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21.
To dye poly(lactic acid) (PLA) fiber with natural dyes has gained importance in recent years due to the production of the fully eco-friendly textile products. In this study, pure and modified PLA fibers with two different POSS nanoparticles, namely N-phenyl aminopropyl POSS (AP-POSS) and octa (aminophenyl) polyhedral oligomeric silsesquioxane (OAPPOSS), are dyed with three different natural dyes including alizarin, lawsone and indigo. The effects of the dyeing conditions including dyeing temperature and time, POSS nanoparticle concentration, natural dye types and concentrations are investigated on the dyeability properties of the PLA fiber samples. The wash and light fastness of the fiber samples are also investigated. According to the dyeability results, it is concluded that POSS nanoparticles are effective for increasing the dyeability of the PLA fiber with all natural dyes used in this study. As the added amount of the POSS nanoparticle increases, the dyeability of the PLA fiber increases. When the performances of the POSS nanoparticles are compared, it is seen that OAP-POSS is more effective than the AP-POSS nanoparticle.  相似文献   
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Background: Escherichia coli have recently been identified within the colonic mucosa of Boxer dogs with granulomatous colitis (GC). Eradication of invasive E. coli is associated with clinical and histological remission. Objectives: To determine antimicrobial susceptibility profiles of E. coli strains from GC and healthy dogs, and the association of antimicrobial resistance with clinical outcome. Animals: Fourteen Boxer dogs with GC and 17 healthy pet dogs. Methods: Prospective study: E. coli was cultured from GC biopsies and rectal mucosal swabs of healthy dogs. Individual strains were selected by phylogroup and overall genotype, determined by triplex‐ and random amplified polymorphic DNA‐polymerase chain reaction respectively. Antimicrobial susceptibility was determined by broth microdilution minimal inhibitory concentration. Results: Culture yielded 23 E. coli strains from GC (1–3/dog, median 2) and 34 strains from healthy (1–3/dog, median 2). E. coli phylogroups were similar (P= .18) in GC (5A, 7B1, 5B2, 6D) and healthy (2A, 10B1, 15B2, 7D). Resistance to ampicillin, amoxicillin‐clavulanate, cefoxitin, tetracycline, trimethoprim‐sulfa (TMS), ciprofloxacin, and chloramphenicol was greater (P < .05) in GC (21–64%) than healthy (0–24%). Enrofloxacin resistant E. coli were isolated from 6/14 GC versus 0/17 healthy (P= .004). Of the enrofloxacin resistant cases, 4/6 were also resistant to macrophage‐penetrating antimicrobials such as chloramphenicol, rifampicin, and TMS. Enrofloxacin treatment before definitive diagnosis was associated with antimicrobial resistance (P < .01) and poor clinical outcome (P < .01). Conclusions and Clinical Importance: Antimicrobial resistance is common among GC‐associated E. coli and impacts clinical response. Antimicrobial therapy should be guided by mucosal culture and antimicrobial susceptibility testing rather than empirical wisdom.  相似文献   
24.
This study aimed to examine the teat characteristics in relation to the animal temperament during milking in the Anatolian buffaloes using ultrasonographic, histomorphological and immunohistochemical methods. The teat canal length (TCL), teat wall thickness (TWT), teat cisternal diameter (TCD), teat diameter (TD), teat length (TL), and teat circumference (TC) values in docile (n = 5) and nervous (n = 7) buffaloes were measured at the 0th, 3rd and 6th minute of stimulation. In additional experiments, comparative histomorphology and immunohistochemical examinations of buffalo (n = 7) and cow teats (n = 8) were performed. It was determined that post-stimulation mean TCL values were significantly higher in nervous buffaloes than those of teats in docile buffaloes (< .05). A significant positive correlation between TCD and TD, TL and TC in both docile and nervous buffaloes was noted (< .05). Unlike nervous buffaloes where only 3/14 teat canals were open by 3rd minute of milking stimulation, almost all (9/10) teat canals were observed opened in docile buffaloes. There were fewer muscle but more collagen bundles in buffalo teats compared with cow teats. It seems that temperament of animal during milking effects the milking efficiency, and in nervous buffaloes, probably the stimulation alone may not be sufficient for opening of the teat canal and hence achieve complete milking.  相似文献   
25.
The majority of intramammary infections with Escherichia coli in dairy cows result in transient infections with duration of about 10 days or less, although more persistent infections (2 months or longer) have been identified. We apply a mathematical model to explore the role of an intracellular mammary epithelial cell reservoir in the dynamics of infection. We included biological knowledge of the bovine immune response and known characteristics of the bacterial population in both transient and persistent infections. The results indicate that varying the survival duration of the intracellular reservoir reproduces the data for both transient and persistent infections. Survival in an intracellular reservoir is the most likely mechanism that ensures persistence of E. coli infections in mammary glands. Knowledge of the pathogenesis of persistent infections is essential to develop preventive and treatment programmes for these important infections in dairy cows.  相似文献   
26.
