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1.
OBJECTIVES: To evaluate the effects of radiation synovectomy (RSYN) with holmium-166 ferric hydroxide macroaggregate (Ho-166 FHMA) on synovium and synovial fluid in normal metacarpo- and metatarsophalangeal joints of horses and to determine intraarticular distribution of radioactivity after Ho-166 FHMA treatment. STUDY DESIGN: Either Ho-166 FHMA or nonradioactive Ho-165 FHMA was injected into metacarpo- or metatarsophalangeal joints. ANIMALS: Six adult mixed-breed horses without any clinical evidence of metacarpo- or metatarsophalangeal joint disease. METHODS: Joints were injected with a single high dose of Ho-166 FHMA (mean, 1,000 MBq/joint) or a nonradioactive Ho-165 FHMA preparation (controls). Clinical examination, arthroscopy, synovial fluid analyses, and histologic studies were performed to detect effects of RSYN. Scintigraphy was used to localize intraarticular distribution of Ho-166 FHMA. RESULTS: Ho-166 FHMA treatment induced joint inflammation leading to regional edema, effusion, and scar tissue formation. Scintigraphy revealed the highest intensity of radioactivity in the proximal plantar joint pouch, at which the Ho-166 FHMA treatment caused multifocal necrosis. In the dorsal joint pouch, however, arthroscopic study and histologic analysis showed very little effect of RSYN. There was no regeneration of synovium evident within 2 months. Synovial fluid protein concentration was significantly (P <.01) elevated, and some residual radioactivity remained for 5 days after Ho-166 FHMA injection. CONCLUSIONS: Injection of a single high dose of Ho-166 FHMA caused multifocal necrosis of synovium and deep, soft-tissue injury in equine fetlock joints. CLINICAL RELEVANCE: Inflamed equine joints with synovial lining hyperplasia could benefit from Ho-166 FHMA-induced radiation synovectomy if excessive scar tissue formation can be avoided.  相似文献   
2.
We investigated the impacts of elevated temperature and carbon dioxide concentration ([CO2]) on diameter growth of Scots pine (Pinus sylvestris L.), aged about 20 years, grown with a low nitrogen supply in closed chambers at (i) ambient temperature and [CO2] (AT+AC), (ii) ambient temperature and elevated [CO2] (AT+EC), (iii) elevated temperature and ambient [CO2] (ET+AC), and (iv). elevated temperature and [CO2] (ET+EC). Each treatment was replicated four times. Diameter growth was monitored with a band dendrograph at 15-min intervals throughout the growing seasons of 1997, 1998 and 1999. Over the monitoring period, diameter growth began 2-3 weeks earlier in trees in the ET+EC and ET+AC chambers than in trees in the AT+AC and AT+EC chambers. However, the cessation of growth occurred about a week later in trees in the ET+EC, ET+AC and AT+EC chambers compared with the AT+AC chambers. The duration of the growing season was 115 and 108 days in the ET+EC and ET+AC chambers, respectively, and 95 and 84 days in the AT+EC and AT+AC chambers, respectively. The ET+AC and ET+EC treatments enhanced diameter growth most early in the growing season, whereas in trees in the AT+AC and AT+EC treatments diameter growth rate was highest in the middle of the growing season. Diameter growth rate leveled off more slowly in trees in the ET+EC and AT+EC treatments than in the other treatments. The growth response to elevated T, elevated [CO2] or both decreased with time and it was less than the maximum observed in other studies for small seedlings and under optimal growth conditions. Nevertheless, cumulative diameter growth for the 3-year period was 67% greater in trees in the ET+EC treatment, and 57 and 26% greater in trees in the AT+EC and ET+AC treatments, respectively, compared with trees in the AT+AC treatment. Over the 3 years, [CO2] had a statistically significant (P < 0.10) effect on both absolute and relative diameter growth, but the interaction between [CO2] and temperature was not significant.  相似文献   
3.
Effects of elevated concentrations of tropospheric ozone ([O3]) and carbon dioxide ([CO2]) on leaves of two silver birch (Betula pendula Roth) clones were monitored for three growing seasons (1998, 1999, 2000) by means of electrical impedance spectroscopy (EIS). The field trial with open-top chambers (OTCs) was conducted on two clones (Clone 4 and Clone 80) with five treatments and four independent replicates. Treatments were: (1) outside control, (2) chamber control, (3) 2x ambient [O3], (4) 2x ambient [CO2] and (5) 2x ambient [CO2] + 2x ambient [O3]. Fumigations started in 1999 and continued in 2000. Measurements were made in 1998 before the fumigations and thereafter EIS was carried out four times in each season. The impedance spectra of about 10 leaves from each tree at each time were measured at 42 frequencies between 80 and 1 MHz. Leaf spectra were modeled by a distributed circuit element model (DCE) (one DCE in series with a resistor), which yields the extracellular and intracellular resistances, the relaxation time and the distribution coefficient of the relaxation time. The EIS properties of the leaves changed significantly during the growing season when new leaves were expanding. The clones differed in their EIS properties. Clone 4 had a significantly higher extracellular resistance and distribution coefficient than Clone 80. The clones responded similarly to the fumigation treatments. Differences between treatments emerged especially during the second fumigation season in 2000. Elevated [O3] reduced both the relaxation time and the extracellular resistance, indicating cell membrane damage. Elevated [CO2] increased the intracellular resistance, indicating changes in symplastic composition. The biological interpretation of the EIS parameters in birch leaves is discussed.  相似文献   
