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91.
Candidate genes have been associated with milk production in bovines, such as the diacylglycerol O-acyltransferase 1 (DGAT1) and leptin (LEP); however, they have not been simultaneously investigated nor have been evaluated in the Brazilian Girolando breed (Gir × Holstein, backcrossed to Holstein). Our aim was to determine the influence of fat-related genes, DGAT1 and LEP, and their polymorphisms on performance traits of milk production in the Girolando breed. Results indicated that the K allele of the DGAT1 gene showed a significant association with total and average daily milk production with additive effect. The LEP gene showed that the A allele and its homozygote are highly prevalent and almost fixed in this population and may have been favorably selected during backcrossing for the origin of this breed. The important impact of the K allele of the DGAT1 gene on milk production corroborates the initiative of performing marker-assisted selections with this gene in breeding programs of the Girolando breed.  相似文献   
92.
The present investigation was intended to show a different immunohistochemical profile of matrix metalloproteinase-2 and Tissue inhibitor metalloproteinase-2 in bovine uteri with adenomyosis during follicular phase. Uterine samples of 32 cows in reproductive age were taken from the medial third of one of the uterine horns and grouped according to the adenomyosis degree (superficial and deep). Tissue sections (4 μm) were incubated overnight at 4°C with monoclonal antibody for matrix metalloproteinase-2 and Tissue inhibitor metalloproteinase-2. Staining intensities were evaluated in the luminal epithelium, ectopic and dystopic endometrial tissue (stroma, capillaries and glands), endometrial-myometrial border, myometrium, myometrial vessels (middle tunic and endothelium). The matrix metalloproteinase-2 expression was higher for deep adenomyosis samples, showing a differential mean reactivity in superficial endometrium, myometrial vessels, myometrium adjacent to adenomyotic focus and endometrial-myometrial border (P < 0.05). Moreover, matrix metalloproteinase-2 expression was higher in deep adenomyosis samples than that of Tissue inhibitor metalloproteinase-2 in almost all uterine structures analyzed (except for the endometrial and myometrial vessels and endometrial-myometrial border). The opposite was observed in the follicular phase, for both normal specimens and with superficial adenomyosis, where Tissue inhibitor metalloproteinase-2 expression was higher than that of matrix metalloproteinase-2. In conclusion, a differential pattern of matrix metalloproteinase-2 and Tissue inhibitor metalloproteinase-2 was observed in cow uteri with adenomyosis.  相似文献   
93.
In developing countries such as Brazil, where canine rabies is still a considerable problem, samples from wildlife species are infrequently collected and submitted for screening for rabies. A collaborative study was established involving environmental biologists and veterinarians for rabies epidemiological research in a specific ecological area located at the Sao Paulo State, Brazil. The wild animals’ brains are required to be collected without skull damage because the skull’s measurements are important in the identification of the captured animal species. For this purpose, samples from bats and small mammals were collected using an aspiration method by inserting a plastic pipette into the brain through the magnum foramen. While there is a progressive increase in the use of the plastic pipette technique in various studies undertaken, it is also appreciated that this method could foster collaborative research between wildlife scientists and rabies epidemiologists thus improving rabies surveillance.  相似文献   
94.
Lactobacillus sp. are important inhabitants of the intestines of animals. They are also largely used as probiotics for both humans and animals. To exert beneficial effects, lactobacilli have to survive through the gastrointestinal transit. Based on bile-salt resistance, pH tolerance, antimicrobial activity and heat resistance, Lactobacillus plantarum 4.1 and Lactobacillus reuteri 3S7 were previously selected and used as probiotic additives in pelleted feeding trials. Both strains were fed to pigs (sows and piglets) at a cell number of ca. 10(10) viable cells per day. A polyphasic approach, comprising growth on selective media, Biolog System analysis, 16S rRNA gene sequencing and RAPD-PCR typing, was used to identify and differentiate L. plantarum 4.1 and L. reuteri 3S7 from other faecal Lactobacillus sp., L. plantarum 4.1 and L. reuteri 3S7 had the capacity to survive during the gastrointestinal transit and were found in the feaces at a cell number of 6-8 log cfu/g. Their persistence was shown after 6 days from the administration. Compared to untreated pigs, the administration of L. plantarum 4.1 and L. reuteri 3S7 significantly (P<0.05) decreased the population of Enterobacteriaceae. Besides, the beta-glucuronidase activity of all pigs decreased of ca. 23.0% during administration. The findings of this study showed that L. plantarum 4.1 and L. reuteri 3S7 have the potential to be used as probiotic additives in pelleted feed for pigs.  相似文献   
95.
The coffee berry borer (CBB), Hypothenemus hampei Ferrari (Coleoptera: Curculionidae), is the most important coffee pest in most of the coffee growing countries. CBB females leave old dry berries after harvest and search for dry noninfested berries on the plant or on the ground to lay eggs or to use as refuge until new berries are available on the coffee trees in the following season. The CBB infestation level and emergence from berries on the ground or on the plants were evaluated in two fields post-harvest in the Spring in Brazil over two seasons. Twenty infested or noninfested berries in separate cages (250 ml plastic cups) were placed on the plants or on the ground under the tree canopy, in each field. The number of infested berries and CBB females that emerged from the infested berries were recorded weekly. CBB emergence was higher from berries on the ground than those on the coffee trees in both seasons, whereas CBB infestation was higher on coffee berries on the plants than those on the ground in season I. Insolation (hours of sunlight) and temperature were the main covariates that affected emergence and infestation by this insect. The results are discussed for monitoring CBB during the time of dispersal with implications on integrated management of this pest.  相似文献   
96.
This study aimed to investigate the cardiovascular effects elicited by Dictyota pulchella, a brown alga, using in vivo and in vitro approaches. In normotensive conscious rats, CH(2)Cl(2)/MeOH Extract (CME, 5, 10, 20 and 40 mg/kg) from Dictyota pulchella produced dose-dependent hypotension (-4 ± 1; -8 ± 2; -53 ± 8 and -63 ± 3 mmHg) and bradycardia (-8 ± 6; -17 ± 11; -257 ± 36 and -285 ± 27 b.p.m.). In addition, CME and Hexane/EtOAc Phase (HEP) (0.01-300 μg/mL) from Dictyota pulchella induced a concentration-dependent relaxation in phenylephrine (Phe, 1 μM)-pre-contracted mesenteric artery rings. The vasorelaxant effect was not modified by the removal of the vascular endothelium or pre-incubation with KCl (20 mM), tetraethylammonium (TEA, 3 mM) or tromboxane A(2) agonist U-46619 (100 nM). Furthermore, CME and HEP reversed CaCl(2)-induced vascular contractions. These results suggest that both CME and HEP act on the voltage-operated calcium channel in order to produce vasorelaxation. In addition, CME induced vasodilatation after the vessels have been pre-contracted with L-type Ca(2+) channel agonist (Bay K 8644, 200 nM). Taken together, our data show that CME induces hypotension and bradycardia in vivo and that both CME and HEP induce endothelium-independent vasodilatation in vitro that seems to involve the inhibition of the Ca(2+) influx through blockade of voltage-operated calcium channels.  相似文献   
97.
The aim of the research was to show how a change in land use influences the structure of a dung beetle assemblage and affect its conservation. In the Pineto Urban Regional Park (Rome), dog dung is the sole food resource currently available for scarab dung beetles, after the recent removal of wild and domestic herbivores. A one-year sampling was conducted to study the scarab assemblage in dog scats (1999) and to compare it with the previous assemblage associated with sheep droppings (1986). Richness, evenness and similarity parameters were compared between the two allochronic assemblages. From sheep to dog dung, an impoverishment of the total richness was observed (from 19 to 9 species) together with an increase of individuals (by 7 times). Dog dung harboured 20% of the current scarab dung beetle fauna of Rome, probably as a consequence of the dog mixed diet, rich in cellulose. Both the communities showed a high percentage of tunnellers, probably because of the food shortage and, for dog scats, of the high dehydration rate. A comparison with other Roman scarab communities enhanced that: (1) the change in food resource determined a higher difference in species composition respect to other parameters (size and habitat diversity); (2) dog dung provided a temporary refuge for species that otherwise may encounter local extinction in urban environments.  相似文献   
98.

