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31.
Age of onset reports obtained retrospectively for each symptom of DSM-III-R alcohol dependence (AD) are used to study patterns of lifetime symptom progression in a large general-population survey of people in the United States. It is shown that symptom progression among a substantial majority of respondents can be summarized as movement across three clusters. Cluster A is defined by symptoms of role impairment/hazardous use (A4), use despite social, psychological or physical problems (A6), and drinking larger amounts or over a longer period of time than intended (A1). Cluster B is defined by tolerance (A7) and impaired control (A2, A3). Cluster C is defined by withdrawal (A8, A9) and giving up activities in order to drink (A5). Clusters are shown to follow a time sequence, with at least one symptom in Cluster A usually occurring first, followed by symptoms in Clusters B and C. In all, 83.4% of the symptom cluster transitions estimated from retrospective age of onset reports are consistent with this progression. Progression to AD is differentially predicted by symptom profiles reported at the age of first symptom onset, with persons reporting Cluster C symptoms most likely to progress subsequently to AD. Furthermore, profiles of AD defined by the highest symptom cluster present at AD onset are differentially predicted by prior personal and parental histories of psychopathology and, among men, are predictive of diagnosis persistence. 相似文献
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Diabetes mellitus places a significant burden on the U.S. healthcare system. Because of the potential to reduce diabetic complications and costs through intensive management, diabetes has become a primary target for disease management programs. We performed a retrospective analysis of short-term baseline and follow-up clinical, economic, and member and provider satisfaction data from approximately 7,000 people with diabetes being treated through seven managed care plans using Diabetes Treatment Centers of America's Diabetes NetCare, (Nashville, TN), a comprehensive diabetes management program. Our analysis indicates that Diabetes NetCare achieved gross economic adjusted savings of $50 per diabetic member per month (12.3%), with gross unadjusted savings of $44 (10.9%) per diabetic member per month. Hospital admissions per 1,000 diabetic member years decreased by 18%, and bed days fell by 21%. Patients with diabetes were more likely to get HbAlc tests, foot exams, eye exams, and cholesterol screenings while enrolled in the program. These data suggest that implementation of a comprehensive healthcare management program for people with diabetes can lead to substantial improvements in costs and clinical outcomes in the short-term. It is expected that improvements will increase over time, with continuing improvements in health status and a reduction in the number of future diabetic complications. 相似文献
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ME Farago P Kavanagh R Blanks J Kelly G Kazantzis I Thornton PR Simpson JM Cook HT Delves GE Hall 《Canadian Metallurgical Quarterly》1998,123(3):451-454
Increasing Pt concentrations from vehicle catalysts have been reported from a number of countries. Analysis of Pt and Pd in soils and road dusts taken from areas of high and low traffic flows in SE England show concentrations of Pt in the range < 0.30-40.1 ng g-1 and Pd in the range < 2.1-57.9 ng g-1. Higher concentrations of Pt are associated with high traffic densities. Samples taken from streets of lower traffic flows were found to contain the lower concentrations of the ranges. Pilot studies of Pt concentrations in blood and urine using ICP-MS have been carried out. Platinum concentrations in whole blood were: precious metal workers, 780-2170, mean 1263 pmol l-1 (0.152-0.423, mean 0.246 microgram l-1); motorway maintenance workers, 645-810, mean 744 pmol l-1 (0.126-0.158, mean 0.145 microgram l-1); Imperial College staff, 590-713, mean 660 pmol l-1 (0.115-0.139, mean 0.129 microgram l-1). Platinum concentrations in urine in pmol Pt per mmol creatinine were: precious metal workers, 122-682, mean 273 [0.21-1.18, mean 0.47 microgram Pt (g creatinine)-1]; motorway maintenance workers, 13-78, mean 33.7 [0.022-0.135, mean 0.058 microgram Pt (g creatinine)-1]; Imperial College staff, 28-130, mean 65.6 [0.048-0.224, mean 0.113 microgram Pt (g creatinine)-1]. Detection limits were 0.03 microgram l-1 for both blood and urine. The possible health effects of increasing Pt in the environment are discussed. Platinum provides an excellent example of the significance of speciation in metal toxicity. Platinum allergy is confined to a small group of charged compounds that contain reactive ligand systems, the most effective of which are chloride ligand systems. Metallic Pt is considered to be biologically inert and non allergenic and since the emitted Pt is probably in the metallic or oxide form, the sensitising potential is probably very low. Platinum from road dusts, however, can be solubilised, and enter waters, sediments, soils and the food chain. There is at present no evidence for any adverse health effects from Pt in the general environment, particularly allergic reactions. 相似文献
