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31.
Based on different surveys, dairy farmers are concerned about extensive use of exogenous oxytocin in buffaloes, which is being held responsible for reproductive problems including irregular oestrous cycle and delayed ovulation. For these concerns, effects of oxytocin injection on postpartum follicular dynamics, postpartum oestrous interval (PEI), oestrous length, the interval from onset of estrus to ovulation and blood progesterone (P4) were studied in Nili-Ravi buffaloes. For this purpose, 23 animals within 1 week after calving were randomly divided into three groups: without oxytocin (CON; n = 7), 10 i.u. oxytocin (LOW; n = 8), 30 i.u. oxytocin – (HIGH; n = 8) and used to record the PEI for the study period of 154 days. At subsequent estrus, three buffaloes from each group (not served) were selected randomly to monitor two cycles for 6 weeks. Transrectal ultrasonography was performed to evaluate follicular and corpus luteum (CL) development, and blood sampling was done for progesterone (P4) analysis. These results revealed that postpartum oestrous interval (PEI) decreased significantly in oxytocin-treated groups. The number of small, medium and total follicles on the left ovary was significantly higher in the HIGH group. However, an overall number of small and total follicles on both right and left ovaries was significantly higher in CON and HIGH groups. On the other hand, there was no difference in the number of follicles on the right ovary among all treatment groups. The same was true for the size of pre-ovulatory follicles, CL, P4 concentrations and oestrous cycle length. The intervals from onset of estrus to ovulation and from standing estrus to ovulation were increased considerably in the HIGH group. It is concluded that exogenous oxytocin administration resulted in the shortening of PEI but triggered a delay in ovulation. Moreover, a higher dose of oxytocin could stimulate the growth of small, medium, and total follicles in postpartum Nili-Ravi buffaloes.  相似文献   
32.
【目的】 研究苹果小吉丁Agrilus mali Matsumura自然种群在天山野苹果林的发生及其与影响因子之间的关系。【方法】 基于17块天山野苹果林标准地,以苹果小吉丁为研究对象,研究天山野苹果林生态系统中海拔、坡度、坡位、坡向等立地因子和林分郁闭度、林分密度、野苹果比例、树种丰富度等林分因子对苹果小吉丁种群影响效应等,构建预测模型。【结果】 海拔>1 400 m的林分内平均虫口数量最低,仅为0.49头/m样枝,1 250~1 299 m平均虫口数量最高,达到1.26头/m样枝。随着样地坡度的增加,苹果小吉丁种群数量逐渐降低,缓坡(6°≤坡度≤15°)林分的平均虫口数量最高,达到1.24头/m样枝,显著高于陡坡(26°≤坡度≤35°)的0.39头/m样枝(P<0.05)。林分郁闭度为0~0.29的林分虫口数量最高,达到1.44头/m样枝,显著高于郁闭度为0.30~0.49和0.50~0.79的林分(P<0.05)。林分密度<0.11的稀疏林分平均虫口数量最高,为1.5头/m样枝。海拔和坡度偏相关系数绝对值较大,分别为0.598和0.542,是苹果小吉丁虫口数量的关键影响因子,两者与平均虫口数量的关系达到显著水平(PX1=0.031;PX3=0.047;均小于0.05)。由海拔(X1)、坡度(X4)与苹果小吉丁虫口数量(Y)建立的多元回归模型为:Y=5.541-0.003X1-0.033X4。经F检验该线性回归预测模型达到显著水平(F=12.021,df=2,16,P=0.001)。将预测值与实测值进行比较,平均差异度为0.193;对实测值与预测值进行独立样本T检验,两者之间无显著差异。【结论】 海拔和坡度是影响苹果小吉丁种群数量的关键因子,其次为坡位,而林分郁闭度、林分密度、坡向、野苹果比例和树种丰富度对苹果小吉丁种群数量的影响作用稍弱,均为非主要因子。  相似文献   
33.
