154 research outputs found
The Chemtrak Hp Chek Fingerstick Whole Blood Serology Test for the Detection of Helicobacter pylori Infection
To evaluate a new whole blood serology test (Hp Chek; ChemTrak) that detects IgG antibodies to Helicobacter pylori . Methods : The study was conducted at 10 sites within the United States. Patients undergoing upper endoscopy for dyspepsia were recruited for enrollment. Those treated for H. pylori infection within a year of endoscopy and those who had regularly used proton pump inhibitors, bismuth compounds, or antibiotics within a month of endoscopy were not eligible. During endoscopy, specimens were obtained from the corpus and antrum for histological examination, which was performed by a single experienced pathologist. The Hp Chek was tested using whole blood and serum. Serum was also tested with a reference enzyme-linked immunosorbent assay (ELISA) at a centralized location. Test characteristics for the Hp Chek and ELISA were calculated using histology as the “gold standard.”. Results : Two hundred eighty-seven patients (140 women and 147 men; mean age 53 ± 6 yr ) were enrolled. The Hp Chek was easy to perform and yielded results 9 min after inoculation of the test cassette with whole blood or serum. When the Hp Chek used with whole blood was compared with histology as the gold standard, the sensitivity was 88%, specificity 85%, positive predictive value 83%, negative predictive value 90%, and percent agreement 86%. There were no statistically significant differences among the results obtained with the Hp Chek using whole blood, the Hp Chek using serum, or reference ELISA. Conclusions : The Hp Chek whole blood serology test was easy to perform and rapid and yielded performance characteristics comparable to those of a reference ELISA or the Hp Chek used with serum.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75251/1/j.1572-0241.1998.016_c.x.pd
Nuclear matter at high density: Phase transitions, multiquark states, and supernova outbursts
Phase transition from hadronic matter to quark-gluon matter is discussed for
various regimes of temperature and baryon number density. For small and medium
densities, the phase transition is accurately described in the framework of the
Field Correlation Method, whereas at high density predictions are less certain
and leave room for the phenomenological models. We study formation of
multiquark states (MQS) at zero temperature and high density. Relevant MQS
components of the nuclear matter can be described using a previously developed
formalism of the quark compound bags (QCB).
Partial-wave analysis of nucleon-nucleon scattering indicates the existence
of 6QS which manifest themselves as poles of -matrix. In the framework of
the QCB model, we formulate a self-consistent system of coupled equations for
the nucleon and 6QS propagators in nuclear matter and the G-matrix. The
approach provides a link between high-density nuclear matter with the MQS
components and the cumulative effect observed in reactions on the nuclei, which
requires the admixture of MQS in the wave functions of nuclei kinematically.
6QS determine the natural scale of the density for a possible phase
transition into the MQS phase of nuclear matter. Such a phase transition can
lead to dynamic instability of newly born protoneutron stars and dramatically
affect the dynamics of supernovae. Numerical simulations show that the phase
transition may be a good remedy for the triggering supernova explosions in the
spherically symmetric supernova models. A specific signature of the phase
transition is an additional neutrino peak in the neutrino light curve. For a
Galactic core-collapse supernova, such a peak could be resolved by the present
neutrino detectors. The possibility of extracting the parameters of the phase
of transition from observation of the neutrino signal is discussed also.Comment: 57 pages, 22 figures, 7 tables; RevTeX 4; submitted to Phys. Atom.
Nuc
A New Eusuchian Crocodyliform with Novel Cranial Integument and Its Significance for the Origin and Evolution of Crocodylia
Crocodyliforms were one of the most successful groups of Mesozoic tetrapods, radiating into terrestrial, semiaquatic and marine environments, while occupying numerous trophic niches, including carnivorous, insectivorous, herbivorous, and piscivorous species. Among these taxa were the enigmatic, poorly represented flat-headed crocodyliforms from the late Cretaceous of northern Africa. Here we report a new, giant crocodyliform from the early Late Cretaceous (Cenomanian) Kem Kem Formation of Morocco. Represented by a partial braincase, the taxon has an extremely long, flat skull with large jaw and craniocervical muscles. The skull roof is ridged and ornamented with a broad, rough boss surrounded by significant vascular impressions, likely forming an integumentary structure unique among crocodyliforms. Size estimates using endocranial volume indicate the specimen was very large. The taxon possesses robust laterosphenoids with laterally oriented capitate processes and isolated epipterygoids, features allying it with derived eusuchians. Phylogenetic analysis finds the taxon to be a derived eusuchian and sister taxon to Aegyptosuchus, a poorly understood, early Late Cretaceous taxon from the Bahariya formation. This clade forms the sister clade of crown-group Crocodylia, making these taxa the earliest eusuchian crocodyliforms known from Africa. These results shift phylogenetic and biogeographical hypotheses on the origin of modern crocodylians towards the circum-Tethyean region and provide important new data on eusuchian morphology and evolution
Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine
[This corrects the article DOI: 10.1186/s13054-016-1208-6.]
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