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RJ Wilkinson K Hasl?v R Rappuoli F Giovannoni PR Narayanan CR Desai HM Vordermeier J Paulsen G Pasvol J Ivanyi M Singh 《Canadian Metallurgical Quarterly》1997,35(3):553-557
The diagnosis of infection caused by Mycobacterium tuberculosis is of increased public health concern following increases in the number of cases in developed countries and major increases in developing countries associated with the spread of human immunodeficiency virus (HIV) infection. The specificity of purified protein derivative skin testing for the detection of infection is compromised by exposure to environmental mycobacteria. Examination of sputum detects the most infectious patients, but not those with extrapulmonary disease. The 38-kDa antigen of M. tuberculosis contains two M. tuberculosis-specific B-cell epitopes. We overexpressed the gene for this antigen in Escherichia coli and evaluated the recombinant product in in vitro assays of T-cell function and as a target for the antibody response in humans. The sensitivity and specificity of the antigen as a skin test reagent were also assessed in outbred guinea pigs. We found that 69% of healthy sensitized humans recognize the antigen in vitro, as manifested by both cell proliferation and the production of gamma interferon. Untreated patients initially have a lower frequency of response (38%); this recovers to 72% during therapy. A total of 292 patients (20 with HIV coinfection) and 58 controls were examined for production of antibody to the 38-kDa antigen by using a commercially available kit. The sensitivity of the test in comparison with that of culture was 72.6%, and the specificity was 94.9%. The antigen was also tested for its ability to induce skin reactions in outbred guinea pigs sensitized by various mycobacterial species. The antigen provoked significant skin reactions in M. tuberculosis-, M. bovis BCG-, and M. intracellulare-sensitized animals. The significance of these findings and the usefulness of this antigen in immunodiagnosis are discussed. 相似文献
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RJ Nijman 《Canadian Metallurgical Quarterly》1995,63(2):99-103
For the evaluation of bladder (dys)function in young children with neuropathic bladder or other congenital malformations urodynamic investigations have become widely accepted. Although urodynamic studies can be conducted as early as the newborn period, there are some specific studies that can only be performed in somewhat older children, such as pressure-flow studies. Unlike adult patients, children most often do not understand why such an invasive study needs to be performed and are therefore less co-operative. In order to make the study as pleasant as possible some special measures have to be taken. This paper describes the different modalities available to perform urodynamic investigations in children, its drawbacks, pitfalls, indications, clinical implications and prerequisites. 相似文献
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RJ Bergeron WR Weimar Q Wu Y Feng JS McManis 《Canadian Metallurgical Quarterly》1996,39(26):5257-5266
A series of analogues and homologues of spermine were synthesized, and their impact on MK-801 binding to the N-methyl-D-aspartate (NMDA) receptor was evaluated. These tetraamines encompass both linear and cyclic compounds. The linear molecules include norspermine, N1, N11-diethylnorspermine, N1,N12-bis(2,2,2-trifluoroethyl)spermine, homospermine, and N1,N14-diethylhomospermine. The cyclic tetraamines consist of the piperidine analogues N1,N3-bis(4-piperidinyl)-1,3-diaminopropane, N1,N4-bis(4-piperidinyl)-1,4-diaminobutane, N1,N4-bis(4-piperidinylmethyl)-1,4-diaminobutane, and N1,N4-bis[2-(4-piperidinyl)ethyl]-1,4-diaminobutane and the pyridine analogues N1,N3-bis(4-pyridyl)-1,3-diaminopropane, N1,N4-bis(4-pyridyl)-1,4-diaminobutane, N1,N4-bis(4-pyridylmethyl)-1,4-diaminobutane, and N1,N4-bis[2-(4-pyridyl)-ethyl]-1,4-diaminobutane. This structure-activity set makes it possible to establish the importance of charge, intercharge distance, and terminal nitrogen substitution on polyamine-regulated MK-801 binding in the NMDA channel. Four families of tetraamines are included in this set: norspermines, spermines, homospermines, and tetraazaoctadecanes. Calculations employing a SYBYL modeling program revealed that the distance between terminal nitrogens ranges between 12.62 and 19.61 A. The tetraamines are constructed such that within families cyclics and acyclics have similar lengths but different nitrogen pKa's and thus different protonation, or charge, states at physiological pH. The pKa values for all nitrogens of each molecule and its protonation state at physiological pH are described. The modifications at the terminal nitrogens include introduction of ethyl and beta,beta,beta-trifluoroethyl groups and incorporation into piperidinyl or pyridyl systems. The studies clearly indicate that polyamine length, charge, and terminal nitrogen substitution have a significant effect on how the tetraamine regulates MK-801 binding to the NMDA receptor. Thus a structure-activity basis set on which future design of MK-801 agonists and antagonists can be based is now available. 相似文献