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61.
The study aimed at identifying the occurrence of hydatidosis in slaughter buffaloes and helminth eggs, particularly Taenia spp. eggs in stray dogs' fecal samples in Kathmandu Valley, Nepal. The study period was from November, 2004 to April, 2005. A total of 500 buffalo carcasses in a slaughterhouse, at the riversides and individual butchers'sites were examined for the presence of hydatid cysts. The cyst fluid was collected and microscopically examined to determine if it was fertile or not. Of the 500 carcasses examined, 10.6% had hydatid cysts. Specifically, the slaughterhouse carcasses had a 6.7% occurrence of hydatid cysts, whereas those examined at riversides and individual butcher places had 10.0% and 12.7%, respectively. Distributions of the hydatid cysts by specific organs showed single occurrence of 6.4% in lungs, 2.4% in livers and 1.8% in both, livers and lungs. In a total of 53 infected buffaloes, 58.5% were fertile and 41.5% sterile cysts. Overall, 366 faecal samples from stray dogs were collected around buffaloes slaughtering areas (slaughterhouse and individual butcher places), riversides, garbage sites and temple sites. These samples were examined by formalin-ether concentration technique to investigate the presence of different helminth eggs. The total prevalence of Taenia, hookworms, Trichuris/Capillaria,Toxocara, Spirometra and Physaloptera eggs were 12.8%, 18.3%, 19.1%, 12.8%, 1.4% and 1.9%, respectively.  相似文献   
62.
Dairy production in Uganda is pasture-based and traditional Ankole cattle make up 80% of the cattle herd, reared in both pastoral and agro-pastoral ecological zones. Regardless of the zone, milk quality is lowest in production basin during the dry season when ambient temperatures are highest and water is scarce. Poor hygiene and quality management contributed to the deterioration of raw milk quality during its storage and delivery to the final consumer, and concealed the seasonal effect when milk reached urban consumption areas. Poor milk quality is a challenge for the Ugandan Dairy Development Authorities who wish to make the milk value chain safe. This study provides baseline information for the implementation of an HACCP-based system to ensure the hygienic quality of milk from the farm to the market place.  相似文献   
63.
The study was conducted to investigate the effects of feeding different levels of dried cassava leaves at 0%, 20%, 40% and 60%, respectively, using guinea grass as basal feed, on the haematological and serum biochemical parameters of West African Dwarf (WAD) goats. The study lasted for 116 days during which haematological and serum biochemical parameters were monitored in 40 male goats before and after, using a completely randomized design. At the start of the experiment, packed cell volume (PCV) ranged from 21.5% to 25.5% while haemoglobin concentration (Hb) and RBC significantly (P < 0.01) ranged from 7.3 to 8.6 g/dl and 10.4 to 13.2 × 1012/l, respectively. White blood cells reduced significantly (P < 0.05)) from 16.4 to 11.7 × 109/l) as dried cassava leaves increased in the diets. At the end of the trial, there was a slight increase in the values of PCV and Hb in the diets (P > 0.05). Lymphocyte reduced significantly (P < 0.05) from 50.0% to 63.5% in the diets. Neutrophils, however, increased (P > 0.05) at the 0% to 40% levels and reduced at the 60% level of dried cassava leaves inclusion. At the start of the experiment, values for glucose significantly (P < 0.05) ranged from 40.1 to 56.0 mg/dl. Total protein and albumin values ranged significantly (P < 0.05) from 56.0 to 68.5 g/dl and 30.6 to 38.4 g/dl, respectively. At the end of the experiment, serum creatinine increased significantly (P < 0.05) as the level of dried cassava leaves increased from 0% to 60% in the diets. The study revealed that inclusion of dried cassava leaves in the diets of West African Dwarf goats had no deleterious effects on the haematological and serum biochemical parameters of WAD goats and could therefore be included in ruminant diets up to 60%.  相似文献   
64.
