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71.
This study is aimed at assessing the ability of two endophytic bacteria originally isolated from healthy oil palm roots, Pseudomonas sp. (UPMP3) and Burkholderia sp. (UPMB3) to induce resistance in susceptible Berangan banana against Fusarium oxysporum race 4 (FocR4). Increased accumulation of resistance-related enzymes such as peroxidase (PO), phenylalanine ammonia lyase (PAL), lignithioglycolic acid (LTGA), and pathogenesis-related (PR) proteins (ehitinase and β-1,3-glucanase) has been observed in plantlets treated with endophytic bacteria UPMP3 and UPMB3 singly or as mixture under glasshouse conditions. Pre-inoculation of banana plantlets with UPMP3 showed a significant reduction in Fusarium wilt incidence 72 d after challenged inoculation with FocR4. UPMB3 was less effective in suppressing Fusarium wilt compared to UPMP3, whereas, the mixture of both endophytes showed an intermediate effect. Based on these results, it is concluded that UPMP3 could be a promising biological control agent that can trigger resistance against Fusarium wilt in susceptible Berangan banana.  相似文献   
72.
Previously, the distribution of myoepithelial cells (mecs) in the salivary glands was studied by both immunohistochemistry, and transmission electron microscopy; however, little was elucidated concerning their morphological features, especially in goats. This study was performed to investigate the correlation between the cytoarchitecture of the mecs in goat major salivary glands (parotid, mandibular, and sublingual glands) and the nature of the saliva secretion. The cytoarchitectural features of the mecs were examined by scanning and transmission electron microscopy as well as immunohistochemically. The secretory endpieces in the parotid gland are of the pure serous type, but in both the mandibular and sublingual glands they are of the mixed type. In all studied glands, the intercalated ducts were covered by mecs which, unlike the large stellate cells that surrounded the secretory endpieces, were spindle-shaped with few cytoplasmic processes. Interestingly, the mecs were found to bulge on the basal surfaces of the serous acini and intercalated ducts in all glands and to be in close contact to the seromucous tubules surface in the mandibular and sublingual glands forming a continuous network around it. In conclusion, the differences in the degree of development of the mecs as well as the number of their cytoplasmic processes may be correlated with the nature of the secretion and the number of the secretory granules. Thus these observations may have some relevance in the diagnosis of atrophy and pathogenic conditions of these glands.  相似文献   
73.
Two new withanolides named mandragorolide A (1) and mandragorolide B (2) were isolated from the MeOH extract of the whole plant of Mandragora officinarum of Jordanian origin, along with five known withanolides namely larnaxolide A (3), withanolide B (4), datura lactone 2 (5), withanicandrin (6) and salpichrolide C (7). Compound 3 has been reported only once before, from the leaves of Larnax glabra. This is the first report of withanolides of different biogenetic types from the genus Mandragora. Isolation of known fatty compounds, coumarins, sterols and tropane alkaloids was also achieved in this study.  相似文献   
74.
Hyacinth bean (Lablab purpureus L.) serves as a good source of vegetable proteins in human diet. Its seeds and pods contain as much as 20–28% protein. Besides, it contains tyrosinase enzyme, which has potential use in the treatment of hypertension. Phosphorus deficiency causes a serious yield and quality constraint of beans at Aligarh, Western Uttar Pradesh, India. To address the problem, a pot experiment was conducted to study the effect of basal phosphorus application on the agricultural performance of this medicinal legume. The plants were grown in pots containing soil supplied with five levels of phosphorus viz. 0, 25, 50, 75 and 100 mg P kg−1 soil as potassium dihydrogen orthophosphate (KH2PO4). The growth and other physiological attributes, leaf nutrient contents, nodule-nitrogen and leghemoglobin content were studied at 60, 90 and 120 days after sowing (DAS), photosynthesis and other related parameters were measured at 90 DAS and yield and quality attributes were recorded at harvest (150 DAS). Nitrate reductase and carbonic anhydrate activities, leaf-N, -P, -K and -Ca contents and nodule-nitrogen and leghemoglobin contents reached the maximum extent at 60 DAS. At 90 and 120 DAS, the values decreased significantly. Chlorophyll content, carotenoids content, and photosynthesis were at maximum level at 90 DAS. At various growth stages, phosphorus application at 75 mg P kg−1 soil resulted in maximum amelioration of most of the parameters studied. It increased the seed-yield by 38.3%, seed-protein content by 14.9% and seed-carbohydrate content by 5.0%, relative to the control. It was concluded that there was a hidden hunger of hyacinth bean for phosphorus owing to soil-phosphorus deficiency that was ameliorated effectively by its basal dressing at 75 mg P kg−1 soil.  相似文献   
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77.
