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1.
Domestic gardens contribute substantially to green spaces in cities, where urbanization removes and fragments natural landscapes, causing the loss of biodiversity and the homogenization of biota. We analyzed the diversity and composition of the flora of 70 domestic gardens in seven localities in Bogotá, Colombia, which represent different periods of expansion of the city. Floristic composition and diversity were related to the origin and use of plants, the urbanization history, and the income of owners. We recorded 4110 individuals belonging to 238 species. The mean species richness per garden was 15.4, with older localities having significantly higher species richness. The similarity among the localities, which evaluated the distinctness of assemblages, ranged from 0.42 to 0.50. Plants from the Neotropical region and exotic plants were the most abundant in all gardens. The most common use was ornamental, and use depended on the socioeconomic status of the owner. The lower-income homes cultivated larger proportions of edible and medicinal plants. Gardens at the oldest localities, with the largest number of native species, contribute to the conservation of flora because they contain the largest number of native species. Furthermore, domestic gardens are good sources of employment for gardeners and are useful places to keep senior citizens active, helping these citizens relieve stress, maintain good health and teach young people the cultural uses of plants. The receptivity of the homeowners to the study opens the door to future research and conservation programs in the city.  相似文献   

2.
Chestnut stands (orchards and coppices) are among the most typical elements of the southern European mountain landscape and a protected habitat (9260 Castanea sativa woods) according to the European Union (Directive 92/43/EEC). As an anthropogenic landscape, they require specific measures to address preservation or to guide their evolutionary trend. In the Northern Apennines, a landscape multiscalar-multitemporal approach was adopted to highlight factors that have acted on the evolution of this habitat and which still might affect either its preservation or its evolutionary dynamics. Using a diachronic GIS-approach, we analyzed old cadastral maps (drawn up 200 years ago), and aerial photographs. Both the present distribution pattern of the woody species and the incidence of important chestnut diseases were also surveyed. The factors explaining the current extent and species composition of the local chestnut forests confirm their status as an anthropogenic habitat. The present landscape distribution of chestnut woods is heavily linked to past human settlements. Chestnut blight and ink disease are more an indirect reason for past felling activities than an actual direct cause of damage to trees, because of the hypovirulence spread and the limited incidence of the ink disease. Vegetation dynamics of abandoned chestnut forests evolved only partly towards deciduous Beech and Hop Hornbeam stands, thus suggesting both the possibility of a recovery of this cultivation and the need for new criteria for its management.  相似文献   

3.
AIM: To explore the expression and activation of matrix metalloproteinase-9 (MMP-9) from monocyte-derived macrophages induced by tumor necrosis factor-α (TNF-α) and to investigate its association with progression of joint damage in patients with rheumatoid arthritis. METHODS: TNF-α and MMP-9 in serum and synovial fluid from patients with early RA and controls were tested with a double-antibody enzyme-linked immunosorbent assay. The correlation between MMP-9 and Larsen score over the first 12 months was analyzed. THP-1 cells differentiated by the treatment with TPA were stimulated with increasing concentration of TNF-α for 24 h in vitro. The protein expression of MMP-9 was determined by Western blotting. The activity of MMP-9 was measured by gelatinolytic zymography. Boyden chamber-matrigel in vitro invasion assay was used to detect the invasive capacity. RESULTS: The levels of TNF-α and MMP-9 in serum and synovial fluid of RA patients were significantly higher than those in controls (P<0.05). Serum and synovial fluid levels of MMP-9 correlated significantly with Larsen score (r=0.37 and 0.32, P<0.01). The MMP-9 activity and invasive ability of co-cultured THP-1 cells with TNF-α and TPA were higher than those of non-TNF-α treatment. CONCLUSION: TNF-α upregulates MMP-9 activation and promotes infiltration of monocyte-derived macrophages, indicating that TNF-α play an important role in the pathogenesis of RA.  相似文献   

