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31.
Freeze-drying (lyophilization) has been proposed as an alternative method for sperm preservation to overcome the disadvantages of the current cryopreservation method such as the high maintenance cost of frozen stocks, the problems associated with transportation of frozen materials and the potential risk of total loss of the frozen stock. Since freeze-dried spermatozoa after rehydration lose their motility, which is an essential requirement to complete physiological fertilization, a relatively difficult microinsemination technique must be applied to rehydrated spermatozoa. Theoretically, it has been supposed that freeze-dried spermatozoa could maintain their functions and abilities to interact with the oocyte cytoplasm after prolonged storage at refrigerator temperature. However, sufficient yield of transferable blastocysts and production of live offspring derived from freeze-dried sperm samples are still subjects to be challenged and overcome in large domestic species.  相似文献   
32.
Tropical Animal Health and Production - In Egypt, inadequate information on prevalence and epidemiology of caprine mastitis is available. This study was designed to investigate prevalence and...  相似文献   
33.
Water, Air, &; Soil Pollution - This study had been carried out between October 1992 and February 1994 in Köyce?iz Lagoon System (KLS) which is aspecially protected area (SPA)....  相似文献   
34.
The purpose of the study reported here was to discuss the level of intelligibility of three-dimensional computed tomography (3D-CT) images of clinical patients for persons who are lacking veterinary knowledge. 143 undergraduate students were participated in this study. They were entirely unfamiliar with veterinary anatomy. A survey was conducted using the visual analog scale method with a focus on the level of intelligibility of the 3D-CT images compared to that of the two-dimensional CT images or radiographs. As a result, the mean value of the intelligibility of the 3D-CT image was 88.4 ± 17.8 points out of 100 points. In clinical cases, it is very difficult for pet owners lacking veterinary knowledge to understand the clinical status of their pets even with explanations using illustrations, radiographs, and transverse CT images. It is considered that better informed consent and patient satisfaction will be obtained provided veterinarians make an effort towards intelligible patient education by using 3D-CT images.  相似文献   
35.
High‐protein distillers dried grains (HPDDG) is a co‐product of ethanol production that uses prefractionation technology. A 70‐day growth trial was conducted to investigate the effect of partial replacement of dietary soybean meal by high‐protein distiller's dried grains (HPDDG) with protease enzyme supplementation (PROXYM ULTRA®) on growth performance, physiological parameters and histological changes of the intestine of European sea bass, Dicentrarchus labrax fingerlings. The results indicated that increased dietary HPDDG levels up to 50% of HPDDG supplemented with protease significantly increases growth performance and feed utilization and improved FCR of sea bass. In addition, replacement of SBM by HPDDG supplemented with protease enhanced feed intake efficiency and the health status of fish. Haematology and serum biochemistry (haemoglobin (Hb)), red blood cells (RBCs), white blood cells (WBCs) and humeral immune parameters including total protein, globulin, cholesterol, lysozyme activity and total antioxidant capacity significantly increased with increase in HPDDG supplemented with protease in the diets. Results of this study indicated that HPDDG supplemented with protease is a good alternative protein source for aquaculture feed and can be included up to 50% as a replacement of SBM without compromising growth performance and physiological parameters of sea bass.  相似文献   
36.
The present study was conducted to evaluate the adverse effects of an interaction between low levels of dietary aflatoxins (AF) and Eimeria tenella infection on broiler chicks. A set of 1-day-old chicks were raised for 35 days in the following groups: a control group, a group fed AF, a group fed AF and inoculated with E. tenella (AF + E.ten), and a group inoculated with E. tenella alone. AF in the contaminated diet were given at 200 ppb starting from the seventh day after hatching while E. tenella was inoculated at a dose of 5 × 104 sporulated oocysts per chick at the 14th day after hatching. Worsened performance traits and high mortality were all observed in the treated birds, particularly the AF + E.ten group. Lesion scores and oocyst outputs were not different within groups. Chickens fed with AF had significantly increased serum ALT and ALP activities as well as decreased albumin content. They also showed hepatomegaly, hepatocytic vacuolation and necrosis, an atrophied bursa of Fabricius, and a thymus with tissue depletion. E. tenella-infected broilers displayed a significant reduction in packed cell volume, hemoglobin content and lymphocyte percentage, and showed hemorrhagic typhlitis. The deficits in hepatic function and hematologic parameters as well as the gross pathological, and histopathological changes, were more common and more severe in the group that was exposed to both aflatoxicosis and coccidiosis than in the groups exposed to either treatment alone. Thus, the combination of aflatoxicosis and E. tenella infection may influence the course of coccidial infection due to additive effects.  相似文献   
37.
