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排序方式: 共有697条查询结果,搜索用时 62 毫秒
31.
Muthusamy Ranjithkumar Buddhi Chandrasekaran Saravanan Suresh Chandra Yadav Rajender Kumar Rajendra Singh Sahadeb Dey 《Tropical animal health and production》2014,46(2):371-377
Trypanosoma evansi infection typically produces wasting disease, but it can also develop into a neurological or meningoencephalitis form in equids. Trypanosomiasis in horses was treated with quinapyramine sulfate, and all the 14 infected animals were recovered clinically. After clinical recovery, four animals developed a neurological form of the disease at various intervals. Two of these animals treated with diminazene aceturate recovered temporarily. Repeated attempts failed to find the parasite in the blood or the cerebrospinal fluid (CSF), but all of the animals were positive in enzyme-linked immunosorbent assay. The calculation of the antibody index (AI) in the serum and the CSF and polymerase chain reaction (PCR) analysis of the CSF and brain tissue were carried out to confirm the neuro-infection. We found PCR and AI analyses of the CSF to be useful tools in the diagnosis of the neurological form of trypanosomiasis when the organism cannot be found in the blood or CSF. The increased albumin quotient is indicative of barrier leakage due to neuroinflammation. The biochemical changes in the CSF due to nervous system trypanosomiasis include increases in the albumin quotient, total protein, and urea nitrogen. It seems to be the first report on relapse of the nervous form of trypanosomiasis in equids even after quinapyramine treatment in endemic areas. 相似文献
32.
H. M. Tuihedur Rahman Jiban Chandra Deb Gordon M. Hickey Imrul Kayes 《Journal of Forest Research》2014,19(1):12-21
This research contrasts the financial profitability of different agroforestry practices in community-based buffer zone management of Madhupur National Park (MNP), Bangladesh. This park is the second largest in Bangladesh and subjected to enormous anthropogenic pressure and land rights-related conflicts. This paper reports the different agroforestry practices of villagers in different modules of the buffer zone of MNP, identified by a participatory research approach. It then assesses the profitability of each module on the basis of cost–benefit analysis, net present value, internal rate of return, and annualized income. Results indicate three agroforestry systems were being practised in the buffer zone by the participants: agro-silviculture, agro-silvo-horticulture, and combined woodlot and agroforestry. Among these modules, agro-silvo-horticulture was the most profitable, followed by agro-silviculture then combined woodlot and agroforestry. We recognize that not all of the participants can practise intensive agroforestry; our results suggest that the community-based buffer zone management strategy for MNP would benefit from prioritizing agroforestry practices where possible. This will lead to more successful buffer zone management for the conservation of natural forests while supporting the development of local resource-dependent communities. 相似文献
33.
Effect of sub-lethal nitrite on selected haematological parameters in fingerling Catla catla (Hamilton) 总被引:1,自引:0,他引:1
Pratap Chandra Das Subanna Ayyappan Joy Krushna Jena & Basanta Kumar Das 《Aquaculture Research》2004,35(9):874-880
A sub‐lethal nitrite toxicity trial was conducted using static conditions for a period of 96 h with fingerlings of Catla catla (21.4±3.6 g). Fingerlings were exposed to five concentrations of nitrite, that is, 1, 2, 4, 8 and 10.4 mg L?1 and a nitrite‐free control to study changes in haematological parameters. Nitrite caused an increase in immature erythrocyte population (7–24%) in lower concentrations (0–4 mg L?1) at 6 h while they were absent in higher concentrations. The total erythrocyte count was reduced at 6 h followed by an increase at 12 h with further reduction up to 96 h in all concentrations of nitrite. The 96‐h exposure resulted in 21.2–31.8% reduction in erythrocyte population in 1–10.4 mg L?1 nitrite. The haemoglobin content decreased progressively with increasing nitrite concentrations as well as exposure periods. Total leukocyte count decreased initially at 6 h in all treatments followed by an increase after 12 h, signifying development of a protective response of the body to nitrite stress. Blood glucose decreased initially up to 24 h followed by an increase through 96 h. Serum protein level decreased continuously with increasing exposure period. The study revealed that exposure to nitrite caused changes in almost all the haematological parameters in the fingerlings depending on the concentration as well as exposure period. Nitrite being one of the important inorganic nutrients often recorded at higher levels in intensively cultured ponds, the present study highlights its adverse impact on fish and stressed the need for the management of this nutrient in culture ponds. 相似文献
34.
