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1.
Eggs of European hake (Merluccius merluccius L.) were stripped from fish caught at sea. Larvae were kept under semi‐intensive conditions at around 12°C. In addition, eggs were incubated in single wells at 9.2, 12.7 and 14.5°C, where hatching, development and survival were closely examined. During the larval stage, a total of 299 larvae were sampled to follow development and growth. In addition a small number of juveniles were sampled. Larvae hatched approximately 4 days after fertilization, and were 2.9 mm in total length (TL). At 6‐day post hatching (dph), the larvae were 4.1 mm (TL), the jaw apparatus was developed, and the larvae had started to feed. Most of the growth during the early larval period is restricted to the head, and there is almost no increase in length for the first 3–4 weeks post hatching. Teeth and pelvic fins appear at 25 dph. Development of unpaired fins at approximately 30 dph marks the start of the larval–juvenile transition. Weaning to formulated feed was accomplished 50 dph, when external morphology was similar to that of adult hake.  相似文献   
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OBJECTIVE: To examine to what extent the obesity epidemic is a general phenomenon in adults by assessing the secular change, by birth cohort and age, in the prevalence of obesity and median body mass index (BMI) in Danish men and women measured between 1964 and 1994. DESIGN: Multiple cross-sectional population surveys. SETTING: The greater Copenhagen area of Denmark. SUBJECTS: The study included 17,065 men (30 336 observations) and 13,417 women (24,065 observations), aged 20-84 years. MAIN OUTCOME MEASURES: Trends in median BMI and prevalence of obesity estimated from measured height and weight in 10-year age groups. RESULTS: In general the prevalence of obesity was increasing, although in an irregular way: among men in two phases, during the 1970s and 1990s and among women only during the 1990s. Great heterogeneity was observed between birth cohorts and age groups. There was only little indication of an increasing trend in obesity prevalence for women, except for the 55-64-year-olds. In men, the prevalence of obesity was increasing in all age groups except in the youngest ones, and it was statistically significant only for men aged 35-74 years. There was no significant linear change in median BMI in any group, except for an increasing trend among men aged 50 years and above. CONCLUSION: Although the overall Danish trend for obesity prevalence, similar to trends world-wide, showed a marked increase, the trend was very heterogeneous and generally neither uniform nor significantly positive; the changes were irregular, different among men and women, and different in the different age and birth cohorts. The obesity problem in middle-aged and older men of certain birth cohorts poses a specific public health challenge. Future studies of determinants behind the heterogeneity in the development of the obesity epidemic may provide clues to its causes.  相似文献   
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The International Cooperative Programme on Assessment and Monitoring of Acidification of Rivers and Lakes (ICP Waters) was established in July 1985 under the United Nations Economic Commission for Europe (UN/ECE) Executive Body of the Convention on Long-Range Transboundary Air Pollution (LRTAP). The Programme Centre is at the Norwegian Institute for Water Research, Oslo. The main aim of the Programme is to assess, on a regional basis, the degree and geographical extent of acidification of surface waters. 23 countries in Europe and North America participate on a regular basis. The major findings in the programme cover (1) regional trends in water chemistry related to changes in S- and N-deposition, (2) dose/response relationships particularly between biology (invertebrates) and water chemistry (acidification status), (3) effects of acidification on aquatic fauna, (4) implications for the assessment of critical loads, and (5) nitrogen leaching. Both chemical and biological intercalibrations and intercomparisons are important parts of the programme activities.  相似文献   
4.
The main lesions of paratuberculosis in ruminants are in the small intestine. Previous studies have shown that the bacterium enters the small intestine through M cells found in the follicle-associated epithelium lining the domes of the Peyer's patches. The everted sleeve method, devised for the in vitro study of intestinal absorption, was used in this study to investigate the uptake of Mycobacterium avium subsp. paratuberculosis in goat intestine. Everted small intestinal sleeves of goat kids, prepared from areas with and without Peyer's patches, were incubated for 60 min in 3H-labeled bacterial solution. The results of this study imply that the bacteria can enter the intestinal mucosa of the jejunum, both in areas with and without Peyer's patches. These findings indicate, therefore, that M. avium subsp. paratuberculosis bacteria not only enter through M cells but also through enterocytes.  相似文献   
5.
Berlin A  Djurle A  Samils B  Yuen J 《Phytopathology》2012,102(10):1006-1012
Puccinia graminis, the causal agent of stem rust, was collected from its alternate host barberry (Berberis spp.) and two different uredinial hosts, oats (Avena sativa) and rye (Secale cereale). The samples were analyzed using 11 polymorphic simple sequence repeat (SSR) markers. There were large differences between fungal populations on oats (P. graminis f. sp. avenae) and rye (P. graminis f. sp. secalis), and the genetic variation within the different formae speciales was also high. It was possible to distinguish between the two formae speciales on barberry. Additional genotypic groups not present in the field samples from oats and rye were also identified on barberry. Our results confirm the importance of barberry in maintaining the populations of P. graminis in Sweden and the importance of the sexual stage for the survival of the pathogen.  相似文献   
6.