The question of how Sarcocystis neurona is able to overcome species barrier and adapt to new hosts is central to the understanding of both the evolutionary origin of S. neurona and the prediction of its field host range. Therefore, it is worth reviewing current knowledge on S. neurona host specificity. The available host range data for S. neurona are discussed in relation to a subject of evolutionary importance—specialist or generalist and its implications to understand the strategies of host adaptation. Current evidences demonstrate that a wide range of hosts exists for S. neurona. This parasite tends to be highly specific for its definitive host but much less so for its intermediate host (I.H.). The unique specificity of S. neurona for its definitive host may be mediated by a probable long coevolutionary relationship of the parasite and carnivores in a restricted ecological niche ‘New World’. This might be taken as evidence that carnivores are the ‘original’ host group for S. neurona. Rather, the capacity of S. neurona to exploit an unusually large number of I.H. species probably indicates that S. neurona maintains non-specificity to its I.H. as an adaptive response to insure the survival of the parasite in areas in which the ‘preferred’ host is not available. This review concludes with the view that adaptation of S. neurona to a new host is a complex interplay that involves a large number of determinants.  相似文献   
38.

Abiotic stress has a negative impact on plant physiology, influencing the overall growth and development of plant crops. Saline stress is one of the most serious environmental issues limiting crop plant production. Biofertilizers are reparative elements used in soil to increase tolerance to salinity and drought stress. We investigated the effect of salinity stress on qualitative and quantitative characteristics of cherry tomato plants (Lycopersicon esculentum cerasiforme) with biofertilizer application 0, 15 and 30 days after transplanting in this study. After different days of transplantation, different levels of salinity (0, 50, 100, and 150?mM) were used with biofertilizer (Azospirillum sp. and Azotobacter sp.) application (0, 15 and 30 days). The salinity (150?mM NaCl) significantly affected the studied variables, which were recorded with minimum levels of leaf area (52.42?cm2), root length (6.54?cm), fresh root weight (13.64?g), yield (6.52 tons/ha), leaf chlorophyll content (36.11?mg/m2) and maximum levels of total soluble solids (TSS, 8.87 °Brix). Control samples had higher leaf area (58.35?cm2), root length (15.23?cm), fresh root weight (17.86?g), yield (9.39 tons/ha), leaf chlorophyll content (44.09?mg/m2), and lower TSS (7.93 °Brix). Plants that received biofertilizer (15 days after transplanting) had higher plant height (73.41?cm), stem diameter (0.74?cm), leaf area (61.16?cm2), root length (15.35?cm), fresh root weight (18.38?g), root dry matter (60.41%), yield (10.43?t/ha), leaf chlorophyll content (42.55?mg/m2), fruit dry matter content (10.12?g), pH 4.52, and TSS (9.30 °Brix). The minimum plant height (51.33?cm), stem diameter (0.55?cm), leaf area (49.60?cm2), root length (7.04?cm), fresh root weight (12.76?g), root dry matter (42.16?g), yield (5.15 tons/ha), leaf chlorophyll content (35.18?mg/m2), fruit dry matter content (6.59?g), pH 4.27 and TSS (7.55 °Brix) were recorded in plants with no application of biofertilizer. The present study revealed that most growth and quality variables were negatively affected by salinity except for TSS, which showed positive effect with application of 150?mM of NaCl. Biofertilizer application at 15 days significantly influences the quantitative and qualitative attributes of cherry tomato under different levels of salinity.

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39.
Reforestation of woodlands with native species in the Erzgebirge, where large-scale deforestation has been caused by severe air pollution, was investigated. In an experiment, three tree species (Norway spruce, rowanberry, and birch) were studied with regard to fencing (no protection versus protection against game browsing) and site preparation techniques with eight levels: a control and seven amelioration techniques (soil cultivation, weed control, liming, and their combinations). Four criteria, survival, growth, production, and vitality, were used in assessing the success of the plantings. Repeated-measures analyses were performed to examine the development of the young plantations over an observation period of 7 years, and to determine whether this development was dependent on the experimental factors. Spruce showed high survival rates, reasonable growth and production, and good individual vitality. With the exception of survival, birch responded similarly to spruce. The low survival rate of birch resulted from the initial small size of the seedlings. By providing appropriate seedling material, both species could be used for reforestation. Seedlings of rowanberry were unsuccessful due to severe mouse damage, confirming the necessity of rodent control when planting cleared areas with this species is undertaken. Game browsing was not significant. None of the amelioration techniques had a major effect on the studied criteria of the three tree species. Slightly positive effects occurred only when spruce was limed and when birch received soil cultivation. Weed control by scything showed undesirable results, particularly for birch. For reasons of financial thriftiness, none of the amelioration techniques could be justified for the study area.  相似文献   
40.
Growth and biochemical parameters of leaves, flower buds and flowers of olive (Olea europaea L. cv. Chemlali) treated by foliar biofertilization (T0: untreated trees; T1: rich in nitrogen (N), phosphorus (P), potassium (K); T2: rich in calcium (Ca); T3: application of T1 and T2) were analyzed during the flowering stage. The results showed that T1 resulted in higher contents of leaf N, K, and Na. T1 and T3 resulted in an increase of pigment concentration in leaves. All foliar treatments affected negatively the contents of total polyphenols and orthodiphenols in leaves and flower buds. Lower amounts of individual phenolic compounds were detected in the leaves under all foliar bio-fertilizations and in flower buds of olive trees sprayed with T2 and T3. This decrease is explained by the lower enzymatic activity of l-phenylalanine ammonia-lyase. In flowers, T1 exhibits the highest levels of total polyphenols, o-diphenols, and individual phenolic compounds compared to T0.  相似文献   
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