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81.
Grases F Costa-Bauzá A Königsberger E Königsberger LC 《International urology and nephrology》2000,32(1):19-27
Calcium renal lithiasis formation depends on the balance between thermodynamic (supersaturation) and kinetic (inhibitors,
nucleants)factors. In this paper, the importance of both groups was evaluated using(a) the complete urine analysis data obtained
from 32 healthy volunteers and 141 active stone-formers, and (b) a comprehensive computer model to calculate the supersaturation
values of calcium oxalate monohydrate,hydroxyapatite and brushite in each urine sample. The results of this evaluation were
used to assess the possible effectiveness of a given pharmacological treatment.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
82.
Circulating growth factor levels are associated with tumorigenesis in neurofibromatosis type 1. 总被引:2,自引:0,他引:2
George A Mashour Pablo Hernáiz Driever Melanie Hartmann Stephanie N Drissel Tingguo Zhang Bianca Scharf Ursula Felderhoff-Müser Sadatoshi Sakuma Reinhard E Friedrich Robert L Martuza Victor Felix Mautner Andreas Kurtz 《Clinical cancer research》2004,10(17):5677-5683
PURPOSE: Neurofibromatosis type 1 (NF1) is characterized by systemic development of neurofibromas. Early clinical diagnosis can be ambiguous, and genetic diagnosis can be prohibitively difficult. Dysregulation of a number of growth factors has been suggested to be a mechanism of pathogenesis. This study was performed to assess the contribution of circulating growth factors for diffuse tumorigenesis and the diagnostic value of circulating growth factor identification in serum. EXPERIMENTAL DESIGN: The growth stimulation of neurofibroma-derived cells by serum from NF1 patients was tested, and serum growth factor levels in a cohort of NF1 patients (n = 39) between the ages of 7 and 70 years were analyzed. RESULTS: Concentrations of midkine (MK) and stem cell factor, but not epidermal growth factor, were substantially increased in serum of NF1 patients when compared with healthy controls. Within the NF1 group, MK levels increased dramatically at puberty from an average of 0.79 ng/mL in patients <18 years to 1.18 ng/mL in patients >18 years old. Stem cell factor and MK concentrations above a defined threshold in serum of NF1 patients are of diagnostic benefit for 96% of patients in the cohort tested. Furthermore, serum from NF1 patients enhanced proliferation of human neurofibroma-derived primary Schwann cells and endothelial cells substantially better than normal serum. CONCLUSIONS: Enhanced circulating growth factor levels contribute to diffuse tumorigenesis in NF1 and may provide the basis for molecular diagnosis. 相似文献
83.
The relationship of serum-eosinophil cationic protein and eosinophil count to disease activity in children with bronchial asthma 总被引:1,自引:0,他引:1
84.
85.
Marie A McAnuff Wayne W Harding Felix O Omoruyi Helen Jacobs Errol Y Morrison Helen N Asemota 《Food and chemical toxicology》2005,43(11):1667-1672
In this study, three steroidal sapogenins (Delta3 diosgenin, diosgenin, and pennogenin) and the phytosterols, stigmasterol and beta-sitosterol were isolated from Jamaican bitter yam, Dioscorea polygonoides. Their effects on fasting blood glucose and intestinal amylase and ATPases in streptozotocin-induced diabetic rats were studied. The diabetic rats (fed supplemented and unsupplemented diets) lost weight significantly compared to the normal group. There was a significant increase in the activity of alpha-amylase in the proximal region of the small intestinal mucosa of diabetic rats fed sapogenin extract or commercial diosgenin. However, this did not result in increased fasting blood glucose. Instead, supplementation of the diet with bitter yam sapogenin extract significantly decreased fasting blood glucose compared to the diabetic group. Supplementation of the diet with bitter yam sapogenin extract or commercial diosgenin significantly reduced Na+-K+-ATPase activity in all three regions compared to the diabetic control group. Commercial diosgenin supplementation resulted in a significant increase in Ca2+ ATPase activity in proximal region compared to the diabetic control and bitter yam sapogenin extract groups. The effect of bitter yam sapogenin extract or commercial diosgenin on intestinal Na+-K+-ATPase activity could account for their hypoglycemic properties. However, there was adverse effect on the body weight. 相似文献
86.
