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51.
Viral isolation, polymerase chain reaction (PCR), dot blot hybridization (DBH), and indirect enzyme-linked immunosorbent assay (iELISA) were used for the diagnosis of lumpy skin disease in clinically infected, fevered, and apparently normal dairy cows. Lumpy skin disease virus (LSDV) was isolated from skin biopsies and blood samples collected from clinically infected cows in percentages of 72% and 20%, respectively. The virus recovered from blood samples collected from fevered cows in percentage of 33.3%. Both PCR and DBH detected viral DNA in 100% of skin biopsies collected from clinically infected cows whereas the detection rates in blood samples collected from clinically infected animals were 100% and 84% using PCR and DBH, respectively. Viral DNA was detected in blood samples collected from fevered cows using PCR and DBH in percentages of 77.8% and 66.6%, respectively. Only 19.1% of blood samples collected from in-contact cows was positive for both of PCR and DBH. Detection rates of antibodies against LSDV using iELISA in serum samples collected from clinically infected and fevered cows were 56% and 11.1%, respectively, whereas all in-contact cows had no antibodies against the virus.  相似文献   
52.

Background:

Molecular diversity of Leishmania major and its morphological changes have become a controversial issue among researchers. Some aspects of polymorphic shapes of amastigotes in clinical manifestations along with molecular variation were evaluated among suspected patients of some exceptional zoonotic cutaneous leishmaniasis locations in Northern Khuzestan, Southwestern Iran.

Methods:

Suspected patients (n = 165) were sampled in zoonotic cutaneous leishmaniasis foci over two consecutive years during 2012-2014. Prepared smears were stained, scaled and measured by ocular micrometer. DNA was extracted from smears; ITS-rDNA and Cytochrome b (Cyt b) markers were amplified, and PCR products were digested by BsuR1 restriction enzyme. Then the RFLP and sequencing were employed.

Results:

Only L. major was identified in patients containing regular amastigotes'' shapes (oval or round) with a size of 2-4 µm in each of classical wet, dry, mixed lesions. Meanwhile, irregular shapes (spindle, pear, or cigarette) were observed separately in non-classical wet lesions with more than 4 µm. Interestingly, a few amastigotes with an external flagellum were observed in some lesions. All sequenced ITS-rDNA and Cyt b genes of L. major did not show any molecular variation (χ 2 P > 0.05), including only one common haplotype (GenBank access no. EF413075).

Conclusion:

