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41.
Efficacy and safety of radiofrequency ablation for perivascular hepatocellular carcinoma without hepatic inflow occlusion 总被引:6,自引:0,他引:6
BACKGROUND: The role of radiofrequency ablation (RFA) for perivascular (up to 5 mm from the major intrahepatic portal vein or hepatic vein branches) hepatocellular carcinoma (HCC) is unclear because of possible incomplete tumour ablation and potential vascular damage. This study aimed to evaluate the safety and efficacy of RFA for perivascular HCC without hepatic inflow occlusion. METHODS: Between May 2001 and November 2003, RFA using an internally cooled electrode was performed on 52 patients with perivascular HCC (group 1) through open (n = 39), percutaneous (n = 9), laparoscopic (n = 2) and thoracoscopic (n = 2) approaches. Hepatic inflow occlusion was not applied during the ablation procedure. The perioperative and postoperative outcomes were compared with those of 90 patients with non-perivascular HCC (group 2) treated by RFA during the same period. RESULTS: The morbidity rate was similar between groups 1 and 2 (25 versus 28 per cent; P = 0.844). One patient in group 1 (2 per cent) and two in group 2 (2 per cent) had developed thrombosis of major intrahepatic blood vessels on follow-up computed tomography scan. There were no significant differences between groups 1 and 2 in mortality rate (2 versus 0 per cent; P = 0.366), complete ablation rate for small HCC (92 versus 98 per cent; P = 0.197), local recurrence rate (11 versus 9 per cent; P = 0.762) and overall survival (1-year: 86 versus 87 per cent; 2-year: 75 versus 75 per cent; P = 0.741). CONCLUSION: RFA without hepatic inflow occlusion is a safe and effective treatment for perivascular HCC. 相似文献
42.
Pre-operative grading of intracranial glioma. 总被引:9,自引:0,他引:9
W W Lam K W Chan W L Wong W S Poon C Metreweli 《Acta radiologica (Stockholm, Sweden : 1987)》2001,42(6):548-554
AIM: To compare the accuracy of MR-determined cerebral blood volume (CBV) maps with SPECT imaging with thallium-201 in pre-operative grading of intracranial glioma. MATERIAL AND METHODS: Nineteen patients (7 female and 12 male, mean age 46.8 years) with intracranial gliomas were examined with MR perfusion imaging pre-operatively. Sixteen of these patients were also examined with SPECT imaging with thallium-201. The tumour to contralateral white matter NI (negative integral) and tracer uptake ratios were evaluated. The ratios in high-grade and low-grade tumours were compared. RESULTS: The maximum CBV ratios of grades I and II gliomas (2.958+/-2.217) were significantly lower than the maximum CBV ratio of grades III and IV (9.484+/-4.520), p<0.001. There was no statistical difference when CBV ratios of grades I and II (p=0.381), grades II and III (p=0.229) and grades III and IV (p=0.476) gliomas were compared. Thallium SPECT imaging showed no difference in tumour uptake ratio between low-grade and high-grade gliomas (p=0.299). CONCLUSION: MR-determined NI was useful for pre-operative grading of intracranial gliomas but SPECT thallium-201 imaging was not. 相似文献
43.
Analysis of loss of heterozygosity on chromosomes 10q, 11, and 16 in medulloblastomas 总被引:2,自引:0,他引:2
OBJECT: The loss of genetic material from specific chromosome loci is a common feature in the oncogenesis of tumors and is often indicative of the presence of important tumor suppressor genes at these loci. Recent molecular genetic analyses have demonstrated frequent loss of chromosomes 10q, 11, and 16 in medulloblastomas. The aim of this study was to localize the targeted deletion regions on the three aforementioned chromosomes in medulloblastomas. METHODS: Loss of heterozygosity (LOH) was examined on chromosomes 10q, 11, and 16 in a series of 22 primary and two recurrent medulloblastomas by using polymerase chain reaction-based microsatellite analysis. The DNA extracted from the tumors and corresponding normal blood samples were amplified independently in the presence of radioactively labeled microsatellite primers, resolved by denaturing gel electrophoresis and processed for autoradiography. The DNA obtained from control blood samples that displayed allelic heterozygosity at a given microsatellite locus were considered informative. Loss of heterozygosity was inferred when the allelic signal intensity of the tumor sample was reduced by at least 40%, relative to that of the constitutional control. The LOH analysis demonstrated that deletions of chromosomes 10q, 11p, and 16q are recurrent genetic events in the development of medulloblastomas. Three subchromosomal regions of loss have been identified and are localized to the deleted in malignant brain tumors 1 [DMBT1] gene site on chromosomes 10q25, 11p13-11p15.1, and 16q24.1-24.3. CONCLUSIONS: These results indicate that DMBT1 is closely associated with the oncogenesis of medulloblastomas and highlight regions of loss on chromosomes 11p and 16q for further fine mapping and cloning of candidate tumor suppressor genes that are important for the genesis of medulloblastoma. 相似文献
44.
