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321.
Information on the external shape, internal properties and defects of a tree is important for the forest and wood-processing industries. Resin pockets are internal defects, associated with some softwood species, and are especially undesirable in furniture, joinery and veneer products. In this study, we propose a new lower-cost method for measuring tree shape and macroscopic internal characteristics. The objectives of this study were to: (1) design, construct and test a mobile system that can be used in field to obtain a three-dimensional model of a log or tree stem indicating selected macroscopic internal characteristics and (2) to use the system to investigate the occurrence and causes of resin pockets in Pinus patula from the Mpumalanga escarpment in South Africa. In order to establish the cause of resin pocket formation in Pinus patula, four 3-m logs from 24 trees from three compartments were dissected and digitally reconstructed into three-dimensional models. The results from the study suggest that the formation of Type 1 resin pockets in Pinus patula was due to bending stresses caused by wind sway. It was not possible to establish with certainty the cause of Type 2 resin pocket formation. However, there was evidence that damage events, and specifically thinning damage, have been the cause of some of the Type 2 resin pockets observed.  相似文献   
322.
This paper contrasts the perceptions of Canadians who are food-secure with the perceptions of Canadians who are food-insecure through the different meanings that they ascribe to a popular food product known as Kraft Dinner®. Data sources included individual interviews, focus group interviews, and newspaper articles. Our thematic analysis shows that food-secure Canadians tend to associate Kraft Dinner® with comfort, while food-insecure Canadians tend to associate Kraft Dinner® with discomfort. These differences in perspective partly stem from the fact that Kraft Dinner® consumption by food-secure Canadians is voluntary whereas Kraft Dinner® consumption by food-insecure Canadians frequently is obligatory. These differences are magnified by the fact that food-insecure individuals are frequently obliged to consume Kraft Dinner® that has been prepared without milk, a fact that is outside the experience of, and unappreciated by, people who are food-secure. The food-secure perspective influences responses to food insecurity, as Kraft Dinner® is commonly donated by food-secure people to food banks and other food relief projects. Ignorance among food-secure people of what it is like to be food-insecure, we conclude, partly accounts for the perpetuation of local food charity as the dominant response to food insecurity in Canada.  相似文献   
323.
324.
Anabolic steroid implants are routinely used to increase growth performance and profitability; however, there are concerns that the use of implants, particularly those containing trenbolone acetate, may have detrimental effects on carcass quality and beef tenderness. Thus, the objectives of the current study were to determine the effects of various commonly used implant regimens on shear force values, sensory properties, and consumer satisfaction of beef top loin steaks from cattle of Bos indicus influence. Cattle were supplied by producers that agreed to provide sire and dam information in exchange for carcass and sensory data. Steers (n = 2,748) were assigned randomly to one of three implant treatments (12/sire; four steers from each sire were placed into each treatment group): 1) unimplanted controls (n = 1,368); 2) Synovex-S followed by another Synovex-S (n = 660); or 3) Synovex-S followed by Revalor-S (n = 720). Steaks sampled after 3, 7, and 14 d of aging indicated that unimplanted cattle had lower (P < 0.05) Warner-Bratzler Shear force values than those from implanted animals. No differences (P > 0.05) in shear force values were found between the two treatments or the control groups for steaks sampled following a 21-d aging period. Steaks from implanted animals sampled after 3, 7, and 14 d aging were rated lower (P < 0.05) for initial and sustained trained sensory panel tenderness scores. Consumers failed to detect any differences in steak samples related to implant treatment after 7 and 14 d of aging. Consumer education level and family income did not affect overall acceptability (P > 0.10 and 0.18, respectively) or tenderness acceptability (P > 0.11 and 0.68, respectively); however, consumers with postgraduate degrees recorded lower (P < 0.05) overall quality, beef flavor, juiciness, and tenderness scores than consumers in all other education classifications. Additionally, family income had no effect on overall quality (P > 0.21), beef flavor (P > 0.28), juiciness (P > 0.58), or tenderness (P > 0.45) scores. Results indicate that using a moderate implant program in Bos indicus-influenced cattle has no detrimental effects on beef tenderness and consumer acceptability.  相似文献   
325.
Two morbilliviruses were isolated from carcases of Mediterranean monk seals (Monachus monachus) which had died in coastal areas of Greece and Mauritania. They were characterised as being closely related to the previously identified dolphin and porpoise morbilliviruses on the basis of their serological cross-reactivities in immunofluorescence assays, and sequence homologies in their N and P genes. The results suggest that morbilliviruses of aquatic mammals may cross barriers between species of different orders.  相似文献   
326.
The narcotizing potential of various rectified current configurations on Oreochromis mossambicus was investigated. A 50 Hz, 200 Vp. half-wave rectified current, applied for 30 s, was found to be a suitable configuration for electronarcosis.  相似文献   
327.
Spoligotyping was applied to 44 isolates of Mycobacterium bovis obtained from the Canadian province of Manitoba. Isolates were obtained from submissions of elk (n = 16), deer (n = 1), and cattle (n = 27) tissues spanning the period of 1990 to early 2003. Two spoligotype profiles were obtained differing only in the reaction with oligonucleotide number 12. Forty of the 44 isolates (90.9%) hybridized with oligonucleotide 12 (MB-1 type), while the remaining 4 of 44 (9.1%) did not show a signal at position 12 (MB-2 type). Octal codes for these 2 types are 656573377603600 and 656473377603600, respectively. These spoligotypes have not been reported as occurring elsewhere worldwide.  相似文献   
328.
We used positron emission tomography (PET) with [18F]fluoromisonidazole ([18F]FMISO) to study tumor hypoxia in six dogs with spontaneous sarcomas. The tumors were regarded as hypoxic if [18F]FMISO uptake exceeded normal tissue radioactivity by 40% (tumor/muscle ratio > 1.4) or if kinetic analysis indicated a positive [18F]FMISO tissue influx rate (Ki > 0) by a Patlak plot. Using these criteria, we found hypoxia in a fibrosarcoma grade II, an undifferentiated sarcoma, and an ostoeosarcoma, but not in a fibrosarcoma grade I, another osteosarcoma, and a myxosarcoma. In three animals, the tumor oxygen partial pressure (pO2) was also measured invasively using Eppendorf needle electrodes. In these cases, the Eppendorf measurements were confirmed by the [18F]FMISO PET results. In addition, [15O]H2O PET was performed in four dogs in order to assess tumor perfusion. Comparisons of the [18F]FMISO with [15O]H2O PET images in two cases showed that tumor hypoxia occurred in the tumor center with low perfusion, whereas perfusion was heterogeneous in a nonhypoxic tumor.  相似文献   
329.
The objective of this study was to determine the serum pharmacokinetics of terbutaline in healthy cows. In the initial experiment, terbutaline was administered once as an intravenous (i.v.) bolus to 6 near-term pregnant beef cows within 24 h after parturition at a low but therapeutically relevant dose, 5 microg/kg. A 2nd experiment was conducted in the same cows with a higher dose, 0.5 mg/kg, but an otherwise similar experimental design. The serum concentration of terbutaline was determined by means of high-performance liquid chromatography with fluorescence detection in both experiments. After i.v. administration of 0.5 mg/kg, the mean peak serum concentration, residence time, and half-life were 708.22 (standard deviation 509.6) ng/mL, 6.75 (3.6) min, and 6.93 (2.4) min, respectively. The results indicate that terbutaline is rapidly eliminated from the bloodstream after i.v. administration in cattle, falling below the assay's limit of detection 30 min after administration.  相似文献   
330.
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