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921.
GeConT: gene context analysis   总被引:5,自引:1,他引:4  
SUMMARY: The fact that adjacent genes in bacteria are often functionally related is widely known. GeConT (Gene Context Tool) is a web interface designed to visualize genome context of a gene or a group of genes and their orthologs in all the completely sequenced genomes. The graphical information of GeConT can be used to analyze genome annotation, functional ortholog identification or to verify the genomic context congruence of any set of genes that share a common property. AVAILABILITY: http://www.ibt.unam.mx/biocomputo/gecont.html  相似文献   
922.
Augmentative biological control of whiteflies using transplants   总被引:1,自引:0,他引:1  
Field studies showed that transplants can be used to move parasitoids into fields of commercially grown cantaloupe, Cucumis melo (Cucurbitaceae), and augment parasitism of sweet potato whitefly, Bemisia tabaci biotype B (= Bemisia argentifolii) (Homoptera: Aleyrodidae). Methods were developed to inoculate cantaloupe seedlings with newly imported Eretmocerus spp. (Hymenoptera: Aphelinidae), then transfer plants into both organic and conventional fields of cantaloupe in the desert growing region of southeastern California. Several obstacles to inoculating banker plants with an adequate number of parasitized whiteflies were overcome and numbers of parasitoids per transplant increased. In 1999 the use of banker plants was compared to a standard hand-release method and a no-release control in a replicated study at an organic farm. Augmentation through releases of parasitoids increased parasitism over that in the no-release controls (p <0.05). Banker plants increased the proportion of parasitized whiteflies more than the hand-release method (0.21 vs. 0.08). During a region-wide demonstration spring 2000, plots receiving banker plants significantly increased parasitism over paired control plots at seven commercial farms of cantaloupe. Parasitism in banker plant treated plots in 2000 was higher in organic fields (seasonal average =0.30) than conventional ones (seasonal average =0.06). Differences may be due to the use of imidacloprid, a systemic insecticide, in conventional fields for whitefly control. Over the 2-year study, however, releases of parasitoids did not consistently reduce densities of B. tabaci. Only in late season at some sites in 2000 were whitefly densities lower in release plots than paired controls. Most of the parasitoids recovered and identified from plots receiving parasitoids were the same as those released, Eretmocerus spp. (ex. Ethiopia M96076), and E. hayati(M95012, ex. Pakistan).  相似文献   
923.
The overall status of self-incompatibility, as assessed by the rate of capsule-set after self-pollination, was investigated in the genus Calibrachoa (Solanaceae). Thirty-two species were surveyed using a total of 655 individuals collected in 102 different native populations in Argentina, Brazil, Mexico, and Uruguay. The rate of capsule-set in 278 voucher specimens collected from the same native habitats was also measured to obtain additional information to assess the degree of self-(in)compatibility. Only one species, Calibrachoa parviflora, was self-compatible (SC, autogamous) and the other 31 species were found to be self-incompatible (SI). A mixed population (SI and SC individuals in the same population) was not found. The differentiation of C. parviflora as an autogamous species is associated with a successful occupation of different (riparian) habitats within a larger range of geographic distribution compared to the rest of the species in the principally SI genus of Calibrachoa.  相似文献   
924.
The stable propagation of a full-length transmissible gastroenteritis coronavirus (TGEV) cDNA in Escherichia coli cells as a bacterial artificial chromosome has been considerably improved by the insertion of an intron to disrupt a toxic region identified in the viral genome. The viral RNA was expressed in the cell nucleus under the control of the cytomegalovirus promoter and the intron was efficiently removed during translocation of this RNA to the cytoplasm. The insertion in two different positions allowed stable plasmid amplification for at least 200 generations. Infectious TGEV was efficiently recovered from cells transfected with the modified cDNAs.  相似文献   
925.
926.
We investigated the effects of cannabinoids on acetylcholine (ACh) or choline contractures in slow skeletal muscle fibers from Rana pipiens. Bundles of cruralis muscle fibers were incubated with the cannabinoid receptor 1 (CB1) agonist, arachidonylcyclopropylamide (ACPA), which diminished the maximum isometric tension by 10 % and the total tension by 5 % of the ACh contracture, and 40 and 22 % of the choline contracture, respectively. Preincubation with the CB1 antagonist, AM281, or with pertussis toxin (PTX) completely blocked the effect of ACPA on the ACh contracture. On the other hand, the decrease in choline contracture by ACPA was only partially blocked by AM281 (~16 % decrease), PTX (20 %), or by dantrolene (~46 %). Our results show that ACPA modulates ACh and choline contractures, and suggest that this effect involves the participation of CB1, the ACh receptor, and ?RyR in ACh contractures. For choline contractures, ACPA may also be acting through cannabinoid receptor-independent mechanisms.  相似文献   
927.
This article explores the interconnections among origin narratives, migration patterns and ritual authority in a Timor-Leste community. By recognising the dimension of rituals as sources of power, we analyse the different ways social actors negotiate their position in social space by either supporting or contesting the legitimacy of the ritual leaders. We suggest how, in a context with historical levels of high migration and immersed in rapid social change, precedence is not only challenged by modern ideals around individual rights and choices, but by the re-interpretation of mythical narratives and the access to ritual performance. The paper provides a discussion of the notion of narrative capital and shows how subordinated classes resulting from development policies from past state regimes articulate new forms of social mobility in the contemporary context of rural Timor-Leste.  相似文献   
928.