Correlation of serum basic fibroblast growth factor levels with clinicopathologic features and postoperative recurrence in hepatocellular carcinoma 总被引:25,自引:0,他引:25
BACKGROUND: Basic fibroblast growth factor (bFGF) is an important positive regulator of tumor angiogenesis. This study evaluated the role of serum bFGF as a biological marker of tumor invasiveness and postresection recurrence in hepatocellular carcinoma (HCC). METHODS: Concentrations of bFGF in preoperative serum samples in 88 patients undergoing resection of HCC were measured by a quantitative enzyme-linked immunosorbent assay. A single pathologist performed histopathologic examination of all tumor specimens. All patients were prospectively monitored for tumor recurrence. RESULTS: The preoperative serum bFGF levels ranged from <0.22 to 71.2 pg/mL (median 10.8 pg/mL). There was significant correlation between high serum bFGF levels and large tumor >5 cm, presence of venous invasion or advanced pTNM stage. Patients with a serum bFGF level >10.8 pg/mL had worse disease-free survival than those with a level <10.8 pg/mL (median disease-free survival 11.2 versus 20 months, P = 0.044). Serum bFGF level >10.8 pg/mL (P = 0.035) and tumor size >5 cm (P = 0.004) were independent preoperative factors that predicted early recurrence after resection of HCC. CONCLUSIONS: This study supports a role of bFGF in tumor growth and invasion in HCC. A high preoperative serum bFGF level appears to be predictive of invasive tumor and early postoperative recurrence. The clinical implications of serum bFGF level in HCC warrant further investigation. 相似文献
45.
Yali Zheng Carmen C. Y. Poon Bryan P. Yan James Y. W. Lau 《Journal of medical systems》2016,40(9):195
Ambulatory blood pressure monitoring (ABPM) has become an essential tool in the diagnosis and management of hypertension. Current standard ABPM devices use an oscillometric cuff-based method which can cause physical discomfort to the patients with repeated inflations and deflations, especially during nighttime leading to sleep disturbance. The ability to measure ambulatory BP accurately and comfortably without a cuff would be attractive. This study validated the accuracy of a cuff-less approach for ABPM using pulse arrival time (PAT) measurements on both healthy and hypertensive subjects for potential use in hypertensive management, which is the first of its kind. The wearable cuff-less device was evaluated against a standard cuff-based device on 24 subjects of which 15 have known hypertension. BP measurements were taken from each subject over a 24-h period by the cuff-less and cuff-based devices every 15 to 30 minutes during daily activities. Mean BP of each subject during daytime, nighttime and over 24-h were calculated. Agreement between mean nighttime systolic BP (SBP) and diastolic (DBP) measured by the two devices evaluated using Bland-Altman plot were ?1.4 ± 6.6 and 0.4 ± 6.7 mmHg, respectively. Receiver operator characteristics (ROC) statistics was used to assess the diagnostic accuracy of the cuff-less approach in the detection of BP above the hypertension threshold during nighttime (>120/70 mmHg). The area under ROC curves were 0.975/0.79 for nighttime. The results suggest that PAT-based approach is accurate and promising for ABPM without the issue of sleep disturbances associated with cuff-based devices. 相似文献
46.
