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91.
Stevia rebaudiana leaves are used as a zero-calorie natural sweetener in a variety of food products in Asian countries, especially in Japan. In this study, the hydroxycinnamate derivatives of S. rebaudiana have been investigated qualitatively and quantitatively by LC-MSn. Twenty-four hydroxycinnamic acid derivatives of quinic and shikimic acid were detected, and 19 of them were successfully characterized to regioisomeric levels; 23 are reported for the first time from this source. These comprise three monocaffeoylquinic acids (Mr 354), seven dicaffeoylquinic acids (Mr 516), one p-coumaroylquinic acid (Mr 338), one feruloylquinic acid (Mr 368), two caffeoyl-feruloylquinic acids (Mr 530), three caffeoylshikimic acids (Mr 336), and two tricaffeoylquinic acids (Mr 678). Cis isomers of di- and tricaffeoylquinic acids were observed as well. Three tricaffeoylquinic acids identified in stevia leaves are reported for the first time in nature. These phenolic compounds identified in stevia might affect the organoleptic properties and add additional beneficial health effects to stevia-based products.  相似文献   
92.
Wood-decay macro-fungi have been reported to be a major cause of decline of arid zone trees in the genera Acacia, Prosopis, Ziziphus and Azadirachta; the identity of these fungi, however, has not been confirmed in the state of Rajasthan in northwestern India. Direct sequencing of PCR amplified ITS regions of rDNA facilitated molecular identification of 26 isolates into species in eight genera (Ganoderma, Inonotus, Phellinus, Ceriporia, Schizophyllum, Phanerochaete, Pleurotus, Leucoagaricus) and one incompletely characterized Basidiomycota species. In addition to intra-specific phenotypic variations in basidiocarp morphology, Single Nucleotide Polymorphisms (SNPs) were recorded among isolates of P. pulmonarius, S. commune, G. lucidum and Ganoderma species. Both SNPs and insertions/deletions (INDELS) were recorded amongst Inonotus species. A phylogram based on multiple sequence alignment delineated all isolates into separate intra-specific subgroups along with their GenBank reference sequences with high bootstrap values. Phellinus repandus, L. meleagris, C. lacerata and three Inonotus species (I. rickii, I. patouillardii, and I. porrectus) reported herein are new fungal records from India.  相似文献   
93.
A total of 938 faecal samples (461 cattle calves, 264 buffalo calves, 55 lambs, 116 kids and 42 piglets) from different livestock farms and individual small holdings in six targeted states of India were collected and screened by modified Ziehl–Neelsen staining technique to determine the prevalence of Cryptosporidium spp. and its association with age, sex, season and faecal consistency in domesticated animals. Overall, 16.2 % of the animals were positive for Cryptosporidium infection with prevalence of 16.3, 24.2, 1.8, 3.5 and 19.1 % in cattle calves, buffalo calves, lambs, kids and piglets, respectively. The prevalence of infection was significantly higher (p?<?0.05) in bovines (19.3 % cattle and 33.7 % buffalo) below 1 month of age than in animals between 1 and 3 months of age. But in piglets, it was higher in the age group of 1 to 3 months (22.6 %) than in younger animals (9.1 %). Also, higher prevalence (p?>?0.05) was recorded in females than in males. Seasons had a significant effect (p?<?0.05) on the prevalence of infection in large ruminants, with the highest prevalence in monsoon (cattle 28.8 % and buffalo 36.6 %) followed by pre-monsoon and post-monsoon season. However, in case of sheep and goats, the prevalence was higher (p?>?0.05) in post-monsoon than in monsoon season. A high degree of association was noticed between Cryptosporidium infection and diarrhoea in ruminants screened during the present study. But, in case of pigs, the prevalence was higher in non-diarrhoeic than in diarrhoeic animals. Genotyping of Cryptosporidium spp. based on nested PCR amplification of partial 18S rRNA and its subsequent digestion with SspI, VspI and MboII restriction enzymes revealed prevalence of Cryptosporidium parvum in representative number of positive samples of cattle, buffalo and goats.  相似文献   
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95.
