排序方式: 共有51条查询结果,搜索用时 15 毫秒
1.
Heat shock protein 70 expression in different tissues of Cirrhinus mrigala (Ham.) following heat stress 总被引:2,自引:0,他引:2
Members of heat shock protein 70 (HSP70) are highly conserved proteins of about 70 kDa and play important roles in protein folding. Levels of these proteins increase when cells are under stress. Environmental temperature influences both the basal and induced levels of HSPs. However, studies on HSPs in fishes from a tropical country such as India are lacking. In the present study, Indian major carp (IMC) Cirrhinus mrigala (Ham.) acclimatized at 25±2°C had high levels of HSP70, viz., 1.2–1.3 ng μg?1 total protein in kidney and gill and 4.2–5.3 ng μg?1 total protein in liver and brain tissues, indicating the presence of biochemically significant levels of stress. However, maintenance of acclimatized fish at 17°C for up to 48 h did not lead to a significant decrease in stress protein levels. A heat shock at 37°C for up to 48 h resulted in only two to threefold increase in HSP70 levels in these organs. Although the increase in HSP70 levels was apparent from the first hour of heat stress in all these tissues, the increase was significant from the second hour in the brain, the sixth hour in liver and kidney and the 20th hour in the gills. 相似文献
2.
The forests of Austrocedrus chilensis in southern Argentina suffer mortality from “mal del ciprés”, whose causes remain unknown. The purpose of this work was to establish the relation of soil features with the occurrence of the disease. In Río Grande Valley, Chubut Province, Argentina, 14 areas with “mal del ciprés” were selected for study. The spatial pattern of the decline varied among the different areas and was classified as aggregated and disaggregated. In each area, symptomatic and asymptomatic plots were established and characterized by 11 edaphic and topographic variables. Three forest areas where the disease was totally absent were also included. Site features were related to the occurrence of the decline using principal component analysis and cluster analysis. Results indicated that soil properties related to poor internal drainage, such as the proximity to water streams, non-allophanized soils of fine textures, and redoximorphic features, act as predisposing factors to the development of “mal del ciprés”. Poor soil drainage was strongly associated not only with the occurrence of the disease, but also with its spatial pattern. Symptomatic and asymptomatic plots presented similar edaphic features in areas with a disaggregated distribution of the decline and were grouped together in the multivariate analysis. This result suggests that large areas with such a pattern are prone to develop the decline. 相似文献
3.
Dry deciduous forests of the eastern lateritic part of India are a typical case where forest valuation is yet to be integrated with the non-timber forest products like wild edible mushrooms (WEMs), which have a wide use in subsistence and cash income. A detailed accounting of the production and utilization of WEMs harvested from that region was made to highlight the economic worth of WEMs to the Santal community of this region. The WEMs production in the forest was in a polynomial pattern during the monsoon period. The net present value of revenues from WEMs was estimated to be contributing 9.83 and 10.29 % of total annual income of a Santal family of the Choupahari and Gonpur forests, respectively. The ecological footprint of the Santal communities on WEMs was higher in the forest area which was closer to the local markets than did the distant ones. Forest areas of the eastern lateritic part of India have a strong potentiality to produce WEMs that may be helpful for socio-economic upliftment of local tribal communities through the development of entrepreneurship and policy making. 相似文献
4.
M. C. Manna M. Singh S. Kundu A. K. Tripathi P. N. Takkar 《Biology and Fertility of Soils》1997,24(1):129-132
An outdoor study was undertaken using polyethylene containers to assess the suitability of different organic residues, soybean straw (Glycine max L. Merril.), wheat straw (Triticum aestivum L.), maize stover (Zea mays L.), chickpea straw (citer arietinum L.) and city garbage, as food for the tropical epigeic earthwormPerionyx excavatus, and to assess the influence of this earthworm on the decomposition of these materials. Maize stover was found to be the most suitable of the food materials used. Population growth ofP. excavatus was enhanced by addition of these organic materials in the temperature range 24°-30°C, while the population was adversely affected above 30°C in a vermiculture system. Addition of earthworms accelerated the breakdown of residues, which ultimately resulted in a lowering of the C:N ratio, water-soluble carbon and carbohydrates, and increased ash percentage and cation exchange capacity compared with their respective controls. 相似文献
5.
Colloidal quantum rods of cadmium selenide (CdSe) exhibit linearly polarized emission. Empirical pseudopotential calculations predict that slightly elongated CdSe nanocrystals have polarized emission along the long axis, unlike spherical dots, which emit plane-polarized light. Single-molecule luminescence spectroscopy measurements on CdSe quantum rods with an aspect ratio between 1 and 30 confirm a sharp transition from nonpolarized to purely linearly polarized emission at an aspect ratio of 2. Linearly polarized luminescent chromophores are highly desirable in a variety of applications. 相似文献
6.
