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41.
Forty-eight dogs with histologically confirmed appendicular osteosarcoma (OSA) entered a prospective clinical trial evaluating treatment with amputation and up to 4 doses of carboplatin given every 21 days. The median disease-free interval (DFI) was 257 days, with 31.2% of the dogs disease-free at 1 year. The median survival time was 321 days, with 35.4% of the dogs alive at 1 year. Dogs with proximal humeral OSA had shorter DFI (P = .016) and survival (P = .037) times than dogs with OSA at other locations. Dogs with lower body weights (40 kg) had longer DFI (P = .0056) and survival (P = .007) times than larger dogs. Survival times for dogs that received carboplatin were statistically longer than those previously reported for amputation alone (P < .001). DFI and survival times are similar to those previously reported for 2 to 4 doses of cisplatin. Carboplatin appears to be a well-tolerated chemotherapeutic drug that can be given safely every 21 days at a dose of 300 mg/m2. Neutropenia was the dose-limiting toxicity in this study. J Vet Intern Med 1996;10:76–81. Copyright © 1996 by the American College of Veterinary Internal Medicine .  相似文献   
42.

Context

Loss and fragmentation of semi-natural grasslands has critically affected many butterfly species in Europe. Habitat area and isolation can have strong effects on the local biodiversity but species may also be strongly affected by the surrounding matrix.

Objectives

We explored how different land cover types in the landscape explained the occurrence of butterfly species in semi-natural grasslands.

Methods

Using data from 476 semi-natural grasslands in Sweden, we analysed the effect of matrix composition on species richness and occurrence. Additionally, we analysed at which spatial scales butterflies responded to matrix types (forests, semi-natural grasslands, arable land and water).

Results

Forest cover showed the strongest positive effect on species richness, followed by semi-natural grasslands. Forest also had a positive effect on red-listed species at local scales. Responses to matrix composition were highly species-specific. The majority of the 30 most common species showed strong positive responses to the amount of forest cover within 200–500 m. There was a smaller group of species showing a positive response to arable land cover within 500–2000 m. Thirteen species showed positive responses to the amount of semi-natural grasslands, generally at larger scales (10–30 km).