Comparative changes in water quality and role of pond soil after application of different levels of organic and inorganic inputs 总被引:2,自引:0,他引:2
Changes in water parameters were studied in a yard experiment for 7 weeks after application of cow dung at 20, 50 and 100 t ha?1, poultry manure at 4, 10 and 20 t ha?1, feed mixture (groundnut oil cake and rice bran at 1:1) at 10, 20 and 30 t ha?1 and inorganic fertilizers at 100 kg urea+50 kg single super phosphate (SSP) ha?1, twice this dose (2x ha?1) and thrice this dose (3x ha?1). To study the role of soil in the mineralization process, each treatment was divided into two groups – one with and the other without soil substrate. Higher degree of changes in water parameters was observed at higher input levels. Both organic amendment and inorganic fertilization caused significant reduction (P<0.05) in dissolved oxygen and increase in free CO2, dissolved organic matter, total ammonia, nitrite, nitrate and phosphorus contents of water. Organic inputs significantly decreased (P<0.05) water pH and increased total alkalinity and hardness. In contrast, inorganic fertilization caused a significant increase in pH; alkalinity and hardness increased significantly in the presence of soil, but reduced in its absence. In organic input, presence of soil substrate caused significantly lower value of pH, dissolved oxygen, dissolved organic matter and phosphate‐phosphorus and significantly higher free CO2, alkalinity, hardness, ammonia, nitrite and nitrate contents, compared with those in the absence of soil, revealing enhanced microbial mineralization in the presence of soil. 相似文献
35.
Arsenic contamination of shallow groundwater and related health problems are threats for the millions in endemic regions of West Bengal. Contamination of rice grain creates the food chain pathway of mineral arsenic besides drinking water contamination. Present study concentrated on association of arsenic concentration in irrigated water, paddy field soil and rice with the cropping seasons. Irrigated ground water arsenic concentration decreased significantly (p = 0.007) from summer (median 0.42 mg l?1) to winter (median 0.35 mg l?1). Carried over effect created significant decrease (p = 0.03) of paddy field soil arsenic concentration from summer (median 8.35 mg kg?1) to winter (median 6.17 mg kg?1). Seasonal variation was observed in rice straw (p = 0.03) but not in husk (p = 0.91). Arsenic concentration decreased significantly (p = 0.05) in the rice grains collected in winter season (median 0.23 mg kg?1) than the samples collected in the summer season (median 0.30 mg kg?1). In conclusion, seasonal effects need to be considered in case of human health risk assessment from arsenic consumption. 相似文献
36.
Present study is focused on the preparation of two layers composite wound dressing for drug release. The outer layer is made of hydrogel which contains of drug and the core layer is made of fabric. The two layers structure of composite dressing is formed by grafting of polyacrylamide-co-acrylic acid hydrogel on cotton fabric using ammonium per sulphate (APS) as chemical initiator and polyethylene glycol (PEG) as crosslinker. The major factors affecting graft copolymerization of hydrogel on cotton fabric are optimized by varying concentration of monomers & initiator, reaction temperature and addition time of crosslinker. Maximum grafting of hydrogel is obtained at 5 % (w/v) APS and 15 % acrylamide/acrylic acid (1:1 w/w ratio) concentration. The FTIR spectra of composite dressing shows characteristics peak of acrylic acid and acrylamide. The composite wound dressing material is loaded with model drug bovine serum albumin (BSA) and drug release behaviour is studied at different pH. The dressing shows drug release in different pH with maximum release of drug in acidic medium. 相似文献
37.
