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71.
1. The present study was conducted to estimate genetic relatedness among Nicobari fowls (Brown, Black and White) and an exotic bird (White Leghorn) using random amplified polymorphic DNA (RAPD) polymorphism. 2. A total of 25 decamer primers were screened among all the breeds of which 24 primers amplified the genomic DNA, generating 2000 to 200 bp bands. Ten primers generated reproducible and distinct RAPD profiles and were used for further analysis. 3. A total of 94 bands were amplified and 30 polymorphic bands (32%) were produced. The number of polymorphic loci ranged from 1 to 5 with an average of 3.0. 4. Among the native breeds Brown Nicobari showed higher genetic similarity (0.85) than Black Nicobari (0.80) and White Nicobari fowl (0.82). 5. Brown Nicobari showed high genetic similarity with Black Nicobari (0.87 +/- 0.029); least similarity was between White Nicobari and White Leghorn (0.77 +/- 0.028). 6. The RAPD profile of all Nicobari fowls on amplification with the primers PBG5 and PBA12 showed specific bands of molecular size 1050 and 785 bp, respectively. 7. The native breeds showed the least genetic distance with each other while White Leghorn appeared to be most distant from the native breeds.  相似文献   
72.
Understanding biodiversity and community composition is a prerequisite to sustainable exploitation and conservation of fisheries. We assessed the spatial and seasonal patterns of fish community composition and biodiversity in seasonal no-take riverine sanctuaries in Bangladesh, which aim to conserve the anadromous hilsa shad (Tenualosa spp. and Hilsa keele). Fish samples were collected during monsoon, as well as pre- and postmonsoon, from five sites within two sanctuaries and one site in an open fishing area. Although total abundance was similar along the rivers, species richness was significantly higher at the open fishing site due to its connectivity to nearby habitats. The diversity apparently decreased in a downstream direction. Fish communities at two upstream sites were separated from other sites in multivariate space largely due to higher abundance of hilsa at downstream sites and presence of floodplain-oriented species at the two upstream sites. Short body length and high trophic level at all sites indicated that fish communities were overexploited. Our results also indicated that riverine hilsa sanctuaries in Bangladesh are rich in fish species diversity and support several threatened species designated by the International Union for Conservation of Nature (IUCN). Our study also suggested that since hilsa abundance shapes community patterns, it can therefore impact riverine ecosystem functioning in the sanctuary areas. The findings of this study can serve as an important baseline for future biodiversity assessment, conservation and impact assessment of conservation in rivers, and therefore help to establish multispecies ecosystem-based management of riverine fisheries around the world.  相似文献   
73.
In jute (Corchorus olitorius), quantitative trait loci (QTL) analysis was conducted to study the genetics of eight fibre yield traits and two fibre quality traits. For this purpose, we used a mapping population consisting of 120 recombinant inbred lines (RILs) and also used a linkage map consisting of 36 SSR markers that was developed by us earlier (Das et al. 2011). The RIL population was derived from the cross JRO 524 (coarse fibre) × PPO4 (fine fibre) following single seed descent. Using single-locus analysis involving composite interval mapping, a total of 21 QTLs were identified for eight fibre yield traits whereas for fibre quality (fibre fineness), only one QTL was detected. The QTL for fibre fineness explained 8.31–10.56% of the phenotypic variation and was detected in two out of three environments. Using two-locus analysis involving QTLNetwork, as many as 11 M-QTLs were identified for seven fibre yield traits (excluding top diameter) and one M-QTL was identified for fibre fineness which accounted for 4.57% of the phenotypic variation. For six fibre yield traits, we detected 16 E-QTLs involved in nine QQ epistatic interactions. For fibre fineness, four E-QTLs involved in two QQ epistatic interactions and for fibre strength, six E-QTLs involved in three QQ epistatic interactions were identified. Eight out of the 11 M-QTLs observed for the fibre yield traits were also involved in QE interactions; for fibre fineness and fibre strength, no QE interactions were observed.  相似文献   
74.
