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91.
Yoshio Kijidani Naoki Ohshiro Junji Matsumura Shinya Koga 《Journal of Wood Science》2014,60(4):235-242
Indole acetic acid (IAA) was believed to be an important regulator in xylem formation in conifers. However, few studies have been done on the endogenous amount of IAA in cambial region tissues in sugi (Cryptomeria japonica) trees. In this study, we report the IAA amounts in the lower and upper trunk of mature sugi cultivars (Kumotoshi, Yaichi and Obiaka) in September, and the effects of growth traits on the IAA amounts. The effect of height position (lower or upper trunk) on IAA amounts was found to be larger than that of genetic variation (Kumotoshi, Yaichi or Obiaka) by two-way ANOVA. There was no significant interaction effect (genetic variation × height position). The IAA amounts of all trees varied from 3 to 42 ng/cm2 at the lower trunk and 9 to 47 ng/cm2 at the upper trunk. Crown length and distance from crown base had significant positive and negative effects on IAA amounts in the trunk of sugi cultivars, respectively. Distance from crown base had a larger effect on IAA amounts than crown length. In Yaichi, taller trees had larger IAA amounts at both the lower and upper trunk. 相似文献
92.
93.
Hongyan Han Sayaka Yamanaka Takamitsu Tsukahara Yoshio Hotta Tokuji Takagi Hajime Kumagai 《Animal Science Journal》2021,92(1):e13651
Gum arabic (GA) has potential rumen modifier functions. This is the first study to investigate the in vitro ruminal fermentation characteristics of GA. Rumen fluid was collected from ruminal fistulated wethers; rolled barley and ryegrass straw were used as substrates for concentrate and forage conditions, respectively. Besides incubating with the substrates alone (control), GA or potato starch (PS) was added at 0.2%, 1.0%, and 2.0% along with substrates. Under the concentrate substrate condition, GA treatments showed higher total gas production in 24-h incubation, but lower methane production in 24- and 48-h incubation compared with PS treatments (p < 0.05). The 1.0% and 2.0% GA and 0.2% and 1.0% PS treatments showed higher dry matter and neutral detergent fiber digestibility and lower NH3-N, and higher short chain fatty acid concentrations compared with the control at 24-h incubation (p < 0.05). The GA treatments also showed a lower acetate/propionate ratio than PS treatments at 48-h incubation (p < 0.01). Under the forage substrate condition, the treatment effects were not significant, except for a higher proportion of propionate with GA than with PS at 24 and 48 h of incubations. We thus concluded that GA supplement may exert potential rumen modifier effects particularly under concentrate feeding condition. 相似文献
94.
Ishikawa H Shimoda M Yonekura A Mishima K Matsumoto K Osajima Y 《Journal of agricultural and food chemistry》2000,48(10):4535-4539
The conformational changes in myoglobin, treated by microbubbling of supercritical carbon dioxide (SC-CO(2)), were investigated by measuring the circular dichroism spectra in the ultraviolet range and compared with those in other proteins (ovoalbumin, bovine serum albumin, and beta-lactoglobulin). Irreversible unfoldings were observed after the microbubbling of SC-CO(2) at 35 degrees C and 30 MPa for 30 min. The degree of unfolding depended on the number of intramolecular S-S bonds. alpha-Helix contents of myoglobin decreased with increasing density of SC-CO(2). Unfoldings of myoglobin induced by heating, pH-lowering, and the addition of a denaturant were reversible. The irreversible unfolding of myoglobin was also observed by the bubbling of gaseous CO(2) under atmospheric pressure, but heating was required. 相似文献
95.
J E Roybal R K Munns W J Morris J A Hurlbut W Shimoda 《Journal of the Association of Official Analytical Chemists》1988,71(2):263-271
A sensitive method is described for the determination and confirmation of zeranol and zearalenone, as well as their isomers and metabolites, in edible animal tissue. The analytes are extracted from tissue with methanol, hydrolyzed enzymatically, cleaned up by acid-base partitioning, determined by liquid chromatography (LC) with electrochemical (EC) detection, and confirmed by gas chromatography/mass spectrometry (GC/MS). LC analysis is performed by isocratic elution with a buffered mobile phase using a Nova-Pak reverse-phase C18 column with amperometric EC detection at +0.90 V. Capillary GC/MS analysis of the trimethylsilyl derivatives provides mass spectral confirmations. 相似文献
96.
Masuda T Inaba Y Maekawa T Takeda Y Yamaguchi H Nakamoto K Kuninaga H Nishizato S Nonaka A 《Journal of agricultural and food chemistry》2003,51(7):1831-1838
A simple detection method for a powerful radical scavenging compound in a mixture containing a large variety of compounds, such as the raw extract of edible plants, was developed using 1,1-diphenyl-2-picrylhydrazyl (DPPH) as the radical reagent. The method was established on the basis of the features of the typical chain-breaking antioxidation reaction mechanism, which suggests that the radical scavenging antioxidant should be converted to other stable nonradical compounds during the reaction. This method requires only a simple HPLC instrument, and the disappearance or decrease in the peak intensity, which is induced by the addition of DPPH. This change is monitored by the HPLC to detect the powerful radical scavenger from the complex mixture. The method was applied to the detection and identification of the most powerful antiradical compound in the extracts of three antioxidatively active plant extracts (Psidium guajava, Citrus depressa, and Hypericum chinense). The radical scavenging efficiency of a newly identified compound from H. chinense was also compared with that of Trolox and catechin using the method. 相似文献
97.
