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241.
Objective – To determine: (1) changes in blood ammonia, bile acid (BA), bilirubin, triglyceride, and glucose concentrations and liver enzyme activities in perioperative colic patients and (2) the association between these laboratory findings and short‐term survival. Design – Prospective observational clinical study. Animals – Thirty‐two adult horses undergoing exploratory celiotomy for colic. Interventions – None. Measurements and Main Results – Blood samples were collected preoperatively and at 24–36 and 72–84 hours postoperatively and analyzed for blood ammonia, BA, bilirubin, triglyceride, and glucose concentrations and sorbitol dehydrogenase (SDH) and gamma glutamyl transferase (GGT) activities. Short‐term survival was defined as survival to hospital discharge. Data were analyzed using a Fisher's exact test and analysis of variance. Mildly increased blood ammonia concentrations were present in 2 horses at admission. Postoperative blood ammonia concentrations were within reference intervals in all horses. There were increases in liver enzyme activities as well as in BA, triglyceride, and total bilirubin concentrations. Horses with markedly increased admission BA concentrations and SDH activities did not survive. BA concentrations and SDH activities decreased postoperatively. There was no association between GGT activity and survival; GGT activity remained increased postoperatively. Blood triglyceride concentration was increased in almost all horses postoperatively; horses that did not survive had higher triglyceride concentrations at 24–36 hours postoperatively than horses that survived. Conclusion – Alterations in metabolism and hepatobiliary function are common in colic patients. The results of this study provide further prognostic indices for colic patients and highlight areas for improvement in patient management.  相似文献   
242.
Abstract: A 3‐year‐old, castrated male, soft‐coated Wheaten Terrier was presented for evaluation of mild lameness, fecal incontinence, lumbosacral pain, and lack of anal tone. Magnetic resonance imaging scan showed a large (8 × 6 × 5 cm) mass invading and expanding the pelvic bones, sacrum, and associated structures. A fine‐needle aspirate of the mass contained many neoplastic cells with high nuclear to cytoplasmic ratios and rare spindle and inflammatory cells. The neoplastic cells were 12–16 μm in diameter, round to cuboidal, basaloid in appearance, and arranged both individually and in loosely cohesive clusters with variably distinct cell borders. Given the location, signalment, and cytologic findings, differential interpretations included a primitive embryonal tumor (eg, neuroblastoma or nephroblastoma in an atypical location) or poorly differentiated carcinoma. The owner elected euthanasia due to the poor prognosis. Abnormal gross findings on necropsy included the pelvic mass and multiple firm, pale, pink‐tan nodules in the lung, which proved to be metastases. On histologic examination, the mass and nodules were composed of irregular islands, lobules, and nests of basaloid cells, which transitioned abruptly into large lakes of “ghost” cells with areas of ossification and calcification, consistent with a diagnosis of malignant pilomatricoma. This unusual presentation of a pilomatricoma adds to our knowledge of expected cytologic findings for this tumor.  相似文献   
243.
  • ? Genetic variation in freezing resistance was evaluated among and within six populations of Spanish wild chestnut (Castanea sativa Miller). The extent to which frost susceptibility was related to phenology and the relationship between population differentiation and climatic conditions was studied.
  • ? Twigs were collected in March and November from saplings (5-year-old trees) of 41 open-pollinated families from the six populations in a provenance-progeny test, and were subjected to artificial freezing. Damage to each twig was assessed as visible browning of bud and of stem tissues.
  • ? Population differences as regards frost damage traits were highly significant (p < 0.01) in both spring and autumn. Family differences within populations were low, often non-significant, and in all cases smaller than differences among populations. Population means were closely correlated with the parental drought and frost conditions. Populations originating from dry areas or from regions where frost seldom occurs were the least resistant.
  • ? Drought is suggested to be the one of the most important selective agents that shapes population differentiation in Spanish wild chestnut, while frost may be more important in northern Spain. Phenological differences are not always good predictors of the degree of frost damage. Thus, freezing tests should be used to detect frost susceptibility in chestnuts.
