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161.
162.
In the present study, an assessment of land suitability potential for agriculture in the study area of IBB governorate, Republic of Yemen has been conducted through close examination of the indicators of land characteristics and qualities. The objective of this study is to evaluate the available land resource and produce the potential map of the study area. Remote sensing data help in mapping land resources, especially in mountainous areas where accessibility is limited. Satellite imagery data used for this study includes data from multi-temporal Landsat TM which dated June 2001. The parameters taken into consideration were 16 thematic maps i.e., slope, DEM, rainfall, soil, land use, land degradation as well as land characteristics maps. Satellite image of the study area has been classified for land use, land degradation and soil maps preparation, while topo sheet and ancillary data have been used for slope and DEM maps and soil properties determination. The land potential of the study area was categorized as very high, high, moderate, low and very low by adopting the logical criteria. These categories were arrived at by integrating the various layers with corresponding weights in a Geographical Information System (GIS). The study demonstrates that the study area can be categorized into spatially distributed agriculture potential zones based on the soil properties, terrain characteristics and analyzing present land use. This approach has the potential as a useful tool for guiding policy decision on sustainable land resource management.  相似文献   
163.
A 60‐day feeding study was performed to evaluate the role of dietary commercial wood charcoal (CWC) in fish growth performance, body composition and water quality of fingerlings red tilapias (Oreochromis mossambicus × Oreochromis niloticus). Four levels of charcoal (10, 20, 30 and 40 g kg?1) were added to the control diet (0 g kg?1 CWC) and fed to red tilapias (initial weight of 1.20 ± 0.04 g). At the end of the feeding trial, the fish weight gain, specific growth rate, feed conversion ratio, protein efficiency ratio and energy retention of the fish groups fed 30 and 40 g kg?1 (CWC) in diet were significantly (P < 0.05) higher comparing with all other tested fish groups. Moreover, some proximate composition such as crude protein and nitrogen retention efficiency g kg?1 of the fish groups fed on 30 and 40 g kg?1 CWC diets showed higher values (P < 0.05) than those of other tested fish groups (0, 10 and 20 g kg?1 CWC). Apparent digestibility coefficients of protein and dry matter were improved (P < 0.05) in CWC‐tested fish groups compared to the control fish group. These data were powered by the data of the water quality that showed significant (P < 0.05) enhancement in both dissolved oxygen and ammonia concentrations by the increment in dietary charcoal levels. The above‐mentioned parameters' data suggested that 30 g kg?1 dietary CWC can be considered as a suitable level to maintain normal growth of red tilapia juveniles as well as to enhance water quality of the rearing area.  相似文献   
164.
The objective of this study was to investigate the dietary effect of vitamin C in amelioration some of studied alterations induced by fenitrothion in Nile tilapia (Oreochromis niloticus). Nile tilapia was exposed to sub-lethal concentration of fenitrothion 0.04 mg/l (96 h LC50 value was 0.8 mg/l), and basal diet was supplemented with two different dose of vitamin C (500 and 1200 mg/kg B wt/day) for 30 days. Vitamin C supplemented groups showed significant decrease in plasma cortisol and glucose level, enzymes activity of liver and gills (catalase, glutathione-S-transferase and superoxide dismutase) and % of tail DNA damage compared to exposed group. Moreover, fish revealed significant increase in total plasma protein, albumin, globulin and A/G ratio. High dose of vitamin C dietary supplementation (1200 mg/kg B wt/day) returns these parameters to its normal levels with no significant difference compared to non exposed control group. These results indicated that incorporation of high dose of vitamin C (1200 mg) in aqua feed for 30 days could be potentially less expensive and effective in reducing the alterations induced by fenitrothion in Nile tilapia.  相似文献   
165.
Improved rice lines were developed frome three parents with the resistance or tolerance to bacterial leaf blight, blast and drought stress, respectively, using single-, double- and three-way crosses. The improved lines were assessed for agro-morphological and yield traits under non-drought stress (NS) and reproductive-stage drought stress (RS) treatments. The mean comparison of traits measured between parent plants and progenies (improved lines) were similar, and there were significant and non-significant differences among the parents and improved lines (genotypes) under NS and RS. Smilarly, there was significant and non-significant differences in the interaction among both parent varieties and improved lines for NS and RS. Cluster and 3D-model of principal component analysis did not generate categorical clusters according to crossing methods, and there were no exclusive crossing method inclined variations under the treatments. The improved lines were high-yielding, disease resistant, and drought-tolerant compared with their parents. All the crossing methods were good for this crop improvement program without preference to any, despite the number of genes introgressed.  相似文献   
166.
A field experiment was carried out over two years to investigate the effects of an irrigation regime and its interaction with plant density on yield, yield components and water use efficiency (WUE) of safflower Giza 1 cv. The experiment was laid out in randomized complete block design with split plot arrangement with three replications. There were three available soil moisture depletion levels (ASMD) under this study (I1:50% of ASMD, I2:65% of ASMD and I3:80% of ASMD), which were kept in main plots and three plant population densities (D1: 10, D2: 20 and D3: 40 plants m?2), which were randomized in sub-plots. Significant interaction effects between irrigation regime and plant population density were detected for seed and oil yields, 1000-seed weight and seed weight plant?1 as well as WUE. The highest seed and oil yields were found for D2I1. Meanwhile, the highest WUE was found for D2I1 or D2I2. Based on these results, the combination of an irrigation rate of 50% of ASMD at a density of 20 plants m?2 when irrigation water supplies are sufficient or a rate of 65% of ASMD at the same plant density when irrigation water are limited, are recommended for planting safflower under similar soil and climatic conditions.  相似文献   
167.
This study was conducted to determine the effects of coconut water (CW) and activated charcoal (AC) on multiplication of Phalaenopsis gigantea protocorms. The protocorms used for this study were obtained by germinating seeds in vitro. Protocorms with trimmed and untrimmed bases were cultured on XER basal medium containing 0, 10, 15 or 20% (v/v) CW; and 0, 1, 2 or 2.5 g AC l−1. Trimmed protocorms exhibited the highest percentage of proliferation on a medium containing 15% (v/v) CW and 2.5 g AC l−1 (56.82 ± 38.86%) with an average of 4.24 ± 2.89 protocorms formed per protocorm. Untrimmed protocorms cultured on a medium containing 20% (v/v) CW without AC produced the highest percentage of new protocorms (6.93 ± 6.28%) with an average of 0.72 ± 0.57 per protocorm. When CW was added to a medium singly, 10% (v/v) CW induced a higher degree of proliferation on trimmed protocorms (5.68 ± 10.14%) with an average 0.50 ± 0.84 new protocorms per protocorm. Untrimmed protocorms proliferate to a much lower extent (2.57 ± 2.74%) with an average of 0.72 ± 0.57 protocorms per protocorm when cultured on a similar medium. A high concentration of CW enhanced proliferation on untrimmed protocorms, but increased mortality of trimmed protocorms. The addition of CW with AC to media increased protocorm proliferation and survival of both trimmed and untrimmed protocorms. When cultured on all media, trimmed protocorms produced a higher number of new protocorms (an average 0.5–7.0) as compared to untrimmed protocorms (0.3–1.9). Comparative studies showed that trimmed protocorms produced up to 10 times more new protocorms than untrimmed ones. Altogether this study showed that trimmed protocorms cultured on a medium containing CW and AC can be used for high-frequency multiplication of P. gigantea seedlings.  相似文献   
168.
Background