Cyadox (CYX) is a synthetic antibacterial agent of quinoxaline with much lower toxic effects. A safety criterion of CYX for clinical use was established by studying the pharmacokinetics and metabolism of CYX after oral (PO), intramuscular (IM), and intravenous (IV) administration. CYX was administered in six domesticated cats (three males and three females) by PO (40 mg/kg.b.w.), IM (10 mg/kg.b.w.), and IV (10 mg/kg.b.w.) routes in a crossover pattern. Highly sensitive liquid chromatography with ultraviolet detection (HPLC-UV) method was developed for detection of CYX and its metabolites present in plasma, urine, and feces. The bioavailability of CYX after PO and IM routes was 4.37% and 84.4%. The area under curves (AUC), mean resident time (MRT), and clearance (CL) of CYX and its metabolites revealed that CYX quickly metabolized into its metabolites. The total recovery of CYX and its main metabolites was >60% after each route. PO delivery suggesting first pass effect in cats that might make this route suitable for intestinal infection and IM injection could be better choice for systemic infections. Less ability of glucuronidation did not show any impact on CYX metabolism. The findings of present study provide detailed information for evaluation of CYX.  相似文献   
34.
Abstract

It is still unclear if different sources of nitrogen (N) can variably influence grain accumulation of zinc (Zn), N, and phytate. We tested foliar treatments of 0 or 0.25% Zn as zinc sulfate in combination with 0 or 1% N as ammonium chloride, ammonium sulfate or urea sprayed on field-grown-wheat (Triticum aestivum L.) foliage at anthesis and 10 days later. Leaf burning caused by ammonium chloride significantly decreased grain yield. Grain N concentration was the highest in the urea +0.25% Zn treatment. Foliar N application influenced grain Zn concentration only if Zn was included in the spray. Grain phytate concentration was significantly decreased by both N and Zn sprays. Estimated Zn bioavailability in grains was the highest at 0.25% Zn and was not influenced by the N sources. Based on grain yield, grain N concentration, and Zn bioavailability in grains, foliar application of Zn?+?urea is an optimal strategy.  相似文献   
35.
Biosynthesis of ascorbic acid in irradiated and unirradiated germinating rapeseed cultivars was studied at ambient room temperature (20–35 °C). Appreciable quantities of ascorbic acid (19.8–24.1 mg/100 g) were detected in the seeds and synthesis of this vitamin increased significantly (three fold) with increasing germination time depending upon rapeseed cultivars (p<0.05). Soaking of seeds in tap water (1:2) for 24 hours resulted in the decrease of the vitamin in each case. Among the radiation treatments (0.05–0.20 kGy), maximum amounts of ascorbic acid were found in 0.10 kGy (342.1 mg/100 g dry weight) and 0.15 kGy (113.8 mg/100 g wet weight) samples after 96 hours of germination. An overall significant linear relation (r=0.96) was observed between vitamin biosynthesis and germination time upto 96 hours in rapeseed.  相似文献   
36.
春尺蠖羽化期监测及其无公害防治试验   总被引:2,自引:0,他引:2  
[目的]通过对新疆阿克苏市春尺蠖羽化期的动态监测,旨在掌握春尺蠖的最佳防治时期;春尺蠖的无公害防治试验,为春尺蠖高效无公害防治技术在阿克苏地区的推广应用提供参考.[方法]成虫期利用光控杀虫灯、糖醋液、树干涂胶来进行动态监测;成虫期采取树干直接涂胶、间接涂胶来进行防治;幼虫期采取两种生物制剂来进行防治.[结果]阿克苏市春尺蠖的羽化期在3月5~27日.雄虫的羽化期比雌虫的羽化期要早3~5 d.无公害防治试验结果表明:树干直接涂胶比间接涂胶的捕获数量高出6.8倍;从幼虫虫口密度减退率来看,树干间接涂胶后的幼虫虫口密度比树干直接涂胶后的幼虫虫口密度高出2.2倍;两种生物制剂以核型多角体病毒的效果最好,其防治效果达到90.74;.[结论]春尺蠖的最佳防治时期应在3月5日之前,利用雌、雄虫不同的羽化期分而治之.羽化期的监测使用控杀虫灯的效果较好,发生量监测使用树干涂胶效果较好.无公害防治试验中树干直接涂胶和核型多角体病毒的效果好,且对果树、果品安全.  相似文献   
37.
