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181.
Wheat grain hardness is one of the most important phenotypes related to milling, baking and noodle making. Either a mutation of the Puroindoline-a (Pina) gene or Puroindoline-b (Pinb) gene results in hard grain texture. A deletion mutation of Pina (Pina-D1b) is widely distributed among common wheat cultivars. Although North/South American and Australian cultivars and their descendants have a 15-kbp deletion in common, two new types of deletion mutation were found among Asian wheat cultivars. A 4.4-kbp deletion was found in one Korean and two Chinese wheat cultivars beginning at position +371 within the Pina coding region. The other, a 10.4-kbp deletion, was found in three Chinese and nine Japanese wheat cultivars, including five Japanese landraces, beginning at position −5112. It caused the deletion of the full-length Pina gene. These findings suggest that Asian wheat cultivars are genetically distinct from those in other regions. The 4.4-kbp and 10.4-kbp deletion mutants were designated as Pina-D1r and Pina-D1s, respectively.  相似文献   
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ObjectiveTo describe the hypnotic effects of a single bolus dose of propofol in Japanese macaques, and to develop a pharmacokinetic model.Study designProspective experimental trial.AnimalsFour male macaques (5-6 years old, 8.0-11.2 kg).MethodsThe macaque was restrained and 8 mg kg?1 of propofol was administrated intravenously at 6 mg kg?1 minute?1. Behavioural changes without stimuli (first experiment) then responses to external stimuli (the second experiment) were assessed every 2 minutes for 20 minutes. Venous blood samples were collected before and at 1, 5, 15, 30, 60, 120 and 210 minutes after drug administration, and plasma concentrations of propofol were measured (third experiment). Pharmacokinetic modelling was performed using NONMEM VI.ResultsMacaques were recumbent without voluntary movement for a mean 14.0 ± 2.7 SD (range 10.5-16.2) or 10.0 ± 3.4 (7.2-14.5) minutes and recovered to behave as pre-administration by 25.1 ± 3.6 (22.1-30.1) or 22.2 ± 1.5 (21.1-24.3) minutes after the end of propofol administration without or with stimuli, respectively. Respiratory and heart rates were stable throughout the experiments (28-68 breaths minute?1 and 72-144 beats minute?1, respectively). Our final pharmacokinetic model included three compartments and well described the plasma concentration of propofol. The population pharmacokinetic parameters were: V1 = 10.4 L, V2=8.38 L, V3=72.7 L, CL1= 0.442 L minute?1, CL2= 1.14 L minute?1, CL3= 0.313 L minute?1, (the volumes of distribution and the clearances for the central, rapid and slow peripheral compartments, respectively).ConclusionsIntravenous administration of propofol (8 mg kg?1) at 6 mg kg?1 minute?1 to Japanese macaques had a hypnotic effect lasting more than 7 minutes. A three-compartment model described propofol plasma concentrations over more than 3 hours.Clinical relevanceThe developed pharmacokinetic parameters may enable simulations of administration protocols to maintain adequate plasma concentration of propofol.  相似文献   
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Coronatine (COR) functions as a virulence factor in the interaction of Pseudomonas syringae pv. tomato strain DC3000 with tomato and Arabidopsis. COR consists of two moieties, coronafacic acid (CFA) and coronamic acid (CMA). Both COR and CFA function as structural and functional analogues of jasmonic acid (JA) and related signaling compounds such as methyl jasmonate (MeJA) and JA-isoleucine (JA-Ile). The precise function of COR and whether MeJA functions as an analogue of COR in disease development are not known. In this study, we analyzed whether the COR-defective mutant DB29, which is a CFA CMA mutant of DC3000, could be complemented for virulence via the exogenous application of COR, CFA, or MeJA. When tomato seedlings were inoculated with DB29 and supplemented with exogenous COR, the DB29 population multiplied in tomato seedlings and induced disease phenotypes similar to wild-type DC3000. Although the addition of exogenous MeJA or CFA enhanced the multiplication of DB29, wild-type disease phenotypes could not be restored with these compounds. Furthermore, inoculation of DB29 along with exogenous COR, but not MeJA or CFA, suppressed the expression of defense-related genes and increased the accumulation of reactive oxygen species, which are associated with severe chlorosis. Taken together, our results suggest that although COR targets the jasmonate pathway by mimicking JA, the function of COR in disease development is distinctly different from MeJA or CFA.  相似文献   
184.
