Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Repositories”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,621 records · Page 90Linked to original sources
PubMed1995

Radon emanation coefficients for phosphogypsum.

Phosphogypsum is a by-product of the phosphate fertilizer industry which is stockpiled in large quantities world-wide. Phosphogypsum consists mainly of dihydrate gypsum (CaSO42H2O) but also contains elevated concentrations of 226Ra and other inorganic species which originate from the processing of phosphate rock. 222Rn gas is the first decay product of 226Ra and has been identified as one of the major environmental concerns associated with phosphogypsum. This study was conducted to determine effects of particle size, weathering, and moisture content on the 222Rn emanation coefficient (epsilon) for phosphogypsum. Average epsilon for air-dry, unfractionated phosphogypsums derived from Togo, Florida, or Idaho rock was approximately 12%. Average epsilon for fine fraction phosphogypsum (< 20 microns diameter) was greater than for unfractionated phosphogypsum by a factor of 4.6, 1.4, and 4.4 for samples derived from Idaho rock, Togo rock, and Florida rock, respectively. Phosphogypsum samples subjected to an artificial weathering procedure lost 40% mass, with no change in epsilon. Increasing water content was found to first slightly decrease, then to increase epsilon compared to air-dry samples; epsilon for 100% saturated phosphogypsum was 1.9-fold greater than in air-dry phosphogypsum. Particle size sorting could account for variability of 222Rn exhalation at repositories. Very high moisture contents could slightly increase 222Rn emanation, but exhalation would likely be reduced due to slow diffusion through porosity of saturated phosphogypsum.

Calcium Sulfate↗
PubMed1996

Complete decay of radionuclides: implications for low-level waste disposal in municipal landfills.

The time required for the complete decay of a radioactive source can be quantified by specifying an acceptable probability and using an original derivation. The physical phenomenon of complete decay may be used as the technical basis to change regulations and permit, with public acceptance, the inexpensive disposal of short half-lived radioactive waste into municipal landfills. Current regulations require isolation of trash from the biosphere for 30 years during the post-closure control period for municipal landfills. Thirty years is sufficient time for complete decay of significant quantities of short-lived radionuclides, and there is a large decay capacity in the nation's landfills. As the major generators of low-level radioactive waste with relatively short half-lives, the academic, medical, and research communities likely would benefit most from such regulatory relief. Disposal of such waste is prohibited or costly. The waste must be specially packaged, stored, transported, and disposed in designated repositories. Regulatory relief can be initiated by citizens since the Administrative Procedures Act gives citizens the right to petition for regulatory change.

Radioactive Waste↗
PubMed1997

Issues in establishing an aerosol radiological baseline for the waste isolation pilot plant near Carlsbad, New Mexico.

The Department of Energy has constructed a deep geologic repository for defense transuranic waste disposal. The Waste Isolation Pilot Plant, located in Southeastern New Mexico, is slated to receive transuranic waste by truck delivery beginning in 1998. The Environmental Evaluation Group (EEG) provides an independent evaluation of the impact on the health and environment in New Mexico of the WIPP project. Since 1985, the EEG has operated a network of air monitoring sites around WIPP and in nearby communities. The radionuclide concentration data from these air samples have been assembled into a useful baseline data base after resolution of a number of methodological and quality assurance issues. Investigation thresholds for the principal radionuclides have been calculated from combined data collected from several sites. These action levels will provide a critical quantitative basis for decisions of whether future airborne radionuclide measurements are attributable to accidental releases.

Air Pollutants, Radioactive↗
PubMed2002

Volume and activity of buried transuranic-contaminated wastes at U.S. Department of Energy facilities.

From the 1940's through the 1970's, radioactive wastes meeting the current definition of transuranic wastes were disposed of by shallow land burial and other techniques at a number of sites owned and operated by the federal government in support of the nuclear weapons program. After transuranic wastes were identified as a separate category of radioactive wastes (distinct from low-level wastes) in 1970 by the U.S. Atomic Energy Commission, they were generally segregated and placed in retrievable storage pending the availability of a geologic repository. Updated information on buried transuranic wastes was recently developed to support future decisions on how to manage these materials. This paper summarizes the approach used to develop this information for U.S. Department of Energy facilities and presents the volumes and transuranic activities of these wastes. The total volume of buried transuranic wastes at DOE sites is approximately 126,000 m3 with a much smaller volume (about 11,000 m3) disposed of at intermediate depths. The reported transuranic activity in these previously disposed of wastes is about 28,000 TBq.

