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991.
Zahir Ahmad Zahir Muhammad Zafar-ul-Hye Saima Sajjad Muhammad Naveed 《Biology and Fertility of Soils》2011,47(4):457-465
Three plant growth-promoting rhizobacteria strains containing ACC-deaminase (Pseudomonas jessenii, Pseudomonas fragi, and Serratia fonticola) and Rhizobium leguminosarum were selected and characterized by conducting some experiments under axenic condition. The selected isolates had the potential
to improve the growth of lentil seedlings under axenic conditions. Pot and field experiments were conducted to evaluate the
potential of these selected strains for improving growth and yield of lentil under natural conditions. A classical triple
response (reduction of stem elongation, swelling of hypocotyle, and change in the direction of growth) bioassay was also conducted
to evaluate the effect of high ethylene concentration on the growth of etiolated lentil seedlings, and the performance of
coinoculation was evaluated to reduce the classical triple response in comparison with cobalt (Co2+), a chemical inhibitor of ethylene. Results showed that coinoculation of Pseudomonas and Serratia sp. with R. leguminosarum significantly increased the growth and yield of lentil. However, synergistic/coinoculation effect of P. jessenii with R. leguminosarum was more pronounced compared to that with P. fragi and S. fonticola. It increased the number of pods per plant, number of nodules per plant, dry nodule weight, grain yield, and straw yield up
to 76%, 196%, 109%, 150%, and 164% under pot and up to 98%, 98%, 100%, 82%, and 78%, respectively, under field conditions
as compared to uninoculated control. Similarly, combined inoculation significantly increased N concentration of grains under
both pot and field conditions. The results from classical triple response assay showed that the effects of classical triple
response decreased due to coinoculation in etiolated lentil seedlings and due to a decrease in the ethylene concentration.
It is suggested that the strategy adopted by Pseudomonas sp. containing ACC-deaminase with Rhizobium to promote nodulation and yield by adjusting ethylene levels could be exploited as an effective tool for improving growth,
nodulation, and yield of lentil. 相似文献
992.
Soil organic carbon active fractions as early indicators for total carbon change under straw incorporation 总被引:1,自引:0,他引:1
Minggang Xu Yilai Lou Xiaolin Sun Wei Wang Muhammad Baniyamuddin Kai Zhao 《Biology and Fertility of Soils》2011,47(7):745-752
Changes in total organic C (C
T), water-soluble organic C (C
WS), microbial biomass C (C
MB), C mineralization, particulate organic C (C
P), labile organic C (C
L), C management index (CMI), and C storage in surface Hapli-Ustic Cambisol (0–20 cm) under straw incorporation after both
2- and 10-year durations were investigated in a maize (Zea mays L.) field experiment in northeast China, in order to examine the effectiveness of these active C fractions and CMI as early
indicators for total C change. The treatments included straw removal (0%S), 50% of straw incorporation (50%S), and 100% of
straw incorporation (100%S). Under the straw incorporation, C
T concentration and C storage did not significantly change under 2-year duration, while were significantly increased under
10-year duration. However, C
MB, total C mineralization (C
TM), C
P, and C
L, and CMI were significantly increased under the straw incorporation even after only 2-year duration, and the responses were
more significant after 10-year duration. There were positive correlations between all these C indicators with each other.
Our findings demonstrate that the measured active C fractions (except for C
WS) and CMI can provide an early indication of change in total soil organic C induced by straw incorporation. 相似文献
993.
Medina-Torres CE Mason SL Floyd RV Harris PA Mobasheri A 《Veterinary journal (London, England : 1997)》2011,190(2):e54-e59
The aim of this study was to determine if hypoxia and the hypoxia mimetic cobalt chloride regulate the activity of matrix metalloproteinase (MMP)-2 and -9 in cultures of equine hoof keratinocytes. These effects were assessed in primary cultures of laminar keratinocytes using gelatin zymography. Incubation of keratinocytes with cobalt chloride significantly increased the levels of active MMP-2 compared to untreated controls. Hypoxia significantly increased the expression of active MMP-2 and -9 in keratinocyte cultures. This up-regulation was observed after 6h and peaked at 24h. The study findings provide novel evidence of a potential link between hypoxia within the hoof and up-regulation of MMPs which may in turn result in damage to the lamellar basement membrane. 相似文献
994.
995.
Mohamed Vall O. Mohamed Ahmed Zein Elabidine O. Bouna Fouteye M. Mohamed Lemine Taleb Khyar O. Djeh Trifi Mokhtar Ali O. Mohamed Salem 《Scientia Horticulturae》2011
Twenty one date palm (Phoenix dactylifera L.) accessions originated from different date palm groves were studied to assess the overall degree of polymorphism, detect similarities between genotypes and assess important agronomic traits. Thirty vegetative and reproductive variables were scored and subjected to multivariate analysis. Results showed a considerable phenotypic diversity among local date palm germplasm. Principal component analysis (PCA) revealed that characters related to leaflets length and spine, fruit and seed sizes accounted for a large proportion of the observed variability. Cluster analysis (CA) showed a typically continuous phenotypic diversity among date palm accessions and little associations between accessions from same geographic origin. Also, some heterogeneity within accessions that received the same denomination was evidenced. 相似文献
996.
