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991.
An adult American crow (Corvus brachyrhynchos) from Virginia, USA, was diagnosed with combined infection of avian poxvirus and the skin fluke Collyriclum faba. The flukes and viral inclusions were combined in a large (4 x 4 cm) multilobulated proliferative mass on the ventrum just cranial to the cloaca. The flukes were identified using light microscopy of organisms obtained by antemortem wedge biopsy. Intraepithelial cytoplasmic inclusions consistent with poxvirus infection were seen on histopathologic examination of the mass.  相似文献   
992.
993.
OBJECTIVE: To measure plasma endothelin-1 (ET-1) concentrations and digital blood flow in clinically endotoxemic horses. ANIMALS: 36 adult horses that underwent emergency celiotomy for primary gastrointestinal tract disease. PROCEDURE: On days 2 and 5 following surgery, Doppler ultrasonographic digital arterial blood flow measurements were obtained. Hematologic and biochemical analyses were performed, and plasma concentrations of ET-1 and endotoxin (lipopolysaccharide) were determined. A scoring system based on 9 clinical variables was used to assign horses to group B (quartile with greatest cumulative score) or group A (remaining 3 quartiles). Follow-up at 2.5 years was obtained by telephone questionnaire. RESULTS: For all horses on day 2, median (interquartile values) plasma ET-1 concentrations were 1.4 (0.8, 1.7) pg/mL, whereas on day 5, plasma ET-1 concentrations were 1.0 (0.5, 1.6) pg/mL. On day 2, digital blood flow was 0.057 (0.02, 0.07) mL/min in group A horses and 0.035 (0.02, 0.03) mL/min in group B horses. On day 5, plasma ET-1 concentration was significantly (73%) higher in group B horses, compared with group A horses. Thirty of 36 horses were alive at 2.5 years; group A horses were more likely to have survived (odds ratio, 25; 95% confidence interval, 2.4 to 262). Significant associations were found between an increase in digital pulses, hoof wall temperatures, or both and increased digital blood flow (0.14 vs 0.04 mL/min) on day 2 and increased digital arterial diameter (0.32 vs 0.23 cm) on day 5. CONCLUSIONS AND CLINICAL RELEVANCE: Horses with more severe endotoxemia had decreased digital blood flow, increased plasma ET-1 concentrations, and decreased long-term survival.  相似文献   
994.
OBJECTIVE: To compare the outcome of horses with nephrosplenic entrapment of the large colon (NSELC) treated surgically or medically by rolling, administration of phenylephrine hydrochloride (or both), and exercise. DESIGN: Retrospective study. ANIMALS: 11 medically treated horses and 8 surgically treated horses with NSELC. PROCEDURE: Medical records of horses with nephrosplenic entrapment between 1992 and 2002 were reviewed. Medically treated horses were included if diagnosis and outcome of treatment of nephrosplenic entrapment were confirmed via transrectal examination and ultrasonographic examination. Surgically treated horses were included if the diagnosis was confirmed by exploratory laparotomy. Horses in which the large colon was entrapped between the spleen and body wall were not included. RESULTS: Significant differences in mean age, heart rate, and duration of colic prior to treatment were not detected between horses treated surgically or medically. Ten medically treated horses recovered without complications, and 1 died. In the surgically treated group, 6 of 8 horses recovered without complications and 2 died. Mortality rate did not differ between treatments. Duration of hospitalization for medically treated horses was significantly shorter and the cost significantly less than for surgically treated horses. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that medical treatment of horses with NSELC via administration of phenylephrine hydro-chloride, rolling during general anesthesia, or both appears to be as effective as and less expensive than surgical treatment.  相似文献   
995.
Hypertension is a common complication of canine hyperadrenocorticism. Increased pressor sensitivity to endogenous catecholamines is currently believed to be the main mechanism involved in the development of hypertension in human hyperadrenocorticism. The aim of this study was to evaluate pressor sensitivity to norepinephrine in dogs after induction of iatrogenic hyperadrenocorticism (I-HAC) by serial arterial blood pressure measurements during infusions of increasing dose rates of norepinephrine (0.1, 0.15, 0.2, 0.3, 0.4, 0.6, and 0.8 microg/kg/min) in eight dogs with I-HAC and eight control dogs. Systolic, diastolic, mean blood pressure and heart rate measurements were recorded. The changes in these parameters between the two groups of dogs were compared. Dogs in the I-HAC group had a more pronounced pressor response to norepinephrine infusions than control dogs since the infusions had to be stopped in seven of the dogs due to severe hypertension (>240 mmHg). The mean maximum tolerated dose rate in the control group was 0.6 microg/kg/min with a standard error of 0.0 and 0.34 microg/kg/min with a standard error of 0.08 in the I-HAC group. The study demonstrated the presence of increased pressor sensitivity to norepinephrine in dogs with I-HAC.  相似文献   
996.
OBJECTIVE: To report use of combined cisterna chyli ablation (CCA) and thoracic duct ligation (TDL) for treatment of spontaneously occurring chylothorax in dogs. STUDY DESIGN: Retrospective study. ANIMALS: Eight dogs with chylothorax. METHODS: TDL was performed through a right caudal intercostal thoracotomy and CCA through a left flank paracostal approach or ventral median celiotomy. Long-term outcome (range, 2-48 months; median, 11.5 months) was evaluated by telephone communication with owners. RESULTS: Seven dogs were free of clinical signs related to chylothorax at last follow-up (range, 4-48 months; median, 15.5 months). One dog was euthanatized 2 months after surgery because of lack of improvement. No major complications occurred from CCA. CONCLUSION: CCA and TDL resolved chylothorax in most dogs (88%). CLINICAL RELEVANCE: CCA combined with TDL may improve the outcome of chylothorax in dogs.  相似文献   
997.