Third ventricular primary cerebral neuroblastoma. Electron-microscopic and immunohistochemical study
A case of third ventricular primary cerebral neuroblastoma with secondary hydrocephalus is reported. Light microscopy showed a cell pattern that resembled either ependymoma or oligodendroglioma. The tumor was confirmed to be neuroblastoma by electron microscopy and immunohistochemistry. Immunoperoxidase staining was positive for neuron-specific enolase and negative for glial fibrillary acidic protein. 相似文献
47.
Proximal gastric vagotomy. The preferred operation for perforations in acute duodenal ulcer. 总被引:1,自引:0,他引:1 下载免费PDF全文
J Boey F J Branicki T T Alagaratnam P J Fok S Choi A Poon J Wong 《Annals of surgery》1988,208(2):169-174
Simple closure, the conventional operation for perforated acute duodenal ulcers, is associated with symptomatic relapse in a large proportion of patients. In order to assess the role of immediate definitive surgery, 78 fit patients with perforated acute ulcers were prospectively randomized to undergo either closure alone or proximal gastric vagotomy with closure (PGV). Patients taking potentially ulcerogenic drugs or who had severe stress were excluded from the study. Both groups were comparable with respect to age, sex, general medical health, duration of perforation, length of ulcer history, and presence of duodenal scarring. There was no hospital mortality. Minor complications occurred in 7.3% after closure and 10.8% after PGV. At 3 years follow-up, the cumulative recurrence rates were 36.6% and 10.6% after closure and PGV, respectively (p = 0.001). Eighty-five per cent of recurrences after closure were symptomatic, and half of them required reoperation. Duodenal scarring itself did not appear to influence the outcome after closure. PGV was not associated with dumping, diarrhea or other unwanted side effects. Although less than that in chronic ulcers, there is a substantial risk of symptomatic relapse after closure of perforated acute duodenal ulcers. With judicious patient selection, PGV effectively reduces this risk without incurring disabling side effects associated with other ulcer operations. 相似文献
48.
Lau KM Lai KK Liu CL Tam JC To MH Kwok HF Lau CP Ko CH Leung PC Fung KP Poon SK Lau CB 《Journal of ethnopharmacology》2012,141(1):250-256
Ethnopharmacological relevance
Astragali Radix (AR) and Rehmanniae Radix (RR) are two traditional Chinese medicines widely used in China for treating diabetes mellitus and its complications, such as diabetic foot ulcer.Aim of study
In our previous study, a herbal formula NF3 comprising AR and RR in the ratio of 2:1 was found effective in enhancing diabetic wound healing in rats through the actions of tissue regeneration, angiogenesis promotion and inflammation inhibition. The aims of the present study were to investigate the herb–herb interaction (or the possible synergistic effect) between AR and RR in NF3 to promote diabetic wound healing and to identify the principal herb in the formula by evaluating the potencies of individual AR and RR in different mechanistic studies.Materials and methods
A chemically induced diabetic foot ulcer rat model was used to examine the wound healing effect of NF3 and its individual herbs AR and RR. For mechanistic studies, murine macrophage cell (RAW 264.7) inflammation, human fibroblast (Hs27) proliferation and human endothelial cell (HMEC-1) migration assays were adopted to investigate the anti-inflammatory, granulation formation and angiogenesis-promoting activities of the herbal extracts, respectively.Results
In the foot ulcer animal model, neither AR nor RR at clinical relevant dose (0.98 g/kg) promoted diabetic wound healing. However, when they were used in combination as NF3, synergistic interaction was demonstrated, of which NF3 could significantly reduce the wound area of rats when compared to water group (p < 0.01). For anti-inflammation and granulation formation, AR was more effective than RR in inhibiting lipopolysaccharide (LPS)-induced nitric oxide production from RAW 264.7 cells and promoting Hs27 fibroblast proliferation. In the aspect of angiogenesis promotion, only NF3 promoted cell migration of HMEC-1 cells.Conclusions
AR plays a preeminent role in the anti-inflammatory and fibroblast-proliferating activities of NF3. The inclusion of RR, however, is crucial for NF3 to exert its overall wound-healing as well as the underlying angiogenesis-promoting effects. The results of present study justified the combined usage of AR and RR in the ratio of 2:1 as NF3 to treat diabetic foot ulcer and illustrated that AR is the principal herb in this herbal formula. 相似文献49.