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991.
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
992.
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
993.
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
994.
995.
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
996.
997.
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
998.
Healthy behaviors among women in the United States and Ontario: the effect on use of preventive care
OBJECTIVES: This study examined how several healthy behaviors among women in Ontario and the United States explained (1) the use of preventive health services, (2) differences in use between socioeconomic groups, and (3) differences in use between the two health systems. METHODS: 1990 data on women from the Ontario Health Survey (n = 22,985) and the US National Health Interview Survey (n = 19,092) were analyzed. A woman who avoided smoking and obesity, used seatbelts, and regularly engaged in aerobic exercise was defined as having a healthy lifestyle. Women were considered screened if they reported a mammogram or a breast exam within the previous year or a Pap smear within 2 years. RESULTS: A healthy lifestyle was more common in the United States than Canada among more highly educated groups (odds ratio [OR] = 1.40; 95% confidence interval [CI] = 1.22, 1.60 for college educated) but less common in the United States for those with less than a high school education (OR = 0.52; 95% CI = 0.40, 0.67). Each additional unhealthy behavior decreased the odds of having undergone a mammogram in the previous year by 20%. However, adjusting for the number of unhealthy behaviors did not substantially change the relationship between socioeconomic status and use of preventive services. CONCLUSIONS: The number of healthy behaviors is an important measure of demand for preventive health services. This measure varies across country and socioeconomic group. 相似文献
999.
1000.
A. K. Biswas Leikhram Kripriyalini S. Tandon Divya Sharma S. Majumder 《Food Analytical Methods》2016,9(10):2872-2879
The aim of this study was to develop a simple method for simultaneous identification of two different domains of calpains (μ- and m-calpains) in blood and turkey meat samples. The method is based on Tris-based extraction techniques followed by casein zymography detection. The extracts were purified by dialysis, and target compounds were separated on Diethylaminoethyl (DEAE)-Sephacel anion-exchange chromatography. Results indicated that a buffer pH of 6.7 produced optimum extraction efficiency. The separation of calpastatin, μ- and m-calpains on column chromatography was carried out using stepwise elution profiles of 100, 200, and 400 mM NaCl solutions, respectively. Casein zymography study clearly demonstrated the presence of μ- and m-calpains in the crude extracts of breast and blood samples; however, μ-calpain was absent in the thigh sample. Similarly, sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis identified both the calpains from muscle and blood samples, but presence of calpastatin was observed in both the breast and thigh muscle samples only. The activity analysis of purified fractions indicated that both the μ- and m-calpain concentrations were differed significantly (P?<?0.05) amongst breast, thigh and blood samples. Collectively, it was concluded that Tris buffer (pH 6.7) and DEAE-Sephacel column for extraction and separation of μ- and m-calpains and casein zymography and SDS-PAGE detection methods were most suitable for accurate identification of calpains and calpastatin from blood and turkey meat samples. 相似文献