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Molecular and biological characterization of the begomovirus isolate BR:LNS2:Pas:01, obtained from yellow passionfruit plants in Livramento de Nossa Senhora, Bahia state, Brazil, was carried out. Sequence analysis demonstrated that the BR:LNS2:Pas:01 DNA‐A had highest nucleotide sequence identity with Tomato chlorotic mottle virus (77%) and had five ORFs corresponding to the genes cp, rep, trap, ren and ac4. The DNA‐B had highest nucleotide sequence identity with Tomato yellow spot virus (74%) and two ORFs corresponding to the genes mp and nsp. These identity values indicate that this isolate represents a new begomovirus species, for which the name Passionfruit severe leaf distortion virus (PSLDV), is proposed. Phylogenetic analysis clustered the PSLDV DNA‐A and ‐B in a monophyletic branch with Brazilian tomato‐infecting begomoviruses. The isolate’s host range was restricted to species from the Passifloraceae and Solanaceae. PSLDV‐[BR:LNS2:Pas:01] was capable of forming pseudorecombinants with tomato‐infecting begomoviruses, reinforcing its close relationship with these viruses and suggesting a possible common origin. However, the virus was not capable of infecting tomato.  相似文献   
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Gonadotropin-releasing hormone (GnRH) antagonists are particularly useful when a rapid inhibitory effect on the gonadal axis is required. The aim of this study was to test the efficacy and clinical safety of a low and high dose of the third generation GnRH antagonist, acyline, on pregnancy termination in female dogs. The effect of the antagonist on the progesterone (P4) serum concentration was also described. Twenty-one mid-pregnant bitches were randomly assigned to a single subcutaneous (SC) dose of a placebo (PLACE; n = 7), a low (ACY-L; 110 μg/kg; n = 6) or high (ACY-H; 330 μg/kg; n = 8) dose of acyline. The animals were followed up for 15 days. All ACY treated but no placebo-treated animals terminated their pregnancy by abortion (p < 0.01). The ACY-L and ACY-H groups interrupted their pregnancy 7 ± 1.9 and 6.4 ± 1.3   days after treatment, respectively (p = 0.7). A significant interaction between treatment and day was found (p < 0.01) for P4 serum concentrations when PLACE was compared with both ACY groups. No difference was found for this hormone between both ACY groups (p > 0.05) where P4 diminished throughout the study. The decreasing rate varied among animals and was closely related to the time of abortion when P4 reached basal concentrations. In PLACE animals, gestation progressed normally and P4 did not change throughout the study (p > 0.05). None of the bitches presented side effects. It was concluded that acyline safely terminated mid-pregnancy by permanently decreasing P4 serum concentrations.  相似文献   
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对美国土壤侵蚀的历史及其后果的研究十分有意义。自美国殖民时期和 1 8世纪建国开始 ,有许多文献表明 ,最早期的殖民者已明了由于人们耕种土地产生的土壤侵蚀所引发的问题 ,也有意做点什么来减少土壤侵蚀。 1 86 1年各州之间发生战争 ,有记录表明 ,河流被来自管理不善的农田的泥沙淤塞。由于认为土地资源取之不尽 ,当时的农民常常是当农地变得无法耕种时 ,就打起行装向西部新的土地转移。然而很快当全国从东海岸到西海岸都居住有人后 ,这种做法就行不通了。2 0世纪 30年代的大平原“沙尘暴”及随之而来的美国经济大萧条 ,为罗斯福政府创造…  相似文献   
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AIMS: To investigate public attitudes towards barking dogs in New Zealand in order to quantify the extent to which people perceive barking dogs to be a problem, to compare tolerance of barking with that of other common suburban noises, to assess the level of public understanding about the function of barking, to determine risk factors for intolerance of barking and to assess knowledge of possible strategies for the investigation and management of problem barking.

METHODS: A 12-page questionnaire was sent to 2,000 people throughout New Zealand randomly selected from the electoral roll. Risk factors for being bothered by barking were examined using logistic regression analysis.

RESULTS: A total of 1,750 questionnaires were successfully delivered; of these, 727 (42%) were returned. Among respondents, 356/727 (49.0%) indicated that frequent barking during the day would bother them while 545/727 (75.0%) would be bothered by barking at night. Barking and howling were ranked above other suburban noises as a cause of annoyance. Risk factors for being bothered by daytime barking were not being home during the day, not owning a dog, and considering a dog bite to be a serious health risk. Risk factors for being bothered by night-time barking were not being home during the day, marital status, considering dog bites to pose a serious health risk, and having been frightened by a dog. Overall, 510/699 (73%) respondents understood that barking was a form of communication.

Action likely to be taken by 666 respondents hearing frequent barking included notifying and offering to help the owner (119; 17.8%), complaining to the owner (127; 19.1%) or the authorities (121; 18.2%), or doing nothing (299; 48%). Possible responses by 211 dog owners if they had a barking dog included seeking help from dog trainers (59; 28%) or behaviourists (54; 26%), buying an anti-barking device (33; 15%) or getting rid of the dog (20; 10%).

CONCLUSIONS: Barking was considered to be potentially disturbing by respondents to this survey. Attitudes towards barking were most influenced by age, dog ownership, past experience with dogs and attitude towards dog bites. Public understanding of the possible reasons for barking and appropriate methods of managing the behaviour when it becomes a problem could be improved by better education and the provision of information through veterinary clinics and social media.  相似文献   
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