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1.
The combination of a responsive hydrogel with a rigid porous supporting structure yields a membrane with high mechanical strength and high on-off-permeability ratio. A membrane consisting of an ion track filter with a thermally responsive lining was prepared by penetrating a 19 μm thick foil of poly(ethylene terephthalate) (PET) with swift heavy ions at a fluence of 5·105 ions/cm2, followed by etching of the ion tracks to generate an ion track filter with 2.9 μm pore diameter, onto which a thin layer of poly(N-isopropylacrylamide) (NIPAAm) hydrogel was grafted. It was revealed that the mass flow of various molecules (water, chloride, choline+, insulin, and albumin) through the membrane could be thermally controlled. The on-off-permeability ratio ranged between 3 and 10 increasing with molecular weight. Over a storage time of 5 months the permeabilities varied up to a factor of 2.6, while the on-off-permeability ratio and temperature sensitivity remained practically constant.  相似文献   
2.
Metabolic Brain Disease - Acetylcholine is an excitatory neurotransmitter that modulates synaptic plasticity and communication, and it is essential for learning and memory processes. This...  相似文献   
3.
Summary Three strains of viruses have been identified as ectromedia virus (EV) based on their origin, clinical features, morphology, size of virions (140×220nm), replicative ability and specific cytoplasmatic fluorescence. The mean diameter of plaques produced by EV strains was 0.76mm (range 0.5–1.0mm). The neutralizing properties of the tested sera were evaluated by seroneutralization (SN) and hemagglutination inhibition (HAI) tests.  相似文献   
4.
Studies of myocardial metabolism by rapidly catabolized fatty acids like omega-I-123-heptadecanoic acid (IHA) are usually limited to one planar view of require sophisticated equipment, such as bidirectional slant-hole collimators or seven-pinhole collimators for multiplane or tomographic views. To solve this problem a normal SPECT camera was utilized to acquire sequentially sampled dynamic studies from up to six different views. This was done by a periodically repeated sequence of acquisitions in different projections, which followed one another clockwise. This procedure overcomes the single-plane limitations of the usual IHA dynamic studies. It reveals regional myocardial patterns of tracer uptake and elimination not obtainable from any single viewing angle. In this way one methodological disadvantage relative to thallium perfusion studies is removed. Furthermore, the non-invasive diagnosis of cardiomyopathies, for which no other radioisotope procedure is appropriate, should be improved using this new method.  相似文献   
5.
W H Traub  M Spohr  D Bauer 《Chemotherapy》1986,32(3):270-285
Ampicillin, fusidic acid, gentamicin, imipenem, mezlocillin, ofloxacin, penicillin G, piperacillin, and vancomycin were examined for inhibitory and bactericidal activity in various broth media against 7 clinical isolates of Streptococcus faecalis. On a weight-for-weight basis, ampicillin, imipenem, mezlocillin, and ofloxacin proved to be more efficacious. All enterococcal isolates were resistant against gentamicin; fusidic acid and vancomycin lacked bactericidal activity. The combinations of either ampicillin, imipenem, mezlocillin, ofloxacin, piperacillin, or vancomycin with a subinhibitory concentration (4 micrograms/ml) of gentamicin, with or without added 65% (v/v) fresh defibrinated human blood, respectively, yielded additive effects against all enterococcal isolates. The addition of fresh human blood failed to enhance the antienterococcal activity of 4 micrograms/ml of gentamicin; in contrast, addition of 65% (v/v) fresh or heat-inactivated (56 degrees C, 30 min) normal rabbit, bovine, and human sera augmented the activity of gentamicin, an effect that was ablated through the addition of either 0.005 M DTT or 0.01 M MgCl2 + 0.01 M EGTA + 0.01 M CaCl2, supplements known to antagonize human serum beta-lysin, but not lysozyme activity.  相似文献   
6.
For legally binding assessment of reduced earning capacity after loss of spleen in adolescents and adults--in accordance with the Federal German compulsory accident insurance regulations--the article offers a brief review of expertising practice and then proceeds to examine dogmatically which of the cases of subsequent damage after loss of spleen are relevant according to German social security laws. The risk covered by Federal German compulsory accident insurance is critically discussed while bearing in mind that assessment of reduced earning capacity is done exclusively under the viewpoint of objectifiable functional losses.  相似文献   
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Within an interdisciplinary research project, the long-term outcome of children with fetal alcohol syndrome was studied. Methods for the assessment of psychopathology, behavior, and intelligence included psychiatric interviews, behavior checklists for parents and teachers, and intelligence tests. The children were assessed during preschool age, early school age (6 to 12 years), and late school age (≥ 13 years). An excess of psychopathology, (including hyperkinetic disorders, emotional disorders, sleep disorders, and abnormal habits and sterotypies) with a strong persistence over time was found. Cognitive functioning was marked by a large proportion of mentally retarded children and also did not change considerably over time. This long-term outcome study reflects the handicapping effects of fetal alcohol syndrome.  相似文献   
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10.
W H Traub  K H Kohl  M Spohr  D Bauer 《Chemotherapy》1988,34(3):195-201
Polymyxin B (PB) and polymyxin B nonapeptide (PBNP), when combined with rifampin or novobiocin, but not vancomycin, yielded additive inhibitory effects against test strains of Serratia marcescens of three varieties: those that produced cocarde growths around PB disks (coc+); those that grew adjacent to PB disks (coc-, 6); and those that yielded clear inhibition zones around PB disks (coc-, clear). However, time kill curve experiments disclosed that only the combination of rifampin + PB exerted a potent bactericidal effect against coc+ strains of S. marcescens; rifampin + PBNP and novobiocin + PB or PBNP merely effected transient decreases of colony counts. Assays involving 50% (v/v) of fresh defibrinated human blood + PB or PBNP revealed that only PB clearly augmented the antibacterial activity of blood against coc+, and less so against coc- test strains of S. marcescens.  相似文献   
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