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991.
Determination of the acid-base status in 50 horses admitted with colic between December 1998 and May 1999 下载免费PDF全文
Nappert G Johnson PJ 《The Canadian veterinary journal. La revue veterinaire canadienne》2001,42(9):703-707
The purpose of the present study was to investigate the acid-base status and the concentration of organic acids in horses with colic caused by various disorders. Blood samples were collected from 50 horses with colic and from 20 controls. No intravenous fluids had been given prior to sample collection. Identified causes of colic included gastric ulceration, small intestinal volvulus, cecal intussusception, cecal rupture, colonic impaction, left dorsal colon displacement, right dorsal colon displacement, colonic volvulus, colitis, peritonitis, and uterine torsion. Thirty-seven horses recovered from treatment of colic, 8 horses were euthanized, and 5 died. Most cases were not in severe metabolic acidosis. In previous studies, most horses presented for diagnosis and treatment of colic were in metabolic acidosis and in shock. 相似文献
992.
Kerth CR Carr MA Ramsey CB Brooks JC Johnson RC Cannon JE Miller MF 《Journal of animal science》2001,79(9):2346-2355
We examined the effects of vitamin and mineral supplementation of the finishing diet on growth and accelerated chilling of carcasses on carcass and muscle traits of halothane gene carrier and noncarrier pigs. Barrows and gilts that were either monomutants (MON, n = 49) or noncarriers (NON, n = 28) of the halothane gene were fed a standard finishing diet until they reached 86 kg. They then were randomly assigned to one of four finishing diets formulated to contain 11 IU/kg vitamin E (0), 311 IU/kg vitamin E plus additional vitamins and minerals (300), 611 IU/kg vitamin E plus additional vitamins and minerals (600), or 911 IU/kg vitamin E plus additional vitamins and minerals (900) until they were slaughtered (118 kg). Alternating carcass sides were assigned either a normal chilling procedure (NC, 4 degrees C for 24 h) or an accelerated chilling procedure (AC, -20 degrees C for 1.5 h and then 4 degrees C for 22.5 h). Supplementing vitamin E in the finishing diet increased (P < 0.05) the concentration of vitamin E in the longissimus muscle. Supplementing vitamin E in the diets of MON pigs did not affect color, firmness, or cooking losses of loins or color and firmness of hams. For the NON genotype, increasing the level of vitamin E in the diet decreased (P < 0.05) the percentage of PSE loins and hams. Color and firmness scores of the gluteus medius and longissimus muscles were improved 0.4 unit (P < 0.005) by AC compared with NC of carcasses. Loin chop juiciness and flavor were improved (P < 0.05) in the MON genotype for AC compared to NC. Accelerated chilling reduced (P < 0.05) the percentage of PSE loins from 38 to 17% and PSE hams from 32 to 10% for the MON genotype, but percentage of PSE was not affected (P > 0.05) by chilling treatment for the NON genotype. No interaction between diet and chill treatments existed for muscle quality traits (P > 0.05). Supplementing finishing diets of NON pigs with at least 600 IU/kg vitamin E, in addition to other vitamins and minerals, or accelerated chilling of MON carcasses can reduce the incidence of PSE pork. 相似文献
993.
Stafford Johnson M Martin M Binns S Day MJ 《The Journal of small animal practice》2004,45(11):546-552
A retrospective study of 143 dogs with pericardial effusion is presented, including a statistical analysis of survival time. Cases were classified into those in which a mass was seen on echocardiography (echo-positive) and those in which no mass could be identified (echo-negative). Forty-four dogs were echo-positive and 99 were echo-negative. The median survival time (MST) was 1068 days for echo-negative dogs and 26 days for echo-positive dogs. Dogs with a history of collapse were more likely to present with a mass on echocardiography. Those presenting with collapse had an MST of 30 days compared with 605 days for those without collapse. Echo-negative dogs tended to present with ascites and generally had a larger volume of pericardial effusion. The median survival for dogs presenting with ascites was 605 days compared with 45 days for those without ascites. Among echo-negative dogs, 64 per cent had a relapse of their effusion. Subtotal pericardiectomy was performed in 31 echo-negative dogs. The procedure had a perioperative mortality of 13 per cent but provided a favourable long-term prognosis. Dogs undergoing pericardiectomy had a median survival of 1218 days compared with 532 days for those not undergoing surgery. 相似文献
994.