Hans-Peter Gschwind Ulrike Pfaar Felix Waldmeier Markus Zollinger Claudia Sayer Peter Zbinden Michael Hayes Rolf Pokorny Michael Seiberling Monique Ben-Am Bin Peng Gerhard Gross 《Drug metabolism and disposition》2005,33(10):1503-1512
Imatinib mesylate (GLEEVEC, GLIVEC, formerly STI571) has demonstrated unprecedented efficacy as first-line therapy for treatment for all phases of chronic myelogenous leukemia and metastatic and unresectable malignant gastrointestinal stromal tumors. Disposition and biotransformation of imatinib were studied in four male healthy volunteers after a single oral dose of 239 mg of (14)C-labeled imatinib mesylate. Biological fluids were analyzed for total radioactivity, imatinib, and its main metabolite CGP74588. Metabolite patterns were determined by radio-high-performance liquid chromatography with off-line microplate solid scintillation counting and characterized by liquid chromatography-mass spectrometry. Imatinib treatment was well tolerated without serious adverse events. Absorption was rapid (t(max) 1-2 h) and complete with imatinib as the major radioactive compound in plasma. Maximum plasma concentrations were 0.921 +/- 0.095 mug/ml (mean +/- S.D., n = 4) for imatinib and 0.115 +/- 0.026 mug/ml for the pharmacologically active N-desmethyl metabolite (CGP74588). Mean plasma terminal elimination half-lives were 13.5 +/- 0.9 h for imatinib, 20.6 +/- 1.7 h for CGP74588, and 57.3 +/- 12.5 h for (14)C radioactivity. Imatinib was predominantly cleared through oxidative metabolism. Approximately 65 and 9% of total systemic exposure [AUC(0-24 h) (area under the concentration time curve) of radioactivity] corresponded to imatinib and CGP74588, respectively. The remaining proportion corresponded mainly to oxidized derivatives of imatinib and CGP74588. Imatinib and its metabolites were excreted predominantly via the biliary-fecal route. Excretion of radioactivity was slow with a mean radiocarbon recovery of 80% within 7 days (67% in feces, 13% in urine). Approximately 28 and 13% of the dose in the excreta corresponded to imatinib and CGP74588, respectively. 相似文献
87.
Logan G Spector Yang Xie Leslie L Robison Nyla A Heerema Joanne M Hilden Beverly Lange Carolyn A Felix Stella M Davies Joanne Slavin John D Potter Cindy K Blair Gregory H Reaman Julie A Ross 《Cancer epidemiology, biomarkers & prevention》2005,14(3):651-655
BACKGROUND: The MLL 11q23 translocation arises in utero and is present in 75% of infant leukemias. That MLL+ acute myeloid leukemia (AML) can arise following chemotherapy with DNA topoisomerase II (DNAt2) inhibitors suggests that these substances, which also occur naturally in foods, may contribute toward infant leukemia. We hypothesized that maternal consumption of dietary DNAt2 inhibitors during pregnancy would increase the risk of infant leukemia, particularly AML(MLL+). METHODS: This Children's Oncology Group case-control study consisted of 240 incident cases of infant acute leukemia [AML and acute lymphoblastic leukemia (ALL)] diagnosed during 1996 to 2002 and 255 random digit dialed controls. Maternal diet during pregnancy was determined through a food frequency questionnaire. An index of specific foods identified a priori to contain DNAt2 inhibitors as well as vegetables and fruits were created and analyzed using unconditional logistic regression. RESULTS: There was little evidence of an association between the specific DNAt2 index and leukemia overall and by subtype. An exception was AML(MLL+); odds ratios (95% confidence intervals) comparing the second to fourth quartiles to the first were 1.9 (0.5-7.0), 2.1 (0.6-7.7), and 3.2 (0.9-11.9), respectively (P for trend = 0.10). For the vegetable and fruit index, there were significant or near-significant inverse linear trends for all leukemias combined, ALL(MLL+), and AML(MLL-). CONCLUSION: Overall, maternal consumption of fresh vegetables and fruits during pregnancy was associated with a decreased risk of infant leukemia, particularly MLL+. However, for AML(MLL+) cases, maternal consumption of specific DNAt2 inhibitors seemed to increase risk. Although based on small numbers, these data provide some support for distinct etiologic pathways in infant leukemia. 相似文献
88.
Thierry M Muanza Ana P Cotrim Mathew McAuliffe Anastasia L Sowers Bruce J Baum John A Cook Felix Feldchtein Paul Amazeen C Norman Coleman James B Mitchell 《Clinical cancer research》2005,11(14):5121-5127
PURPOSE: Optical coherence tomography (OCT) imaging was evaluated to determine if radiation-induced mucosal damage could be noninvasively monitored in real time and correlated with histopathologic findings. EXPERIMENTAL DESIGN: Female C3H mice, ages 7 to 9 weeks, four per group, were immobilized in a custom-made Lucite jig and received 0, 15, 22.5, and 25 Gy in a single fraction to their oral cavity. OCT images were acquired of proximal, middle, and distal aspects of the dorsum of the tongue on days 0, 1, 3, 5, and 7 post-irradiation. Animals were sacrificed on day 7 and samples taken for histologic evaluation. OCT images were visually examined and also quantified by image analysis and compared with histologic findings. RESULTS: Tongues removed 7 days post-irradiation showed no visible damage; however, upon staining with toluidine blue, ulcers at the base of the tongue became visible (100% for 25 Gy, 75% after 22.5 Gy, and 0% after 15 Gy). Visual inspection of OCT images qualitatively compared with histologic findings and quantitative image analysis of the OCT images (effective light penetration depth) revealed significant changes 7 days post-irradiation compared with unirradiated controls for the base of the tongue. CONCLUSIONS: OCT allows for direct noninvasive real-time acquisition of digitally archivable images of oral mucosa and can detect radiation-induced changes in the mucosa before visual manifestation. OCT may be a useful technique to quantify subclinical radiation-induced mucosal injury in experimental chemoradiation clinical trials. 相似文献
89.
