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201.
The aim of the study was to evaluate the use of laparoscopy for the assessment of the reproductive tract and stage of gonadal development of the tench (Tinca tinca). Laparoscopy was carried out from February to March 2009, on 30 anesthetized tenchs, 15 males and 15 females, of approximately 250 g bodyweight and 30 cm length, using a 1.9‐mm rigid cystoscope. Male and female gonads, attached to the swim bladder, were visualized. Testes were orange with a striped appearance. Mature ovaries were cluster‐shaped and whitish. Histological samples were collected, from the reproductive organs of both the sexes, with a forceps and showed the presence of gametes at different stages of maturity. The application of this minimally invasive diagnostic imaging technique could clinically be used as a powerful tool to evaluate the gender and to establish the reproductive status of tench and other fish.  相似文献   
202.
The aim of this study was to determine how phosphorus (P) concentration affects growth, concentration and distribution of nutrients in Leucospermum cordifolium ‘Flame Spike’ (Proteaceae). The trials were performed at the School of Agriculture (ETSIA) of the University of La Laguna (28° 28′ 43′′ N, 16° 19′ 7′′ W) with 64 plants (1-year-old) grown for 12 months in silica sand, fed with nutrient solutions containing different levels of Pi (5, 10, 15 and 20 mg L?1). At 6, 9, and 12 months, whole plants were taken from each experimental unit and divided into root, stem (main, first, second, and third growth) and leaves (adult, first, second, and third growth), which were measured, weighed, and analyzed. The data enabled a nutritional diagnosis, including the limiting P concentrations and nutrient interactions. P concentrations above 5 mg L?1 caused a reduction in growth, which in the third samples was significant (P < 0.05). Plants treated with 15 and 20 mg L?1 P attained similar dry weights (P > 0.05). Some young leaves showed a certain degree of chlorosis, probably due to iron (Fe) deficiency. Fully developed young leaves (YFEL) were suitable for nutritional diagnosis of P, and the P concentration of the nutrient solution affected the foliar manganese (Mn) concentration. This latter factor was related to the zinc (Zn) concentration in the roots.  相似文献   
203.
Aiming to support the use of native species from the Atlantic Rainforest in local agroforestry systems, we analysed chemical and biochemical components related to leaf decomposition of Inga subnuda, Senna macranthera, Erythrina verna, Luehea grandiflora, Zeyheria tuberculosa, Aegiphila sellowiana, and Persea americana. These tree species are native (except for P. americana) and commonly used in agroforestry systems in the Atlantic Rainforest. For the three first species (Fabaceae), we also analysed the remaining dry matter and released nutrients from leaves, using litter bags, and biological nitrogen fixation, using Bidens pilosa and Brachiaria plantaginea as references of non-N2-fixing plants. Leaves from I. subnuda, L. grandiflora, and P. americana had a lower decomposition rate than the other species, exhibiting negative correlations with lignin/N and (lignin+polyphenol)/N ratios. The percentages of remaining dry matter after 1 year were 69 % (I. subnuda), 26 % (S. macranthera) and 16 % (E. verna). Higher nutrient release was found in decreasing order from residues of E. verna, S. macranthera, and I. subnuda. The percentages of nitrogen fixation were 22.6 % (E. verna), 20.6 % (I. subnuda) and 16.6 % (S. macranthera). Diversification of tree species in agroforestry systems allows for input of diversified organic material and can contribute to maintaining and improving soil functions resulting in improvements of soil quality.  相似文献   
204.
