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Uroscopy in the 21st century: high-field NMR spectroscopy 总被引:1,自引:1,他引:0
Neild GH; Foxall PJ; Lindon JC; Holmes EC; Nicholson JK 《Nephrology, dialysis, transplantation》1997,12(3):404-417
From the experiments described, it can be seen that there are different
research approaches that can be taken and these are summarized in Table 1.
Whereas much scientific research is principally hypothesis led, there
remains, nevertheless, an important place for exploratory research. High
resolution NMR can measure, directly and simultaneously, a wide range of
endogenous metabolites in biological fluids and has the unique capability
of providing structural information on the metabolites detected. It has
proved to be a powerful research tool with which to study inherited
metabolic diseases, renal disease, drug metabolism, and toxicity, and can
be used to monitor the effects of drug therapy. For instance, by using a
library of experimental toxins one can map the metabolic profile of
site-specific nephron injury. With this approach in man one could
eventually take an unknown disease such as Balkan nephropathy and predict
the initial site of tubular injury, the mode of injury and therefore the
kind of toxin capable of producing that injury. NMR spectroscopic
techniques are still advancing rapidly, with ever increasing sensitivity
and sophistication of NMR pulse sequences to enhance structural elucidation
in complex mixtures. Given the advances in directly coupled HPLC-NMR and
even HPLC-NMR-mass spectroscopy it is likely that these technologies in
conjunction with pattern recognition will make major contribution to our
understanding of renal processes and provide new diagnostic insights in the
21st century.
相似文献
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van Muiswinkel FL de Vos RA Bol JG Andringa G Jansen Steur EN Ross D Siegel D Drukarch B 《Neurobiology of aging》2004,25(9):1253-1262
Dopamine (DA) autooxidation, and consequent formation of neurotoxic DA-derived quinones and reactive oxygen species, has been implicated in dopaminergic cell death and, hence, in the pathogenesis of Parkinson's disease (PD). Stimulation of pathways involved in the detoxication of DA-quinones in the brain is hypothesized to be an effective means to limit oxidative stress and to confer neuroprotection in PD. In this respect, the inducible flavoprotein NAD(P)H:quinone oxidoreductase (NQO1) is of particular interest as it is directly implicated in the detoxication of DA-quinones and, in addition, has broad spectrum anti-oxidant properties. To study the potential pathophysiological role of NQO1 in PD, the cellular expression of NQO1 was examined in the mesencephalon of PD patients and age-matched controls. In the substantia nigra pars compacta (SNpc), NQO1 was found to be expressed in astroglial and endothelial cells and, albeit less frequently, also in dopaminergic neurons. Moreover, while overt NQO1 immunoreactivity was absent in the surrounding nervous tissue, in the Parkinsonian SNpc a marked increase in the astroglial and neuronal expression of NQO1 was consistently observed. 相似文献
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Background
Correct diagnosis in psychiatry may be improved by novel diagnostic procedures. Computerized Decision Support Systems (CDSS) are suggested to be able to improve diagnostic procedures, but some studies indicate possible problems. Therefore, it could be important to investigate CDSS systems with regard to their feasibility to improve diagnostic procedures as well as to save time. 相似文献7.
The synthesis of viral plus-strand and minus-strand RNAs in cowpea protoplasts inoculated with mixtures of alfalfa mosaic virus nucleoproteins (B, M, Tb, and Ta) was analyzed by the Northern blotting technique. A mixture of B, M, and Tb induced the synthesis of plus-strand RNAs 1, 2, 3, and 4 and three minus-strand RNAs corresponding to RNAs 1, 2, and 3, respectively. Compared to this complete infection, a mixture of B and M induced the synthesis of a reduced amount of plus-strand RNAs 1 and 2 and a greatly enhanced amount of minus-strand RNAs 1 and 2. No detectable viral RNA synthesis was induced by mixtures of B and Tb or M and Tb. It is concluded that expression of genomic RNAs 1 and 2 results in the formation of a replicase activity that produces roughly equal amounts of viral plus- and minus-strand RNAs and that an RNA 3-encoded product, possibly the coat protein, is responsible for a switch to an asymmetric production of viral plus-strand RNA. The observation that no minus-strand corresponding to the subgenomic RNA 4 is produced suggests that recognition of the genome segments by the viral replicase involves sequences outside the 3'-terminal regions that are homologous to RNA 4. 相似文献
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M. Taboada A. Baluja S.H. Park P. Otero C. Gude A. Bolón E. Ferreiroa A. Tubio A. Cariñena V. Caruezo J. Alvarez P.G. Atanassoff 《Revista espa?ola de anestesiología y reanimación》2021,68(7):384-391
Background of the studyThe goal of the study was to compare the incidence of complications, technical difficulty of intubation and physiologic pre-intubation status between the first intubation and reintubation performed on the same patient in an ICU.Materials and methodsThe study was approved by the ethics committee of Galicia (Santiago-Lugo, code No. 2015-012). Due to the observational, noninterventional, and noninvasive design of this study, the need for written consent was waived by the ethics committee of Galicia. Patients requiring tracheal intubation and reintubation in the ICU were included in this prospective observational study. Main endpoint was to compare the incidence of complications, physiologic pre-intubation status, and the rate of technical difficulty of intubation between the first intubation and reintubation performed on the same patient in an ICU.Results and discussion504 patients were intubated in our ICU during the study period, and 82 (16%) required reintubation. There was no difference between the first intubation and reintubation regarding number of total complication (35% vs 33%; P = .86), hypotension (24% vs 24%; P = 1), hypoxia (26% vs 26%; P = 1), esophageal intubation (1% vs 1%; P = 1), and bronchoaspiration (2% vs 1%; P = .86). Physiologic pre-intubation status and technical difficulty of intubation did not differ between the first intubation and reintubation.ConclusionsIn our ICU patients requiring tracheal reintubation, incidence of complications, physiologic pre-intubation status, and technical difficulty of intubation did not differ between the first intubation and reintubation. 相似文献
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Cystic hypersecretory carcinoma (CHC) is a rare variant of intraductal carcinoma. A CHC in a 50-year-old woman was excised and processed for light and electron microscopy and immunohistochemistry. The tumor had a marked cystic appearance. The walls of the cysts consisted of epithelial and myoepithelial cells and a well-developed basement membrane. The epithelial cells contained well-developed rough-surfaced endoplasmatic reticulum and Golgi apparatus. Secretory granules were not detected, with the exception of a few mucus-producing cells. The secretion was predominantly homogenous, reminiscent of thyroid colloid, and demonstrated distinct PAS positivity. The cells displayed a strong labeling with epithelial membrane antigen (EMA) and EMA-positive structures were observed within the intraluminal secretion, too. Some of these were stained by alcian blue. In addition, the colloid-like material was admixed with mucus showing a filamentous internal structure and lipid droplets resulting in some heterogenity of the secretion. Intraductal micropapillary proliferation in some of the cysts and adjacent nondistended ducts was a further defining feature of the tumor. Steroid hormone receptor and Ki-67 proliferation marker immuno his Tochemistry showed scattered positivity among the tumor cells. These results are in agreement with previous observations and further clarify the nature of this low-grade in situ cancer. 相似文献