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21.
Feng-Yuan Liu Chien-Yu Lin Joseph T Chang Shu-Hang Ng Shy-Chyi Chin Hung-Ming Wang Chun-Ta Liao Sheng-Chieh Chan Tzu-Chen Yen 《Journal of nuclear medicine》2007,48(10):1614-1619
Conventional work-up (CWU) with chest radiography, abdominal ultrasonography, and skeletal scintigraphy has limited value in M staging of nonkeratinizing nasopharyngeal carcinoma (NPC). Our aim was to evaluate whether (18)F-FDG PET could replace CWU by comparing their diagnostic efficacies. METHODS: Patients with histologically proven nonkeratinizing NPC and no prior treatment were prospectively enrolled. All study participants underwent CWU and (18)F-FDG PET for primary M staging. Distant metastasis was considered to be present if there was any reliable evidence identified within 1 y after diagnosis. The comparative diagnostic efficacies of (18)F-FDG PET, CWU, and the combination of (18)F-FDG PET and CWU (PET+CWU) were evaluated using the areas under the receiver-operating-characteristic (ROC) curves. RESULTS: Sixty-one (20.3%) of 300 eligible patients were found to have distant metastases. On a patient-based analysis, (18)F-FDG PET was found to be more effective than CWU (P < 0.001), whereas it was equally effective with PET+CWU (P = 0.130). On region-based analyses, (18)F-FDG PET was more effective than skeletal scintigraphy and chest radiography for detecting bone metastases (P < 0.001) and chest metastases (P < 0.001), respectively. (18)F-FDG PET and abdominal ultrasound were equally effective for detecting hepatic metastases (P = 0.127). On region-based analyses, the combination of (18)F-FDG PET and CWU did not yield any noticeable increase in diagnostic efficacy. CONCLUSION: (18)F-FDG PET can replace CWU in primary M staging of nonkeratinizing NPC. 相似文献
22.
Elaine C McKevitt Eric Calvert Alex Ng Richard K Simons Andrew W Kirkpatrick Leanne Appleton D Ross G Brown 《Canadian journal of surgery》2003,46(3):211-215
INTRODUCTION: Elderly patients who suffer trauma have a higher mortality and use disproportionately more trauma resources than younger patients. To compare these 2 groups and determine the outcomes and characteristics of elderly patients, we reviewed patients in these 2 groups admitted and treated in our tertiary care provincial trauma centre. METHODS: From the provincial trauma registry we selected a cohort of 40 geriatric patients (group 1) (> or = 65 yr of age) with an ISS of 16 or more who were admitted to and spent time in our trauma service for more than 48 hours and compared them with a similar randomly selected cohort of 44 patients (group 2) aged 20-30 years. Family physicians were contacted for follow-up of these patients 2 years after discharge. We considered length of hospital stay, complications, disposition of the patients and use of consultation services. RESULTS: Patients in group 1 had a mean age of 72.1 years (range from 65-98 yr) and a mean ISS of 27.3 (range from 17-50). Patients in group 2 had a mean age of 26.3 years (range from 22-29 yr) and a mean ISS of 26.3 (range from 17-54). Hospital stay was significantly longer in the group 1: 34.5 days (95% confidence interval [CI]: 24-44 d) versus 21.6 days (95% CI: 15-28 d). More elderly patients experienced complications (35 v. 13, p < 0.001) and required medical consultations (35 v. 26, p < 0.001). In-hospital death rates were 8% (3 of 40) and 4% (2 of 44) respectively (p = 0.3). Fewer geriatric patients could be discharged home (35% [14 of 40] v. 27% [22 of 44], p = 0.056) or to rehabilitation facilities (28% [11 of 40] v. 34% [15 of 44], p = 0.3). Five geriatric patients were discharged to nursing homes (p = 0.007). Of the geriatric patients discharged to rehabilitation facilities or home, 75% were independent 2 years after discharge. CONCLUSIONS: Aggressive care for geriatric trauma patients is warranted, and resources should be directed toward rehabilitation. Based on our findings, we expect that creating a directed care pathway for these patients, targetting complications and earlier discharge, will further improve their outcomes. 相似文献
23.