Water temperature and system pressure effect on drip lateral properties   总被引:1,自引:1,他引:1  
A study was conducted at the department of Agricultural Structure and Irrigation, Harran University, Sanliurfa, Turkey, to determine the effect of increased irrigation water temperature at various irrigation system pressures on emitter flow rate, lateral elongation, and Standard Flow Rate Index for six different brands of drip laterals. Test materials consisted of seven pressure and seven non-pressure compensating irrigation laterals from different manufacturers. Tests results showed that (a) tensile resistance stress tests indicated that 25% elongation levels were reached at about 40 kg of load. On average, pressure compensating laterals reached 25% elongation at 38 kg, while non-pressure compensating laterals reached 25% elongation at 32-kg load. There was no clear indication of the tested brands’ lateral wall thickness on the measurement, (b) pressure-regulated drip emitters had no or limited flow rate change due to increased irrigation water temperature, whereas non-pressure compensating emitters had significantly (P < 0.05) increased flow rates, and (c) finally, increased irrigation water temperature resulted in decreased flow rate variations that had a positive effect on standard deviation. Standard uniformity values improved with decreased flow rate variations in drip emitter flow rates.  相似文献   
27.
A 2‐year study in the Central Anatolian Region of Turkey compared the performance of pasture‐fed suckling lambs and their dams, set‐stocked on grass‐legume pastures supplemented either with forage legumes or concentrate through a creep grazing/feeding system in a randomized block design. The treatments included continuous pasture grazing + creep grazing alfalfa; continuous pasture grazing + creep grazing birdsfoot trefoil; continuous pasture grazing + creep feeding concentrate (170 g kg?1 CP; 11.3 ME MJ kg?1 DM); and continuous grazing without creep feeding (control). In both years, creep feeding/grazing commenced in early June following a 42‐day pasture grazing period (period 1) and continued until mid‐summer for two separate periods of 21 days each (periods 2 and 3). Creep‐supplemented lambs grew faster (< .001) than those that grazed pasture alone, with no significant difference across all creep supplementation treatments. Across the years, the lambs grew at 223 and 161 g per head day?1 for creep‐supplemented and control groups respectively. None of the lamb feeding strategies affected the ewe liveweight gains (p > .05). Results from a bio‐economic optimization model, however, showed that supplementing the pasture with birdsfoot trefoil and alfalfa in periods 2 and 3, respectively, maximized economic returns with an extra profit of US$88.83 per lamb above those that grazed the pasture alone.  相似文献   
28.
以克服亚种间杂种不育来充分发掘亚种间杂种优势是提高水稻单产的一条有效途径。本研究,从一套以日本晴为背景,9311为供体的染色体片段代换系中鉴定出一个系T9424,其与日本晴配置的F1植株小穗与花粉育性较双亲显著降低,双亲间存在不亲和。重测序结果表明T9424在第1、第4和第5染色体上导入9311片段。日本晴/T9424 F2群体内单株基因型及育性鉴定结果表明,T9424与日本晴间杂种不育基因位于第5染色体上。利用F2群体内790株单株将该杂种不育基因定位于第5染色体分子标记PSM8与A14之间110kb的物理区段内。对日本晴/T9424 F1植株花粉与胚囊育性鉴定结果表明该杂种不育基因同时控制雌、雄配子败育,将该基因暂命名为S39(t)。相关结果有助于加深对水稻亚种间杂种不育现象的认识,为该基因克隆及其育种利用奠定基础。  相似文献   
29.
This study was designed to evaluate the effect of L-carnitine supplementation on the plasma malondialdehyde (MDA) and whole blood reduced glutathione (GSH) concentrations in experimentally-induced chronic aflatoxicosis in quails. For this purpose, a total of 80 quails up to 8 weeks old were divided into four equal groups. Group I served as control, Group II was given L-carnitine at the dose of 200 mg/litre in the drinking water for 60 days, Group III was given 60 microg total aflatoxin/kg diet for 60 days, and Group IV was given both 60 microg total aflatoxin/kg diet and 200 mg L-carnitine/litre in the drinking water for 60 days. Aflatoxin treatment caused a significant increase in plasma MDA and a significant decrease in blood GSH concentrations. On the other hand, there was a significant decrease in plasma MDA and a significant increase in whole blood GSH in the L-carnitine-supplemented group. The present study demonstrated that L-carnitine brought about the inhibition of lipid peroxidation by enhancing antioxidant capacity in quails with chronic aflatoxicosis.  相似文献   
30.
The efficiency of cronolone sponges in combination with either pregnant mare serum gonadotrophin (PMSG) or cloprostenol (PGF2alpha) for inducing and synchronizing the estrous cycle in Turkish Saanen does was investigated during the transition from non-breeding to breeding season. All does (n = 80) were treated with 20 mg cronolone sponges for 11 days and divided into 4 equal groups. In addition, each doe received an intramuscular injection of either 1.5 ml sterile saline solution, 0.075 mg PGF2alpha, 500 IU PMSG or 500 IU PMSG and 0.075 mg PGF2alpha, 24 h before the sponge removal. Cervical artificial insemination (AI) with frozen-thawed semen was performed once 16 h after the detection of the first accepted mount. The total estrous response for the first 24 +/- 4 h, total estrous response within 96 h, time to onset of the induced estrus, duration of the induced estrus and pregnancy rate was found to be 75.0%, 97.5%, 31.4 +/- 1.2 h, 29.3 +/- 1.2 h, and 33.3%, respectively. There were significant differences between the first two groups and the last two groups in terms of the onset of induced estrus and estrous response at the first 24 +/- 4 h (P < 0.05). These results indicate that the use of cronolone/PMSG was more effective than cronolone/PGF2alpha in the attainment of early and compact induction of estrus in Turkish Saanen does.  相似文献   
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