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171.
The human risk of infection with larvae of Toxocara canis was estimated in people from the Marche region of Italy. This region includes both urban and rural areas and its inhabitants frequently keep dogs for company, hunting, as guardians or shepherds. T. canis infection was diagnosed in 33.6% out of 295 dogs examined. Nearly half of the dogs (48.4%) living in rural areas were found T. canis positive, compared to about one-quarter of the dogs (26.2%) from urban areas. Analysis by provenance and role revealed the highest infection rate in rural hunting dogs (64.7%) and the lowest in urban companion dogs (22.1%). According to questionnaire data, the peridomestic environment, i.e. gardens and dog pens, is the most important defecation site in both rural and urban areas. Since over 40% of the dogs who defecate in dog pens are infected and 24% of urban and 47% of rural dogs who leave their droppings in the house surroundings harbour the parasite, it is clear that these environments may constitute sites of zoonotic risk. Our analysis of soil samples from 60 farms confirmed the high contamination level, revealing positive soil samples in more than half of the farms. Substantial egg contamination was also found in urban areas, as 3/6 parks examined were Toxocara spp. positive. Finally, our serological findings indicate that human infection actually occurs in the area: 7 out of 428 adults examined (1.6%) had very high levels of antibodies to T. canis antigen, suggesting a previous contact with the Larva migrans of the nematode.  相似文献   
172.
OBJECTIVE: To evaluate pulsed-wave Doppler spectral parameters as a method for distinguishing between neoplastic and inflammatory peripheral lymphadenopathy in dogs. SAMPLE POPULATION: 40 superficial lymph nodes from 33 dogs with peripheral lymphadenopathy. PROCEDURES: 3 Doppler spectral tracings were recorded from each node. Spectral Doppler analysis including assessment of the resistive index, peak systolic velocity-to-end diastolic velocity (S:D) ratio, diastolic notch velocity-to-peak systolic velocity (N:S) ratio, and end diastolic velocity-to-diastolic notch velocity ratio was performed for each tracing. Several calculation methods were used to determine the Doppler indices for each lymph node. After the ultrasonographic examination, fine needle aspirates or excisional biopsy specimens of the examined lymph nodes were obtained, and lymphadenopathy was classified as either inflammatory or neoplastic (lymphomatous or metastatic) via cytologic or histologic examination. Results of Doppler analysis were compared with cytologic or histopathologic findings. RESULTS: The Doppler index with the highest diagnostic accuracy was the S:D ratio calculated from the first recorded tracing; a cutoff value of 3.22 yielded sensitivity of 91%, specificity of 100%, and negative predictive value of 89% for detection of neoplasia. Overall diagnostic accuracy was 95%. At a sensitivity of 100%, the most accurate index was the N:S ratio calculated from the first recorded tracing; a cutoff value of 0.45 yielded specificity of 67%, positive predictive value of 81%, and overall diagnostic accuracy of 86.5%. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that noninvasive Doppler spectral analysis may be useful in the diagnosis of neoplastic versus inflammatory peripheral lymphadenopathy in dogs.  相似文献   
173.
Electrical stimulation of excitable cells provides therapeutic benefits for a variety of medical conditions, including restoration of partial vision to those blinded via some types of retinal degeneration. To improve visual percepts elicited by the current technology, researchers are conducting acute electrophysiology experiments, mainly in cats. However, the rat can provide a model of a range of retinal diseases and possesses a sufficiently large eye to be used in this field. This article presents a long‐term anesthetic protocol to enable electrophysiology experiments to further the development of visual prostheses. Six Long‐Evans rats (aged between 14 and 16 weeks) were included in this study. Surgical anesthesia was maintained for more than 15 h by combining constant intravenous infusion of ketamine (24.0–34.5 mg/kg/h), xylazine (0.9–1.2 mg/kg/h), and inhaled isoflurane in oxygen (<0.5%). Overall heart rate, respiratory rate, and body temperature remained between 187–233 beats/min, 45–58 breaths/min, and 36–38 °C, respectively. Neural responses to 200‐ms light pulses were recorded from the superior colliculus using a 32‐channel neural probe at the beginning and before termination of the experiment. Robust responses were recorded from distinct functional types of retinal pathways. In addition, a platinum electrode was implanted in the retrobulbar space. The retina was electrically stimulated, and the activation threshold was determined to be 5.24 ± 0.24 μC/cm2. This protocol may be used not only in the field of visual prosthesis research, but in other research areas requiring longer term acute experiments.  相似文献   
174.
