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101.
The aim of the following investigation was to study the effect of beta-carotin serum concentrations on reproductive performance in dairy cows. Blood samples were collected from 201 cows 3 to 4 weeks antepartum, 1 to 2 weeks postpartum and at the time of insemination. Concentrations of beta-carotin in blood serum were determined via HPLC. The incidence of retained placental fetal membranes, endometritis, ovarian cysts as well as the beginning of the oestrous cycle and various measures of fertility such as first service conception rate, pregnancy index, interval from calving to first insemination, interval from calving to conception, interval from first insemination to conception and expected calving interval were recorded and analysed. The beta-carotin serum concentrations were not related to the incidence of retained placental fetal membranes, endometritis, ovarian cysts or the onset of cyclicity post partum. Cows with lower beta-carotin concentrations partially seemed to have a reduced reproductive performance than cows with higher beta-carotin concentrations. Overall, our results suggest only a minor relationship between the beta-carotin serum concentration and fertility in dairy cows.  相似文献   
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A cross-sectional study involving 147 pig farms across England was conducted in 2008-2009. Farm severity of post-weaning multi-systemic wasting syndrome (PMWS) was estimated through the use of an algorithm that combined data on post-weaning mortality, PMWS morbidity and proportion of porcine circovirus type 2 PCR positive pigs. Farms were classified as non/slightly, moderately or highly affected by PMWS. Data on potential PMWS risk factors were collected through interviews, on-farm assessment and serological sampling. Risk factors were identified using multivariable ordinal logistic regression and multivariable linear regression. Factors associated with increased PMWS severity were rearing growers indoors (OR=23.7), requiring a higher number of veterinarian visits per year (OR=9.6), having poorly isolated hospital pens (OR=6.4), buying replacement boars (OR=4.8) and seropositivity to Mycoplasma hyopneumoniae (OR=4.29); factors associated with decreased PMWS severity were low stocking density for growers (OR=0.07), adjusting diets at least three times between weaning and 14 weeks of age (OR=0.12), and requiring visitors to be at least 2 days pig free (OR=0.14). This study provides evidence of the association between environmental and management factors and PMWS severity, and suggests that other pathogens may be important co-factors for the disease. In addition, this study highlights the potential efficacy of biosecurity measures in the reduction/prevention of within-farm PMWS severity.  相似文献   
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The objective of the study at hand was to investigate within the framework of a pilot project the preference of weaner pigs for either an ad libitum standard feed with thyme or oregano herb as flavouring additive or an ad libitum standard feed without any herbal additive. Thyme or oregano herbs or a combination of both were offered in two different concentrations each (1% and 0.1%) as additive (experimental diets) in standard diet in comparison to the latter without herbal additive (control diet) free of choice. The dosage of the two herbs in terms of total essential oil(s) in the feeds used in the study was 0.02% or 0.002% (v/w), which was equivalent to 1% or 0.1% herbs in the mixture, respectively. A Latin square according to Williams (1949) was used with 6 groups in order to record possible differences in feed intake. All experimental diets aside from that mixed with 0.1% thyme herb were, in comparison to the control diet, significantly less ingested. Where the weanling was given the choice, it did not choose feed with any flavouring additive. Further studies aimed at assessing the use of herbs as aroma additive in the form of a choice experiment are recommended.  相似文献   
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109.

Objective

To evaluate three routinely used tidal volumes (VT; 10, 12 and 15 mL kg?1) for controlled mechanical ventilation (CMV) in lung-healthy anaesthetized dogs by assessing alveolar ventilation (VTalv) and dead space (DS).

Study design

Prospective, randomized clinical trial.

Animals

A total of 36 client-owned dogs.

Methods

Dogs were randomly allocated to a VT of 10 (G10), 12 (G12) or 15 (G15) mL kg?1. After induction CMV was started. End-tidal carbon dioxide tension was maintained at 4.7–5.3 kPa by changing the respiratory frequency (fR; 6 < fR < 30 breaths minute?1). After 29 minutes, cardiovascular and respiratory variables were recorded for 3 minutes using a multiparameter monitor, volumetric capnography (VCap) and a blood gas analyser. The ratios of VTalv to body weight (VTalv kg?1) and airway DS to VT (VDaw/VT), Bohr's DS (VDBohr), Enghoff's DS (VDBE) and the volume of expired carbon dioxide per breath (VTCO2,br) were calculated. Mean airway pressure (MawP), fR and peak inspiratory pressure (PIP) were recorded. Data were analysed using one-way anova and Student–Newman–Keuls tests with a statistical significance set at p < 0.05.

Results

No differences were observed for demographic data and cardiovascular variables between groups. A total of three dogs were excluded because of technical difficulties and one because of fR > 30. VTalv kg?1 (p = 0.001) increased and VDBohr (p = 0.002) decreased with greater VT. VTCO2,br (p = 0.017) increased and VDaw/VT (p = 0.006), VDBE (p = 0.008) and fR (p = 0.002) decreased between G10 and G15. PIP (p = 0.013) was significantly higher in G15 compared with that in G10 and G12. No changes were observed in MawP.

Conclusions and clinical relevance

A VT of 15 mL kg?1 is most appropriate for CMV in lung-healthy dogs (as evaluated by respiratory mechanics and VCap) and does not impair cardiovascular variables.  相似文献   
110.

Objective

The aim of this study was to validate the Italian version of the UNESP–Botucatu Unidimensional Composite Pain Scale (UCPS-IV) for assessing postoperative pain in cattle.

Study design

Video analysis and psychometric testing.

Animals

A total of 40 Nellore cattle, age 2–3 years, weighing 365 ± 51 kg.

Methods

An English version of the scale was translated to Italian and back translated to English to ensure semantic equivalence. A total of four Italian observers and the researcher who developed the original scale (considered as the gold standard) analysed videos of 40 cattle previously subjected to orchiectomy (recorded for each cattle at four predetermined timepoints during the perioperative period) unaware of the videos’ timepoint. They assigned a pain score [ranging from no pain (0) to severe pain (10)] using the Italian version of the scale and verified the need for analgesic treatment for each animal. The obtained scores were subjected to psychometric validity, responsiveness and reliability tests.

Results

The factor analysis of the scale resulted in a one-factor solution. Significant changes in pain scores in response to surgery and analgesics confirmed not only the content and construct validity, but also responsiveness. The agreement between the researcher who developed the original scale and the blinded observers and the correlation between the pain scores determined by the scale and those determined by three classical unidimensional pain scales confirmed criterion and concurrent validity. Internal consistency of the scale was excellent. Inter- and intrarater reliability ranged from moderate to good and from moderate to very good for all scale items, respectively, supporting reproducibility and stability. The cut-off point for rescue analgesia calculated by the receiver operating characteristic curve was > 3.

Conclusions and clinical relevance

The results confirm that the UNESP–Botucatu UCPS-IV appears to be a valid and reliable tool for the assessment of postorchiectomy pain in the bovine species. The determination of a cut-off point for rescue analgesia is also helpful for guiding analgesic therapy.  相似文献   
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