Toxoplasma gondii is a common protozoan parasite among all mammals, in particular small ruminants, worldwide. Traditional husbandry can be a major risk factor for infection of sheep and goats with this parasite.

Objectives

The present study aimed to determine the current status of the prevalence for T. gondii in livestock of Qazvin Province.

Methods

In this cross-sectional study, the sera of 455 sheep and 375 goats were examined to detect anti-Toxoplasma IgG antibodies by using in-house indirect ELISA.

Results

Overall, 33.62% (153/455) of sheep and 36.41% (130/375) of goats were positive for anti-Toxoplasma IgG antibodies with no statistically significant difference. The prevalence rate of T. gondii among the sheep of Qazvin County was significantly higher than in Abyek and Abhar counties (p < 0.001).

Conclusions

The results of the present study indicate that the prevalence of T. gondii in sheep and goats of the study area is high. Therefore, the meat of the animals reared in this area can be a potential source of human infections by this parasite.

  相似文献   
169.
In January 2011, symptomatic chickpea and faba bean plants were observed in fields located in the Gezira state (Sudan). Faba bean plants showed yellowing and stunting, whereas chickpea plants presented yellowing, reddening and little leaves. The disease etiology was investigated using nested polymerase chain reaction (PCR) with phytoplasma-specific primers which amplify a fragment of the 16S rRNA gene. Sequencing and restriction fragment length polymorphism (RFLP) analyses revealed that the tested phytoplasmas belonged to the group 16SrII. Phylogenetic analyses of the 16S rRNA gene of the obtained sequences indicated that the chickpea and faba bean phytoplasmas from Sudan were more closely related to the phytoplasmas subgroup 16SrII-D. To our knowledge, this is the first report of phytoplasmas from the group 16SrII-D infecting chickpea in Sudan, and faba bean worldwide.  相似文献   
170.
To clarify the effect of lactation period on ovarian follicular activity and associated hormonal levels in goats, six goats were monitored daily by ultrasonographic examination with blood sampling during early (Days 5 to 25; Day 0 was the day of kidding) and late (Days 40 to 60) lactation. While the presence of a corpus luteum of pregnancy retarded follicular growth in the ipsilateral ovary until Days 11-13 postpartum, the total follicular number (TFN) and area (TFA) increased during late lactation due to the significant increase in the number of medium- and large-sized follicles and decrease in the number of small follicles. Four goats showed a similar pattern of follicular development during the period studied characterized by the emergence of five and six waves during the early and late lactation, respectively. The largest follicle diameter of the first three waves monitored during early lactation was significantly smaller as compared with the diameter of those existing during late lactation. TFN showed a positive correlation with FSH but showed a negative correlation with immunoreactive (ir-) inhibin and estradiol during the postpartum period. TFA was positively correlated with ir-inhibin, estradiol and PRL and negatively correlated with FSH during the monitored periods. The plasma levels of ir-inhibin and progesterone were significantly higher during late lactation compared with the levels recorded during early lactation. Ir-inhibin levels showed a significant positive correlation with LH and estradiol during early and late lactation but showed a negative correlation with FSH during the whole lactation period. LH was positively correlated with estradiol and PRL during early and late lactation, respectively. These results suggest that the lactation period has a detrimental effect on ovarian activity during the early postpartum period in goats.  相似文献   
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