Introduction

Pain in elderly people is considered a major concern in nursing home facilities affecting between 49% and 83% of the residents. Progression of Alzheimer's Disease causes more communication difficulties in patients with advanced dementia and therefore more problems to understand even the most simple pain evaluation scales. Identification and implementation of appropriate pain management strategies depends on an adequate pain assessment.

Material and methods

The main objective of the study was to validate the Spanish version of the PAINAD Scale (PAINAD-Sp) and to assess its applicability in Spanish Geriatric Nursing Homes. The 20 patients diagnosed with severe dementia from a Geriatric Centre in Spain were observed by five observers with different professional profiles for 5 minutes to each participant, and PAINAD-Sp Scale was administered simultaneously to a Visual Analogical Scale-VAS. Three different observational conditions were established: resting condition, during presumably pleasant activity and during presumable painful activity.

Results

Cronbach's alpha ranged between 0.467 and 0.827 (average 0.692), and rose if Breathing item was deleted. Inter-rater reliability ranged between 0.587 and 0.956. Correlation between PAINAD-Sp Scale total measures and VAS was statistically significant (P<.05) in all measures and ranged from 0.517 to 0.868.

Conclusions

Findings in the study showed that the scale is useful to measure pain in non communicative patients suffering from dementia. The scale maintains good levels of reliability for different healthcare professionals even when they have little training.  相似文献   
929.
Although the interaction between the growing spinal cord and the vertebrae has been widely demonstrated for mammal’s prenatal and early postnatal life, there is no extensive knowledge about this interaction during late postnatal stages. It has been shown that spinal cord injuries are causally related to significant degenerative changes in bone properties. Nevertheless, information about a possible influence of the spinal cord on bone remodelling in adult healthy animals is missing. The aim of this research work was to assess possible morphological changes of the cervical vertebral canal of juvenile and aged rats during the ontogenetic period of adulthood that would justify the suggested influence. Since the spinal cord of rats increases its size with ageing, we analysed whether morphometric changes are occurring in the vertebral canal that would indicate bone remodelling in response to said growth. To this end, we used three complementary morphometric methods to describe the canal of the cervical and the first thoracic vertebrae. Geometric morphometric analyses evidence scarce variation in size and shape between juvenile and aged rats suggesting that, in general terms, the canal morphology of cervical vertebrae is already prepared in early adulthood to host the growing spinal cord. C3 was the only vertebra that showed consistent variation for the variables of canal thickness, perimeter, height and area. This regional variation may be linked to the patterns described for the changing spinal cord.  相似文献   
930.
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