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A piece of lignitized wood from the Miocene of Senftenberg, Germany, was identified as a type of compression wood, and was studied anatomically, as groundwork, in an investigation on cell wall cellulose and lignin. The wood showed affinity to modern Cryptomeria and Taxodium. In each growth ring the early wood was compacted. By contrast, cellular structure in the late wood had been retained to a high degree. Massive compaction of the early wood most likely occurred during the initial stages of sedimentation prior to mineralization. Numerous cell wall deformations in late wood tracheids apparently originated from compressive forces applied to the wood during sedimentation. 相似文献
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Elsie Collyer 《New Zealand journal of zoology.》2013,40(2):271-279
Abstract Studies were made in an orchard near Nelson from 1974 to 1978 on integrated control of Panonychus ulmi (Koch) using the organophosphate-resistant predator Typhlodromus pyri Scheuten. Correct timing of selective acaricides during the October-January period is essential, and can be achieved by close observation of P. ulmi development. When the majority of winter eggs have hatched (late October to early November), or the majority of the summer eggs laid by the first generation (very late November to early or mid December), there is a short period when a maximum of immature mites occurs. This is before many adult females have matured, and is the most effective time for application of an acaricide such as cyhexatin. The development of P. ulmi, in particular the incubation period of the summer eggs, is controlled by temperature, and in seasons when mean temperatures are well below average in November and December the delayed mite development makes accurate timing of the December spray more difficult. Other factors which also affect mite development are the use of dormant oil, cultivar, and orchard aspect and shelter. On the block of trees where no acaricides were used since 1968, although regular applications of azinphos-methyl were made, T. pyri maintained P. ulmi at acceptable levels over the 5 years 1973-78, a maximum of P. ulmi occurring each season in January with the third generation. In three seasons the peak was well below the threshold for commercial spraying; in two seasons this threshold was exceeded, but despite the absence of acaricides P. ulmi numbers soon fell. A further experiment demonstrated the utility of mineral oil and cyhexatin as selective acaricides in integrated programmes. Cycloprate, tricyclotin, and fenbutatin oxide were shown to be as effective and selective as cyhexatin, a single application in early December giving good survival of T. pyri and season-long control of P. ulmi. In another experiment propargite was as effective and selective as cyhexatin; amitraz was more toxic to T. pyri and less persistent against P. ulmi, and resulted in a poor P. ulmi : T. pyri ratio; and chlorpyrifos, though not more toxic than cyhexatin to T. pyri, was less effective against P. ulmi. Mancozeb, and dinocap + mancozeb, used in a summer-long programme of 12 treatments, were more toxic to T. pyri than were binapacryl or dinocap alone. 相似文献
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Elsie M. B. Sorensen Daniel Acosta 《In vitro cellular & developmental biology. Plant》1984,20(10):763-770
Summary Freshly isolated hepatocytes from neonatal rats were cultured for approximately 24 h; incubated for 5, 30, or 60 min in solutions
containing 0, 50, 100, or 200 μM cadmium; embedded in plastic; and sectioned for optical microscopy. The exeent of cadmium-induced hepatotoxicity was evaluated
by double-blind morphometric analysis (a geometricostatistical processing of two-dimensional data for the collection of threedimensional
information) whereby hepatocytes were classified on the basis of the severity of morphologic damage at the optical level.
Both time and concentration effects were studied. Cultures exposed to 200 μM cadmium, for various intervals of time from 5 to 60 min, showed statistically significant reductions in the relative volume
percent of normal hepatocytes, elevations (then reductions) in the relative volume percent of slightly damaged hepatocytes,
increases in the relative volume percent of moderately damaged cells, and increases in the relative volume percent of severely
damaged liver cells. As the concentration of cadmium was increased from 50 to 200 μM cadmium (during both 30 and 60-min exposures), significant trends were observed in cellular distribution patterns based on
relative volume percent. Morphologically normal cells decreased, both slightly damaged and moderately damaged cells increased,
and severely damaged cells remained unchanged. These results indicated that morphometric analysis at the optical level provided
quantitative estimates for the evaluation of time- and concentration-effects of cadmium on cultured hepatocytes.
