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161.
Multi-criteria evaluation approach to GIS-based land-suitability classification for tilapia farming in Bangladesh 总被引:1,自引:0,他引:1
M. Shahadat Hossain Sayedur Rahman Chowdhury Nani Gopal Das M. Moshiur Rahaman 《Aquaculture International》2007,15(6):425-443
Site selection is a key factor in any aquaculture operation, because it affects both success and sustainability. It can, moreover,
solve conflicts between different activities, making rational use of the land. This study was conducted to identify suitable
sites for development of Nile tilapia (Oreochromis niloticus) farming in Sitakunda Upazila (sub-district), Bangladesh, using GIS-based multi-criteria evaluation of water and soil quality,
topography, infrastructure and socio-economic factors. ASTER image and eighteen thematic layers were analyzed using ENVI and
ArcView software to identify the suitable areas for tilapia farm development. A constraint layer was used to exclude areas
from suitability maps that cannot be allowed to implement tilapia farming. A series of GIS models were developed to identify
and prioritize the most suitable areas for tilapia farming. The output of the model clearly indicates the location and extent
of tilapia farming areas on different suitability scales, i.e. most suitable (7,744 ha), moderately suitable (2,479 ha), and
not suitable (838 ha). Model outputs were assessed against field verification data, and were consistent. Because existing
aquaculture covers only 1,540 ha of land in the study area, the potential for expanding tilapia farms should take into consideration
socio-political and environmental issues. The results are encouraging in terms of tilapia culture development and suggest
that grassland–agriculture areas could be used for sustainable development of tilapia farming to diversify the economic activities
of rural communities. 相似文献
162.
Schad GA Chowdhury AB Dean CG Kochar VK Nawalinski TA Thomas J Tonascia JA 《Science (New York, N.Y.)》1973,180(4085):502-504
Contrary to general belief, larvae of Ancylostoma duodenale do not always develop directly to adulthood upon invasion of man. In West Bengal, India, arrested development appears to be a seasonal phenomenon which results in (i) reduction of egg output wasted in seeding an inhospitable environment and (ii) a marked increase in eggs entering the environment just before the monsoon begins. 相似文献
163.
Anther culture of recalcitrant indica × Basmati rice hybrids 总被引:1,自引:1,他引:0
U. Bishnoi R.K. Jain J.S. Rohilla V.K. Chowdhury K.R. Gupta J.B. Chowdhury 《Euphytica》2000,114(2):93-101
Fertile, green, di-haploid plants were obtained at high frequencies from several indica × Basmati rice F1 hybrids and/or F2 plant populations using an improved anther culture procedure. Anthers from cold-pretreated (10 °C for 10 d) panicles of six indica (HKR120, HKR86-3, HKR86-217, PR106, Gobind andCH2 double dwarf) and two Basmati rice (Basmati
370,Taraori Basmati) varieties and 14 heterotic indica ×Basmati F1/F2 hybrids were cultured in modified agarose-solidified N6M, Heh5M and RZM media. Best callus induction frequencies (2.6–78%)
were obtained in RZM medium containing 4% (w/v) maltose,2,4-D, NAA and kinetin. F2 plants compared to F1 hybrids and parental rice varieties, were more responsive to anther culture. Androgenesis frequencies of 31–78% were obtained
for indica × Basmati F2 plants in RZM medium in just 30 d which are comparable to or higher than that reported for japonica rice varieties and hybrids
involving japonica rice parent(s). Agarose (1.0% w/v)-solidified MS medium containing 3.0% maltose, kinetin, BAP, and NAA,
induced green shoot regeneration in 0–51% of the anther-derived callide pending upon the genotype. High plant regeneration
frequencies (67–337 green plants per 1000 anthers)were obtained from anther calli of several F1hybrids (Gobind × Basmati 370 and HKR120 ×Taraori Basmati) and F2 plants (Gobind × Basmati370, Gobind × Taraori Basmati, HKR86-3 × TaraoriBasmati). A sample of 498 plants obtained from the
above hybrids, were transferred to pots with>90% survival; 8–78% of these plants had >5%spikelet fertility and were diploid.
In addition,18% of the haploid plants could be diploidized by submerging in 0.1% colchicine solution for 16–18 h. The improved
anther culture procedure reported here, resulted in several fold increase in the recovery of green plants from recalcitrant
indica × Basmati rice hybrids compared to previous published procedures. The study may accelerate the introgression of desirable
genes from indica into Basmati rice using anther culture as a breeding tool.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
164.
