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31.
Environmental concern accelerated development of new wood preservatives having low mammalian toxicity in addition to high protective effectiveness. PHN 130 and PHN 130 G have been developed recently by KOHMIX Ltd. in Japan as environmentally safe, fire-proof boron containing compounds. Beyond their proved fire-proof properties, stability of loaded chemical in wood at humid service conditions and decay resistance are required to be known for effective and broad use of these compounds in wood preservation. Results indicated that PHN imparted complete decay resistance to wood against brown- and white-rot fungi Tyromyces palustris and Coriolus versicolor, respectively. Protection efficacy of PHN also continued despite severe weathering conditions provided that impregnation is done by an undiluted solution. PHN 130 G appeared more effective than PHN 130 in this respect. However, both compounds were leachable from treated wood regardless of retention level or physical restriction of water access into wood by compression.This revised version was published online in April 2005 with a corrected date of receipt of the article.
Ergün BaysalEmail: Phone: +90-252-2238612Fax: +90-252-2238511
  相似文献   
32.
Infection of heartwood by decay fungi (heartrot) is a concern for growers of Acacia mangium for solid‐wood products as the incidence can be high in some regions of Indonesia. Variation of heartrot incidence for different provenances of A. mangium was determined using two field trials in Sumatra, Indonesia. In a Riau Province trial of 21 provenances, the effect of provenance was statistically significant for natural heartrot incidence, which ranged from 1.6% to 27.2%. In a smaller trial using artificial inoculation in South Sumatra, heartwood infection incidence ranged from 39.4% to 70.8% across six provenances and both wound type and provenance were statistically significant factors. There was also significant variation in sapwood infection length related to provenance. Wood extractives (yield, total phenols, protein‐precipitable tannin and 2,3‐trans‐3,4′,7,8‐tetrahydroxyflavanone) were quantified from a subsample of trees for each trial. However, no significant differences in extractive concentration were detectable according to provenance and evidence for a relationship between heartwood extractives and heartrot incidence was generally poor. While further studies need to be completed to establish the basis for heartrot incidence, results from these trials allow for recommendations on provenance selection to reduce heartrot incidence and provide information for further genetic selection programmes.  相似文献   
33.
Tissue culture micropropagation of Douglas-fir   总被引:1,自引:0,他引:1  
A procedure was developed for plantlet production from embryos of Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco]. The Medium for Conifer Morphogenesis, used at full strength, and supplemented with 10 M benzyladenine for 17 days produced an average of 6.8 shoots on more than 90% of the embryos. The percentage of shoot-forming embryos as well as the average number of shoots per embryo varied significantly among eight seedlots. For secondary multiplication, 89% of the adventitious shoots produced axillary buds on MCM with 5 M benzyladenine. However, 0.5 M BA was more suitable for the elongation of axillaries. Rooting ranged from 0–87% depending upon the treatment. The highest percentage was obtained with a 7-week incubation in peat:perlite containing 1/5-strength medium, 1% sucrose and 2.7 M naphthaleneacetic acid, followed by 5 weeks on peat:perlite with 1/5-strength major and minor salts, full iron and organics, 1% sucrose and 0.1% charcoal.  相似文献   
34.
The responses of juvenile leaves of two Eucalyptus species, with contrasting susceptibility to infection by Mycosphaerella leaf disease, were compared. The anatomical changes, accumulation of phenolics, suberin, lignin and anthocyanin and the retention of chlorophyll were studied in leaf lesions of varying developmental stages caused by species of Mycosphaerella. Enhanced resistance of Eucalyptus nitens in southern Australia was attributed to the formation of an effective lignified and suberized necrophylactic periderm, to restrict pathogen spread. Leaves of E. nitens contained isobilateral palisade which resulted in both abaxial and adaxial cell division and the initiation of a strong reinforced cellular zone from an early lesion stage. Eucalyptus globulus formed a slower, distorted necrophylactic periderm through hypertrophic changes to existing mesophyll and limited cell divisions of the single adaxial palisade layer. Deposits of lignin and suberin did not occur until later in lesion development, which were not effective in preventing further disease development. From this study it is hypothesized that tolerance of eucalypts to Mycosphaerella pathogens may be associated with constitutive mesophyll density.  相似文献   
35.
Two trials were performed to assess the meat fatty acid profile of goat kids from different genotypes, production systems and sex. In the first trial, genotype effect was determined in 24 suckling male kids from Turkish Saanen, Maltese and Gokceada breeds. In the second trial, male and female Gokceada Goat kids were used to compare the effect of extensive and semi‐intensive production systems on fatty acid composition of meat. Significant genotype effect was observed in the percentages of myristic acid (C14:0), palmitic acid (C16:0), oleic acid (C18:1 n‐9), linolenic acid (C18:3 n‐3), arachidonic acid (C20:4 n‐6) and docosahexaenoic acid (C22:6 n‐3), despite no differences on the ratios of polyunsaturated fatty acids to saturated fatty acids (PUFA/SFA) and n‐6/n‐3 (P > 0.05). The effect of production system had also significant effects on fatty acids, but sex only influenced significantly stearic acid (C18:0), C18:1 n‐9 and C18:3 n‐3 fatty acids and total PUFA level and PUFA/SFA ratio. This study confirms that dairy breeds are prone to produce higher levels of unsaturated fatty acids in their muscle. Meanwhile, meat from Gokceada goat kids, which is one of the indigenous breeds in Turkey, had similar PUFA/SFA and n‐6/n‐3 ratios to Turkish Saanen and Maltase.  相似文献   
36.