BACKGROUND: This study demonstrates the changes in six different pathophysiological parameters such as body weight, body temperature, fecal pellet count, blood-brain barrier (BBB) permeability, plasma corticosterone level and emergence of hemorrhagic peptic ulcer spots due to exposure to high environmental heat in three different age groups of freely moving rats. METHODS: Each age group of rats was sub divided into three groups: (i) acute heat stress-subjected to a single exposure for four hours in the Biological Oxygen Demand incubator at 38 degrees C; (ii) chronic heat stress-exposed for 21 days daily for one hour in the incubator at 38 degrees C, and (iii) handling control groups. The data were recorded for the analyses of the changes in different parameters just after the heat exposure from acute stressed rats and on 1st, 3rd, 6th, 9th, 12th, 15th, 18th and 21st day on chronic stressed rats for body temperature, body weight, fecal pellets count. For the analysis of changes in three other parameters, BBB permeability, plasma corticosterone level and peptic ulcer spots following chronic exposure to high environmental heat, data were recorded on 22nd day for the analysis. RESULTS: Analysis of variance (ANOVA-1) of the observations demonstrates a significant increase in body temperature, fecal pellet count, BBB permeability (except in adult group), plasma corticosterone level and emergence of hemorrhagic peptic ulcer spots in all three different age group of rats due to exposure to acute heat stress. However, chronic heat was found responsible for the significant reduction in body weight in weaning and young rats, increase in body temperature, number of fecal pellets excreted (in early days of chronic stress) and number of peptic ulcer spots in all three age groups of rats. At the same time, BBB extravasations were not observed in rats except very mild in weaning group. CONCLUSION: The results of the present study indicate that the acute as well as chronic exposure to hot environment significantly alters the physiology of different organs of the body.  相似文献   
96.
Pharmacokinetics, urinary excretion and plasma protein binding of danofloxacin was investigated in buffalo calves following intravenous administration at the dose rate of 1.25 mg/kg to select the optimal dosage regimen of danofloxacin. Drug concentrations in plasma and urine were measured by microbiological assaying. In vitro plasma protein binding was determined employing the equilibrium dialysis technique. The distribution and elimination of danofloxacin were rapid, as indicated by values (mean ±SD) of distribution half-life (t1/2α = 0.16 ± 0.07 h) and elimination half-life (t1/2β = 4.24 ± 1.78 h), respectively. Volume of distribution at steady state (Vss) = 3.98 ± 1.69 L/kg indicated large distribution of drug. The area under plasma drug concentration versus time curve (AUC) was 1.79 ± 0.28 μg/mlxh and MRT was 8.64 ± 0.61 h. Urinary excretion of danofloxacin was 23% within 48 h of its administration. Mean plasma protein binding was 36% at concentrations ranging from 0.0125 μg/ml to 1 μg/ml. On the basis of pharmacokinetic parameters obtained, it is concluded that the revision of danofloxacin dosage regimen in buffalo calves is needed because the current dosage schedule (1.25 mg/kg) is likely to promote resistance.  相似文献   
97.
98.
Abstract

Azotobacter chroococcum strains E12, HT57 were genetically tagged with lac Z, gfp to study the colonization behaviour on wheat (Triticum aestivum) and cotton (Gossypium sp.) in soil under controlled conditions. 103 – 104 cfu g?1 soil of HT57 lac Z were found to colonize roots of both cotton and wheat crops whereas 1.7 × 104 – 7.2 × 104 cfu g?1 soil of E12 gfp was colonizing wheat roots and 1.6 × 104 – 9.3 × 104 cfu g?1 soil of E12 gfp colonized cotton roots respectively. Tagged strains colonized mostly on root tips compared to basal roots in both the crops.  相似文献   
99.
Phytochemical investigation of the ethanolic extract of twigs of Kigelia pinnata DC. afforded one new iridoid 7-hydroxy eucommiol (1), and nine known compounds (2-10). The structure of compounds was elucidated by extensive spectroscopic methods, including 1D, 2D NMR experiments and MS analysis. All these compounds were evaluated for GLUT4 translocation modulatory effect in skeletal muscle cells. Four of the tested compounds 1, 5, 6 and 7 showed significant stimulation of GLUT4 translocation to cell surface in skeletal muscle cells without any adverse effect on cell viability. Effect of these four compounds was concentration-dependent and comparable to standard drug rosiglitazone. These findings indicate that constituents of K. pinnata may provide leads for the therapeutics for insulin resistance and diabetes.  相似文献   
100.
Soil physical degradation is one of the serious production constraints in the Indo-Gangetic Plain region. The present investigation was undertaken to study the effect of different nutrient management practices involving the use of fertilizer NPK alone or in combination with Farm Yard Manure (FYM), sulphitation pressmud (SPM), or induced defoliation (ID, imposed in pigeonpea through foliar spray of 10% urea solution at physiological maturity) on soil hydrophysical properties of a Typic Haplustepts under pigeonpea-wheat sequence, in a field experiment that continued for 5 years at IARI, New Delhi. Fertilizer NPK at recommended rate to both the crops resulted in a significant increase in macroaggregates, mean weight diameter, geometric mean diameter, water-stable aggregates, and saturated hydraulic conductivity in surface soil. Conjoint use of fertilizers, organic manures, and ID also decreased soil bulk density (0–15?cm) significantly over control. Effectiveness of organics and ID in improving soil physical environment was in the order: FYM?>?ID?>?SPM.  相似文献   
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