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981.
Mohammad Shaheed Hossain Chowdhury DaneshMiah 《林业研究》2003,14(3):253-258
An exploratory study was conducted on the housing pattern and food habit of the Mro tribe in Bandarban region,Bangladesh, highlighting their indigenous knowledge. The study was carried out with respect to three income groups. A total of 36 households (12 from each income groups) were assessed using different participatory appraisals through semi-structured questionnaires. A special type of indigenous knowledge on housing pattern and food habit was explored in the Mro community, which correspond to the severe dependence on forest resources. 相似文献
982.
An efficient and improved shoot regeneration technique for the micropropagation of Vitex negundo, an aromatic and medicinal shrub through in vitro culture of nodal segments with axillary buds, is described. Thidiazuron
(TDZ) used at 1.0 μM was the most effective in inducing bud break and growth, and also in initiating multiple shoot proliferation
at the rate of 25 microshoots per nodal explant with axillary buds, after 4 weeks of culture. By repeated subculturing of
nodal explants, a high-frequency multiplication rate was established. Optimum shoot multiplication and elongation was achieved
when TDZ exposed explants were subcultured on Murashige and Skoog (MS) media containing a combination of 1.0 μM 6-benzyladenine
(BA) and 0.5 μM α-naphthalene acetic acid (NAA). Efficient rooting was achieved directly in soilrite when basal portion of
the shoots were treated with 500 μM indole-3-butyric acid for 10 min which was the most effective in inducing roots, as 97%
of the microshoots produced roots. Plantlets went through a hardening phase in a controlled plant growth chamber, prior to
ex-vitro transfer. Micropropagated plants grew well, attained maturity and flowered. No phenotypical differences for morphogenesis
were observed among the regenerants. 相似文献
983.
通过半探问的方式,采用不同的参与评估法对36户么偌人分3组进行了评估。么偌部落严重依赖森林资源,在房屋格局和饮食习性方面形成了特殊的本土文化。图2表2参31。 相似文献
984.
Mohammad Samaun Safa 《Small-Scale Forestry》2004,3(2):223-238
The sal forest is the only plainland forest in Bangladesh, and is of national economic and environmental importance. High
population and ever increasing poverty has stimulated exploitation of the forest alarmingly and brought it near extinction.
In facing this situation, the Bangladesh Forest Department implemented a participatory management approach, involving the
householders living in and around the forests, for forest maintenance and protection. This study examines the effectiveness
of practicing participatory forestry on the settlers’ livelihood in the encorached area of the sal forest. The settlers were
given degraded and encroached forest land through the program. Two major social forestry models — namely agroforestry and
woodlots — are included in the study. Participation in the resettlement increased household income, employment opportunities
and financial and non-land assets. It was found that the participatory management regime could attain the sustainability of
the forest and accelerate the standard of settlers’ livelihood, hence the program is an efficient management option towards
sustainability of the forest resources. These findings suggest that there is a role for extending the approach to rehabilitate
other degraded and encroached forest lands in Bangladesh. 相似文献
985.
Rahman MM Lopa SS Sadik G Harun-Or-Rashid Islam R Khondkar P Alam AH Rashid MA 《Fitoterapia》2005,76(7-8):758-761
O-Methylmoschatoline, liriodenine and 3,4-dihydroxybenzoic acid isolated from the barks of Cananga odorata showed antibacterial activities against a number of Gram (+) and Gram (-) bacteria. The compounds also showed antifungal and cytotoxic activities. 相似文献
986.
Mohammad Moghaddam Bahman Ehdaie J. Giles Waines 《Genetic Resources and Crop Evolution》2000,47(3):323-334
Genetic variation and its distribution within and among 23 populations of Triticum urartu collected from Syria, Lebanon, Turkey, Armenia, and Iran was estimated using isozyme markers at eight polymorphic loci. The number of alleles per locus (A= 1.21), percentage polymorphic loci (P= 20.1%), and mean gene diversity (He= 0.024) were relatively low. In a population from Lebanon, a high number of alleles per locus (A= 2.13) and percentage polymorphic loci (P= 87.5%) was found. On average, genetic variation among populations (GST= 0.407) was smaller than within-population variation (0.593). However, different patterns of genetic structure were found among various geographic regions. Interpopulation variation was highest for the Iranian populations (0.89) followed by the Turkish populations (0.66). A reverse pattern was observed for the Syrian (0.11) and for the Lebanese (0.13) populations. The Armenian populations exhibited similar interpopulation and within-population variation. Principal component and cluster analyses resulted in distinct grouping of the geographically proximal populations, with the exception of the two Iranian populations. The Turkish populations were different from the neighboring Armenian populations compared to other countries. The populations from southern Syria and those from Lebanon also exhibited a high degree of genetic diversity. The two most heterozygous loci, Mdh-2 and Pgi-2, separated the populations along the first and second principal components, respectively. Most of the rare alleles were scattered sporadically throughout the geographic regions. Rare alleles with high frequencies were found in the Turkish and Armenian populations. These results indicated that different geographic regions require specific sampling procedures in order to capture the range of genetic variation observed in T. urartu populations. 相似文献
987.