Radioactive Waste↗
PubMed2006

Using record review as a quality improvement process.

A patient's record is a repository of personal data, the plan of care, and documentation of assessment and treatment. The record review process can facilitate a clinician's understanding about documentation standards and requirements as well as help to maintain a state-of-audit readiness of the record for regulatory and accrediting surveys.

Accreditation↗
PubMed1996

The Iowa CHMIS (Community Health Management Information System): work in progress.

The Iowa Community Health Management Information System (CHMIS) is a legislatively authorized system that is designed to meet Iowa's shared information needs and reduce administrative costs. A public/private partnership has been planning this system for over three years, implementation is scheduled to begin in July 1996. At that time, certified transaction networks will route claims data between providers and payors, a subset of that data will be stored by a centralized data repository. As the system evolves, provider access will be expanded and additional data elements will be captured.

Community Networks↗
PubMed1999

Standardization in endoscopic reporting: implications for clinical practice and research.

The large number of endoscopies and endoscopic reports produced in the United States represents a large repository of clinical data. However, reports are highly variable in content and structure and therefore cannot be used to create clinical databases. The introduction of automated endoscopic reporting systems should permit database creation only if acceptable standards for the structure and content of the report are developed. The structure of an endoscopic report is the framework in which the specific details of the endoscopy can be recorded. The basic components can consist of the following: Patient, Visit, Study, Result, Diagnosis, and Recommendation. Precise definition of each of these components requires consensus on what the minimum included elements should be. Experience with the Minimal Standard Terminology indicates that it is possible to create a broadly acceptable lexicon of descriptive endoscopic terms which can be included as a Result. The systematic development of the structure and content of endoscopic reports is mandatory before it is possible to create large, clinically useful databases of endoscopic reports.

Databases, Factual↗
PubMed1976

Impact of the seclusion room experience.

The seclusion room is a repository of intense feeling and strongly held opinion for members of psychiatric inpatient units. Patients, nurses, and doctors often find themselves in intrapsychic and/or interpersonal conflict over its use and misuse. Perhaps because of general discomfort, relatively little is known about what a patient actually experiences while secluded. In this report, we utilized an unexpected source of information on the meaning of the seclusion room experience for our patients: their art productions. The observations are based upon our therapeutic and research experience with acutely schizophrenic patients hospitalized on an NIMH clinical research unit located in NIH's Clinical Center. On this unit, pharmacotherapy was not used during investigation periods and, in keeping with the unit's treatment philosophy, was used sparingly or not at all during noninvestigative periods. As a result, the seclusion room was used frequently for severe management problems. Systematic collection of art productions was a routine part of the research protocol. Patients attended three individual art therapy sessions: during drug-free periods 2 to 3 weeks after admission, 2 to 3 weeks before discharge, and at follow-up 1 year after admission. The patient was asked to use pastels to draw the following pictures: a free picture (patient's choice), a self-portrait, a picture of his/her psychiatric illness, a picture of any hallucination experienced, and a picture of any delusion experienced. After completing each picture, the patient was encouraged to discuss it. Sixty-two patients were evaluated with this methodology. Particulary noteworthy is the fact that in no instance was a patient requested to draw a picture about a seclusion room experience. Nevertheless, over one third of the patients did so, underscoring the prominence of the experience for them. Furthermore, these pictures did not emerge from a large array of patient art, but from only threee art sessions per patient. The nature of the pictures fell into the following patterns: a) pleasurable hallucinations occurring while in seclusion; b) frightening delusions connected with the experience of seclusion; c) strong nondelusional feelings about being in seclusion (often the picture of the psychiatric illness was a representation of the seclusion room experience); d) special focus on the staff member in attendance outside the seclusion room door. The implications of these graphic expressions are discussed, with particular emphasis on the impact of the seclusion room experience for the patient.

Adolescent↗
PubMed1997

Psychotic experience and disordered thinking: a reappraisal from new perspectives.

The reports of a person suffering from loose associations and disordered behavior serve as the basis for a phenomenology of some central components of psychotic experience. Especially salient are "the expansion of the horizon of meanings," "the emergence of explicit experiences from implicit ones," and "the reduction of complexity." The phenomenological concepts thus developed supplement recent discoveries in neuroscience and experimental psychopathology. Cognitive neuroscientists have depicted the surface of the brain as a repository of self-organizing cortical maps of mental life. Furthermore, experimental psychopathologists have characterized semantic associative networks in normal experience and in psychosis. The authors conclude by joining the phenomenology of psychotic consciousness with the findings of these neuroscientists and experimental psychopathologists.