Conclusions

Our study showed that surrounding forest is beneficial for many grassland butterfly species and that forests might mitigate the negative effects of habitat loss caused by agricultural intensification. Also, semi-natural grasslands were an important factor for species richness at larger spatial scales, indicating that a landscape consisting mainly of supporting habitats (i.e. forests) are insufficient to sustain a rich butterfly fauna.
  相似文献   
43.
44.
Abstract – The possibility to increase the proportion of migrating hatchery‐reared smolts by reducing their food ration was studied. Lake‐migrating, hatchery‐reared salmon (Salmo salar) and trout (Salmo trutta) smolts were either fed normal rations, based on recommendations from the fish‐farming industry, or reduced (15–20%) rations. They were released into the River Klarälven, western Sweden, and followed as they swam downstream to Lake Vänern, a distance of around 25 km. For both Atlantic salmon and brown trout, smolts fed a reduced ration migrated faster than fish fed a normal ration. Furthermore, a higher proportion of salmon smolts fed reduced rations migrated to the lake than fish fed normal rations in 2007 but not in 2006. This difference between years corresponded to greater treatment differences in size and smolt status in 2007 than in 2006. For trout, the proportion of migrating individuals and smolt development did not differ with ration size. Trout migrants fed a normal ration had a higher standard metabolic rate (SMR) than nonmigrants, whereas there was no difference in SMR between migrating and nonmigrating salmon. These results show that it is possible to use a reduced food ration to increase the migration speed of both Atlantic salmon and brown trout and to increase the proportion of migrating Atlantic salmon.  相似文献   
45.
46.
OBJECTIVES: To determine whether clomipramine differs from fluoxetine in reducing feline urine marking; whether reduction of marking continues in cats treated >8 weeks; whether recurrence of marking, after abrupt drug withdrawal, is less in cats treated >8 weeks; and whether cats that are successfully treated but resume marking after drug withdrawal can be successfully treated again with the same drug regimen. DESIGN: Positive-controlled, double-masked clinical trial. ANIMALS: 22 neutered cats (2 females, 20 males) > or =1 year old with objectionable urine marking. PROCEDURE: Cats that marked vertically > or =3 times/wk were treated with fluoxetine (1 mg/kg [0.45 mg/lb], q 24 h, PO) or clomipramine (0.5 mg/kg [0.23 mg/lb], q 24 h, PO) for 16 weeks, and efficacy was compared. Recurrence of marking was determined after abrupt withdrawal of fluoxetine at 16 or 32 weeks. Reduction in marking in cats treated with fluoxetine for 8 weeks after returning to marking following drug withdrawal was compared with the initial 8 weeks of successful treatment. RESULTS: Efficacy of fluoxetine and clomipramine was similar. Treatment >8 weeks revealed increasing efficacy in reduction of marking. Return of marking after termination of fluoxetine administration occurred in most cats. Cats successfully treated initially with fluoxetine responded similarly to repeated treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Clomipramine and fluoxetine were equivalent in treating urine marking. Longer treatment increased efficacy. Most cats return to marking after abrupt drug withdrawal. A second course of treatment can be expected to be as effective as the first.  相似文献   
47.
Introduction: The Patnaik grading system for canine cutaneous MCT is currently one of the best determinants of prognosis; however, clinical outcome does not always correlate with histologic grade. The development of molecular markers offers a potential advantage and may complement subjective grading. The primary purpose of this study was to correlate histologic grading to Ki67/PCNA/AgNOR/c‐Kit scores. Methods: Thirty‐eight dogs with cutaneous MCT underwent surgical resection. Tumors were graded, with expansion of grade II MCT to low, medium (or II only) and high. For statistical purposes, MCT grade I, II (low, medium, high) and III were assigned a score of 1, 2, 3, 4, or 5, respectively. Sections were processed for AgNOR staining and expression of PCNA, Ki67 and c‐Kit as previously described (modified biotin‐strepavidin with DAB substrate). Paraffin‐embedded canine tissue arrays were used as positive and negative controls (primary antibody replaced with pre‐immune sera). Parametric statistical testing was performed using Statview statistical software with P ≤ .05 as significant. Results: There were 12, 20, 5 and 1 grade II low, grade II medium, grade II high and grade III MCT, respectively. The mean Ki67 score was 9.114 (median 8.0, range 1–28), mean PCNA score was 26.25 (median 24.0, range 5–65), mean AgNOR score was 1.499 (median 1.35, range 1.02–2.76) and c‐Kit scores were +1 (9/37), +2 (19/37) and +3 (9/37). With parametric statistical testing, significantly positive correlations were found for Ki67/Grade, PCNA/Grade, AgNOR/Grade, Ki67/PCNA, Ki67/AgNOR and PCNA/AgNOR (all P < .0001). No significant correlation was found for c‐Kit and grade; however, +3 c‐Kit scores had statistically significantly higher grades than +2 c‐Kit scores (P = .0458). Conclusions: Ki67/PCNA/AgNOR scores are positively correlated to grade in dogs with MCT. Further studies to correlate Ki67/PCNA/AgNOR/c‐Kit scores with clinical variables are ongoing.  相似文献   
48.
Carcinomatosis, sarcomatosis and mesothelioma, with or without malignant effusions, are difficult to treat and generally carry a poor prognosis. The purpose of this study was two‐fold; first, to determine the prognosis for dogs with carcinomatosis, sarcomatosis, or mesothelioma, with or without malignant effusions; second, to evaluate the safety and efficacy of treatment with intracavitary (IC) carboplatin and mitoxantrone in dogs with these syndromes. Nineteen dogs were evaluated. Seven were untreated and 12 were treated with IC chemotherapy (mitoxantrone and/or carboplatin), and multiple factors were analysed for significance with respect to survival time. The median survival time (MST) for untreated dogs was 25 days, whereas the MST for treated dogs was 332 days (Log Rank, P < 0.0001). Treatment with IC chemotherapy was well tolerated. This study suggests that IC chemotherapy with mitoxantrone and/or carboplatin is an effective treatment for dogs with carcinomatosis, sarcomatosis or mesothelioma, with or without malignant effusion.  相似文献   
49.
Hydrolytic rancidity makes rice bran unsuitable for human consumption, restricting its use to animal feed. To better understand this lipolytic process, bran from rice cultivars ‘Cypress’ and ‘Earl’ differing in oil concentration (23.5 and 18.3 mg of triacylglycerol/100 mg of bran, respectively) was stored at room temperature for five months, and the changes in triacylglycerol content and fatty acid composition, as well as the accumulation of free fatty acids (FFA) were followed. The decomposition of triacylglycerols displayed a decay pattern, with Cypress showing a more elevated degradation rate when compared with Earl. At day 36, both lines reached the same oil concentration, but the triacylglycerol decomposition in Cypress was still higher, indicating that oil concentration may not be a significant factor affecting the intensity of the rancidity process. The higher degradation rate observed in Cypress was apparently caused by higher lipase activity, which was 26% higher (P < 0.001). Fatty acid composition of triacylglycerols changed during storage, the palmitic acid percentage was similarly reduced in both lines to ≈80% of its initial concentration. Oleic and linoleic acids remained almost unmodified or slightly increased. The final content of FFA was ≈58% higher in Cypress than in Earl (P < 0.001). In conclusion, lipase activity appears to be an important factor determining the intensity of the hydrolytic process, but further research is required to confirm this conjecture. If this hypothesis is verified, a selection for lower lipase activity could be useful for increasing rice bran stability.  相似文献   
50.
The aim of this study was to investigate the effect of bexagliflozin on glycemic control in poorly regulated diabetic cats and to evaluate for adverse events associated with this medication.Sodium-glucose cotransporter 2 inhibitors are a newer class of drugs used in the management of humans with type 2 diabetes mellitus. The objective of this study was to evaluate the effect of the orally administered drug, bexagliflozin in a group of poorly regulated diabetic cats over a 4-week study period. Five client-owned cats with poorly controlled diabetes mellitus receiving insulin therapy were enrolled. Bexagliflozin was administered once daily. Serum fructosamine, serum biochemistry profile, and 10-hour blood glucose curves were assessed at baseline (Day 0), Day 14, and Day 28. All cats had a significant reduction in insulin dose requirement (P = 0.015) and insulin was discontinued in 2 cats. There was a significant decrease in blood glucose concentration obtained from blood glucose concentration curves during the study period (P = 0.022). Serum fructosamine decreased in 4 of the 5 cats with a median decrease of 152 μmol/L (range: 103 to 241 μmol/L), which was not statistically significant (P = 0.117). No cats had any documented episodes of hypoglycemia. Adverse effects were mild. The addition of bexagliflozin significantly improved diabetic management in this group of cats.  相似文献   
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