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31.
Richardson JA Gwaltney-Brant SM Albretsen JC Khan SA Porter JA 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2002,16(2):208-210
Zolpidem is a nonbenzodiazepine hypnotic of the imidazopyridine class that is used to treat insomnia in humans. Zolpidem binds selectively to the benzodiazepine omega-1 receptor and increases the frequency of chloride channel opening, which results in inhibition of neuronal excitation. A retrospective study was conducted of zolpidem ingestion in dogs that were reported to the ASPCA Animal Poison Control Center (APCC) between January 1998 and July 2000. Data analysis included amount ingested, clinical effects, and time of onset of signs. Thirty-three reports of zolpidem ingestion in dogs (ranging in age from 5 months to 16 years) were evaluated. Approximate ingested dosages ranged from 0.24 to 21 mg/kg. Clinical signs reported included ataxia (18 dogs; 54.5%), hyperactivity (10 dogs; 30.3%), vomiting (7 dogs; 21.2%), and lethargy (5 dogs; 15.2%), as well as panting, disorientation, nonspecific behavior disorder, and hypersalivation (4 dogs each sign; 12.1%). Other signs reported include tachycardia, tremors, apprehension, vocalization, hypersalivation, weakness, and hyperesthesia. In 85% percent of reports, clinical signs developed within 1 hour and usually resolved within 12 hours. Although central nervous system (CNS) depression is reported as a primary effect of zolpidem in humans and would also be expected in dogs, information obtained from this study indicates that some dogs may exhibit a paradoxical excitation reaction. This effect appears to vary among individual dogs. 相似文献
32.
A 9-year-old Labrador Retriever was diagnosed with ganglioradiculitis (sensory neuronopathy). This idiopathic disease of mature dogs is characterized by a profound loss of sensory nerve function due to mononuclear inflammatory infiltration of peripheral ganglia and spinal nerve roots, with destruction of sensory neurons. Immunohistochemistry demonstrates that the infiltrating cells are primarily T lymphocytes and that immunoglobulins are not present on the cell membranes of affected neurons. The pathogenesis of ganglioradiculitis remains unclear, but the evidence points to a cell-mediated immune mechanism. 相似文献
33.
Kathy N. Wright DVM Dipl. ACVIM Timothy K. Knilans MD Holly M. Irvin 《Journal of Veterinary Cardiology》2006,8(2):95-107
Radiofrequency catheter ablative techniques provide a unique opportunity to cure dogs of certain supraventricular tachyarrhythmias, rather than simply controlling the rhythm with drug therapy. Accessory pathways, which can participate as one limb of a rapid, narrow complex tachyarrhythmia circuit, have a particularly high cure rate with radiofrequency catheter ablation. Focal atrial tachycardias also provide a substrate that can be amenable to ablation. Tachycardia-induced myocardial dysfunction resulting from frequent tachyarrhythmic episodes will resolve after a successful ablation. This report outlines the indications, equipment, and techniques used in dogs for performing catheter ablation with temperature-controlled radiofrequency energy delivery. 相似文献
34.
ZÜLFIKAR SARITAS PhD DVM ERDOGAN SAMSAR DVM PERRAN GÖKGE DVM S. FEHMI KATIRCIOGLU MD 《Veterinary surgery : VS》1998,27(4):378-383
Objective—To compare enoximone with epinephrine as treatments for the cardiotoxic effects of protamine sulfate.
Study Design—Prospective randomized study.
Animal Population—12 healthy cross-bred dogs weighing 23 ± 4 kg.
Methods—The dogs were anesthetized with xylazine and ketamine to allow instrumentation. Femoral arterial and venous catheters were inserted for pressure monitoring and to allow drug infusion. A thermodilution catheter mounted with a fast response thermistor was inserted into the pulmonary artery via the jugular vein to measure cardiac output and right ventricular volumes. Heparin 300 units/kg followed by protamine 4.5 mg/kg were administered 45 minutes after the xylazine/ketamine. Four animals were not treated (controls), four received enoximone, and four were given epinephrine. Cardiopulmonary parameters were monitored for a period of 30 minutes.
Results—Cardiac index was 104 ± 15 mL/kg/min in the enoximone group, 72 ± 13 mL/kg/ min in the epinephrine group, and 63 ± 10 mL/kg/min in the control group ( P < .05 enoximone versus control and epinephrine). Right ventricular end systolic volume was 18 ± 3, 27 ± 4, and 29 ± 6 mL in the enoximone, epinephrine, and control groups ( P < .05 enoximone versus control and epinephrine). There were no differences in mean arterial pressure or pulmonary and systemic vascular resistance between the groups.
Conclusions and Clinical Relevance—In this study, enoximone was more effective than epinephrine at reversing the hemodynamic changes associated with protamine sulfate administration. 相似文献
Study Design—Prospective randomized study.
Animal Population—12 healthy cross-bred dogs weighing 23 ± 4 kg.
Methods—The dogs were anesthetized with xylazine and ketamine to allow instrumentation. Femoral arterial and venous catheters were inserted for pressure monitoring and to allow drug infusion. A thermodilution catheter mounted with a fast response thermistor was inserted into the pulmonary artery via the jugular vein to measure cardiac output and right ventricular volumes. Heparin 300 units/kg followed by protamine 4.5 mg/kg were administered 45 minutes after the xylazine/ketamine. Four animals were not treated (controls), four received enoximone, and four were given epinephrine. Cardiopulmonary parameters were monitored for a period of 30 minutes.
