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291.
AIM: To investigate possible relationships between the incidence of lameness in dairy cows, and walking order from the paddock into the milking shed, milking order, and dominance structure in the herd. METHODS: Ten dairy herds from the Taranaki region in New Zealand, with an average herd size of 183 cows, were observed during early, mid and late lactation. Each observation period consisted of five observations within 1 week, totalling 15 observations per farm. Three observers recorded the daily movement of cows between paddocks and the milking shed at each of three different locations. Additionally, the dominance structure of 21 cows per herd, randomly selected at the beginning of the study, was determined at the beginning of each of the three observation periods, on the basis of antagonistic behaviour. RESULTS: Within herds, walking and milking order showed a Kappa value of 0.31, reflecting fair agreement beyond chance. Based on the multivariate model, an increased risk of lameness was found for cows that walked or were milked in the last quarter of the herd (OR=1.8 and 1.5, respectively) compared with animals that walked/were milked in the first three quarters of the herd. The dominance structure of the randomly selected animals remained stable during the course of the lactation. High dominance animals tended to walk at the front of the herd and get milked first, whereas low dominance animals tended to walk at the back of the herd and get milked last. Although lameness was not significantly related to the dominance group, this could have been due to the low power of the study. CONCLUSIONS: The results of the study suggested that there is a relationship between the position of the animal in the herd and the risk of lameness in dairy cows, but that the strength of this relationship varied between herds. CLINICAL RELEVANCE: Walking/milking order was a risk factor for conditions causing lameness in dairy cows, and for the effective management of herd lameness problems it is important for farmers to be aware of this relationship.  相似文献   
292.
OBJECTIVE: To evaluate the historical data, signalment, clinical signs, results of laboratory analyses, treatment, and outcome of horses with small intestinal (SI) volvulus. STUDY DESIGN: Retrospective study. SAMPLE POPULATION: One hundred and fifteen client-owned horses, aged 1 month to 21 years. METHODS: Clinical signs, laboratory data, surgical or necropsy findings, and outcome for horses with SI volvulus were obtained from medical records, identified by computer search and manual review. RESULTS: There was no statistical difference in signalment between cases and the hospital population. Seventy-four percent of horses were >/=3 years. There were considerable variations in clinical signs on admission; high heart rate and signs of severe pain were not consistent features. Examination per rectum identified distended small intestine in only 69% of horses. One hundred horses had surgery, and small intestine resection was performed in 25. Eighty-four horses were recovered from surgery, and 67 horses survived to hospital discharge (80% of horses recovered from surgery, 58% of 115 horses). Forty-eight percent that were ultimately discharged had a post-operative complication and these horses had a longer average stay than horses with no complication (11 days versus 8.9 days). CONCLUSIONS: We identified 115 horses with primary SI volvulus over a 12-year period. We found that the population of horses with this lesion was older than has previously been reported and that the prognosis for post-operative survival to hospital discharge is good (80%). Post-operative complications were common, and affected approximately half the horses that were ultimately discharged from the hospital. CLINICAL RELEVANCE: This information may aid diagnosis and prognosis and guide decision making for horses with this condition.  相似文献   
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294.
AIM: To assess the consequences of anthelmintic resistance on commercial sheep farms on liveweight (LW) gains and susceptibility to diarrhoea of growing lambs. METHODS: Five farms with a history of resistance to benzimidazole drenches were selected. On each farm, 150 ewe lambs were randomly allocated to 1 of 3 treatment groups (n=50). Group 1 was treated 5 times at 28-day intervals with oxfendazole (to which nematode resistance had been demonstrated); Group 2 was treated 5 times at 28-day intervals with levamisole or levamisole + oxfendazole (to which nematode resistance had not been demonstrated) and; Group 3 was treated with a combination of slow-release albendazole capsules and oral moxidectin (intended to totally suppress nematode infection). Differentiated faecal egg counts (FECs), FEC reduction tests (FECRT), LW gain and degree of faecal soiling around the breech (dag scores) were determined and compared between groups. RESULTS: Pre-treatment FECs in Group 1 were similar to or slightly lower than those of Group 2. Efficacy of oxfendazole in Group 1 varied between farms and over time within farms, the reduction in FECs after treatment varying from 0% to 95%. The genera identified as resistant on each farm also varied over time. Lambs from Group 3 had lower FECs, lower dag scores and higher growth rates than lambs from Group 2, which in turn had higher LW gains than lambs from Group 1. The overall LW gains during the 5 months of the study were 7.03+/-0.27 kg for Group 1, 8.33+/-0.27 kg for Group 2, and 9.91+/-0.31 kg for Group 3 (mean+/-SEM; means differed significantly from each other, p<0.01). CONCLUSIONS: The decrease in growth rates associated with the continued use of an incompletely effective anthelmintic were surprisingly small in situations where all lambs grazed together.  相似文献   
295.
