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601.
602.

Objective

To compare the topographic modifications and tactile sensitivity of the pharynx and larynx after administration of four sedative and analgesic protocols in standing horses.

Study design

Experimental, observer-blinded, crossover study.

Animals

Eight healthy mares.

Methods

Five protocols were evaluated: 1) xylazine and butorphanol administered intravenously (IV); 2) detomidine and butorphanol administered IV; 3) xylazine administered IV and lidocaine topically; 4) detomidine administered IV and lidocaine topically and 5) no analgesia or sedation (control). Quality of sedation, head height and sudden head movements were recorded. The degree of arytenoid cartilage displacement, the degree of pharyngeal collapse and the occurrence of soft palate displacement were scored using standardized scales. Tactile sensitivity was tested on 10 different pharyngeal and laryngeal regions using an atraumatic transendoscopic probe. Statistical analysis was performed using linear or generalized mixed-effects models.

Results

Head height was significantly decreased in protocols with xylazine (p = 0.002). Head movements were significantly increased in protocols with butorphanol (p = 0.0001). No changes in abduction grade or degree of soft palate displacement were observed between all sedative protocols and the control group. Pharyngeal collapse was significantly more frequent in protocols with lidocaine (p < 0.001) or xylazine (p = 0.017). For the pharyngeal regions, no tactile sensitivity difference was observed between the control and treatment protocols. All treatment protocols led to greater desensitization of all the laryngeal regions compared with the control protocol.