Biodegradable polymers, such as poly(lactic acid) (PLA) have attracted a lot of attention in the scientific community recently due to a rapid growth of intensive interest in the global environment for alternatives to petroleum-based polymeric materials. Fatty nitrogen compounds (FNCs), fatty amides (FA), fatty hydroxamic acids (FHA), and carbonyl difatty amides (CDFA), which were synthesized from vegetable oils, were used as one of organic compounds to modify natural clay (sodium montmorillonite). The clay modification was carried out by stirring the clay particles in an aqueous solution of FA, FHA, and CDFA, by which the clay layer thickness increased from 1.23 to 2.61, 2.84 and 3.19 nm, respectively. The modified clay was then used in the preparation of the PLA/epoxidized soybean oil (ESO) blend nanocomposites. They were prepared by incorporating 2% of CDFA-MMT and 3% of both FA-MMT and FHA-MMT. The interaction of the modifier in the clay layer was characterized by X-ray diffraction (XRD), and Fourier transform infrared (FTIR). Elemental analysis was used to estimate the presence of FNCs in the clay. The nanocomposites were synthesized by solution casting of the modified clay and a PLA/ESO blend at the weight ratio of 80/20, which has the highest elongation at break. The XRD and transmission electron microscopy (TEM) results confirmed the production of nanocomposites. PLA/ESO modified clay nanocomposites show higher thermal stability and significant improvement of mechanical properties in comparison with those of the PLA/ESO blend. The novelty of this study is use of FNCs which reduces the dependence on petroleum-based surfactants.  相似文献   
38.
In a field experiment, various strengths of Hoagland’s nutrient solutions were sprayed to mitigate the deleterious effects of nutrient stresses at different growth stages on mash bean cultivars. Hoagland’s nutrient solution strengths of 0, 25, 50, and 75% were applied at 7, 14, and 21?days after emergence on mash bean cultivars namely Mash-2 and Mash-88. Hoagland’s nutrient solution of 75% strength markedly increased the growth and yield of mash bean cultivars if applied at 21?days after crop emergence. The Mash-88 showed superiority in terms of growth and yield traits as compared to Mash-2. The results suggested that growth and yield was not enhanced effectively by a low strength of Hoagland’s nutrient solution applied at initial growth stages. It is concluded that foliar-applied Hoagland’s nutrient solution of 75% strength can be used as an efficient tool when applied at appropriate growth stage (21?days after emergence) to get optimal yield.  相似文献   
39.
The production of oil from the conventional oilseed seed crops (viz. mustard, rapeseed) is not sufficient to meet the demands of Pakistani people. Due to this reason, a surplus quantity of oil is imported every year from different countries to fulfill the domestic demands of the cooking oil. This 2-year study was aimed to optimize the dose of NPK for profitable production of white mustard. Nitrogen (0, 60, 90?kg ha?1), phosphorous (0, 30, 60?kg ha?1) and potassium (0, 75, 100?kg ha?1) were applied in various combinations. The results indicated that highest seed yield and profitability was recorded with NPK at 90–60–100?kg ha?1, which was attributed to improvement in crop growth. In crux, application of NPK at pre-optimized rate might be a viable option to improve the growth, yield, oil quality, and economics of white mustard production under arid climates in Pakistan. According to the results, a balanced use of NPK fertilization is a key management strategy for white mustard growing farmers of arid region.  相似文献   
40.
The role of trypsin in plaque production by simian rotavirus SA-11 monolayers of MA-104 cells are investigated. Initial trypsin treatment of the virus alone or its presence only during the early phases of virus-cell interaction was found to be insufficient for plaque production by the virus. Presence of trypsin (5 microgram/mL) in the agar overlay throughout the five day incubation period was essential for the optimal development of the virus plaques. Production of plaques by the incorporation of trypsin in the overlay was not due to the enzymatic degradation of any plaque-inhibitors in the agar used. Experiments using high (4 PFU/cell) and low (35 PFU/10(6) cells) multiplicities of infection suggest that trypsin added to fluid maintenance medium facilitates the cell-to-cell spread of progeny virus particles. Therefore, the enzyme incorporated in the agar overlay appears to play a similar role thereby assisting in the formation of SA-11 plaques.  相似文献   
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