4.
A species trial with 14 eucalypt species with randomized complete blocks design was planted on Imperata cylindrica dominated grassland in South Kalimantan, Indonesia in January 1987. The site was prepared mechanically. No fertilizers were used. At the age of three years E. camaldulensis had clearly the highest survival rate (95%) and mean annual increment (5.9 m3ha–1a–1) compared with the other species tried. It was followed by E. urophylla, E. deglupta, E. pellita, E. tereticornis, E. alba, E. torelliana, E. intermedia, E. grandis and E. pilularis. Four other species, E. phaeotricha, E. resinifera, E. cloeziana and E. microcorys died either in the nursery or immediately after planting. All the eucalypts tried had narrow crowns and open canopies. It is suggested that eucalypts are not recommendable for grassland reforestation under minimum plantation tending. Effects of intensive weeding, spacing, fertilizing and performance in second rotation or mixed stands should be tested to elaborate the suitability of eucalypts on grasslands.  相似文献   
5.
We studied the effects of elevated concentrations of carbon dioxide ([CO2]) and ozone ([O3]) on growth, biomass allocation and leaf area of field-grown O3-tolerant (Clone 4) and O3-sensitive clones (Clone 80) of European silver birch (Betula pendula Roth) trees during 1999-2001. Seven-year-old trees of Clones 4 and 80 growing outside in open-top chambers were exposed for 3 years to the following treatments: outside control (OC); chamber control (CC); 2 x ambient [CO2] (EC); 2 x ambient [O3] (EO); and 2 x ambient [CO2] + 2 x ambient [O3] (EC+EO). When the results for the two clones were analyzed together, elevated [CO2] increased tree growth and biomass, but had no effect on biomass allocation. Total leaf area increased and leaf abscission was delayed in response to elevated [CO2]. Elevated [O3] decreased dry mass of roots and branches and mean leaf size and induced earlier leaf abscission in the autumn; otherwise, the effects of elevated [O3] were small across the clones. However, there were significant interactions between elevated [CO2] and elevated [O3]. When results for the clones were analyzed separately, stem diameter, volume growth and total biomass of Clone 80 were increased by elevated [CO2] and the stimulatory effects of elevated [CO2] on stem volume growth and total leaf area increased during the 3-year study. Clone 80 was unaffected by elevated [O3]. In Clone 4, elevated [O3] decreased root and branch biomass by 38 and 29%, respectively, whereas this clone showed few responses to elevated [CO2]. Elevated [CO2] significantly increased total leaf area in Clone 80 only, which may partly explain the smaller growth responses to elevated [CO2] of Clone 4 compared with Clone 80. Although we observed responses to elevated [O3], the responses to the EC+EO and EC treatments were similar, indicating that the trees only responded to elevated [O3] under ambient [CO2] conditions, perhaps reflecting a greater quantity of carbohydrates available for detoxification and repair in elevated [CO2].  相似文献   
6.
Impacts of elevated temperature and carbon dioxide concentration ([CO2]) on wood properties of 15-year-old Scots pines (Pinus sylvestris L.) grown under conditions of low nitrogen supply were investigated in open-top chambers. The treatments consisted of (i) ambient temperature and ambient [CO2] (AT+AC), (ii) ambient temperature and elevated [CO2] (AT+EC), (iii) elevated temperature and ambient [CO2] (ET+AC) and (iv) elevated temperature and elevated [CO2] (ET+EC). Wood properties analyzed for the years 1992-1994 included ring width, early- and latewood width and their proportions, intra-ring wood density (minimum, maximum and mean, as well as early- and latewood densities), mean fiber length and chemical composition of the wood (cellulose, hemicellulose, lignin and acetone extractive concentration). Absolute radial growth over the 3-year period was 54% greater in AT+EC trees and 30 and 25% greater in ET+AC and ET+EC trees, respectively, than in AT+AC trees. Neither elevated temperature nor elevated [CO2] had a statistically significant effect on ring width, early- and latewood widths or their proportions. Both latewood density and maximum intra-ring density were increased by elevated [CO2], whereas fiber length was increased by elevated temperature. Hemicellulose concentration decreased and lignin concentration increased significantly in response to elevated temperature. There were no statistically significant interaction effects of elevated temperature and elevated [CO2] on the wood properties, except on earlywood density.  相似文献   
7.