Adult↗
PubMedDate not supplied

Newly mapped gene for thoracic aortic aneurysm and dissection.

Thoracic aortic aneurysm and dissection (TAAD) is associated with high mortality and medical expense. These poor outcomes are preventable by surgical repair; however, identifying at-risk individuals is difficult. Researchers are actively surveying the human genome (the repository of human genes) to characterize the genetic determinants of TAAD by identifying chromosomal regions likely to harbor such predisposing genes. In previous studies, investigators identified genetic markers shared by a subset of families who were ascertained to have the disease, which clustered into 2 chromosomal regions: 5q13-q15 (TAAD1) and 11q23.2-q24 (familial aortic aneurysm [FAA1]). In a subsequent study, a third chromosomal region at 3p24-25 (TAAD2) was found to contribute to TAAD in a 4-generation, 52-member family that displayed little evidence of sharing either the TAAD1 or FAA1 regions. Although additional regions of the genome may contribute to TAAD, investigators are focusing their efforts on identifying the actual genes and the specific mutations that participate in the disease process. The goal of these endeavors is to develop screening tests to identify individuals at risk for familial TAAD. This genetic discovery has significant clinical implications because high-risk individuals and families can be closely monitored and can benefit from preventative surgical repairs.

Aortic Dissection↗
PubMed2004

Chondroitin sulfate hydrogel and wound healing in rabbit maxillary sinus mucosa.

OBJECTIVES/HYPOTHESIS: Chondroitin sulfate (CS) is a glycosaminoglycan in the extracellular matrix of all vertebrates. A biocompatible, nonimmunogenic, pliable hydrogel preparation of CS has recently been produced and has shown benefit in wound healing in murine and porcine epidermis. The objective of the current experiment is to compare the wound healing properties of CS hydrogel versus no treatment in wounds of the maxillary sinus mucosa. STUDY DESIGN: Prospective investigation in an animal model. METHODS: A 6 mm wound was created in bilateral maxillary sinuses of 17 New Zealand white rabbits. CS hydrogel (case) and no dressing (control) were randomly assigned to one side each as wound treatment. Wounds were examined ex vivo at 2, 4, 6, 10, and 14 day postinjury intervals. Wound diameter was measured microscopically by a blinded investigator. Representative specimens were examined histologically. RESULTS: The CS disc was partially integrated into the wounds at the 4-day interval and completely integrated by the 6-day interval. The average wound diameters for the case versus control side were similar at 2 days (3.75 mm vs. 4.42 mm) but differed significantly at 4 days (2.86 mm. vs. 3.80 mm., P =.035). At 6 days, the wounds could not be discerned on either the case or control sides. However, histologic analysis revealed accelerated healing with the CS treatment. The treated wounds displayed respiratory epithelium as opposed to the squamous epithelium exhibited on the untreated sides. CONCLUSIONS: Despite some limitations, the New Zealand white rabbit is an effective model for the study of sinonasal wound healing. CS hydrogel accelerates wound healing in sinonasal mucosa at a 4-day endpoint. We propose that the CS hydrogel acts as a surrogate extracellular matrix, serving as a repository for cytokines and growth factors produced by the regenerating mucosa. It may also provide a structural framework for fibroblasts and epithelial regeneration. Further study is necessary to establish this relationship.

Animals↗
PubMed2002

The National Library of Medicine.

The National Library of Medicine, located in Bethesda, MD, is the largest repository of medical literature in the world. Its vast holdings now comprise 2.3 million volumes and 3.6 million additional items, including manuscripts; photographs, prints, and other pictorial material; and extensive collections of microfilmed and audiovisual records. Today, this world-famous library faces a range of challenges related to the storage of the formidable volume of new material from around the world, the preservation of older documents, and the demand for technology-driven dissemination of information.

History of Medicine↗
PubMedDate not supplied

Customer-driven outcomes: a patient and family perspective.

Experiencing the healthcare system during an acute surgical event highlighted factors that contributed to customer-driven outcomes. Communicating intentions of and rationale for interventions increased the patient and family's confidence, and engaged the whole mind-body connection into the healing process. Utilizing the family as a repository of patient information incorporated their perspective, knowledge, and wisdom into the delivery and evaluation of patient care. Lastly, fostering the relationship between the nurse and the patient and family strengthened the therapeutic process, thus providing a foundation for customizing care.

