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231.
Anna Tsing Shiho Satsuka for the Matsutake Worlds Research Group 《Economic botany》2008,62(3):244-253
Diverging Understandings of Forest Management in Matsutake Science. As high-value gourmet mushrooms, the matsutake complex of the genus Tricholoma has been the subject of extensive research. This article reviews two trajectories of matsutake research, showing how distinctive
regional nodes may develop within a cosmopolitan modern science. The global center of matsutake research is in Japan, where
problems of artificial cultivation and the “orchard-style” enhancement of production under forest conditions stimulate basic
research. U.S. Pacific Northwest research forms a contrasting regional node, with a focus on sustainable yields in the context
of timber production. Regional differences in research design and results point to the importance of distinctive scientific
legacies, in this case formed in relation to divergent histories of forest management. Attention to regional distinctions
in the framing of scientific problems is particularly important as scientific frameworks are exported to new places; for example,
both Japanese and American forms of matsutake science have been extended to China.
高価なグルメきのこであるマツタケとその近縁種群のTricholoma属は広範囲に渡る科学的研究の対象となってきた。本論では二つの地域特徴的なマツタケ研究の軌跡を概観し、文化的差異を超えて世界的に通用する近代科学においても地域固有の関心に応じて特徴のある知識が結節し発展することを示す。マツタケ研究の世界的な中心地である日本では人工増殖やマツタケを殖やすための「果樹園的」な山林作りへの関心が基礎研究の方向性に刺激を与えてきた。一方日本とは対照的に、米国北西岸州では木材の持続的産出に主眼をおいた山林管理の流れの中で研究が進んできた。こうした研究計画や結果的に得られる知識の違いは、地域ごとに特徴のある科学的遺産
- 本件の場合は森林管理の歴史が多様に枝分かれしていること - に注目することが重要であることを知らせてくれる。近年日本や米国で発展したマツタケ研究の方法や成果が中国での研究にも影響を与えているが、特に新しい研究の場を広げる場合には科学的な関心、問題がどのような枠組で組み立てられるか地域によって多様であることを考慮することが重要である。 相似文献
232.
Association between Apolipoprotein E genotype and cerebral palsy is not confirmed in a Caucasian population 总被引:1,自引:1,他引:0
McMichael GL Gibson CS Goldwater PN Haan EA Priest K Dekker GA MacLennan AH;South Australian Cerebral Palsy Research Group 《Human genetics》2008,124(4):411-416
Apolipoprotein E (APOE) plays a significant role in lipid metabolism and has been implicated in the growth and repair of injured
neurons. Two small studies have suggested an association between APOE genotype and cerebral palsy. We investigated if APOE
genotype is associated with an increased risk for cerebral palsy, influences the type of cerebral palsy or interacts with
prenatal viral infection to influence risk of cerebral palsy. The population-based case-control study comprised newborn screening
cards of 443 Caucasian patients with cerebral palsy and 883 Caucasian matched controls. APOE genotyping was performed on DNA
extracted from dried blood spots. Allelic and genotypic frequencies did not differ between cases and controls and combined
frequencies were 0.10 (ε2), 0.76 (ε3), 0.14 (ε4), 0.03 (ε2/ε2), 0.10 (ε2/ε3), 0.03 (ε2/ε4), 0.02 (ε4/ε4), 0.21 (ε3/ε4), 0.61
(ε3/ε3). APOE genotype was correlated with cerebral palsy, type of cerebral palsy, gestation at birth and the presence of
viral nucleic acids detected in previous work. Analysis by gestational age (all gestational ages, ≥37, 32–36 and <32 weeks)
and type of cerebral palsy (all types, diplegia, hemiplegia and quadriplegia) showed no association between APOE genotype
and cerebral palsy in this Caucasian population. An association between prenatal viral infection, APOE genotype and cerebral
palsy was not demonstrated. These results did not confirm an association between APOE genotype, cerebral palsy, type of cerebral
palsy and prenatal infection in a Caucasian population. Given the low frequency of APOE ε2 and some of the heterozygote and
homozygote combinations in this study, a larger study is assessing this further. 相似文献
233.
