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51.
Land tenancy arrangements vary widely in the U.S. crawfish industry, including full ownership by the crawfish producer, cash leases, share leases, and combination cash-share leases. This study examines the array of tenancy arrangements available and analyzes the types of farmers selecting each using a multinomial logit model. Choice of tenancy arrangement varies according to a number of traditional factors, such as farm size, experience, specialization, and production system. The influence of production system on land tenancy selection is of particular interest. Crawfish-rice double-crop producers tend to own all of their crawfish land, while those farming under rotational systems with crawfish and field crops tend to select combination cash-share leases. Shares, rental rates, and percentages of pumping cost paid by the landlord vary widely.  相似文献   
52.
This paper suggests a new approach for providing intelligence in the system for diagnosis of diseases of the oilseed-crops. It reports the development of a web-based intelligent disease diagnosis system (WIDDS). The WIDDS is based on a new fuzzy logic approach. The approach is based on use of a rule-promotion methodology. This approach enables the drawing of inferences with the enhanced intelligence. The WIDDS also incorporates new features that improve the presently existing expert systems. The new features are (i) object-oriented (O-O) inference model, (ii) dynamic knowledge base creation strategy. The dynamically promoted rules are derived from those diagnosis sessions, which resulted in successful decisions. This enables more efficient decision-making in the future sessions, (iii) audio-visual-graphical user interface using text-to-speech (TTS) conversion tools. The WIDDS results in decreasing not only the number of interactive question-answer sessions with the clients but also leads to acceptable diagnosis. Further, the inferences are drawn faster compared to the traditional approach, which is the expert based reasoning method. The suggested WIDDS, which is based on rule-promotion approach, has been tested for three oilseeds crops - soybean, groundnut and rapeseed-mustard.  相似文献   
53.
The silphinenes are tricyclic sesquiterpenes that have antifeedant and toxic effects in insects and structural similarity to the known GABA antagonist, picrotoxinin. In murine synaptoneurosomes, silphinenes block GABA-stimulated influx of 36Cl with EC50s in the range of 10-30 μM. In insects, silphinenes were tested in neurophysiological recordings of central neurons from third instar Drosophila melanogaster larvae. Silphinenes reversed the blockage of neuronal firing induced by GABA, but had little effect below 100 μM. The structure-activity profile observed in the murine chloride flux assay was also observed in the larval neurophysiological assay, indicating little selectivity for the silphinenes. A reference silphinene was equally active on nerve preparations from the rdl strain of D. melanogaster, which is resistant to channel-blocking antagonists via an altered GABA receptor. This latter finding suggests that silphinenes interact with the insect GABA receptor in a manner somewhat different from PTX, and that rdl resistance in the field may have little effect on silphinene efficacy.  相似文献   
54.
Enterococci are widely distributed in the environment ranging from foods to humans and are gaining industrial importance due to their technological traits. In the present study, enterococci (Enterococcus faecium NCIM5363 (EF-63) and Enterococcus durans NCIM5427 (ED-27)) which are native to fish processing waste with an ability to produce lipase, protease and enterocin concomitantly were characterised. Lipase assay was performed by titrimetry and protease activity and was estimated using haemoglobin and casein as substrates in the presence of buffers at acidic, basic and neutral pH. Furthermore, enterocin produced by the isolates was characterised. Enterocin was also checked for its stability at different pH, temperature and proteolytic enzymes. Lipase production was found to be 22 and 10 U/ml in the absence of tributryin and increased to 40 and 24 U/ml in its presence for EF-63 and ED-27, respectively, indicating that the lipase produced is substrate dependent. Protease production was confirmed by protease assay, and the protease produced showed more affinity towards the acidic substrate. Enterocin produced was stable at low pH (2 to 3) and high temperature (121°C, 15 min) and had a molecular weight of approximately 6 kDa. It exhibited antibacterial activity against both Gram-positive and Gram-negative food-borne pathogens. Proteinase K inactivated enterocin completely, whereas trypsin did not. Novelty of this work lies in the immense industrial importance these cultures hold as they are capable of producing lipase, protease and enterocin apart from being useful in recovering proteins and lipids from fish processing wastes.  相似文献   
55.
