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排序方式: 共有195条查询结果,搜索用时 31 毫秒
171.
172.
Riad H Khalil Amany M Diab Medhat S Shakweer Hanan A Ghetas Mohammed M Khallaf Amira AE‐D Omar 《Aquaculture Research》2018,49(7):2357-2365
This work was carried out to investigate the effects of injection of Tenacibaculum maritimum formalin‐killed cells (FKC), extracellular products (ECPs) and crude lipopolysaccharide (LPS) as well as 1% feed supplements of oil extracts of Echinacea purpurea and Origanum vulgare on sea bass immunity improvement to the favour of T. maritimum experimental infection control after 4 weeks of the experiment. Tenacibaculum maritimum isolated from naturally infected sea bass showed brown to yellowish‐brown lesions (sores) on gills, skin and/or fins and identified by different biochemical methods and polymerase chain reaction technique. Immune parameters namely, total protein, globulin and lysozyme activity, as well as the relative level of protection were improved by T. maritimum (FKC), (LPS), (ECPs), O. vulgare and E. purpurea, respectively compared with control. Histopathological examination of T. maritimum naturally infected sea bass indicated many pathological changes in gill, skin and musculatures. Present study could be concluded that application of T. maritimum (FKC), (LPS), (ECPs), O. vulgare or E. purpurea improved sea bass immunity to the favour of disease resistance against T. maritimum. Further investigations on the combination between the previous control methods and the vaccine application methods will be needed. 相似文献
173.
Yee JL Walker J Khalil H Jiménez-Flores R 《Journal of agricultural and food chemistry》2008,56(13):5153-5157
Supercritical fluid extraction (SFE) has been utilized by the food industry in many applications to extract, fractionate, and recover compounds from various food matrices. However, little research has been conducted using SFE as an alternative process for producing reduced-fat cheese. Lipids in cheeses may be selectively extracted due to the nonpolar properties of supercritical carbon dioxide (SC-CO2), without leaving residual chemicals as is the case in solvent extraction. The objective of this study was to evaluate the influence on the extraction process due to cheese variety and protein breakdown by age. A Latin square design was utilized to test the extractability of lipids from Parmesan and Cheddar cheeses, aged young (9-10 months) or old (24 months). Extraction took place in a 500 mL SFE vessel using 100 g of grated cheese samples. The SFE parameters of the extraction were 350 bar, 35 degrees C, and supercritical carbon dioxide at a flow rate of 20 g/min for 55 min. Compositional analysis measured all treated samples and controls of total lipids, lipid profiling, total protein, protein/peptide analysis, moisture, ash, and pH. Cheese type was a major variable in fat extraction. The extraction in Cheddar showed an average fat reduction of 53.56% for young cheese, whereas that in old Cheddar was 47.90%. However, young Parmesan was reduced an average of 55.07%, but old Parmesan was reduced at 68.11%, measured on a dry basis. SFE extracted triglycerides and cholesterol, but did not remove phospholipids. This investigation introduces the observations of the effect of Cheddar and Parmesan varieties on SFE, offering data on the important parameters to consider in the design of SFE processes to reduce fat in cheese. 相似文献
174.
Strategies of presenting instructional information affect the type of cognitive load imposed on the learner's working memory. Effective instruction reduces extraneous (ineffective) cognitive load and promotes germane (effective) cognitive load. Eighty first-year students from two veterinary schools completed a two-section questionnaire that evaluated their perspectives on the educational value of a computer-based instructional program. They compared the difference between cognitive loads imposed by paper-based and computer-based instructional strategies used to teach the anatomy of the canine skeleton. Section I included 17 closed-ended items, rated on a five-point Likert scale, that assessed the use of graphics, content, and the learning process. Section II included a nine-point mental effort rating scale to measure the level of difficulty of instruction; students were asked to indicate the amount of mental effort invested in the learning task using both paper-based and computer-based presentation formats. The closed-ended data were expressed as means and standard deviations. A paired t test with an alpha level of 0.05 was used to determine the overall mean difference between the two presentation formats. Students positively evaluated their experience with the computer-based instructional program with a mean score of 4.69 (SD=0.53) for use of graphics, 4.70 (SD=0.56) for instructional content, and 4.45 (SD=0.67) for the learning process. The mean difference of mental effort (1.50) between the two presentation formats was significant, t=8.26, p≤.0001, df=76, for two-tailed distribution. Consistent with cognitive load theory, innovative computer-based instructional strategies decrease extraneous cognitive load compared with traditional paper-based instructional strategies. 相似文献
175.
The purpose of this article is to present the diseases induced in humans and animals by the different species of Chlamydophila, after providing an overview on the history of these infectious agents and their taxonomy. The route of transmission and the available methods for prevention and control in the different animal species are reviewed. 相似文献
176.