Jie SHEN * Dong Bao YU * Chinese Center for Disease Control Prevention China Division of Policy Study Information National Center for AIDS Prevention Control China 《Cell research》2005,(Z1)
EVOLUTION OF THE GOVERNMENT POLI- CIES Looking back 20 and more years, one could have hardly imagined that such great changes would have happened to the governmental policies on HIV/AIDS in China. In the earlier phase of the epidemic, laws and regulations were drafted based on the practices and experiences of preven- tion and control of other infectious diseases, such as isolation, quarantine and compulsory testing and examina- tions etc. When the HIV/AIDS epidemic was firstl… 相似文献
234.
Oliver Rivero-Arias Helen Campbell Alastair Gray Jeremy Fairbank Helen Frost James Wilson-MacDonald for the Spine Stabilisation Trial Group 《BMJ (Clinical research ed.)》2005,330(7502):1239
Objective To determine whether, from a health provider and patient perspective, surgical stabilisation of the spine is cost effective when compared with an intensive programme of rehabilitation in patients with chronic low back pain.Design Economic evaluation alongside a pragmatic randomised controlled trial.Setting Secondary care.Participants 349 patients randomised to surgery (n = 176) or to an intensive rehabilitation programme (n = 173) from 15 centres across the United Kingdom between June 1996 and February 2002.Main outcome measures Costs related to back pain and incurred by the NHS and patients up to 24 months after randomisation. Return to paid employment and total hours worked. Patient utility as estimated by using the EuroQol EQ-5D questionnaire at several time points and used to calculate quality adjusted life years (QALYs). Cost effectiveness was expressed as an incremental cost per QALY.Results At two years, 38 patients randomised to rehabilitation had received rehabilitation and surgery whereas just seven surgery patients had received both treatments. The mean total cost per patient was estimated to be £7830 (SD £5202) in the surgery group and £4526 (SD £4155) in the intensive rehabilitation arm, a significant difference of £3304 (95% confidence interval £2317 to £4291). Mean QALYs over the trial period were 1.004 (SD 0.405) in the surgery group and 0.936 (SD 0.431) in the intensive rehabilitation group, giving a non-significant difference of 0.068 (–0.020 to 0.156). The incremental cost effectiveness ratio was estimated to be £48 588 per QALY gained (–£279 883 to £372 406).Conclusion Two year follow-up data show that surgical stabilisation of the spine may not be a cost effective use of scarce healthcare resources. However, sensitivity analyses show that this could change—for example, if the proportion of rehabilitation patients requiring subsequent surgery continues to increase. 相似文献
235.
Stanislav Gorb 《仿生工程学报(英文版)》2004,(1)
1 IntroductionInthenaturemanyanimals ,suchas geckoes ,flies ,bees ,locustsandspiders ,haveamagicabilitytomoveorholdonvarioussurfaces roughorsmoothfloors ,wallsorceilings.Themechanism ,howtheani malsattachto ,holdonanddetachfromthesurfaces ,mayenlightenusonwall climbingrobotsformthefeetdesign .Therobotsaregreatlyindemandinvacuumcircumstance ,insurvivorsearchinginflown downbuildingandinpipelineinspectingandrepairing .Themechanismsmayalsoshowushowtodesignhighadap tivemanipulators.Thebionicfeetd… 相似文献
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近年来,植物遗传转化研究有了长足的发展。已经达到能够通过简单的遗传控制手段研究具有新表现型的植物,甚至达到进入商业化的程度。这些手段包括植物生物学的主要研究技术以及植物组织培养和树种改良的一些实用方法。尽管采用农瘤杆菌和鸟枪法等技术的植物遗传转化系统已经得到了广泛的应用,但是在如何开发具有能够得到控制表达的转基因高产植物方面,在如何使所得到的转基因植物远离遗传危害等方面,目前的转化系统遇到了极大的技术挑战。已经提出了各种各样的方法用于将新基因稳定地导入120多种不同植物的核基因组。本文将讨论这些遗传转化系统所需的生物学要求和实际应用方面的需求、基因转化和转基因表达的研究策略、遗传转化植物的鉴定以及转基因植物与大众的认可。本文将分为七个部分加以讨论:一、导言;二 、基因转化到细胞里的方法;三、植物遗传转化策略;四、植物遗传转化的鉴定;五、植物遗传转化的实际应用;六、转基因植物与环境;七、未来植物遗传转化的需求与发展方向。 相似文献
240.