4.
AIM:To investigate the role of NF-κB in pentetrazole-induced repeated seizure in developing rats with the inhibitor of NF-κB pyrrolidine dithiocarbamate (PDTC). METHODS:10-day-old Wistar rats (n=72) were prepared for epilepsy model and divided into three groups at random: the PTZ group, the PDTC+PTZ group and the control group. The behavioral changes, the cells morphology and neurons counts in hippocampus, the expression of NF-κB, BrdU (5-bromo, 2-deoxyuridine) immunoreactive cells in hippocampus and the mossy fiber sprouting were observed.RESULTS:(1) The NF-κB expressed in PTZ group was significantly higher than that in PDTC+PTZ group and control group (P<0.01). (2) The dentate gyrus granule cell count in PTZ group was significantly higher than that in control group (P<0.05). In PDTC+PTZ group cell counts in CA1, CA3 and hilar region were significantly lower than those in PTZ group (P<0.05). (3) The BrdU-immunoreactive cells counts in dentate gyrus in PTZ group and PDTC+PTZ group were significantly higher than those in control group (P<0.01), but in PDTC+PTZ group BrdU-immunoreactive cell count was significantly lower than that in PTZ group (P<0.01). Correlate analyzes between NF-κB expression and BrdU-immunoreactive cell counts/granule cell counts showed positive correlation (P<0.01). (4) The mossy fiber sprouting in both PTZ and PDTC+PTZ group was observed. However, the degrees of sprouting showed no significant differences between two groups. CONCLUSION:NF-κB plays a crucial role in epilepsy of developing rats. It encourages neurogenesis and protects neurons in hippocampus, but has no significant effect on mossy fiber sprouting.  相似文献   

5.
6.
AIM:To study the protective effect of hyperpolarized cardioplegic arrest on reperfused rat heart performance and to investigate the role of mitochondrial ATP-sensitive K+ channels (mitoKATP) opening in the protection of hyperpolarized cardioplegia against ischemia/reperfusion damage. METHODS:Forty Sprague-Dawley rats were randomized into five groups (n=8 in each group): control group (Con); depolarized arrest group (D); hyperpolarized arrest group (H); depolarized cardioplegia with 5-hydroxydecanoate (5-HD) group (5HD+D); hyperpolarized cardioplegia with 5-HD group (5HD+H). The rat hearts were quickly removed to Langendorff apparatus. The heart perfusion was performed for 20 min with 37 ℃ Krebs-Henseleit buffer balanced with gas mixture (O2∶〖KG-*2〗CO2=95%∶〖KG-*2〗5%) at 5.8 kPa perfusion pressure, then cardial arrest was induced by different cardioplegic solution. Hearts were subjected to ischemia at 37 ℃ for 40 min followed by 30 min reperfusion. (1) The hemodynamics was detected at recovery after 30 min reperfusion. (2) Before ischemia and at the end-reperfusion, tissue was harvested for mitochondrial isolation and ultrastructure was observed by transmission electron microscopy (TEM). (3) Production of reactive oxygen species (ROS) was also determined at different time points. RESULTS:(1) Compared with end-equilibration, 30 min reperfusion caused significant differences in left ventricular developed pressure (LADP), left ventricular end-diastolic pressure (LVEDP), double product (DP), heart rate (HR), coronary flow (CF) (P<0.01). TEM showed that the ultrastructures of myocardial and mitochondrial were damaged remarkably. (2) When H group was compared with D, 5HD+H and Con group, significant differences were found in LVDP, LVEDP, DP, HR and CF (P<0.01). TEM showed that the myocardial and mitochondrial ultrastructures were improved remarkably. (3) The rate of ROS generating was lower in group H than that in other four groups at end-reperfusion (P<0.01). CONCLUSION:(1) Of the four cardioplegias, hyperpolarized cardioplegia is superior to improve myocardial performance, attenuates myocardial and mitochondrial injury, and reduces rate of ROS generating. (2) Mitochondrial preservation is one of mechanisms of myocardial protection in hyperpolarized cardioplegia, opening of mitoKATP enhances cardioprotection through decreasing ROS generating, providing better energe supply for reperfused myocardium.  相似文献   

