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排序方式: 共有255条查询结果,搜索用时 383 毫秒
141.
Ali Osman Demir Abdurrahim Tanju Göksoy Hakan Büyükcangaz Zeki Metin Turan Eyüp Selim Köksal 《Irrigation Science》2006,24(4):279-289
The response of sunflower (Helianthus annuus L.) to 14 irrigation treatments in a sub-humid environment (Bursa, Turkey) was studied in the field for two seasons. A rainfed (non-irrigated) treatment as the control and 13 irrigation treatments with full and 12 different deficit irrigations were applied to the hybrid Sanbro (Novartis Seed Company) planted on clay soil, at three critical development stages: heading (H), flowering (F) and milk ripening (M). The yield increased with irrigation water amount, and the highest seed yield (3.95 t ha−1) and oil yield (1.78 t ha−1) were obtained from the HFM treatment (full irrigation at three stages); 82.9 and 85.4% increases, respectively, compared to the control. Evapotranspiration (ET) increased with increased amounts of irrigation water supplied. The highest seasonal ET (average of 652 mm) was estimated at the HFM treatment. Additionally, yield response factor (k
y) was separately calculated for each, two and total growth stages, and k
y was found to be 0.8382, 0.9159 (the highest value) and 0.7708 (the lowest value) for the total growing season, heading, and flowering-milk ripening combination stages, respectively. It is concluded that HFM irrigation is the best choice for maximum yield under the local conditions, but these irrigation schemes must be re-considered in areas where water resources are more limited. In the case of more restricted irrigation, the limitation of irrigation water at the flowering period should be avoided; as the highest water use efficiency (WUE) (7.80 kg ha−1 mm−1) and irrigation water use efficiency (IWUE) (10.19 kg ha−1 mm−1) were obtained from the F treatment. 相似文献
142.
Comparing the performance of cereal varieties in organic and non-organic cropping systems in different European countries 总被引:4,自引:4,他引:0
M. Przystalski A. Osman E. M. Thiemt B. Rolland L. Ericson H. Østergård L. Levy M. Wolfe A. Büchse H.-P. Piepho P. Krajewski 《Euphytica》2008,163(3):417-433
Top ranking varieties are tested in multiple environments before and after registration in order to assess their value for
cultivation and use (VCU testing). Recently, interest has increased in obtaining varieties specifically adapted to organic
farming conditions. This raised the question if an independent system of trials may be required for this purpose. To help
answering this question, through the exchange network of European cereal researchers SUSVAR (), a number of data sets of agronomic traits from barley, wheat and winter triticale, from trials performed in Denmark, Sweden,
The Netherlands, France, Switzerland, UK and Germany, were made available and analysed using an approach based on mixed models
involving parameters describing genetic correlation between the two types of experiments, i.e., organic and non-organic (high
or low input). Estimated variance components and correlations were used to evaluate response to selection and index selection.
The response to index selection was analysed as a function of the fraction of available trials assigned to the organic system.
The genetic correlations were interpreted in terms of ranking agreement. We found high genetic correlations between both systems
for most traits in all countries. Despite high genetic correlations, the chances of very good agreement in observed rankings
were moderate. Combining information from both organic and non-organic systems is shown to be beneficial. Further, ignoring
information from non-organic trials when making decisions regarding performance under organic conditions is a sub-optimal
strategy. 相似文献
143.
S Hammami C L Schumacher F Cliquet J Barrat A Tlatli R Ben Osman T Aouina A Aubert M Aubert 《Veterinary research》1999,30(4):353-362
The safety of the SAG2 rabies virus, a highly attenuated mutant of the SAD strain intended to vaccinate dogs by the oral route, was evaluated in local Tunisian dogs and in five other local species likely to consume vaccine baits. These species were the domestic cat (Felis catus), the jackal (Canis aureus), the jerboa (Jaculus orientalis), the merion (Meriones sp.) and the gerbil (Gerbillus campestris). The vaccine was administered orally to 21 dogs, 11 cats and eight jackals and orally or intramuscularly to 62 wild rodents of the above-mentioned species. Seven dogs, one cat, five jackals all juvenile and with poor health status) and two rodents died for intercurrent causes. The others were observed for 60-180 days. No animal showed any rabies symptom. Seroneutralizing antibodies were observed in all experimental groups, only after vaccination, with the highest rate being observed in jackals and rodents. The rabies virus was detected in the oral cavity of three cats 6 h after oral instillation, but was not isolated later either in saliva or in salivary glands. Tissue samples (brain and salivary glands) from dead or euthanized animals were examined for the rabies virus antigen by a fluorescent antibody test. No rabies antigen was detected. These trials confirm the safety of the SAG2 strain on the Tunisian species already demonstrated by other authors on many other target and non target species. 相似文献
144.
Mohsina Mannan Seikh Razibul Islam Mahadi Hasan Osman Md. Khalilur Rahman Md. Naim Uddin Md. Kamal Md. Shaheed Reza 《Aquaculture Research》2020,51(5):2125-2133
The antibacterial effect of oxytetracycline (OTC) on bacterial load, pathogen and possible development of antibiotic resistance in intestinal flora of apparently healthy Nile tilapia (Oreochromis niloticus) was investigated under laboratory condition. OTC, a broad spectrum approved antibiotic widely used in aquaculture, was fed to Nile tilapia through medicated diet at a rate of 2 g/ kg of feed for consecutive 7 days in treatment 1 (T1) and 30 days in treatment 2 (T2). Changes in physico‐chemical parameters of water were also recorded where pH and dissolved oxygen influenced bacterial load and coliform count respectively. At the start of the experiment, initial bacterial load in fish intestine was 1.61 ± 2.25 × 1010 cfu/g, which after OTC treatment decreased significantly (p < .05) to 3.06 ± 2.08 × 108 cfu/g on day 7 and 3.45 ± 4.46 × 107 cfu/g on day 30 when compared with the control group. Among the 10 bacterial genera identified in the intestine, 4 potential public health concern bacteria viz., Salmonella, Escherichia, Enterobacter and Staphylococcaus were predominant. There was a sharp increase in bacterial load on day 18 in T2 that may be attributed to the development of antibiotic resistance in intestinal bacteria. Antibiotic susceptibility test for isolates against seven antibiotics: amoxycillin, ciprofloxacin, co‐trimoxazole, erythromycin, gentamicin, nitrofurantoin and tetracycline using disc diffusion method revealed significantly increased resistance of Gram‐negative rods (p < .05) that possibly caused increased frequency of OTC‐resistant microorganisms. In conclusion, short‐ and long‐term exposure to OTC treatment affected the distribution of bacterial genera including pathogens in the Nile tilapia gastrointestinal tract and concomitantly influenced their antimicrobial resistance. 相似文献
145.
