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81.
Fusarium head blight (FHB) has emerged as a major threat to wheat crops around the world, and it has been hypothesized that wheat antioxidants may play a role against Fusarium infections. The current study aimed to determine antioxidant properties of FHB-resistant wheat grains as compared to susceptible wheat. The wheat samples were collected from a single growing location (Warsaw, VA) and the same growing season. The results showed that both FHB-resistant and -susceptible wheat grains exerted strong radical scavenging activities against DPPH* radical [0.91-1.53 micromol of Trolox equivalents (TE)/g], peroxyl radical (15.5-24.5 micromol of TE/g), and hydroxyl radical (15.7-35.8 micromol of TE/g). Their total phenolic contents ranged from 888 to 1117 microg of gallic acid equivalents (GAE)/g. Five phenolic acids including ferulic, syringic, vanillic, caffeic, and p-coumaric acids were determined in soluble and insoluble fractions of wheat grains, altogether with a range of 219-389 microg/g. On average, the FHB-resistant wheat group showed significantly higher average values in DPPH* and hydroxyl radicals scavenging activities (30 and 41% higher, respectively) than the FHB-susceptible wheat group.  相似文献   
82.
83.
This paper describes a primary extraskeletal osteogenic sarcoma arising in the spleen of an 11-year-old, male, cross-bred Terrier. Initial diagnosis was made after surgical removal of a splenic mass, at which time the liver and other abdominal viscera appeared grossly normal. However, elevations in the activities of alanine aminotransferase and alkaline phosphatase in blood taken 7 days after laparotomy suggested that hepatic metastases were developing. This was confirmed when the dog died 3.5 months after surgery, with massive hepatic metastatic involvement. There appears to be no previous report of the spleen being the primary site of such a neoplasm in the dog.  相似文献   
84.
Biomechanical analysis was performed on the cranial cruciate ligament (CCL) and three autogenous tissues used for CCL reconstruction in the canine stifle. The autogenous tissues were patellar ligament-based autografts described for over-the-top CCL replacement and included the central one third of the patellar ligament, the medial one third of the patellar ligament, and the lateral one third of the patellar ligament with fascia lata. Tension testing produced abrupt failure of the central and medial autografts but sequential failure of the lateral autograft. Structural properties were determined for the overload condition and within the load range of normal activity for the CCL (physiologic range). None of the autograft systems approached the stiffness, maximum load, and energy absorbed to maximum load of the CCL. The central and lateral autografts were stiffer, had greater maximum loads, and absorbed more energy to maximum load than the medial autograft. The central and lateral autografts had an elastic range, as defined by proportional limit, which corresponded to the physiologic range of loading for the CCL. Loads that corresponded to physiologic displacement of the lateral and central autografts were near the maximum load of the fixation site, which underscored the need for postoperative support of the repaired stifle.  相似文献   
85.
The effect of commonly used sedatives on gastrointestinal motility and transit time in cats was evaluated using barium sulfate in gastrointestinal contrast studies. Control studies were performed in nonsedated animals, and the results were compared with those obtained from each of five sedation studies (ANOVA; p < 0.05). The ketamine/acepromazine transit time (18 minutes) was shortened significantly compared with the control group (42 minutes), and both ketamine/acepromazine and ketamine alone resulted in significant increase in the number of gastric contractions. The level of sedation was evaluated subjectively and compared with the transit times to determine a chemical restraint method for potential clinical use that would have the least effect on transit time and motility yet provide adequate sedation. When sedation is necessary and motility is not a primary concern, the ketamine/acepromazine combination if recommended. If a gastrointestinal motility problem is suspected, the ketamine/valium combination should be used.  相似文献   
86.
Lupinosis was produced in sheep in four experiments by administering a toxic extract of Phomopsis leptostromiformis by various routes and at various dose rates. The course of the intoxication was followed by plasma biochemical analyses for a number of electrolytes, metabolites and enzymes. Results from these analyses suggested that in addition to being an hepatotoxicity, lupinosis also resulted in injury to muscle, kidney and adrenal cortex. This was confirmed by microscopic examination of these tissues.  相似文献   
87.
A 10-year-old Toy Poodle was admitted for evaluation of a chronic cough caused by a cranial mediastinal mass. The mass was diagnosed, by needle biopsy, as a thymoma. Detection of serum acetylcholine receptor antibodies suggested that the dog had subclinical myasthenia gravis. The dog underwent orthovoltage radiation treatment, which resulted in an approximate 60% reduction in tumor mass and freedom from clinical signs for 6 months. Concurrent use of prednisolone may have been associated with disappearance of the acetylcholine receptor antibodies.  相似文献   
88.