The present study was aimed to investigate the relationship between selected morphological traits of teat and subclinical mastitis (SCM) in Frieswal crossbred dairy cows. A total of 1040 quarters from 261 lactating cows were evaluated for teat shape (bottle/fleshy/collapsed/conical/normal/pencil and short), teat-end shape (dished/flat/funnel/pocketed/pointed and rounded), teat orientation (aligned/misaligned) and teat position (front and rear; left-sided and right-sided). Each udder quarter was screened with California Mastitis Test (CMT) for the purpose of defining quarter health status. Data were analysed using Chi-square test and multivariable logistic regression procedure. An overall prevalence of SCM (CMT positive) at quarter level was 30.6%. Most of the teats had normal or cylindrical shapes (48%), dished teat-ends (40.7%), and aligned (central or squared) in orientation (65%). At bivariable level, significant association of SCM with teat shape, teat position, teat orientation, parity, and stage of lactation was observed (P < 0.05 to P < 0.001). Teat-end shapes showed some association with SCM (P = 0.07). Results of multivariable analysis showed that pencil-shaped teats were least associated with SCM (P < 0.05) as compared to other teat shapes. Prevalence of SCM was also higher in rear teats (P = 0.015), misaligned teats (P = 0.01), and cows in second or higher parities (P < 0.01) and late stage of lactation (P < 0.001). The results of the present study indicate that selected morphological traits of teat are associated with SCM in Frieswal crossbred cows; therefore, selection towards desirable morphological traits could help reduce mastitis in this breed.  相似文献   
56.
57.
Objectives: To report the repair of tibial diaphyseal fractures in 2 calves using a circular external skeletal fixator (CEF). Study Design: Clinical report. Animals: Crossbred calves (n=2; age: 6 months; weight: 55 and 60 kg). Methods: Mid‐diaphyseal tibial fractures were repaired by the use of a 4‐ring CEF (made of aluminum rings with 2 mm K‐wires) alone in 1 calf and in combination with hemicerclage wiring in 1 calf. Results: Both calves had good weight bearing with moderate lameness postoperatively. Fracture healing occurred by day 60 in 1 calf and by day 30 in calf 2. The CEF was well maintained and tolerated by both calves through fracture healing. Joint mobility and limb usage improved gradually after CEF removal. Conclusions: CEF provided a stable fixation of tibial fractures and healing within 60 days and functional recovery within 90 days. Clinical Relevance: CEF can be safely and successfully used for the management of selected tibial fractures in calves.  相似文献   
58.
In the present study, the effects of kinetin (KN; 10 and 100 μM) application under manganese toxicity (Mn; 50, 100 and 250 μM) were investigated, on growth, photosynthetic pigments, total protein, total nitrogen, ammonium (NH4+) content, NH4+ assimilating enzymes and antioxidant system in pea seedlings. The exposure of pea seedlings to Mn and 100 μM of KN alone and in combination, caused decrease in growth, photosynthetic pigments, total protein and total nitrogen contents, and an increase in NH4+ content. However, application of 10 μM of KN together with Mn reduced the Mn toxicity symptoms, promoted the growth of seedlings and led to the decrease in NH4+ content compared to Mn treatments alone. The root and shoot activities of glutamine synthetase (GS), glutamate oxoglutarate aminotransferase (GOGAT) and catalase (CAT) were decreased while glutathione reductase (GR) and dehydroascorbate reductase (DHAR) activities exhibited differential responses when pea seedlings were exposed to Mn and 100 μM of KN. However, under similar treatments, activities of glutamate dehydrogenase (GDH), superoxide dismutase (SOD) and ascorbate peroxidase (APX) in root and shoot were increased. It was noticed that addition of 10 μM of KN together with Mn, caused significant stimulation in activities of enzymes of NH4+ assimilation and antioxidant defense system even over their respective control values. Non-enzymatic antioxidants (ascorbate and glutathione) in root and shoot of pea seedlings exposed to Mn stress were significantly increased by the addition of 10 μM of KN. Therefore, ameliorative effect of 10 μM of KN against Mn toxicity was observed. This study thus suggests that 10 μM of KN appreciably improves Mn tolerance of pea seedlings under Mn toxicity while reverse effects were exhibited by 100 μM of KN.  相似文献   
59.
60.
This paper addresses the reasons why US meat goat producers selected to engage in meat goat production. A mail survey of US meat goat producers was conducted. Potential reasons for entering meat goat production included those associated with lifestyle, farm management, productivity, and economics. Reasons for entering meat goat production were assessed and analyzed using ordered probit models. The most important reasons for entering meat goat production included enjoyment working with goats, goat production fitting well into the farm management plan, goats could be raised on a relatively small acreage, goat grazing preferences were different from other species, and the family could be involved in the goat enterprise. The 12th and 13th most important reasons were goat production profitability and low cost associated with purchasing and raising goats. Larger-scale farmers were more likely to have selected meat goat production for profitability and productivity reasons while smaller-scale farmers were more likely to have selected it for lifestyle reasons. Farmer demographics, farm characteristics, and farm location also impacted reasons why the farmer selected the goat enterprise. Results have implications for development of the meat goat industry.  相似文献   
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