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41.
Simone Prospero Malve Heinz Eva Augustiny Ying-Yu Chen Juanita Engelbrecht Marina Fonti Aliona Hoste Beat Ruffner Romina Sigrist Noelani van den Berg Patrick Fonti 《Environmental microbiology》2023,25(11):2250-2265
Emerging diseases caused by both native and exotic pathogens represent a main threat to forest ecosystems worldwide. The two invasive soilborne pathogens Phytophthora cinnamomi and Phytophthora × cambivora are the causal agents of ink disease, which has been threatening Castanea sativa in Europe for several centuries and seems to be re-emerging in recent years. Here, we investigated the distribution, causal agents, and infection dynamics of ink disease in southern Switzerland. A total of 25 outbreaks were identified, 19 with only P. cinnamomi, 5 with only P. × cambivora, and 1 with both species. Dendrochronological analyses showed that the disease emerged in the last 20–30 years. Infected trees either died rapidly within 5–15 years post-infection or showed a prolonged state of general decline until death. Based on a generalized linear model, the local risk of occurrence of ink disease was increased by an S-SE aspect of the chestnut stand, the presence of a pure chestnut stand, management activities, the proximity of roads and buildings, and increasing annual mean temperature and precipitation. The genetic structure of the local P. cinnamomi population suggests independent introductions and local spread of the pathogen. 相似文献
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An essential role for an intact vagal nerve has been proven in the development of gastric mucosal cyto- and general protection. On the other hand, chemically-induced (ethanol, HCl, indomethacin) gastric mucosal damage is enhanced after acute surgical vagotomy. The aims of this paper were to study the possible mechanisms of the vagal nerve in the development of gastric mucosal defense. The following questions were addressed: 1) effect of surgical vagotomy on the development of ethanol- (ETOH), HCl-, and indomethacin (IND)-induced gastric mucosal damage; 2) changes in the gastric mucosal defense by scavengers, prostacyclin and other compounds (small doses of atropine and cimetidine: 3) changes in the gastric mucosal vascular permeability due to chemicals; 4) effect of indomethacin in the ETOH and HCl models with and without surgical vagotomy; 5) changes in the gastric mucosal content of prostacyclin and PGE2 in the ETOH and HCl models after surgical vagotomy; and 6) changes in the role of SH-groups in gastric mucosal defense after surgical vagotomy. It was found that: 1) the gastric mucosal damage produced by chemicals (ETOH, HCl, and indomethacin) was enhanced after surgical vagotomy; 2) the cyto- and general gastric protective effects of β-carotene, prostacyclin, and small doses of atropine and cimetidine disappeared after surgical vagotomy; 3) the vascular permeability due to chemicals (ETOH, HCl, indomethacin) significantly increased after surgical vagotomy in association with an increase in both number and severity of gastric mucosal lesions; 4) IND alone (in animals with an intact vagus) did not produce gastric mucosal lesions (in 1-h experiments), but it aggravated ETOH-induced gastric mucosal damage (both its number and severity); 5) the gastric mucosal levels of prostacyclin and PGE2 decreased after surgical vagotomy; 6) IND application (after surgical vagotomy) decreased further the tissue levels of prostacyclin and PGE2 in association with an increase of gastric mucosal damage; and 7) the gastric mucosal protective effects of SH-groups were abolished by surgical vagotomy. 相似文献
44.
R. Vagnozzi G. Lazzarino B. Tavazzi D. Di Pierro P. Siragusa R. Giuffré B. Giardina 《Biological trace element research》1995,47(1-3):241-246
Short-term incomplete cerebral ischemia was induced in the rat by bilaterally clamping for 5 min the common carotid arteries;
subsequent reperfusion of 10 min was obtained by removing carotid occlusion. At the end of ischemia or reperfusion, animals
were sacrificed by decapitation. A control group was represented by sham-operated rats. Peripheral venous blood samples were
withdrawn from the femoral vein from rats subjected to cerebral reperfusion 5 min before ischemia, at the end of ischemia,
and 10 min after reperfusion. A highly sensitive HPLC method for the direct determination of malondialdehyde, oxypurines,
and nucleosides was used on 200 μL of brain tissue and plasma extracts. Incomplete cerebral ischemia induced the, appearance
of a significant amout of tissue malondialdehyde (undetectable in control animals) and a decrease of ascorbic acid. A further
6.6-fold increase of malondialdehyde and a 18.5% decrease of ascorbic acid occurred after 10 min of reperfusion. Plasma malondialdehyde,
which was present in minimal amount before ischemia, significantly increased after 5 min of ischemia, being strikingly augmented
after 10 min of reperfusion. A similar trend was observed for oxypurines and nucleosides. From these data, it can be affirmed
that tissue concentrations of malondialdehyde and ascorbic acid, and plasma levels of malondialdehyde, oxypurines, and nucleosides,
reflect both the oxygen radical-mediated tissue injury and the depression of energy metabolism thus representing early biochemical
markers of short-term incomplete brain ischemia, and reperfusion in the rat. 相似文献
45.
