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2.
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
3.
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4.
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
5.
BACKGROUND:
Flavonoids are polyphenolic substances with antioxidant properties, and they are found in different vegetables and fruits. Epidemiological studies have shown that the consumption of flavonoids reduces the prevalence of cardiovascular diseases. The use of synthetic antioxidants, however, has been limited because of their toxicity. Therefore, medical researchers have intensified their quest to find natural antioxidants.OBJECTIVES:
To investigate the effect of several pure flavonoids, such as kaempferol, quercetin, morin and rutin, on red blood cell hemolysis and evaluate their -SH capacity as an indicator of membrane protection.METHODS:
The rate of hemolysis and cell membrane -SH capacity were determined by spectrophotometry. Red blood cell peroxidation was induced using 2,2′-azo-bis-(2-amidinopropane) dihydrochloride. The effect of each flavonoid on hemolysis was examined at three concentrations (0.5 μg/mL, 5 μg/mL and 10 μg/mL), however, only the greatest concentration (10 μg/mL) of each flavonoid was used to study the effect on -SH groups.RESULTS:
In all cases, the antioxidant activity was dose-dependent. Rutin showed the highest inhibitory effect on hemolysis among flavonoids (42.5%). The protective effect of kaempferol, rutin and morin against -SH group oxidation measured 7.7%, 23.3% and 26.4%, respectively.CONCLUSIONS:
Results showed that flavonoids and flavonoid-containing plants can be used as natural antioxidants for the treatment and prevention of disease conditions, the pathogenesis of which is mediated by lipid peroxidation. 相似文献6.
7.
Hugo C. van der Veen Hans-Peter W. van Jonbergen Rudolf W. Poolman Sjoerd K. Bulstra Jos J. A. M. van Raay 《International orthopaedics》2013,37(1):9-14
Joint arthroplasty registries show an increased rate of aseptic loosening in uncemented acetabular components as compared to cemented acetabular components. Since loosening is associated with particulate wear debris, we postulated that uncemented acetabular components demonstrate a higher polyethylene wear rate than cemented acetabular components in total hip arthroplasty. We performed a systematic review of the peer-reviewed literature, comparing the wear rate in uncemented and cemented acetabular components in total hip arthroplasty. Studies were identified using MEDLINE (PubMed), EMBASE and the Cochrane Central Register of Controlled Trials. Study quality was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. The search resulted in 425 papers. After excluding duplicates and selection based on title and abstracts, nine studies were found eligible for further analysis: two randomised controlled trials, and seven observational studies. One randomised controlled trial found a higher polyethylene wear rate in uncemented acetabular components, while the other found no differences. Three out of seven observational studies showed a higher polyethylene wear in uncemented acetabular component fixation; the other four studies did not show any differences in wear rates. The available evidence suggests that a higher annual wear rate may be encountered in uncemented acetabular components as compared to cemented components. 相似文献
8.
Stevens M Wagenmakers R Groothoff JW Bulstra SK van den Akker-Scheek I Zijlstra W 《Patient education and counseling》2007,69(1-3):196-199
OBJECTIVE: To determine to what extent aspects of patient characteristics (age, gender, family status, education and comorbidity) are predictive for the level of physical activity of persons with a total hip arthroplasty (THA). METHODS: A cross-sectional study including 372 patients. Demographics, comorbidity and physical activity behavior were assessed by means of a questionnaire and from medical records. Linear regression analysis was used to determine to what extent patient characteristics are predictive of level of physical activity. Binary logistic regression modeling was used to determine the extent to which patient characteristics are predictive in meeting international guidelines on health-enhancing physical activity. RESULTS: Age, education and family status significantly predict level of physical activity (R(2)=0.19). Only gender significantly predicts meeting international guidelines on health-enhancing physical activity (OR=2.06, 95% CI 1.20-3.54). CONCLUSION: Patients at risk can be identified by means of patient characteristics. Increasing age, lower education and living alone are associated with a physically inactive lifestyle. PRACTICE IMPLICATIONS: Health care workers involved in the treatment of THA patients should lay an emphasis on the beneficial aspects of physical activity. 相似文献
9.
van den Akker-Scheek I Zijlstra W Groothoff JW van Horn JR Bulstra SK Stevens M 《Patient education and counseling》2007,65(2):171-179
OBJECTIVE: Validation of the program theory of the Groningen orthopaedic exit strategy (GOES), a theory-driven program aiming to improve the rehabilitation of total hip and knee arthroplasty patients after shortened hospital stay. First part of the program theory is the action theory, hypothesising that the GOES treatment positively influences the mediating variables (self-efficacy, social support, pain-coping). The second part, the conceptual theory, hypothesis a positive relationship between these variables and the outcome variables (ADL functioning, physical activity behaviour, quality of life). METHODS: Patients were randomly assigned to the GOES or control groups. Questionnaires were used to assess mediating and outcome variables in 103 patients (50 GOES, 53 controls) pre-operatively, and 6 and 26 weeks post-operatively. RESULTS: No difference was seen between the two groups in terms of changes between pre-operative and post-operative mediating variables (action theory). Moderate-to-large correlations explaining reasonable amount of variance (22%, 25%, 56%) were found between the mediating and outcome variables (conceptual theory). CONCLUSION: The conceptual theory is supported; however, as the treatment did not influence the mediating variables (action theory), it has no added value in its current form. PRACTICE IMPLICATIONS: The treatment needs to be adjusted; it is discussed that individualised treatment could be more effective. 相似文献
10.
van den Akker-Scheek I Stevens M Bulstra SK Groothoff JW van Horn JR Zijlstra W 《Archives of physical medicine and rehabilitation》2007,88(3):361-367
OBJECTIVE: To describe recovery of gait after total hip arthroplasty (THA) based on the assessment of spatiotemporal gait parameters determined with an ambulatory system. DESIGN: A 6-month inception cohort study. SETTING: Inpatient and outpatient setting in an academic hospital. PARTICIPANTS: Sixty-three patients participating in a short-stay program for THA. INTERVENTION: Primary unilateral THA. MAIN OUTCOME MEASURES: Walking speed, step length, step duration, and variability coefficient assessed at different walking speeds while performing an additional cognitive task and an endurance test. All measures were obtained preoperatively and 6 weeks and 6 months postoperatively. RESULTS: Patients improved significantly over time; however, extent and speed of recovery of gait parameters differed for each test part. The relation between walking speed and step length showed systematic improvement when analyzed over a range of speeds. At 6 months, the variability coefficient of the additional task test part was comparable with the preferred walking variability coefficient. The endurance test results could be predicted from the results of preferred walking. CONCLUSIONS: Assessment of recovery of gait function requires more than only assessment of "normal" walking. Particularly, an analysis of walking at different speeds and walking while performing an additional cognitive task demonstrate different aspects of gait recovery after THA. 相似文献