Serum electrolytes, minerals, blood biochemical and plasma enzymes were studied in heat exposed buffalo heifers supplemented with yeast powder in feed to alleviate the adverse effects of heat stress. Eighteen healthy Murrah buffalo heifers (270-280) kg were divided into three groups. Animals of group I were kept in shed and served as control, while group II and group III were exposed in a psychrometric chamber at 40°C for 4?hrs daily for 16?days continuously. The animals in group III were also supplemented with yeast powder at 10?g per animal per day. The serum sodium, potassium and chloride levels decreased significantly (P?相似文献   
75.
The effects of conceptual land cover change scenarios on the generation of storm runoffs were evaluated in the Nyando Basin. The spatial scenarios represented alternatives that vary between full deforestation and reforestation. Synthetic storm events of depths 40, 60 and 80 mm were formulated according to the rainfall patterns and assumed to have durations corresponding to the runoff times of concentration. The Natural Resource Conservation Service–Curve Number model was used to generate runoff volumes within the sub‐catchments, which were subsequently routed downstream to obtain effects in the whole basin. The simulated land cover change impacts were evaluated relative to values obtained from the actual land cover state of the basin in the year 2000. From the results, an agricultural land cover scenario constituting of about 86 per cent of agriculture indicated increased runoff volumes in the entire basin by about 12 per cent. An agricultural‐forested land cover scenario with 40 and 51 per cent of forest and agriculture respectively revealed reduced runoff volumes by about 12 per cent. Alternatively, a scenario depicting a largely forested land cover state with about 78 per cent of forests reduced the runoff volumes by about 25 per cent according to the model estimates. Runoff volumes in the basin were also likely to reduce by about 15 per cent if the appropriate land cover scenario for the respective sub‐catchments were to be assumed for runoff management purposes. Considering the prevalent data uncertainty, the study effectively highlights the potential hydrological vulnerability of the basin. The results obtained can form a basis for appropriate catchment management of the area. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
76.
Toxicokinetic behavior and metabolism studies of metamitron and its effect on the cytochrome P(450) content of liver microsomal pellet were carried out in black Bengal goats after a single oral administration at 278 mg kg(-1) and consecutive oral administration of 30 mg kg(-1) for 7 days. Metamitron was detected in the blood sample at 0.08 h (12.0 +/- 0.87 microg mL(-1)), maximum at 4 h (84.3 +/- 8.60 microg mL(-1)) and minimum (14.6 +/- 1.67 microg mL(-1)) at 36 h blood sample after a single oral administration. The absorption rate constant was 0.69 +/- 0.09 h(-1). The Vd(area) (2.00 +/- 0.08 L kg(-1)) and t(1/2)beta (8.98 +/- 0.70 h) values suggested wide distribution and long persistence of the compound in the body. The values of T approximately B (0.80 +/- 0.04), F(c) (0.55 +/- 0.01), Cl(B) (0.15 +/- 0.00 L kg(-1) h(-1)), and K(21) (0.41 +/- 0.03 h(-1)) suggested that metamitron retained in the blood compared to that in the tissue. Maximum concentration of metamitron residue was found in the adrenal gland followed by bile on day 4 of single oral administration. The higher Cl(R) compared to Cl(H) value indicated the excretion of the major portion (34-40%) through urine compared to feces (20-26%). Maximum concentrations of metamitron and its metabolite, deaminometamitron, were excreted through urine and feces at 48 and 24 h samples, respectively. The recovery of metamitron including its metabolite in terms of parent compound varied from 69.3 to 80.1%, of which contribution of metabolite in terms of parent compound varied from 53.1 to 63.0%. Repeated oral administration of metamitron at 30 mg kg(-1) for 7 days caused induction of the cytochrome P(450) content of liver microsomal pellet of goat, suggesting oxidative deamination of metamitron.  相似文献   
77.