Because organisms respond to the environment at different scales, it is important to develop ways of determining the appropriate scales for a specific ecological process and organism. We consider whether the relative importance of different scales is associated with organism mobility, and whether this relationship is independent of landscape characteristics. We observed abundances of particular species for vascular plants, ground-dwelling beetles and breeding birds along eight 2-km transects of 40 sampling stations each, distributed over four sites along the regional gradient from shortgrass steppe in central Colorado to tallgrass prairie in central Kansas. For each transect and taxonomic group, the relative importance of factors measured at the trap scale (1 m; soil texture and hardness, vegetation height, bare ground), at the local scale (10 m; density of shrubs and cacti) and at the landscape scale (30 m; Landsat 7 TM spectral bands, slope and elevation) was assessed using hierarchical canonical variance partitioning with forward selection of explanatory variables. Plant, beetle and bird community composition was explained by environmental factors measured at all three scales. Factor influence was more consistent between transects and between plants and beetles for the more homogeneous landscapes of the shortgrass steppe than for the more heterogeneous landscapes of the tallgrass prairie. We conclude that, independent of the mobility of a taxonomic group, factors at several scales are important in explaining community composition. The importance of different scales shifts along a regional gradient, and the variability between sites is high even for nearby sites.  相似文献   
998.
Objective: To describe a case of multifocal brain abscessation as a sequela from bacterial endocarditis in a dog with a 4‐month history of immune‐mediated thrombocytopenia (ITP) and treatment with immunosuppressive therapies. Case summary: An 8‐year‐old spayed female Kerry Blue Terrier weighing 13 kg was presented for evaluation of progressive neurologic deficits after a 4‐month history of immunosuppressive treatment of ITP. Brain magnetic resonance imaging revealed lesions consistent with multiple central nervous system abscesses and rupture of an abscess into an adjacent ventricle. Staphylococcus species were cultured from blood and cerebral spinal fluid and a vegetative lesion of the mitral valve was identified by echocardiographic examination. Intensive care, intravenous antibiotics, and supportive therapy led to resolution of clinical signs. Resolution of the vegetative lesion on the mitral valve was documented by serial echocardiographic examination. The dog was clinically normal 11 months after treatment. New or unique information provided: Bacterial endocarditis can be an occult infection and difficult to diagnose. Emboli from endocarditis are common, but those that affect the spleen and kidneys are often clinically silent in dogs. This case represents the first report of multifocal brain abscessation (documented with magnetic resonance imaging) as a sequela from bacterial endocarditis.  相似文献   
999.
This study evaluated the anti-inflammatory properties of Surolan with the use of a pinna model of inflammation in 80 mice and a randomized complete block design. Within each of 8 blocks, 10 treatments, consisting of different combinations of the constituents of Surolan with and without the prednisolone acetate component, were randomly assigned to the 9-wk-old CD-1 mice. The treatments were administered as a single dose 30 min after pinna inflammation was induced with tetradecanoylphorbol acetate. Ear-skin edema and erythema were assessed and measured 4 and 6 h thereafter. Treatment effects were evaluated with repeated-measures analysis of variance. Inclusion of prednisolone acetate with the Surolan vehicle, either alone or in combination with the nonsteroidal constituents of the suspension, resulted in a significant reduction in mean ear-skin thickness and erythema. The inflammation-reducing properties of prednisolone were not significantly affected by the other components of Surolan.  相似文献   
1000.
Lurz  P.W.W.  Rushton  S.P.  Wauters  L.A.  Bertolino  S.  Currado  I.  Mazzoglio  P.  Shirley  M.D.F. 《Landscape Ecology》2001,16(5):407-420
There is growing concern about the spread of the North American grey squirrel (Sciurus carolinensis) in northern Italy which were introduced into Piedmont in 1948. They have since spread across the Po-plain covering an area of approximately 450 km2 and continue to expand their range. In parallel to what has been observed in Britain and Ireland, grey squirrels replace the native red squirrel (S. vulgaris) and damage poplar (Populus) plantations through bark-stripping. Spatially explicit population dynamics models have been successfully used to predict the spread of grey squirrels in East Anglia, England. We extended a previous approach employing a sensitivity analysis where life history and other demographic inputs are generated using Latin Hypercube Sampling from the known ranges of each input parameter, and applied it to Italy using field data collected in Piedmont. The analysis indicated that reproductive output was the most important factor determining total population size present in Piedmont. The structure and composition of woodland habitats around the introduction site suggested that initial grey squirrel expansion would have been slow and subject to emigration rates from the available habitat blocks.A comparison of the 1996 survey results with model predictions indicated that a mean litter size of three young gave the best fit with the observed distribution and we use this to predict future grey squirrel spread. We also present a worst case scenario in which grey squirrels experience improved reproductive success due to the availability of high quality habitats beyond the Po plain. In both cases they could disperse along existing continuous woodland corridors into France between 2039–2048. The case of the grey squirrel highlights the problems of implementing conservation conventions and the resulting conflicts between wildlife management, public perception and local political support and the narrow time frame that is available to control alien species effectively before it is too late. If allowed to spread, grey squirrels have the potential of becoming a European forest pest species and are likely to replace the native red squirrel in large parts of its range.  相似文献   
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