Genetic diversity was investigated in 348 accessions and subaccessions of grasspea (Lathyrus sativus L.) from 10 geographical regions. Polymorphism for 20 isozymes of 13 enzyme systems was studied to estimate the genetic diversity. The Near East and North Africa regions included the most variability for these isozyme systems, suggesting that the center of diversity (center of origin) for grasspea is in this general area. The lowest variability was found in accessions and subaccessions from South America, followed by those from Sudan–Ethiopia. Diversity was measured for individual loci over regions and EST-1 and SKDH had the highest genetic diversity. The closest genetic diversity was observed for LAP-2, followed by AAT-1 and PGM. The closest genetic distance existed between populations from the Near East and North Africa. Populations from South Asia and Sudan–Ethiopia, though geographically widely separated, exhibited a closer genetic distance from each other than from other regions. 相似文献
165.
The effects of a dietary protease‐complex on performance,digestive and immune enzyme activity,and disease resistance of Litopenaeus vannamei fed high plant protein diets 下载免费PDF全文
Hong‐Li Song Bei‐Ping Tan Shu‐Yan Chi Yao Liu M A Kabir Chowdhury Xiao‐Hui Dong 《Aquaculture Research》2017,48(5):2550-2560
The effects of a dietary protease‐complex on growth performance, body composition, digestive and immune enzyme activity of Litopenaeus vannamei and its resistance to a pathogenic Vibrio parahaemolyticus were assessed in a 9‐week trial. A high fish meal diet (HF) containing 200 g kg?1 fish meal and a low fish meal diet (LF) containing 100 g kg?1 fish meal were designed as a positive and negative control respectively. Three other diets (LF+125P, LF+150P, and LF+175P) were manufactured by supplementing graded level of a protease‐complex (125, 150 and 175 mg kg?1, respectively) to the LF diet. All diets were formulated to be iso‐proteic and iso‐energetic. Most performance indices of shrimp fed the LF+175P diets were similar to the HF diet. Among the digestive enzymes, trypsin, lipase and amylase activity in hepatopancreas of shrimp fed LF+175P diets (4576 U mg?1 protein and 16, 32 U g?1 protein, respectively) were higher than those fed the LF diets but lower than the HF diets (P < 0.05). Total superoxide dismutase and polyphenol oxidase contents in both serum and hepatopancreas were higher and serum malondialdehyde content and the cumulative mortality during disease challenge tests were lower for the diets containing the protease‐complex than those fed the LF diets (P < 0.05) with no difference with those fed the HF diets. 相似文献
166.
Md. Arif Chowdhury Yahya Khairun Md. Salequzzaman Md. Mizanur Rahman 《Aquaculture International》2011,19(6):1193-1206
This study analyzed water and soil quality and environmental impacts of shrimp farming in the southwestern coastal region
of Bangladesh. Shrimp farming in the region is very traditional in nature where two culture systems viz. shrimp–rice and shrimp-only
are being practiced, which are characterized by lower production, repeated stocking, irregular feeding, and fertilizing. Water
quality in both farming systems was found suitable for optimum growth and survival of shrimp (Penaeus spp.). The level of 5-day biological oxygen demand (BOD5) in both systems even in canal water was within the recommended level provided by the Government of Bangladesh which is less
than 5 mg/l. Therefore, effluents of shrimp farms in the study area did not show any nutrient pollution on the surrounding
environment. However, saltwater intrusion has caused many problems like loss of agricultural production, reduced availability
of fodder for livestock, and fresh water for domestic uses in the coastal region. The findings of this study confirmed that
shrimp farming using saline water have long-term effect of soil salinization. As a result, it poses a real threat toward sustainability
of coastal shrimp farming as well as coastal development in Bangladesh. 相似文献
167.
Shaima Chowdhury Sharna Tek Maraseni Ando Mariot Radanielson 《Soil Use and Management》2023,39(4):1267-1288
Sustainable Soil Management Practices (SSMP) offer potential benefits while conserving natural resources. However, the low adoption of SSMP limits the achievement of their full potential. To examine the current state of knowledge on SSMP adoption and identify research gaps, we systematically reviewed 269 peer-reviewed publications pooled from Scopus, Web of Science and ScienceDirect, covering the period from 1994 to 2022. We assessed the temporal and spatial transitions of SSMP adoption and identified a broad perspective of 14 themes on SSMP adoption and highlight the research trends and gaps. Prior to 2010, research on SSMP adoption was concentrated on a few themes and has become diversified in later years, covering emerging themes such as climate change and use Information and Communication Technology (ICT). Publications on SSMP adoption exhibited a global distribution, with particular emphasis on the African continent due to the flow of donors' funds driven by severe soil degradation and limited use of improved technologies in Africa. Studies on minimum soil disturbance were prevalent worldwide, with the highest number of publications. Our findings also indicate a strong research collaboration between developed and developing countries, showcasing donor-driven collaborative efforts and mutual benefits across different regions. This review however highlights the limited inclusion of local knowledge in SSMP promotion and recommends a bottom-up approach for future initiatives. In the discussion section, different critical factors of SSMP adoption covering farmers' perceptions, climate change, policy impact and the use of ICT are discussed. These findings and identified research gaps are useful for further research and the development of sustainable soil management policies, programmes and projects. 相似文献