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61.
Summary Transmission electron microscopy observations of hemlock sawdust that had been incubated with concentrated filtrate from Postia placenta showed that wood was degraded despite the absence of weight loss and release of reducing groups. These results are contrary to the prevailing views that enzyme preparation from brown-rot fungi are unable to degrade wood.Maintained at Madison, WI, in cooperation with the University of Wisconsin 相似文献
62.
Summary Hemlock sawdust samples degraded by Ganoderma applanatum showed no electron-dense particles either in hyphae or in wood cell walls after aldehyde/OsO4 fixation. After KMnO4 fixation at early stage of attack, particles were in hyphae, hyphal sheath and wood cell walls. In samples prepared by a cytochemical technique which localizes cellulase activity at the ultrastructural level, particles were in hyphae, hyphal sheath and wood cell walls. The smallest diameter range of the particles lay between 3 and 7 nm which corresponds to the size of cellulases. Larger diameter particles were peresent which are probably aggregates of the smaller units. We believe that particles present in hyphal cytoplasm and hyphal sheath are cellulolytic enzymes. Whether particles present in attacked wood cell walls are enzymes or degradation products cannot be determined by this study. Nevertheles, the particles reveal the decay pattern in wood by the white-rot fungus G. applanatum. 相似文献
63.
ASSESSMENT OF RESPIRATION‐INDUCED DISPLACEMENT OF CANINE ABDOMINAL ORGANS IN DORSAL AND VENTRAL RECUMBENCY USING MULTISLICE COMPUTED TOMOGRAPHY 下载免费PDF全文
Cintia R. Oliveira Margaret A. Henzler Rebecca A. Johnson Randi Drees 《Veterinary radiology & ultrasound》2015,56(2):133-143
Respiratory‐induced organ displacement during image acquisition can produce motion artifacts and variation in spatial localization of an organ in diagnostic computed tomography (CT) examinations. The purpose of this prospective study was to quantify respiratory‐induced abdominal organ displacement in dorsal and ventral recumbency using five normal dogs. All dogs underwent CT examinations using 64 multidetector row CT (64‐MDCT). A “3‐dimensional (3D) apneic CT exam” of the abdomen was acquired followed by a “4‐dimensional (4D) ventilated CT exam.” The liver, pancreas, both kidneys, both medial iliac lymph nodes, and urinary bladder were delineated on the 3D‐apneic examination and the organ outlines were compared to the maximum alteration in organ position in the 4D‐ventilated examination. Displacement was measured in dorsal‐to‐ventral (DV), right‐to‐left (RL), and cranial‐to‐caudal (CC) directions. Respiratory‐induced displacement of canine abdominal organs was not predictable and showed large variability in the three directions evaluated. For most canine abdominal organs, dorsal recumbency provided overall the least amount of displacement among all directions evaluated except for liver and urinary bladder. For liver, a large variability was found for all directions and a statistically significant difference was found only in the RL direction with ventral recumbency exhibiting less displacement (P = 0.0099). For the urinary bladder, ventral recumbency also provided less displacement but this was statistically significant only in the RL direction (P < 0.0001). Findings from this study indicated that dorsal recumbency may be preferred for minimizing respiratory motion artifacts in whole abdomen studies, but ventral recumbency may be preferred for liver and urinary bladder studies when respiration cannot be controlled. 相似文献
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65.
Agu RC Brosnan JM Bringhurst TA Palmer GH Jack FR 《Journal of agricultural and food chemistry》2007,55(9):3702-3707
Detailed studies were carried out on the influence of corn size distribution on the values obtained for diastatic power (DP) of commercially malted barley. Malted barley was screened using a screening box, and the DP activities of the different corns retained on the different compartments of the screening box were determined. The malt samples retained on the 2.8 mm screen had the highest DP activity, whereas the small corns (相似文献
66.
Csizmadi I Kahle L Ullman R Dawe U Zimmerman TP Friedenreich CM Bryant H Subar AF 《Public health nutrition》2007,10(1):88-96
BACKGROUND AND OBJECTIVE: Despite assumed similarities in Canadian and US dietary habits, some differences in food availability and nutrient fortification exist. Food-frequency questionnaires designed for the USA may therefore not provide the most accurate estimates of dietary intake in Canadian populations. Hence, we undertook to evaluate and modify the National Cancer Institute's Diet History Questionnaire (DHQ) and nutrient database. METHODS: Of the foods queried on the DHQ, those most likely to differ in nutrient composition were identified. Where possible these foods were matched to comparable foods in the Canadian Nutrient File. Nutrient values were examined and modified to reflect the Canadian content of minerals (calcium, iron, zinc) and vitamins (A, C, D, thiamin, riboflavin, niacin, B6, folate and B12). DHQs completed by 13 181 Alberta Cohort Study participants aged 35-69 years were analysed to estimate nutrient intakes using the original US and modified versions of the DHQ databases. Misclassification of intake for meeting the Dietary Reference Intake (DRI) was determined following analysis with the US nutrient database. RESULTS: Twenty-five per cent of 2411 foods deemed most likely to differ in nutrient profile were subsequently modified for folate, 11% for vitamin D, 10% for calcium and riboflavin, and between 7 and 10% for the remaining nutrients of interest. Misclassification with respect to meeting the DRI varied but was highest for folate (7%) and vitamin A (7%) among men, and for vitamin D (7%) among women over 50 years of age. CONCLUSIOn: Errors in nutrient intake estimates owing to differences in food fortification between the USA and Canada can be reduced in Canadian populations by using nutrient databases that reflect Canadian fortification practices. 相似文献
67.
