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1.
Twelve hundred and twenty-eight goats (Capra hircus L.) from a sub-tropical and humid zone of India were examined for gastrointestinal nematodes. The species encountered in the region were: Haemonchus contortus, Bunostomum trigonocephalum, Oesophagostomum columbianum, Trichuris globulosa, O. aspersum, and T. ovis. The overall infection rate was 86.8%. Among various species found, H. contortus emerged as the most prevalent, although B. trigonocephalum and O. columbianum were also significantly in evidence. The seasonal fluctuation in infection was assessed by monitoring the faecal egg count of 1638 goats slaughtered during the 1-year period. The maximum values for the prevalence and overall mean eggs g-1 of faeces (EPG) were observed after the heavy rainfall season and remained at a relatively high level from July to December. H. contortus and O. columbianum appear to be of major importance as parasites in the goats of this climatic zone; the role of climatic factors in their prevalence is discussed.  相似文献   
2.
本文分析了印度Leh地区沙棘籽油中脂肪酸各成分的含量,结果显示沙棘种子含油量为17.61%,籽油富含油酸(23.012%)和亚油酸(30.162%).  相似文献   
3.
目前印度已经认识到硫在植物营养中的实际意义.之所以有这样的认识,是因为越来越多的报道表明了在印度许多地区出现了缺硫现象,而且,研究者们也证实了40多种作物施硫后的显著增产效应.据估计印度大约有30%的农田作物可能正在遭受不同程度的缺硫危害.从当前情况看,作物(包括淋洗)每年从土壤中移走的S大约有110万公吨,而通过施肥加入的S却只有68万公吨.因此,多年来印度农业中的S是不平衡的,而且这种情况还将继续下去.这就是说,土壤中的S还在继续被消耗.近年来,通过国内外共同努力,硫的研究已有发展.与此同时,有关研究的实用价值也日益引起了重视并广为传播,因而农民们通过包括S在内的施肥实践已向挖潜增产上前进了一大步.S在四个大量元素(N、P、K和S)中是最便宜的一个,而施硫的经济效益又十分诱人.故本文着重对印度农业S研究和应用等诸方面的问题进行了讨论.  相似文献   
4.
Eight maize complexes and varieties representing high and low yield levels were tested for their suitability as top cross testers by comparing the performance of the crosses in relation to the combining ability of the parents estimated by diallel analysis. The discriminating ability of the testers was compared by Schumann and Bradley test. In both cases the results clearly showed that the low performing testers were better and more reliable than the high performing complexes. The utility of per se performance as an indication of general combining ability of the complexes has been discussed.  相似文献   
5.
本文用气相色谱仪分析了印度Leh地区沙棘叶油中种脂肪酸的含量,结果显示:该地区沙棘叶油中富含硬脂酸,其值可以达到13.853%,山嵛酸13.938%,亚油酸7.579%,掬焦油酸6.638%,十八稀酸4.622%。  相似文献   
6.
Indium concentrations have been determined by neutron activation in four members of each of the L3, L4, L5, and L6 chondritic meteorite classes. The range of concentrations is found to be from 0.14 to 22 parts per billion, with the highest values in L3 chondrites and the lowest values in the L5 and L6 classes. Plots of indium concentration versus relative mean deviation of pyroxene iron content, total carbon concentration, and primordial argon-36 concentration show positive correlations to varying degrees. Indium concentration appears to be a valuable parameter relating to variable formation conditions of the chondritic meteorites during the early history of the solar system.  相似文献   
7.
8.
