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141.
Sommaire Les auteurs donnent un aperçu des essais faits avec six variétés de Cichorium Intybus cultivées et utilisées comme fourrage, comme plante pour pâturages et comme remplaçent le café. L'étude se rapporte aux conditions de la culture et des propriétés agronomiques de la Chicorée, la possibilité de sélection d'une variété spécialement adaptée aux conditions de l'Israel. Biologie, constitution chimique, fûmage etc. fûrent étudiés et les resultats obtenus démontrés sur 15 tableaux.  相似文献   
142.
Signal Transduction in Resistance to Plant Viruses   总被引:7,自引:0,他引:7  
Salicylic acid is part of a signal transduction pathway that induces resistance to viruses, bacteria and fungi. In tobacco and Arabidopsis the defensive signal transduction pathway branches downstream of salicylic acid. One branch induces PR-1 proteins and resistance to bacteria and fungi, while the other triggers induction of resistance to RNA and DNA viruses. This virus-specific branch can be activated using antimycin A and cyanide, or inhibited with salicylhydroxamic acid, suggesting a role for alternative oxidase in resistance to viruses. The virus-specific defensive pathway activates multiple resistance mechanisms. In tobacco, salicylic acid induces resistance to systemic movement of cucumber mosaic virus but has no effect on its replication or cell-to-cell movement. However, in the case of tobacco mosaic virus in tobacco, salicylic acid appears to induce interference with the synthesis of viral RNA.  相似文献   
143.
144.
The objective of this study was to determine healthcare costs attributable to laboratory‐confirmed Lyme disease (LD) from the healthcare payer perspective in Ontario, Canada. A cost‐of‐illness study was conducted for incident LD subjects from 1 January 2006 through 31 December 2013 ascertained from provincial laboratory and reportable disease databases, linked to health administrative data. All LD subjects included were laboratory‐confirmed, according to provincial case definitions. Incident LD subjects were propensity‐score matched to uninfected subjects on age, sex, comorbidities and urban/rural status. We used phase‐of‐care methods to calculate attributable costs for two phases of illness: initial care (≤30 days following “index date”) and continuing care (>30 days after index date to the end of the follow‐up period). A total of 663 incident, confirmed LD subjects were identified from 2006 through 2013. Mean age was 44.2 ± 20.1 years; 339 (51.1%) were female; and 31 (4.7%) were hospitalized ≤30 days after index date. Six hundred fifty‐eight (99.2%) LD subjects were matched to uninfected subjects; mean follow‐up time was 3.3 years. Mean attributable costs per case during the initial care phase and continuing care were $277 (95% CI: $197, $357) and ?$5 (?$27, $17), respectively. Attributable costs per LD subject aged 5–14 years were $440 ($132, $747), greater than the costs observed for other age strata. Expected 1‐year attributable costs were $832, given continuing care costs were negligible. Limitations to our study include estimating costs using a cohort of only laboratory‐confirmed LD cases, introducing selection bias for diagnosed and treated patients who may have a lower risk of developing sequelae. In conclusion, the initial care phase of LD is associated with increased healthcare costs, but without significant costs attributable to LD infection after 30 days. Estimates of costs attributable to LD are important for healthcare resource prioritization and the evaluation of novel interventions.  相似文献   
145.

Objective

Quantify visual acuity of a semi-aquatic turtle species, Terrapene carolina triunguis (three-toed box turtles), utilizing optokinetic response/reflex/nystagmus.

Methods

Ten turtles were placed on a custom platform and an image of white and black gratings of varying sized widths was projected onto a white screen in front of the turtles. Optokinetic response (OKR) was observed through a web camera as well as physically by an observer. The grating sizes were decreased until OKR could not be elicited. The size of grating was recorded and was used to calculate visual acuity.

Results

The average visual acuity was 0.26 cycle per degree (cpd) with the highest recorded value being 0.43 cpd and lowest being 0.15 cpd. Neither sex nor weight were significantly associated with visual acuity (p = .24 and .98, respectively).