Summary

The aims of the work were in vitro selecting for tolerance to high culture pH (CpH) in kiwifruit and evaluating the effects of selection pressure exerted by pH variations during regeneration. Leaf-derived ‘Tomuri’ and ‘Hayward’ kiwifruit (Actinidia deliciosa) somaclones, which had been regenerated at pH 5.7, 7 and 7.5, were compared to each other and to controls (i.e. cultures derived from ‘Tomuri’ and ‘Hayward’ mother plants through standard micropropagation techniques) for shoot growth, proliferation and appearance when cultured at up to pH 8. The proliferation rate (PR), the number of nodes (NN) produced by each shoot and axillary shoot length (ASL) decreased in all ‘Tomuri’ and ‘Hayward’ somaclones and in controls as culture pH increased. At CpH 8, ‘Tomuri’ somaclones regenerated at pH 7.0 generally tended to have higher average PR and NN than the other somaclones and control; their ASL also exceeded that of the other somaclones and was just slightly higher than in control. Regardless of CpH, ‘Hayward’ somaclone 7.5-1 tended to have higher PR, NN and ASL than other female somaclones. When shoot growth and appearance (tissue hyperhydricity, leaf yellowing or browning) were considered together through a multivariate data analysis, most ‘Tomuri’ and ‘Hayward’ somaclones which appeared less sensitive than controls to high CpH had been regenerated at pH 7 and 7.5. These regeneration and culture methods, especially the selection pressure exerted by the high pH during regeneration, thus seem to be effective in obtaining ‘Tomuri’ and ‘Hayward’ variants tolerant to high culture pH.  相似文献   
205.
Summary

The present work investigated the effects of different aqueous extracts of organic waste compounds on growth, proliferation and photosynthetic activity in ‘M9’ (Malus domestica Borkh.) shoot cultures, with the aim of determining the feasibility of using in vitro cultures as a tool for the rapid evaluation of organic amendments in agriculture. Aqueous extracts of the following organic waste compounds: cow manure (CM), sugarbeet industrial waste (SB), mixed grape, poultry and municipal solid waste (GPM), and citrus pruning and industrial waste (CPI) were prepared at a rate of 1:10 (w/v) compound:distilled water. The basal media used in the proliferation phase were: (i) PM1, modified Murashige and Skoog (MS) enriched with 4.4 µM 6-benzyladenine (BA); (ii) PM2, as PM1 but with a reduced cytokinin concentration (1 µM BA) to evaluate possible hormone effects; and (iii) PM3, 4.4 µM BA with reduced salt strength (0.33 MS) to induce nutrient deficiency. Hormone-free medium with half-strength MS salts was used for rooting. All media were enriched with each extract at 0, 0.2, 2, 20 or 200 ml l–1. Photosynthetic activity was measured on PM3 medium enriched with SB or CM. Standard culture conditions were 22° ± 2°C, with a 16 h photoperiod at 30 µmoles photosynthetically active radiation (PAR) m–2 s–1, but at 80 µmoles PAR m–2 s–1 to determine photosynthetic activity. Shoot weight increase in PM1 was not affected by the GPM and CPI extracts, while the growth trends of CM- and SB-treated shoots were described by a second-degree function with maxima at 2 ml l–1 and 0.2 ml l–1, respectively. Shoot proliferation for SB was represented by a quadratic curve (maximum at 2 ml l–1), was linearly reduced as GPM increased, but was not affected by CM or CPI. Treatments did not significantly affect rooting percentage and root length; however root number was increased by SB at 2 ml l–1.CO2 fixation increased linearly with both SB and CM, despite reduced growth at the highest levels of extract.  相似文献   
206.
Aspergillus spp. may induce equine respiratory infections such as fungal pneumonia, guttural pouch mycosis, and systemic infection in immunocompromised individuals. This study describes a case of probable respiratory aspergillosis in a horse presenting clinical signs of the upper airway disease different from those previously reported. Nasopharyngeal swabs and guttural pouch centesis were performed, and Aspergillus flavus was isolated and identified. Following 30 days of pharmaceutical treatment with itraconazole, clinical signs resolved. Results suggested that aspergillosis should be included in the differential diagnosis of upper airway infections, guttural pouch centesis may be useful to make a correct diagnosis, and itraconazole is efficacious in the treatment of A flavus infection.  相似文献   
207.
