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991.
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993.
BACKGROUND: Thyroid hormones are important regulators of brain development. During critical periods of development, even transient disorders in thyroid hormone availability may lead to profound neurologic impairment. Animal experiments have shown that certain environmental pollutants, including heavy metals and organochlorine compounds such as polychlorinated biphenyls (PCBs) and dioxins, can interfere with thyroid hormone homeostasis. Whether these contaminants can affect circulating levels of thyroid hormones in humans is unclear, however, because the results of available studies are inconsistent. OBJECTIVES: The aim of the present study is to examine the possible relationships between concentrations of environmental pollutants and thyroid hormone levels in human umbilical cord blood. METHODS: We measured concentrations of environmental pollutants [including selected PCBs, dioxin-like compounds, hexachlorobenzene, p,p'-DDE (dichlorodiphenyldichloroethylene), cadmium, lead] and thyroid hormones in the cord blood of 198 neonates. RESULTS: A statistically significant inverse relationship between concentrations of organochlorine compounds and levels of both free triiodothyronine (fT3) and free thyroxine (fT4), but not thyroid-stimulating hormone, was observed. We found no association between concentrations of heavy metals and thyroid hormone levels. CONCLUSIONS: Our results suggest that environmental chemicals may affect the thyroid system of human neonates. Although the differences in fT3 and fT4 levels associated with the organochlorine compounds were within the normal range, the observed interferences may still have detrimental effects on the neurologic development of the individual children, given the importance of thyroid hormones in brain development.  相似文献   
994.
Process-based organization design and hospital efficiency   总被引:1,自引:0,他引:1  
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995.
The susceptibilities of 284 anaerobic bacteria, including 55 strains of the Bacteroides fragilis group, were determined by an agar dilution technique to metronidazole and two newer nitroimidazoles, ornidazole and SC-28538. All three agents showed marked in vitro activity against virtually all anaerobic bacteria tested. At concentrations ≤1 μg/ml, SC-28538 was significantly more active than either metronidazole or ornidazole. At concentrations of >1 μg/ml, the activities of all three agents were comparable. Propionibacterium and Actinomyces showed significant resistance to all three agents. Anaerobic and microaerophilic members of the genus Streptococcus were also often resistant, in contrast to Peptococcus and Peptostreptococcus strains. In addition, the bactericidal activities of ornidazole and SC-28538 were determined against 27 strains of the B. fragilis group by a broth dilution technique. The minimal inhibitory and minimal bactericidal concentrations of each agent were very close. At concentrations of ≤0.5 μg/ml, SC-28538 showed greater bactericidal activity; at concentrations of ≥2 μg/ml, the activies of both agents were similar.  相似文献   
996.
Ohne Zusammenfassung Herausgegeben vom Vorstand der Deutschen Gesellschaft für Kardiologie – Herz- und Kreislaufforschung e.V. Bearbeitet im Auftrag der Kommission für Klinische Kardiologie M. Borggrefe, M. B?hm, J. Brachmann, H.-R. Figulla, G. Hasenfu?, H.M. Hoffmeister, A. Osterspey, K. Rybak, U. Sechtem, S. Silber  相似文献   
997.
OBJECTIVE: The aim of this study was to investigate unidimensionality and differential item functioning of the SF-36 physical functioning scale (PF10) in patients with various neurological disorders. Patients: Patients post-stroke (n = 198), with multiple sclerosis (n = 151) and amyotrophic lateral sclerosis (n = 193) participated. METHODS: Unidimensionality of the PF10 within the patient groups was investigated by performing a separate Rasch analysis for each group. Differential item functioning was investigated in a pooled Rasch analysis of the 3 groups. RESULTS: Within each group, all items fitted the Rasch model, except the "bathing/dressing" item in the amyotrophic lateral sclerosis group. The pooled analysis showed inadequate fit to the Rasch model for one item ("walking several hundred metres"). Of the other 9 fitting items, 5 showed differential item functioning for stroke vs multiple sclerosis and amyotrophic lateral sclerosis, while no differential item functioning was found between multiple sclerosis and amyotrophic lateral sclerosis. CONCLUSION: All items of the PF10, except one for the amyotrophic lateral sclerosis group, form a unidimensional scale, supporting the use of a sum score as a measure of physical functioning within these diagnostic groups. When comparing the data of patients after stroke, with that of patients with multiple sclerosis and/or amyotrophic lateral sclerosis patients, adjustments for differential item functioning are required.  相似文献   
998.
