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81.
Chingakham Premabati Devi Anilabha D. Munshi Tusar Kanti Behera Harshwardhan Choudhary Partha Saha 《The Journal of Horticultural Science and Biotechnology》2016,91(1):87-92
Immature fruit of cultivated species of eggplant (Solanum melongena L.) are commonly used as a summer vegetable in India. Rich morphological variation exists among the cultivated species of eggplant in different growing regions of the country. We have characterised 24 breeding lines of Solanum spp., including 20 eggplant cultivars and four wild species of eggplant, based on 13 morphological characters using Mahalonabis D2 statistics. All 24 breeding lines of Solanum spp., including the 20 eggplant cultivars and four wild species, were grouped into four clusters by agglomerative clustering. Cluster II and Cluster IV contained the most accessions (eight each), while Cluster I and Cluster III had four accessions each. The highest inter-cluster (D2) distance (158.33) was observed between Cluster I and Cluster II, followed by Cluster I and Cluster III (108.48), and Cluster II and Cluster IV (102.96), which indicated that accessions in Cluster I and Cluster II were more divergent than those in the other clusters. The highest intra-cluster distance (5.80) was observed in Cluster IV, with eight genotypes, and the lowest intra-cluster distance (2.21) was observed in Cluster II, also with eight genotypes. The intra-cluster distances in all four clusters were lower than the inter-cluster distances, which indicated that genotypes within the same cluster were closely related. Genotypes in Cluster IV had the maximum number of flowers per cluster (3.63), the highest number of fruit per cluster (3.25), and number of fruit per plant (208.63), which revealed that genotypes could be selected from Cluster IV for these characters. The first three principal components (PC1, PC2, and PC3) accounted 73.99% of the total variation among the 24 genotypes. These phenotypic data increase the feasibility of prioritising breeding lines in a crossing programme based on the uniqueness of their desirable morphological traits. 相似文献
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Cheslav Balash Bruce Colbourne Neil Bose Wayne Raman-Nair 《Aquacultural Engineering》2009,41(1):14-21
The hydrodynamic loads on plane net samples of differing mesh geometry are measured in steady and oscillating flows. The steady loads on plane nets are also numerically simulated. The net is modeled as an inter-connected system of lumped masses and springs. The loads are computed for each twine segment and applied to the lumped masses at the segment ends. The equations of motion are formulated for the coupled dynamics of the masses and solved numerically. Drag data from the experiments is compared with analytical and numerical models and existing empirical formulae. Results for steady flows indicate that drag coefficients for nets and cylinders, as a function of the Reynolds number, have identical trends with consistent offsets. It is concluded that the drag coefficient for nets is equivalent to the drag coefficient for cylinders (and spheres for knotted nets) modified by a function of net solidity. For unsteady flows, the drag and added mass are extracted from the total wave force by applying a vector approach. It is shown that drag and added mass coefficients are not well quantified by conventional non-dimensional parameters (i.e. Keulegan–Carpenter and Reynolds numbers). The unsteady drag coefficient is presented as a function of wave particle velocity, wave period and net porosity. It is proposed that the added mass coefficient be expressed by an assumption of an effective thickness—conceptually the width of water affected by the net, which is a function of wave frequency and net solidity. 相似文献
84.
The significance of Cryptosporidium as a causative agent of diarrhea has been assessed in bovine for a period of 2 years. A total of 940 faecal samples (470 samples in each year) both from diarrhoeic and non-diarrhoeic bovine (0-12 months age) were examined during three different seasons (rainy season, summer and winter). Overall Cryptosporidium was detected in 17.46% and 18.04% cases in first and second year, respectively. Out of 50.21% diarrhoeic and 49.79% non-diarrhoeic cases Cryptosporidium was detected in 26.79% and 8.13% in first year and 27.49% and 8.59% in second year. Year did not have any significant effect on the occurrence of cryptosporidiosis in bovine during this study period. The prevalence of cryptosporidiosis, both in diarrhoeic (61.64%) and non-diarrhoeic (47.22%) cases was highest in 0-1-month age group (P<0.01). Such a high percentage of cryptosporidiosis in clinically asymptomatic animals indicated that the particular age group of animals might be reservoir for the parasite. During this study period highest prevalence was recorded in rainy season (27.55%) followed by summer (16.99%) and winter (8.71%) (P<0.01). A total of 166 positive cases were genotyped. Molecular characterization of bovine cryptosporidiosis has been carried out by PCR-RFLP analysis of SSU rRNA gene and results indicated that Cryptosporidium parvum mainly responsible for diarrhea in bovine in India. 相似文献
85.