Clinical Competence↗
PubMed2001

Comparison of the coulometric and polarographic measurement of a high-Dk hydrogel.

BACKGROUND: International Organization for Standardization (ISO) document ISO 9913-1 details procedures for oxygen permeability coefficient (Dk) measurement of hydrogel contact lens materials up to 100 barrer. A draft ISO document 9913-2 describing the coulometric technique states that the recommended procedures are suitable for nonhydrogel materials. New generation hydrogel lens materials exceed 100 barrer, which is outside the scope of both documents. METHODS: A range of rigid gas-permeable materials from Dr. W. Benjamin's standard repository was used as a baseline to assess the accuracy of the polarographic and the coulometric methods. We also measured the permeability of a new generation hydrogel, lotrafilcon A, to explore the suitability of the polarographic and coulometric techniques for high-Dk hydrogel lenses. We modified equipment for both methods that incorporate several improvements including front surface masking to eliminate "edge effect." RESULTS: The coulometric technique provided results similar to those previously reported for the standard rigid gas-permeable materials and yielded relative standard errors typically <10%. The polarographic technique provided results similar to the accepted values for the standard rigid gas-permeable materials Dk <70 barrer only after the edge effect correction algorithm was applied. The polarographic results showed poor precision and significant, systematic differences from accepted values for the rigid gas-permeables with Dk > 70 barrer. CONCLUSIONS: The coulometric method is preferable for the measurement of contact lens materials with permeability >70 barrer. The coulometric method was successfully modified to include hydrogels.

Contact Lenses, Hydrophilic↗
PubMed1999

Serum vitamin A concentrations in a North American cohort of human immunodeficiency virus type 1-infected children. National Institute of Child Health and Human Development Intravenous Immunoglobulin Clinical Trial Study Group.

BACKGROUND: Vitamin A deficiency is associated with increased risks of vertical transmission of HIV-1 (HIV) and of disease progression and mortality among HIV-infected adults. The objectives of the study were to describe serum vitamin A concentrations among HIV-infected children in the National Institute of Child Health and Human Development IVIG Clinical Trial, to examine changes in vitamin A concentrations and to investigate the relationships between vitamin A concentrations and morbidity and mortality. METHODS: Blood was collected from children at baseline and at 3-month intervals throughout the study. Serum samples were stored at -70 degrees C at a central repository until retrieved for vitamin A assay. Samples were hexane-extracted and assayed by high performance liquid chromatography. The rate of change in vitamin A concentrations, calculated by fitting a linear regression model, was expressed as micrograms/dl/year. RESULTS: The median vitamin A concentration at baseline (n = 207 children) was 31.0 microg/dl [range, undetectable (< 10 microg/dl) to 98 microg/dl]. The rate of change in vitamin A concentrations (n = 180 children) did not vary significantly by any factor other than baseline vitamin A concentration. Baseline vitamin A concentration was not associated with morbidity (incidence of infections, growth failure, CD4+ percent decline below 15%, increases in serum HIV RNA concentrations above either 10(5) or 10(6) copies/ml or acute care hospitalization). Neither baseline vitamin A concentration nor the rate of change of vitamin A concentrations was associated with mortality. CONCLUSIONS: Among these North American children with relatively normal vitamin A concentrations, vitamin A was not observed to be associated with morbidity or mortality.

AIDS-Related Opportunistic Infections↗
PubMed2001

The craniofacial anomalies archive at St. Louis Children's Hospital: 20 years of craniofacial imaging experience.

This article describes how the Craniofacial Imaging Laboratory at the Cleft Palate and Craniofacial Deformities Institute, St. Louis Children's Hospital, Washington University Medical Center, has developed an electronic archive for the storage of computed tomography image digital data that is independent of scanner hardware and independent of units of storage media (i.e., floppy disks and optical disks). The archive represents one of the largest repositories of high-quality computed tomography data of children with craniofacial deformities in the world. Archiving reconstructed image data is essential for comparative imaging, surgical simulation, quantitative analysis, and use with solid model fabrication (e.g., stereolithography). One tertiary craniofacial center's experience in the establishment and maintenance of such an archive through three generations of storage technology is reported. The current archive is housed on an external 35-GB hard drive attached to a Windows-based desktop server. Data in the archive were categorized by specific demographics into groups of patients, number of scans, and diagnoses. The Craniofacial Imaging Laboratory archive currently contains computed tomography image digital data for 1827 individual scans. The earliest scan was done in 1980; the most recently stored scan for the purposes of this report occurred in May of 2000. The average number of scans archived per complete year was 94, with a range of 59 to 138. Of the 1827 total scans, 74 percent could be classified into specific diagnostic categories. The majority of the archive (55 percent) is composed of the following five diagnoses: sagittal synostosis (17 percent), unilateral coronal synostosis (11 percent), hemifacial microsomia (10 percent), plagiocephaly without synostosis (10 percent), and metopic synostosis (7 percent). Storage of computed tomography image data in a digital archive currently allows for continuous upgrading of image display and analysis and facilitates longitudinal and cross-sectional studies, both intramural and extramural. Internet access for clinical and research purposes is feasible, but contingent on protection of patient confidentiality. The future of digital imaging regarding craniofacial computed tomography scan storage and processing is also discussed.