7.
Roughly speaking, lowlands and hilly areas west of the Kanto district belong tcthe warm-temperate zone. Climax communities in thcse areas arc represented byevergreen oak forests consisting mainly of Castanopsis, Quercus (Subg. Cyclobalano.psis) etc. Such forests extend further westward through the southern tip of Koreaand the southern half of China to the mountain sides of the Himalayas. In thehighlands of Southeast Asia and New Guinea, We can see similar evergreen oakforests, although mixed with many tropical and subtropica1 plants. More thantwenty years ago, Hongo had an opportunity of collccting higher fungi in oakforests (CastanOPsis, Lithocarpus, etc. ) in the interior of Papua New Guinea about1700m above the sea, and met with many familiar fungi that often occur also inevergreen forests of Japan. It was a great surprise that Laccaria vinaceoavellanea,Cortinarias nigrosquamosus and TyloPilus neofelleus, the Japanese species describedby Hongo, wero found there.  相似文献   

8.
Competitive mycelial growth(CMG)between Pleurotus eryngii isolates is genetically controlled,and stable CMG responses(positive,neutral or negative)were recorded among the strains tested.Correlations between CMG responses and mycelial growth rate were observed.CMG simultaneously reflects information relating to somatic incompatibility and mycelia growth rate in edible mushrooms,and can be readily and reliably applied to studies on genetic polymorphism among this group of fungi.  相似文献   

9.
【Obiective】Risk assessment of dietary exposure to pesticide residues in kiwifruit and quantifiction of the dietary risk levels of commonly used pesticides provide references for safe production and guidance for consumption of the fruit, food safety supervision, and revision of the Maximum Residue Limits (MRLs) of kiwifruit.【Methods】Based on detection of the residues of 66 pesticides in 61 kiwifruit samples from a major producing area, chronic dietary intake risk (%ADI) and acute dietary intake risk (%ARfD) of pesticide residues in these samples were assessed. Based on the veterinary drug residue risk ranking matrix constructed by the British Veterinary Drug Residues Committee, the risk of th epesticides and samples was ranked by integrating kiwifruit consumption and pesticide toxicity, frequency of use and residue level, and maximum residue limit estimates (eMRL) were calculated using allowable daily intake (ADI) values, large portion consumed (LP), and body weight (bw). The study will provide a reference for the regulation of the maximum residue limit (MRL) for the corresponding pesticides.【Results】(1)Among the 62 pesticides, a total of 21 pesticides were detected, and they were low-toxic pesticides except for chlorpyrifos, deltamethrin, cypermethrin and cyhalothrin, which were moderately toxic; (2) Using the pesticide toxicology data, acceptable daily intake (ADI) and acute reference does (ARfD), residual data and kiwifruit consumption data, the risk assessment of the 21 pestcides detected showed that the chronic dietary intake (%ADI) of each pesticide inkiwifruitranged from 0.000 01% to 0.016 04%. All the 21 pesticides detected but acetamiprid and chlorpyrifos without ARfD information had an acute dietary intake (%ARfD) ranging from 0.01% to 26.20%. The acute dietary intake risk difference between different pesticides was significantly. (3) According to the residual risk score, the 21 pesticides detected were medium- to low-risk pesticides. The risk scores for deltamethrin and chlorpyrifos were 16.5 and 16.1 ie(15≤S<20), respectively, which were in the medium-risk range. The risk scores of cypermethrin, pyrimidine, buprofezin, cyhalothrin and difenoconazole were between 12.1 and 12.4, and the risk scores of 14 pesticides including procymidone and chlorpyrifos ranged from 8.0 to 9.3 (S< 15). All of them were low-risk pesticides. Among the 61 kiwifruit samples, 45.9% of the samples were in a very low risk area with a pesticide residue risk index (RI) below 5; 34.4% of the samples were in a low risk range with a pesticide residue RI between 5 and 10; and 18.0% of the samples were in a medium risk range with a pesticide residue RI of 10 and 15; (4) At present, there were few standard pesticides in kiwifruit. Among the 21 pesticides detected, only carbendazim, acetamiprid, chlorpyrifos, deltamethrin, and cyhalothrin had maximum residue limit (MRL) in kiwifruit or berries and other small fruits in GB 2763—2016, while 76.2% the pesticides had not a limit value. Compared with eMRL, the MRL values of the five pesticides was a more strict parameter related to limitation of quantities. For example, the eMRL of carbendazim was 6.6 times that of MRL; the eMRL of acetamiprid was 3.8 times that of MRL; the eMRL of cyhalothrin was 10.9 times that of MRL; the eMRL of deltamethrin 21.9 times that of MRL; and the eMRL of chlorfenuron was 153 times that of MRL. Among the 21 pesticides detected, carbendazim, acetamiprid, cyhalothrin, deltamethrin and chlorpyrifos had MRLs, and azoxystrobin, chlorfenapyr, malathion, and procymidone had no necessecity to formulate MRL. 12 pesticides including thiamethoxam, imidacloprid, thiophanate- methyl, tebuconazole, propiconazole, prochloraz, difenoconazole, buprofezin, trifloxystrobin, chlorpyrifos, cypermethrin and chlorothalonil had no MRLs.【Conclusion】The pesticides detected were all middle- risk or low- risk pesticides, and the acute and chronic dietary risks of the 21 pesticides were acceptable. At the same time, 98.4% of the 61 samples were at medium, low or very low risk. Therefore, the kiwifruit in the major producing area was relatively safe. It was recommended to develope the MRLs of 12 pesticides including thiamethoxam and imidacloprid for in kiwifruit. © 2019 Journal of Fruit Science  相似文献   

