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991.
Rebecca Robinson Yu‐Mei Chang Christopher J Seymour Ludovic Pelligand 《Veterinary anaesthesia and analgesia》2014,41(3):259-268
ObjectiveTo evaluate mortality in a canine population undergoing thoracic surgery and identify factors which may be associated with outcome.Study designRetrospective cohort study.Animals286 dogs anaesthetized for thoracic surgery at the Royal Veterinary College between June 2002 – June 2011.MethodsVariables examined included: signalment; ASA status; nature of disease; presence of co-morbidities; pre-anaesthetic oxygen requirement; surgical approach; anaesthesia management [anaesthetic agents; requirement for thoracocentesis; central venous pressure measurement; duration of surgery and anaesthesia; use of colloids, blood products, inotropes or neuromuscular blocking agents (NMBA)]. Outcome was defined as either non-survival to 24 hours after surgery or (having survived to 24 hours) to discharge. Univariate and multivariable logistic regressions were performed to identify risk factors associated with non-survival.ResultsOverall non-survival (excluding those euthanased) to discharge was 5.9%. Non-survival was 2.2% at 24 hours and 3.6% at time of discharge. Non-survival to 24 hours was associated with pre-anaesthetic oxygen requirement (odds ratio (OR) 12.2 [95% CI 1.8–84.5]) and NMBA use (OR 9.6 [95% CI 1.6–57.9]). Non-survival to discharge was associated with surgical duration, with surgeries >180 minutes having OR 16.9 [95% CI 2.0–144.0] compared to surgeries ≤90 minutes and blood product use (OR 4.6 [95% CI 1.3–14.6]). No association was found between ASA category and non-survival at 24 hours (OR 1.4 [95% CI 0.2–11.7]) or discharge (OR 4.4 [95% CI 0.6–34.3]). Significant associations were found between NMBA use and ASA category (p = 0.046), surgical duration (p = 0.002), use of colloids (p = 0.011), blood products (p = 0.001) and inotropes and/or vasopressors (p < 0.001).Conclusions and clinical relevanceVariables significantly associated with non-survival from canine thoracic surgery at 24 hours include NMBA use and pre-anaesthetic oxygen requirement. Blood product use and increasing surgical duration were associated with non-survival to hospital discharge. The associations may relate to the need for such products in the most complicated cases. 相似文献
992.
993.
Riggs Rebecca Anne Achdiawan Ramadhani Adiwinata Ani Boedhihartono Agni Klintuni Kastanya Agustinus Langston James Douglas Priyadi Hari Ruiz-Pérez Manuel Sayer Jeffrey Tjiu Albertus 《Landscape Ecology》2021,36(8):2409-2426
Landscape Ecology - In recent years, landscape sustainability, the maintenance and improvement of biodiversity, ecosystem services, and human well-being in landscapes, has become a core objective... 相似文献
994.
Despite the commercial approval of twenty-five transgenic crops in the U.S. as of mid-1996, concern is still being expressed
regarding the potential risks associated with genetically engineered crops. One recurring issue is the possibility of pollen-mediated
escape of engineered genes into populations of crop wild relatives. To address this concern, the scientific community has
depended on literature on pollen dispersal generated from non-transgenic organisms. Utilization of this information requires
the assumption that the pollen mediated movement of native and transgenes is the same. To test the validity of this assumption,
we directly compared the pollen-mediated gene movement of native and engineered marker genes using melon plants (Cucumis melo
L.) expressing dominant morphological and transgenic traits. Movement into both contiguous border plots and non-contiguous
satellite plots were monitored. Dispersal of the native gene and transgene into the satellite plots was identical. Dispersal
of the two traits into the plot borders was nearly identical. Of the nearly 4600 seedlings screened for both morphological
(presence of green vs. virescent cotyledons) and transgene movement (presence of NPT II protein by ELISA), in no case was
the NPT II gene observed in the absence of green cotyledons. However, 39 seedlings were green but did not express NPT II as
measured by ELISA. PCR analysis revealed transgene inactivation as a cause of the NPT II ELISA-seedlings.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
995.
