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Hydrophobity (coefficient in distribution in the hexane water system) and the content of cholinesterase organophosphorous inhibitors (OPI) of the structure Ro (CH3) P (O) SC2H4 SC2H5 were studied in the rat brain. When the O-alkyl radical is increased hydrophobity rises and the relative content of free OPI in the brain extracted by chloroform decreases. With an increase in R from the ethyl to butyl one the ability to the additional inhibition of the brain own cholinesterase lowers due to incubation of homogenate at 37 degrees C, that evidences for an essential drop in the studied series of the free OPI fraction relative to the free OPI extracted by chloroform.  相似文献   
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We describe the case of a 26-year-old man with an elevated level of alpha-fetoprotein who had no evidence of intragonadal or extragonadal germ cell tumor. The patient was found to have Hodgkin's lymphoma within an anterior mediastinal mass. We review the significance of elevated alpha-fetoprotein levels and discuss the clinical relevance of this unusual presentation of a possible primary Hodgkin's lymphoma.  相似文献   
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Experiments on white rats revealed that introduction of Ossocol, a sponge with a composition of hydroxyl apatite with collagen, into a removed tooth well prevented mandibular atrophy and was conducive to a more smooth defect filling with better compact bone tissue. Ossocol use in 214 patients with bone tissue defects developing after tooth removal, of odontogenic cysts, sequestra, and after radical surgery for periodontal diseases demonstrated a positive effect of this agent on the course of the postoperative period: the defect was more rapidly replaced by bone tissue. No unfavorable local or general reactions to Ossocol implantation were observed.  相似文献   
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A clinical trial using the experimental gingivitis model developed for periodontal clinical research was performed to evaluate the effect of a removable partial denture mandibular major connector design on the surrounding gingival tissues. A comparison of the state of health of adjacent gingival tissues was made between the linguoplate (control) and cingulum bar (test) major connectors. Clinical parameters were recorded in a single-blind crossover experimental gingivitis trial. Subjects were brought to a level of optimal gingival health and then randomly assigned to use one framework design while refraining from any oral hygiene. Measurements were made at 7-day intervals for 21 days. The subjects were returned to optimal oral health and repeated the experimental period with the alternate design. Results showed a greater increase in mean gingival inflammation with the control than with the test removable partial denture, suggesting that the cingulum bar has fewer detrimental effects on gingival tissues than the linguoplate major connector. Results of this study suggest that the experimental gingivitis model can be a useful and valid system for studying the potential effects of a removable partial denture design on surrounding oral tissues.  相似文献   
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The results of experimental investigations to evaluate the adverse effects of metal-containing industrial waste on warm-blooded animals are presented. Acute experiments assessing the toxicity of industrial waste were not shown to be informative. Long-term exposure to different industrial wastes was found to have varying toxicity at the cell, organ, and body levels.  相似文献   
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OBJECTIVE: To determine the reliability of intraocular pressure (IOP) measurements by Goldmann applanation tonometry and pneumotonometry in eyes treated with excimer myopic photorefractive keratectomy (PRK). DESIGN: A prospective case series. PARTICIPANTS: Forty consecutive eyes treated with PRK were evaluated. INTERVENTION AND MAIN OUTCOME MEASURES: Central and peripheral corneal Goldmann tonometry and pneumotonometry measurements were done before surgery, at 1 week, and at 1 and 3 months after surgery. RESULTS: The IOP by Goldmann tonometry from the central cornea was significantly lower than the peripheral IOP; however, there was no difference between IOP measured from central and peripheral corneas by pneumotonometry, which, in turn, correlated with peripheral Goldmann measurements. There was a trend, but not a statistically significant correlation, between the spherical equivalent of the treatment and the amount of decrease in central Goldmann IOP. CONCLUSIONS: Pneumotonometry measures the IOP reliably after PRK from all parts of the cornea, whereas central Goldmann tonometry underestimates the IOP by 2.40+/-1.23 mmHg.  相似文献   
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