Survivin: a bifunctional inhibitor of apoptosis protein 总被引:44,自引:0,他引:44
Survivin is a recently discovered protein belonging to the inhibitor of apoptosis (IAP) gene family. IAP molecules are characterized by both the presence of a zinc-binding fold termed the baculoviral IAP repeat and the ability to suppress apoptosis. In addition to inhibiting apoptosis, survivin is essential for proper cell division. Survivin is expressed during embryonal development but is absent in most normal, terminally differentiated tissues. Survivin is also upregulated in a variety of human cancers, and its expression in tumors is associated with a more aggressive phenotype, shorter survival times, and a decreased response to chemotherapy. The exact mechanism behind the ability of survivin to inhibit apoptosis is still unclear. Furthermore, it is not known why this protein is upregulated in cancer. The purpose of this article is to provide an overview of the current knowledge of survivin, including its role in cell division and its expression in normal and neoplastic tissues. Although much of the current research in this field is focused on human medicine, this area also has potential significance for veterinary species. 相似文献
995.
A genome scan for quantitative trait loci and imprinted regions affecting reproduction in pigs 总被引:1,自引:0,他引:1
Quantitative trait loci for reproductive traits in a three-generation resource population of a cross between low-indexing pigs from a control line and high-indexing pigs from a line selected 10 generations for increased index of ovulation rate and embryonic survival are reported. Phenotypic data were collected in F2 females for birth weight (BWT, n = 428), weaning weight (WWT, n = 405), age at puberty (AP, n = 295), ovulation rate (OR, n = 423), number of fully formed pigs (FF, n = 370), number of pigs born alive (NBA, n = 370), number of mummified pigs (MUM, n = 370), and number of stillborn pigs (NSB, n = 370). Grandparent, F1, and F2 animals were genotyped for 151 microsatellite markers. Sixteen putative QTL (P < 0.10) for reproductive traits were identified in previous analyses of these data with single QTL line-cross models. Data were reanalyzed with multiple QTL models, including imprinting effects. Data also were analyzed with half-sib models. Permutation was used to establish genome-wide significance levels ( = 0.01, 0.05, and 0.10). Thirty-one putative QTL for reproductive traits and two QTL for birth weight were identified (P < 0.10). One Mendelian QTL for FF (P < 0.05), one for NBA (P < 0.05), three for NSB (P < 0.05), three for NN (P < 0.05), seven for AP (P < 0.10), five for MUM (P < 0.10), and one for BWT (P < 0.10) were found. Partial imprinting of QTL affecting OR (P < 0.01), BWT (P < 0.05), and MUM (P < 0.05) was detected. There were four paternally expressed QTL for NN (P < 0.10) and one each for AP (P < 0.05) and MUM (P < 0.10). Maternally expressed QTL affecting NSB (P < 0.10), NN (P < 0.10), and MUM (P < 0.10) were detected. No QTL were detected with half-sib analyses. Multiple QTL models with imprinting effects are more appropriate for analyzing F2 data than single Mendelian QTL line-cross models. 相似文献
996.