10.
AIM: To investigate the effects of a 10-weeks treatment with angiotensin Ⅱ (Ang Ⅱ) subtype I receptor antagonist losartan on vascular remodeling of thoracic aorta in male spontaneously hypertensive rats (SHR). METHODS: SHR were treated from 16 to 26 weeks of age with losartan at 15 mg/kg·d-1 or 0.75 mg/kg·d-1. RESULTS: Losartan (15 mg/kg·d-1) treatment significantly decreased systolic blood pressure compared with the control group, while losartan (0.75 mg/kg·d-1) had no the effect, losartan(15 mg) prevents the development of aortic hypertrophy by preventing hypertrophy of vascular smooth muscle cells (VSMC). In the losartan 0.75 group, these parameters were not changed. But in the losartan 15 and losartan 0.75 groups, the collagen content of the aortic media decreased significantly. CONCLUSION: It is inferred that the effect of Ang Ⅱ on stimulating VSMC growth of the aorta in SHR is dependent on arterial pressure, while the effect on collagen fibers is through pressure independent mechanism.  相似文献   

11.
A series of hybrid Flammulina velutipes dikaryons were obtained by crossing yellow and white monokaryons.The color of fruit bodies generated from these dikaryons,and the ratio between dark-colored stipe regions and the entire stipe of individual fruit bodies,were determined.Our data suggest that the expression of fruit body color in the hybrid dikaryons was under the control of factors present in both the white and yellow parent monokaryons,and that multiple alleles exist in both white and yellow color-controlling factors.  相似文献   

12.
Xu  Yanjie  Si  Yali  Yin  Shenglai  Zhang  Wenyuan  Grishchenko  Mikhail  Prins  Herbert H. T.  Gong  Peng  de Boer  Willem F. 《Landscape Ecology》2019,34(2):243-257
Landscape Ecology - Migratory species’ resilience to landscape changes depends on spatial patterns of habitat degradation in relation to their migratory movements, such as the distance...  相似文献   

