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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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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5.
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
6.
Gamal H. Eltabbakh M.D. M.Steven Piver M.D. Ronald E. Hempling M.D. Fernando O. Recio M.D. Shashikant B. Lele M.D. David L. Marchetti M.D. Trudy R. Baker M.D. Leslie E. Blumenson Ph.D. 《Gynecologic oncology》1998,70(3):392-397
Objective.The extreme drug resistance (EDR) assay has been correlated with failure of response to chemotherapy in greater than 99% of patients. The goal of this study is to correlate the results of the EDR assay to response to first-line paclitaxel/cisplatin among patients with epithelial ovarian cancer.Methods.Seventy-five of 100 patients with epithelial ovarian cancer for whom EDR assay was performed were treated with weekly induction cisplatin (1 mg/kg body wt) × 4, followed by monthly paclitaxel (135 mg/m2) and cisplatin (75 mg/m2) × 6 and were evaluable for correlation of response to chemotherapy and EDR assay. Specimens for EDR assay were obtained at primary surgery and the EDR assay was performed by Oncotech, Inc. Response to chemotherapy was correlated to EDR assay results regarding paclitaxel and cisplatin.Results.Among 75 evaluable patients, the prevalence of EDR to paclitaxel was 20.0% (n= 15) and to cisplatin it was 2.7% (n= 2). Only 1 patient (1.3%) exhibited EDR to both paclitaxel and cisplatin. Surgical assessment of response was performed in 42 patients; 33 patients were clinically evaluable. The overall response rate was 85.3%. The overall response rate for patients whose tumors demonstrated no EDR to either paclitaxel or cisplatin did not differ significantly from that for patients whose tumors demonstrated EDR to at least one of these two drugs (86.4% versus 81.3%, respectively,P= 0.692). Similarly, the complete surgical response rate for both groups did not differ significantly (25.4% versus 12.5%, respectively,P= 0.34). A single patient whose tumor exhibited EDR to both paclitaxel and cisplatin had tumor progression. The sensitivity, specificity, positive predictive value, and negative predictive value of the EDR assay were 79.6, 27.0, 86.0, and 19.0%, respectively.Conclusions.EDR to paclitaxel does not preclude response to the combination of paclitaxel and cisplatin as primary therapy for patients with epithelial ovarian cancer. The role of the EDR assay in the primary management of patients with epithelial ovarian cancer remains to be determined. 相似文献
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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9.
Unique situation of hepatocellular carcinoma in Egypt: A review of epidemiology and control measures
Reem Ezzat Mohamed Eltabbakh Mohamed El Kassas 《World journal of gastrointestinal oncology》2021,13(12):1919-1938
Hepatocellular carcinoma (HCC) is the sixth most common primary malignancy worldwide, and the third most common cause of death among cancers world wide. HCC occurs in several pre-existing conditions, including hepatitis C, hepatitis B virus, and non-alcoholic cirrhosis. Egypt used to be the country with the heaviest hepatitis C virus (HCV) burden. The relationship between HCV and HCC is an important research area. In Egypt, HCC is a significant public health problem. A possible cause for the increasing rates of detection of HCC in Egypt is the mass screening program that was carried by the government for detecting and treating HCV. A multidisciplinary approach is now widely applied to HCC management in health centers all over Egypt. Different treatment modalities are available in Egypt, with success rates comparable to global rates. The Egyptian health authorities have made the elimination of HCV from Egypt a special priority, and this approach should lead to a decrease in number of HCC cases in the near future. In this article we review the current situation of HCC in Egypt, including epidemiological aspects, relevant risk factors for HCC development, strategies, and efforts established by health authorities for the screening and prevention of both HCV and HCC in Egypt. We highlight the different modalities for HCC treatment. 相似文献
10.
Women with ovarian cancer have poor overall survival rates, largely because the disease is so often diagnosed at an advanced, less curable stage. Because women with early ovarian cancer experience good survival rates, there is great interest in the study and detection of early disease. Familial ovarian cancer has been relevant to the study of early ovarian cancer in two different ways. First, women from ovarian cancer families often undergo prophylactic oophorectomy to prevent development of this disease. These ovaries have been studied for pathologic or molecular features that might represent early preinvasive disease. Second, screening tests to detect presymptomatic ovarian cancer have selectively targeted this population because of the increased positive predictive value of these tests in this population. A review of the clinical, pathologic, epidemiologic, and molecular biologic aspects of familial ovarian cancer provides a background to facilitate understanding these issues. 相似文献