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991.
S Stagno D W Reynolds E S Huang S D Thames R J Smith C A Alford 《The New England journal of medicine》1977,296(22):1254-1258
The overall prevalence of congenital cytomegalovirus infection among the offspring of a highly immune young female population was 2.4 per cent (23 of 939). To ascertain whether the presence of anticytomegalovirus antibodies protects the developing fetus, we examined the offspring of 239 prospectively studied women. Despite substantial levels of preconceptional antibodies, intrauterine cytomegalovirus infection occured in seven of 208 (3.4 per cent) seroimmune women. Three neonates with congenital infection were born to 31 initially seronegative women. All the congenitally infected infants had subclinical involvement. Maternal humoral immunity may not protect the fetus against congenital cytomegalovirus infection. Neutralization kinetics and restriction enzyme analysis with endonucleases (EcoR-1 and HinD 111) demonstrated antigenic and genetic homology between viral strains isolated from two siblings consecutively infected in utero, indicating that repeat maternal infection with the same virus is transmissible to sequential products of conception. 相似文献
992.
Addressing the need for updated teaching hospital facilities is one of the most significant issues that an academic medical center faces. The authors describe the process they underwent in deciding to build a new facility at the Medical University of South Carolina (MUSC). Initial issues included whether or not the teaching hospital would continue to play a role in clinical education and whether to replace or renovate the existing facility. Once the decision to build was reached, MUSC had to choose between an on-campus or distant site for the new hospital and determine what the function of the old hospital would be. The authors examine these questions and discuss the factors involved in different stages of decision making, in order to provide the academic medicine community guidance in negotiating similar situations. Open communication within MUSC and with the greater community was a key component of the success of the enterprise to date. The authors argue that decisions concerning site, size, and focus of the hospital must be made by developing university-wide and community consensus among many different constituencies. The most important elements in the success at MUSC were having unified leadership, incorporating constituent input, engaging an external consultant, remaining unfazed by unanticipated challenges, and adhering to a realistic, aggressive timetable. The authors share their strategies for identifying and successfully managing these complex and potentially divisive aspects of building a new teaching hospital. 相似文献
993.
Evan D. Nair-Gill Chengyi J. Shu Caius G. Radu Owen N. Witte 《Immunological reviews》2008,221(1):214-228
Summary: Non-invasive monitoring of adaptive immunity in infection, cancer, and autoimmunity remains a major challenge. Current techniques to monitor lymphocytes involve numeric and functional determinations of immune cells isolated from the peripheral blood (most often) and tissue (rarely). Invasive measurements are prone to sampling errors and are poorly reflective of the dynamic changes in the location, number, and movement of lymphoid cells. These limitations indicate the need for non-invasive whole-body imaging methodologies that allow longitudinal, quantitative, and functional analyses of the immune system in vivo . Positron emission tomography (PET), a clinically based whole-body imaging modality, has the potential to revolutionize diagnostics and therapeutic monitoring in both clinical and pre-clinical settings. This review discusses studies using PET to image adaptive immune responses in small animal models. We address the challenges inherent in assessing whole-body immunity with PET and recent developments that can improve its performance. Finally, we discuss work to translate PET immune imaging into clinical practice. 相似文献
994.
Monhegan is an isolated 237-ha island lying 16 km off the coast of Maine. Introduced to the island in 1955, white-tailed deer, Odocoileus virginianus Zimmerman, reached a density of approximately 37/km2 by the mid-1990s. Black-legged ticks, Ixodes scapularis Say, first noticed in the late 1980s, flourished thereafter. Norway rats (Rattus norvegicus Berkenhout) on Monhegan are highly infected with Borrelia burgdorferi Johnson, Schmidt, Hyde, Steigerwalt, and Brenner, the agent of Lyme disease. By 1996, 13% of year-round residents had contracted the disease. The community's subsequent decision to eliminate deer from the island provided a unique opportunity to monitor the abundance of vector ticks in response to the complete and permanent removal of the primary hosts of their reproductive stage. With the exception of humans and their dogs and cats, there are no other potential hosts for adult I. scapularis on Monhegan. From November 1996 to March 1999, all deer were removed from the island. Previous annual fall flagging of vegetation from 1990 to 1998 produced 6-17 adult ticks/h, of which 24-41% were infected with the Lyme disease spirochete. During this same period, up to 18 larvae and 4 nymphs were removed per Norway rat live-trapped on the island each July. With the absence of deer in the fall of 1999, both the density of host-seeking adult ticks and infection prevalence rose substantially to 28/h and 75.0%, respectively. By the summer of 2003, however, no sub-adult ticks were found on rats, and that fall, only 0.67 adult ticks/h were flagged. Of the 68 adults collected from 2002 to 2003, 20 (29.4%) were infected. Over this same period, adult tick abundance on a deer-populated, reference island continued to gradually increase. 相似文献
995.