OBJECTIVE: To evaluate compliance with the World Health Organization's International Code of Marketing of Breast-milk Substitutes in primary care, after the introduction of strict local infant feeding guidelines. DESIGN: An audit form was sent to all community-based health professionals with an infant feeding remit. Walking tours were conducted in a random sample of community care facilities. SETTING: Greater Glasgow Primary Care Division. SUBJECTS: (1) Primary-care staff with an infant feeding remit; (2) community health-care facilities. MAIN OUTCOME MEASURES: Contact with manufacturers of breast-milk substitutes (BMS) and BMS company personnel, free samples or incentives, and advertising of BMS. RESULTS: Contact with company personnel was minimal, usually unsolicited and was mainly to provide product information. Free samples of BMS or feeding equipment were rare but childcare or parenting literature was more prevalent. Staff voiced concerns about the lack of relevant information for bottle-feeding mothers and the need to support the mother's feeding choice. One-third of facilities were still displaying materials non-compliant with the Code, with the most common materials being weight conversion charts and posters. CONCLUSIONS: Contact between personnel from primary care and BMS companies was minimal and generally unsolicited. The presence of materials from BMS companies in health-care premises was more common. Due to the high level of bottle-feeding in Glasgow, primary-care staff stated a need for information about BMS. 相似文献
68.
69.
Lack of Correlation Between Papillomaviral DNA in Surgical Margins and Recurrence of Equine Sarcoids
Sandra D. Taylor Balazs Toth Laura J. Baseler Virginia A. Charney Margaret A. Miller 《Journal of Equine Veterinary Science》2014
Bovine papillomavirus (BPV) types 1 (BPV-1) and 2 (BPV-2) are causally associated with the development of equine sarcoid tumors. Recurrence rates after surgical excision of sarcoids are estimated to be 30%–40%. We hypothesized that the presence of BPV DNA in histologically tumor-free surgical margins of sarcoids is associated with risk of recurrence, and increased quantity of BPV DNA is associated with increased risk of recurrence. Formalin-fixed sarcoids classified as “completely excised” histologically were obtained from two institutions. A total of 25 tumors were included, eight of which recurred within 1 year of excision. Qualitative and quantitative polymerase chain reaction (PCR) tests for detection of BPV-1 and BPV-2 were performed on neoplastic tissue and tumor-free surgical margins in formalin-fixed paraffin-embedded biopsy specimens following DNA extraction. Bovine papillomavirus-1 was found in all tumor samples and in histologically “clean” margins of 21 samples, whereas BPV-2 was found in only two tumor samples. Although quantitative PCR was more sensitive than qualitative PCR in detecting BPV DNA in surgical margins, there was no significant difference in the presence of BPV-1 or BPV-2 DNA in margins of tumors that recurred versus those that did not recur for either test. Although this study is limited by sample size, our results suggest that PCR analysis of surgical margins for BPV DNA is not a reliable method to predict equine sarcoid recurrence after resection. 相似文献
70.
N. B. Martin D. F. Houlihan C. Talbot R. M. Palmer 《Fish physiology and biochemistry》1993,12(2):131-141
Body composition and fractional rates of protein synthesis (percentage of the protein mass synthesized per day) were determined
in female Atlantic salmon returning to the River Tay, Scotland in July and in October after a 95 day period without food,
during which time the animals became sexually mature. During the 95 day period of starvation/sexual maturation the ventricle
and red muscle remained as a constant proportion of fresh weight whereas the liver, gill and ovary increased and the stomach
and white muscle decreased. Fractional rates of protein synthesis increased markedly in the liver, stomach and ovary during
the period of starvation/sexual maturation. In the gill, ventricle and white muscle fractional protein synthesis rates increased
slightly or remained constant. From the estimated rates of protein loss or gain in the various tissues it is concluded that
there is considerable protein turnover and repartitioning of amino acids during the period of starvation and sexual maturation.
The absolute rate of protein synthesis rates in the ovary indicates that this tissue made the largest contribution to the
energy and amino acid demands of the fish, whilst most of the amino acids required for maturation of the ovary were derived
from white muscle, principally as the result of increased muscle protein degradation. 相似文献