Conclusion and clinical relevance

All the protocols provided adequate sedation and analgesia for the manipulation of the larynx and pharynx but significant differences were noted. Xylazine produces a more profound sedation compared with detomidine, but can induce dorsal pharyngeal collapse. Lidocaine caused pharyngeal collapse and its use should be limited to the target area. Butorphanol can be added to improve analgesia in the other regions but frequent head jerking can be expected.  相似文献   
603.
Jaagsiekte Sheep Retrovirus (JSRV) is a betaretrovirus infecting sheep. This virus is responsible for a pulmonary adenocarcinoma, by transformation of epithelial cells from the bronchioli and alveoli. This animal cancer is similar to human bronchioloalveolar cancer (BAC), a specific form of human lung cancer for which a viral aetiology has not yet been identified. JSRV interacts with target cells through the membrane receptor Hyal2. The JSRV genome is simple and contains no recognised oncogene. It is now well established that the viral envelope protein is oncogenic by itself, via the cytoplasmic domain of the transmembrane glycoprotein and some domains of the surface glycoprotein. Activation of the PI3K/Akt and MAPK pathways participates in the envelope-induced transformation. Tumour development is associated with telomerase activation. This review will focus on the induction of cancer by JSRV.  相似文献   
604.
OBJECTIVE: To investigate the frequency of bacterial contamination of multidose proparacaine hydrochloride, tropicamide, and eyewash bottles used in veterinary ophthalmology examination rooms during normal operating procedures. METHODS: Three representative bottles each of proparacaine hydrochloride, tropicamide, and purified water eye wash were opened at the same time, numbered, and placed into small animal examination rooms. Doctors, students and technicians who were using the solutions were blinded to the study. Aerobic cultures were obtained at the time of opening (time 0), at 1 week (time 1), and at 2 weeks after opening (time 2) the bottles. The sites cultured included a drop of each solution, the inside of the bottle cap, the tip of the bottle, and the bottle threads and medication residue found in these threads. RESULTS: Aerobic cultures of tropicamide and proparacaine had no growth of bacteria from any of the evaluated sites. Staphylococcus epidermidis was cultured from the tip of one bottle of eye wash after 1 week. CONCLUSIONS: We conclude that proparacaine, tropicamide, and eyewash solutions used in veterinary examination rooms are adequately preserved for use in ophthalmic examination. They have a low level of bacterial contamination 1 or 2 weeks after opening when used and stored according to the recommendations of the product manufacturers and previous studies.  相似文献   
605.
Canine distemper is a highly contagious disease with high incidence and lethality in the canine population. The objective of this study was to evaluate the efficacy of antiviral action with ribavirin (RBV), interferon-alpha (IFNα), and combinations of RBV and IFNα against canine distemper virus (CDV). Vero cells inoculated with CDV were treated with RBV, IFNα, and combinations of these drugs. The efficacy to inhibit viral replication was evaluated by adding the compounds at different times to determine which step of the viral replicative process was affected. Both drugs were effective against CDV in vitro. The IFNα was the most active compound, with an average IC50 (50% inhibitory concentration) value lower than the IC50 of the RBV. Ribavirin (RBV) was more selective than IFNα, however, and neither drug showed extracellular antiviral activity. The combination of RBV and IFNα exhibited antiviral activity for the intra- and extracellular stages of the replicative cycle of CDV, although the intracellular viral inhibition was higher. Both RBV and IFNα showed high antiviral efficacy against CDV, and furthermore, RBV + IFNα combinations have shown greater interference range in viral infectivity. These compounds could potentially be used to treat clinical disease associated with CDV infection.  相似文献   
606.
Goal, Scope and Background  Temperature and soil moisture content are important environmental variables in bioremediation technologies. Optimizing these variables in-situ would enhance and maintain remediation of hazardous wastes during cold winter seasons or in cold regions and may lead to reduced maintenance and/or cost. The effect of elevated temperature and soil moisture on bioremediation efficiency was investigated using a laboratory mesocosm approach. Selected polycyclic aromatic hydrocarbons (PAHs) and phenols degradation in contaminated flooded soils, commonly found in Superfund sites situated in coastal plains sediments/soils, were evaluated in the mesocosms. Material and Methods  Four laboratory mesocosm treatments in triplicate simulating in-situ bioremediation of contaminated site soils using an immobilized microbe bioreactor system, i.e., bioplug, were established to evaluate temperature effects. Elevated temperature treatments of site soils with and without contaminant-specific microorganisms were established at a temperature of 42±2°C. Similarly, treatment of site soils with and without contaminant-specific microorganisms were established at an ambient temperature of 21±1°C. Composite samples were analyzed for selected PAHs and chlorinated phenols to determine rates of mineralization and overall remediation efficiency for different temperature regimes. Results  Mesocosm studies indicated that the high temperature inoculated treatment demonstrated a significant reduction in mean total PAHs and total phenols with a kinetic rate (KR) of 76±13 ng g−1 d−1 in 49 days (approximately 84% reduction; p<0.01) The KR for low temperature inoculated treatment was 54±1 ng g−1 d−1 in 49 days (approximately 66% reduction; p<0.01). High temperature non-inoculated mesocosms exhibited significant mineralization of all constituents with KR of 15±6 ng g−1 d−1 (approximately 65% reduction; p<0.01) in 49d compared to 54% reduction for low temperature non-inoculated treatment with KR of 12±3 ng g−1 d−1 (p=0.1794). Phenol compounds in inoculated treatments were also significantly reduced (65%, p<0.01) at elevated temperatures compared to ambient (52%, p<0.01). Discussion  Increased bioavailability and desorption were noted for elevated temperature and moisture in the soil laboratory mesocosms simulating a field in situ remediation protocol. This protocol employing the application of immobilized microflora indicated that in situ systems provide an economical advantage if optimal elevated temperature and moisture are controlled properly. Results also suggested that temperature and moisture optimization needs to be combined with efficient nutrients delivery systems for impacted soils/sediments. Conclusions  The study demonstrated that temperature and soil moisture contents are important factors in the success of in-situ bioremediation techniques at hazardous waste sites situated in a coastal zone. Kinetic rates were significantly enhanced to remediate known recalcitrant compounds (PAHs and phenols) in aged soil. Recommendations and Perspectives  The placement of a preferred microbial consortia such as an immobilized microbial population in an entrained bioreactor, i.e., bioplug, can significantly reduce constituents of concern in a timely manner for contaminated soils/sediments. However, frequent monitoring of the soil temperature, moisture content, nutrient level, and dissolved oxygen is necessary to achieve predictable kinetic rates of mineralization. ESS-Submission Editor: Dr. Teresa Cutright (tcutright@uakron.edu)  相似文献   