We have identified a new HLA-B*15 allele (B*1569) by polymerase chain reaction (PCR) using sequence-specific primers (SSP) and sequence-based typing (SBT). This novel allele was found in a 67-year-old white Caucasian male and differs from HLA-B*1503 at 3 positions. The nucleotide substitutions at positions 544, 559 and 560 result in amino acid changes at codon 158 from GCC (alanine) to ACC (threonine), and at codon 163 from CTG (leucine) to ACG (threonine). 相似文献
996.
L Binder D Smith T Kupka B Nelson B Glass M Wainscott J Haynes 《Archives of pathology & laboratory medicine》1989,113(1):73-76
A prospective observational study of 229 cases was conducted in a busy ambulatory care setting to evaluate the sensitivity, specificity, predictive values, and accuracy of spot urine urobilinogen and urine bilirubin assays as screening tests for serum liver function test (LFT) abnormalities. Both urine tests exhibited remarkably similar characteristics overall once they were adjusted to maximize accuracy and predictive values (occurring at a normal or abnormal "threshold," respectively, of 3.4 or 5.07 mumol/d for urobilinogen and 0 or 1+ for urine bilirubin). The percentage of cases correctly identified were 81% to 83% for serum bilirubin assays, 68% to 72% for other LFTs, but only 62% to 63% for screens for cases with at least one abnormal LFT finding. Poor sensitivities (47% to 49%) limited the detection of abnormal findings by the screen; both screens were reasonably specific (79% to 89%), but negative predictive values were suitable (89%) for serum bilirubin results only and were prohibitively lower (49% to 50%) in predicting all patients without LFT abnormalities. We conclude that spot urine urobilinogen and urine bilirubin determinations, although good screens for isolated serum bilirubin elevations, have unacceptable statistical properties as predictors of other LFT results due to a high proportion of false-negative results. 相似文献
997.
Azza M. A. Ibrahim A. A. Ragab M. A. Morsy M. M. Hewedi C. J. Smith 《Food and Agricultural Immunology》1994,6(1):39-44
This paper details the results obtained when a number of egg samples, collected in Egypt from different races of chicken were analyzed for the presence of the organochlorine insecticides aldrin and dieldrin. A simple ELISA was used for the detection and quantification of aldrin and dieldrin. The test was modified for application in this high protein system. Pesticide was detected in 83–352% (14/17) of the samples at levels ranging from 0.006 to 0.7 ppm (0.006 to 0.7 μg ml‐1). People eating eggs containing these amounts of pesticides which are above the World Health Organisation average daily intake levels would be at increased risk. 相似文献
998.
The diffusion of fixatives is slow. Early work using plasma gels and animal tissues showed the distance penetrated by a fixative to be a simple function of the fixation time but this relation has not been established in human tissues. The rates of diffusion into whole human spleens were measured for three primary fixatives over periods ranging from one to 25 days. A positive correlation was demonstrated between penetration distance (mm) and fixation time (hours). The diffusion rates were slower than those in previous studies. These results have possible implications for the handling of surgical specimens. 相似文献
999.
Growth of diploid cells from breast cancers 总被引:1,自引:0,他引:1
Cell cultures were derived from normal and cancerous breast tissues and from metastases by methods that selected for relatively adherent epithelial aggregates. Karyotypic analyses of first or second passage cultures yielded predominantly normal diploid cells. Nonclonal aberrations were more common in tumor-derived than in normal cultures. Three of the cultures that originated from metastases were characterized by abnormal clones. These results support observations based on DNA content, which indicate that a considerable fraction of breast cancers are composed predominantly of diploid cells. They differ greatly from chromosomal findings in long-term cultures of tumor effusions and thus emphasize the karyotypic diversity that can be found in tumors from a single tissue of origin--the breast. 相似文献
1000.
Effect of histamine infusion on circulating methionine-enkephalin and catecholamine concentrations 总被引:1,自引:0,他引:1
In 5 normal adult men, histamine was infused i.v. for 5 min at 20 micrograms/kg/h and at 80 micrograms/kg/h on two occasions one week apart. Diastolic blood pressure fell and heart rate, plasma adrenaline and noradrenaline all rose in a dose-dependent manner, but plasma methionine-enkephalin (Met-Enk) concentrations were unchanged. These results indicate that while Met-Enk may be co-stored with catecholamines (CAs) in the adrenal medulla in at least this paradigm, circulating concentrations of CAs may be altered without similar changes in plasma Met-Enk immunoreactivity. 相似文献