Background:Administration of exogenous progesterone (P4) to ewes during the pre-implantation period advances conceptus development and implantation. This study ...  相似文献   
65.
Effect of malathion (organophosphorus insecticide) and endosulfan (organochlorine insecticide) on in vitro LH-induced oocyte maturation was investigated in the oocytes of common carp, Cyprinus carpio. In control incubation, LH at the concentration of 10 μg mL?1 induced 41.2 ± 1.6% of germinal vesicle breakdown (GVBD). When the oocytes were incubated with malathion at the concentrations of 1000, 500, 100, and 50 ppb together with LH it could induce only 13.4 ± 0.4, 14.0 ± 1.0, 12.9 ± 3.5, and 18.1 ± 3.9% of GVBD, respectively. Similarly, when the oocytes were incubated with endosulfan at the concentrations of 0.5, 0.1, 0.05, and 0.01 ppb together with LH, it induced only 12.8 ± 1.6, 8.8 ± 1.2, 20.9 ± 2.1 and 26.0 ± 2.2% of GVBD, respectively. The significance of the result obtained were discussed on the basis of available literature.  相似文献   
66.
Efficient tandem polymer solar cells fabricated by all-solution processing   总被引:1,自引:0,他引:1  
Tandem solar cells, in which two solar cells with different absorption characteristics are linked to use a wider range of the solar spectrum, were fabricated with each layer processed from solution with the use of bulk heterojunction materials comprising semiconducting polymers and fullerene derivatives. A transparent titanium oxide (TiO(x)) layer separates and connects the front cell and the back cell. The TiO(x) layer serves as an electron transport and collecting layer for the first cell and as a stable foundation that enables the fabrication of the second cell to complete the tandem cell architecture. We use an inverted structure with the low band-gap polymer-fullerene composite as the charge-separating layer in the front cell and the high band-gap polymer composite as that in the back cell. Power-conversion efficiencies of more than 6% were achieved at illuminations of 200 milliwatts per square centimeter.  相似文献   
67.
68.
Savannas worldwide are vital for both socioeconomic and biodiversity values. In these ecosystems, management decisions are based on the perception that wildlife and livestock compete for food, yet there are virtually no experimental data to support this assumption. We examined the effects of wild African ungulates on cattle performance, food intake, and diet quality. Wild ungulates depressed cattle food intake and performance during the dry season (competition) but enhanced cattle diet quality and performance during the wet season (facilitation). These results extend our understanding of the context-dependent-competition-facilitation balance, in general, and are critical for better understanding and managing wildlife-livestock coexistence in human-occupied savanna landscapes.  相似文献   
69.
70.
There is increasing community awareness of the potential environmental risks posed by Cu-based fungicide use, which is placing increasing pressure on governments and industry to undertake risk minimisation action. However, if there is going to be a widespread move away from the use of Cu-based fungicides, logically there needs to be assurance that the alternatives pose a lower environmental risk. To that end, this study compared the effect of copper hydroxide, captan and trifloxystrobin on soil enzymatic (phosphomonoesterase and urease) activity. Compared to an untreated control, copper did not inhibit either enzyme activity, even at the highest dose used in the study (156 mg/kg). At their respective high doses, captan (96 mg/kg) and trifloxystrobin (144 mg/kg) did not cause inhibition of phosphomonoesterase activity but did inhibit urease activity. Consequently, the results from this study suggest that the copper hydroxide alternatives, captan and trifloxystrobin, do not pose a short-term risk to P cycling processes in soil, although the results do suggest that these two are more toxic than copper hydroxide to N cycling processes in soil. Moreover, captan and trifloxystrobin compounds are unlikely to pose a long-term risk to soil microbial function as they are unlikely to persist in soil at concentrations found to cause an adverse effect on urease activity. Nonetheless, the potential disruption to N cycling processes needs to be recognised and consideration given to limiting the annual applications of these fungicides, particularly around the timing of repeat fungicide applications, to prevent accumulation of the fungicides in surface soils.  相似文献   
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