Findings proved that unlike other endemic foci, there is not a meaningful correlation between phenotypic and genotypic features of L. major isolates. This study is considered as the first comprehensive report to incriminate morphometric shapes of L. major amastigotes, which enhances our knowledge concerning their relevance with various clinical appearances and genotypic traits. Key Words: Leishmania major, Nuclear gene, Mitochondrial gene, Amastigote shapes, Iran  相似文献   
53.
Background: Thiamine (VitB1) is a vitamin with various important physiological functions and postulated therapeutic effects. Its use as an analgesic in neuropathic pain has been undergoing in clinical settings. However, there has been little experimental investigation on this effect. In this study, anti-nociceptive and anti-inflammatory effects of thiamine were investigated in mice. Methods: Three doses of thiamine (50, 100 and 125 mg/kg) were used by intraperitoneal injection in this study. Acute and chronic anti-nociceptive effects were examined using hot plate test alone and after sciatic nerve ligation, respectively. Imipramine (40 mg/kg) was used as positive control. Anti-inflammatory effects of thiamine on acute and chronic inflammation were assessed using xylene-induced edema in ears and granuloma caused by compressed cotton implantation, respectively. Sodium diclofenac (15 mg/kg) was used as positive control. Open field test was performed to differentiate the mice responses in the acute anti-nociceptive tests. Results: All three doses of thiamine showed significant analgesic effects in non-ligated mice and also in neuropathic pain in ligated animals. Increasing the dose of thiamine correlated with a more pronounced and sustained effect. Acute anti-inflammatory investigation showed that thiamine injected 30 or 60 minutes before xylene application reduced the weight of edematic ears. However, the effect of thiamine was less pronounced than diclofenac. Furthermore, when injected once daily for 7 days, all doses of thiamine significantly reduced the weight of the cotton disks, showing suppression of granuloma formation. Conclusion: Taken together, it has been shown that thiamine possesses remarkable analgesic activities and also has significant anti-inflammatory effects, confirming its clinical use in controlling pain and less in inflammation.  相似文献   
54.
番茄潜叶蛾Tuta absoluta (Meyrick)是危害茄科作物的重大入侵农业害虫,明确番茄潜叶蛾的田间危害特征及防虫网对番茄潜叶蛾成虫的防控作用,为防虫网在温棚的使用提供技术指导。利用防虫网+性诱剂的方法,分析番茄潜叶蛾的田间治理效果。采用田间观察和五点取样的方法,进行番茄潜叶蛾危害调查。在不同番茄品种的不同生育期监测到防虫网与对照处理的番茄潜叶蛾种群动态变化规律一致。苗期,‘德尔6’和‘粉帝F1’防虫网和对照处理的平均虫量分别为18.76、24.97只/板和75.92、87.71只/板(P>0.05);防虫网对两个品种的番茄潜叶蛾隔离率分别为39.10%和21.32%(P<0.05)。花期,‘鸿图’和‘粉帝F1’防虫网和对照处理的平均虫量分别为52.56、61.12只/板和53.85、64.05只/板(P>0.05);防虫网对两个品种的番茄潜叶蛾隔离率分别为22.95%和19.35%(P>0.05)。果期,‘德尔6’、‘鸿图’和‘粉帝F1’的防虫网和对照处理平均虫量分别为53.90、58.52只/板;47.52、65.79只/板和66.37、85.46只/板(P>0.05);防虫网对3个品种的番茄潜叶蛾隔离率分别为24.20%、28.93%和26.83%(P>0.05)。防虫网处理对3个生育期下的3个品种间的平均危害率均差异不显著(P>0.05),但防虫网处理的平均危害率均低于对照处理,差值达8.38%。二次多项式逐步回归分析结果表明番茄叶片或果实的平均危害率主要与潜叶蛾的早期虫口量相关。14目防虫网对番茄潜叶蛾具防控作用,隔离率最大为39.10%。  相似文献   
55.
The objective of the present study was to evaluate the potential effect of dietary calcium butyrate on growth performance, carcass traits and gut health in Japanese quails. In total, 320 one‐day‐old Japanese quails were randomly assigned to 4 equal treatments, with 8 replicates of 10 Japanese quails, for 4 weeks. The Japanese quails in control treatment were fed control diet whereas in the other treatments the Japanese quails were fed diet supplemented with calcium butyrate at 0.3, 0.5 and 0.7 g/kg diet. Data concerning performance measurements were recorded weekly. In addition, eight Japanese quails (one/replicate) from each treatment were selected randomly for serum collection to measure pro‐ and anti‐inflammatory cytokines. Pooled faecal samples from each replicate of each treatment were also collected at three time points (0, 2 and 4 weeks) for count E. coli and C. perfringens. The results showed that after 7 days of the experimental period, Japanese quails fed calcium butyrate supplemented diet at 0.7 g/kg showed a greater (p < .05) body weight and a favourable (p < .05) feed conversion ratio than the other treatments. Moreover, serum superoxide dismutase and catalase activities were increased (p < .05) in Japanese quails fed calcium butyrate supplemented diet at 0.7 g/kg. Calcium butyrate supplementation at 0.7 g/kg was associated with reduction (p < .05) in TNF‐α, IL‐6 and IL1‐β, while IL‐10 was increased (p < .05). In addition, after 2 weeks of calcium butyrate supplementation, a reduction (p < .05) in E. coli and C. perfringens counts was observed in excreta of Japanese quails fed 0.5 and 0.7 g calcium butyrate/kg diets. It is concluded that calcium butyrate supplementation improves body weight gain, reduces E. coli and C. perfringens counts and has anti‐inflammatory/anti‐oxidant effect in Japanese quails.  相似文献   
56.
Anesthetics are commonly used in the aquaculture industry to reduce stress and prevent mortality of fish during transportation, handling, and surgical procedures. This study assessed the efficacy of four anesthetic agents (clove oil, propofol, 2‐phenoxyethanol [2‐PE], and ketamine hydrochloride) on Persian sturgeon, Acipenser persicus, juveniles. In addition, results of the first experiment were used to evaluate sedation concentrations suitable for transportation of Persian sturgeon. The concentrations of anesthetics or sedatives evaluated in the first experiment were: 25, 50, 75, and 100 mg/L for clove oil; 1, 1.25, 2.5, and 5 mg/L for propofol; 110, 330, 550, and 770 mg/L for 2‐PE; and 1250, 2500, 3750, and 5000 mg/L for ketamine hydrochloride. Results show significant reduction in time to anesthesia and significant increase in recovery time with increase in concentration of all anesthetics. The most clinically useful concentrations of anesthetics tested were between 25 and 50 mg/L for clove oil, less than 1 mg/L for propofol, 330 mg/L for 2‐PE, and none of the tested concentrations for ketamine hydrochloride. In the second experiment, juveniles were placed in low concentrations of anesthetic solutions for 24 h and survival assessed. The four anesthetics tested are suitable for light sedation during transportation of A. persicus juveniles. Results are helpful to scientists working with Persian sturgeon aquaculture and restocking programs.  相似文献   
