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971.
Daniel M Grove Anne M Zajac John Spahr Robert B Duncan Jonathan M Sleeman 《Journal of zoo and wildlife medicine》2005,36(1):111-114
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
972.
973.
Menzies-Gow NJ Bailey SR Stevens K Katz L Elliott J Marr CM 《American journal of veterinary research》2005,66(4):630-636
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
974.
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
975.
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
976.
Hayashi K Sicard G Gellasch K Frank JD Hardie RJ McAnulty JF 《Veterinary surgery : VS》2005,34(5):519-523
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
977.
Jonathan?M.?BossenbroekEmail author Helene?H.?Wagner John?A.?Wiens 《Landscape Ecology》2005,20(6):675-688
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
978.
Jonathan F. Bach DVM DACVIM DACVECC Orla M. Mahony DACVIM Amy S. Tidwell DVM DACVR John E. Rush DVM MS DACVIM DACVECC 《Journal of Veterinary Emergency and Critical Care》2007,17(4):409-415
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
979.
Anna Bolinder Kelly Cameron Lynn Faubert Jeff Wilson Jeff Aramini Jonathan Hare 《Canadian journal of veterinary research》2006,70(3):234-236
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
980.
Koenig JB Cote N LaMarre J Harris WH Trout DR Kenney DG Monteith G 《American journal of veterinary research》2002,63(11):1545-1550
OBJECTIVE: To identify and characterize motilin receptors in equine duodenum, jejunum, cecum, and large colon and to determine whether erythromycin lactobionate competes with porcine motilin for binding to these receptors. SAMPLE POPULATION: Specimens of various segments of the intestinal tracts of 4 adult horses euthanatized for reasons unrelated to gastrointestinal tract disease. PROCEDURE: Cellular membranes were prepared from smooth muscle tissues of the duodenum, jejunum, pelvic flexure, and cecum. Affinity and distribution of motilin binding on membrane preparations were determined by use of 125I-labeled synthetic porcine motilin. Displacement studies were used to investigate competition between 125I-labeled synthetic porcine motilin and erythromycin lactobionate for binding to motilin receptors in various segments of bowel. RESULTS: Affinity of 125I-labeled synthetic porcine motilin for the equine motilin receptor was estimated to be 6.1nM. A significantly higher number of motilin receptors was found in the duodenum than in the pelvic flexure and cecum. The jejunum had a significantly higher number of motilin receptors than the cecum. Erythromycin lactobionate displacement of 125I-labeled porcine motilin from the equine motilin receptor did not differ significantly among various segments of bowel. CONCLUSIONS AND CLINICAL RELEVANCE: Motilin receptors were found in the duodenum, jejunum, pelvic flexure, and cecum of horses. The highest number of motilin receptors was in the duodenum, and it decreased in more distal segments of bowel. Erythromycin lactobionate competed with motilin binding in the equine gastrointestinal tract. This suggests that 1 of the prokinetic actions of erythromycin in horses is likely to be secondary to binding on motilin receptors. 相似文献