The absorption of gabapentin (Neurontin) is dose-dependent and variable between patients. Rapid clearance of the drug necessitates dosing three or more times per day to maintain therapeutic levels. These deficiencies appear to result from the low capacity, limited intestinal distribution, and variable expression of the solute transporter responsible for gabapentin absorption. Saturation of this transporter at doses used clinically leads to unpredictable drug exposure and potentially ineffective therapy in some patients. XP13512 [(+/-)-1-([(alpha-isobutanoyloxyethoxy)carbonyl]aminomethyl)-1-cyclohexane acetic acid] is a novel prodrug of gabapentin designed to be absorbed by high-capacity nutrient transporters located throughout the intestine. XP13512 was efficiently absorbed and rapidly converted to gabapentin after oral dosing in rats and monkeys. Exposure to gabapentin was proportional to prodrug dose, whereas exposure to intact XP13512 was low. In rats, >95% of an oral dose of (14)C-XP13512 was excreted in urine in 24 h as gabapentin. In monkeys, oral bioavailability of gabapentin from XP13512 capsules was 84.2% compared with 25.4% after a similar oral Neurontin dose. Compared with intracolonic gabapentin, intracolonic XP13512 gave a 17-fold higher gabapentin exposure in rats and 34-fold higher in monkeys. XP13512 may therefore be incorporated into a sustained release formulation to provide extended gabapentin exposure. XP13512 demonstrated improved gabapentin bioavailability, increased dose proportionality, and enhanced colonic absorption. In clinical use, XP13512 may improve the treatment of neuropathic pain, epilepsy, and numerous other conditions by increasing efficacy, reducing interpatient variability, and decreasing frequency of dosing.  相似文献   
999.

Background  

Previous studies have suggested that impaired proprioceptive processing in the striatum may contribute to abnormal gait in Parkinson's disease (PD).  相似文献   
1000.
Thirteen independent isolates of Serratia marcescens associated with nosocomial urinary tract infections were obtained from the clinical microbiology laboratory at Hines Veterans Administration Hospital. The isolates were resistant to at least ampicillin, carbenicillin, gentamicin, and tobramycin. They could be divided into two groups on the basis of their antibiotypes. Group I (9 strains) showed resistance to 13 antibiotics, including 3 beta-lactams, 6 aminoglycosides, tetracycline, sulfonamide, trimethoprim, and polymyxin B. Group II (4 strains) was resistant to 11 antibiotics, including 3 beta-lactams, 5 aminoglycosides, sulfonamide, trimethoprim, and polymyxin B. Donors from both groups transferred resistance traits to Escherichia coli. Transconjugants from matings with group II donors all acquired resistance to nine antibiotics, including the three beta-lactams, five aminoglycosides, and sulfonamide. Transconjugants from matings with group I donors were of varied antibiotypes, inheriting resistance to up to 11 of the 13 antibiotics. Resistances to trimethoprim and polymyxin B were never observed to transfer. E. coli transconjugants of each group were capable of transferring multiple-antibiotic resistance to several other members of the family Enterobacteriaceae. All group II S. marcescens and E. coli donors and all group I S. marcescens donors transferred carbenicillin, streptomycin, kanamycin, gentamicin, tobramycin, and sisomicin resistance to Pseudomonas aeruginosa. The results suggest that these S. marcescens strains harbor R factors of a broader host range than previously reported.  相似文献   
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