Background

Overwintering (breeding) reindeer (Rangifer tarandus tarandus) are commonly treated with ivermectin against parasitic infestations once yearly in autumn-winter roundups. The only preparations registered to reindeer are those for subcutaneous injection. However, also oral extra-label ivermectin administration is used. Twenty-six, 8-month-old reindeer calves were randomly allocated into three groups. Group 1 (n = 9) received oral ivermectin mixture (Ivomec® vet mixt. 0.8 mg/ml, oral ovine liquid drench formulation), Group 2 (n = 9) oral ivermectin paste (Ivomec® vet 18.7 mg/g equine paste), and Group 3 (n = 8) subcutaneous injection of ivermectin (Ivomec® 10 mg/ml vet inj.), each group at a dose of 200 μg/kg body weight. Blood samples were collected at treatment and at days 1, 2, 3, 6, 9 and 16 post treatment. Plasma concentrations of ivermectin were determined by high-pressure liquid chromatography (HPLC) with fluorescence detection.

Results

The peak plasma concentration (Cmax) was reached by 2 days after each treatment. The Cmax and Area Under Curve (AUC) differed significantly between the groups: Cmax was 30.2 ± 3.9, 14.9 ± 5.7 and 63.1 ± 13.1 ng/ml, and AUC was 2881 ± 462, 1299 ± 342 and 6718 ± 1620 ng*h/ml for groups 1, 2 and 3, respectively (mean ± standard deviation).

Conclusions

The differences in plasma concentrations of ivermectin are concomitant with earlier observed differences in antiparasitic efficacy, which discounts the use of the equine paste in reindeer in favour of the oral ovine liquid drench formulation, or preferably, the reindeer-registered subcutaneous injection formulation.  相似文献   
8.
A quantitative genetic analysis was performed to study potential to breed for improved body shape, skin colour and skin spottiness of large rainbow trout in sea and fresh water production environments, and in different stages of growth. The results showed that heritabilities in both production environments were moderate for body shape and skin colour and very high for skin spots. For body shape and skin spots, genetic correlation between the two production environments was high (rA≥0.90), revealing weak genotype‐by‐environment interactions across the environments. For skin colour, genetic correlation between the environments was positive (0.78) but lower than for body shape and skin spots, indicating moderate genotype‐by‐environment interactions. Genetic correlations between 2‐ and 3‐year‐old fish were high for body shape and skin spots (rA≥0.93) and moderate for skin colour (0.85), showing that differences among families persisted strongly during growth. The positive correlations between the environments and between the ages imply that selection in fresh water environment at a single point of time should lead to favourable correlated genetic responses in the sea and at the other stages of growth.  相似文献   
9.
The major wild Atlantic salmon stocks in the Baltic Sea began to recover in the late 1990s. This recovery has been partly due to strict regulations in the Gulf of Bothnia that effectively prevent salmon fisheries during the peak migration. About half of the migrating salmon, however, are reared fish that could be harvested. We simulated a limited trap-net fishery that selectively harvested reared salmon and released wild fish, and studied the survival and migration of the released salmon. We tagged and released 1970 salmon caught in the trap-nets along the coast in 2001 and 2002. The mean maximum capture and release induced mortality of salmon was 11%, ranging between 4% and 21% in different release groups by year, sea age and number of releases. The cumulative mortality for the total salmon population on their spawning migration in the Gulf of Bothnia was below 5%, and it would not increase considerably after the first capture and release events, provided fishing effort is not excessive and fish are handled properly. Survival of trap-net captured and released Baltic salmon appears high and their migration behavior is not altered due to this handling. Several preconditions, however, should be considered before selective fishing is introduced in the Gulf of Bothnia salmon fishery.  相似文献   
10.
The goal of this paper is to propose and evaluate automated image analysis methods for describing muscle cutlets in rainbow trout. The proposed automated image analysis methods were tested on a total of 983 scanned images of trout cutlets, and included quality traits such as fat percentage, flesh colour and the size of morphologically distinguishable subparts of the cutlet. A sub-sample of 50 images was randomly selected for manual segmentation of the cutlet, the dorsal fat depot and the red muscle and regions. The identification of these regions by manual and automatic image analysis correlated strongly (r = 0.97, r = 0.95 and r = 0.91, respectively). The estimated fat percentage obtained from image analysis, based on the area of visible fat and the colour of the cutlet flesh, correlated well with chemical fat percentage measured by mid-infrared transmission spectroscopy (MIT) (r = 0.78). The automated image analysis methods are therefore a reliable means of predicting the fat percentage of trout cutlets. Principal component analysis (PCA) loading plots were used to identify subsets of variables from the image analysis of special significance for further studies; cutlet area, dorsal fat depot area, red muscle area, back height, cutlet width, and width of left and right abdomen wall were among the variables selected. PCA loading plots of different colour variables indicated that simple statistical coefficients such as percentiles and mean values can be used to quantify different aspects of flesh colour. In conclusion, the methods presented here provide a powerful toolbox for describing important morphological structures and quality traits of trout cutlets.  相似文献   
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