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241.
M Bush R J Montali D G Kleiman J Randolph M D Abramowitz R F Evans 《Journal of the American Veterinary Medical Association》1980,177(9):858-862
Diaphragmatic defects were identified in 11 of 130 golden lion tamarins. Seven of the cases were found at necropsy (52 tamarins) and 4 were diagnosed by radiography (78 tamarins). When screening radiography revealed a thoracic mass, a barium series was indicated and either demonstrated loops of bowel within the thorax or suggested liver displacement by the cranial location of the intestine. In 1 case, pneumoperitoneum aided in the diagnosis, by showing liver displacement cranially in an eventration of the diaphragm. The 4 defects diagnosed clinically were successfully corrected surgically. The defects mainly involved the ventromedial to lateral aspect of the costal and sternal muscular portions of the diaphragms. Either a thin pleuroperitoneal sac remained or wide gaps were associated with herniation of abdominal contents into the thorax. Of the 11 affected tamarins, 10 were closely related and the other had no direct consanguinity. An autosomal recessive mode of inheritance was suggested, but other genetic factors may have been involved. 相似文献
242.
Shih C Museth AK Abrahamsson M Blanco-Rodriguez AM Di Bilio AJ Sudhamsu J Crane BR Ronayne KL Towrie M Vlcek A Richards JH Winkler JR Gray HB 《Science (New York, N.Y.)》2008,320(5884):1760-1762
Energy flow in biological structures often requires submillisecond charge transport over long molecular distances. Kinetics modeling suggests that charge-transfer rates can be greatly enhanced by multistep electron tunneling in which redox-active amino acid side chains act as intermediate donors or acceptors. We report transient optical and infrared spectroscopic experiments that quantify the extent to which an intervening tryptophan residue can facilitate electron transfer between distant metal redox centers in a mutant Pseudomonas aeruginosa azurin. Cu(I) oxidation by a photoexcited Re(I)-diimine at position 124 on a histidine(124)-glycine(123)-tryptophan(122)-methionine(121) beta strand occurs in a few nanoseconds, fully two orders of magnitude faster than documented for single-step electron tunneling at a 19 angstrom donor-acceptor distance. 相似文献
243.
PWM Kronen DVM PF Moon-Massat DVM DipACVA JW Ludders DVM DipACVA RD Gleed BVSc MRCVS DVA DipACVA DipECVA TJ Kern DVM DipACVO J Randolph DVM DipACVIM H N Erb DVM MS PhD 《Veterinary anaesthesia and analgesia》2001,28(3):146-155
Objective To evaluate the effectiveness of two insulin doses to maintain an acceptable range of blood glucose concentrations (70–200 mg dL?1) in the peri‐operative period in diabetic dogs. Animals Twenty‐four diabetic dogs with a median weight of 20.6 kg and a median age of 8 years old. Methods The dogs were randomly assigned to receive either 25 or 100% of their normal insulin dose subcutaneously on the morning of surgery. The anesthetic and feeding protocols were standardized. On the day before surgery, venous blood was collected for measurement of β‐hydroxybutyrate, cholesterol, glucose, glycosylated hemoglobin, hematocrit, total plasma protein and urea nitrogen. On the day of surgery, blood glucose concentrations were measured prior to anesthesia, prior to the start of surgery, 1 and 2 hours after beginning of surgery, 1 hour after extubation, at 16 : 00 hours and at 20 : 00 hours. β‐hydroxybutyrate concentrations were measured at 20 : 00 hours that day. At 08 : 00 hours the following day, β‐hydroxybutyrate and glucose concentrations were measured. The significance of differences between groups was tested with Wilcoxon's two‐tailed rank‐sum test, Chi‐square test and Fisher's exact test. Results There were no differences in insulin treatments, clinical signs, concurrent diseases and most clinicopathological parameters between the two groups of dogs at entry to the study. The 25% dose group had blood glucose values of 296 (102–601) mg dL?1 at 16 : 00 hours and 429 (97–595) mg dL?1 at 20 : 00 hours on the day of surgery. The 100% insulin dose group had lower corresponding values of 130 (55–375) mg dL?1 (p = 0.04) and 185 (51–440) mg dL?1 (p = 0.004). No other differences (p < 0.05) were detected between the two groups. Conclusions The administration of a full dose of insulin is only marginally advantageous for reducing glucose to normal (70–120 mg dL?1) after anesthesia but neither dose consistently induced glycemic values in an acceptable range (70–200 mg dL?1) or normoketonemia. Clinical relevance Blood glucose should be measured immediately before anesthesia and periodically throughout the peri‐operative period in all diabetic dogs because presurgical subcutaneous administration of 25 or 100% of the normal insulin dose resulted in unpredictable blood glucose concentrations. 相似文献
244.
