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991.
Blood lead concentrations and body iron status were investigated in 279 children. Blood lead concentrations showed no increase during iron depletion phase (stage I) but markedly increased from the phase of iron deficient erythropoiesis (stage II). Increased blood lead concentrations in anaemic subjects significantly decreased after iron supplementation.  相似文献   
992.
Cho JY  Kim SH  Lee SE 《European urology》2000,37(4):443-448
OBJECTIVE: To assess the usefulness of color and power Doppler ultrasound in predicting the benignity and malignancy of the peripheral hypoechoic lesion of the prostate. METHODS: Thirty-nine patients who had peripheral hypoechoic lesions on transrectal ultrasound were evaluated with color and power Doppler ultrasound followed by lesion-specific transrectal ultrasound-guided biopsies. The interpretation of color and power Doppler ultrasound was not performed separately and flow signals were categorized using a combination of the two modalities. The amount of flow signals within the lesion was evaluated and categorized into three groups: increased/equal/decreased flow compared to surrounding normal tissue on ultrasound. Doppler spectra could be obtained from the lesions in 23 patients. The amount of flow signals and resistive indexes of the spectra of the lesions were compared with those of surrounding normal tissue using the Mann-Whithney U test. RESULTS: Transrectal ultrasound-guided biopsy of the hypoechoic lesions revealed prostate cancer in 20 patients and benign prostatic diseases in 19. Flow signals within the lesions were of increased/equal/decreased flow compared to surrounding normal tissue in 16/2/2 in the prostate cancer group and 3/9/7 in the benign disease group, respectively. The difference was statistically significant (p = 0.0003). Resistive indexes of the lesion were 0.58-1.0 (mean 0.75) in the prostate cancer group and 0.57-1.0 (mean 0.80) in the benign disease group, and there was no significant difference between the two groups (p = 0.82). If we consider an increased flow signal within a peripheral hypoechoic lesion as a sign of prostate cancer, color power Doppler ultrasound has a sensitivity of 80%, a specificity of 84%, and an accuracy of 82%. CONCLUSION: Evaluation of peripheral hypoechoic lesions of the prostate with color and power Doppler may enhance the diagnostic capability of transrectal ultrasound.  相似文献   
993.
994.
It has been suggested that transient osteoporosis or the bone marrow oedema syndrome (BMOS) may be the initial phase of osteonecrosis of the femoral head (ONFH) and that there may be a common pathophysiology. In this study, we have assessed the MR images of 200 consecutive patients with ONFH in respect of the BMO pattern in order to test this hypothesis. This pattern was not observed in the early stage of ONFH. The initial abnormal finding detected on the MR images was an abnormal band of intensity at the junction between the necrotic area and the normal bone. Structural damage of the head seems to result in the appearance of the BMO pattern and the development of pain in ONFH. There was no finding to support the existence of a continuum between BMOS and ONFH.  相似文献   
995.
The association of hyperglycemia and markers of hepatic dysfunction with dextrose infusion rates in Korean patients receiving total parenteral nutrition (TPN) was studied. A retrospective study of 122 patients with normal glucose levels and liver function tests (LFTs) was conducted. Pharmacy and medical records of all patients who received TPN from three university-affiliated teaching hospitals in Korea between January 1998 and December 1999 were reviewed. Each patient was categorized as receiving dextrose at (1) < or = 5 or > 5 mg/kg/min and (2) < or = 4, 4.1-5, 5.1-6, or > 6 mg/kg/min. Fifty-five patients received dextrose at a rate of > 5 mg/kg/min for 15.1 +/- 12.8 days and 67 patients at a rate of < or = 5 mg/kg/min for 10.1 +/- 6.8 days. Two patients in each group did not have follow-up glucose levels. Of the 53 patients in the > 5 mg/kg/min group, 16 exhibited hyperglycemia, compared with 21 of the 65 receiving lower rates of dextrose infusion. Elevated aspartate transaminase was the most common abnormal LFT value in both groups (25% and 29% in the < or = 5- and > 5-mg/kg/min groups, respectively). In the group receiving dextrose at > 5 mg/kg/min, 22.2% had two hepatic enzyme levels elevated concurrently, while 18.5% had two hepatic enzyme levels elevated in the group receiving dextrose at < or = 5 mg/kg/min. Regression analysis revealed that duration of TPN and dextrose infusion rate were positively correlated with blood glucose levels and that duration of TPN was positively correlated with abnormal LFT values. A retrospective study of Korean patients revealed no significant difference in the risk of hyperglycemia or hepatic dysfunction between those receiving < or = 5 and > 5 mg/kg/min dextrose infusion in their TPN.  相似文献   
996.
