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941.
In this part, 32 plants (rubiaceae tovitaceae) are investigated in a search for local tanning materials. Colour tests along with the chromatographic investigation of the free sugars and phenolic aglycones are given. A conclusion of all the plants previously studied is given discussing the collective data of the colour tests, free sugars and phenolic aglycones separately.
Zusammenfassung In diesem letzten Teil einer Serie von Veröffentlichungen über lokal vorkommende Pflanzen als potentielle Quelle für Gerbstoffe, werden die Untersuchungsergebnisse von weiteren 32 Pflanzen (aus den FamilienRubiaceae bisVitaceae) beschrieben.Farbtests, spezifisch für Tannine, zusammen mit chromatographischen Untersuchungen auf freie Zucker und phenolische Aglykone wurden durchgeführt.Zusammenfassend werden die Ergebnisse aus dem Farbtest, der Analysen auf freie Zucker und phenolische Aglykone an allen bisher in die Untersuchungen einbezogenen Pflanzen diskutiert.

Resume Trente-deux plantes (des familiesRubiaceae à Vitaceae) ont été examinées afin de déterminer le site de localisation des tannins. Les tests colorés et les résultats chromatographiques des sucres libres et des aglycones phénoliques sont décrits.Une conclusion de toutes les plantes déjà examinées du point de vue des tests colorés est présentée ainsi qu'une discussion générale des résultats individuels des sucres libres et des aglycones phénoliques.


Part VI, this journal: XX, 4 :297–309, 1971  相似文献   
942.
Efficacy of four different essential oils against the subterranean termite, Coptotermes curvignathus Holmgren, was assessed in various bioassays. Laboratory results indicate that the highest termite mortality was found in Dipterocarpus sp. essential oil after 24 h (LC50 = 1.62 %) and the lowest in Melaleuca cajuputi (LC50 = 4.60 %). The wood consumption in the filter paper treated with Dipterocarpus sp. oil is also smaller than for the other three essential oils tested. However, the other three essential oils also inhibited termite susceptibility of the specimens. Dipterocarpus sp. (keruing oil) was the most effective insect antifeedant and repellent against C. curvignathus. The results suggest that essential oils might have some beneficial activity of economic value and are considered good candidates for the development of new chemicals (repellents or antifeedants) for termite control.  相似文献   
943.
Veterinary Research Communications - Avian influenza viruses (AIV) increase commercial and backyard poultry mortality and morbidity, reduces egg production, and elevates public health risk....  相似文献   
944.
Gmelina arborea Roxb. is a fast-growing, deciduous tree species native to Bangladesh. It has been widely planted since 1992 for commercial production of pulpwood in hilly areas of Bangladesh. The purpose of this study was to derive well-fitting allometric models for estimation of aboveground biomass, and carbon and nutrient (nitrogen, phosphorus and potassium) stocks in G. arborea to ensure sustainable production and management of this species. Eight linear models with 64 regression equations were tested for estimation of aboveground biomass, carbon and nutrient stocks in different parts (leaves, branches, bark and stem) of the plant. The best-fitting allometric models were selected in accordance with various relevant statistical criteria.  相似文献   
945.
This study investigated the knockdown (KD) of Kid on maturation developmental competence and multinucleation of mouse germinal vesicle (GV) oocytes after parthenogenetic activation. Data revealed that Kid messenger RNA (mRNA) was expressed in GV and MII stage oocyte and 1‐ and 2‐cell embryos. Additionally, Kid mRNA expression in the Kid KD group decreased by nearly 46% compared to the control small interfering RNA (siRNA) groups. The rate of multinucleated embryos in the Kid KD group (52.4%) was significantly higher (P < 0.05) than the control siRNA group (4.7%). Finally, the developmental rates were significantly lower in the Kid siRNA group at > 4‐cell stage (28.6% vs. 53.5%) and the blastocyst stage (2.4% vs. 23.3%) compared to the control siRNA groups. Suppression of Kid using siRNA caused multinucleation in early embryos with high frequency and it may increase 2‐ to 4‐cell arrested embryos and reduce the developmental competence to blastocyst.  相似文献   
946.
947.
