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591.
The role of nutrition in canine hip dysplasia is a multifactorial as the disease itself. Large and giant breeds primarily are at risk for the disease. Rate of growth, feeding methods, feed consumption, specific nutrients, and electrolyte balances within the diet have all been shown to influence hip dysplasia. Known nutritional risk factors are rapid weight gain and excessive calcium supplementation. Nutritional factors with less secure roles in their influence on the disease process are vitamin C, protein, and carbohydrates. There exists a need to identify further and control the various nutritional factors in the diet that influence canine hip dysplasia.  相似文献   
592.
Selection intensity and generation interval were evaluated in a Hereford cattle herd made up of 14 inbred lines and 14 linecross groups corresponding to the lines of inbred sires at the Suan Juan Basin Research Center, Hesperus, Colorado. Selection indexes practiced were calculated in retrospect. Analyses of the records collected from 1946 through 1973 involved weaning weight (WW) and postweaning traits in males and females. Analyses by line were performed for the inbreds, while pooled analyses were done on the inbred and linecross populations. From records of 1,239 calves weaned, age of sire averaged 3.75 yr compared with 4.52 yr for age of dam, showing faster generation turnover for sires than for dams. Generation interval determined as actual age of midparent was 4.13 yr. Selection applied for WW, evaluated as annual selection differentials within inbred lines and then pooled over all lines, averaged .55 standard deviations (sigma)/generation for sires. For females, selection was much less intense. Midparent selection differential amounted to .33 sigma/generation. For sires, pooled standardized selection differentials per generation over all lines during the postweaning gain period were .49 sigma, .46 sigma, .40 sigma, -.20 sigma, -.10 sigma and .69 sigma, respectively, for initial weight, final weight, feed consumed, feed efficiency (FE, unadjusted and adjusted) and average daily gain (ADG). Selection of females for postweaning traits was not intense. Selection index actually practiced in retrospect for sires was: IS = .4461 (WW) - .0092 (FE) + .6126 (ADG). The indexes for dams included WW, 12-mo weight (12W), 18-mo weight (18W), mature spring weight (SPW) and mature fall weight (FAW) and were: for inbred dams, ID = .1824 (WW) - .0284 (12W) + .0736 (18W) - .1097 (SPW) - .1097 (FAW); for linecross dams, ID = .2693 (WW) - .2960 (12W) + .0147 (18W) + .1185 (SPW) - .0354 (FAW). The corresponding index selection differentials were .818, .203 and .209. Sire index selection differentials represent about 79% of the total selection differentials.  相似文献   
593.
Ninety-two purebred Jersey fetuses from clinically normal dams derived from a variety of sources but unexposed to experimental infection, were killed between 80 and 260 days after conception and dissected to provide basic parameters of a normal population. Organs and tissues were weighed and measured and the equations for the regression of the values on fetal age evaluated. Growth followed a sigmoid curve with rapid changes in growth rate between 140 and 170 days' gestation. While a few variables increased their growth rate over the late fetal period, the majority maintained a low even rate of growth. Thyroid and cerebellum weights showed a marked reduction in growth rate at this time. Long bone length and crown-anus length were the most predictable parameters for a given gestational age.  相似文献   
594.
595.
Refrigerated shipping trials from Australia to the United Kingdom were organised to test methods of unitising cell pack cartons based on the use of palletizing adhesives and horizontal strapping. The basic system was effective with only one horizontal strap required. The trials indicated that a palletizing adhesive with low tack strength was required to give less flap damage when de-unitising.  相似文献   
596.
Cisplatin Toxicity in Cats   总被引:2,自引:1,他引:1  
Cisplatin (cis-diamminedichloroplatinum; Platinol, Bristol, Syracuse, NY) was administered to 11 cats, divided into three groups of experimental and clinical patients. In group 1, cisplatin was administered at a dose of 60 mg/m2 to four cats. In an attempt to avoid renal toxicity, saline diuresis was induced by administering 0.9% saline solution intravenously at a rate of 20 ml/kg/hr for 4 hours before and 2 hours after cisplatin administration. All four cats became dyspneic and died 48-96 hours after cisplatin administration. Postmortem findings included severe hydrothorax, pulmonary edema, and mediastinal edema. In group 2, four experimental cats entered a trial comparing the effects of saline diuresis and cisplatin (60 mg/m2) with the effects of saline diuresis and placebo (0.9% saline solution). The cats in the saline control group remained completely normal, while the cats that received cisplatin developed clinical signs and gross postmortem pulmonary changes identical to those in the first group of cats. Histopathologic examination showed that the alveolar septa were thickened and congested, and contained macrophages, occasional neutrophils, thrombi, and small foci of necrosis and fibrin. Microangiopathic changes were seen in the alveolar capillaries. In the third group, three additional cats were treated with a lower dose of cisplatin. Two cats that received 40 mg/m2 of cisplatin developed pulmonary changes similar to, but less severe than, those seen in the cats that received the higher dose of cisplatin. One cat treated with 20 mg/m2 of cisplatin showed no pulmonary changes ante mortem or post mortem. This series of 11 clinical and experimental cases identifies an apparent species-specific, dose-related, primary pulmonary toxicity of cisplatin in cats.  相似文献   
597.