A 15-year-old spayed female domestic shorthair cat presented with alopecia associated with hepatocellular carcinoma. Clinical signs, which had commenced 6 months previously, included loss of appetite, loss of weight, and depression. As reported by the owner, the cat developed alopecia a week before referral. The hair loss was localized to the ventral aspect of the thorax and abdomen, medial aspect of front and hind limbs, and ventral aspect of the tail, and was associated with histological features consistent with paraneoplastic alopecia. At necropsy, multiple hepatic nodules were observed, and subsequent histopathological investigation showed cords and sheets of hepatocyte-like neoplastic cells positive for the hepatocyte marker (Hep Par 1), thereby demonstrating the hepatocellular origin of the tumour, which was diagnosed as a hepatocellular carcinoma. This is the first report of feline paraneoplastic alopecia associated with hepatocellular carcinoma confirmed by the Hep Par 1 marker.  相似文献   
175.
A 4-year-old, intact male Labrador Retriever with a rapidly progressive conjunctival mass was evaluated. Ocular examination showed a 2-cm elongated mass arising from the superior bulbar conjunctiva of the left eye. The mass resulted in distortion of the palpebral fissure and contacted the superior aspect of the cornea without modifying its structure; no adhesion to the sclera was detected. The superior palpebral conjunctiva was unaffected, and the remaining ocular examination was normal. The initial diagnostic work-up included CBC, serum biochemical analysis, urinalysis, and fine needle biopsy of the mass. A poorly differentiated mast cell tumor was diagnosed by cytology. Immunocytochemistry was performed to evaluate Ki-67 proliferation index, and 54/1000 tumoral nuclei showed a dark red staining. After a complete clinical staging, the mass was excised and identified histologically as a grade-II mast cell tumor. An adjuvant treatment with prednisone and vinblastine was instituted because of the limited excisional margins. No evidence of local recurrence or metastasis has been apparent during the 29-month follow-up period. This report contributes to the current literature pertaining to canine conjunctival mast cell tumors; unfortunately, the paucity of case reports and the absence of large studies regarding this tumor make conclusions regarding its biologic behavior impossible.  相似文献   
176.
Lameness in pigs is a major welfare concern and one of the most commonly reported reasons for premature culling of breeding sows. In this study, the prevalence of lameness in sows was estimated using data from 76 pig breeding units in England and risk factors associated with the occurrence of lameness were examined. The prevalence of lameness in sows was 4.5% (farm median 5.0%, range 0–40%), with at least one lame sow being observed at 54% of the 76 farms. Relative risk (RR) of lameness was determined by multivariable Poisson regression analysis. Farms with high producing sows had a lower rate of lame sows than farms with a medium level of production (P = 0.01). However, medium levels of production on a farm were associated with higher levels of lameness than farms having the lowest level of production (P = 0.02). Farms where the stockman had responsibility for more sows resulted in an increased risk of lameness (P = 0.0062). When indoor units were considered, the area of the pen and younger sows (two parities or less) had higher risk of lameness (P = 0.001 and P = 0.026 respectively). An increased awareness of the risk factors behind lameness is essential in farm management and can be useful when designing housing areas as well as developing future prevention plans for lameness.  相似文献   
177.