57.
In the current study, we tested whether the addition of a small amount of crystalline dl ‐methionine to a fishmeal‐based diet would affect general sulphur metabolism and apparent digestibility in Atlantic salmon (Salmo salar). Triplicate tanks of salmon with mean BW of half a kilo were fed a control diet or the control diet supplemented with 0.2 wt%dl ‐methionine (+17% methionine relative to control diet) for a period of 3 months. Feed intake and thus nutrient intake did not differ significantly between treatments. Fish fed the diet supplemented with dl ‐methionine had 18% higher mean intake of methionine. The apparent energy digestibility was significantly improved in the salmon fed the methionine‐enriched diet as was the methionine digestibility. Salmon fed the methionine‐supplemented diet had about 32% higher plasma‐free methionine concentration and 25% more total homocysteine 5 h post prandial. No difference was observed in hepatic‐free methionine, but hepatic cystathionine (~62%) and taurine (~20%) were significantly higher in fish fed the methionine‐enriched diet due to a higher transsulphuration. In the liver, taurine might be conjugated to bile acids (BAs), and conjugation of BAs increases their solubility and enhances their biliary secretion affecting the digestibility. Both faecal and plasma BA concentrations were elevated in fish fed the methionine‐enriched diet, although the differences did not reach statistical significance. Taken together, our data show that feeding salmon a fishmeal‐based diet supplemented with a small amount of crystalline dl ‐methionine increased the apparent energy digestibility, possibly through an increased liver transsulphuration and taurine production, which might enhance BA conjugation and biliary secretion.  相似文献   
58.
Genotypic variation in composition and antioxidant activity was evaluated using 25 cultivars, 5 each of white-flesh nectarines, yellow-flesh nectarines, white-flesh peaches, yellow-flesh peaches, and plums, at the ripe (ready-to-eat) stage. The ranges of total ascorbic acid (vitamin C) (in mg/100 g of fresh weight) were 5-14 (white-flesh nectarines), 6-8 (yellow-flesh nectarines), 6-9 (white-flesh peaches), 4-13 (yellow-flesh peaches), and 3-10 (plums). Total carotenoids concentrations (in microg/100 g of fresh weight) were 7-14 (white-flesh nectarines), 80-186 (yellow-flesh nectarines), 7-20 (white-flesh peaches), 71-210 (yellow-flesh peaches), and 70-260 (plums). Total phenolics (in mg/100 g of fresh weight) were 14-102 (white-flesh nectarines), 18-54 (yellow-flesh nectarines), 28-111 (white-flesh peaches), 21-61 (yellow-flesh peaches), and 42-109 (plums). The contributions of phenolic compounds to antioxidant activity were much greater than those of vitamin C and carotenoids. There was a strong correlation (0.93-0.96) between total phenolics and antioxidant activity of nectarines, peaches, and plums.  相似文献   
59.
Melatonin is known to protect sperm against freezing-inflicted damage in different domestic species. The aim of the study was to evaluate the effect of supplementation of semen extender with melatonin on the quality and DNA integrity of cooled and frozen/thawed rabbit spermatozoa. We also investigated whether the addition of melatonin to the semen extender could improve the fertility of rabbit does artificially inseminated with frozen/thawed semen. Semen samples collected from eight rabbit bucks were pooled and then diluted in INRA-82 supplemented either with (0.5, 1.0 or 1.5 mM) or without (0.0 mM) melatonin. Diluted semen was cooled at 5°C for 24 hr. For cryopreservation and based on the first experiment's best result, semen samples were diluted in INRA-82 in the presence or absence of 1.0 mM melatonin and then frozen in 0.25 ml straws. Following cooling or thawing, sperm quality and DNA integrity were evaluated. Furthermore, the fertility of frozen/thawed semen was investigated after artificial insemination. Supplementation of semen extender with 1.0 mM melatonin improved (p < .05) motility, viability, membrane and acrosome integrities in cooled semen compared with other groups. Sperm quality and DNA integrity were higher (p < .05) in frozen/thawed semen diluted in 1.0 mM melatonin-supplemented extender than in the control group. Conception and birth rates were higher in does inseminated with 1.0 mM melatonin treated semen compared with the controls. In conclusion, supplementation of semen extender with 1.0 mM melatonin improved the quality of cooled and frozen/thawed rabbit spermatozoa. Melatonin can preserve DNA integrity and enhance the fertility of frozen/thawed rabbit spermatozoa.  相似文献   
60.
In order to investigate the effects of exogenous spermidine on water limitation-induced damage on common bean (Phaseolus vulgaris L.) genotypes, a field experiment was conducted over two growth seasons. The experiment was arranged as a split-split plot design and three replications. Treatments were three water stress levels (non-stress, moderate and severe stress), three bean genotypes (Akhtar, Pak and COS12) and two spermidine levels (control and foliar application). The results showed that water stress reduced markedly leaf relative water content, SPAD values, specific leaf area, leaf area index, plant height, relative growth rate, shoot dry weight and grain yield; however, increased leaf density, leaf relative electrolyte leakage, stomatal density, leaf angle and leaf temperature of bean genotypes. Spermidine application increased relative water content, SPAD values, leaf area, leaf area index, shoot dry weight and grain yield. Overall, exogenous spermidine usage as a free radical scavenger counteracted deleterious water deficit effects.  相似文献   
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