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51.
The morphology and length of roots and shoots of tomato (Lycopersicon esculentum Mill.) seedlings grown on a nutrient medium for fourteen days in a controlled environment chamber were apparently not affected, whereas the dry matter content of roots was significantly enhanced when 200 mg L?1 of humic acid (HA) isolated from either a non-amended soil or a sewage-sludge-amended soil was present in the nutrient medium. In contrast, the HA-like fraction isolated directly from the sewage sludge caused, under the same conditions, extensive alterations of tomato morphology and a significant reduction of the length and dry weight of both shoots and roots. The presence in the nutrient medium of the herbicides alachlor or imazethapyr at concentrations of 1 and 0.01 mg L?1, respectively, caused a marked decrease of tomato root and shoot length and dry weight. Differently, the herbicide rimsulfuron at a concentration of 0.01 mg L?1 produced a slight decrease in shoot and root length and a slight increase in their dry weight. A combination of 200 mg L?1 soil HA and each of the herbicides alachlor, rimsulfuron and imazethapyr at concentrations of 1, 0.01 and 0.01 mg L?1, respectively, in the nutrient medium attenuated the growth depression of tomato shoots and roots observed in the presence of the herbicide alone. However, the simultaneous presence of sewage sludge HA and any herbicide in the nutrient solution caused negative synergistic effects on tomato growth. The volume of nutrient solution and the amount of electrolytes taken up by tomato plants during the growth experiments correlated highly significantly with the total plant dry weight. Tomato seedlings induced a pH decrease in the nutrient medium in all treatments except in those where sludge-HA was present, either alone or in combination with any herbicide. 相似文献
52.
Spada E Proverbio D della Pepa A Perego R Baggiani L DeGiorgi GB Domenichini G Ferro E Cremonesi F 《Journal of Feline Medicine and Surgery》2012,14(6):369-377
Stray cat colonies in urban and rural areas of Lombardy, northern Italy, were surveyed for seroprevalence of feline immunodeficiency virus (FIV) antibodies, feline leukaemia virus (FeLV) antigen and Toxoplasma gondii IgG. Of 316 cats tested, 6.6% were positive for FIV and 3.8% were positive for FeLV infection; 203 cats were tested for T gondii IgG antibodies and a prevalence of 30.5% was detected. Statistical analysis tested the influence of provenience, age, gender, health status and laboratory results on seroprevalence and found male gender and adult age were risk factors for FIV infection. FIV-infected cats were more likely to have a decreased red blood cell count than FIV seronegative cats. No predictors were significantly associated with FeLV and T gondii seropositivity. Colony cats in this study posed a limited risk for retrovirus infection to pet cats allowed outdoors, whereas toxoplasmosis exposure was comparable with the worldwide data. 相似文献
53.
The Mauve Stinger Pelagia noctiluca (Forssk?l, 1775). Distribution,Ecology, Toxicity and Epidemiology of Stings. A Review 下载免费PDF全文
The toxicity of Cnidaria is a subject of concern due to its influence on humans. In particular, jellyfish blooms can highly affect human economical activities, such as bathing, fishery, tourism, etc., as well as the public health. Stinging structures of Cnidaria (nematocysts) produce remarkable effects on human skin, such as erythema, swelling, burning and vesicles, and at times further severe dermonecrotic, cardio- and neurotoxic effects, which are particularly dangerous in sensitive subjects. In several zones the toxicity of jellyfish is a very important health problem, thus it has stimulated the research on these organisms; to date toxicological research on Cnidarian venoms in the Mediterranean region is not well developed due to the weak poisonousness of venoms of jellyfish and anemones living in this area. In spite of this, during last decades several problems were also caused in the Mediterranean by stinging consequent to Cnidarian blooms mainly caused by Pelagia noctiluca (Forsskål, 1775) which is known to be the most venomous Mediterranean jellyfish. This paper reviews the knowledge on this jellyfish species, particularly considering its occurrence and toxicity. 相似文献
54.
Campeol E Flamini G Cioni PL Morelli I Cremonini R Ceccarini L 《Journal of agricultural and food chemistry》2003,51(7):1994-1999
The chemical composition of the volatile fractions from leaves of three Olea europaea L. cultivars (Leccino, Frantoio, and Cipressino) harvested at two different times of the year were examined by GC and GC-MS. The results showed a high content of aliphatic aldehydes in the three cultivars during both harvesting periods and an increase of (E)-2-hexenal (an aldehyde with high antimicrobial properties) percentage from July to November. 相似文献
55.