Rebecca N. Brown Alfredo Bolanos-Herrera James R. Myers Molly Miller Jahn 《Euphytica》2003,129(3):253-258
Cucurbita moschata cv. Nigerian Local has been used as a source of resistance to Zucchini yellow mosaic virus (ZYMV), Watermelon mosaic virus (WMV), Papaya ringspot virus W (PRSV-W) and Cucumber mosaic virus (CMV) in breeding both Cucurbita moschata and Cucurbita pepo. We used the F1, F2 and BC1 generations derived from the cross C.-moschata cv. Waltham Butternut × Nigerian Local to study the inheritance of resistance to each of the viruses. We confirmed monogenic
dominant resistance to ZYMV previously attributed to Zym, and we report monogenic dominant resistance to WMV and CMV which we propose to designate
Wmv and Cmv, respectively. A single recessive gene, which we propose to designate prv, controls resistance to PRSV. DNA samples were extracted from a Waltham Butternut BC1 F1 population screened with ZYMV and analyzed using randomly amplified polymorphic DNA markers. No RAPD markers linked to ZYMV
resistance were found.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
996.
Downy mildew on lettuce is currently controlled using host resistance genes (Dm genes) that confer race-specific resistance in seedlings. Field resistance (FR) that is active in adult plants but not seedlings was identified in the cvs. Grand Rapids and Iceberg. The goal of our study was to evaluate the utility of Grand Rapids as a source of novel Bremia resistance alleles, particularly in comparison with Iceberg. To measure FR, downy mildew symptoms were evaluated following natural infection in field experiments. The responses of Grand Rapids and Iceberg were similar in many respects. Although both cultivars had a small percentage of plants exhibiting disease symptoms, the average disease ratings were as low as for cultivars with effective Dm genes. We observed no evidence for race specificity. FR was effective over 3 years of our study, despite documented variation within pathogen populations. Both cultivars lacked all known seedling resistance genes except Dm13, which was not responsible for the resistance observed in field experiments. Similar segregation of FR was observed in F2 populations for both Grand Rapids and Iceberg. The presence of highly susceptible families within Grand Rapids × Iceberg populations suggested the presence of at least one unique resistance allele in each cultivar. Preliminary genetic analysis of FR from Grand Rapids revealed a high estimate of narrow-sense heritability that suggested simple inheritance, but single gene models did not fit the observed data. Our results suggest that Grand Rapids may represent an underutilized resource for controlling downy mildew in lettuce. 相似文献
997.
Joseph C. Fetter Rebecca N. Brown Josef H. Görres Chong Lee José A. Amador 《Water, air, and soil pollution》2012,223(4):1531-1541
Consumer demand for cleaned squid generates a substantial amount of waste that must be properly disposed of, creating an economic
burden on processors. A potential solution to this problem involves converting squid by-products into an organic fertilizer,
for which there is growing demand. Because fertilizer application to lawns can increase the risk of nutrient contamination
of groundwater, we quantified leaching of NO3–N and PO4–P from perennial ryegrass turf (Lolium perenne L.) amended with two types of fertilizer: squid-based (SQ) and synthetic (SY). Field plots were established on an Enfield
silt loam, and liquid (L) and granular (G) fertilizer formulations of squid and synthetic fertilizers were applied at 0, 48,
146, and 292 kg N ha−1 year−1. Levels of NO3–N and PO4–P in soil pore water from a depth of 60 cm were determined periodically during the growing season in 2008 and 2009. Pore
water NO3–N levels were not significantly different among fertilizer type or formulation within an application rate throughout the
course of the study. The concentration of NO3–N remained below the maximum contaminant level (MCL) of 10 mg L−1 until midSeptember 2009, when values above the MCL were observed for SQG at all application rates, and for SYL at the high
application rate. Annual mass losses of NO3–N were below the estimated inputs (10 kg N ha−1 year−1) from atmospheric deposition except for the SQG and SYL treatments applied at 292 kg N ha−1 year−1, which had losses of 13.2 and 14.9 kg N ha−1 year−1, respectively. Pore water PO4–P levels ranged from 0 to 1.5 mg P L−1 and were not significantly different among fertilizer type or formulation within an application rate. Our results indicate
that N and P losses from turf amended with squid-based fertilizer do not differ from those amended with synthetic fertilizers
or unfertilized turf. Although organic in nature, squid-based fertilizer does not appear to be more—or less—environmentally
benign than synthetic fertilizers. 相似文献
998.