Johnson SS Coscarelli EM Davis JP Zaya RM Day JS Barsuhn CL Martin RA Vidmar TJ Lee BH Conder GA Geary TG Ho NF Thompson DP 《Journal of veterinary pharmacology and therapeutics》2004,27(3):169-181
The interrelationships between physicochemical properties, absorption and potency of 2-desoxoparaherquamide and five analogs, representing a new anthelmintic class, were evaluated in in vitro and in vivo assays. At pH 7.5, rates of drug absorption by the gastrointestinal nematode Haemonchus contortus and jird small intestine, parameterized by the permeability coefficient, P(e), ranged from 1.2-2.4 x 10(-4) cm/min (nematode) to 2.5-5.5 x 10(-3) cm/min (jird). In the jird intestine, absorption was pH-dependent, with P(e) at pH 7.5 being twice that at pH 4.5, reflecting the negative influence of protonation on transport of these weakly basic molecules. Each compound rapidly paralyzed H. contortus during in vitro exposure to therapeutically relevant concentrations (1-10 microm). The kinetics of drug action on motility in vivo mirrored their in vitro effects; motility concentrations were reduced in nematodes collected from jird stomach 3 h following oral drug dosing, by which time > or =50% clearance of the parasites had occurred. The nematode/medium partition coefficient K ranged from 10.1 to 16.1, consistent with the lipophilic nature of the compounds. The time required to reduce motility in vitro by 50% (t50*) and P(e) were used to determine C(n)*, the concentration of drug in the nematode at t50*, as an indicator of intrinsic potency. In the jird, the apparent potencies of the compounds were insensitive to route of administration (i.e. oral = i.v. = i.p. = i.m.) for H. contortus and two other gastrointestinal nematodes, Ostertagia ostertagi and Trichostrongylus colubriformis; topical administration, however, required three to 10-fold higher doses for equivalent efficacy. 相似文献
997.
998.
We reviewed Bayesian approaches for animal-level and herd-level prevalence estimation based on cross-sectional sampling designs and demonstrated fitting of these models using the WinBUGS software. We considered estimation of infection prevalence based on use of a single diagnostic test applied to a single herd with binomial and hypergeometric sampling. We then considered multiple herds under binomial sampling with the primary goal of estimating the prevalence distribution and the proportion of infected herds. A new model is presented that can be used to estimate the herd-level prevalence in a region, including the posterior probability that all herds are non-infected. Using this model, inferences for the distribution of prevalences, mean prevalence in the region, and predicted prevalence of herds in the region (including the predicted probability of zero prevalence) are also available. In the models presented, both animal- and herd-level prevalences are modeled as mixture distributions to allow for zero infection prevalences. (If mixture models for the prevalences were not used, prevalence estimates might be artificially inflated, especially in herds and regions with low or zero prevalence.) Finally, we considered estimation of animal-level prevalence based on pooled samples. 相似文献
999.
1000.
Keegan KG Arafat S Skubic M Wilson DA Kramer J Messer NM Johnson PJ O'Brien DP Johnson G 《Equine veterinary journal》2004,36(8):712-717
REASONS FOR PERFORMING STUDY: Subjective neurological evaluation in horses is prone to bias. An objective method of spinal ataxia detection is not subject to these limitations and could be of use in equine practice and research. HYPOTHESIS: Kinematic data in the walking horse can differentiate normal and spinal ataxic horses. METHODS: Twelve normal and 12 spinal ataxic horses were evaluated by kinematic analysis walking on a treadmill. Each body position signal was reduced to a scalar measure of uncertainty then fuzzy clustered into normal or ataxic groups. Correct classification percentage (CCP) was then calculated using membership values of each horse in the 2 groups. Subsequently, a guided search for measure combinations with high CCP was performed. RESULTS: Eight measures of body position resulted in CCP > or = 70%. Several combinations of 4-5 measures resulted in 100% CCP. All combinations with 100% CCP could be obtained with one body marker on the back measuring vertical and horizontal movement and one body marker each on the right fore- and hindlimb measuring vertical movement. CONCLUSIONS AND POTENTIAL RELEVANCE: Kinematic gait analysis using simple body marker combinations can be used objectively to detect spinal ataxia in horses. 相似文献