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981.
OBJECTIVE: To determine the distribution and prevalence of sarcoptic mange in wombats, particularly the common wombat (Vombatus ursinus). DESIGN: Questionnaire survey in two parts. PROCEDURE: Questionnaires were distributed to biologists, rangers, animal carers and naturalists. Part 1 of the questionnaire aimed to determine the present distribution of sarcoptic mange in wombats (103 responses). Part 2 invited respondents to assess the prevalence of sarcoptic mange in wombats over a 3 month period (four responses). Information on wombats from 66 localities was received. Each locality represented an area of about 2500 km2. RESULTS: Mange was observed at 93% of localities surveyed and Sarcoptes scabiei was present in common wombats at 52% of localities. Sarcoptic mange was highly prevalent (22%) in two common wombat populations in Victoria. Anecdotal evidence suggested that mange epizootics are sporadic, cause significant morbidity and mortality and have a substantial effect on local abundance. The respondents did not report sarcoptic mange in either northern hairy-nosed wombats (Lasiorhinus krefftii) or southern hairy-nosed wombats (Lasiorhinus latifrons). CONCLUSIONS: Sarcoptic mange occurs in common wombat populations throughout the range of the common wombat including Tasmania and Flinders Island. While mange epizootics are sporadic, they have the potential to threaten the long-term survival of small, remnant populations. 相似文献
982.
ML Santiago EG Santiago JC Hafalla MA Manalo L Orantia MN Cajimat C Martin C Cuaresma CE Dominguez ME Borromeo AS De Groot TP Flanigan CC Carpenter KH Mayer BL Ramirez 《Canadian Metallurgical Quarterly》1998,18(3):260-269
OBJECTIVES: to identify the risk factors for hepatitis B (HBV) and hepatitis C (HCV) virus infections in drug users attending two drug treatment centres in Northwest England, and to evaluate the effect of both needle exchange and hepatitis B vaccination on the prevalence of hepatitis B and hepatitis C infections. METHODS: a retrospective, cross-sectional study performed at the Regional Infectious Disease Unit and a Primary Care Centre for drug users in Liverpool. The study population included 773 drug users who had hepatitis serology performed between January 1992 and April 1996. Information on risk factors was obtained from clinical records; hepatitis serology data were obtained from the Liverpool Public Health Laboratory database. RESULTS: the overall seroprevalences of exposure markers for HBV (anti-HBc antibody) and HCV (anti-HCV antibody) were 48% and 67%, respectively. Duration of injecting drug use was the strongest predictor of HCV infection, with a crude odds ratio of 8.9 (95% confidence interval (CI): 4.5-17) for >10 compared to <3 years of injecting, and was also a strong predictor of HBV infection, with an adjusted odds ratio (controlled for the effects of HBV vaccination) of 5.7 (95% CI: 3.2-10) for >10 compared to <3 years' injecting. Vaccination against HBV was associated with greatly reduced HBV seroprevalence (crude odds ratio 0.11, 95% CI: 0.06-0.18). Overall, HCV was acquired earlier in the injecting career than HBV, but drug users who were not vaccinated against HBV acquired markers for HBV even more rapidly than for HCV. We found no independent protective effect for either anti-HBc or anti-HCV acquisition after the introduction of a needle-exchange scheme. CONCLUSIONS: hepatitis C is highly prevalent among Merseyside drug users and is likely to prove difficult to control because of rapid acquisition early in the injecting career. Vaccination against hepatitis B is the best means of protecting drug users from hepatitis B, and should be offered before injecting is commenced. 相似文献
983.
Low concentrations of antibodies, specific to human respiratory syncytial virus (RSV) have been shown to enhance virus replication in human monocytic cell lines by several workers. In the present study, replication of bovine RSV in ovine peripheral blood monocytes was shown to be enhanced in the presence of low concentration of bovine RSV-specific antibodies. Antibodies had no enhancing effect on virus replication in secondary lamb testis cells or monocytic cell lines derived from peripheral blood monocytes. The possible effects of low titres of bovine RSV-specific antibodies on the development of clinical disease were examined by inoculating groups of lambs with a mixture of virus and antibodies and assessing the severity of clinical disease and by measuring venous oxygen (PO2) and carbon dioxide (PCO2) tensions, as hypoxia has been associated with respiratory diseases. Inoculation of bovine RSV and virus-specific antibody complexes to lambs did not enhance clinical disease and had no effect on the clinical chemistry, haematology and PO2 and PCO2 tensions. Groups of lambs inoculated with virus alone or virus-antibody complexes developed significant humoral and cellular immune responses. There was no significant difference in the cellular immune responses of lambs exposed to virus alone and lambs exposed to virus-antibody mixture, as measured by virus-specific lymphocyte transformation or by cytotoxicity assays but the period of virus shedding was longer in lambs inoculated with a mixture of virus and immune serum. 相似文献
984.