13.
AIM: To observe the role of zipper-interacting protein kinase (ZIPK) in the regulatory effects of protein kinase Cα (PKCα) and protein kinase Cε (PKCε) on calcium sensitivity during hemorrhagic shock(HS) in rats. METHODS: The skinned first class arborization of superior mesenteric artery (SMA) from HS rats were adopted to observe the influence of inhibitor of ZIPK on the effects of PKCα and PKCε agonists on calcium sensitivity after shock via measuring the contraction initiated by Ca2+ with isolated organ perfusion system, hypoxic vascualr smooth muscle cells (VSMCs) were adopted to measure the protein expression and activity of ZIPK after applying PKCα and PKCε agonists following hypoxia via Western blotting. RESULTS: (1) The calcium sensitivity of SMA was decreased after 2 h shock, and increased by agonists of PKCα and PKCε. Emax of Ca2+ was increased from 47.2%to 66.5% (P<0.01) and 66.3% (P<0.01) of normal control respectively as compared with 2 h shock group. The increasing effects of PKCα and PKCε agonists on calcium sensitivity of SMA after 2 h shock were weakened by the inhibitor of ZIPK. The cumulative dose-response curve of Ca2+ was shifted to the right, the Emax of Ca2+ was decreased to 42.6% and 47.5% of normal control (P<0.01), respectively. (2) The protein expression and activity of ZIPK in VSMCs were decreased after 2 h hypoxia, and were increased by the agonists of PKCα and PKCε following 2 h hypoxia. CONCLUSION: PKCα and PKCε regulate the calcium sensitization probably through changing the protein expression and activity of ZIPK following HS in rats.  相似文献   

14.
The expansion of the Shanghai metropolitan region has caused a substantial amount of farmland to become urbanized. Most farmers have lost their land and have been relocated from villages to new collective settlements, resulting in dramatic changes in the landscape pattern. This study explores the effects of this transformation on the spatiotemporal dynamics of plant diversity. We randomly sampled 22 plots comprising 294 subplots within two crossed transects that pass through 5 traditional villages and 17 new settlements. The results show that resettlement has exerted significant effects on plant species diversity, both temporally and spatially. Temporally, the Gleason index (GI) of total species over time could be ordered as 1990s > 2000s > 1980s, while Shannon’s diversity index (SHDI) was ordered as 2000s > 1990s > 1980s. Spatially, the GI of total species decreased from the urban center to the exurbs or from the inside to the outside of the built-up areas. SHDI was highest in suburbs or ecotones. Furthermore, the GI of total species had significant correlations with those of indigenous species, exotic species, and planted species (r > 0.90, p < 0.01) as well as with the region and location of settlement (r < −0.48, p < 0.01). Both indigenous and exotic species had significant positive correlations with total species richness at 0.01 levels. Generally, compared with traditional settlements, new settlements displayed greater richness and diversity of plant species, primarily because of the exotic species present in new settlements. The farmers’ socio-economic status was found to be the primary cause of differences in species richness. To protect indigenous and wild species, it is necessary to take into account local knowledge in villages to encourage Chinese farmers to participate actively in community greening. A bridge should be built between traditional villages and modern settlements and between the past and future for farmers.  相似文献   

15.
Increasing fertiliser use in agricultural landscapes is likely to threaten the viability of remnant native vegetation in many parts of the world. Australia’s prime grain production landscapes have nutrient poor soils, which formerly supported semi-arid woodland. The ecological function and capacity for regeneration of these remnants may be particularly susceptible to nutrient enrichment. The key sources of nutrients are wind and water deposition from crop fertilisation, and manure and feed from sheep. We hypothesised that these sources would result in unequal deposition of nutrients within and among remnant vegetation patches. We surveyed soil nutrients (Total N, Available P and K, C:N ratio, and soil pH) in the edges and interiors of 60 remnant woodland patches of various sizes, and in adjacent cultivated paddocks. Nutrient load was negatively correlated with remnant size and patterns were particularly strong for available P. Small remnant patches (<3 ha) were accumulation zones for nutrients, with levels comparable or higher than within crop lands. The patterns are consistent with the hypothesis that small remnants are strongly enriched as a result of being used for livestock shelter. In larger remnants, the primary cause of enrichment is consistent with edge accumulation of nutrients due to wind and water movement. In large patches, remnant edges, particularly the windward edge, were elevated compared to interiors of large patches. In these semi-arid crop lands, current trends in intensification of cropping and a shift away from livestock may reduce the input of nutrients to small patches but increase the nutrient threat to larger remnants.  相似文献   

