publications, Inc., 693 Sutter Street, San Francisco, California 94102. 相似文献
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《The Western journal of medicine》1970,112(2):66-69
This Fifth Progress Report is to be printed in three parts in California Medicine. Following the appearance of Part III the report will be bound in a pamphlet which may be ordered at $1 a copy from 693 Sutter Publications, Inc., 693 Sutter Street, San Francisco, California 94102. 相似文献