Adam J. Andrews Christophe Pampoulie Antonio Di Natale Piero Addis Darío Bernal-Casasola Veronica Aniceti Gabriele Carenti Verónica Gómez-Fernández Valerie Chosson Alice Ughi Matt Von Tersch Maria Fontanals-Coll Elisabetta Cilli Vedat Onar Fausto Tinti Michelle Alexander 《Fish and Fisheries》2023,24(6):1067-1083
During recent decades, the health of ocean ecosystems and fish populations has been threatened by overexploitation, pollution and anthropogenic-driven climate change. Due to a lack of long-term ecological data, we have a poor grasp of the true impact on the diet and habitat use of fishes. This information is vital if we are to recover depleted fish populations and predict their future dynamics. Here, we trace the long-term diet and habitat use of Atlantic bluefin tuna (BFT), Thunnus thynnus, a species that has had one of the longest and most intense exploitation histories, owing to its tremendous cultural and economic importance. Using carbon, nitrogen and sulphur stable isotope analyses of modern and ancient BFT including 98 archaeological and archival bones from 11 Mediterranean locations ca. 1st century to 1941 CE, we infer a shift to increased pelagic foraging around the 16th century in Mediterranean BFT. This likely reflects the early anthropogenic exploitation of inshore coastal ecosystems, as attested by historical literature sources. Further, we reveal that BFT which migrated to the Black Sea–and that disappeared during a period of intense exploitation and ecosystem changes in the 1980s–represented a unique component, isotopically distinct from BFT of NE Atlantic and Mediterranean locations. These data suggest that anthropogenic activities had the ability to alter the diet and habitat use of fishes in conditions prior to those of recent decades. Consequently, long-term data provide novel perspectives on when marine ecosystem modification began and the responses of marine populations, with which to guide conservation policy. 相似文献
56.
Elisabetta Mancinelli Kevin Eatwell Anna Meredith 《Journal of Exotic Pet Medicine》2013,22(3):293-300
A 3-month-old female degu (Octodon degus) was presented because blood was noticed in its cage. On physical examination, firm masses were palpable within the caudal abdomen and traces of blood appeared to be coming from the patient’s vaginal opening. Radiographic images showed areas of ill-defined mineralization within the uterus, consistent with fetus formation. Three fetuses could be identified. Ultrasound examination of the degu failed to confirm viable fetal heartbeats. Pregnancy failure with fetal death was suspected. Overnight 1 fetus was passed, but medical therapy with oxytocin failed to induce delivery of the 2 remaining fetuses by the following morning. The degu was therefore anesthetized, an ovariohysterectomy was performed, and the patient made an uncomplicated recovery. Histopathological examination of the fetuses failed to identify any abnormalities. In the uterus, histology confirmed a minimal to mild diffuse, chronic active endometritis. The definitive cause of fetal death was not identified. 相似文献
57.
58.
Mariano Catanesi Giulia Caioni Vanessa Castelli Elisabetta Benedetti Michele dAngelo Annamaria Cimini 《Marine drugs》2021,19(1)
Marine habitats offer a rich reservoir of new bioactive compounds with great pharmaceutical potential; the variety of these molecules is unique, and its production is favored by the chemical and physical conditions of the sea. It is known that marine organisms can synthesize bioactive molecules to survive from atypical environmental conditions, such as oxidative stress, photodynamic damage, and extreme temperature. Recent evidence proposed a beneficial role of these compounds for human health. In particular, xanthines, bryostatin, and 11-dehydrosinulariolide displayed encouraging neuroprotective effects in neurodegenerative disorders. This review will focus on the most promising marine drugs’ neuroprotective potential for neurodegenerative disorders, such as Parkinson’s and Alzheimer’s diseases. We will describe these marine compounds’ potential as adjuvant therapies for neurodegenerative diseases, based on their antioxidant, anti-inflammatory, and anti-apoptotic properties. 相似文献
59.
60.
Previous studies revealed that defoliation can bring about differential responses in maize (Zea mays L.) genotypes for cold tolerance. This research was conducted to study the inheritance of the responses to defoliation for germination at low temperature and for seedling traits in early-sown field trials. Six inbred lines were crossed according to the complete diallel scheme, thus producing 36 genotypes. At milk ripening stage, half of the plants of each genotype were completely defoliated (D) whereas the other half were not (ND). Two experiments were conducted for two years, one in the germinator and one in the field. The response to defoliation was evaluated as (D–ND). Across the two years, the D treatment caused an average kernel weight decrease of ?56 mg (?23.1 % as referred to ND), an increase of 2.3 % for germination at 9 °C (G9) and a reduction of ?0.3 d for the average time of germination (ATG); in contrast, the defoliation effect was negligible for germination at 25 °C. In the field, the defoliation effects were more notable in the first (colder) year and led to an increase of 2.0 % for field emergence (FE) and to a decrease of ?2.7 g for seedling fresh weight (SFW). The genotypic variation for the (D–ND) response was significant for additive, dominance and reciprocal effects for G9, ATG, FE and SFW. There was consistency among lines across traits for additive effects, with Lo1016 and Os420 showing the best and the worst effect, respectively. 相似文献