Results—Cardiac index was 104 ± 15 mL/kg/min in the enoximone group, 72 ± 13 mL/kg/ min in the epinephrine group, and 63 ± 10 mL/kg/min in the control group ( P < .05 enoximone versus control and epinephrine). Right ventricular end systolic volume was 18 ± 3, 27 ± 4, and 29 ± 6 mL in the enoximone, epinephrine, and control groups ( P < .05 enoximone versus control and epinephrine). There were no differences in mean arterial pressure or pulmonary and systemic vascular resistance between the groups.
Conclusions and Clinical Relevance—In this study, enoximone was more effective than epinephrine at reversing the hemodynamic changes associated with protamine sulfate administration. 相似文献
35.
Debra K. Baird DVM John T. Hathcock DVM MS Steven A. Kincaid DVM MS PhD Paul F. Rumph DVM MS John Kammermann MS William R. Widmer DVM MS Denise Visco PhD Donald Sweet MD 《Veterinary radiology & ultrasound》1998,39(3):167-173
Six healthy adult male mongrel dogs underwent cranial cruciate ligament transection in the left stifle. Survey radiography of both stifles and low-field (0.064 T) MRI of the left stifle were performed preoperatively and at 2, 6, and 12 weeks postoperatively. Focal changes in signal intensity were seen with MRI in the subchondral bone of the medial tibial condyle at 2 and 6 weeks postoperatively. At 12 weeks postoperative, a cyst-like lesion was detected using MRI in the subchondral bone of the medial tibial condyle in 4 of 6 dogs and a less defined lesion at this site in the remaining 2 dogs. The cyst-like lesion was spherical in shape and showed typical characteristics of fluid with low signal intensity on T1-weighted images, high signal intensity on T2-weighted images and high signal intensity on inversion recovery images. The lesion was seen in the subchondral bone of the caudal medial and/or middle region of the tibial plateau slightly cranial to the insertion of the caudal cruciate ligament. No subchondral cysts were seen in the tibia on radiographs. Histopathologically, the tibia was characterized by a loose myxomatous phase of early subchondral cyst formation. 相似文献
36.
Piper L. Wall DVM PhD † Akella Chendrasekhar MD †Gregory A. Timberlake MD † 《Journal of Veterinary Emergency and Critical Care》1998,8(2):109-115
The accuracy and precision of an end-tidal infrared CO2 monitor and customized capnography tubing system designed to measure gastrointestinal intraluminal CO2 partial pressure (Pi CO2 ) were tested in vitro. Samples were taken from the customized capnography tubing placed in either 5% or 10% CO2 gas at discrete intervals ranging from one minute to twelve minutes. For a given time interval, the tubing PCO2 measurement was a constant fraction of the actual PCO2 (all standard errors < 0.02). For increasing time intervals, the ratio of the tubing PCO2 to actual PCO2 increased logarithmically. In the 5% and 10% CO2 , the regression coefficients were 0.89 and 0.85 for 8 French tubing and 0.99 and 0.91 for 6 French tubing. Beacuase of its accuracy and precision, this system may provide automated gastrointestinal CO2 partial pressure monitoring at short intervals (e.g. 5 minutes), facilitating testing of the role of gastrointestinal Pi CO2 information in treatment algorithms. (Vet Emerg & Crit Care, 1998; 8: 109–116) 相似文献
37.
Foliar fertilizers (FF) applied at the reproductive growth stage was reported to increase soybean (Glycine max L. Merr.) yield in field trials. But yield increases have not been consistent. Field experiments were conducted on Calloway silt loam soil in 1981—1982 to determine the effect of two foliar fertilizer (FF) formulations, 16N + 4P + 4K + 1 S (Hanway) and 12 N + 4 P + 4 K + 0.5 S (Folian), and time of application, 0800- and 1900-h, on the growth of seven soybean cultivars from maturity groups V, VI, and VII. Foliar fertilizers were applied at a rate of 187 L/ha?1 in water by a backpack CO2 pressure sprayer at R5 to R6 growth stages. Foliar fertilizers caused no crop injury (leaf burn) when applied at 1900-h but caused moderate injury at 0800-h, which caused a yield reduction. The most significant crop injury was caused by Hanway formulation when applied at 0800-h. Yields were significantly reduced by FF in 1981 but not in 1982. Generally, Folian formulation treatments had higher yields than Hanway formulation treatments, but neither formulation increased yield above that of the untreated plants. The Bragg cultivar exhibited the least amount of crop injury and the most positive yield response to FF. Plant height, 100-seed weight and lodging rates were not adversely affected by the foliar applications. Due to the general lack of consistent yield increases or in some instances yield reduction from FF applications, the formulations used cannot be recommended for use by soybean producers. 相似文献
38.
Angular deformities of 25 or 37 degrees valgus were created by transverse wedge osteotomies in the diaphysis of the radius in 3-month-old Cocker Spaniels. Spontaneous correction was judged from radiographs until skeletal maturity. The magnitude of correction was estimated, using the opposite normal leg as a control. Asymmetrical physeal growth corrected the induced angulation between the proximal and distal radial joint plane surfaces (joint plane angle). The average correction of the joint plane angle was 80% in the 25 degree group, and 72% in the 37 degree group. Bone remodeling of the radial shaft corrected the induced diaphyseal angulation by 50% in both groups during the study. 相似文献
39.
40.
Studies on canine pregnancy using B-mode ultrasound: Development of the conceptus and determination of gestational age 总被引:3,自引:0,他引:3
G.C.W. England W. Edward Allen D. J. Porter 《The Journal of small animal practice》1990,31(7):324-329
Development of the conceptus was characterised using B-mode ultrasound in a standard size of dog (labrador retrievers, golden retrievers and their crosses; weight range 22 to 30 kg). Growth curves were established for various measurements of the conceptuses. Regression equations allowed the prediction of the expected time of parturition. Multiple regression analysis of two measurements (biparietal diameter and trunk diameter) resulted in an increase in the confidence of prediction. 相似文献