David J. Luckett Raymond B. Cowley Mark F. Richards David M. Roberts 《European journal of plant pathology / European Foundation for Plant Pathology》2009,125(1):131-141
Pleiochaeta root rot (PRR) caused by Pleiochaeta setosa is a serious, widespread fungal disease in lupin crops, especially in Lupinus albus (broad-leaf lupin, or white lupin). PRR resistance is common in the gene pool of L. albus with various landraces from the Mediterranean region being the most resistant, and suitable for use in breeding new cultivars.
Heritability of resistance is sufficient to make good gains from selection but only when controlled-environment (CE) screening
is used. Field disease nurseries on loamy soil gave much lower heritability of resistance. Field disease nurseries had spatially
variable spore counts despite continuous lupin cropping, and this was partly responsible (along with climatic conditions)
for their reduced precision compared to tests conducted in a CE. Giving infected L. albus roots a single, most-severe-lesion score on a 0–9 scale was adequate for CE screening but not as precise or discriminating
as the more time-consuming method of six scores per root. Replication in CE experiments was reduced to two pots of 16 seedlings
each without sacrificing genotype discrimination. 相似文献
245.
The average mortality for end of lay hens dead on arrival (DOA) was 0.27 per cent (median 0.15 per cent) in a survey of 13.3 million hens transported during 2009. A statistical model of the data indicated main risk factors for DOA to be slaughter plant, distance travelled and external air temperature, with longer journeys and low external air temperatures increasing the risk. Other highly significant risk factors (P<0.001) related to the condition of the birds on farm, where an increased risk of DOA was positively associated with poor feather cover, lower body weight, cumulative mortality of the flock and poor health (indicated by a high proportion of the load rejected at the plant for traumatic injury and disease state). However, the data indicate that by taking risk factors into consideration it is possible to transport hens up to 960 km with low losses in temperate conditions. Mean levels of on-farm mortality, during the laying period, for a total of 1486 flocks were significantly lower in cages (5.39 per cent) than in barn (8.55 per cent), free-range (9.52 per cent) or organic flocks (8.68 per cent) according to producer records a median of seven days before depopulation, with considerable variation between flocks in all systems. 相似文献
246.
Qualitative and quantitative methods were used to investigate how shopping behaviors and environment influence dietary intake
and weight status among homeless Minnesotans living in food deserts. Seven focus groups (n = 53) and a quantitative survey (n = 255), using the social cognitive theory as the theoretical framework, were conducted at two homeless shelters (S1 and S2)
in the Twin Cities area. Heights, weights, and 24-h dietary recalls were also collected. Food stores within a five-block radius
of the shelters were evaluated for the price and availability of foods and compared to the Thrifty Food Plan’s market basket
prices (MBP). Results showed that almost 80% of the sample was overweight or obese, with women consuming less than the recommended
level for the fruits, vegetables, and milk food groups and excess for the fats/oils/sweets food group. Focus groups and participant
surveys indicated that the shelter infrastructure and surrounding community influenced the types of foods available, food
store access, and the foods purchased and consumed. Participants relied on food assistance programs, including food stamps,
to supplement their food supply; however, some felt the high food prices at neighboring stores limited food choice and that
food stamps did not adequately cover food costs. Results from the food store survey found the majority of food prices exceeded
Midwest or national MBP. To promote healthier dietary intake and weight status, community-based interventions and city planners
should aim to increase access to food through improved food availability and food access within the shelter environment and
surrounding community. 相似文献
247.
248.
Puffy skin disease (PSD) in rainbow trout,Oncorhynchus mykiss (Walbaum): a case definition 下载免费PDF全文
C E Maddocks E T Nolan S W Feist M Crumlish R H Richards C F Williams 《Journal of fish diseases》2015,38(7):653-664
Puffy skin disease (PSD) is a disease that causes skin pathology in rainbow trout, Oncorhynchus mykiss (Walbaum). Incidence of PSD in UK fish farms and fisheries has increased sharply in the last decade, with growing concern from both industry sectors. This paper provides the first comprehensive case definition of PSD, combining clinical and pathological observations of diseased rainbow trout from both fish farms and fisheries. The defining features of PSD, as summarized in the case definition, were focal lateral flank skin lesions that appeared as cutaneous swelling with pigment loss and petechiae. These were associated with lethargy, poor body condition, inappetance and low level mortality. Epidermal hyperplasia and spongiosis, oedema of the dermis stratum spongiosum and a mild diffuse inflammatory cellularity were typical in histopathology of skin. A specific pathogen or aetiology was not identified. Prevalence and severity of skin lesions was greatest during late summer and autumn, with the highest prevalence being 95%. Atypical lesions seen in winter and spring were suggestive of clinical resolution. PSD holds important implications for both trout aquaculture and still water trout fisheries. This case definition will aid future diagnosis, help avoid confusion with other skin conditions and promote prompt and consistent reporting. 相似文献
249.