Liquid chromatographic determination of chlortetracycline hydrochloride in ruminant and poultry/swine feeds. 总被引:1,自引:0,他引:1
D C Holland K C Faul J E Roybal R K Munns W Shimoda 《Journal of the Association of Official Analytical Chemists》1991,74(5):780-784
A liquid chromatographic (LC) method is described for the determination of chlortetracycline hydrochloride (CTC) in poultry/swine and ruminant feeds in the 10-100 ppm range and in premix. CTC is extracted from ground feed/premix with acidified acetone, and the extract is filtered through a Millex-HV filter or disposable C18 column. The filtrate is partitioned with methylene chloride when additional cleanup is necessary. A Nova-Pak C18 column is used for LC separation with determination at 370 nm. The average recovery of CTC from premix was 95% with a standard deviation (SD) of 1.70 and a coefficient of variation (CV) of 1.79%. The overall average recovery from feeds was 77% with an SD of 3.18 and a CV of 4.10%. 相似文献
98.
Yoshio Yoshida 《Euphytica》1962,11(1):95-111
Radiation breeding for the introduction of additional desirable characters into improved varieties in autogamous plants, especially in cereals, would be much more feasible if more efficient screening methods could be found. Such methods are proposed in this report. From the standpoint of the theory of probability, it is intended to establish effective screening methods by which a desirable X2 mutant can be detected in a minimum total of X2-plants, and/or X1- and X2-plants in the aggregate.The relative efficiencies of four new methods and the standard method are compared, the improved ear-to-row method (method B), the one-plant-one-grain method (method C), the one-plant-two-grain method (method D) and one-plant-three-grain method (method E) all of which are more effective than the conventional ear-to-row method (method A). In method B, the total number of X2-plants required to recover at least one desirable X2-plant is obtained when the probability of detecting at least one X2-line with one or more desirable mutants among X2-lines is equal to the probability of detecting at least one desirable mutant among plants in that X2-line. In methods C, D and E, one, two or three grains respectively, taken from each of the X1-plants of the number required to detect at least one desirable X2-plant, are sown to obtain corresponding X2-plants.The number of X1-plants, total X2-plants, and X1- and X2-plants in the aggregate required to obtain at least one desirable mutant (m, mn and m+mn respectively) shows the following relations: method C>D>A>E>B for m, ABED>D>C for mn and ABC>D>E (the last two being very close to each other) for m+mn.Each of the new methods B, C, D and E will be applicable in radiation breeding. When the discrimination of a mutant is difficult method B will be useful. On the contrary, when a mutant is easily distinguishable, method C, with dense planting in X1, will frequently be much better. In some cases methods D and E, especially D, will be more useful in the practice of radiation breeding than method C. Method A should not be used in any case. 相似文献
99.
利用介电特性对食品加工过程进行非破坏性检测技术的研究 总被引:1,自引:0,他引:1
选用标准蔗糖和新鲜胡萝卜、葱为材料,研究干燥过程中原料电物性及水分含量变化规律的相关性。结果表明,60℃温度下热风干燥几种新鲜蔬菜,其水分含量随着干燥时间的增加而下降,电容值的变化趋势与水分的变化相同,两者存在极显著的线性相关性。水分的变化规律可以用相对应点的电容的变化来说明,从而对干燥终点的非破坏性及连续性检测和控制成为可能。 相似文献
100.
The Wx
b gene, one of the alleles at the rice waxy(wx) locus, is activated at cool temperatures during seed development, andas a result, a large amount of amylose is accumulated causing a reductionin rice grain quality. We found that the seeds of a du mutant couldbe visibly distinguished depending on whether they matured at cool ornormal temperatures. Using these characteristics, we isolated a mutantcandidate insensitive to cool temperatures. While the amylose content inthe original line was about 2% at a normal temperature (28 °C)and 12% at a cool temperature (21 °C), in the mutant candidate(coi) the amylose content was not affected by temperatures, i.e. theamylose content was about 3% at both temperatures. This finding incombination with the results of an immunoblot analysis indicated that theabsence of an increase in the amylose content in this mutant was caused bya constant level of Wx gene expression at normal and cooltemperature. Genetic analysis revealed that this insensitivity to cooltemperatures was caused by a single recessive mutation. This mutantshould be useful in breeding programs designed to produce rice of desiredquality at cool temperatures and in understanding genetic and molecularmechanisms that respond to slight changes in temperature. 相似文献