AIMS: Canine and feline uroliths were analysed to determine the prevalence of particular types of urolith and the dog breeds at risk. METHODS: Three hundred and sixty-nine uroliths recovered from 316 dogs and 53 cats between November 1993 and December 1996 were analysed by X-ray diffraction, and by infrared spectrometry where X-ray diffraction alone was non-diagnostic. RESULTS: Bitches of small breeds especially Welsh corgi and Bichon frise, were most frequently affected. Struvite was the most common urolith (204 dogs). Oxalate (60 dogs) was the second most prevalent urolith identified, followed by cystine (24 dogs). The breeds producing cystine calculi were: Dalmatian, Bassett hound, Borzoi, Newfoundland, Shetland sheepdog, Labrador, Chihuahua, Fox terrier, English bulldog, Bichon frise, Doberman pinscher, Border collie. Silica uroliths were identified for the first time in New Zealand. All feline uroliths were struvite. CONCLUSION: The results are useful in determining the prevalence of specific types of urolith in New Zealand and the breeds at risk of forming them.  相似文献   
89.
Redox behavior of nitrofen (2,6-dichlorophenyl-p-nitrophenyl ether) at a glassy carbon working electrode in aprotic and protolytic solvents was examined using cyclic voltammetry. The electrode reaction of 2 mM nitrofen in dimethylformamide (0.1 M tetra-n-butylammonium hexafluorophosphate as supporting electrolyte) was quasireversible. Measured half-wave potential was ?1.11 V vs saturated calomel reference electrode (SCE) and peak potential separation was 0.110 V. The reduction product was chemically stable on the time scale of the experiment; cathodic peak current equalled anodic peak current. Linear sweep voltammetry employing a rotating, glassy carbon disk electrode indicated that electron stoichiometry for reduction of nitrofen in dimethylformamide and acetonitrile was one. Reduction of nitrofen under aprotic conditions was most likely a one-electron reduction to the nitro radical anion. Reduction of 1 mM nitrofen in 50% (vv) ethanol/water buffered at pH 5.0, 7.0, and 10.2 with 0.25 M sodium acetate, 0.1 M potassium phosphate, and 0.1 M sodium carbonate was chemically irreversible and characteristic of an EC … -type reaction mechanism; heterogeneous electron transfer followed by homogeneous chemical reactions. Cathodic peak potentials at pH 5.0 and 7.0 were ?0.760 and ?0.820 V vs SCE. At pH 10.2 two cathodic peaks were observed at ?0.840 and ?1.17 V vs SCE. In protolytic solvent at pH 5.0 cathodic peak current varied linearly as a function of the square root of the scan rate. Thus, the electrode reaction was limited by diffusion. Electron stoichiometry for reduction of nitrofen in protolytic solvent was four. The fate of new redox species generated in protolytic solvent at pH 7.0 was examined upon subsequent multiple scans at 200 mV/s. Initial reduction at ?0.820 V vs SCE was most likely centered at the nitro group, yielding the four-electron hydroxylamine product. Oxidation at 0.020 V vs SCE was thought to correspond to the two-electron oxidation of hydroxylamine to the nitroso derivative.  相似文献   
90.
In Maryland, Lyme disease (LD) is the most widely reported tickborne disease. All laboratories and healthcare providers are required to report LD cases to the local health department. Given the large volume of LD reports, the nuances of diagnosing and reporting LD, and the effort required for investigations by local health department staff, surveillance for LD is burdensome and subject to underreporting. To determine the degree to which misclassification occurs in Maryland, we reviewed medical records for a sample of LD reports from 2009. We characterized what proportion of suspected and “not a case” reports could be reclassified as confirmed or probable once additional information was obtained from medical record review, explored the reasons for misclassification, and determined multipliers for a more accurate number of LD cases. We reviewed medical records for reports originally classified as suspected (n = 44) and “not a case” (n = 92). Of these 136 records, 31 (23%) suspected cases and “not a case” reports were reclassified. We calculated multipliers and applied them to the case counts from 2009, and estimate an additional 269 confirmed and probable cases, a 13.3% increase. Reasons for misclassification fell into three general categories: lack of clinical or diagnostic information from the provider; surveillance process errors; and incomplete information provided on laboratory reports. These multipliers can be used to calculate a better approximation of the true number of LD cases in Maryland, but these multipliers only account for underreporting due to misclassification, and do not account for cases that are not reported at all (e.g., LD diagnoses based on erythema migrans alone that are not reported) or for cases that are not investigated. Knowing that misclassification of cases occurs during the existing LD surveillance process underscores the complexities of LD surveillance, which further reinforces the need to find alternative approaches to LD surveillance.  相似文献   
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