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GREGORY JE 《Experimental medicine and surgery》1949,7(4):289-98, illust
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YANNIS L. LOUKAS VASSILIKI VRAKA GREGORY GREGORIADIS 《The Journal of pharmacy and pharmacology》1997,49(2):127-130
The non-linear least-squares model for calculation of the stability constant (Kst) of a drug-cyclodextrin complex has been used in fluorimetry studies. Complexation of riboflavin with β-cyclodextrin (β-CyD) was monitored fluorimetrically by measuring changes in the fluorescence intensity of the vitamin in the presence of various amounts of β-CyD. Formation of an inclusion complex was confirmed in the solid state by differential scanning calorimetry (DSC) and in aqueous solution by proton nuclear magnetic resonance spectroscopy (1H NMR). The experimental Kst value (2112 M?1) derived from the fluorimetry studies appeared to fit well to a 1:1 drug-to-cyclodextrin molar ratio according to the non-linear mathematical model. The model is particularly suitable for fluorescent compounds of which fluorescence intensity is influenced by the presence of cyclodextrins. 相似文献
5.
GUTHRIE ROBERT M; RUOFF GARY E; ROFMAN BARRY A; GINSBERG DAVID; KARP RONDA R; BROWN SHARON M; SHULZ GREGORY A 《Family practice》1988,5(1):29-35
Guthrie R M, Ruoff G E, Rofman BA, Ginsberg D, Karp R R, BrownS M and Schulz GA. Aetiology of acute pharyngitis and clinicalresponse to empirical therapy with erythromycin versus amoxicillin.Family Practice 1988; 5: 2935. One hundred and eighty-nine adults with acute pharyngitis hadculture and serological evaluation for groupA beta haemolyticstreptococci (GABHS), Mycoplasma pneumoniae, and Branhamellacatarrhalis. Sixteen patients had evidence for infection withGABHS, none for M. pneumoniae, and one for B. catarrhalis. Forthose with GABHS, there was no significant difference betweenempirical treatment by erythromycin or amoxicillin. For thosewithout GABHS, empirical treatment with erythromycin appearedto result in a statistically significant reduction in coughand a noticeable but less than significant reduction of othersymptoms when compared to empirical treatment with amoxicillin.The new formula tion of erythromycin utilized in this study(PCE) may be associated with a reduction in gastrointestinalintolerance from that reported with other erythromycin products. 相似文献
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Subchronic Toxicity of Cupric Sulfate Administered in Drinking Water and Feed to Rats and Mice 总被引:2,自引:0,他引:2
HEBERT CHARLES D.; ELWELL MICHAEL R.; TRAVLOS GREGORY S.; FITZ CHAD J.; BUCHER JOHN R. 《Toxicological sciences》1993,21(4):461-475
Subchronic Toxicity of Cupric Sulfate Administered in DrinkingWater and Feed to Rats and Mice. HÉBERT, C. D., ELWELL,M. R., TRAVLOS, G. S., FITZ, C. J., AND BUCHER, J. R. (1993).Fundam. Appl. Toxicol. 21, 461475. The effects of acute poisoning by cupric sulfate in a numberof species are well known; however, the effects of chronic low-levelingestion of cupric sulfate are less well characterized. Becauseexposure of humans to cupric sulfate may occur through drinkingwater, food, soil, or ambient air, subchronic toxicity studieswere conducted in male and female F344/N rats and B6C3F1 miceby the drinking water (2-week exposure) and dosed feed (2-and13-week exposure) routes. Animals were evaluated for histopathology,clinical pathology, reproductive toxicity, and tissue metalaccumulation, and target organs were examined by a variety ofspecial stains and by electron microscopy to characterize theobserved lesions. In drinking water, cupric sulfate concentrationsof 300 to 100 ppm produced no ill effects, whereas concentrationsof 3000 to 30,000 ppm were lethal to rats and mice within 2weeks. In feed, cupric sulfate concentrations of 4000 to 16,000ppm caused significant reductions in body weight gain in bothspecies in the 2- and 13-week studies. Hyperplasia and hyperkeratosisof the limiting ridge of the forestomach were present in bothspecies in the 2- and 13-week studies. Rats in the dosed feedstudies had a dose-related increase in inflammation in the liverand changes in clinical chemistry parameters which were indicativeof hepatocellular damage and cholestasis. Histologic changesin the kidneys of rats consisted of a dose-related increasein the number and size of eosinophilic protein droplets in theepithelial cytoplasm and the lumina of the proximal convolutedtubules. Droplets were larger and more numerous in males thanin females. Urinalysis results were suggestive of renal tubularepithelial damage. Iron staining of spleens from treated animalsindicated a marked depletion of iron stores in both male andfemale rats, but not in mice, while hematologic and clinicalchemistry alterations in rats in the 13-week study, along withhistologic changes in bone in the 2-week dosed feed study, wereindicative of a microcytic anemia. Cupric sulfate produced noadverse effects on any of the reproductive parameters measuredin rats or mice of either sex. These results indicate that cupricsulfate at high exposure levels is a hepatic and renal toxicant,as well as an inducer of anemia in rodents, with rats more sensitivethan mice following subchronic exposure. 相似文献
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GREGORY V. NIKIFOROVICH ALEXANDER A. GOLBRAIKH MARK D. SHENDEROVICH JURIS BALODIS 《Chemical biology & drug design》1990,36(3):209-218
Models of μ- and δ-receptor-bound backbone conformations of enkephalin cyclic analogues containing Phe4 were determined by comparing geometrical similarity among the previously found low-energy, backbone structures of -enkephalinamide, -enkephalinamide, -enkephalin and -enkephalin. The present μ-receptor-bound conformation resembles a β-I bend in the peptide backbone centred on the Gly3-Phe4 region. Two slightly different models were found for the δ-receptor-bound conformation; both of them are more extended than the μ-receptor-bound conformation and include a γ-turn (or a γ-like turn) on the Gly3 residue. Energetically favourable rotamers of Tyr and Phc side chains were also determined for the μ- and δ-conformations. The present models of μ- and δ-conformations share geometrical similarity with the low-energy structures of Leu-enkephalin and the analogue. 相似文献
8.
