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51.
52.
Antioxidant compounds and antioxidant activity in "early potatoes"   总被引:1,自引:0,他引:1  
The antioxidant content and the antioxidant capacity of both hydrophilic and lipophilic antioxidant extracts from four "early potato" cultivars, grown in two different locations (Racale and Monteroni), were examined. There was a considerable variation in carotenoid content and weak differences in the ascorbic acid concentration of the examined cultivars of "early potato" and between the harvested locations. An increase in both methanol/water (8:2 v/v) and phosphate buffer soluble (PBS) free phenols (70%) and bound phenols (28%) in the extracts from the cultivars grown at Racale site was found and discussed. Examination of individual phenols revealed that chlorogenic acid and catechin were the major phenols present in potato tuber extracts; a moderate amount of caffeic acid and ferulic acid was also detected. The total equivalent antioxidant capacity (TEAC) was higher in the Racale extracts and a highly positive linear relationship ( R (2) = 0.8193) between TEAC values and total phenolic content was observed. The oxyradical scavenging capacity (TOSC) of methanol/water and PBS extracts of peel and whole potatoes against the reactive oxygen species (ROS) peroxyl radicals, peroxynitrite, and hydroxyl radicals was also analyzed. A highly significant linear correlation ( R (2) = 0.9613) between total antioxidant capacity (as a sum of peroxyl radicals + peroxynitrite) and total phenol content of methanol/water extracts was established. Moreover, proliferation of human mammalian cancer (MCF-7) cells was significantly inhibited in a dose-dependent manner after exposure to potato extracts. These data can be useful for "early potato" tuber characterization and suggest that the "early potato" has a potential as a dietary source of antioxidants.  相似文献   
53.
This study aimed to evaluate the analgesic efficacy of gabapentin as an adjuvant for postoperative pain management in dogs. Twenty dogs undergoing mastectomy were randomized to receive perioperative oral placebo or gabapentin (10 mg/kg). All dogs were premedicated with intramuscular acepromazine (0.03 mg/kg) and morphine (0.3 mg/ kg). Anesthesia was induced with propofol (4 mg/kg) intravenously and maintained with isoflurane. Intravenous meloxicam (0.2 mg/kg) was administered preoperatively. Postoperative analgesia was evaluated for 72 hr. Rescue analgesia was provided with intramuscular morphine (0.5 mg/kg). Dogs in the Placebo group received significantly more morphine doses than the Gabapentin group (P=0.021), despite no significant differences in pain scores. Perioperative gabapentin reduced the postoperative morphine requirements in dogs after mastectomy.  相似文献   
54.
55.

Context

Landscape-scale population dynamics are driven in part by movement within and dispersal among habitat patches. Predicting these processes requires information about how movement behavior varies among land cover types.

Objectives

We investigated how butterfly movement in a heterogeneous landscape varies within and between habitat and matrix land cover types, and the implications of these differences for within-patch residence times and among-patch connectivity.

Methods

We empirically measured movement behavior in the Baltimore checkerspot butterfly (Euphydryas phaeton) in three land cover classes that broadly constitute habitat and two classes that constitute matrix. We also measured habitat preference at boundaries. We predicted patch residence times and interpatch dispersal using movement parameters estimated separately for each habitat and matrix land cover subclass (5 categories), or for combined habitat and combined matrix land cover classes (2 categories). We evaluated the effects of including edge behavior on all metrics.

Results

Overall, movement was slower within habitat land cover types, and faster in matrix cover types. Butterflies at forest edges were biased to remain in open areas, and connectivity and patch residence times were most affected by behavior at structural edges. Differences in movement between matrix subclasses had a greater effect on predictions about connectivity than differences between habitat subclasses. Differences in movement among habitat subclasses had a greater effect on residence times.