  •   相似文献   
    244.
    Enteromyxum leei is a myxozoan histozoic parasite that infects the intestine of several teleost fish species. In gilthead sea bream (Sparus aurata), it provokes a chronic disease, entailing anorexia, delayed growth, reduced marketability and mortality. Direct fish-to-fish transmission, relevant in aquaculture conditions, has been demonstrated for E. leei via effluent, cohabitation, and oral and anal routes. However, the minimum time of exposure for infection has not been established, nor the possible effect on the fish immune response. Two effluent trials were performed at different temperatures (high: average of 25.6°C; and low: constant at 18°C), different times of exposure to the effluent (1, 3, 5 and 7 weeks) and different population densities. The results showed that 1 week was enough to infect 100% of fish at high temperature and 58.3% at low temperature. High temperature not only increased the prevalence of infection in posterior intestine, but also induced a higher production of specific antibodies, limiting the progression of the infection along the intestine. Longer time of exposure to the parasite and higher fish densities facilitated E. leei infection. These results show that effective diagnosis, lowering animal density and removal of infected fish are key aspects to manage this disease in aquaculture facilities.  相似文献   
    245.
    The experiment was conducted with the aim of determining the attractability and palatability of liquid protein hydrolysates for Nile tilapia. Five experimental diets were formulated containing 5% inclusion of fishmeal (FPE; positive control), 5% inclusion of liquid protein hydrolysate of porcine mucosa (PHM), 5% inclusion of liquid protein hydrolysate of poultry (PHF), 5% inclusion of liquid fish oil (OPE) and a diet without fishmeal (negative control). Five juveniles (2.51 ± 0.13 g) were distributed in 10 L tanks, and the animals were fed five times a day, with a previous draw being made of the offered diets. The same amount of pellets was offered and the following feeding behaviours were evaluated with the aid of three‐minute footages per feeding: time to capture first pellet, number of rejections, number of approaches without capturing the pellet and number of consumed pellets. None of the observed parameters displayed significant differences (p > .05), and all diets presented negative palatability indexes in comparison to FPE. The SPE diet provided a attractability and palatability index of 6.17%, while OPE index was 2.87%, PHM 2.82% and PHF 2.74%. Both PHF and PHM reduced the final consumption of pellets in comparison to FPE in approximately 28% and 20%, respectively, although it did not present significant values.  相似文献   
    246.
    BackgroundSuid gammaherpesvirus 3, 4, and 5 (porcine lymphotropic herpesvirus – PLHV-1, -2, and -3) are viruses that infect domestic and feral pigs.ObjectivesThis study examined the presence of PLHV DNA in biological samples from free-living wild boars circulating in a Brazilian geographical region with a high density of commercial domestic pigs.MethodsLung samples of 50 free-living wild boars were collected by exotic wildlife controller agents between 2017 and 2019 in the state of Paraná, southern Brazil. Lung and spleen fragments were obtained from six fetuses collected by hysterectomy post mortem from a pregnant sow. A polymerase chain reaction (PCR) assay using consensus primers (pan-herpesviruses) was performed to detect PLHV DNA. The samples showing positive results for PLHV DNA were submitted to single-round PCR assays with the specific primers for identifying PLHV-1 (213-S/215-As), PLHV-2 (208-S/212-As), and PLHV-3 (886s/886As). The specificity of the species-specific PCR products was assessed by nucleotide sequencing of the amplicons.ResultsForty-eight (96%) of the 50 lung samples analyzed were positive for PLHV by PCR using pan-herpesvirus primers. In 33 (68.75%) of the positive samples, at least two PLHV species were identified simultaneously. The DNA of PLHV-1, -2, and -3 was found in free-living wild boars of all ages, but not in the fetuses, even though they were from a sow that tested positive for all three viruses.ConclusionThese viruses are endemic to the population of feral pigs in the Brazilian region evaluated, as well as in domesticated pigs.  相似文献   
    247.
    248.