KONG C. S.; RYDER I. G.; KAHN R.; GREGORY L.; MACKENZIE C. F. 《British journal of anaesthesia》1995,74(2):201-208
We compared in vitro oxyhaemoglobin saturations using two pulmonaryartery catheters (catheter So2) with oxyhaemoglobin saturations(So2) measured by the IL282 co-oximeter and derived partialoxyhaemoglobin saturations (partial So2) at different oxygentensions (Po2) in six solutions: whole blood, 50:50 mixtureof whole blood and Plasmalyte A (haemodiluted blood), 50:50mixture of whole blood and 8% pyridoxylated haemoglobin-polyoxyethylene(PHP) conjugate (WB-PHP), 75:25 mixture of 8% PHP and PlasmalyteA solution (PHP66), 50:50 mixture of 8% PHP and Plasmalyte Asolution (PHP44) and stroma-free haemoglobin solution (SFH).Calculated P50 values (Po2, vs So2) were 3.79, 3.58, 3.49, 3.15,3.04 and 2.07 kPa, respectively. However, if partial So2 wasused the curves were shifted to the left, reducing P50. CatheterSo2 correlated well with So in whole blood (r2 > 0.99 forboth catheters), haemodiluted blood (r2 > 0.98 for both catheters)and WB-PHP solution (r2 = 0.94 for both catheters). In PH P44(r2 = 0.64 and r2 = 0.57), PHP P66 (r2 = 0.40 for the Oximetrixand r2 = 0.25 for the Edwards catheter) and SFH solutions (r2= 0.33 for the Oximetrix and r2 = 0.22 for the Edwards catheter)both catheters performed poorly. We conclude that mixed venousoxyhaemoglobin saturations measured by oximetric pulmonary arterycatheters are inaccurate in the presence of haemoglobin solutions.For accuracy a multi-wavelength co-oximeter should be used ifblood containing PHP or SFH is to be analysed.
Present address: Department of Anaesthetics, Bristol Royal Infirmary,Bristol, UK 相似文献
9.
JEFFREY E. TERRELL MD KINJAL NANAVATI MPH RAMON M. ESCLAMADO MD CAROL R. BRADFORD MD GREGORY T. WOLF MD 《Otolaryngology--head and neck surgery》1999,120(6):852-859
A multidimensional Head and Neck Quality of Life (HNQOL) instrument and a general health status measure were administered to 397 patients with head and neck cancer. Scores for the 4 domains of the HNQOL (communication, eating, pain, and emotional well-being) were calculated. Patient demographics, comorbidities, clinical characteristics, treatment data, disability status, and a global "overall bother" score were assessed. When compared with the US population aged 55 to 64 years, the group had significantly worse scores in the 8 health domains of the SF-36. Patients' overall bother scores from the head and neck cancer treatment correlated best with the HNQOL emotion domain (r = 0.71) and the HNQOL pain domain (r = 0.63), and least with the patients' perception of their response to treatment (r = 0.39). Pain, eating, emotion, physical component summary score, age, and an interaction term between eating and emotion were significant predictors for overall bother. Of the 217 patients who were working before the diagnosis of cancer, 74 (34. 1%) reported that they had become disabled. Patients who had more than 1 type of treatment were 5.9 times more likely to report themselves as disabled (odds ratio [OR] = 5.94, P < 0.01), even after adjusting for age, emotion score, and physical component summary score, which were other factors that predicted disability. 相似文献
10.
The Translocation of Inhaled Silicon Dioxide: An Empirically Derived Compartmental Model 总被引:1,自引:0,他引:1
VACEK PAMELA M.; HEMENWAY DAVID R.; ABSHER MARLENE P.; GOODWIN GREGORY D. 《Toxicological sciences》1991,17(3):614-626
The Translocation of Inhaled Silicon Dioxide: An EmpiricallyDerived Compartmental Model. VACEK, P. M., HEMENWAY, D. R.,ABSHER, M. P., AND GOODWIN, G. D. (1991). Fundam. Appl Toxicol.17, 614626. The movement of inhaled silicon dioxide particleswas studied by measuring the amounts in alveolar fluid and cells,lung tissue, and lymphoid tissue during the 6 months followingshort-term aerosol exposure of Fischer 344 rats. A variety offirst-order compartmental models were fit to data from nineexposure experiments to identify the most feasible biologicpathways for the transfer of material among these sites andout of the body. A multivariate least-squares approach was usedto simultaneously fit the data from several compartments. Theresults indicate that transfer between alveolar cells and lungtissue occurs in both directions, suggesting that silica canreenter the alveolar space from the lung tissue. This featurehas not been included in previously published models. The resultsalso indicate that transfer from lung tissue to the mediastinallymph nodes and thymus is indirect; there are one or more unidentifiedextrapulmonary compartments that receive silica from the lung.Rates of transfer among compartments were dependent on mineraltype (quartz or cristobalite), heat treatment, and exposuredose. There was no evidence for direct clearance from the alveolarspace via the tracheobronchial tract. 相似文献