Vitamin H (biotin) was incorporated into a hydrophobically modified polysaccharide, pullulan acetate (PA), in order to improve the cancer-targeting activity and internalization of self-assembled nanoparticles. The biotinylated pullulan acetate (BPA) nanoparticles were prepared by a diafiltration method and the mean diameter was approximately 100 nm. Three samples of biotinylated pullulan acetate (BPA), comprising 7 (BPA 1), 20 (BPA 2), and 39 (BPA 3) vitamin H groups per 100 anhydroglucose units of PA, were synthesized. The critical aggregation concentrations (CAC) of the BPA nanoparticles in distilled water were 3.1 x 10(-3), 4.3 x 10(-3) and 6.8 x 10(-3) mg/ml for BPA 1, BPA 2, and BPA 3, respectively. Adriamycin (ADR) was loaded into the BPA nanoparticles as a model drug. The loading efficiencies and ADR content in the BPA nanoparticles decreased with increasing vitamin H content due to a lower hydrophobicity. The RITC-labeled BPA nanoparticles exhibited very strong adsorption to the HepG2 cells, while the RITC-labeled PA nanoparticles did not show any significant interaction. The degree of the interaction increased with increasing vitamin H content. Confocal laser microscopy also revealed that internalization of the BPA nanoparticles into the cancer cells depended on the vitamin H content.  相似文献   
997.
The purpose of the present study was to evaluate the effect of 1,7-phenanthroline (PH), which has been proposed to be a selective phase II enzyme inducer, on the gene expression of xenobiotic transporters, as well as hepatic and renal drug-metabolizing enzymes. After oral administration of PH for 3 days to male Sprague-Dawley rats, mRNA levels in liver (75 and 150 mg/kg doses) and kidney (75 mg/kg dose only) were determined using real-time quantitative polymerase chain reaction. At 150 mg/kg/day, PH treatment resulted in significant increases in hepatic mRNA levels of Mrp3 (36-fold), UGT1A6 (20-fold), UGT2B1 (4-fold), and quinone reductase (QR, 5-fold), compared with the vehicle-treated group. Similar increases in Mrp3 (99-fold), UGT1A6 (17-fold), UGT2B1 (3-fold), and QR (11-fold) mRNA levels were observed in the liver after PH treatment of rats at 75 mg/kg/day. In contrast, the expression levels of CYP2C11 and Oatp2 were decreased by approximately 80 and 50%, respectively. In addition, PH (75 mg/kg/day) elicited statistically significant changes in renal gene expression of CYP3A1, UGT1A6, QR, and Mrp3, but the magnitude of renal Mrp3 induction was less than 2-fold over control. Although PH is known to modulate hepatic glucuronidation in vivo, these data indicated that PH induced mRNA levels of the efflux transporter, Mrp3, which may also affect the disposition of xenobiotics.  相似文献   
998.