Growing concerns for food security and the alleviation of hunger necessitate knowledge-based crop management technologies for sustainable crop production. In this study, 13 winter bread wheat genotypes (old, relatively old, modern, and breeding lines) were evaluated under three different tillage systems, i.e., conventional tillage (CT, full tillage with residue removed), reduced tillage (RT, chisel tillage with residue retained) and no-tillage (NT, no-tillage with residue retained on the soil surface) in farmer's fields under rainfed conditions using strip-plot arrangements in a randomized complete block design with three replications in the west of Iran (Kamyaran and Hosseinabad locations) over two cropping seasons (2018–2019 and 2019–2020).The main objectives were to investigate the effects of tillage systems and growing conditions on the agronomic characteristics, grain yield and stability performance of rainfed winter bread wheat genotypes.Significant (P<0.01) genotype×tillage system interaction effects on grain yield and agronomic traits suggested that the genotypes responded differently to the different tillage systems. The number of grains per spike and plant height were positively (P<0.0) associated with grain yield under the NT system, so they may be considered as targeted traits for future wheat breeding. Using statistical models, the modern cultivars (“Sadra” and “Baran”) were identified as high yielding and showed yield stability across the different tillage systems. As per each tillage system, genotype “Sadra” followed by “Zargana-6//Dari 1-7 Sabalan” exhibited higher adaption to CT; while cultivars “Jam” and “Azar2” showed better performance under the RT system; and cultivars “Varan” and “Baran” tended to have better performance expression in the NT condition.The increased grain yields achieved in combination with lower costs and greater profits from conservation agriculture suggest that adapted cultivar and NT systems should be evaluated and promoted more widely to farmers in the west of Iran as an attractive package of crop management technologies.In conclusion, variations in the performance of genotypes and the significant genotype×tillage system interaction effects on grain yield and some agronomic traits assessed in this study suggest that the development and selection of cultivars adapted to the NT system should be considered and included in the strategies and objectives of winter wheat breeding programs for the temperate and cold dryland conditions of Iran.  相似文献   
948.
The J wave has never been documented in the electrocardiogram (ECG) of cats presenting with hypertrophic cardiomyopathy (HCM). The present study aimed to describe the presence, morphology, amplitude, and duration of J waves in cats with HCM. It included 20 apparently healthy cats and 45 cats diagnosed with HCM based on clinical, echocardiographic, ECG, and radiographic examination. The cats were of different breeds (Persian: 40, domestic short hair: 21, Siamese: 4), ages (6.01 ± 4.34 years), sexes (male: 33, female: 32), and weights (3.30 ± 1.51 kg). The J wave was absent in the ECGs of the healthy population, but was detected in 29 out of 45 cats with HCM (63%). The J waves were observed at the QRS-ST junction in more than one limb lead of the ECG. Only positive deflections with an amplitude ≥0.05 mV were included, as measured by an ECG ruler in three consecutive heart cycles. The J waves were mainly present in leads II (n=20) and III (n=16), with amplitudes of 0.06 ± 0.02 and 0.08 ± 0.03 mV; their mean (± SD) duration was 0.16 ± 0.05 msec in lead II and 0.18 ± 0.05 msec in lead III. They occurred in both notched and slurred morphologies, with the latter being more common. In conclusion, J waves were a common finding in the ECGs of cats with HCM.  相似文献   
949.
Since natural fiber/polymer composites are increasingly used, the development of safe and environmental friendly flame retarding bio-based composites is of great importance. But this issue must maintain the mechanical performance of these composites. To study these objectives, four levels of magnesium hydroxide Mg(OH)2 of (0, 10, 20, 30 phc) and two levels of nanoclay (0, 3 phc) were considered and incorporated into HDPE/wheat straw composites. Maleic anhydride grafted polyethylene (PE-g-MA) was also used as a compatibilizer at constant content. The samples were prepared by melt compounding and injection molding processes, respectively. The some properties of samples including burning rate and mechanical properties (tensile and impact strengths) were tested based on the ASTM standard. The results showed that the burning rate of samples decreased with increasing the nanoclay and Mg(OH)2 content. The tensile and impact strengths showed a marginal reduction by adding Mg(OH)2 from 10 phc to 30 phc and the tensile modulus and impact strength revealed an increase by increasing the amount of nanoclay up to 3 phc. Generally, these results confirmed that the fire retarding and mechanical properties of HDPE/wheat straw composites could be significantly improved with an appropriate combination of the nanoclay and Mg(OH)2 in the composites.  相似文献   
950.
There is a general agreement that exposure to high concentrations of polynuclear aromatic hydrocarbons (PAH) in sediments is associated with high frequencies of neoplasms in feral fish species. Since PAH modulate the activity of murine and amphibian natural cytotoxic (killer) cells, a leukocyte subpopulation that is believed to play an important role in immunosurveillance, we wished to determine if fish exposed to PAH could have an altered natural cytotoxic cell (NCC) activity. In the present study, mummichog (Fundulus heteroclitus L.) were collected from two sites in the Elizabeth River, VA that are heavily contaminated with PAH, and from a relatively unpolluted reference site in the York River, VA. The cytotoxic activity of anterior kidney and splenic leukocytes was tested against the tumor cell line K562. The leukocytes from Elizabeth River fish displayed a significant depression of the in vitro tumorilytic activity as compared with leukocytes from the York River fish. Analysis of leukocyte-tumor cell conjugates indicated that Elizabeth River fish leukocytes were unable to recognize and subsequently bind to the tumor target cells. This suggests an aberration in the early events of the cytotoxic mechanism. By keeping the fish in cleaner York River water for up to 28 weeks the suppressed NCC activity was reversed totally in one site, which is slightly contaminated, and partially in the other site, which is heavily polluted with creosote from an operating wood treatment plant. This indicates that the decreased NCC activity was related, at least in part, to exposure to the chemical pollutants in the Elizabeth River sediments.  相似文献   
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