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Four outbreaks of hemorrhagic septicemia caused by Pasteurella multocida multocida occurred in a population of 1,800 fallow deer (Dama dama) during 1992-1996. A total of 340 fallow deer were submitted for postmortem examination. Pasteurellosis was diagnosed in 273 of 312 deer suspected of having septicemia. Pasteurella multocida was isolated from 257 animals, and the diagnosis was based on typical pathologic changes alone in the other 16 animals. Pasteurella multocida was isolated in pure culture from 219 of 248 samples of cerebrospinal fluid. Eighteen animals were observed moribund with severe depression, foamy nasal discharge, and respiratory distress, and 257 were found dead. Major clinical signs and pathologic changes included extensive swelling of the head and the neck and peracute or acute septic pneumonia, petechial and ecchymotic hemorrhages on serous membranes, and severely hemorrhagic adrenal glands and abomasum. Rhinitis and necrotic pharyngeal mucosae were common. Histologically, the most advanced lesions were in the nasal mucosa and pharynx. The swelling of the head and the neck arose from a diffuse cellulitis in the subcutaneous and intermuscular tissues. The earliest lesions in the lungs included large numbers of bacteria in the pulmonary capillaries, but various degrees of fibrinous exudation to the alveoli and infiltration with heterophils usually were observed.  相似文献   
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Ascaris suum eggs were collected from pig faeces or dissected from worms obtained from the same pigs. Eggs from the two sources were allowed to embryonate in 0.1 N H2SO4, in 1% buffered formalin or in tap water. The embryonation of the sulphuric acid and water cultures occurred at the same speed, while the formalin cultures developed slightly more slowly. By experimental inoculation of helminth-free pigs and subsequent counting of white spots in the livers and larvae in the lungs day 7 p.i., the infectivity of eggs dissected from worm uteri and embryonated in sulphuric acid (a normal laboratory procedure) was compared with that of eggs collected from faeces and embryonated in water (i.e. more naturally developed eggs). The results suggest that the two types of eggs were equally infective. For this reason the common practice of using Ascaris eggs dissected from worms for experimental infections might be acceptable.  相似文献   
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Increasing demands for cost-effectiveness in surveillance for human health hazards from animal origins can be met by introducing risk-based principles. This e.g. implies targeting subpopulations with higher risk of infection compared to the whole population. Furthermore, historical data from surveillance can be collated and used to assess future risk of infection. To demonstrate the effectiveness of combining these two approaches, we used a model called “Discounting historical evidence”. It depends mainly on the annual risk of introduction (PIntro) and the surveillance system sensitivity (SSe) (ability to detect infection if present). The model implies simulations that reiterate for a number of years. For each year the output is updated with the confidence on absence in infection. Trichinella spiralis infection in pigs is used as an example. In Denmark, more than 20 million pigs are tested annually. Despite more than 70 years of testing no pigs have been found positive for Trichinella. Hence, PIntro is low. SSe can be estimated from the maximum number of infected carcasses expected under the specified design prevalence, and the sensitivity of the test applied. According to our assessment, the current prevalence of Trichinella in Danish pigs is less than one case per million, which we interpret as negligible risk. Based on this, a risk-based surveillance programme for Trichinella is designed that targets all out-door reared pigs as well as all sows and boars (current total 610,000 slaughtered annually). These subpopulations are judged to have higher risk of getting Trichinella. Again, SSe and PIntro are estimated and the model results show that risk-based surveillance can be applied without jeopardizing human health. Finally, we incorporate wildlife surveys and test quality assurance in the programme. The results of the simulation model were included in an application to the European Commission concerning Denmark's status as a region with negligible risk of Trichinella. In July 2007, the European Commission granted status as “negligible risk” to Danish pigs and pork.  相似文献   
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Evidence of estrogen receptors in normal human osteoblast-like cells   总被引:80,自引:0,他引:80  
In seven strains of cultured normal human osteoblast-like cells, a mean of 1615 molecules of tritium-labeled 17 beta-estradiol per cell nucleus could be bound to specific nuclear sites. The nuclear binding of the labeled steroid was temperature-dependent, steroid-specific, saturable, and cell type-specific. These are characteristics of biologically active estrogen receptors. Pretreatment with 10 nanomolar estradiol in vitro increased the specific nuclear binding of progesterone in four of six cell strains, indicating an induction of functional progesterone receptors. RNA blot analysis demonstrated the presence of messenger RNA for the human estrogen receptor. The data suggest that estrogen acts directly on human bone cells through a classical estrogen receptor-mediated mechanism.  相似文献   
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The prevalence of Coxiella burnetii and Chlamydia psittaci antibodies was investigated in 530 dog specimens divided into six groups, i. e. A = private watch dogs, B1 = service dogs from Bratislava, B2 = service dogs from other localities of Slovakia and Moravia, C = watch dogs from farms, I = household dogs, T = stray dogs. The dogs demonstrated the higher seropositivity to C. burnetii (11.7%) than to Ch. psittaci (5.5%). The highest percentage of antibodies to C. burnetii was found in stray dogs (23.7%), less prevalence of antibodies was observed in the animals in group C (13.6%), almost the same positivity was proved in the dogs of group B1 and B2 (10.5 and 10.6%). The highest positivity to Ch. psittaci was demonstrated in the dogs of group A (8.7%), less in group B2 (6.6%) and the least number in group B1 (1.9%). The stray dogs occupied the intermediate position in this data (Tab. I). Ninety four localities were tested, from which 38 were seropositive. Neither acute coxiellosis nor chlamydiosis were proved in any animals examined. Ninety per cent of dogs were found healthy, but 10% of dogs demonstrated hepatopathia and gastroenteritis. Two of them (category A and I) were seropositive to C. burnetii (titer 1:8 to 1:16) and one to Ch. psittaci (titer 1:16). Both C. burnetii and Ch. psittaci attack dogs parallely with the agents of other zoonoses, of which the most common is Toxoplasma gondii (Tab. II). Several dogs demonstrated seropositivity to three up to five zoonotic agents (Tab. III).  相似文献   
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Core LJ  Lis JT 《Science (New York, N.Y.)》2008,319(5871):1791-1792
Recent work has shown that the RNA polymerase II enzyme pauses at a promoter-proximal site of many genes in Drosophila and mammals. This rate-limiting step occurs after recruitment and initiation of RNA polymerase II at a gene promoter. This stage in early elongation appears to be an important and broadly used target of gene regulation.  相似文献   
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