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71.
It is becoming increasingly difficult to manage and expand statutory conservation areas (i.e., parks and formally protected areas). Therefore, alternative opportunities for land conservation merit closer attention. This paper examines the extent to which privately owned conservation areas contribute to biodiversity representation. Gap analyses were performed for a large semi-arid region in South Africa with a comprehensive database of private conservation areas. The distribution of private conservation areas was compared to statutory conservation areas using several landscape characteristics: biome and vegetation variant, elevation class, ecological process area, total area, and threat status (endangerment). Conservation target achievement for the vegetation variants was also assessed, as was the degree to which private conservation areas complemented statutory conservation areas by representing different landscape characteristics. The number of targets achieved nearly tripled if private conservation areas were considered in addition to statutory conservation areas. Further, private conservation areas significantly complemented statutory conservation areas in the types of biomes, elevation classes, and threat status classes conserved. Private conservation areas were especially important in conserving lower elevation habitat, and by association, endangered vegetation. This particular relationship is expected to be common worldwide. Our results indicate that private lands conservation deserves an increased allocation of resources for both research and implementation.  相似文献   
72.
Haemophilus parasuis is a colonizer of the upper respiratory tract of healthy pigs, but virulent strains can cause a systemic infection characterized by fibrinous polyserositis, commonly known as Glässer’s disease. The variability in virulence that is observed among H. parasuis strains is not completely understood, since the virulence mechanisms of H. parasuis are largely unknown. In the course of infection, H. parasuis has to survive the host pulmonary defences, which include alveolar macrophages, to produce disease. Using strains from different clinical backgrounds, we were able to detect clear differences in susceptibility to phagocytosis. Strains isolated from the nose of healthy animals were efficiently phagocytosed by porcine alveolar macrophages (PAM), while strains isolated from systemic lesions were resistant to this interaction. Phagocytosis of susceptible strains proceeded through mechanisms independent of a specific receptor, which involved actin filaments and microtubules. In all the systemic strains tested in this study, we observed a distinct capsule after interaction with PAM, indicating a role of this surface structure in phagocytosis resistance. However, additional mechanisms of resistance to phagocytosis should be explored, since we detected different effects of microtubule inhibition among systemic strains.  相似文献   
73.
The relationship between early root and shoot formation at the beginning of the vegetation period and cutting survival on sandy and loamy fluvisol for 14 genotypes of black poplars was analyzed. Considerable cutting mortality was observed only within the first 80 days since planting. Intensive root formation in the first 20 days since the planting and vigorous shoot growth and development in subsequent 20 days was observed in easy-to-root genotypes. Coefficients of correlation revealed close relationship between early root and shoot growth and development and cutting survival of tested genotypes. The obtained results could be used in the breeding process, as well as for the design of cultivar-adjusted nursery and plantation establishment technology. Tested shoot characteristics, were found to be especially interesting since they could be measured rapidly, by non-destructive means.  相似文献   
74.
A new iridoid diglucoside, 10-O-(E)-p-coumaroylmelittoside (1) and a new flavone glucoside, O-(6'-O-Acetyl-)-beta-glucopyranosylchrysoeriol (2), together with four known flavone glycosides, were isolated from the aerial parts of Sideritis lanata. The structures of the new compounds were elucidated by spectroscopic methods, 2D NMR and MS.  相似文献   
75.
The mechanical properties and responses of cells to external stimuli (including drugs) are closely connected to important phenomena such as cell spreading, motility, activity, and potentially even differentiation. Here, reversible changes in the viscoelastic properties of surface-attached fibroblasts were induced by the cytoskeleton-perturbing agent cytochalasin D, and studied in real-time by the quartz crystal microbalance with dissipation (QCM-D) technique. QCM-D is a surface sensitive technique that measures changes in (dynamically coupled) mass and viscoelastic properties close to the sensor surface, within a distance into the cell that is usually only a fraction of its size. In this work, QCM-D was combined with light microscopy to study in situ cell attachment and spreading. Overtone-dependent changes of the QCM-D responses (frequency and dissipation shifts) were first recorded, as fibroblast cells attached to protein-coated sensors in a window equipped flow module. Then, as the cell layer had stabilised, morphological changes were induced in the cells by injecting cytochalasin D. This caused changes in the QCM-D signals that were reversible in the sense that they disappeared upon removal of cytochalasin D. These results are compared to other cell QCM-D studies. Our results stress the combination of QCM-D and light microscopy to help interpret QCM-D results obtained in cell assays and thus suggests a direction to develop the QCM-D technique as an even more useful tool for real-time cell studies.  相似文献   
76.
This review covers both physical and chemical modifications of cellulose fibre surface and their impact on the properties of the ensuing papers. It is not restricted to actual industrial operations, but also deals instead with ongoing research in this area, which appears promising in terms of possible applications to papermaking.  相似文献   
77.
78.
A 15‐year‐old, neutered male, Shih Tzu cross developed progressive corneal stromal thickening and vascularization of the right eye, and 5 months later, of the left eye. Both eyes became blind due to extensive corneal opacification and were enucleated. Light microscopic examination revealed a diffuse corneal infiltrate of neoplastic mesenchymal cells, and immunohistochemistry revealed diffuse cytoplasmic vimentin immunoreactivity and variable cytoplasmic and nuclear immunoreactivity for S100 in the neoplastic cells. Transmission electron microscopy revealed desmosomes between contiguous cells, thread‐like cytoplasmic processes coated with basement membrane, extracellular bundles of collagen, and axonal degeneration consistent with features of a nerve sheath neoplasm. This is the first report of primary, bilateral corneal nerve sheath sarcoma in a canine.  相似文献   
79.