Ujjwal Kanti Paul Gurudas Das Avishek Ray Tanuj Mathur 《International Journal of Fruit Science》2017,17(3):269-279
This study intends to fill the gaps in the organic agriculture literature emerging from infrequent use of farm budget-related data, overlooking the imputed costs and non-existence of long-run return and profitability estimates. The results suggest that the organic system is economically unviable as the growers fail to recover their total production cost. However, growers’ returns exceed their ‘perceived’ production cost, which excludes their imputed expenses. Temporal, spatial, and size-based analysis also attests to this. On the contrary, cultivation in two sample villages where the household’s size, its head’s age, percentage of land, and yield are significantly higher, remain economically viable. 相似文献
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88.
Sang S Ju J Lambert JD Lin Y Hong J Bose M Wang S Bai N He K Reddy BS Ho CT Li F Yang CS 《Journal of agricultural and food chemistry》2006,54(26):9792-9797
This study was designed to investigate the cancer preventive activities of wheat bran (WB) oil. We studied the colon cancer preventive effects of WB oil and its subfractions in the Apc(min/+) mouse model, a recognized mouse model for human colorectal cancer, and used human colon cancer cell lines (HCT-116 and HT-29) to identify possible active fractions in WB oil. Our results showed that the oil fraction of WB was more active than the water fraction against the growth of human colon cancer cell lines and that 2% WB oil significantly inhibited the overall tumorigenesis by 35.7% (p < 0.0001) in the Apc(min/+) mouse model. The WB oil was further fractioned into nonpolar lipids and phytochemicals and the phytochemical fraction was fractionated into phytosterols and phytosterol ferulates, 5-alk(en)ylresorcinols, and unidentified constituents by normal phase silica gel column chromatography. Results on cell culture showed that the phytochemical fraction had a higher inhibitory effect on HCT-116 human colon cancer cells than that of WB oil, whereas the nonpolar lipid fraction had less growth inhibitory effectiveness. However, neither fractions showed a stronger inhibition than WB oil in the Apc(min/+) mouse model. The current results demonstrate, for the first time, the intestinal cancer preventive activity of WB oil. The active ingredients, however, remain to be identified. 相似文献
89.
Johnson Kayode Adesodun Mutiau O. Atayese T. A. Agbaje Bose A. Osadiaye O. F. Mafe Adeniyi A. Soretire 《Water, air, and soil pollution》2010,207(1-4):195-201
Two species of sunflower, i.e., Tithonia diversifolia and Helianthus annuus, were investigated for their potential to remove heavy metals from contaminated soils. Dried and mature T. diversifolia (Mexican flower) seeds were collected along roadsides, while H. annuus (sunflower) seeds were sourced from the Department of PBST, University of Agriculture Abeokuta, Nigeria. The contaminants were added as lead nitrate (Pb (NO3)2) and zinc nitrate (Zn (NO3)2) at 400 mg/kg which represents upper critical soil concentration for both Pb and Zn. The results indicated that T. diversifolia mopped up substantial concentrations of Pb in the above-ground biomass compared to concentrations in the roots. The concentrations in the leaf compartment were 87.3, 71.3, and 71.5 mg/kg at 4, 6, and 8 weeks after planting (AP), respectively. In roots, it was 99.4 mg/kg, 97.4 mg/g, and 77.7 mg/kg while 79.3, 77.8, and 60.7 mg/kg were observed in the stems at 4, 6, and 8 weeks AP, respectively. Observations with H. annuus followed the pattern found with T. diversifolia, showing significant (p?<?0.05) accumulation of Pb in the above-ground biomass. Results obtained from Zn contaminated soils showed significant (p?<?0.05) accumulation in the above-ground compartments of T. diversifolia and H. annuus compared with root. However, the highest accumulation of Zn was observed in the leaf. The translocation factor and enrichment coefficient of Pb and Zn with these plant species are greater than 1, indicating that these metals moved more easily in these plants. However, this result also showed that the translocation of Zn from root to the shoot of the two plants was higher than Pb. In conclusion, this experiment showed that these plants accumulated substantial Pb and Zn in their shoots (leaf and stem) at 4 weeks AP which diminished with time. This implies that the efficiency of these plants in cleaning the contaminated soils was at the early stage of their growth. 相似文献
90.