Two anti-inflammatory omega-3 polyunsaturated fatty acids (PUFAs) of stearidonic acid (SA) and eicosapentaenoic acid (EPA) and one pro-inflammatory omega-6 PUFA of arachidonic acid (AA) were isolated from the edible brown seaweed Undaria pinnatifida. SA was active against mouse ear inflammation induced by phorbol myristate acetate, with IC50 values of 160, 314, and 235 microg per ear for edema, erythema, and blood flow, respectively. EPA was also active against edema, erythema, and blood flow, with IC50 values of 230, 462, and 236 microg per ear, respectively. Although AA at low concentrations showed anti-inflammatory activities when measured 10 h later, AA doses of more than 243 microg per ear induced inflammatory symptoms 1 h later. Mature thalli generally had larger amounts of PUFAs than young thalli. The algal blade contained more omega-3 PUFAs than were found in other parts, while the holdfast contained extremely high amounts of AA. Late-season thalli showed increased amounts of PUFAs, especially AA.  相似文献   
37.
Abstract In an attempt to identify appropriate feeding rates for multispecies of fish raised in fertilized earthen ponds, the present work was conducted over a 19‐week experimental period to establish the growth performance, production and body composition of Nile tilapia, common carp and silver carp fed 0.0%, 0.5%, 1.0%, 3.0%, 5.0% biomass and to apparent satiation (treatments). Twelve ponds were stocked with a similar number and weight of each fish species. Two ponds were assigned to each of the treatments, and a 25% protein pelleted fish feed was used to feed fish at the specified rate of feeding. At the end of the experiment, growth, weight gain, survival, yield and body composition of fish groups were affected by the treatments. The economic effectiveness also varied among treatments. The most conspicuous attribute of the feeding rates was its lack of influence on growth (g day?1), weight gain (g per fish), yield (kg ha?1) or body composition of silver carp. The results of whole‐body proximate analysis indicated that various feeding rates had either an irregular pattern or no effects on the protein and ash gain per 100 g of fish body weight (bw) gain. The most notable exceptions were significant (P < 0.05) increases in body fat and gross energy gains in Nile tilapia, common carp and silver carp accompanied by decreases in percentages of moisture (but not in silver carp) as feeding rate increased. Among the six different feeding levels, feeding to apparent satiation (feed amount was equivalent to 2.67% of fish bw day?1) appeared to be optimal, as it significantly (P < 0.05) supported the highest fish production, income and net profit compared with all other treatments except for the 3% feeding level, for which the differences in those measurements were comparable.  相似文献   
38.
39.
In this study, Intraperitoneal (IP) and bath immersion (BI) vaccine trials were conducted in fish with a mean weight of 6.3 g. Rainbow trout vaccinated with lipopolysaccharide (LPS) was 50 mg/L protein concentration and challenged by IP injection with 9.8 × 106 cell/ml of Yersinia ruckeri at 45 days post-immunization had a relative percent survival (RPS). To obtain an effective bath immersion vaccine against yersiniosis, LPS preparation was obtained from the Y. ruckeri and with the LPS antigen. After 28 and 60 days vaccinated fish with first and second immunizations by LPS were challenged via intraperitoneal injection with 9.8 × 106 cell/ml of Y. ruckeri for evaluating the mortality rates and calculating the relative percentage of survival (RPS). RPS value of experimental groups, which was significantly (P < 0.05) larger than that of the control group.  相似文献   
40.
The experiment was conducted to determine the supplementary feeding value of ground Prosopis juliflora pod (Pjp) and cottonseed meal (CSM) and their mixtures on feed intake, body weight gain and carcass parameters of Afar sheep fed a basal diet of pasture hay. Twenty-five yearling fat-tailed Afar rams with mean initial live weight 17.24?±?1.76 kg (mean ± SD) were used in a randomized complete block design. Animals were blocked on their initial body weight. The experiment was conducted for 12 weeks and carcass evaluation followed. Treatments were hay alone ad libitum (T 1) or with 300 g CSM (T 2), 300 g Pjp (T 5), 2:1 ratio (T 3) and 1:2 ratio of CSM : Pjp (T 4). The CP contents of the hay, CSM and Pjp were 10.5, 44.5 and 16.7 %, respectively. Hay DM intake was higher (P?<?0.05) for non-supplemented and total DM intake was lower in non-supplemented. Average daily weight gain (ADG) was lower (P?<?0.05) for T 1 compared to all supplemented treatments except T 5. Hot carcass weight and rib-eye muscle area also followed the same trend like that of ADG. Compared with feeding hay alone, supplementing with CSM or a mixture of CSM and Pjp appeared to be a better feeding strategy, biologically, for yearling Afar rams.  相似文献   
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