Michelle D. Staudinger Katherine E. Mills Karen Stamieszkin Nicholas R. Record Christine A. Hudak Andrew Allyn Antony Diamond Kevin D. Friedland Walt Golet Meghan Elisabeth Henderson Christina M. Hernandez Thomas G. Huntington Rubao Ji Catherine L. Johnson David Samuel Johnson Adrian Jordaan John Kocik Yun Li Matthew Liebman Owen C. Nichols Daniel Pendleton R. Anne Richards Thomas Robben Andrew C. Thomas Harvey J. Walsh Keenan Yakola 《Fisheries Oceanography》2019,28(5):532-566
The timing of recurring biological and seasonal environmental events is changing on a global scale relative to temperature and other climate drivers. This study considers the Gulf of Maine ecosystem, a region of high social and ecological importance in the Northwest Atlantic Ocean and synthesizes current knowledge of (a) key seasonal processes, patterns, and events; (b) direct evidence for shifts in timing; (c) implications of phenological responses for linked ecological‐human systems; and (d) potential phenology‐focused adaptation strategies and actions. Twenty studies demonstrated shifts in timing of regional marine organisms and seasonal environmental events. The most common response was earlier timing, observed in spring onset, spring and winter hydrology, zooplankton abundance, occurrence of several larval fishes, and diadromous fish migrations. Later timing was documented for fall onset, reproduction and fledging in Atlantic puffins, spring and fall phytoplankton blooms, and occurrence of additional larval fishes. Changes in event duration generally increased and were detected in zooplankton peak abundance, early life history periods of macro‐invertebrates, and lobster fishery landings. Reduced duration was observed in winter–spring ice‐affected stream flows. Two studies projected phenological changes, both finding diapause duration would decrease in zooplankton under future climate scenarios. Phenological responses were species‐specific and varied depending on the environmental driver, spatial, and temporal scales evaluated. Overall, a wide range of baseline phenology and relevant modeling studies exist, yet surprisingly few document long‐term shifts. Results reveal a need for increased emphasis on phenological shifts in the Gulf of Maine and identify opportunities for future research and consideration of phenological changes in adaptation efforts. 相似文献
250.
Eben N. Broadbent Angélica M. Almeyda Zambrano Rodolfo Dirzo William H. Durham Laura Driscoll Patrick Gallagher Rosalyn Salters Jared Schultz Angélica Colmenares Shannon G. Randolph 《Landscape Ecology》2012,27(5):731-744
Development in biodiversity rich areas is of global concern. While development may lead to socioeconomic benefits, this often
comes concomitant with biodiversity loss and deforestation. Biodiversity rich areas present the opportunity for both improvements
in socioeconomic conditions and conservation; however numerous challenges exist. Costa Rica’s Manuel Antonio National Park
presents an ideal case study to investigate the balance between alternative forms of development which have contrasting environmental
impacts. The Manuel Antonio region is a highly dynamic landscape experiencing deforestation, from agriculture, cattle ranching
and oil palm plantations; and also reforestation from abandonment of land holdings and nature oriented tourism. Landscape
dynamics are closely intertwined with the livelihoods and perspectives on biodiversity conservation of local communities,
determining ecological sustainability. We use an analysis combining multi-temporal remote sensing of land cover dynamics from
1985 to 2008 with questionnaire data from local families on their socioeconomic status, perspectives on conservation, and
perceived changes in local wildlife populations. Our results show that, while regeneration occurred and forest fragmentation
in the area decreased from 1985 to 2008, Manuel Antonio National Park is rapidly becoming isolated. Decreasing ecological
connectivity is related to the rapid expansion of oil palm plantations adjacent to the park and throughout the lowland areas.
Perceived decreases in wildlife abundance and compositional change are evident throughout the area, with local communities
attributing this primarily to illegal hunting activities. Nature based tourism in the area presents an effective strategy
for conservation, including reductions in hunting, through increased valuation of biodiversity and protected areas, and socioeconomic
advantages. However, without urgent efforts to limit deforestation and preserve the remaining forested corridor connecting
the park to core primary forest, the ability to maintain biodiversity in the park will be reduced. 相似文献