Austrocedrus chilensis is an endemic conifer of Patagonia that suffers a widespread mortality whose causes are a topic of discussion. Since Phytophthora austrocedrae is the most probable cause, we proposed that the spatial and temporal patterns of disease at small scale should reflect pathogen behavior. We aimed at characterizing the spatial and temporal patterns of diseased trees in different soil types and the effect of microsite variability on diseased trees spatial pattern. The spatial pattern of disease was influenced by soil type and tree density. In clay soils with low disease incidence (ca. 25%), the spatial pattern was random and not influenced by abiotic microsite conditions. When disease incidence increased (ca. 70%), concurring with denser plots, the spatial pattern was clustered, as a result of an infection process, and it was independent of microsite variability. In soils with better drainage conditions, that is, alluvial soils with volcanic ash input and coarse textured volcanic soils, the disease was clustered and associated with flat microtopographies. The progression of the disease at small scale was influenced by soil, precipitation and tree density. The spatial and temporal patterns of disease progression were associated with a contagion process and with environmental variables that affect drainage, coinciding with Phytophthora biology and requirements. Our results concur in pointing at Phytophthora as the cause of A. chilensis disease in the study area. Management practices should be urgently applied in order to minimize the spread of the inoculum. 相似文献
7.
Austrocedrus chilensis forests suffer from a disease caused by Phytophthora austrocedrae, which is found often in wet soils. We applied three widely used modelling techniques, with different data requirements,
to model disease potential distribution under current environmental conditions: Mahalanobis distance, Maxent and Logistic
regression. Each model was built using field data of health condition and landscape layers of environmental conditions (distance
to streams, slope, aspect, elevation, mean annual precipitation and soil pH NaF). We compared model predictions by area under
the receiver operating characteristic curve and Kappa statistics. A reasonable ability to predict observed disease distribution
was found for each of the three modelling techniques. However, Maxent and Logistic regression presented the best predictive
performance, with significant differences with respect to the Mahalanobis distance model. Our results suggested that if good
absence data are available, Logistic regression should be used in order to better discriminate sites with high risk of disease.
On the other hand, if absence data are not available or doubtful, Maxent could be a very good option. The three models predicted
that around 50% (49–56%) of the currently asymptomatic forests are located on sites at risk of disease according to abiotic
factors. Most of these asymptomatic forests surround the current diseased patches, at distances lower than 100 m from diseased
patches. Management considerations and the scope of future studies were discussed in this article. 相似文献
8.
First detection of canine parvovirus type 2c in pups with haemorrhagic enteritis in Spain 总被引:7,自引:0,他引:7
Decaro N Martella V Desario C Bellacicco AL Camero M Manna L d'Aloja D Buonavoglia C 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2006,53(10):468-472
Canine parvovirus type 2 (CPV-2), the aetiological agent of haemorrhagic enteritis in dogs, includes three antigenic variants, types 2a, 2b and 2c. CPV-2c has been detected initially in Italy and subsequently in Vietnam. We report the first identification of this novel antigenic variant in Spain, where it caused an outbreak of fatal enteritis in basset hound pups in association with canine coronavirus type I and type II. We suggest that this new antigenic variant of CPV-2 could spread throughout Europe and that there is a subsequent need to update current CPV vaccines. 相似文献
9.
Clinical and Laboratory Findings in Equine Piroplasmosis 总被引:1,自引:0,他引:1
Rosanna Zobba Mauro Ardu Serena Niccolini Bernardo Chessa Laura Manna Raffaella Cocco Maria Luisa Pinna Parpaglia 《Journal of Equine Veterinary Science》2008,28(5):301-308
The objective of this study was to evaluate equine piroplasmosis (EP) as a cause of morbidity in horses in Sardinia (Italy), describe the clinical signs and altered hematologic and biochemical parameters, and illustrate response to different treatments. Among 44 horses suspected of tick-borne disease, 38 were polymerase chain reaction (PCR) positive for Theileria equi (n = 27) or Babesia caballi (n = 6), whereas five were positive for both protozoans. Typical clinical features of piroplasmosis were seen in some of the horses, whereas others had nonspecific mild symptoms. Hematologic findings revealed involvement of the three blood cell lineages (anemia, leukopenia or leukocytosis, thrombocytopenia), and biochemical variations were related to increased bilirubin, alteration of serum phosphorus, and hypoalbuminemia. We suggest that the two protozoans are the most important causative agents of equine tick-borne disease in this geographic area, and we observe that different clinical features are associated with the disease; in addition to the typical aspects of piroplasmosis, characterized by fever, pale mucous membranes, and icterus, we can signal other nonspecific mild signs such as weight loss, weight loss associated with an insignificant leukopenia, or weight loss associated with depression, anorexia, and mild hyperbilirubin. The study is intended as a practical contribution for veterinary practitioners because it describes different clinical presentations and laboratory findings of EP, suggests diagnostic and therapeutic approaches to the disease, and shows diffusion of the disease in a Mediterranean region. 相似文献
10.