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81.
Trypanosoma evansi is the most widely spread of the pathogenic African trypanosomes of animals. The disease (surra) was first diagnosed in the Canary Islands in a dromedary camel in 1997; thus, a control plan was implemented achieving the eventual eradication of T. evansi from most of the infected areas in the Archipelago. However, a little area remains still infected despite the use of the same control measures. To evaluate possible reservoirs in the area a representative sample of domestic ruminants was examined by serological, parasitological and molecular tests. Of a total of 1228 ruminants assessed, 61 (5%) were serologically positive (7 cattle, 21 goats, 33 sheep), but T. evansi could be demonstrated in none of them. According to FreeCalc assessment, cattle and goat populations would be free from disease; however, the results from sheep are not adequate to conclude that the population would be free from disease. As a conclusion, surveillance must be exercised on ruminant farms in the surroundings of the infected area in order to evaluate the possible extension of the disease and their potential role as reservoirs of T. evansi.  相似文献   
82.
83.
Idiopathic hypertrophic pachymeningitis has been described in humans as a rare, chronic progressive non-specific inflammatory and fibrotic disease of the dura mater. This is a case series of six canine cases of presumptive or confirmed intracranial idiopathic hypertrophic pachymeningitis. These dogs were included in this retrospective study, based on magnetic resonance imaging findings. All presented with pachymeningeal thickening and enhancement without involvement of the leptomeninges on magnetic resonance imaging and no underlying cause identified on cerebrospinal fluid analysis, complete blood count, serum biochemistry and infectious disease titres. Histopathological examination was available in one case. Response to immunomodulatory treatment (corticosteroids and cytosine arabinoside) was achieved in five cases. Idiopathic hypertrophic pachymeningitis should be considered as a possible differential diagnosis for dogs with pachymeningeal thickening on magnetic resonance imaging and no identified underlying cause. The prognosis appears to be fair to poor.  相似文献   
84.
A total of 229 Spanish Actinobacillus pleuropneumoniae isolates recovered from diseased pigs with pleuropneumonia from 1997 to 2004 was tested for their susceptibility to 11 antimicrobials in a broth microdilution method. All the isolates were susceptible to florfenicol and most of them to cephalothin; however, a high rate of resistance was observed to tetracycline. A bimodal or multimodal distribution of isolates over the MIC range were observed for penicillins, tetracycline, trimethoprim, sulfisoxazole and nalidixic acid, suggesting the development of acquired resistance. Eight resistance patterns were established, and 21.1% of the isolates were resistant to at least two antimicrobials. In addition, a considerable increase in the resistance to tetracyclines was observed during the last decade in Spain, when compared with other A. pleuropneumoniae strains isolated during 1987-1988 (Gutiérrez, C.B., Píriz, S., Vadillo, S., Rodríguez Ferri, E.F., 1993. In vitro susceptibility of Actinobacillus pleuropneumoniae strains to 42 antimicrobial agents. Am. J. Vet. Res. 54, 546-550); this finding was also observed for gentamicin in minor percentage.  相似文献   
85.
1. Forty eight diets were tested to develop equations for predicting the apparent metabolisable energy values corrected to zero nitrogen retention (AMEn), of practical poultry feedingstuffs.

2. The effectiveness of different fibre indicators (crude fibre, acid detergent fibre, lignin, neutral detergent fibre and cell wall content) as predictors of AMEn values was assessed. The most efficient measure proved to be cell wall content obtained by an enzymatic procedure (pronase and α‐amylase).

3. The best combinations of variables were, in decreasing order: (1) gross energy (GE), crude protein (CP) and cell wall (CW); (2) ether extract (EE), ash and CW; (3) EE, CP, starch and sugars.

4. When GE, CP and CW variables were used, a significant constant appeared in the linear equation. Another equation without a constant was calculated, using an exponent (1·5) for the CW variable. The residual standard deviation (0·20 MJ/kg) of this equation was about the same as that of the equation with the constant.

  相似文献   
86.

Objective

To compare the effect of propofol and alfaxalone on laryngeal motion under a light plane of anaesthesia in nonbrachycephalic and brachycephalic dogs anaesthetized for nonemergency procedures.

Study design

Prospective, randomized clinical trial.

Animals

A total of 48 client-owned dogs (24 nonbrachycephalic and 24 brachycephalic).

Methods

A standardized premedication of methadone (0.2 mg kg?1) and acepromazine (0.01 mg kg?1) was administered intramuscularly. Dogs were randomly assigned to be induced with increments of propofol (1–4 mg kg?1) or alfaxalone (0.5–2 mg kg?1). Laryngeal assessment was performed under a light plane of anaesthesia by a surgeon (GTH) who was unaware of the induction protocol. Laryngeal movement was assessed as either being present when abduction of the laryngeal cartilages upon inspiration was identified, or absent when abduction was not recognized. Simultaneously, a 60-second video was recorded. The same surgeon (GTH) and an additional surgeon (NK) re-evaluated the videos 1 month later. Categorical comparisons were studied using Chi square and Fisher’s exact test where appropriate. Pairwise evaluation of agreement between scorers was undertaken with the kappa statistic (κ).

