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1.
Abstract

The antioxidant effects of ellagic acid (EA) and hesperidin (HES) against skeletal muscle ischemia/reperfusion injury (I/R) were performed. Hindlimb ischemia has been induced by tourniquet occlusion for 2?h on left hindlimb. At the end of ischemia, the tourniquate has been removed and initiated reperfusion for 2?h. EA (100?mg/kg) has been applied orally before ischemia/reperfusion in the EA?+?I/R group. HES (100?mg/kg) has been given orally in the HES?+?I/R group. The left gastrocnemius muscle has been harvested and stored immediately at??80?°C until assessed for the levels of MDA and antioxidant enzymes activities. MDA level has statistically increased in I/R group (p?<?0.05) compared to other groups. The muscle tissue antioxidant enzymes activities were lower than the other groups in the I/R group (p?<?0.05). EA and HES treatments significantly reversed the damage level in I/R, also activity of tissue SOD increased in the EA?+?I/R and HES?+?I/R groups.  相似文献   
2.
The expected changes in the frequency of alleles affecting the sex ratio   总被引:3,自引:0,他引:3  
An equation is derived giving the changes per generation in the frequency of alleles affecting the sex ratio. The alleles considered are assumed to be those of an autosomal locus and to act only in one sex. The results indicate that alleles determining the production of more males should always be more common in males than in females.  相似文献   
3.
Uzi Nur 《Chromosoma》1961,12(1):272-279
Summary Unequal bivalents were found in two of four populations of the short horned grasshopper, Calliptamus palaestinensis bdhr. sampled in Israel.The inequality of the homologues was due to an extra segment which was heterochromatic and apparently terminal. Pairing configurations at pachytene and position of chiasmata at later stages revealed however that the extra segment was interstitial, and the long member terminated in a minute segment homologous to the terminal part of its normal partner. The percentage of reductional divisions at anaphase I corresponded well with the percentage of terminal chiasmata (i.e. distal to the extra segment) observed at diakinesis.The assumption of an interstitial position of the extra segment would explain the previously puzzling examples of unequal bivalents in Orthoptera whose reductional divisions have not been readily accounted for otherwise.  相似文献   
4.
To determine how the cost of reproduction varies with brood size, a population of blue tits (Parus caeruleus) breeding in Wytham Wood, England, was manipulated over a three year period. Two hundred sixteen pairs were randomly assigned 3, 6, 9, 12, or 15 nestlings; nestlings were exchanged soon after hatching. Survival of adult females (as measured by the proportion recaptured in the following winter and/or spring) declined significantly with increasing brood size in two out of three years; there was significant year-to-year variation in the relationship of recapture rate to brood size. Mean female recapture rates (averaged over the three years) declined in a linear fashion (P < 0.01). There was no significant linear or curvilinear relationship between male-recapture rate and brood size in any of the three years nor was there a significant linear or curvilinear relationship for the data averaged over the three years. Nevertheless, recapture proportions for males differed significantly with respect to brood size (χ2 test, P < 0.05). The possibility that experimental brood size influences subsequent dispersal (and therefore biases measures of survival based on recapture rates to differing degrees) was examined by comparing distances moved by breeding adults from one year to the next. There was no relationship between brood size and dispersal distance within the study area for either sex, except that females given broods of three were significantly more likely to move more than 300 m than were those given broods of 6–15 young. Both males and females showed evidence of a cost with respect to future fecundity: as brood size increased, the number of surviving offspring produced in the following year decreased from 1.5–1.6 (for adults that had reared 3–6 young) to 0.4 (for those that had reared 15 young). The relationship of future reproductive success to experimental brood size did not differ among years or between the sexes. The number of eggs laid and number of young hatched in year n + 1 did not differ significantly with respect to brood size in year n; rather, differences in future fecundity reflected differences in the survival prospects of young reared in year n + 1.  相似文献   
5.
Azospirillum brasilense was attracted to capillaries containing either phosphate buffer, distilled water, or saline. The number of bacteria in these capillaries was 3–4×104, after 1 h of incubation. In the presence of phosphate buffer + attractants, the number of cells accumulated in the capillary increased only to 5×104–1.1×105 cells. It was not possible, therefore, to measure chemotaxis inA. brasilense as distinct from aerotaxis by the capillary method. Chemotaxis was observed in semi-solid agar plates and was determined by a growth band oriented towards the attractant. Positive chemotactic response was obtained with peptone, tryptone, yeast extract, amino acids, organic acids, arabinose and galactose.  相似文献   
6.
Spore suspensions from 7 day old cultures of Curvularia lunata (Wakker) Boedijn var. aeria (Batista, Lima and Vasconcelos) M.B. Ellis were added to soil samples originally devoid of Curvularia propagules. The test fungus disappeared after six weeks of inoculation irrespective of soil amendments, like the application of green manure, urea, superphosphate, or soil cropped to Sorghum (dura) or cotton seedlings.  相似文献   
7.
8.

