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On the basis of clinical signs and histological findings eight 9-month-old male rusa deer ( Cervus timorensis ) were diagnosed with sheep associated-malignant catarrhal fever. Following a variable course involving rectal temperatures around 40.5°C, depression, inappetence, diarrhoea, corneal opacity and hypopyon all animals died or were euthanased over a 5-week period. Severe multifocal vasculitis, mainly periglomerular and in the arcuate vessels were consistent histological findings which in the past have been adequate to confirm clinical diagnosis of sheep associated-malignant catarrhal fever. A nested poly-merase chain reaction test has been used to detect a sheep associated-malignant catarrhal fever PRC product, 238 base-pairs in size, in DNA extracted from lymphocyte preparations. The result supported the diagnosis of sheep associated-malignant catarrhal fever in these deer.  相似文献   
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OBJECTIVE: To evaluate the long-term risks and benefits of early-age gonadectomy, compared with traditional-age gonadectomy, among cats adopted from a large animal shelter. DESIGN: Retrospective cohort study. ANIMALS: 1,660 cats. PROCEDURE: Cats underwent gonadectomy and were adopted from an animal shelter before 1 year of age; follow-up was available for as long as 11 years after surgery (median follow-up time, 3.9 years). Adopters completed a questionnaire about their cats' behavior and medical history. When possible, the cats' veterinary records were reviewed. Statistical analyses were conducted to identify any associations between the occurrence of 47 medical and behavioral conditions and the cats' age at gonadectomy. RESULTS: Among male cats that underwent early-age gonadectomy (< 5.5 months of age), the occurrence of abscesses, aggression toward veterinarians, sexual behaviors, and urine spraying was decreased, whereas hiding was increased, compared with cats that underwent gonadectomy at an older age. Among male and female cats that underwent early-age gonadectomy, asthma, gingivitis, and hyperactivity were decreased, whereas shyness was increased. CONCLUSIONS AND CLINICAL RELEVANCE: Gonadectomy before 5.5 months of age was not associated with increased rates of death or relinquishment or occurrence of any serious medical or behavioral condition and may provide certain important long-term benefits, especially for male cats. Animal shelters can safely gonadectomize cats at a young age, and veterinarians should consider recommending routine gonadectomy for client-owned cats before the traditional age of 6 to 8 months.  相似文献   
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Abstract Recreational fisheries statistics can provide valuable information on the dynamics of fish stocks and their exploitation. For some reservoirs in the Czech Republic, there are conspicuous synchronous fluctuations in catches of different species that might be caused by fishing skills and strategies. This study describes a method that could detect signatures of such phenomena in individual logbooks. It classifies anglers by species reported during 1 year and compares the resulting angler groups by group size, fishing effort, catch per unit effort (CPUE) and annual catch. The method is illustrated by data from one reservoir, showing that the number of generalist anglers who caught several species was higher than expected. Generalists also had higher catches and effort but lower CPUE than specialists who caught only one of the species. The results indicate that generalist anglers with a low degree of specialisation and high effort could contribute to long‐term correlations in species catches.  相似文献   
47.
Interactions of fire cycle and plant species' reproductive characteristics could determine vegetation distribution pattern of a landscape. In Canada's boreal region, fire cycles before the Little Ice Age (c. 1850s) ranged from 30-130 years and 25-234 years afterwards until the settlement period (c. 1930s) when longer fire cycles occurred in response to climatic change and human interference. Analysis indi-cated that fire cycles were correlated with growing season (April-October) temperature and precipitation departure from the 1961-1990 nor-mal, varying by regions. Assuming that wildfires will respond to future warming similar to the manner during the past century, an assess-ment using climatic change scenarios CGCM1, CGCM2 and HadCM2 indicates fire cycles would divert to a range of 80-140 years in the west taiga shield, more than 700 years for the east boreal shield and east taiga shield, and 300-400 years for the boreal plains in 2050.  相似文献   
48.
The persistence of foot-and-mouth disease virus on wool   总被引:1,自引:0,他引:1  
SUMMARY Five Suffolk sheep, held in a high-security isolation room, were exposed for 2 hours to the aerosol of 3 mature pigs that had been infected with foot-and-mouth disease virus (FMDV), strain O1-BFS. The fleeces of 3 of the sheep were contaminated with FMDV at 2 days post exposure (dpe), while at 5 dpe the fleeces of all 5 sheep were more extensively, and more heavily, contaminated. The persistence of FMDV on contaminated wool was examined in vitro using multiple 0.5 g samples of Merino wool that were each contaminated with one of 3 strains of FMDV in tissue-culture medium: O1-BFS, O-Morocco (O-MOR 9/91) or an Asia 1 strain (TAI 1/90). Wool samples were held at either 4°C, 18°C or 37°C, and decay curves were established for each virus at each temperature. These curves predicted that O1-BFS, O-MOR 9/91 and TAI 1/90 would fall below detect-able levels at 72, 70 and 48 days post contamination (pc), respectively, for wool stored at 4°C; at 11, 12 and 12 days pc, respectively, for wool stored at 18°C; and at 57, 68 and 33 hours pc, respectively, for wool stored at 37°C. For wool contaminated with O1-BFS-infected sheep faeces, urine or blood, or with O1-BFS-infected cattle saliva, decay curves predicted virus to persist for 5 to 11 days pc at 18°C. We demonstrated that the simulated scouring of FMDV-contaminated wool at 60° to 70°C would usually reduce virus to below detectable levels. The detergent component of the scouring process had little, if any, antiviral activity, and scouring at 20°C or 50°C had limited impact on FMDV titres . We recommend that either (1) simple storage of FMDV-contaminated wool for 4 weeks at temperatures of 18°C or higher, or (2) scouring of contaminated wool at 60° to 70°C would be sufficient to remove the threat of FMDV-contaminated wool being infectious to other animals .  相似文献   
49.
In the laboratory situation the preferences of dogs and cats for food seem to be relatively uniform. Cats prefer fish and commercial cat food to rats. Dogs prefer beef, pork and lamb to chicken, liver and horsemeat and strongly prefer meat to cereal diets. They prefer canned meat to fresh meat, ground meat to cubed meat and cooked meat to raw meat. Canned or semimoist preparations are preferred to dry ones. Pet dogs have much more variable preferences according to their owner's subjective evaluation. A variety of factors seem to be related in an as yet unknown way to some flavor preferences of pet dogs, i.e. the dog's sex/reproductive status, weight and relationship to owners and the content of the dog's meals. The complicated interaction between (a) a pet's taste, texture and olfactory sensation, (b) its owner's perception of the pet and its preferences and (c) its physical and social environment deserves further investigation.

Obesity can result from endocrinological causes such as those following ovariohysterectomy, but most cases appear to be related to owner-induced variables. In a kennel situation most, but not all, dogs can be allowed free access to palatable food without becoming obese.

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50.
The influence of hereditary and environmental factors is indispensable as the foundation on which the temperament of an animal is formed. Genetic research on animal temperament has experienced a turning point in recent years as a result of the development of molecular biology. In the near future, it may be possible to explain the formation process of animal temperament as the two fields share their research. We look forward to applying these research results to the development of new genetic treatment methods for problem behavior and training programs suited to the individual.  相似文献   
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