Although it is assumed that fecal shedding of feline leukemia virus (FeLV) constitutes a transmission potential, no study has been performed showing that feces of infected cats can be a source of infection. In this study, we investigated fecal viral shedding of FeLV and its role in viral pathogenesis with the goal to improve infection control. FeLV RNA and DNA levels were determined in rectal swabs of experimentally infected cats by real-time PCR, and the results were correlated with proviral and viral loads in whole blood and plasma, respectively, and plasma p27 levels. All antigenemic cats shed FeLV RNA and DNA in feces. To determine whether the viral RNA detected was infectious, virus isolation from feces was also performed. Infectious virus was isolated from feces of antigenemic cats, and these results perfectly correlated with the isolation of virus from plasma. Na?ve cats exposed to these feces seroconverted, showing that infection through feces took place, but remained negative for the presence of FeLV provirus and p27 in blood, an outcome so far not described. Some of the organs collected after euthanasia were provirus positive at low copy numbers. From these results it is concluded that fecal shedding of FeLV plays a role in transmission, but it is probably of secondary importance in viral pathogenesis. Nevertheless, sharing of litter pans by susceptible and viremic cats could increase the environmental infectious pressure and appropriate measures should be taken to avoid unnecessary viral exposure.  相似文献   
9.
The COVID-19 pandemic is a major human health concern. The pathogen responsible for COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), invades its host through the interaction of its spike (S) protein with a host cell receptor, angiotensin-converting enzyme 2 (ACE2). In addition to ACE2, heparan sulfate (HS) on the surface of host cells also plays a significant role as a co-receptor. Our previous studies demonstrated that sulfated glycans, such as heparin and fucoidans, show anti-COVID-19 activities. In the current study, rhamnan sulfate (RS), a polysaccharide with a rhamnose backbone from a green seaweed, Monostroma nitidum, was evaluated for binding to the S-protein from SARS-CoV-2 and inhibition of viral infectivity in vitro. The structural characteristics of RS were investigated by determining its monosaccharide composition and performing two-dimensional nuclear magnetic resonance. RS inhibition of the interaction of heparin, a highly sulfated HS, with the SARS-CoV-2 spike protein (from wild type and different mutant variants) was studied using surface plasmon resonance (SPR). In competitive binding studies, the IC50 of RS against the S-protein receptor binding domain (RBD) binding to immobilized heparin was 1.6 ng/mL, which is much lower than the IC50 for heparin (~750 ng/mL). RS showed stronger inhibition than heparin on the S-protein RBD or pseudoviral particles binding to immobilized heparin. Finally, in an in vitro cell-based assay, RS showed strong antiviral activities against wild type SARS-CoV-2 and the delta variant.  相似文献   
10.
Bael [Aegle marmelos (L.) Correa], a medicinally important fruit tree grown on the Indian sub-continent, contains two bio-active furanocoumarins, marmelosin and psoralen, with pharmacological properties, plus two powerful groups of natural anti-oxidants, polyphenols and tannins. The present investigation aimed to measure the levels of these nutraceuticals at various stages of fruit development [150–345 days after fruit set (DAFS)] in two promising selections of bael from the Institute, CISH B-1 and CISH B-2, using a simple high performance liquid chromatography (HPLC) technique. Marmelosin and psoralen were extracted from 5 g of homogenised fruit mesocarp using benzene, while tannins were extracted as tannic acid with 80% (v/v) methanol in water. Polyphenol concentrations were measured spectrophotometrically at 760 nm using Folin-Ciocalteu reagent. The concentrations of marmelosin declined from 1,660 and 726 µg g?1 at 150 DAFS, to 523 and 170 µg g?1 at 345 DAFS in CISH B-1 and CISH B-2, respectively, whereas psoralen concentrations decreased from 216 and 41 µg g?1 to 102 and 9 µg g?1 during the same growth period in CISH B-1 and CISH B-2, respectively. Tannic acid concentrations decreased from 1.65 and 2.02 g 100 g?1 at 150 DAFS, to 1.52 and 1.54 g 100 g?1 at 345 DAFS in CISH B-1 and CISH B-2, respectively. The concentrations of total polyphenols did not show any significant changes in either bael selection over the same growth period. The concentrations of marmelosin and psoralen in CISH B-1 were highest in October (150 DAFS), while these values peaked in November (190 DAFS) in CISH B-2. The results suggest that fruit harvested at an early stage of growth (October–November) contained higher concentrations of nutraceuticals, increasing their suitability for fruit processing and use in the phyto-pharmaceutical industries.  相似文献   
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