Katsunori Tachihara Mohammad Khalil El-Zibdeh Atsushi Ishimatsu Masatomo Tagawa 《Journal of the World Aquaculture Society》1997,28(1):34-44
Survival of the seed of goldstriped amberjack Seriola lalandi was consistently enhanced by intramuscular injection of triiodothyronine (T3 ) to the broodstock fish at a dose of 20 mg/kg body weight. Survival rates at the time of transfer to net cages (35 d after hatching) were 2.6–5.0% for the T3 treatment while only 0.3–2.1% for the control. Survival rates 36 mo after hatching was estimated to be 12 times higher in the T3 -treated group (1.1%) than in the control (0.09%). T3 concentration in newly spawned eggs increased from control levels of 0.3–1.0 ng/g to 68–127 ng/g 2 d after injection and subsided with successive spawns. T3 concentration in the treated larvae was about 360 times higher than in the control upon hatching (29 np/p vs 0.08 ng/g), but became indistinguishable from the control 6 d after hatching. These results indicate injection of T3 to the broodstock of S. lalndi to be of practical value in aquaculture of the species. 相似文献
177.
Cowpea plants ( Vigna sinensis Savi.) were grown in pots for two successive years. These plants were daily maintained water holding capacities (15, 25, 45, 65 %).
The foliage of plants grown at every level of soil moisture was sprayed till dripping with kinetin solutions (0, 10, 20, 40 mg/1) three times after, 3, 6 and 9 weeks from sowing. Samples were taken at the two physiological stages before flowering and during flowering for growth measurements and determination of nitrogen fractions.
Water shortage led to retardation of stem length, number of internodes, number of leaves and dry weight of shoots. Kinetin reduced stem length of cowpea shoots. On the other hand, it exhibited stimulative effect when applied at concentrations 10 and 20 mg/1 on number of internodes, and dry weight of shoots.
Water stress decreased total–N and protein–N contents of cowpea shoots. On the other hand total soluble–N content was increased under the same conditions. Kinetin increased total–N and protein–N contents of cowpea shoots. Meanwhile, the same growth regulator decreased total soluble–N when applied at 45 %, 25 % and 15 % W.H.C. levels. 相似文献
The foliage of plants grown at every level of soil moisture was sprayed till dripping with kinetin solutions (0, 10, 20, 40 mg/1) three times after, 3, 6 and 9 weeks from sowing. Samples were taken at the two physiological stages before flowering and during flowering for growth measurements and determination of nitrogen fractions.
Water shortage led to retardation of stem length, number of internodes, number of leaves and dry weight of shoots. Kinetin reduced stem length of cowpea shoots. On the other hand, it exhibited stimulative effect when applied at concentrations 10 and 20 mg/1 on number of internodes, and dry weight of shoots.
Water stress decreased total–N and protein–N contents of cowpea shoots. On the other hand total soluble–N content was increased under the same conditions. Kinetin increased total–N and protein–N contents of cowpea shoots. Meanwhile, the same growth regulator decreased total soluble–N when applied at 45 %, 25 % and 15 % W.H.C. levels. 相似文献
178.
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180.
Ramadan G. Sary Ragab H. Mohamed Karim M. Khalil Al-Lethie A. Al-lethie Hassan A. Hussein 《Reproduction in domestic animals》2020,55(3):343-350
The current study aimed to investigate the effect of testicular artery angioarchitecture on the spermiogram parameters in Egyptian Buffalo bulls. Eight adult buffalo bulls aged between 2 and 8 years were used for semen evaluation. For anatomical studies, the masculine gonads were collected after slaughtering 30 adult bulls and prepared for injection by different masses (Urographine®, Latex and Epoxy) through the testicular artery. The mass activity of the ejaculate was assessed immediately after collection. The sperm motility in fresh bull ejaculate was more than 80%. The overall mean percentage of sperm abnormalities was <18%. The recorded sperm abnormalities were mostly secondary one including distal protoplasmic droplet, fragmented tail, detached head, detached galea capitis and bent tail. The highest percentage of sperm viability was recorded just after sperm collection (alive > 85%). The results revealed that testicular artery can be divided into three parts (abdominal, funicular and marginal parts) along its course. The coils of the funicular part forming a cone-like structure with its base fixed to the head of the testis. Two epididymal branches to the head and tail of epididymis emanate from the funicular part which continues as pars marginalis on the lateral surface of testis before its division into the lateral and medial testicular arteries on approaching the tail extremity of the testis. The increase in the length of the testicular artery with increase in the size of the testes played a great role in the degree of complexity of the architectural vascular patterns. The degree of complexity is affected by the number of coils formed by the vessel. The increase in the convolutions of the vessel will reduce the speed of blood flow to the gonads. Thus in turn will enabling the thermoregulatory mechanism to work more efficiently and will affect the semen value. 相似文献