Hirsch J  Ruge MI  Kim KH  Correa DD  Victor JD  Relkin NR  Labar DR  Krol G  Bilsky MH  Souweidane MM  DeAngelis LM  Gutin PH 《Neurosurgery》2000,47(3):711-21; discussion 721-2
OBJECTIVE: To evaluate an integrated battery of preoperative functional magnetic resonance imaging (fMRI) tasks developed to identify cortical areas associated with tactile, motor, language, and visual functions. METHODS: Sensitivity of each task was determined by the probability that a targeted region was activated for both healthy volunteers (n = 63) and surgical patients with lesions in these critical areas (n = 125). Accuracy of each task was determined by the correspondence between the fMRI maps and intraoperative electrophysiological measurements, including somatosensory evoked potentials (n = 16), direct cortical stimulation (n = 9), and language mapping (n = 5), and by preoperative Wada tests (n = 13) and visual field examinations (n = 6). RESULTS: For healthy volunteers, the overall sensitivity was 100% for identification of the central sulcus, visual cortex, and putative Wernicke's area, and 93% for the putative Broca's area (dominant hemisphere). For patients with tumors affecting these regions of interest, task sensitivity was 97% for identification of the central sulcus, 100% for the visual cortex, 91% for the putative Wernicke's area, and 77% for the putative Broca's area. These sensitivities were enhanced by the use of multiple tasks to target related functions. Concordance of the fMRI maps and intraoperative electrophysiological measurements was observed whenever both techniques yielded maps and Wada and visual field examinations were consistent with fMRI results. CONCLUSION: This integrated fMRI task battery offers standardized and noninvasive preoperative maps of multiple critical functions to facilitate assessment of surgical risk, planning of surgical routes, and direction of conventional, intraoperative electrophysiological procedures. Thus, a greater range of structural and functional relationships is brought to bear in the service of optimal outcomes for neurosurgery.  相似文献   
999.
INTRODUCTION: Immune privilege provides a natural paradigm for potentially down-regulating allogeneic and xenogeneic inflammatory immune responses. Fas ligand has been suggested as a general underlying mechanism of immune privilege; the human Fas ligand has been shown to ligate murine Fas in vitro. METHODS: In this study, we examined whether the human testicular xenograft, a presumed immune-privileged tissue would have prolonged survival in mice. In addition, in vitro and in vivo murine xenogeneic immune responses to the human testicular xenografts were characterized using MHC class I, MHC class II, CD4, CD8, CD4/8 knockout mice. RESULTS: Unlike in rodent testis, Fas ligand mRNA is not expressed and Fas is highly expressed in human testis. Human testicular xenografts are immunogenic, and do not induce any preferential pattern of recipient systemic Th1 or Th2 cytokine bias. Interestingly, an indefinite survival of the human testicular xenografts is observed in murine MHC class II knockout mice, whereas the human skin xenografts were rejected without a delay. In vivo murine immune responses to human testicular xenografts require a recipient MHC class II-dependent CD4 T cell-mediated process that appears to depend on B7-1/B7-2 costimulatory signals. CONCLUSIONS: Our results demonstrate that the concept of immune privilege, as defined by the expression of Fas ligand and prolonged survival after transplantation, cannot be extended to human testis. The stringent restriction of murine xenogeneic immune responses to discordant human testicular xenografts to the indirect MHC class II-dependent CD4 T cell-mediated pathway suggests a potential venue for immune modulation to induce tolerance across a discordant species barrier.  相似文献   
1000.
PURPOSE: Flavopiridol is a cyclin-dependent kinase inhibitor with preclinical activity against prostate cancer cell lines. A Phase II trial was conducted to determine the activity of flavopiridol in patients with metastatic hormone-refractory prostate cancer. EXPERIMENTAL DESIGN: A total of 36 patients was enrolled from several institutions and treated with a 72-h continuous infusion of flavopiridol every 14 days at the eventual starting dose of 40 mg/m(2)/day. Dose escalation up to 60 mg/m(2)/day was permitted if no significant toxicity was observed. Responses were assessed every 12 weeks. Only those patients completing four courses of the 72-h infusion were considered evaluable for response because the primary objective was to determine progression-free survival at 6 months given the cytostatic nature of the agent. RESULTS: This study was conducted in a two-stage fashion. During the first stage, at least 20 evaluable patients needed to be enrolled to assess response. There were 22 of 36 patients evaluable for response. No objective responses were observed. Only 4 patients had stable disease for 16, 26, 29, and 48 weeks, respectively, stopping the trial by design as only 3 of 22 (14%) of the patients met the 6-month progression-free survival end point. The most common toxicities were diarrhea (grade 1 and 2) and nausea, although some grade 3 and 4 diarrhea (11 and 6%, respectively) were evident. CONCLUSIONS: Flavopiridol has disappointing single-agent activity in hormone-refractory prostate cancer when administered at this dose and schedule. Its use in prostate cancer should be reserved for evaluation in combination therapies or alternative schedules.  相似文献   
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