The presence of carboxylic acids in grape products has been investigated for a long time by researchers, from both the qualitative and quantitative points of view. Evaluation of carboxylic acids requires the study and optimization of some operative variables which are strictly related to the matrix. In particular, the determination of organic acids in real matrixes such as Aceto Balsamico Tradizionale of Modena (ABTM; a traditional balsamic vinegar made from cooked grape must) is often difficult because of the presence of numerous interferences that need to be removed by separation techniques. To this aim, in the present work a solid-phase extraction (SPE) method with C18 and NH(2) exchangers was used to clean the ABTM samples prior to analysis or further treatments. Both HPLC and GC techniques were used to determine organic acids. The efficiency of these two different analytical techniques in the study of ABTM acidic composition has been evaluated. Both methods separately were not able to supply all the data related to carboxylic acids. In particular, HPLC allows acetic and lactic acids quantification, but gluconic and succinic acids are better determined by GC. As far as tartaric, citric, and malic acids are concerned, both HPLC and GC methods give statistically equivalent results. The variation of the single acidic species composition along a series of casks furnished interesting information regarding the chemical transformations taking place during the aging process of this product.  相似文献   
178.
Laboratory experiments were conducted using intact collembolan communities, exposed to Madit D®, a phenylurea herbicide (active ingredient isoproturon). Effects were investigated using two distinct humus types, an acid Dysmoder and a neutral Eumull. Within two weeks, no effect of the herbicide was displayed by the Eumull population, while the Dysmoder population was stimulated. When animals were able to escape from the herbicide through a perforated wall separating two compartments filled with natural soil, the behavior of collembolan communities exhibited interactive (non-additive) effects of humus type and herbicide application. The combination of an acid soil (supposedly providing greater tolerance to organic pollutants) with a neutral soil, increased biodiversity of Collembola, but caused the disappearance of some acido-sensitive species, pointing to complex relationships between pesticides, soils and soil organisms. Parallel experiments with single species demonstrated that at the recommended dose Madit D® may cause avoidance effects, but no toxicity.  相似文献   
179.
Neisseria meningitidis is a major cause of bacterial septicemia and meningitis. Sequence variation of surface-exposed proteins and cross-reactivity of the serogroup B capsular polysaccharide with human tissues have hampered efforts to develop a successful vaccine. To overcome these obstacles, the entire genome sequence of a virulent serogroup B strain (MC58) was used to identify vaccine candidates. A total of 350 candidate antigens were expressed in Escherichia coli, purified, and used to immunize mice. The sera allowed the identification of proteins that are surface exposed, that are conserved in sequence across a range of strains, and that induce a bactericidal antibody response, a property known to correlate with vaccine efficacy in humans.  相似文献   
180.
Polymeric alkylpyridinium salts (poly-APS) isolated from the Mediterranean marine sponge, Haliclona (Rhizoniera) sarai, effectively inhibit barnacle larva settlement and natural marine biofilm formation through a non-toxic and reversible mechanism. Potential use of poly-APS-like compounds as antifouling agents led to the chemical synthesis of monomeric and oligomeric 3-alkylpyridinium analogues. However, these are less efficient in settlement assays and have greater toxicity than the natural polymers. Recently, a new chemical synthesis method enabled the production of poly-APS analogues with antibacterial, antifungal and anti-acetylcholinesterase activities. The present study examines the antifouling properties and toxicity of six of these synthetic poly-APS using the barnacle (Amphibalanus amphitrite) as a model (cyprids and II stage nauplii larvae) in settlement, acute and sub-acute toxicity assays. Two compounds, APS8 and APS12-3, show antifouling effects very similar to natural poly-APS, with an anti-settlement effective concentration that inhibits 50% of the cyprid population settlement (EC50) after 24 h of 0.32 mg/L and 0.89 mg/L, respectively. The toxicity of APS8 is negligible, while APS12-3 is three-fold more toxic (24-h LC50: nauplii, 11.60 mg/L; cyprids, 61.13 mg/L) than natural poly-APS. This toxicity of APS12-3 towards nauplii is, however, 60-fold and 1200-fold lower than that of the common co-biocides, Zn- and Cu-pyrithione, respectively. Additionally, exposure to APS12-3 for 24 and 48 h inhibits the naupliar swimming ability with respective IC50 of 4.83 and 1.86 mg/L.  相似文献   
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