Ryegrass (Lolium perenne L.) in grassland is known to sustain with water and nitrogen (N). This study investigates biomass and N partitioning in plant organs (roots, main and the youngest tillers) under water-nitrogen interactions. Nitrogen was applied at the rates of 50 and 100 mg N kg?1 as N1 (low N) and N2 (high N) treatments, respectively, with uniform irrigation until 440 growing degree-days (GDD). Thereafter, the water supply was restricted to 50 mL on a weekly basis (W1) against 50 mL on a daily basis (W2) and concurrently, N enriched with 1 atom% 15N isotopes. Cumulative tillers’ biomass increased linearly from 1st to 8th order, but thereafter reached a plateau with further increases in number of negligible weights. Initially tiller mass and number per plan did not differ (P < 0.05) with water and/or N applications but changed at 788 GDD with clear differences at 911 GDD with the highest under N2W2 and lowest under N1W1. Nitrogen concentration sharply decreased from 530 to 700 GDD and then levelled off with age. The decline was more pronounced in tillers than roots. The high N treatment showed elevated N-concentration under both water treatments. Watering on a daily basis promoted vegetative growth. High water and N levels significantly (P < 0.05) influenced concentration of N absorbed during 15N labeling (NL) in all organs with relatively pronounced NL under N2. The additive positive effect of W2 and N2 was obvious on NL as compared to NT, which showed that plants discriminate N-uptake on mass basis. Nitrogen (mobile) was higher in young and 15N (heavier) was low in young tillers and vice versa. Accumulation of N absorbed during 15N labeling (15NA) was significant knowing that water is a strong determining factor of N concentration in ryegrass organs. 相似文献
988.
Masoud Selk Ghaffari Mohammad Ali Rezaei Amir Hessam Mirani Nargess Khorami 《Veterinary ophthalmology》2010,13(2):91-93
Objective To determine the effects of intravenous ketamine‐midazolam anesthesia on intraocular pressure (IOP) in ocular normotensive dogs. Animals Thirteen adult mixed‐breed dogs. Procedures Dogs were randomly assigned to treatment (n = 7) and control (n = 6) groups. Dogs in the treatment group received intravenous ketamine 15 mg/kg and midazolam 0.2 mg/kg and dogs in the control group received intravenous saline. The time of intravenous drug injection was recorded (T0). Measurements of IOP were then repeated 5 min (T5) and 20 min (T20) following the intravenous administration of ketamine‐midazolam combination and saline in both groups. Results Measurements showed normal IOP values in both groups. The mean ± SD baseline IOP values for treatment and control groups were 13.00 ± 1.47 and 10.33 ± 2.20, respectively. For baseline IOP values, there was no significant difference between treatment and control groups (P = 0.162). In the treatment group, the subsequent post‐treatment mean ± SD values were 15.64 ± 2.17 (5 min), and 14.92 ± 1.98 (20 min). There was no evidence of statistical difference between baseline values and post‐treatment values after treatment with ketamine‐midazolam (P5 = 0.139; P20 = 0.442). In control eyes, the mean ± SD values at 5 and 20 min were 10.41 ± 2.01 and 10.16 ± 1.69, respectively. There was no significant difference between baseline values and post‐treatment values in control group (P5 = 1.000; P20 = 1.000). Conclusion Ketamine‐midazolam combination has no clinically significant effect on IOP in the dog. 相似文献
989.
In the present study the antigenotoxic effect of apigenin was studied against a genotoxic dose of ethinylestradiol using the damage parameters of chromosomal aberrations (CAs), sister chromatid exchanges (SCEs) and cell cycle kinetics (CCK). Human peripheral blood lymphocytes were cultured and treated with 10 μM of ethinylestradiol along with doses of 5, 10, 15 and 20 μM of apigenin. A clear decrease in the genotoxic damage induced by ethinylestradiol was observed with increasing doses of apigenin, suggesting a protective role for apigenin during ethinylestradiol therapy. 相似文献
990.
在过去的几十年里,遥感与地理信息系统融合技术应用于土壤侵蚀评价的研究得到了显著的发展。本研究采用遥感资料、土壤和土地调查数据、数字地面模型和气象观测数据,利用地理信息系统技术来分别产生通用土壤流失方程(USLE)的各个参数,从而来评价水土流失量和空间分布状况。 相似文献