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51.
In this work knitted wool fabrics were coated by a Si:Ox:Cy:Hz thin film with the aim to promote pilling resistance. The wool samples were plasma coated in a radio frequency (RF) glow discharge using hexamethyldisiloxane (HMDSO) as the precursor, in mixture with argon and oxygen gases, for different deposition times and reaction pressures, at constant discharge power. Deposited films were characterized by means of Fourier transform infrared (FTIR) spectroscopy and surface morphology by means of scanning electron microscopy; moreover, propensity to pilling of treated samples was investigated, showing that treated fabrics had a better pilling performance respect to untreated ones.  相似文献   
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Drechslera gigantea, a potential mycoherbicide of grass weeds, was isolated in Florida from naturally infected large crabgrass (Digitaria sanguinalis); it produces phytotoxic metabolites in liquid culture. The main metabolite was identified by spectroscopic methods and optical properties as ophiobolin A (1), a well-known phytotoxic sesterterpene produced by several phytopathogenic fungi of important crops and already extensively studied for its interesting biological activities. The other three minor metabolites proved to be related to ophiobolin A and were identified using the same techniques as 6-epi-ophiobolin A and 3-anhydro-6-epi-ophiobolin A (2 and 3) and ophiobolin I (4). Assayed on punctured detached leaves of several grass and dicotyledon weeds, ophiobolin A proved to be on average more phytotoxic as compared to the other related compounds. Some structural features appear to be important for the phytoxicity, such as the hydroxy group at C-3, the stereochemistry at C-6, and the aldehyde group at C-7. Furthermore, grass weeds usually proved to be more sensitive to the phytotoxins than dicotyledons, on which ophiobolin A caused the appearance of large necrosis even at the lowest concentration assayed. This is the first report about the production of ophiobolins from D. gigantea and of the proposed use as potential natural herbicides against grass weeds.  相似文献   
53.
The susceptibility to trypsin of conglutin gamma, a lupin seed glycoprotein affected by this enzyme only when in a non-native conformation, was used to study the effect of Zn(2+) and other metal ions on the structural dynamics of the protein. When acid-treated trypsin-susceptible conglutin gamma was incubated at neutral pH in the presence of Zn(2+), it became resistant to tryptic attack, contrary to the protein treated in the absence of Zn(2+). The time course of this refolding event has been quantitatively evaluated by SDS-PAGE. Amino acid sequencing of the major polypeptide fragments, produced by trypsin before completion of the refolding process, indicated that only a few cleavable bonds were accessible to the enzyme. This suggested that the presence of metal ions affected the pathway of degradation of the protein, by inducing its folding. Among the other metal ions tested, Ni(2+) also promoted the adoption of a trypsin-resistant conformation of conglutin gamma, whereas Mn(2+) and Ca(2+) had only much lower effects. The relevance of these findings for a deeper understanding of the in vivo degradation of plant food proteins and how it is affected by metal ions are discussed.  相似文献   
54.
Non‐tonsillar squamous cell carcinoma (ntSCC) is a common and locally aggressive oral tumour in dogs. The treatments of choice are currently surgery and radiotherapy. Electrochemotherapy (ECT) is a local ablative anti‐tumour technique using electric pulses to enhance the intracellular diffusion of cytotoxic drugs. The aim was to retrospectively evaluate the outcome of patients with oral ntSCC treated with ECT. Twelve dogs with ntSCC were retrospectively enrolled. ECT was combined with IV bleomycin (15 000 UI/m2) alone in 11 cases and post‐surgery in 1. Parameters considered were: tumour site and size, electroporation parameters, response rate (complete remission [CR], partial remission [PR]), median survival time (MST), recurrence rate (RR), median disease‐free interval (DFI) and treatment toxicity (6‐point scale). Median tumour size was 1.65 cm (range 0.3‐8.0 cm) and the response rate was 90.9% (10/11; 8 CR and 2 PR). Two dogs underwent a second ECT. MST for dogs dead with tumour (n = 2) was 110 days and for dogs dead without tumour (n = 3) was 831 days. Among five surviving dogs, one experienced tumour recurrence and four were in CR. Results from two dogs were analysed separately. Overall RR was 27.3%. DFI and MST for dogs with recurrence were 50 and 115 days, respectively. Treatment toxicity was very low. We noticed that all dogs with tumours smaller than 1‐2 cm achieved CR without recurrence suggesting a favourable prognosis when using ECT. ECT for canine ntSCC could be considered a valid treatment option especially for smaller tumours, but a larger caseload would be needed to confirm this statement.  相似文献   
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A strain of Botrytis fabae isolated from faba bean (Vicia faba L.) plants displaying clear chocolate spot disease symptoms produced phytotoxic metabolites in vitro. The phytotoxins isolated from the culture filtrate organic extract were characterized by spectroscopic and optical methods. A new naphthalenone pentaketide, named botrytone, was isolated and characterized as (4R)-3,4-dihydro-4,5,8-trihydroxy-1(2H)-naphthalenone together with other well-known closely related naphthalenones such as regiolone and cis- and trans-3,4-dihydro-2,4,8-trihydroxynaphthalen-1(2H)-ones. When tested on leaves of the host plant, with the cis- and trans-3,4-dihydro-2,4,8-trihydroxynaphthalen-1(2H)-ones assayed in mixture, regiolone demonstrated the highest level of phytotoxicity together with cis- and trans-3,4-dihydro-2,4,8-trihydroxynaphthalen-1(2H)-ones. Botrytone showed moderate phytotoxic activity at 1 mg/mL and was still phytotoxic at 0.5 mg/mL.  相似文献   
58.