Objective

To evaluate the onset, magnitude and duration of thermal antinociception after oral administration of two doses of tapentadol in cats.

Study design

Prospective, randomized, blinded, experimental study.

Animals

Six healthy adult cats weighing 4.4 ± 0.4 kg.

Methods

Skin temperature (ST) and thermal threshold (TT) were evaluated using a wireless TT device up to 12 hours after treatment. Treatments included placebo (PBO, 50 mg dextrose anhydrase orally), buprenorphine (BUP, 0.02 mg kg?1) administered intramuscularly, low-dose tapentadol (LowTAP, 25 mg orally; mean 5.7 mg kg?1) and high-dose tapentadol (HighTAP, 50 mg orally; mean 11.4 mg kg?1) in a blinded crossover design with 7 day intervals. Statistical analysis was performed using anova with appropriate post hoc test (p ≤ 0.05).

Results

Salivation was observed immediately following 11 out of 12 treatments with tapentadol. The ST was significantly increased at various time points in the opioid treatments. Hyperthermia (≥ 39.5 °C) was not observed. Baseline TT was 45.4 ± 1.4 °C for all treatments. Maximum TT values were 48.8 ± 4.8 °C at 1 hour in LowTAP, 48.5 ± 3.0 °C at 2 hours in HighTAP and 50.2 ± 5.3 °C at 1 hour in BUP. TT significantly increased after LowTAP at 1 hour, after HighTAP at 1–2 hours, and after BUP at 1–2 hours compared with baseline values. TTs were significantly increased in BUP at 1–2 hours compared with PBO.

Conclusion and clinical relevance

Oral administration of tapentadol increased ST and TT in cats. The durations of thermal antinociception were similar between HighTAP and BUP, both of which were twice as long as that in LowTAP. Studies of different formulations may be necessary before tapentadol can be accepted into feline practice.  相似文献   
80.
In order to extend scientific knowledge on autochthonous Italian equine meat, the physical–chemical parameters of Catria Horse Longissimus thoracis (LT) muscle and its nutritional characteristics have been investigated. Ten steaks of Catria foal raised at pasture and fattened indoors for 2 months were dissected, and LT muscle was analyzed for chemical composition, total iron, drip loss, colorimetric characteristics, intramuscular fat, fatty acid profile and nutritional indexes. Steak dissection showed that LT muscle accounted for 36.78% and fat accounted for 9.19% of weight of steak. Regarding chemical composition, protein and fat content was 20.31% and 2.83%, respectively. Total iron content (1.95 mg/100 g) was lower than data reported in the literature. Color parameters showed a luminous and intense red hue muscle. The sum of unsaturated fatty acid composition (50.3%) was higher than the sum of saturated fatty acids (46.64 %). The fatty acid profile and nutritional values of Catria Horse meat could be modified adopting extensive rearing systems and grazing. The data suggests that further investigation on the composition of Catria Horse meat should be carried out to valorize this autochthonous breed, reared in sustainable livestock systems, and its meat in local short‐chain systems.  相似文献   
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