Khadija Semhi Salah Al-Khirbash Osman Abdalla Tabisam Khan Joelle Duplay Sam Chaudhuri Salim Al-Saidi 《Water, air, and soil pollution》2010,205(1-4):343-357
The present study determines the source of dust particles and investigates their impact on the chemical compositions of plants and soils around a cement factory in Oman within a radius of 10 km of this disturbed ecosystem. A total number of nine samples of the species of plants (Rhazya stricta), nine samples of soils, and nine samples of dust were collected and analyzed for major ions and trace elements including rare earth elements (REEs). Principal component analysis applied to the major and trace element concentrations in the dust indicated the input of at least two sources to the dust in the study area: ophiolites and cement. The REE distribution in the plants and soils revealed that the most available elements to plants originated dominantly from ophiolites rather than from cement. The contribution of cement industry is significant only in the zone located at about 0.500 to 2 km around the cement factory, whereas the contribution of ophiolites increases with distance from the cement factory. 相似文献
146.
At Kafr El-Sheikh province, Egypt, out of 117 examined drafting horses, mites were detected in 20 (17.09%) horses. The recovered mites were 14 Chorioptes, four Psoroptes and two Sarcoptes whereas mites were not detected in four cases clinically showed typical mange lesions. Interestingly, neither the age nor the sex of the examined horses had a clear influence on the prevalence of the infection. Clinical signs observed in mange infested horses were in the form of irregular skin lesions, severe itching and sometimes biting of affected skin areas and decrease feed consumption. The skin lesions mainly start as erythematous area followed by developing of papules and crust formation. Skin scratches as a result of traumatized lesions usually occurred. Hair was lost on the affected parts developing irregular alopecic areas. Distribution of the lesions was varied according to the type of mite. Chorioptic mite was detected in para-anal fold, distal portion of legs and tail lesions, Psoroptic mite was detected in withers, mane, shoulder and flank lesions whereas Sarcoptic mite was isolated mainly from lesions on the head and neck. Complete clinical and parasitological cure for mite infestation were obtained within 2 weeks in both moxidectin and ivermectin treated groups with 100% recovery rate. Our results indicated that moxidectin oral gel is effective and good alternative for the treatment of chorioptic mange in horse to avoid drug resistance that may develop as a result of the intensive use of ivermectin alone for long periods. 相似文献
147.
148.
This study was performed on Van cats to determine the volumetric, morphometric and surface area measurement values of their cervical spinal cords (SC) and vertebral canals (CC) and the ratios between their dimensions using computed tomography (CT) images. The study also aims to reveal any biometric differences in these values between the two sexes. Spinal cord and vertebral canal CT images of 16 healthy adult Van cats (8 males and 8 females) were used in the study. First, three measurement points were selected for each vertebra on their cranial, medial and caudal sections along the sagittal axis. Next, the morphometric values were obtained using the transversal images of these measurement points. The surface areas for the SC and CC were calculated using the stereological planimetry method. The Cavalieri's principle was then used to calculate the relevant anatomic structure volumes. The obtained values were then statistically analysed. SC and CC were found to be larger in males in general, while ‘SC cranial/CC cranial’ and ‘SC medial/CC medial’ dimensions and volume ratios were found to be larger in female cats on average. Bodyweight and age values were found to have a negative correlation with SC and CC ratio, but the correlation was statistically insignificant. All SC and CC surface area and volume measurements were found to be higher in male cats (p < .05). We believe the results obtained by this study will provide valuable insight into veterinary clinicians in evaluating pathological lesions in the cervical spinal cord and vertebral canal CT scans. 相似文献
149.
A. Osman Akan 《Water, air, and soil pollution》1994,73(1):225-234
Snowmelt runoff presents an enhanced threat of environmental damage. Soluble impurities which have accumulated in the snow during winter months are transported to the lower portion of the snow cover early in the melting season due to melt-freeze cycles. These contaminants are removed rapidly at very high concentrations within the first fractions of snowmelt runoff causing sudden bursts of enriched pollutants. This paper reports a physically-based mathematical model to simulate the enrichment process in a snow cover. The model is based on the liquid water flow, heat transport, and pollutant transport equations. These nonlinear partial differential equations are solved simultaneously using a six-point implicit finite difference scheme. 相似文献
150.
A method has been developed for the quantitative analysis of total glycoalkaloids (TGA) in potato tubers. The method consists of TGA extraction by suitable solvent mixtures followed by hydrolysis of the glycosides and extraction of the aglycones. The aglycones are then quantitated by nonaqueous titration. The advantages of this method over those previously described are the inclusion of glycoalkaloids that are not measured by other methods, and the simplicity, safety, and rapid nature of the procedure. This method has been applied to the TGA analysis of potato tubers subjected to a variety of storage and treatment conditions. 相似文献