607.
We report relative abundances and distributions of land bird communities on eight isolated islands of the Tuamotu Archipelago (Polynesia, South Pacific Ocean) during two 21-day expeditions in 1999. The selection of islands was based on the historical range of the Polynesian ground-dove (Gallicolumba erythroptera), in the hope of finding populations of this critically endangered species. Data were also collected on the Tuamotu sandpiper Prosobonia cancellata, the Atoll Fruit-dove Ptilinopus coralensis, the Tuamotu reed-warbler Acrocephalus atyphus, the Spotless Crake Porzana tabuensis and the Bristle-thighed Curlew Numenius tahitiensis, and on introduced predators (cats, rats, pigs and dogs). None of the five land-bird species recorded previously, in 1922 and 1974, has completely disappeared, but ranges of several species have contracted. Only one population of G. erythroptera erythroptera was found and it is the only population known for this species today. Our data also raise particular concern for the future of the Tuamotu sandpiper.  相似文献   
608.
The flavor of eight cocoa liquors of different origins (Africa, America, and Asia) and different varieties (Fine grades: criollo, trinitario, and nacional. Bulk-basic grade: forastero.) was analyzed by headspace solid-phase microextraction mass spectrometry (HS-SPME-MS). Their procyanidin contents were quantified by HPLC-UV (280 nm). Fine varieties with short fermentation processes proved to contain more procyanidins, while criollo from New Guinea and forastero beans showed the highest aroma levels. The levels of cocoa aroma compounds formed during roasting are shown to vary directly with bean fermentation time and inversely with residual procyanidin content in cocoa liquor. Measurement of antioxidant activity in cocoa liquor proved to be a useful tool for assessing residual polyphenols.  相似文献   
609.
We recently showed that dietary supplementation with key functional amino acids (FAA) improves growth performance and immune status of Salmonella Typhimurium (ST)-challenged pigs. It is not known if ST-challenged pigs will benefit from a longer adaptation period to FAA. The objective of this study was to evaluate the effects of different adaptation periods to diets containing FAA above requirements for growth on performance and immune response of weaned pigs subsequently challenged with ST. A total of 32 mixed-sex weanling pigs (11.6 ± 0.3 kg) were randomly assigned to 1 of 4 dietary treatments, being a basal amino acid (AA) profile fed throughout the experimental period (FAA−) or a functional AA profile (FAA+; Thr, Met, and Trp at 120% of requirements) fed only in the postinoculation (FAA+0), for 1 wk pre- and postinoculation (FAA+1), or throughout the experimental period (FAA+2). After a 14-d adaptation period, pigs were inoculated with ST (2.15 × 109 CFU/mL). Growth performance, body temperature, fecal score, acute-phase proteins, oxidant/antioxidant balance, score for ST shedding in feces and intestinal colonization, and fecal and digesta myeloperoxidase (MPO) were measured pre- and postinoculation. Postinoculation body temperature and fecal score, serum haptoglobin, plasma superoxide dismutase (SOD), malondialdehyde (MDA), and fecal MPO were increased while serum albumin and plasma reduced glutathione (GSH):oxidized glutathione (GSSG) were reduced compared to pre-inoculation (P < 0.05). Average daily gain and G:F were greater in FAA+2 pigs compared to FAA− pigs (P < 0.05). Serum albumin was higher in FAA+2 and FAA+1 compared to FAA+0 and FAA− pigs (P < 0.05) while FAA+2 pigs had lower haptoglobin compared to FAA− (P < 0.05). Plasma SOD was increased and GSH:GSSG was decreased in FAA− pigs compared to the other treatments (P < 0.05). Score for ST shedding in feces was progressively lower from d 1 to 6 regardless of treatment (P < 0.05) and was lower in FAA+2 pigs compared to FAA− and FAA+0 (P < 0.05). Counts of ST in colon digesta were higher in FAA− and FAA+0 pigs compared to FAA+2 (P < 0.05). Fecal and colonic digesta MPO were lower in FAA+2 and FAA+1 pigs compared to FAA− (P < 0.05). These results demonstrate a positive effect of a longer adaptation period to FAA-supplemented diets on performance and immune status of weaned pigs challenged with Salmonella.  相似文献   
610.
OBJECTIVE: To study changes in lifestyle in relation to changes in body weight and waist circumference associated with occupational retirement in men. DESIGN: A prospective cohort study with 5 years of follow-up. At baseline and at follow-up, questionnaires were completed and body weight and waist circumference were measured. SETTING: The Doetinchem Cohort Study, consisting of inhabitants of Doetinchem, a town in a rural area of The Netherlands.Subjects: In total 288 healthy men aged 50-65 years at baseline, who either remained employed or retired over follow-up. RESULTS: The effect of retirement on changes in weight and waist circumference was dependent on type of former occupation. Increase in body weight and waist circumference was higher among men who retired from active jobs (0.42 kg year(-1) and 0.77 cm year(-1), respectively) than among men who retired from sedentary jobs (0.08 kg year(-1) and 0.23 cm year(-1), respectively). Weight gain and increase in waist circumference were associated with a decrease in fruit consumption and fibre density of the diet, with an increase in frequency of eating breakfast, and with a decrease in several physical activities, such as household activities, bicycling, walking and doing odd jobs. CONCLUSION: Retirement was associated with an increase in weight and waist circumference among those with former active jobs, but not among those with former sedentary jobs. Retirement may bring opportunities for healthy changes in diet and physical activity, which could be used in health promotion programmes.  相似文献   
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