Petroleum pollution is a major concern in Antarctica due to the persistent nature of its hydrocarbon components coupled with the region’s extreme environmental conditions, which means that bioremediation approaches are largely inapplicable at present. The current study assessed the ability of the psychrotolerant phenol-degrader, Rhodococcus sp. strain AQ5-07, to assimilate diesel fuel as the sole carbon source. Factors expected to influence the efficiency of diesel degradation, including the initial hydrocarbon concentration, nitrogen source concentration and type, temperature, pH and salinity were studied. Strain AQ5-07 displayed optimal cell growth and biodegradation activity at 1% v/v initial diesel concentration, 1 g/L NH4Cl concentration, pH 7 and 1% NaCl during one-factor-at-a-time (OFAT) analyses. Strain AQ5-07 was psychrotolerant based on its optimum growth temperature being near 20 °C. In conventionally optimised media, strain AQ5-07 showed total petroleum hydrocarbons (TPH) mineralisation of 75.83%. However, the optimised condition for TPH mineralisation predicted through statistical response surface methodology (RSM) enhanced the reduction to 90.39% within a 2 days incubation. Our preliminary data support strain AQ5-07 being a potential candidate for real-field soil bioremediation by specifically adopting sludge-phase bioreactor system in chronically cold environments such as Antarctica. The study also confirmed the utility of RSM in medium optimisation.

  相似文献   
9.
Genus Rusa, belonging to the deer family Cervidae is native to the Indo-Malaya Archipelago (IMA). However, detailed information on the Rusa genus in the IMA is limited. This review provides comprehensive information on the Rusa genus in the IMA including, threats and conservation efforts. There are four species of deer in Rusa genus, which is Sambar deer (Rusa unicolor), Javan deer (Rusa timorensis), Visayan spotted deer (Rusa alfredi) and Philippine deer (Rusa marianna). Despite their wide distribution in the South Asian and Southeast Asian regions, they are under serious threats. Some conservation efforts that are being done to protect and conserve them among others are; (1) facilities protection, (2) habitat enrichment programme, (3) Ex-situ conservation, (4) legislations, and (5) captive breeding. Conservation through genetics is also an important step in conserving these species. Recommendations for conservation of the genus are also discussed; 1. maintenance of ecosystem. 2. more effective monitoring system on the existing protected area. 3. ex-situ conservation, and 4. habitat monitoring.  相似文献   
10.

Aims

The aim of this study was to characterize Streptococcus agalactiae strains that were isolated from fishes in Malaysia using random amplified polymorphic DNA (RAPD) and repetitive extragenic palindromic PCR (REP‐PCR) techniques.

Methods and Results

A total of 181 strains of Strep. agalactiae isolated from red hybrid tilapia (Oreochromis sp.) and golden pompano (Trachinotus blochii) were characterized using RAPD and REP‐PCR techniques. Both the fingerprinting techniques generated reproducible band patterns, differing in the number and molecular mass amplicons. The RAPD technique displayed greater discriminatory power by its production of more complex binding pattern and divided all the strains into 13 groups, compared to 9 by REP‐PCR technique. Both techniques showed the availability to differentiate the genetic profiles of the strains according to their geographical location of origin. Three strains of Strep. agalactiae that were recovered from golden pompano showed a genetic dissimilarity from the strains isolated from red hybrid tilapia, while the strain of ATCC 27956 that recovered from bovine displayed a unique profile for both methods.

Conclusions

Both techniques possess excellent discriminative capabilities and can be used as a rapid means of comparing Strep. agalactiae strains for future epidemiological investigation.

Significance and Impact of the Study

Framework as the guideline in traceability of this disease and in the search for potential local vaccine candidates for streptococcosis in this country.  相似文献   
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