    Flavor and taste are sensorial attributes of virgin olive oil (VOO) highly appreciated by consumers. Among the organoleptic properties of VOO, bitterness is related to the natural phenolic compounds present in the oil. Sensorial analysis is the official method to evaluate VOO flavor and bitterness, which requires highly specialized experts. Alternatively, methods based on physicochemical determinations could be useful for the industry. The present work presents a flow-injection analysis system for the direct automatic determination of bitterness and total phenolic compounds in VOO without prior isolation, based on the spectral shift undergone by phenolic compounds upon pH variation. This system enables a complete automation of the process, including dilution of the sample and its sequential injection into buffer solutions of acidic and alkaline pH. The variation of the absorbance at 274 nm showed a high correlation with bitterness and the total phenolic content of VOO, due to the close relationship between these two parameters. Thus, the proposed method determines the bitterness and phenolic compounds, with results similar to those from reference methods (relative errors ranging from 1% to 8% for bitterness and from 2% and 7% for phenolic compounds). The precision evaluated at two levels of both parameters ranged between 0.6% and 1.5% for bitterness and between 0.7% and 2.6% for phenolic compounds.  相似文献   
    249.
    The effect of graded levels of dietary available phosphorus (AP) on large Nile tilapia (145.87 ± 9.51 g) performance, feed efficiency, body composition and mineral retention in vertebrae was evaluated. All male fish were distributed into three replicates in fiberglass aquaria (800 L each; 12 fish per tank) for 87 days and hand fed to pelletized diets three times a day until apparent satiation. Diets with approximately 302 g kg?1 of digestible protein and 15.2 kJ g?1 of digestible energy with graded levels of dibasic phosphate yield AP levels of 2.39, 4.17, 6.12 and 8.91 g kg?1. At the end of the trial, feed intake, hepatosomatic index, fillet yield, whole body moisture and crude protein of fish fed 2.39–8.91 g kg?1 of AP diets were not significantly different. The supplementation of 6.12 and 8.91 g kg?1 of AP resulted in significantly increased weight gain, whole body ash and calcium. Whole body crude lipids significantly decreased with increasing AP from 6.12 to 8.91 g kg?1. However, concentration of zinc in the vertebrae was not affected by dietary treatments. The magnesium contents of the fish vertebrae were lower in fish fed lower dietary AP level. No effects of the dietary AP on apparent digestibility coefficients of energy and nutrients were observed. The study indicated that the dietary AP level of at least 6.12 g kg?1 satisfies the needs for growth performance, body composition and bone mineralization of large Nile tilapia.  相似文献   
    250.
    A 28-day indoor trial was conducted to evaluate the water quality, phytoplankton composition and growth of Litopenaeus vannamei in an integrated biofloc system with Gracilaria birdiae and Gracilaria domingensis. The experimental design was completely randomized with three treatments: control (shrimp monoculture); SB (shrimp and G. birdiae) and SD (shrimp and G. domingensis), all with three replicates. Random sampling was done (6 % of total population per experimental unit) to confirm white spot syndrome Virus (WSSV) infection using nested-PCR analysis due to suspicion of presence of the virus in the experiment (treatment and control groups). Shrimp L. vannamei (2.63 ± 0.10 g) were stocked in experimental tanks at a density of 425 shrimp m?3, and the Gracilaria was stocked at a biomass of 2.0 kg m?3. Shrimp mortality began in both the experimental and control groups at 10 days of culture. The integrated biofloc system (shrimp and seaweed) increased settleable solids (by 26–52 %); final weight (by 6–21 %); weekly growth (by 17–43 %); weight gain (by 17–43 %); specific growth rate (by 16–36 %); and yield (by 5–7 %) and decreased feed conversion ratio (by 21–28 %) and Cyanobacteria density about 16 % as compared to the control (shrimp monoculture). The use of red seaweed Gracilaria in an integrated biofloc system can enhance shrimp growth and reduce Cyanobacteria density in the presence of WSSV.  相似文献   
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