Aghina Maurí cio Alves C. M l Ant nio Carlos A. Jorge Carlos Alexandre F. Pereira Cl udio M.N.A. Varela Thiago F.B. Cunha Gerson G. Landau Luiz 《Computer Graphics and Applications, IEEE》2008,28(4):6-9
Current nuclear power plant simulators employ interfaces that use multiple computer displays to represent a simplified control desk. To make the simulation more realistic and effective, a proposed approach replaces the displays with a virtual control desk that precisely mimics the original. 相似文献
985.
G Meulemans S Roels TP van den Berg J Godfroid M Decaesstecker 《Canadian Metallurgical Quarterly》1998,143(11):300-303
A non-virulent Newcastle disease virus (strain APMV-1 96/89 VB) was isolated from a broiler chicken from a backyard flock. Using monoclonal antibodies, the virus was shown to be different from the vaccinal virus strains Hitchner, La Sota and Ulster. The virus was shown to replicate in the pancreas of one-day-old specific pathogen-free chickens infected orally, and the histological lesions observed in the pancreas of chickens inoculated with the fourth chicken passage of the virus five to nine days after infection were consistent with an acute pancreatitis. 相似文献
986.
TP Hitschold 《Canadian Metallurgical Quarterly》1998,179(2):540-543
OBJECTIVE: My purpose was to measure the volume of the fetoplacental vessel tree and to relate findings to Doppler flow patterns of the umbilical arteries. STUDY DESIGN: One hundred sixty placentas were examined by means of standardized random block placental histomorphometry after delivery and the results were compared with antenatal Doppler findings. RESULTS: There was a high correlation (r = -0.703) between the intravillous blood volume obtained from measurements of intermediate and terminal villi and the Doppler flow velocity waveforms detected within the last week before delivery. Moreover, the reduced size of a vessel tree less than 85 mL is highly predictive of perinatal complications, such as fetal growth restriction, low umbilical artery pH values after birth, reduced Apgar scores, and cesarean section for fetal distress. CONCLUSION: These data suggest that reduced end-diastolic flow velocities in the umbilical arteries are associated with elevated fetoplacental impedance owing to reduced vascularization of intermediate and terminal villi. 相似文献
987.
988.
ED Hsi TP Singleton SM Svoboda B Schnitzer CW Ross 《Canadian Metallurgical Quarterly》1998,110(3):327-333
To determine which genes may be activated or inactivated during breast cancer development, we employed two cloning strategies (subtractive hybridization and differential display) using RNA samples from a human breast tumor and its matching normal breast cell line. Of 950 clones isolated, 102 cDNA inserts were analysed by DNA sequencing and database searching. We found 30 clones that were obviously unidentified, with no significant homology to any listed human gene. We focused upon one of the novel genes, Di12, that is differentially expressed as a 1.35 kb RNA in breast cancer tissues and cell-lines, and in several normal tissues. A full length cDNA of this gene was cloned, and its DNA sequence revealed an open reading frame of 339 amino acids. Antibodies to the ten N-terminal amino acids were developed to investigate the expression of Di12 in breast cancer cell-lines and tumors. The Di12 protein was found in tissue sections of infiltrating ductal carcinomas (IDCs), but not in benign or normal breast specimens. RT-PCR analysis confirmed expression of Di12 in 80% of infiltrating ductal carcinomas (IDCs). As IDC constitutes approximately 70% of breast cancers seen clinically, the level of Di12 expression may be predictive of disease progression. 相似文献
989.
990.
Does restricted distribution limit access and coverage of yellow fever vaccine in the United States?
BACKGROUND: While human immunodeficiency virus (HIV)-related causes of death have been well documented in developed countries, in Africa data are scanty and mainly based on autopsy studies from city hospitals which are highly selective and may not represent causes of HIV-associated deaths in the general population. This study, from a rural population, describes the causes of death in HIV-positive people and their HIV-negative controls. METHODS: A natural history cohort comprising HIV-1 infected participants and HIV-negative controls was established in rural Uganda in 1990. Causes of death were determined by reviewing the premorbid clinical and laboratory findings and from information obtained from relatives. Blindness to the deceased's HIV serostatus was maintained throughout. RESULTS: In all, 78 deaths occurred over a 6-year period: 63 deaths occurred in the HIV-positive cases (53 prevalent and 10 incident cases) and 15 deaths in the HIV-negative controls. Of the prevalent cases, 56%, and 9% the incident cases enrolled died, compared with 7% of the HIV-negative controls. Of the 55 HIV-positive cases with sufficient data to establish cause of death, 52 (95%) were assessed as having HIV-associated deaths and 48 (87%) died in WHO stage 4 (AIDS). The main causes of death were wasting syndrome (31%), chronic diarrhoea (22%), cryptococcal meningitis (13%) and chest infection (11%). CONCLUSIONS: Our results represent an unbiased selection of deaths in a rural area. The HIV-positive cases have high death rates and die of HIV-related pathologies. The main causes of death reflect the WHO clinical case definition of AIDS. Cryptococcal meningitis is also a common cause of death in this population. 相似文献