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1.
Field studies were undertaken to explore the weed management strategies for transplanted and direct wet-seeded rice in the Dera Ismail Khan district of North-west Frontier Province, Pakistan. The experimental design was a randomized complete block with a split plot arrangement. The main plots consisted of two planting techniques (transplantation and direct seeding), while weed control practises assigned to the subplots included the use of the granular herbicide Sunstar 15WG (ethoxy sulfuron), Machete 60EC (butachlor), conventional hand weeding, and the weedy check (untreated control). Data were recorded on weed dynamics and the agronomic parameters of the rice crop. Economic analyses on the data were also run. The weed density and biomass were lower in the transplantation plots than the direct-seeding plots. The herbicides ethoxy sulfuron and butachlor reduced the density over the weedy check, with a density comparable to hand weeding in 2002, but slightly higher in 2003. As a result of weed management by hand weeding and herbicides, the paddy yield and its components were significantly higher for the transplanted method compared to the direct-seeded method. The comparable yield of herbicides with hand weeding offers an option for the use of herbicides as an alternative management tool. In light of our findings, it is concluded that for good economic returns, rice crops may be transplanted rather than direct-seeded. The herbicides ethoxy sulfuron and butachlor offer a weed control cover comparable with hand weeding under the transplantation method, while butachlor is good for controlling weeds even under the direct-seeded conditions in the agroclimatic conditions of the area.  相似文献   
2.
Assessment of spleen size using the ultrasonography has become a standard practice in human. However, the assessment is not established method in experimental animals. To establish the index to assess the spleen size using ultrasonography, we measured the cross-section image of rabbit spleen during endotoxin shock. The image of the cross-section was appeared as triangle, and the height of the triangular image was defined as the spleen index. This spleen index showed strong correlation with the spleen weight. In conclusion, this method is suitable for observation of changes in rabbit spleen size and may reduce the number of rabbit in the longitudinal studies.  相似文献   
3.
In the present study, we developed a larval anchovy growth model in relation to sea temperature and food availability via food consumption and metabolic process terms, based on biological data from previous laboratory experiments and field surveys from 2003 to 2006 in Hiuchi-nada Sea, central part of Seto Inland Sea, Japan. To investigate when food shortage for larval anchovy and then recruitment failure occur in Hiuchi-nada Sea, anchovy food requirements were estimated by using the growth model, and we compared the food requirement with anchovy food availability. We applied an estimation method for growth model parameters, Hewett?CJohnson p and Q 10, by minimizing the sum of squares of difference between mass-specific growth rates estimated by the models and those by otolith growth analysis. Parameter p was 0.86, slightly higher than typical values, and Q 10 was 2.11, close to the value used for the biological model of larval northern anchovy. Food shortage for anchovy larvae did not occur in Hiuchi-nada Sea, although it was indicated that low food availability led to a low reproductive success rate. The newly developed growth model is considered optimal at present and useful to link environmental conditions and larval growth.  相似文献   
4.
The influence of the season on serum vitamin A, E and beta-carotene concentrations was studied in Japanese Black breeding cattle. Blood samples were collected from 13 cows once a month for a year to determine the serum vitamin concentrations. Mean serum concentrations (+/- SE) of retinol, alpha-tocopherol and beta-carotene were 21.3 +/- 0.5 microg/dl (range 9.9 to 44.9), 215.9 +/- 8.0 microg/dl (range 59.7 to 551.6) and 67.3 +/- 5.1 microg/dl (range 10.6 to 425.2), respectively. All these concentrations were lower than the recommended levels. Serum retinol and alpha-tocopherol concentrations in summer were lower than those in winter. These results suggest that the vitamin A, E and beta-carotene status of Japanese Black breeding cows is inadequate, and feeding high quality forages or dietary vitamin supplementation during summer should be recommended.  相似文献   
5.
Seed germination and respiratory metabolism under aerobic and anaerobic conditions were studied in the flooding-tolerant and flooding-susceptible varieties of Echinochloa crus-galli with an identical genome and common ancestry . In the flooding-tolerant E. crus-galli var. formosensis , the seeds imbibed under nitrogen could germinate and exhibited an I/N quotient > 0.6. They accelerated glycolysis and concomitantly produced large and equimolar quantities of carbon dioxide and ethanol, suggesting that the seeds of this variety showed operation of the Pasteur effect and respired through alcohol fermentation under anaerobic conditions. The seeds excreted most of the toxic fermentation product. In contrast, the seeds of the flooding-susceptible E. crus-galli var. praticola were capable of germinating only under aerobic conditions through the conventional aerobic respiration and were unable to anaerobically respire to germinate through alcohol fermentation regardless of the presence of both sufficient alcohol dehydrogenase activity and a high redox charge of the pyridine nucleotides.  相似文献   
6.
Summary Specimens of four commercially produced particleboards were exposed to various accelerated aging treatments: 1) 6-cycle ASTM D-1037 exposure, 2) 6-cycle WCAMA exposure, 3) BS 5669 test, 4) cyclic soak-dry test, and 5) cyclic boil-dry test. Thickness swelling (TS) and internal bond strength (IB) were measured after each step of each cycle. Phenol and phenol (face)/isocyanate (core)bonded boards are more durable than urea and melamine urea bonded boards. The effect of treatment 1) is most severe on TS and IB retention, followed in order by treatments 2), 5), 4) and 3). When the value of springback reached about 35%, IB became equal to zero.  相似文献   
7.