Kianoush Nikoumanesh Ali Ebadi Mehrshad Zeinalabedini Yolanda Gogorcena 《Scientia Horticulturae》2011
In this study, in order to know the variability for a rootstock breeding program genetic diversity and relationships among 55 Iranian almond genotypes and seven related Prunus species were investigated. Morphological and molecular analyses were used. Principal component analysis showed that three components explained 67.6% of the total morphological variation for the first year and 68.06% for the second year of the study. Leaf traits were predominant in the first component and contributed most of the total variation. Leaf length and width, as well as, leaf area were highly correlated with each other and correlated to vigor. Also a negative correlation was found between leaf length/width ratio and vigor. Ward's method was used to construct cluster from morphological data which allocated individuals into their respective species. Out of 100 pre-screened RAPD primers, 16 with reproducible bands and maximum polymorphism were selected. Two-hundred and sixty bands were scored of which 250 of them were polymorphic. Average value of polymorphism per primer was 95.81% and maximum value for polymorphism (100%) was obtained from TIBMBA-14, TIBMBA-17, TIBMBB-05, TIBMBB-08, TIBMBD-09, and TIBMBD-10. On the other hand, the minimum value was obtained from TIBMBB-16 (86%). Primer TIBMBB-5 gave the maximum number of bands (25 fragments) and the minimum obtained from TIBMBE-18 (11 fragments). Genetic similarity based on Jaccard's coefficient ranged from 0.28 to 0.79 with an average of 0.53. Molecular analysis revealed a high degree of separation among samples regarding their geographical origin. Correlation between two approaches was low (R = −0.38). High molecular and morphological variability indicated that this collection includes rich and valuable plant materials for almond rootstock breeding. 相似文献
997.
The aim of this study was to investigate the anatomy of the arterial supply and branches of the thoracic limb of the porcupine. With this aim, five (three male and two female) adult porcupines were used. The vascular tree of the thoracic limb was injected through the common carotid arteries with coloured latex. The a. thoracica externa arose from the a. axillaris at the level of the fourth rib. It divided into two branches and went to the m. cutaneus trunci and the m. pectoralis ascendens. The a. subscapularis came off the a. thoracodorsalis. Later, the a. circumflexa humeri caudalis et cranialis, the three muscular branches and the a. circumflexa scapulae arose from the a. subscapularis. The a. profunda brachii arose together with the a. bicipitalis from the same truncus. The a. collateralis ulnaris left from the a. brachialis independently. Rete carpi dorsale was formed by the a. radialis. the r. carpeus dorsalis of the a. collateralis ulnaris and the a. interossea caudalis. Arcus palmaris profundus was formed by the r. profundus of the a. interossea caudalis and the r. palmaris profundus of the a. radialis. In conclusion, despite a partial resemblance to that in the rat, the distribution of the thoracic limb arteries in the porcupine was found to be completely different from that of other mammals. These findings represent, to our knowledge, the first study on the distribution of thoracic limb arteries in the porcupine. 相似文献
998.
J. D. H. Keatinge Asghar Ali B. Roidar Khan A. M. Abd El Moneim S. Ahmad 《Journal of Agronomy and Crop Science》1991,166(1):48-57
In the very large areas of arid highlands in West Asia, of which land over 1000 m in Balochistan is typical, as a result of rapidly increasing numbers of small ruminants and subsequent overgrazing of natural rangelands, severe shortages in animal feed are being experienced. To address this problem the And Zone Research Institute (AZRI) have been evaluating annual forage legume germplasm for adaptability to the harsh climatic conditions of highland Balochistan. Due to the marginality of the environment for sustained crop production an unconventional germplasm evaluation strategy has been adopted which emphasizes the introduction of landraces, particularly of the genus Vicia. The substantial risk of crop failure from either cold or drought, in any year, makes continuity of seed supply of selected lines a major problem. Support from ICARDA in Syria for re-supply of seed is a major advantage to the AZRI program.
In the last three years some tangible progress has been made in selection. V. villosa ssp. dasycarpa Ace. 683 has with autumn sowing shown sufficient cold tolerance and is highly productive in wet years. V. ervilia Ace. 2542 has shown some potential for drought tolerance which could be exploited for spring sowing. 相似文献
In the last three years some tangible progress has been made in selection. V. villosa ssp. dasycarpa Ace. 683 has with autumn sowing shown sufficient cold tolerance and is highly productive in wet years. V. ervilia Ace. 2542 has shown some potential for drought tolerance which could be exploited for spring sowing. 相似文献
999.
Hydatidosis was seen in 38.90% of cattle, 33.06% of buffaloes and 58.9% of camels slaughtered at a local abattoir. No statistically significant seasonal difference in prevalence was observed. Most cysts (63.14%) were infertile. Protein and carbohydrate contents of fluid from fertile and infertile cysts did not differ significantly. Sensitivity, specificity and efficiency of indirect haemagglutination test and enzyme-linked immunosorbent assay were low. 相似文献
1000.
A. Kadir B.H. Ali G. Al Hadrami A.K. Bashir M.F. Landoni & P. Lees 《Journal of veterinary pharmacology and therapeutics》1997,20(1):54-60
Phenylbutazone was administered intravenously and intramuscularly at a dosage rate of 4.4 mg/kg to a group of 6 female camels in a two-period crossover study. After intravenous (i.v.) administration, disposition was characterised by a two-compartment open model, with a low volume of distribution (0.174 l.kg–1 ), and distribution and elimination half-lives of 0.43 and 12.51 h, respectively. After intramuscular (i.m.) dosing absorption was relatively rapid with absorption half-time and time of maximal concentration values of 1.14 and 3.95 h, respectively. Plateau concentrations of phenylbutazone in plasma were obtained between 2 and 12 h and mean bioavailability was 97%, although this was subject to wide inter-animal differences. Plasma concentrations of the phenylbutazone metabolite, oxyphenbutazone, were low after iv dosing and generally undetectable after im administration, indicating that it is unlikely to contribute significantly to the pharmacological effects produced by phenylbutazone administration. An indication was obtained that phenylbutazone inhibited the ex vivo synthesis of serum thromboxane B2 (TxB2 ) for 24 h after i.v. dosing, but this finding requires confirmation. 相似文献