Objective To evaluate the sedative effects of medetomidine, and a medetomidine–midazolam combination, in Japanese macaques and the antagonism of medetomidine–midazolam with atipamezole. Study design Prospective randomized study. Animals Thirteen healthy Japanese macaques between 3 and 21 years old and weighing between 4.3 and 15.1 kg. Methods Medetomidine (120 µg kg?1) alone or a medetomidine (30 µg kg?1) plus midazolam (0.3 mg kg?1) mixture were injected intramuscularly in the hind limb of 12 animals (n = 6 for each group) and their effects, particularly behavioural changes, response to external stimuli, sedative onset time, time to lateral recumbency and time in lateral recumbency, were monitored for 120 minutes. Another group (n = 7) were given medetomidine–midazolam and injected 30 minutes later with atipamezole (120 µg kg?1). Behavioural changes and responses to external stimuli were assessed as before. Results Animals given medetomidine became sedated but could be aroused by external stimuli. Despite the lower (25%) dose of medetomidine involved, the effects of medetomidine–midazolam were more marked. Macaques given this combination became sedated in 4 ± 2 minutes (mean ± SD) and remained unresponsive to external stimuli for at least 60 minutes. Five out of six macaques became laterally recumbent for 74 ± 37 minutes. Intramuscular atipamezole effectively reversed sedation, shortening the arousal and total recovery time. The recovery from sedation was rapid and smooth, being completed 19 ± 11 minutes after antagonism. Conclusions The medetomidine–midazolam combination described provided useful chemical restraint and may prove useful in macaques undergoing some experimental, diagnostic or therapeutic procedures. The use of atipamezole as an antagonist increases the value of this technique in macaques.  相似文献   
185.
Raccoons (Procyon lotor), which have recently become feral in Japan, were examined for the presence of Babesia microti-like parasites. Out of 372 raccoons captured in the west-central part of Hokkaido, 24 animals with splenomegaly were selected and tested by nested PCR targeting the babesial 18S rRNA gene. B. microti-like parasites were detected in two of the 24 individuals, and their DNA sequences were identical to that of the B. microti-like parasite reported from raccoons in the United States, suggesting that the parasites were probably imported into Japan and that the life cycle of the parasite has already been established in the country. The potential risk of this B. microti-like parasite spreading among dogs and foxes in Japan will need to be carefully monitored, as parasitization by phylogenetically very close parasites has been reported from such animals.  相似文献   
186.
Our previous report demonstrated that small wild rodents in Japan harbored two types of novel Babesia microti-like parasites (Kobe and Hobetsu types), but not the type widely distributed throughout the temperate zones of North American and Eurasian Continents (U.S. type). In this study, we surveyed small wild mammals collected at various places in the northern part of Japan, seeking for U.S.-type B. microti. A total of 197 small mammals comprising 10 species, Apodemus speciosus, A. argenteus, Clethrionomys rufocanus, C. rutilus, Eothenomys andersoni, Microtus montebelli, Tamias sibiricus, Sorex unguiculatus, S. caecutiens, and Urotrichus talpoides, were examined. Babesia parasites were detected in A. speciosus, C. rufocanus, C. rutilus, M. montebelli, S. unguiculatus, and S. caecutiens by microscopy of blood smears and by PCR targeting babesial nuclear small-subunit rRNA (rDNA) and beta-tubulin genes. Inoculation of their bloods into experimental animals gave rise to 23 parasite isolates, which included 16 from A. speciosus, 4 from C. rufocanus, and 1 each from C. rutilus, M. montebelli and S. unguiculatus. Sequencing analyses of their rDNA and beta-tubulin genes revealed that, of the 23 isolates, 20 and 3 were of Hobetsu and U.S. types, respectively. The U.S.-type B. microti strains isolated in Japan, however, were distinguishable from the isolates in the United States when their beta-tubulin gene sequences and antigen profiles in Western blots were compared. We conclude that U.S.-type B. microti exists in Japan although it has been genetically and antigenically diversified from that distributed in the United States. The results also suggest that not only rodents, but also some insectivores may serve as reservoirs for the agent of human babesiosis.  相似文献   
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