This work was supported by a grant from the Johns Hopkins University Center for Alternatives to Animal Testing. 相似文献
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Naveen Poonai Kriti Kumar Kamary Coriolano Graham Thompson Shaily Brahmbhatt Emily Dzongowski Holly Stevens Priti Gupta Michael Miller Sharlene Elsie Dhandapani Ashok Gary Joubert Rod Lim Andreana Bütter Samina Ali 《CMAJ》2020,192(48):E1612
BACKGROUND:Less than two-thirds of children with abdominal pain in the emergency department receive analgesia. We sought to determine whether hyoscine butylbromide was superior to acetaminophen for children with nonspecific colicky abdominal pain.METHODS:We randomly allocated children aged 8–17 years with nonspecific colicky abdominal pain who presented to the pediatric emergency department of London Health Sciences Centre, London, Ontario to receive hyoscine butylbromide, 10 mg given orally, or acetaminophen, 15 mg/kg given orally (maximum 975 mg). We considered the minimal clinically important difference for the primary outcome (self-reported pain at 80 min) to be 13 mm on a 100 mm visual analogue scale. Secondary outcomes included administration of rescue analgesia, adverse effects and pain score less than 30 mm at 80 minutes.RESULTS:A total of 236 participants (120 in the hyoscine butylbromide group and 116 in the acetaminophen group) were included in the trial. The mean visual analogue scale scores at 80 minutes were 29 mm (standard deviation [SD] 26 mm) and 30 mm (SD 29 mm) with hyoscine butylbromide and acetaminophen, respectively (adjusted difference 1, 95% confidence interval −7 to 7). Rescue analgesia was administered to 4 participants (3.3%) in the hyoscine butylbromide group and 1 participant (0.9%) in the acetaminophen groups (p = 0.2). We found no significant differences in rates of adverse effects between hyoscine butylbromide (32/116 [27.6%]) and acetaminophen (28/115 [24.3]) (p = 0.5); no serious adverse effects were observed. The proportion with a pain score less than 30 mm at 80 minutes was 66 (55.0%) with hyoscine butylbromide and 63 (54.3%) with acetaminophen (p = 0.9).INTERPRETATION:Hyoscine butylbromide was not superior to acetaminophen in this setting. Both agents were associated with clinically important pain reduction, and either can be considered for children presenting to the emergency department with nonspecific colicky abdominal pain. Trial registration: Clinicaltrials.gov, no. Abdominal pain is reported by a third of school-aged children NCT025823071 and accounts for several visits daily in most emergency departments.2–5 Although the use of analgesia to treat acute abdominal pain is well-supported,6,7 there is little evidence to guide the management of nonspecific abdominal pain in the emergency department,8 which accounts for two-thirds of cases of abdominal pain presenting to the emergency department.8,9 Acetaminophen is the most commonly used World Health Organization Step 1 analgesic.10 In children, it is effective for many painful conditions,11,12 but data supporting its use for abdominal pain are lacking.13,14 Despite strong advocacy by the American Academy of Pediatrics15 for adequate pain management, less than two-thirds of children with abdominal pain in the emergency department receive analgesia,16,17 and roughly half experience ongoing pain after discharge. 18 Children with nonspecific abdominal pain are less likely than those with a specific cause to receive analgesia.5 Available analgesic options for children with nonspecific abdominal pain in the emergency department may result in greater adherence to the American Academy of Pediatrics recommendations.Hyoscine butylbromide is orally administered and available in most Canadian emergency departments. We surmised that it may be effective for colicky abdominal pain owing to its antispasmodic properties.19 Ten placebo-controlled studies involving 3699 adults with functional abdominal pain showed hyoscine butylbromide to be beneficial, without serious adverse effects.20–29 In the only pediatric study, hyoscine butylbromide, 10 mg given orally, was found to be beneficial compared to a homeopathic preparation in 204 children, with no serious adverse effects.30 We sought to determine whether hyoscine butylbromide was superior to acetaminophen in relieving pain among children presenting to the emergency department with nonspecific colicky abdominal pain. 相似文献
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