Rebecca M. Page Stefan Scheidler Elif Polat Paul Svoboda Peter Huggenberger 《Water, air, and soil pollution》2012,223(5):2771-2782
Faecal contamination of drinking water extracted from alluvial aquifers can lead to severe problems. River water infiltration can be a hazard for extraction wells located nearby, especially during high discharge events. The high dimensionality of river?Cgroundwater interaction and the many factors affecting bacterial survival and transport in groundwater make a simple assessment of actual water quality difficult. The identification of proxy indicators for river water infiltration and bacterial contamination is an important step in managing groundwater resources and hazard assessment. The time resolution of microbial monitoring studies is often too low to establish this relationship. A proxy-based approach in such highly dynamic systems requires in-depth knowledge of the relationship between the variable of interest, e.g. river water infiltration, and its proxy indicator. In this study, continuously recorded physico-chemical parameters (temperature, electrical conductivity, turbidity, spectral absorption coefficient, particle density) were compared to the counts for faecal indicator bacteria, Escherichia coli and Enterococcus sp. obtained from intermittent sampling. Sampling for faecal indicator bacteria was conducted on two temporal scales: (a) routine bi-weekly monitoring over a month and (b) intense (bi-hourly) event-based sampling over 3 days triggered by a high discharge event. Both sampling set-ups showed that the highest bacterial concentrations occurred in the river. E. coli and Enterococcus sp. concentrations decreased with time and length of flow path in the aquifer. The event-based sampling was able to demonstrate differences in bacterial removal between clusters of observation wells linked to aquifer composition. Although no individual proxy indicator for bacterial contamination could be established, it was shown that a combined approach based on time-series of physico-chemical parameters could be used to assess river water infiltration as a hazard for drinking water quality management. 相似文献
999.
Landscape Ecology - In many regions of the world, Indigenous people continue to shape landscape patterns using fire. Some studies show that Indigenous fire regimes create a diverse “visible... 相似文献
1000.
Contribution of human alpha-defensin 1, 2, and 3 to the anti-HIV-1 activity of CD8 antiviral factor 总被引:1,自引:0,他引:1
Zhang L Yu W He T Yu J Caffrey RE Dalmasso EA Fu S Pham T Mei J Ho JJ Zhang W Lopez P Ho DD 《Science (New York, N.Y.)》2002,298(5595):995-1000
It has been known since 1986 that CD8 T lymphocytes from certain HIV-1-infected individuals who are immunologically stable secrete a soluble factor, termed CAF, that suppresses HIV-1 replication. However, the identity of CAF remained elusive despite an extensive search. By means of a protein-chip technology, we identified a cluster of proteins that were secreted when CD8 T cells from long-term nonprogressors with HIV-1 infection were stimulated. These proteins were identified as alpha-defensin 1, 2, and 3 on the basis of specific antibody recognition and amino acid sequencing. CAF activity was eliminated or neutralized by an antibody specific for human alpha-defensins. Synthetic and purified preparations of alpha-defensins also inhibited the replication of HIV-1 isolates in vitro. Taken together, our results indicate that alpha-defensin 1, 2, and 3 collectively account for much of the anti-HIV-1 activity of CAF that is not attributable to beta-chemokines. 相似文献