In the present study, the preparation of sorbent from waste-derived siliceous materials has been investigated for the removal of nickel ion (Ni2+) from aqueous solutions. Three types of ashes, i.e., rice husk ash (RHA), palm oil fuel ash (PFA), and coal fly ash (CFA), were used in the preparation of sorbent. Batch studies were carried out to examine the effect of various experimental parameters, i.e., RHA/CFA/PFA ratio in the sorbent preparation, contact time, initial concentration of Ni2+, agitation rate, and pH. Among all the ratios of the prepared sorbent, it was found that sorbent containing RHA and PFA gave the highest Ni2+ removal efficiency. The optimum conditions for Ni2+ removal using RHA/PFA sorbent were obtained at contact time of 30?min, Ni2+ concentration of 100?mg/L, agitation rate of 130?rpm, and pH?4. During the optimum condition, more than 90% of Ni2+ could be removed in all experiment studies. It was also found that the spent RHA/PFA sorbents had a narrow range of particle size distributions as compared to prepared RHA/PFA sorbent. In addition, the surface morphology of the spent RHA/PFA sorbents had more compact structures.  相似文献   
78.
The effects of sun-drying cowpea seeds for three hours on cement (CS), wood (WS), and corrugated iron sheet (CIS) surfaces and packaging separately in polyethene and jute bags were studied. Moisture-gain, and resistance to insect and mold damage were monitored monthly for six months, while proximate analyses on day zero and at the 6th month were conducted. Results showed that the three-hour sun-drying of cowpea seeds on reflective surfaces (CIS and CS) enhanced the rate of moisture-reabsorption during storage and consequently, the degree of mold and insect damage irrespective of the packaging material employed. Crude fat, fiber and ash contents, unlike protein and moisture contents, remained virtually constant (p 0.05). In this study, the wood surface and polyethene bag were the most preferred treatments to store sun-dried cowpea seeds for about 5.7 months.  相似文献   
79.
The bioavailability of iron from local plants(black cumin seeds, milk thistle seeds, sesame seedsand thyme leaves) was investigated. Apparentabsorption of iron was calculated by subtracting fecal iron(using total collection of feces) from iron intake inSprague-Dawley rats. Two trials of animal feeding wereperformed. Liver and serum concentrations of iron, andserum hemoglobin concentration were taken as responseparameters for the bioavailability. Dry thyme wasparticularly rich in iron (117.2 mg/100 g dry matter)and milk thistle seeds in crude fiber (25 g/100 g drymatter). Rats fed the dry thyme diet or thatsupplemented with 5% egg white died but when the dietwas supplemented with 10% egg white, the animalssurvived. Iron intake and apparent and total ironabsorption were highest for the rats fed the drythyme-egg white diet. Liver weights for the groups fedblack cumin seeds and dry thyme were significantlyhigher (p < 0.05) than those for the groups fed milkthistle and sesame seeds. Liver content of ironwas highest for the animals fed black cumin seeds.Serum iron content increased significantly (p < 0.05)for the animals fed black cumin seeds, and serumhemoglobin concentration increased significantly (p < 0.05) in the groups fed milk thistle seed and blackcumin seed diets, but decreased for the group fed thethyme-egg white diet. It is concluded from this studythat iron was better utilized from black cumin seedsas indicated by liver storage of iron. On the otherhand, thyme had the highest iron absorption but lowestutilization.  相似文献   
80.
This study determined the prevalence of Cryptosporidium spp. oocysts in faecal samples from elephant (Loxodonta africana), buffalo (Syncerus caffer) and impala (Aepyceros melampus) in the Kruger National Park (KNP) and an adjacent game reserve in South Africa. Two of the study areas were in close proximity to rural communities on the western KNP boundary and the third study area was located in the centre of the KNP. Fresh stool samples (n=445) were collected and tested using an immunofluorescent antibody test (IFA) for Cryptosporidium parvum. A total of 278 of these were randomly selected (approximately 90 samples per wildlife species) and tested with the modified Ziehl Neelsen staining technique (ZN) for Cryptosporidium spp. The prevalence of Cryptosporidium spp. was highest in elephants (25.8% [95% confidence interval: 17.3, 35.9]), compared to buffalo (5.5% [1.8, 12.4]) and impala (4.3% [1.2, 10.5]). C. parvum showed similar patterns, being most prevalent in elephants (4.2% [1.5, 8.8]), compared to buffalo (1.4% [0.2, 5.1]) and impala (1.9% [0.4, 5.3]). 29 samples, including ZN positive and IFA positive samples, were retested using a real time PCR (rtPCR) technique. Of the 28 ZN-positive samples, 14 (50%) were positive with rtPCR and of the 9 IFA-positive samples 6 (67%) were confirmed positive by rtPCR. The prevalence of Cryptosporidium oocysts was significantly higher in both of the two study areas adjacent to the western KNP boundary compared to the area in the centre of the KNP (OR=3.2 [1.2, 9.0]; P=0.024). Our study demonstrates for the first time the presence of Cryptosporidium spp. in wildlife in South Africa. The transmission of this parasite between wildlife, domestic animals and humans is a plausible hypothesis and represents a potential risk for immunodeficient human populations.  相似文献   
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