Porcine enteroviruses (PEVs) and teschoviruses (PTVs) are described as causative agents of neurological disorders, fertility disorders and dermal lesions of swine. Difficulties in the serological detection of these viruses may lead to a significant underestimation of infections with clinical symptoms. With the recent availability of genome sequence data for all the serotypes, molecular diagnosis is a possibility. The present study describes a new approach to molecular 'serotyping' of PTVs and PEV-B viruses, involving the amplification and sequencing of a genomic fragment of the VP1 coding region. A molecular characterization of Italian entero-teschovirus isolates was performed using a set of previously published and newly designed polymerase chain reaction primers. A total of 33 porcine isolates and 10 reference strains were analysed. Porcine enterovirus-B samples were first diagnosed as positive for enterovirus by amplification of the 5'-non-translated region. Samples were then typed by amplification and sequencing of a portion of the VP1 coding region. Porcine enterovirus-A and PTVs were detected by a published assay in the 5'-NC region that allows them to be differentiated according to the size of amplification product, using the same set of primers. For serotype characterization of PTV, we evaluated four different regions: the N terminus of the capsid protein VP2, the region encoding for RNA-dependent RNA polymerase, and the capsid VP1 and VP4 regions. The newly designed primers in the VP1 region was proved to be broad in range and suitable for serotype assessment and therefore constitute a useful diagnostic tool for molecular diagnosis of porcine teschovirus/enterovirus strains and for the study of molecular epidemiology and evolution of these viruses.  相似文献   
208.
Lavandula vera D.C., Lavandula×alardii and eight different L. hybrida Rev. cultivars cultivated at the Herb Garden of Casola Valsenio (Italy), found naturally infected by Alfalfa mosaic virus (AMV), have been evaluated for the influence of their pathologic status on essential oil biosynthesis and quality. The viral disease, consisting of a “yellow mosaic” on leaves and stems, was identified by means of electron microscopy, RT-PCR-RFLP and PAS-ELISA assays. Molecular characterization of the coat protein gene of four AMV isolates suggested that three of them belonged to subgroup I (from cvs. Ordinario and Grosso, Lavandula×alardii), while the isolate from cv. Sumiens showed molecular features of subgroup II. The infection of Lavandula plants by AMV (of the two subgroups) was found to decrease essential oil secretion. Changes in the relative composition regarded the linalool-linalyl acetate ratio; the overall increase in terpenic esters and in some cases increased sesquiterpenic abundance. Infection caused by AMV subgroup II isolate influenced negatively the quality of the essential oil much more than AMV isolates belonging to subgroup I. The importance of the phytopathological status of essential oil bearing crops is outlined.  相似文献   
209.
Here we present a case of preputial benign fibrous histiocytoma in a 7‐year‐old mule. This case was treated surgically. Pathologic analysis and diagnosis of these lesions were based on a combination of light microscopy and immunohistochemistry. Histologically, the tumour was composed primarily of a storiform pattern of fibroblastic and poligonal cells. In immunohistochemistry, except for consistent immunoreactivity for vimentin, nearly all tumour cells were positive for CD68, S‐100 protein, pan‐cytokeratin, alpha‐smooth muscle actin, and desmin. Benign fibrous histiocytoma of the prepuce in mule is rarely reported in veterinary literature.  相似文献   
210.
Clinicopathological Features of an Equine Ovarian Teratoma   总被引:1,自引:0,他引:1  
The present study describes the clinicopathological features of a mature cystic ovarian teratoma occurred in a 4 year old, cyclic, nulliparous Andalusian mare. The mass was discovered in the left ovary during a breeding soundness examination, and was hard in consistency and variously echogenic. Laparoscopy was performed to confirm the neoplastic change, followed by a unilateral laparotomic ovariectomy in the standing animal. On the cut surface the teratomatous ovary showed a large cyst filled with hair and sebaceous material and three small cysts containing mucous fluid, surrounded by solid areas where bone and cartilage could be recognized. Exceptionally, functional remnants of the ovary, including small follicles and a diestral corpus luteum were found near the tubal extremity. Histology revealed mature tissues foreign to the ovary including stratified squamous and respiratory epithelia, mucous, sebaceous and sweat glands, muscle fibres, fat and nervous tissue. The appearance of tracheal and lung architecture was occasionally observed.  相似文献   
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