16.
The effect of temperature on germination and days taken for germination was evaluated in Carica papaya cvs., ‘Pune selection-3’ and ‘Pusa Dwarf’. The highest average seed germination per cent was observed in the month of July (96.8 and 93.0?%), followed by August (94 and 88.5?%), whereas the lowest average seed germination was observed in the month of January (44.2 and 36.8?%) in ‘Pune selection-3’ and ‘Pusa Dwarf’, respectively. Minimum number of days (5.17 and 6.33) was observed for germination in the month of July, whereas the maximum number of days (29.5 and 31) was taken in the month of January in both the cultivars, respectively. The average highest germination and seedling height was observed at temperature 29.8 °C and 29.5 °C during July and August, respectively, whereas the lowest was observed at temperature 14 °C and 15.9 °C during January and December, respectively. The optimum time for nursery sowing was July to August for autumn season crop under subtropical conditions of India.  相似文献   

17.
AIM:To study the change of Toll-like reporter 4 (TLR4) expression in Sombatis cell-based model of epilepsy and to explore the role of TLR4 in this model. METHODS:After cultured in vitro for 9 d, the neurons of newborn SD rats were randomly divided into control group and model group. The neurons in model group were cultured in low-magnesium medium for 3 h and then returned to the normal medium culture. The expression of TLR4 at mRNA and protein levels was detected by fluorescence quantitative PCR and the method of immunohistochemistry, respectively. RESULTS:The immunohistochemical results showed that the protein expression of TLR4 was enhanced in the Sombati’s cells. The results of fluorescence quantitative PCR showed that the mRNA expression of TLR4 time-dependently increased in the Sombatis cells (P<0.05). CONCLUSION:The expression of TLR4 in the neurons is up-regulated in Sombatis cell-based model of epilepsy in rats, suggesting that TLR4 is associated with the pathogenesis of epilepsy.  相似文献   

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19.
AIM: To observe the effects of insulin-like growth factorⅡ (IGF-Ⅱ) at different expression levels on hepatocellular carcinoma Huh7 cell proliferation and migration, and to explore the role of IGF-Ⅱ in the development of HCC. METHODS: The Huh7 cells were transfected with the over-expression plasmid pcDNA3.1(+)- IGF-Ⅱ or RNA interference plasmid pLVX-shRNA-IGF-Ⅱ by Lipofectamine 2000. The quantitative real-time PCR and Western blotting were used to verify the expression of IGF-II. The biological behaviors of the Huh7 cells were analyzed by CCK-8 assay, plate clone formation assay, cell scratch test and Transwell chamber experiment.RESULTS: Over-expression of IGF-II promoted the growth and migration of hepatocellular carcinoma cells (P < 0.05), and the cell proliferation was significantly inhibited in the Huh7 cells with low IGF-II expression (P < 0.05).CONCLUSION: IGF-II is involved in the regulation of biological behavior of hepatocellular carcinoma Huh7 cells in vitro, which may play a promoting role in the development of hepatocellular carcinoma.  相似文献   

20.
There are sporadic reports on urban forests in Indian cities. Nagpur is one of the greenest cities of India with 18 per cent of its area under forests and plantations, 17 per cent under cultivation and 2 per cent under water bodies. The present study showed that natural vegetation of the city is very well diversified with a representation of 59 per cent vegetation including 124 trees species belonging to 38 families as compared with the overall district vegetation statistics. Air quality in the city is relatively better with lower SO2 (6 μg/m3), NO2 (18 μg/m3) and Respirable Suspended Particulate Matters (RSPM, 53 μg/m3) as against National Ambient Air Quality Standards (2009) for cities in India of 80, 80 and 100 μg/m3, respectively. It was also noted that the diversity in natural forests which are being protected is greater than the plantations undertaken by the civic authorities and private sector efforts. The study thus demonstrated the positive relationship of the city with diversified vegetation cover for cleaner environment. The analysis is expected to guide formulation of strategies for maintaining green space in the city.  相似文献   

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