A novel insertion element belonging to the IS110 family was identified in Mycobacterium avium subsp. paratuberculosis. The IS element, ISMpa1, is 1500 bp and has one ORF encoding a putative transposase. Three copies of ISMpa1 were identified in the M. avium subsp. paratuberculosis genome. The element had inserted into the 3' end of the highly conserved mycobacterial genes prrB and a homologue of M. tuberculosis Rv1593c, and between a putative cytochrome p450 oxygenase and a putative hydrolase. The IS element was present in all (n = 11) M. avium subsp. paratuberculosis strains but not detected in most other mycobacterial species examined, including 10 M. avium subsp. avium isolates of human, avian and porcine origin. However two porcine isolates of M. avium subsp. avium and the reference strain IWGMT49 did harbour ISMpa1. These three strains belong to a previously described subgroup of M. avium subsp. avium based on IS1245 restriction fragment length polymorphism (RFLP) pattern and serovars. All of the M. avium subsp. paratuberculosis strains examined had an identical RFLP pattern when probed with sequences corresponding to the 5' end of ISMpa1, whereas a different pattern was seen in the positive M. avium subsp. avium strains. This novel IS element might be a useful tool in strain classification of M. avium subsp. avium and also for the identification of M. avium subsp. paratuberculosis when used in combination with IS900.  相似文献   
7.
The red fox (Vulpes vulpes) can be considered as a relevant indicator species for Salmonella in the local environment and Salmonella faecal carriage was investigated in 215 red foxes in Norway shot during the winters 2002/2003 and 2003/2004. Fourteen (6.5%) of the foxes carried Salmonella. Four isolates were determined as serovars Kottbus (n=2) and Hessarek (n=2) of Salmonella enterica subspecies enterica, and one as S. enterica subspecies IIIb:61:k:1,5,(7). The remaining nine isolates were S. enterica subspecies enterica serovar Typhimurium 4,12:i:1,2 and all displayed the same pulsed-field gel electrophoresis (PFGE) profile designated A2. This serovar regularly causes disease outbreaks amongst small passerine birds during winter and most of these outbreaks are associated with the PFGE profile A2. The results strongly indicated that the Salmonella Typhimurium infections in red foxes were primarily acquired through ingestion of infected small passerines. To investigate the capability of the A2 strain to establish a true intestinal infection in the fox an inoculation experiment with an A2 isolate from small passerines was carried out in farmed silver foxes (V. vulpes). The experiment also included one strain with an uncommonly occurring profile (X201) from small passerines. To highlight possible differences in capability of the two inoculation strains to pass the acid gastric juice in the fox, in vitro studies of their acid tolerance was carried out. Also their catalase activity and biofilm production were studied. All three foxes inoculated with the A2 strain developed sub-clinical intestinal infection of 2 weeks duration, whereas none of the three foxes inoculated with the X201 strain shed this bacterium. The X201 strain displayed a much lower capability, than the A2 strain, to survive at pH 3 in vitro. The low acid tolerance probably made it difficult for the X201 strain to pass the stomach and establish an intestinal infection in the experimental foxes. Reduced catalase activity and biofilm production were found for the X201 strain, indicating that the low acid tolerance was caused by a defect in the stationary-phase stress response system.  相似文献   
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To date, the public health relevance of mycobacterial infections in pigs is not well investigated despite high risk of infection. Recently, there has been a documented increase in opportunistic infections and risk of acquiring opportunistic mycobacterial infections in HIV/AIDS patients in Mubende district; unfortunately, there has been no published information on the epidemiology of mycobacterial infections in this area. This study was carried out between September 2008 and February 2009. Investigations were done to assess the prevalence and associated risk factors of mycobacterial infections in slaughtered pigs in Mubende district of Uganda. A total of 997 pigs (53.7% male and 46.3% female) from 31 different slaughterhouses were examined for the presence of lesions compatible with TB and mycobacterial infections. Pathologic tissue specimens were collected for culturing and isolation of mycobacteria. A cross-sectional technique was used based on convenient visits to slaughterhouses but random selection of individual slaughtered pigs for a detailed post-mortem inspection on a daily basis. The results reflected a 9.3% and 3.1% (95% CI) prevalence of Mycobacterium species based on necropsy examinations and culture isolation, respectively. The highest prevalence of mycobacterial infection was recorded in Buwekula County (the mixed agro-zone) whilst the lowest was in Kassanda County (pastoral zone). A multivariable logistical regression analysis identified age (P ≤ 0.001) and sex (P ≤ 0.05) as risk factors for mycobacterial infections in pigs. Post-estimation statistics of the regression model evaluation and validation fit it well into the data (HL, χ 2 = 5.9; P = 0.69 for necropsy, HL χ 2 = 2.9; P = 0.94 for culturing). This study documented a high prevalence of mycobacterial infections in slaughter pigs in Mubende district. The fact that pigs and human often share common housing and environment poses a high risk of zoonotic transmission. This then warrants further molecular investigation to identify the specific Mycobacterium species and their public health importance in this area.  相似文献   
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