A search was made for 26Mg (26Mg*) from the decay of 26Al (half-life = 0.73 million years) in Al-rich objects from unequilibrated ordinary chondrites. Two Ca-Al-rich inclusions (CAIs) and two Al-rich chondrules (not CAIs) were found that contained 26Al when they formed. Internal isochrons for the CAIs yielded an initial 26Al/27Al ratio [(26Al/27Al)0] of 5 x 10(-5), indistinguishable from most CAIs in carbonaceous chondrites. This result shows that CAIs with this level of 26Al are present throughout the classes of chondrites and strengthens the notion that 26Al was widespread in the early solar system. The two Al-rich chondrules have lower 26Mg*, corresponding to a (26Al/27Al)0 ratio of approximately 9 x 10(-6). Five other Al-rich chondrules contain no resolvable 26Mg*. If chondrules and CAIs formed from an isotopically homogeneous reservoir, then the chondrules with 26Al must have formed or been last altered approximately2 million years after CAIs formed; the 26Mg*-free chondrules formed >1 to 3 million years later still. Because 26Mg*-containing and 26Mg*-free chondrules are both found in Chainpur, which was not heated to more than approximately400°C, it follows that parent body metamorphism cannot explain the absence of 26Mg* in some of these chondrules. Rather, its absence indicates that the lifetime of the solar nebula over which CAIs and chondrules formed extended over approximately5 million years.  相似文献   
78.
Supplementation of exogenous growth hormone (GH) during prepuberty advances onset of spermatogenesis in boars, but the mechanism of action is unknown. The present study is an investigation of the presence and characteristics of testicular growth hormone receptors (GHR). A total of 36 boars were castrated, three boars every 10 days, between the ages of 10 and 120 days. Testicular membrane preparations of 10, 20, 30, 50, 70, 100 and 120‐day‐old boars were used to determine 125I‐bGH binding and Scatchard analysis. Liver from a 60‐kg barrow was used for comparison. Specific 125I‐bGH binding to testicular membrane preparations occurred in all age groups with the exception of 20‐day‐old boars at levels of 30–40% of liver binding. At 30 days of age the unlabelled bGH at 1.1 ng/tube achieved half maximal inhibition (ID50). Results of Scatchard analysis indicated a single class of binding sites. Binding affinity was 2.89 × 109m with a binding capacity of 12 fmole/mg membrane protein. The results from this study suggest that GH may act directly on the cells of the prepubertal boar testis.  相似文献   
79.
Anti-inflammatory activity of (+)-usnic acid.   总被引:5,自引:0,他引:5  
(+)-Usnic acid, isolated from the lichen Roccella montagnei, showed a dose-dependent anti-inflammatory activity when tested on rats, employing acute and chronic models.  相似文献   
80.
A. SÜSS  B. GRAMPP 《Weed Research》1973,13(3):254-266
Zusammenfassung. Um den Einfluß verschiedener Bodenmischungen auf die Aufnahme von adsorbiertem [14C]-markíertem Monolinuron zu verfolgen, wurden jeweils 30, 45, 60, 73 und 90 g Monolinuron-behandelter Boden (0,42-0,53 μg Monolinuron/g Boden) mit unbehandeltem auf 100 g aufgefüllt und damit 15.4–67.1 μg adsorbiertes Monolinuron eingesetzt. Die Aufnahme durch Senipflanzen wurde in Neubauerversuchen während 24 Tagen verfolgt. In 3 Anbauperioden wurden 1.17–9.74 μg aufgenommen. Der überwiegende Teil blieb jedoch an den Boden adsorbiert. Bei einer Bilanzerstellung konnten 99% der zu Versuchsbeginn eingesetzten Monolinuronmenge wieder gefunden werden, Durch den Sorptionsprozeß wurde Monolinuron chemisch nicht vcerändert. Ebenso kann das Ausgangsmolekül in der Pflanze nachgewiesen werden. Die nachweisbare Monolinuronmenge in der Pflanzensubstariz wird umso geringer, je weiter die Aufnahmeintensität zurürkgeht. Über eine Isotopen-Austauschreaktion wurde versucht, das pflanzenverfügbare Monolinuron zu messen.
The uptake of adsorbed monolinuron in the soil by mustard plants  相似文献   
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