ObjectiveTo compare the hemodynamic and respiratory effects of an inspiratory impedance threshold device (ITD) in anesthetized normotensive and hypotensive dogs.Study designProspective randomized study.AnimalsTen adult dogs.MethodsDogs were anesthetized with propofol followed by isoflurane. During spontaneous ventilation, tidal volume ( V˙), systolic (SAP), mean (MAP) and diastolic arterial blood pressure, central venous pressure, gastric PCO2 as an indicator of gastric perfusion, subcutaneous oxygen tension, subcutaneous blood flow, cardiac index (CI), systemic vascular resistance and blood lactate were monitored. To monitor respiratory compliance (RC) and resistance (ResR), animals were briefly placed on mechanical ventilation. Dogs were studied under four different conditions: 1) normotension (MAP > 60 mmHg) with and without the ITD and 2) hypotension (target MAP = 40 mmHg) with and without ITD. These four conditions were performed during one anesthetic period, allowing for stabilization of parameters for each condition. Data were analyzed by anova repeated measure mixed models.ResultsNo cardiovascular changes were detected between no ITD and ITD in the normotensive state. During hypotension, CI was higher with the ITD (5 ± 1.0 L minute?1 m?2) compared with no ITD (4 ± 1.3 L minute?1 m?2). During hypotension, SAP was increased with ITD (80 ± 14 mmHg) versus without ITD (67 ± 13 mmHg). There was an increase in ResR and decreased RC with the ITD in both normotensive and hypotensive state.Conclusion and clinical relevanceImpedance threshold device in dogs during isoflurane-induced hypotension improved CI and SAP but had negative effects on RC and ResR.  相似文献   
59.
The effects of four light intensities (1000 lx, 500 lx, 50 lx, 3 lx) on growth, survival and feeding activity in common sole (Solea solea L.) larvae were studied from 4 to 51 days post hatching (dph). During the pelagic larval stage (4–12 dph), larvae reared at 3 lx showed a lower growth. From 19 onwards, the larvae reared under 3 lx displayed a significant ( 0.05) higher SGR than the other treatments and a higher final weight compared to 1000 lx and 500 lx. Survival rate was higher under intermediate light intensities (500 and 50 lx). Larvae reared at 3 lx displayed a significant delay in the degree of metamorphosis compared to the other treatments, while at 33 dph metamorphosis was completed under all treatments. Histological examination revealed the importance of vision and light in the first feeding of this species, while after metamorphosis, the full development of other sensory organs indicated that feeding activity is also mediated by chemosensory perception. Results indicate that high light intensity seems to be more suitable during the pelagic larvae, while the opposite would ensure better growth from the onset of metamorphosis to the benthic phase.  相似文献   
60.
Eighteen microsatellites were used to investigate the genetic diversity and differentiation of eight Chinese indigenous goat breeds. The results indicated that there is a significant difference of genetic diversity between different loci. Chinese indigenous goat breeds have similar genetic diversity to other Asian goats, but with lower Fst. The clustering of individuals and populations showed that Chinese indigenous goat breeds might have originated from two ancestral populations. The genetic differentiation between populations is consistent with the results of archaeology, mtDNA and RAPD.  相似文献   
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