Results

There were no significant differences (p > 0.05) identified between the presence or absence of laryngeal motion between dogs administered propofol or alfaxalone, as well as when analysing nonbrachycephalic and brachycephalic dogs separately. The majority of dogs (>75%) maintained some degree of laryngeal motion with both protocols. Agreement between assessors was excellent (κ = 0.822).

Conclusions

Alfaxalone maintained laryngeal motion similarly to propofol in nonbrachycephalic and brachycephalic dogs.

Clinical relevance

Both agents would appear appropriate for allowing assessment of laryngeal motion in nonbrachycephalic and brachycephalic dogs. The assessment technique of subjective evaluation of laryngeal motion via peroral laryngoscopy under a light plane of anaesthesia produced consistent results amongst assessors, regardless of the induction agent used.  相似文献   
87.
An in-office allergy screening kit was evaluated in 10 dogs that had no clinical signs of atopy but had various intestinal parasites. All 10 dogs had a positive reaction to the dust mite Dermatophagoïdes farinae, and four dogs had positive reactions to at least one other group of allergens. The kit as presently marketed gives numerous false positive results in parasitized nonatopic dogs.  相似文献   
88.
The authors of this paper have produced live vaccine to cope with infectious agalactia in goat. The vaccine (culture) was used on 360, 924 goats kept on ajmaks in Bajanchongor and Gobi-Altaj, in 1986. The number of pathologically affected goats went down by a factor of 4.5, as compared to 1985. Mortality was reduced to one third. Abortions declined by a factor of 2.6 and infertility among goats by 1.6. The conclusion is that sheep of the Mongolian breed are not susceptible to infectious agalactia. Large-scale production tests of live cultures supported hopes for successful action on this infectious disease under Mongolian conditions.  相似文献   
89.
Spontaneous and experimental poisoning with the swainsonine-containing and calystegine-containing plant Ipomoea carnea subsp fistulosa is described. Three of 8 goats presenting with emaciation, weakness, symmetrical ataxia, posterior paresis, proprioceptive deficits, abnormal posture, abnormal postural reaction, and muscle hypertonia were necropsied. I fistulosa was suspected to be the cause of the neurologic disease in all cases. An experiment was conducted to confirm the diagnosis using 12 goats and diets containing 3 different concentrations of the plant. All goats fed I fistulosa developed neurological signs that were similar to those observed in the spontaneous intoxication. Muscle atrophy and pallor were the only macroscopic changes observed in spontaneous and in experimental intoxication. Histological lesions of spontaneous and experimental animals were similar. The most prominent lesion was cytoplasmic vacuolation in neurons of the central and the autonomous nervous system, pancreatic acinar cells, hepatocytes, Kupffer cells, follicular epithelial cells of the thyroid gland, and macrophages of the lymphatic tissues. Neuronal necrosis, axonal spheroids formation, and astrogliosis were additionally observed in the brain. Ultrastructurally, the cytoplasmic vacuoles consisted of distended lysosomes surrounded by a single-layered membrane. Nonreduced end-rests or sequence of alpha-Man, alpha-Glc, beta(1-4)-GlcNAc, and NeuNAc on lysosomal membrane were revealed by lectin histochemistry. Samples of plants used in the experimental trial contained swainsonine and calystegine and their intermediary derivate. We conclude that I fistulosa induces a glycoprotein storage disease primarily based on the inhibition of the lysosomal alpha-mannosidase by the alkaloid swainsonine.  相似文献   
90.
OBJECTIVE: To compare the structural properties of interlocking nails (ILNs) locked with bolts (ILNb) to ILN locked with extended bolts connected with a type-IA external skeletal fixator (ILN-ESF) in a fracture gap model. STUDY DESIGN: Experimental study. SAMPLE POPULATION: Synthetic tibial bone substitutes. METHODS: Custom-made synthetic tibial bone substitutes were implanted with standard ILNs locked with either bolts or extended bolts connected to an external skeletal fixation (ESF). Constructs were tested in torsion, bending, and axial compression (n=4/testing mode). Data, consisting of construct compliance and associated deformation, were compared using t-tests. RESULTS: The ILN-ESF construct compliance and deformation were significantly less than those of the ILNb construct in torsion, bending, and compression (P<.001). Slack was present in the ILNb construct under torsion and bending, but not in the ILN-ESF construct, regardless of testing mode. CONCLUSIONS: Substitution of locking bolts with extended bolts connected to an ESF significantly reduced the construct compliance and overall deformation in torsion, bending, and compression. Furthermore, the inherent slack of the ILNb was eliminated by the use of an ESF in torsion and bending. CLINICAL RELEVANCE: The improvement in structural properties of the ILN-ESF constructs could diminish interfragmentary motion at the fracture site and potentially improve bone healing.  相似文献   
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