Thirty-eight Aerococcus viridans isolates were obtained from milk from 478 cows with clinical mastitis in a farm during the periods between November 2011 and February 2012, and between December 2012 and March 2013. Additional isolates were obtained from processed manure (a mixture of composted manure, straw and hydrated lime) and bedding materials. The processed manure was later used to cover the floor of the stalls in barns as bedding materials. The temperatures recorded in the composted and processed manure were not as high as those generally observed during satisfactory composting. To reveal the association of A. viridans in manure-related products with intramammary infection in cows, isolates were characterized by their DNA fragment patterns as determined by pulsed-field gel electrophoresis (PFGE) and antimicrobial susceptibility testing. Isolates obtained from milk, processed manure and bedding materials had identical DNA fragment patterns. Antimicrobial susceptibilities were determined for 29 isolates from milk, processed manure and bedding materials. Of these, 26 (89.7%) were resistant to clindamycin, whereas virtually all the isolates were susceptible to 12 other antimicrobials including cefalosporins that have been used to treat bovine mastitis in Japan. In vitro, three A. viridans isolates from milk and an isolate from processed manure survived for 3 hr in Good’s buffer (pH 9) at high temperature (50°C). The results suggest that the processed manure and bedding materials in this farm were possible sources of A. viridans that caused infection in the cows with mastitis.  相似文献   
8.
Plesiomonas shigelloides is a causal agent of gastroenteritis, sepsis and meningitis in humans. We examined the prevalence of P. shigelloides among great cormorants (Phalacrocorax carbo hanedae) in Japan and the antimicrobial susceptibility of isolates. P. shigelloides was isolated from 33 (47.8%) of 69 fecal samples from great cormorants in 2014. All 33 isolates were subjected to antimicrobial susceptibility testing using broth microdilution methods, which showed resistance to ampicillin (31 isolates, 93.9%), tetracycline (two isolates, 6.1%) and trimethoprim (one isolate, 3.0%). The high prevalence of P. shigelloides in the great cormorants implicates the possible microbiological risk to public health.  相似文献   
9.
Kiwifruit (Actinidia deliciosa and Actinidia chinensis) is allergenic to sensitive patients, and, under Japanese regulations, it is one of the food items that are recommended to be declared on food labeling as much as possible. To develop PCR-based methods for the detection of trace amounts of kiwifruit in foods, two primer pairs targeting the ITS-1 region of the Actinidia spp. were designed using PCR simulation software. On the basis of the known distribution of a major kiwifruit allergen (actinidin) within the Actinidia spp., as well as of reports on clinical and immunological cross-reactivities, one of the primer pairs was designed to detect all Actinidia spp. and the other to detect commercially grown Actinidia spp. (i.e., kiwifruit, Actinidia arguta, and their interspecific hybrids) except for Actinidia polygama. The specificity of the developed methods using the designed primer pairs was verified by performing PCR experiments on 8 Actinidia spp. and 26 other plants including fruits. The methods were considered to be specific enough to yield target-size products only from the target Actinidia spp. and to detect no target-size products from nontarget species. The methods were sensitive enough to detect 5-50 fg of Actinidia spp. DNA spiked in 50 ng of salmon testis DNA used as a carrier (1-10 ppm of kiwifruit DNA) and 1700 ppm (w/w) of fresh kiwifruit puree spiked in a commercial plain yogurt (corresponding to ca. 10 ppm of kiwifruit protein). These methods would be expected to be useful in the detection of hidden kiwifruit and its related species in processed foods.  相似文献   
10.
The ability to discriminate local stocks of Japanese anchovy Engraulis japonicus was assessed based on data from four elements (K, Na, P, and Sr) using an electron probe micro analyzer (EPMA) and data from three elements (Ba, Mn, and Sr) using inductively coupled plasma mass spectrometry (ICP-MS) from the otoliths of 40 anchovy (23.6–47.0 mm body length). Anchovy were caught at three sites (Aki-nada, Hiuchi-nada, and Osaka Bay) in the Seto Inland Sea, and one site (Kuroshio extension) in the Pacific Ocean in 2002. In order to discriminate different spawning grounds, EPMA data from the core portion (from core to 30 μm in the core-posterior axis) were used. Results showed that it was difficult to discriminate between the Seto Inland Sea and the Pacific anchovy by EPMA data. Conversely, it was possible to discriminate between the Seto Inland Sea and the Pacific anchovy by ICP-MS data from bulk otoliths. Our results showed that Mn contents of otoliths using ICP-MS discriminate between spawning grounds most, and Ba and Sr discriminate less. The difference in elemental compositions in anchovy otoliths between the Seto Inland Sea and the Pacific Ocean might be reflected by cumulative experienced elemental composition of ambient sea water during life history between the Seto Inland Sea and the Pacific anchovy.  相似文献   
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