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Mechanical activation has become a phenomenon of general significance in pharmaceutics. This report describes the extent of activation induced by relevant processes. With the use of the Eyring equation the transformation of structurally stored energy into chemical energy and the implied free enthalpy as well as the excess free enthalpy (activity) were evaluated from the rate of an indicator reaction. A comparison was made between different kinds of milling and tabletting with respect to pharmaceutical conditions. An optimization of these processes was derived.  相似文献   
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Summary [3H] UK-14,304 was used to investigate 2-adrenoceptors in rat brain and human platelets. Receptor pharmacology revealed that the ligand binds with high affinity to 2-adrenoceptors. Psychoactive substances like neuroleptics, antidepressants, and-carbolines displace [3H] UK-14,304 from its binding sites in the lower micromolar range. A Hill number around 2 for most neuroleptics suggests a positive cooperativity with the 2-adrenoceptors.Comparative studies with [3H] UK-14,304 and [3H] clonidine utilizing platelet membranes from human volunteers demonstrated that the former ligand is more suitable to investigate possible changes of 2-adrenoceptors; [3H] UK-14,304 labels more receptors with a lower standard deviation, whereby the volume of the blood sample amounted to 35 ml instead of 50 ml required for [3H] clonidine as ligand. No sex differences of binding constants were detected, however an inverse correlation of maximum number of binding sites and affinity was found for female subjects with both ligands.No age-dependent changes of Bmax and KD-values were observed in the range of 24 to 59 years.  相似文献   
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Summary The effects of barbiturates on the GABA-receptor complex and the A1 adenosine receptor were studied. At the GABA-receptor complex the barbiturates inhibited the binding of [35S]t-butylbicyclophosphorothionate ([35S]TBPT) and enhanced the binding of [3H]diazepam. Kinetic and saturation experiments showed that both effects were allosteric. Whereas all barbiturates caused complete inhibition of [35S]TBPT binding, they showed varying degrees of maximal enhancement of [3H]diazepam binding; (±)methohexital was identified as the most efficacious compound for this enhancement. At the A1 adenosine receptor all barbiturates inhibited the binding of [3H]N6-phenylisopropyladenosine ([3H]PIA) in a competitive manner. The comparison of the effects on [3H]diazepam and [3H]PIA binding showed that excitatory barbiturates interact preferentially with the A1 adenosine receptor, and sedative/anaesthetic barbiturates with the GABA-receptor complex. It is speculated that the interaction with these two receptors might be the basis of the excitatory versus sedative/anaesthetic properties of barbiturates.Abbreviations GABA -aminobutyric acid - TBPT t-butylbicyclophosphorothionate 1073 - DMBB 5-(1,3-dimethyl)butyl-5-ethylbarbituric acid - MCB N-methyl-5-(1-cyclohexen-1-yl)-5-ethylbarbituric acid - MPPB N-methyl-5-phenyl-5-propylbarbituric acid - PIA N6-phenylisopropyladenosine Send offprint requests to M. J. Lohse at the above address  相似文献   
106.
The contribution of structural free space to the solvent power of water was examined by a systematic modification of the geometric factor. Gaps and holes, available to foreign molecule occupation, are thought to be filled at low concentrations (max. 1 %) of aliphatic alcohols. The effect upon solvency reached approximately 10%, which suggests that spatial parameters affect solvent power. The results demonstrate the importance of solvent purity in the dissolution process.  相似文献   
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The COVID-19 pandemic has focused health systems on supporting patients affected by this virus. Meanwhile in the community, many other contained patients could only use self-care strategies, especially in countries that have set up a long and strict containment such as France. The study aimed to compare coping strategies deployed by patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS; a poorly recognised syndrome) to those with better known and referenced chronic conditions. An online flash survey was conducted during the containment period in partnership with French Patients Organizations including ME/CFS national association. Therefore, ‘Brief COPE’ version of Lazarus and Folkman's Ways of Coping Check List has been adapted to the specificity of the containment. The survey was e-distributed in France from 15 April to 11 May 2020. Differences of coping strategies were analyzed using Wilcoxon–Mann–Withney test. Amongst 637 responses, 192 were complete, presenting a wide variety of diseases, including 93 ME/CFS. The latter have significantly different coping strategies than recognised diagnosed diseases patients: similar uses of emotion focused coping but less uses of seek social support and problem-focused copings. In conclusion, coping strategies are different for those who deal with the daily experience of ME/CFS, highly disabling chronic condition with diagnostic ambiguity, low degree of medical and social recognition and without treatment. Better understanding of those strategies is needed to provide the means for health promotion researchers, managers and clinicians, to accompany those patients.  相似文献   
108.
European Journal of Epidemiology - Background: Meta-analyses of randomized controlled trials have shown that vitamin D supplementation reduces cancer mortality by 13%. Vitamin D fortification of...  相似文献   
109.
Maternal and Child Health Journal - Colonization with Group B Streptococcus in pregnancy is a major risk factor for neonatal infection. Universal screening for maternal streptococcal colonization...  相似文献   
110.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Vor dem Hintergrund der derzeitigen COVID-19-Pandemie entstand die Idee zur Durchführung einer Studie, in der die...  相似文献   
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