The morphology and histology of the cetacean adrenal gland are poorly understood. Therefore, this study examined 32 pairs of adrenal glands from 18 pan-tropical spotted dolphins (Stenella attenuata) and 14 spinner dolphins (Stenella longirostris). In both species, the cortex was pseudolobulated and contained a typical mammalian zonation. Medullary protrusions (0-3 per section) and a medullary band were identified in both species. For S. attenuata, no statistical differences were found in the cortex to medulla (CM) ratio or the percent cross-sectional area (PCA) of the adrenal glands compared with sex or sexual maturity. The mean CM ratio for S. attenuata was 2.34 and the PCA was 64.4% cortex, 29.4% medulla and 6.2%'other'. 'Other' indicates blood vessels, connective tissue and the gland capsule itself. For S. longirostris, there was no statistical difference in the CM ratio compared with sexual maturity. However, a statistical difference was found between the CM ratio and sex, suggesting sexual dimorphism (female CM ratio = 2.46 and males = 3.21). No statistical differences were found in the PCA of S. longirostris adrenal glands by sexual maturity. However, a statistical difference was found between the PCA by sex. Female S. longirostris adrenal glands consisted of 65.0% cortex, 27.3% medulla and 7.7% 'other', whereas male adrenal glands consisted of 71.7% cortex, 22.7% medulla and 5.6% 'other'.  相似文献   
296.
Canine atopic dermatitis (CAD) is manifested by pruritus and inflammation of the skin, and most affected dogs have specific IgE against environmental allergens. Our aim was to evaluate whether in Sweden the incidence of CAD varies spatially, and to investigate possible environmental causes of such variation in a longitudinal study of CAD incidence among insured Swedish dogs. The dataset consisted of >220,000 individuals which had been covered by an insurance plan between January 1, 1995 and December 31, 2002. Out of these, 1235 CAD cases were identified and matched to postal-code areas based upon the address of the owner. Environmental risk factors we considered included averages of long-term annual rainfall, and of January and July temperatures. Initial visualization of the incidence rate of CAD (cases/dog-years at risk) expressed as empirical Bayes smoothed spatial rates indicated geographic variation. Moran's I, adjusted for population at risk, revealed significant global clustering. Both the spatial scan statistic and a local indicator of spatial autocorrelation revealed a higher incidence of CAD in the major cities. In a Poisson-regression model (with a spatial covariance structure), the incidence of CAD increased with increasing human population density, increasing average annual rainfall, living in the southern half of Sweden, and having a veterinary dermatologist in the county.  相似文献   
297.
A propeller-wash bead filter (PWBF) and a fluidized sand filter (FSF) on a 28 m3 recirculating system stocked with tilapia maintained favorable water quality at five different feed rates, ranging from 0.9 to 4.5 kg feed per day. TAN removal rates ranged up to about 200 g TAN/m3 of media per day for each of the units. Peak rates of 244 g TAN/m3 of media per day were observed when the recirculating flow was boosted by 20%. Roughly 75% of the removal was accomplished by the fluidized sand filter an observation that is consistent with the difference between the fluidized sand filter volume (0.92 m3) and the bead filter media volume (0.28 m3). The bead filter's primary function was clarification. At the highest daily feed load, over 570 g dry weight of solids were removed during each daily bead filter backwashing event. A 20% increase in flow, at the same daily feed rate, improved solids removal to over 670 g dry weight per bead filter backwash event. The PWBF and FSF combination provided suitable water quality for fish production; however, further increases in feed loading were limited by carbon dioxide buildup and oxygen limitations.  相似文献   
298.
To obtain the basic information on human exposure to mercury (Hg) due to gold mining activities in Amazon, total mercury (T-Hg) and methylmercury (MeI Ig) were determined for human hair, blood and/or urine samples collected from populations living in gold mining area and fishing villages upstream of the Tapajos River basin. Abnormally high levels of T-Hg were observed in hair and blood from all fishing villages investigated and more than 90% of T-Hg was in the form of MeHg in both samples, whereas in goldrnining area the value were much lower and the %MeHg values varied widely (20–100%) with individuals even in blood samples. Urine from gold shop workers contained Hg mostly in inorganic form at 165μg/g creatinine on the average, with the range of 20 to 450μg/g creatinine. A good correlation between Hg in hair and blood was found in fishing villages and the ratios of hair Hg to blood Hg were very close to 250, generally established for MeHg. T-Hg and inorganic Hg levels in urine from gold shop workers were also significantly correlated with inorganic Hg in blood.  相似文献   
299.
The accumulation and transformation of organic matter during soil development is rarely investigated although such processes are relevant when discussing about carbon sequestration in soil. Here, we investigated soils under grassland and forest close to the North Sea that began its genesis under terrestrial conditions 30 years ago after dikes were closed. Organic C contents of up to 99 mg g−1 soil were found until 6 cm soil depth. The humus consisted mainly of the fraction lighter than 1.6 g cm−3 which refers to poorly degraded organic carbon. High microbial respiratory activity was determined with values between 1.57 and 1.17 μg CO2-C g−1 soil h−1 at 22 °C and 40 to 70% water-holding capacity for the grassland and forest topsoils, respectively. The microbial C to organic C ratio showed values up to 20 mg Cmic g−1 Corg. Although up to 2.69 kg C m−2 were estimated to be sequestered during 30 years, the microbial indicators showed intensive colonisation and high transformation rates under both forest and grassland which were higher than those determined in agricultural and forest topsoils in Northern Germany.  相似文献   
300.
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