Sathanandam Pavithra N. Patil Prakash Rekha Ajitha Muthuvel Iyamperumal Patel Amrutlal R. Boggala Ramesh B. Shirol Adiveppa M. Ravishankar Kundapura V. 《Genetic Resources and Crop Evolution》2022,69(8):2787-2801
Genetic Resources and Crop Evolution - Manilkara zapota (L.) P. Royen, a widely adapted and popular tree meant for its appetizing fruits in tropics with no genomic resources like microsatellite... 相似文献
38.
The allelopathic potential of Eucalyptus globulus Labill. (gum tree) fresh and dried leaf leachates was studied using two perennial weeds, viz. purple nutsedge (Cyperus rotundus L.) and bermuda grass (Cynodon dactylon L. Pers) as test weeds. Aqueous leachate of fresh leaves of eucalyptus significantly suppressed the establishment of vegetative propagules and early seedling growth of the weeds. Leachate of fresh leaf cuttings had growth inhibitory effect on bermuda grass but showed growth promotion effect on purple nutsedge. Similarly the leachate of dried leaves of eucalyptus had differential influence on the growth of the two weeds. There is a possibility to harness the allelochemicals of eucalyptus leaves as herbicides for the management of these perennial weeds. 相似文献
39.
S.?Vijayalakshmi Kusum?Yadav Chanda?Kushwaha S.?B.?Sarode C.?P.?Srivastava Ramesh?Chand B.?D.?SinghEmail author 《Euphytica》2005,144(3):265-274
Summary Two RAPD markers linked to gene for resistance (assayed as pustule number cm−2 leaf area) to rust [Uromyces fabae (Pers.) de Bary] in pea (Pisum sativum L.) were identified using a mapping population of 31 BC1F1 [HUVP 1 (HUVP 1 × FC 1] plants, FC 1 being the resistant parent. The analysis of genetics of rust resistance was based on
the parents, F1, F2, BC1F1 and BC1F2 generations. Rust resistance in pea is of non-hypersensitive type; it appeared to be governed by a single partially dominant
gene for which symbol Ruf is proposed. Further, this trait seems to be affected by some polygenes in addition to the proposed oligogene Ruf. A total of 614 decamer primers were used to survey the parental polymorphism with regard to DNA amplification by polymerase
chain reaction. The primers that amplified polymorphic bands present in the resistant parent (FC 1) were used for bulked segregant
analysis. Those markers that amplified consistently and differentially in the resistant and susceptible bulks were separately
tested with the 31 BC1F1 individuals. Two RAPD makers, viz., SC10-82360 (primer, GCCGTGAAGT), and SCRI-711000 (primer, GTGGCGTAGT), flanking the rust resistance gene (Ruf) with a distance of 10.8 cM (0.097 rF and LOD of 5.05) and 24.5 cM (0.194 rF and a LOD of 2.72), respectively, were identified.
These RAPD markers were not close enough to Ruf to allow a dependable maker-assisted selection for rust resistance. However, if the two makers flanking Ruf were used together, the effectiveness of MAS would be improved considerably. 相似文献
40.
Sukumar Saha Mehmet Karaca Johnie N. Jenkins Allan E. Zipf O. Umesh K. Reddy Ramesh V. Kantety 《Euphytica》2003,130(3):355-364
Microsatellites or Simple Sequence Repeats(SSRs) are informative molecular genetic markers in many crop species. SSRs are
PCR-based, highly polymorphic, abundant, widely distributed throughout the genome and inherited in a co-dominant manner in
most cases. Here we describe the presence of SSRs in cDNAs of cotton. Thirty one SSR primer pairs of 220 (∼14%) tested led
to PCR amplification of discrete fragments using cotton leaf cDNA as template. Sequence analysis showed 25% of 24randomly
selected cDNA clones amplified with different SSR primer pairs contained repeat motifs. We further showed that sequences from
the SSR-containing cDNAs were conserved across G. barbadense and G. hirsutum, revealing the importance of the SSR markers for comparative mapping of transcribed genes. Data mining for plant SSR-ESTs
from the publicly available databases identified SSRs motifs in many plant species,including cotton, in a range of 1.1 to4.8%
of the submitted ESTs for a given species.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献