Exemestane experience in breast cancer treatment 总被引:2,自引:0,他引:2
P. E. Lnning R. Paridaens B. Thürlimann G. Piscitelli E. di Salle 《The Journal of steroid biochemistry and molecular biology》1997,61(3-6):151-155
Exemestane is a very potent, orally active, selective and long-lasting steroidal irreversible inhibitor of aromatase. It is 150 times more potent than aminoglutethimide (AG) in inhibiting human placental aromatase (Ki of 4.3 and 671 nM, respectively). The compound is presently under phase III evaluation in Europe and the U.S.A. for the treatment of postmenopausal advanced breast cancer (ABC). Clinical pharmacology studies have been carried out with single doses ranging from 0.5 to 800 mg and repeated doses of up to 600 mg a day, in 132 postmenopausal healthy volunteers and in 185 post-menopausal women with ABC. Results obtained using a very specific and sensitive analytical method (high performance liquid chromatography—radioimmunoassay; HPLC—RIA) indicated that exemestane is extremely effective in inhibiting plasma estrogens levels. Estrogen inhibition is clearly evident at 5 mg a day and maximal suppression for E2, E1 and E1S (>85%, >90% and>90%, respectively) is obtained at 10–25 mg a day. Data from non-controlled phase II studies involving more than 400 patients indicated a clear anti-tumour activity in postmenopausal ABC patients failing multiple hormonal treatments. In 62 patients progressing on AG (≥500 mg a day) exemestane treatment resulted in an objective response rate of approximately 24%; disease stabilization ≥24 weeks was observed in an additional 24% of cases. With regard to safety, although daily doses up to 600 mg were administered, the maximal tolerated dose was not achieved; reported symptoms were mainly related to the pharmacological action of the compound and were usually mild to moderate in severity, resulting in the discontinuation of therapy in less than 3% of cases. In conclusion, the available results suggest that exemestane treatment is associated with minimal toxicity, and may be of significant benefit for ABC women who have exhausted conventional therapy. 相似文献
46.
Inhibition enzyme-linked immunosorbent assay for detection of Pseudomonas fluorescens on meat surfaces.
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An inhibition enzyme-linked immunosorbent assay was developed for Pseudomonas fluorescens enumeration of meat surfaces. The assay detected contamination levels as low as 3 x 10(5) bacteria per ml and could be completed within 4 h. It could be used as a framework for a test system for quantifying P. fluorescens spoilage in meat products. 相似文献
47.
M. P. Francescato T. Talon P. E. di Prampero 《European journal of applied physiology and occupational physiology》1995,71(4):355-361
Energy costs and energy sources in karate (wado style) were studied in eight male practitioners (age 23.8 years, mass. 72.3 kg, maximal oxygen consumption (VO2max) 36.8 ml · min–1 · kg–1) performing six katas (formal, organized movement sequences) of increasing duration (from approximately. 10 s to approximately 80 s). Oxygen consumption (VO2) was determined during pre-exercise rest, the exercise period and the first 270 s of recovery in five consecutive expired gas collections. A blood sample for lactate (la–) analysis was taken 5 min after the end of exercise. The overall amount of O2 consumed during the exercise and in the following recovery increased linearly with the duration of exercise (t) from approximately 1.51 (for t equal to 10.5 s (SD 1.6)) to approximately 5.81, for t equal to 81.5 s (SD 1.0). The energy release from la– production (VO21a
–) calculated assuming that an increase of 1 mmol · l–1 la– corresponded to a VO2 of 3 mlO2 · kg–1 was negligible for t equal to or less than 20 s and increased to 17.3 ml · kg–1 (la– = 5.8 mmol · l–1 above resting values) for t equal approximately to 80 s. The overall energy requirement (VO2eq) as given by the sum of VO2 and VO2la
– was described by VO2eq = 0.87 + 0.071 · t (n = 64; r
2 = 0.91), where VO2eq is in litres and t in seconds. This equation shows that the metabolic power (VO2eq · t
–1) for this karate style is very high: from approximately 9.51 · min–1 for t equal to 10 s to approximately 4.91 · min–1 for t equal to 80 s, i.e. from 3.5 to 1.8 times the subjects' VO2max. The fraction of VO2eq derived from the amount of O2 consumed during the exercise increased from 11% for t equal to 10 s to 41 % for t equal to 80 s whereas VO21a
– was negligible far t equal to or less than 20 s and increased to 13 % o for t equal to 80 s. The remaining fraction (from 90% for t equal to 10 s to 46% for t equal to 80 s), corresponding to the amount of O2 consumed in the recovery after exercise, is derived from anaerobic alactic sources, i.e. from net splitting of high energy phosphates during the exercise. 相似文献
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49.
A total of 51 restriction sites were recognized within the BK virus genome by the combination of 10 different restriction endonucleases. These sites were mapped and oriented relative to one another as well as to the five fragments generated by the digestion of BK virus DNA with HindIII and EcoRI. The result was a comprehensive physical map suitable for in-depth characterization of the functions of BK virus at the molecular level. 相似文献
50.
C Mangoni di S Stefano M Ruggiero M Brunese S Morelli 《Bollettino della Società italiana di biologia sperimentale》1979,55(14):1398-1404
Metabolic rate of obese patients is reported, recorded to cellular active mass. The metabolic rate is higher in obese patients and the value is diucthy related to individual actual weight. The dinamic-specific action of proteins is normal. 相似文献