In a retrospective study, we examined the case records for 69 horses with noncomminuted fractures of the proximal phalanx, excluding proximal chip fractures. Forty-nine of the horses sustained the fracture while racing or training for racing. Radiographic examination of all affected limbs was performed, and fractures were classified into 6 noncomminuted types: midsagittal fractures, including short incomplete midsagittal fractures, long incomplete midsagittal (LIMS) fractures, and complete midsagittal (CMS) fractures; dorsal frontal fractures; distal joint fractures; plantar process fractures; physeal fractures; and oblique fractures. Four horses were destroyed before treatment. Sixty-five horses were treated and 63 survived to go home. Long-term follow-up evaluation of the horses that were sent home revealed that 4 were euthanatized after discharge because of persistent lameness of the fractured limb. Of the 59 remaining horses, 34 returned to racing, 7 were used as show or pleasure riding animals, 8 were used for breeding, and 10 were lost to follow-up. More Standardbreds with noncomminuted proximal phalangeal fractures returned to racing than did Thoroughbreds. Of 30 Standardbreds that raced or trained before the fracture, 23 (76.7%) returned to racing--8 to their previous level of performance, 11 to a lower level of performance, and 4 to an unknown level of performance. The Standardbreds that returned to racing were horses with physeal fractures (2/2), LIMS fractures (4/4), CMS fractures (11/16), short incomplete midsagittal fractures (4/7), distal joint fractures (1/2), and plantar process fractures (1/2). Of 21 Thoroughbreds that raced or trained before the injury, 11 (52.4%) returned to racing--7 to their previous level of performance and 4 to a lower level of performance.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
598.
599.
Records of 104 crossbred and 33 straightbred individually fed cow-calf units were used to study the effects of heterosis on total cow-calf feed efficiency in the production of weight of calf at weaning, 168 d postweaning, slaughter and in the carcass. The cows were Angus, Hereford, Charolais and reciprocal crosses of these breeds. The calves were straightbred and all possible two-breed backcrosses and three-breed crosses produced from first cross cows. The efficiency of the cow-calf unit was defined as kg of calf produced per kg of total TDN (total digestible nutrients) consumed by the cow-calf pair. Total feed consumed by the cows was for an average period of 315 d, from approximately November 21 to October 2. Total calf TDN consisted of creep to weaning and feed during the postweaning fattening period to slaughter. For all measures of cow-calf unit efficiency studied, the heterosis estimates were small but generally positive, ranging from -.8 to 2.1%. The average advantage of all crosses over the straightbred parents for the conversion of total feed consumed by cow-calf pair to calf weight at weaning was 2%. Heterosis effects, individual and maternal combined, on the average, among two-breed backcrosses and the three-breed crosses were essentially the same. Among the three groups of first-cross cows compared, the study indicated that a slight advantage in total cow-calf efficiency was exhibited by the Angus X Hereford cross.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
600.
Serum concentrations of lipid-soluble (glycolipid) sialic acid were determined for 96 client-owned dogs, of which 24 were diagnosed as bearing tumors. A markedly increased concentration of lipid-soluble serum sialic acid was found in 22 of 24 tumor-bearing dogs (92%) compared with 17 of 72 dogs with other definitely false-positive, based on necropsy and follow-up work. Almost all others had acute infections or terminal congestive disorders and were potential tumor bearers. The values obtained appeared to be independent of the sex or age (or both) of the dogs. Based on the analysis of a single biochemical variable, the procedure may permit cancer detection applicable to a wide range of tumor types in dogs if evaluated in terms of the general health status of the animal.  相似文献   
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