Conclusions

Our findings highlight the importance of careful classification of movement and land cover in heterogeneous landscapes, and reveal how subtle differences in behavioral responses to land cover can affect landscape-scale outcomes.
  相似文献   
56.
Canine generalised demodicosis (GD) can be difficult to cure, with some dogs requiring life-long treatment. The aim of this pilot study was to evaluate the effectiveness of monthly 10 per cent moxidectin/2·5 per cent imidacloprid spot-on in maintaining long-term (12 months) clinical and parasitological remission in dogs with relapsing GD. Fourteen dogs were included: 10 with juvenile-onset GD (JOGD) and four with adult-onset GD (AOGD). All?dogs had been treated previously and relapsed (1-4 times). Each dog was treated again with either milbemycin oxime 2 mg/kg or ivermectin 400 μg/kg orally once daily, until two consecutive negative skin scrapings at one-month intervals (total 4-7 months of treatment). After treatment discontinuation, 10 per cent moxidectin/2·5 per cent imidacloprid spot-on was applied monthly for 12 months. Dogs were rechecked after 1, 2, 3, 6 and 12 months, and multiple skin scrapings were taken. Twelve dogs completed the study and were clinically normal and parasitologically negative at each recheck (four dogs with AOGD and eight with JOGD). One dog died suddenly for unrelated reasons, and one dog relapsed. Results of this pilot study suggest that monthly application of 10 per cent moxidectin/2·5 per cent imidacloprid spot-on may be effective as maintenance therapy in relapsing cases of GD.  相似文献   
57.
Corona  Piermaria  Leone  Vittorio  Saracino  Antonio 《New Forests》1998,16(3):213-220
Aleppo pine stands account for a third of the burned forests in the Mediterranean basin. The early assessment of post-fire regeneration is essential for the management of such stands. The assessment should be based on reliable and objective methods. In the Mediterranean basin, plot size and shape applied in regeneration survey designs and sampling schemes differ considerably. A study involving twelve stands (7 unharvested and 5 harvested) in the Province of Taranto (southern Italy) was carried out 38 months after a fire, by comparing plots of different shape and size within a plot-count sampling frame. The relative efficiency method was used to compare the efficiency of each size and shape. Early regeneration of Aleppo pine proved to be best assessed by 8m × 2m plots, i.e. by a plot size four times wider than the most commonly used one (2m × 2m). The need for such wide plots depends upon the typical spatial arrangement of the seedlings whose clustering is associated with the presence of seed bearing trees.  相似文献   
58.
Depressed performance and availability of some amino acids (AA) in pigs fed excess Leu diets appear to be related to lower feed intake. Surplus Ile and Val may help to overcome this effect. An experiment was conducted with 24 pigs (31.8 ± 1.2 kg initial BW) to evaluate the effect of dietary excess of either Leu alone or with surplus Ile and Val on performance and serum concentration (SC) of essential AA. Treatments were as follows: T1, basal diet; T2, basal plus 0.43% L‐Leu (excess Leu); T3, basal added with 0.43% L‐Leu, plus 0.20% L‐Ile and 0.25% L‐Val (excess LIV). The basal diet was formulated to contain 0.90% standardized ileal digestible Lys and added with crystalline L‐Lys, L‐Thr, DL‐Met, L‐Trp, L‐Leu, L‐Ile, L‐His and L‐Val to create essential AA:Lys ratios close to an ideal protein for growing pigs. All pigs were fed the same amount of feed twice a day (average, 3.42× the requirement of NEm). Blood samples were collected at 2.5 (absorptive) and 11.0 h (post‐absorptive) post‐prandial to analyse SC of AA. Excess of either Leu or LIV did not affect growth rate nor feed conversion. Excess Leu increased Leu SC and decreased Ile and Val SC (p < 0.05) at both absorptive and post‐absorptive phases, but excess LIV restored the SC of Ile and Val. The SC of other essential AA was not affected by excess of either Leu or LIV. The SC of all AA during absorptive, on average, was about two times higher than that of post‐absorptive phase. These results suggest that the reduced availability (SC) of Ile and Val in pigs consuming excess Leu diets is attributed to a reduced absorption and increased cellular degradation rates of them.  相似文献   
59.

Background

A broad range of gemcitabine dosages have been used in dogs.

Hypothesis/Objectives

To determine maximally tolerated dose (MTD), dose‐limiting toxicity (DLT), and preliminary antitumor activity of intravenous administration of gemcitabine in dogs with advanced solid tumors.

Animals

Twenty‐two client‐owned dogs.

Methods

Dogs with advanced cancer were prospectively enrolled in an open‐label Phase 1 study of gemcitabine. Gemcitabine was administered as a 30‐minute intravenous bolus starting at 800 mg/m2, using escalation of 50 mg/m2 increments with 3 dogs per dose level. MTD was established based on the number of dogs experiencing DLT assessed after 1 cycle. Treatment continued until disease progression or unacceptable toxicosis. Additional dogs were enrolled at MTD to better characterize tolerability, and to assess the extent and duration of gemcitabine excretion.

Results

Twenty‐two dogs were treated at 4 dose levels, ranging from 800 to 950 mg/m2. Neutropenia was identified as DLT. MTD was 900 mg/m2. DLT consisting of grade 4 febrile neutropenia was observed at 950 mg/m2 in 2 dogs. There were no nonhematologic DLTs. Twenty dogs received multiple doses, and none had evidence of severe toxicosis from any of their subsequent treatments. At 900 mg/m2, 2 complete and 5 partial responses were observed in dogs with measurable tumors. The amount of gemcitabine excreted in urine decreased over time, and was undetectable after the first 24 hours.

Conclusions and Clinical Importance

The recommended dose of gemcitabine for future Phase 2 studies is weekly 900 mg/m2. In chemotherapy‐naïve dogs with advanced solid tumor this dose level merits further evaluation.  相似文献   
60.
Adsorption of imazapyr (IMZ), imazethapyr (IMZT), and imazaquin (IMZQ) was studied on two smectite-humic acid and two smectite-ferrihydrite binary systems prepared by treating a Wyoming smectite with a humic acid extracted from soil (4 and 8% w/w of the smectite) and with just-precipitated synthetic ferrihydrite (8 and 16% w/w of the smectite). Adsorption of the three herbicides on the smectite was not measurable at pH >4.5, presumably because of negative charges on the surface of the smectite. Adsorption on the smectite-humic acid systems was also not measurable, presumably because of negative charges on the surface, despite the high affinity of the three herbicides for humic acid, the adsorption order of which was IMZ < IMZT < IMZQ. Adsorption decreased in the order IMZ < IMZT < IMZQ on the smectite-ferrihydrite systems and IMZQ < IMZT < IMZ on ferrihydrite, although here the differences were small. These results show that even though pure smectite cannot adsorb herbicides, it modifies the adsorption capacity of ferrihydrite. The mutual interaction of active phases such as humic acid, ferrihydrite, and smectite alters the characteristics of the resulting surface and hence the adsorption process. Investigations of herbicide adsorption have been seen to produce more reliable results if conducted on polyphasic systems rather than on single soil components.  相似文献   
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