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61.
62.
This study was performed in 360 laying Bovans White hens and aimed to evaluate the effect of Carbo‐Amino‐Phosphate‐Chelates (CAFQ) as a mineral premix and its 30% reduction by compared to inorganic trace minerals (ITM) concerning its performance, egg quality, tibia breaking strength and immunity. Sixty‐week‐old hens were assigned into three treatments with 10 replicates of 12 birds each. Treatments were as follows: (a) (100% ITM), (b) (100% CAFQ) and (c) (70% CAFQ). Based on the results obtained during 12 weeks, under the current test conditions, improved yolk colour (p < 0.05); shell breaking strength (p < 0.05); and storage time (p < 0.05) were observed in hens fed with a diet reduced by 70% in CAFQ inclusion showed similar performance behaviour and better egg breaking strength regarding with ITM, suggesting the possibility of minimizing the inclusion of trace minerals in laying hen diets improving environmental impact, in contrast to the use of inorganic sources of minerals.  相似文献   
63.
Plant Foods for Human Nutrition - Complementary feeding starts at around six&nbsp;months of age because neither breast milk nor formula assure the proper nutrition of infants. Therefore, along...  相似文献   
64.
Tanjungides A (1) (Z isomer) and B (2) (E isomer), two novel dibrominated indole enamides, have been isolated from the tunicate Diazona cf formosa. Their structures were determined by spectroscopic methods including HRMS, and extensive 1D and 2D NMR. The stereochemistry of the cyclised cystine present in both compounds was determined by Marfey’s analysis after chemical degradation and hydrolysis. We also report the first total synthesis of these compounds using methyl 1H-indole-3-carboxylate as starting material and a linear sequence of 11 chemical steps. Tanjungides A and B exhibit significant cytotoxicity against human tumor cell lines.  相似文献   
65.
Summary A reverse of the delaying effect of gibberellic acid (GA3) was observed in in vitro tuberization of potato plantlets when the medium contained 0.8×10−5 M jasmonic acid (JA). The promoting effect of JA seemed to be correlated with the initial absence of growing roots, probably through direct activity of JA in microtuber-producing buds in the stoloniferous shoots. This is based on the fact that JA did not inhibit root growth a posteriori. Endogenous gibberellins (GAs) synthesized by roots did not interfere with the previous activity of JA in tuberization. The absence of a JA promoting-effect on tuberization of previously-rooted plantlets could be related to the capacity of potato roots to synthesize endogenous GAs which might antagonize the JA effect on buds of stoloniferous shoots.  相似文献   
66.

Background  

A key challenge for conservation biologists is to determine the most appropriate demographic and genetic management strategies for wildlife populations threatened by disease. We explored this topic by examining whether genetic background and previous pathogen exposure influenced survival of translocated animals when captive-bred and free-ranging bighorn sheep (Ovis canadensis) were used to re-establish a population that had been extirpated in the San Andres Mountains in New Mexico, USA.  相似文献   
67.
The use of wrapped forage bales with high dry‐matter (DM) content implies risk of fungal growth inside the wrapping, and impaired feed quality. Since fungi may be unevenly distributed in bales, the method of sampling can influence the outcome of the analysis. Three common sampling methods for detection of fungi in wrapped forage were compared: direct plating of visible mouldy patches on bale surfaces (Method I), direct plating of pieces of foliage from drilled core samples (Method II) and quantitative analysis dilution series of drilled core samples (Method III). All samples were cultured on two media at two temperatures. Samples were collected from 124 farms in Sweden and Norway. Using Methods I, II and III, fungi were detected on 52%, 77% and 56% of the farms respectively. Fifty‐two fungal species were identified using a combination of culturing and molecular methods. The most predominant species were Arthrinium spp., found on 55% of the farms, followed by Penicillium roqueforti at 48% of the farms. Incubation at 25°C resulted in higher numbers of all genera, except Aspergillus, compared to incubation at 37°C. The different methods of sampling and culturing did not identify the same fungal species within the same bale. Analysing one bale per farm resulted in detection of less than half the number of species compared to analysing three bales. Of the sampling and culturing methods compared, direct plating of drilled core samples cultivated at malt extract agar at 25°C performed best in terms of qualitative analysis of fungi species.  相似文献   
68.
Plant Foods for Human Nutrition - Sorghum is a major cereal crop with various agronomic advantages, contains health-promoting compounds and is gluten-free. There is a growing tendency to use...  相似文献   
69.
Plant Foods for Human Nutrition - Silver linden (Tilia tomentosa Moench, TtM) flowers possess several health-promoting properties, especially at the neurological level, such as intestinal...  相似文献   
70.

Background

Efficient division of reproductive labor is a crucial characteristic of social insects and underlies their ecological and evolutionary success. Despite of the harmonious appearance of insect societies, nestmates may have different interests concerning the partitioning of reproduction among group members. This may lead to conflict about reproductive rights. As yet, few studies have investigated the allocation of reproduction among queens in multi - queen societies ("reproductive skew"). In the ant Leptothorax acervorum, reproductive skew varies considerably among populations. While reproduction is quite equally shared among nestmate queens in most populations from boreal Eurasia (low skew), colonies from populations at the edge of the species' range are characterized by "functional monogyny," i.e., high skew. The proximate mechanisms underlying high skew, in particular how workers influence which queen lays eggs, are not well understood. We investigated the behavior of queens and workers in functionally monogynous colonies of L. acervorum from two mountain ranges in central Spain.

Results

We provide evidence for both queen and worker influence on the outcome of conflict over reproduction in colonies of L. acervorum from Spain. The patterns of queen - queen aggression and worker - queen grooming and feeding after hibernation allowed predicting, which queen later began to lay eggs. In contrast, worker aggression towards queens was not clearly associated with a queen's future reproductive success. Queen - queen and worker - queen aggression differed in quality: queens typically engaged in ritualized dominance behavior, such as antennal boxing, while workers also attacked queens by biting and prolonged pulling on their legs and antennae. In several cases, overt worker aggression led to the expulsion of queens from the nest or their death.

Conclusion

We conclude that queens of L. acervorum from Spain establish rank orders by ritualized dominance interactions, such as antennal boxing. Workers may reinforce these hierarchies by preferentially feeding and grooming high ranking queens and attacking lower ranking queens. Aggressive worker policing may thus stabilize functional monogyny. Optimal skew models predict that high skew in ants is associated with high dispersal costs. In central Spain, L. acervorum is restricted to small patches at higher elevations, which presumably makes dispersal and colony founding difficult. Because of the ecological requirements of L. acervorum and the predicted large impact of global change on central Spain, the functionally monogynous populations of this ant must be considered as threatened.  相似文献   
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