Endometrial carcinoma recurrence according to race and ethnicity: An NRG Oncology/Gynecologic Oncology Group 210 Study 下载免费PDF全文
A.S. Felix T.M. Brasky D.E. Cohn D.G. Mutch W.T. Creasman P.H. Thaker J.L. Walker R.G. Moore S.B. Lele S.R. Guntupalli L.S. Downs Ci Nagel J.F. Boggess M.L. Pearl O.B. Ioffe W. Deng D.S. Miller L.A. Brinton 《International journal of cancer. Journal international du cancer》2018,142(6):1102-1115
Non‐Hispanic black (NHB) women are more likely to experience an endometrial carcinoma (EC) recurrence compared to non‐Hispanic white (NHW) women. The extent to which tumor characteristics, socioeconomic status (SES) and treatment contribute to this observation is not well defined. In the NRG Oncology/Gynecology Oncology Group (GOG) 210 Study we evaluated associations between race/ethnicity and EC recurrence according to tumor characteristics with adjustment for potential confounders. Our analysis included 3,199 NHW, 532 NHB and 232 Hispanic women with EC. Recurrence was documented during follow‐up. We used Cox regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between race/ethnicity and EC recurrence in models stratified by histologic subtype (low‐grade endometrioid, high‐grade endometrioid, serous, mixed cell, carcinosarcoma, clear cell) or stage (I, II, III) and adjusted for age, SES, body mass index, smoking status and treatment. In histologic subtype‐stratified models, higher EC recurrence was noted in NHB women with low‐grade endometrioid (HR = 1.94, 95% CI = 1.21–3.10) or carcinosarcomas (HR = 1.66, 95% CI = 0.99–2.79) compared to NHWs. In stage‐stratified models, higher EC recurrence was noted among NHB women with stage I (HR = 1.48, 95% CI = 1.06–2.05) and Hispanic women with stage III disease (HR = 1.81, 95% CI = 1.11–2.95). Our observations of higher EC recurrence risk among NHB and Hispanic women, as compared to NHW women, were not explained by tumor characteristics, SES, treatment or other confounders. Other factors, such as racial differences in tumor biology or other patient factors, should be explored as contributors to racial disparities in EC recurrence. 相似文献
90.
Kurt Schmidlin Adrian Spoerri Felix Niggli Michael Grotzer Nicolas X. von der Weid Matthias Egger Nicole Probst‐Hensch Marcel Zwahlen Claudia E. Kuehni and the Swiss Paediatric Oncology Group the Swiss National Cohort Study 《International journal of cancer. Journal international du cancer》2016,138(12):2856-2866
In this study, we investigated whether childhood cancer survival in Switzerland is influenced by socioeconomic status (SES), and if disparities vary by type of cancer and definition of SES (parental education, living condition, area‐based SES). Using Cox proportional hazards models, we analyzed 5‐year cumulative mortality in all patients registered in the Swiss Childhood Cancer Registry diagnosed 1991–2006 below 16 years. Information on SES was extracted from the Swiss census by probabilistic record linkage. The study included 1602 children (33% with leukemia, 20% with lymphoma, 22% with central nervous system (CNS) tumors); with an overall 5‐year survival of 77% (95%CI 75–79%). Higher SES, particularly parents' education, was associated with a lower 5‐year cumulative mortality. Results varied by type of cancer with no association for leukemia and particularly strong effects for CNS tumor patients, where mortality hazard ratios for the different SES indicators, comparing the highest with the lowest group, ranged from 0.48 (95%CI: 0.28–0.81) to 0.71 (95%CI: 0.44–1.15). We conclude that even in Switzerland with a high quality health care system and mandatory health insurance, socioeconomic differences in childhood cancer survival persist. Factors causing these survival differences have to be further explored, to facilitate universal access to optimal treatment and finally eliminate social inequalities in childhood cancer survival. 相似文献