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Projecting cancer risks from exposure to space radiation is highly uncertain because of the absence of data for humans and because of the limited radiobiology data available for estimating late effects from the high-energy and charge (HZE) ions present in the galactic cosmic rays (GCR). Cancer risk projections involve many biological and physical factors,(More)
The possibility and probability of natural transfer of viable microbes from Mars to Earth and Earth to Mars traveling in meteoroids during the first 0.5 Ga and the following 4 Ga are investigated, including: --radiation protection against the galactic cosmic ray nuclei and the solar rays, dose rates as a function of the meteorite's radial column mass(More)
To date, apoptosis has been characterized biochemically by the production of 180-200 bp internucleosomal DNA fragments resulting from the activation of an endonuclease(s). The principal morphological feature of apoptosis is the condensation of chromatin and it has been assumed that this may reflect the oligonucleosomal fragmentation pattern. We have(More)
Apoptosis is an active mechanism of cell death required for normal tissue homeostasis. Cells require survival signals to avoid the engagement of apoptosis. In the mammary gland, secretory epithelial cells are removed by apoptosis during involution. This cell loss coincides with matrix metalloproteinase activation and basement membrane degradation. In this(More)
Nocardia, a gram-positive bacillus with the microscopic appearance of branching hyphae, can produce considerable disease in the appropriate host. The taxonomy of Nocardia continues to evolve; more than 50 species have been described. Early recognition and effective therapy are imperative to achieve successful outcomes. Although nocardiosis typically occurs(More)
Three hard winter wheat varieties (Akron, Trego, and Platte) were examined and compared for their free radical scavenging properties and total phenolic contents (TPC). Free radical scavenging properties of wheat grain extracts were evaluated by spectrophotometric and electron spin resonance (ESR) spectrometry methods against stable(More)
A thickened bronchial epithelial basement membrane has long been regarded as a histopathologic characteristic of bronchial asthma. As we had previously demonstrated that this phenomenon is due to the deposition of interstitial collagens and fibronectin, we have now sought to determine the nature of the cell responsible for this process by studying(More)
The effects of volume of blood, number of consecutive cultures, and incubation time on pathogen recovery were evaluated for 37,568 blood cultures tested with the automated BACTEC 9240 instrument (Becton Dickinson Diagnostic Instrument Systems) at a tertiary care center over the period of 12 June 1996 through 12 October 1997. When the results for this study(More)
When shielding from cosmic heavy ions, one is faced with limited knowledge about the physical properties and biological responses of these radiations. Herein, the current status of space shielding technology and its impact on radiation health is discussed in terms of conventional protection practice and a test biological response model. The impact of(More)
Crews working on present-day jet aircraft are a large occupationally exposed group with a relatively high average effective dose from galactic cosmic radiation. Crews of future high-speed commercial aircraft flying at higher altitudes would be even more exposed. To help reduce the significant uncertainties in calculations of such exposures, the atmospheric(More)