Child↗
PubMed1987

Apparent difference in the roles of spleen and lymph nodes in the pathogenesis of host-versus-graft disease in murine parent/F1 chimeras.

Host-versus-graft (HVG) disease is the often fatal immunodeficiency syndrome that can be induced in susceptible strains of mice by the perinatal inoculation of semiallogenic spleen cells. To determine the distribution and engraftment of the donor cells in the spleens and lymph nodes of RFM hosts, sequential tests were done for the presence of (T6 X RFM)F1 cells marked by their ability to form donor-specific antibodies to horseradish peroxidase (HRP) and by the T6 chromosome. Quantitation of cells with intracytoplasmic antibody that bound HRP (HRPBC) and of metaphases with the T6 marker showed that greater than 90% of donor cells were located in the hyperplastic lymph nodes. The pattern of sequential changes in numbers of HRPBC corresponded with the rise and fall in titers of antibodies to HRP. The marked differences in localization of donor cells suggested that host nodes and spleens played different roles. The lymph nodes became the main sources of donor antibodies and the principal repositories of (T6 X RFM)F1 cells capable of replication. The spleen evidently served as a major site of host resistance to engraftment. This was attributed to the ability of host cells there to inhibit selectively the proliferation of the semiallogenic donor cells. It is also proposed that counts of HRPBC measured the vigor of the HVG reaction in host spleen and lymph nodes, because the appearance of virtually all these antibody-forming cells was the result of the maturational effect of the allogenic reaction on F1 donor B memory cells.

Animals↗
PubMed2001

Role of reentry of in vivo alloMHC peptide-activated T cells into the adult thymus in acquired systemic tolerance.

BACKGROUND: T cell recognition of alloMHC peptide presented by self dendritic cells via the indirect pathway of allorecognition in the thymus induces T cell tolerance. Most recently we have shown that the i.v. administration of immunodominant Wistar Furth MHC class I (RT1.Au) peptide 5- (P5) pulsed myeloid or lymphoid dendritic cells induces operational tolerance to a fully MHC-mismatched cardiac allograft. This finding led us to hypothesize that circulation of peripheral P5-activated T cells to the thymus plays an important role in the induction of acquired tolerance. METHODS: We used the adoptive transfer of 111Indium-oxine- (111In-oxine) labeled P5-pulsed syngeneic dendritic cells and in vivo P5-activated syngeneic T cells to study the role of their circulation to the thymus in the induction of transplantation tolerance. RESULTS: Intravenously administered 111In-oxine-labeled naïve DC actively migrated to and localized in the liver and spleen but did not enter the lymph nodes, bone marrow, and thymus. In vitro peptide-pulsed dendritic cells had a similar pattern of tissue localization except for a modest number of myeloid but not lymphoid DC entering the thymus. The demonstration that adoptive transfer of in vivo peptide-primed T cells induces permanent graft survival in antilymphocyte serum transiently immunosuppressed syngeneic secondary hosts led us to examine the traffic of in vivo activated T cells. Whereas naïve syngeneic T cells preferentially homed to the peripheral lymphoid organs, they did not reenter the thymus. In contrast, in vivo peptide-activated peripheral T cells migrated to and accumulated in the thymus, thus confirming that reentry of T cells to the thymus is restricted to in vivo activated T cells. Although antilymphocyte serum immunosuppression significantly reduced circulation of primed T cells to the thymus, it did not completely abolish it, as seen with gamma-irradiated primed T cells. CONCLUSION: These findings provide the first formal evidence directly linking reentry of in vivo alloMHC peptide-activated T cells to the thymus with the induction and possibly maintenance of acquired antigen-specific tolerance. Our results suggest that the thymus is open to a two-way traffic with the periphery and may function as a repository of immunological memory.

Adoptive Transfer↗