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31.
Claus Jacob Alexander Y. Safronov Sonia Wilson H.Allen O. Hill Tim F. Booth 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》1997,431(1):7-10
A novel chiral redox-active ferrocene compound (FcVI) with amphiphilic properties has been synthesized. Cryogenic Transmission Electron Microscopy (cryo-TEM) has been used to estimate the shape and size of the FcVI aggregates in solution. Uni- and multi-lamellar vesicles (between 40 and 300 nm in diameter) were observed in water. Large particles (of more than 1 μm in diameter) with a hexagonal fine structure were found in 50 mM aqueous Na2SO4 solution. Sonication transformed the latter into ‘rosette’-like structures. Cyclic voltammetry has been employed to investigate the electrochemical properties of FcVI. The amphiphile adsorbed on graphite electrodes and a reversible electrochemical behaviour, characteristic of ferrocene, was observed with redox potentials between 330 and 350 mV. 相似文献
32.
Familial Sneddon's syndrome 总被引:4,自引:0,他引:4
Alexander Lossos Tamir Ben-Hur Ziva Ben-Nariah Claes Enk Moshe Gomori Dov Soffer 《Journal of neurology》1995,242(3):164-168
We report the familial occurrence and apparent autosomal dominant inheritance of Sneddon's syndrome with variable clinical expression. The proband, a 40-year-old woman, presented with livedo reticularis and progressive neurological deterioration following a stroke. The diagnosis was confirmed by cerebral angiogram and skin biopsy, both showing the characteristic findings. Two of the patient's sisters were reported to have been similarly affected in the past. Her mother, two additional siblings and five of her seven children exhibited various vasospastic skin phenomena. Familial aggregation of this disorder may be common and a genetic basis may be involved in its pathogenesis. 相似文献
33.
In his autobiography, Dr. Wilder Penfield relates the medical history of his sister, Mrs. Ruth Inglis, who developed a right frontal oligodendroglioma. Penfield performed the initial craniotomy on her, and after her death, reported the case in a paper on frontal lobe function in humans. Although Penfield has provided more than adequate information on certain aspects of his sister's illness, little has been published concerning her subsequent operation performed by Dr. Harvey Cushing at the Peter Bent Brigham Hospital. We feel this case is significant for several reasons. First, it sheds some light on Penfield's personal relationship with Cushing and his sister; it also shows the deep interest that Dr. Cushing took in his patients. Second, this case nicely illustrates how Cushing used his postoperative drawings to make his operative notes more precise. Finally, we see a sample of the work done by Dr. Louise Eisenhardt as pathologist at the Peter Bent Brigham Hospital. 相似文献
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35.
A study of the value of electrophoretic and other techniques for typing Acinetobacter calcoaceticus 总被引:1,自引:0,他引:1
Forty-four isolates of Acinetobacter calcoaceticus var anitratus collected during hospital outbreaks were studied using polyacrylamide gel electrophoresis (PAGE), plasmid analysis, antibiograms and biochemical tests to determine their degree of similarity. Reproducibility tests were also carried out on the PAGE and biochemical techniques to determine their validity when used to compare bacteria of the same type isolated intermittently. PAGE data was analysed densitometrically and isolates compared using a similarity matrix. All methods were able to subdivide the isolates, but results did not always correlate well between methods. Reproducibility data indicated that careful attention to technique is required when organisms are examined by PAGE sequentially. Results suggest that no single biotyping technique is likely to be adequate and that electrophoretic, biochemical and antibiogram data may complement one another and other epidemiological data in the typing of these organisms. 相似文献
36.
Natriuretic peptide-induced cyclic GMP accumulation in adult guinea-pig cerebellar slices. 下载免费PDF全文
1. Second messenger responses to natriuretic peptides were studied in guinea-pig cerebellar slices by use of radioactive precursors. 2. The rank order of potency of the different natriuretic peptides in generating [3H]-guanosine 3':5'-cyclic monophosphate (cyclic GMP) was atrial natriuretic peptide (ANP) > brain natriuretic peptide (BNP) >> C-type natriuretic peptide (CNP) with EC50 values of 19.5 +/- 8.8 nM for ANP and 169 +/- 41 nM for BNP. CNP induced [3H]-cyclic GMP accumulation only at concentrations greater than 1 microM. 3. An additive response to ANP (1 microM) was observed in the presence of the adenosine receptor agonist, 5'-N-ethylcarboxamidoadenosine (NECA, 10 microM) or the soluble guanylyl cyclase activator, sodium nitroprusside (SNP, 100 microM) for [3H]-cyclic GMP accumulation. 4. ANP, BNP and CNP (all at 1 microM) failed to alter significantly either basal-, forskolin- (10 microM), isoprenaline- (100 microM), or NECA- (10 microM) induced [3H]-cyclic AMP generation. Natriuretic peptides also did not change the [3H]-cyclic AMP steady-state reached after 10 min of treatment with 10 microM forskolin. 5. Natriuretic peptides failed to elicit significant accumulation of [3H]-inositol phosphates at concentrations up to 10 microM. 6. These data are consistent with the presence of ANPA, rather than ANPB or clearance receptors (C-receptors), linked to second messenger cascades in guinea-pig cerebellar slices. 相似文献
37.
The stability of phenytoin in blood collected in plain and serum separator tubes (SSTs) was investigated under simulated storage and transport conditions. The drug was generally more stable in plain collection tubes than in SSTs. No degradation occurred in plain red-top tubes or in refrigerated SSTs, but clinically significant degradation was present in SSTs stored at room temperature (25 degrees C) and at elevated temperature (32 degrees C) 24 h after collection. The mean loss was 17.9% at 25 degrees C and 25.9% at 32 degrees C. It is recommended that if blood is to be transported or stored in SSTs, the samples be refrigerated unless assay can be performed within 8 h. 相似文献
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