Conclusions

Visual acuity of these semi-aquatic turtles was much lower than previously reported visual acuities of aquatic turtles. This could be due to differences in refractive indices between water and air, behavioral adaptations for the different species and/or method of obtaining visual acuity.  相似文献   
146.
This study was conducted to evaluate the total carotene content (TCC) and beta carotene (BC) in the selected underutilized tropical fruits. TCC of underutilized fruits estimated by spectrophotometric method was in the range of 1.4-19.8 mg/100 g edible portion. The TCC of these fruits decreased in the order: Jentik-jentik > Durian Nyekak 2 > Durian Nyekak 1 > Cerapu 2 > Cerapu 1 > Tampoi Kuning > Bacang 1 > Kuini > Jambu Mawar > Bacang 2 > Durian Daun > Bacang 3 > Tampoi Putih > Jambu Susu. BC contents estimated by HPLC method were highest in Jentik-jentik, followed by Cerapu 2, Durian Nyekak 2, Tampoi Kuning, Durian Nyekak 1, and Cerapu 1, which had a range of 68-92% of BC in TCC. These underutilized fruits have an acceptable amount of carotenoids that are potential antioxidant fruits.  相似文献   
147.
Four cases (representing outbreaks in four different ponds on three farms) of branchial mycosis caused by Branchiomyces spp. were identified in channel catfish fry during the summer of 1996. Mortalities ranged from a few hundred to several thousand fish per pond. Significant gross and histopathological findings from these four cases were limited to the gills. All fry examined had fungal mycelia that were mainly but not entirely confined to the base of the primary lamellae and the gill arches. These fungal hyphae were intravascular and occluded vessels in the gill tissues. The present paper describes the fungal characteristics and pathology of branchial mycosis caused by Branchiomyces spp. in channel catfish.  相似文献   
148.
Abstract

Enteric Septicemia of Catfish (ESC) is a ruinous bacterial disease affecting the U.S. catfish industry. Previous attempts to develop ESC vaccines have failed to achieve industry acceptance, largely attributed to difficulties in delivering the vaccine to immunocompetent fish. Recently, a live attenuated ESC vaccine has been developed, coupled with a mechanized platform designed to accurately deliver measured doses of vaccine with feed. This delivery scheme for vaccine-feed admixture has shown tremendous promise under controlled research settings. This study evaluated the economic effects of on-going commercial-vaccination trials on catfish fingerling operations in Mississippi. Commercial-vaccination trials for both channel and hybrid catfish demonstrated significant improvement in survival, growth, feed consumption, feed conversion and gross yield. At a realistic vaccination cost of $750/ha, the net economic benefits to channel and hybrid catfish fingerling-production phases were $3199 and $6145/ha, respectively. Whole-farm models showed additional profit ranging from $71,758 to $133,887/400-ha on farms that integrate fingerling production to their production strategies due to appropriation of more of the otherwise incumbent fingerling production acreage into foodfish production. Commercial adoption of the oral-vaccination platform would greatly enhance profitability while laying the foundation for development and delivery of polyvalent vaccines against other catfish diseases.  相似文献   
149.
Objective: To evaluate the relationship of body weight (BW) and size, dog velocity, and vertical ground reaction forces (GRF) from a large number of dogs of various sizes. Study Design: Clinical research. Animals: Orthopedically healthy dogs (n=129) Methods: BW and dog size, represented as height at the withers (WH), were obtained. Stance times (ST), vertical impulses (VI), and peak vertical forces (PVF) of thoracic and pelvic limbs were measured on a force plate at controlled trotting speed. They were evaluated against BW and WH using linear regression analysis in absolute (nonnormalized) values, and when normalized to BW and/or body size according to the theory of dynamic similarity. Relative velocities were calculated for each dog. Results: Absolute ST, VI, and PVF showed strong positive correlations with BW and/or body size. When GRFs were normalized to BW, correlations with body size were markedly reduced, but remained positive for VI, and turned negative for PVF. Normalizing the time‐dependent variables (ST and VI) also to WH eliminated most size influence. A small dependency of fully normalized GRF on body size remained that was because of differences in relative velocity between dogs of different sizes. Reference values for the fully normalized data are given. Conclusions: The inherent relationship between BW, body size, dog velocity, and vertical GRF was demonstrated. Clinical Relevance: BW, body size, and relative dog velocity must be accounted for when wanting to obtain GRF variables that are comparable between different dogs.  相似文献   
150.
Multiple‐batch production is the most widely practiced method of raising channel catfish. Producers are increasingly adopting intensified production practices in multiple‐batch systems by increasing stocking density and aeration rates as a means to improve cost efficiencies. Proven stocking recommendations are required for the efficient implementation of recent developments in multiple‐batch production. Twelve 0.4‐ha ponds were understocked with 17,484, 20,612, and 26,124 fingerlings/ha (mean weight = 40 g/fish) over equal weights of carryover fish (0.46 kg/fish @ 4,589 kg/ha). Fish were fed once daily to apparent satiation with a 28% protein floating feed and aerated with a single 7.4‐kW electric paddlewheel aerator. Density‐dependent significant differences were absent for gross, net, daily net yields, marketable yields (≥0.54 kg), growth (g/day), and survival. Sub‐marketable yield (<0.54 kg) and feeding rate increased significantly with increased understocking density. Economic analysis revealed increased breakeven prices and diminished net returns with increased stocking density when sub‐marketable fish were not considered as revenue. These differences in production costs and profits among the three treatments became minimal when sub‐marketable fish were included as revenue. All three density treatments attained positive annual net cash flows. This study validates channel catfish understocking densities of 17,000–26,000 fish/ha to improve cost efficiency in intensively aerated, multiple‐batch production systems.  相似文献   
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