Purpose

The present study investigated lake and river sediments affected by metals from an acid mine drainage (AMD) from a former uranium mine. The role of bacterial sulfate reduction in the immobilization of contaminants was evaluated, and the analyses of acid volatile sulfide (AVS) and sequential extraction were performed. Consequently, the potential mobility and bioavailability of contaminants were established.

Materials and methods

Sulfur isotopic fractionation (δ34S), AVS, and sequential extraction procedure were used to assess the sulfate bacterial reduction and the availability of contaminants in the environment at six sampling stations.

Results and discussion

The δ34S indicated that bacterial reduction is a key process in the natural attenuation of contamination in the Águas Claras reservoir, precipitating metal sulfides. According to the USEPA criteria, adverse biological effects are expected for sample S1 (inside the reservoir) which is likely to be toxic, while for sediment S4 (in the river), the toxicity is uncertain. The other samples were classified as non-toxic, likely because of the decreased solubility of zinc sulfide. A decrease in the concentration of the contaminants downstream of the reservoir was observed. The predominance of U (0.4 %) in the labile fraction and the elevated concentrations of Zn (0.5 %) and Mn (0.7 %) in the sediments inside the reservoir raises concerns regarding the availability of these contaminants in the environment.

Conclusions

The main environmental impact appears to be concentrated in the Águas Claras reservoir, whereas the Antas creek does not seem to be affected by the AMD process. Although the bacterial sulfate reduction is effective in its production of sulfides capable of immobilizing the contaminants, the presence of Zn and U in the labile and reducible fraction is a matter of concern due to its long-term bioavailability. Thus, continuous monitoring of the redox potential of the waters and sediments, mainly in the reservoir, is recommended in order to assess and possibly prevent later dissolution of sequestered contaminants.
  相似文献   
99.
Genetic Resources and Crop Evolution - Jatropha (Jatropha curcas L.) is an oleaginous potential, howetever, some studies report that there is low genetic diversity in Brazilian genotypes....  相似文献   
100.
Abstract

A greenhouse study was conducted to evaluate the long‐term availability of radiocesium (Cs‐137) to various crops grown on contaminated soil that were limed to pH 6.8 (LIME) or were limed and Zn‐ and Mn‐EDTA chelates added (LIME + CHELATE). Crops were grown either continuously or followed a cropping sequence. Continuously grown clover and bahiagrass accumulated the most Cs‐137 with levels exceeding 2,000 pCi/g dry weight in bahiagrass. Uptake of Cs‐137 was depressed by both the LIME and LIME + CHELATE treatments. Uptake was usually greatest during the first three years but only in unlimed soil. Cesium‐137 is about 3 to 8 times higher in soybean beans than in wheat grain. Uptake of Cs‐137 by plants from contaminated soil can be expected to be high in acidic soils, especially in the absence of lime treatment.  相似文献   
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