H. N. Koong H. S. Chan R. Nambiar K. C. Soo J. Ho H. S. Ng E. H. Ng 《ANZ journal of surgery》1996,66(12):813-815
Background : Mortality rates from gastric cancer, apart from those derived from Japanese series, remain poor. This paper sought to determine the present outcome of gastric carcinoma in a predominantly Chinese population in Singapore. Prognostic factors useful in predicting survival were also evaluated in this population. Method : All cases of histologically confirmed gastric adenocarcinoma presenting in 1992 were entered into a prospective database. Prognostic factors related to age, sex, site of disease, depth of invasion, histological grade, nodal status and stage of disease were evaluated in patients with resectable disease to determine their utility in predicting survival. Results : Of 1310 consecutive patients with histologically proven adenocarcinomas, 37% had distant metastases at presentation predominantly in the liver (21%) and peritoneal cavity (20%). Sixty-four per cent of patients underwent surgery and in only 51% of these patients was resection of the turnour possible. Stages 111 and IV (T4N2) locally advanced disease were present in 38% of patients. Thus the majority of patients presented with late or metastatic disease (75%, stages 111 and IV). Sixty per cent of patients were alive at I year and 40% at 2 years after resection of the tumour (Kaplan-Meier survival plots). In contrast, no patient survived longer than a year if the tumour was not resectable (P < 0.001, log-rank test). Median survival of patients without surgery was 12 weeks. Median survival for patients with resected stage IV disease was 23 weeks, compared to 18 weeks after surgical bypass. Age, sex, site, depth of invasion and histological grade did not significantly predict survival. Patients with node-negative disease survived longer (2 year, 70%) than those with nodal involvement (2 years, 44%; P = 0.06, log-rank test). Pathologic staging with the TNM system was useful in predicting survival (P < 0.001). Sixty per cent of patients with stage I and II disease were alive at 2 years compared to 54% with stage III disease and 0% with stage IV disease. Conclusion : The prognosis of stomach cancer remains poor, due predominantly to late presentation. Pathologic TNM staging and nodal status were useful in predicting survival outcome after resection. If the tumour were resectable, survival was appreciable even in patients with advanced stage III (2 years, 54%) and stage IV (1 year, 40%) disease. Strategies to improve outcome should focus on early detection of gastric carcinomas. 相似文献
24.
V. A. Dunand C.-M. Ng J. A. Wade J. Bwayo F. A. Plummer K. S. MacDonald 《Tissue antigens》1997,49(4):397-402
The genes of the major histocompatibility complex (MHC) are amongst the most polymorphic loci known in the human population. The population genetics of the MHC encoded HLA loci of sub-Saharan Africa are of major interest because of their particular genetic diversity. Here we report on the HLA-DR 52- and 51-associated determinants of the DRB1 loci observed in 165 East African individuals studied in Nairobi, Kenya. The HLA-DR typing was done by serologic and by molecular DNA techniques (PCR-SSOP). The most frequent allele identified was DRB1*1101, followed by DRB1*1503 and DRB1*1302. Some unexpected alleles were repeatedly identified: DRB1*1108, DRB1*1316 and DRB1*1421. Most oftheDR 52-and 51-associated DRB1 alleles were correctly identified by serology as part of the DR3, DR5, DR6 and DR2 groups respectively. The HLA-DRB1 profile reported here corroborates previous genetic and linguistic data supporting the concept that the Eastern African Black population is genetically distinct from other African Black populations. This has important implications in public health issues related to the genetic profile of a population (transplantation, vaccine design for example). 相似文献
25.
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27.
John Hill Robert C. Stuart Hin K. Fung Enders K.W. Ng Fanny M. Cheung Sidney C.S. Chung C. Andrew van Hasselt 《The Laryngoscope》1997,107(10):1373-1377
The aim of this study was to investigate the origin of globus pharyngis with particular reference to esophageal disorders such as gastroesophageal reflux disease (GERD), motility disorders, structural abnormalities, other gastrointestinal tract diseases, and psychological profile. Previous studies on this subject using 24-hour pH monitoring give conflicting results and are hampered by the high background prevalence of asymptomatic GERD in the normal Western population. The local Chinese population is known to have a very low background level of GERD and therefore is an ideal study population. Twenty-six patients with globus pharyngis underwent 24-hour ambulatory pH monitoring, esophageal manometry, and esophagogas-troduodenoscopy with lower esophageal biopsy. A control group of 20 patients presenting with non-ulcer dyspepsia was similarly investigated. Personality profiles of the globus pharyngis subjects and an appropriate control group were assessed. Eight of the globus pharyngis group (30.7%) had evidence of GERD, whereas only one of the controls (5%) demonstrated GERD on 24-hour esophageal pH monitoring (P < 0.05). The manometric and personality profile studies did not show significant differences between study and control groups. We concluded that the finding of GERD in patients with globus pharyngis is not a coincidental finding but that there is a true association between GERD and globus pharyngis. 相似文献
28.
Reproducible model of post-infarction left ventricular dysfunction: haemodynamic characterization by conductance catheter. 总被引:4,自引:0,他引:4
A K Hasnat Enno T van der Velde Jimmy K F Hon Magdi H Yacoub 《European journal of cardio-thoracic surgery》2003,24(1):98-104
OBJECTIVE: The understanding of pathophysiology and cellular mechanisms of chronic heart failure requires the creation of appropriate and accurately characterized animal models, thus enabling meaningful evaluation of evolving medical and surgical therapies. METHODS: The left anterior descending and its diagonal branch were ligated in 12 sheep to induce left ventricular dysfunction. RESULTS: Study of left ventricular pressure-volume loops 3 months post-operatively showed a significant deterioration of both systolic and diastolic indexes of left ventricular function. The left ventricular end-diastolic pressure increased from 3+/-1 to 7+/-1 mmHg (P<0.001) along with a substantial increase in end-diastolic volume from 78+/-8 to 121+/-6 ml (P=0.002) and a significant decrease in cardiac output from 2+/-0.2 to 1.5+/-0.2 l/min (P=0.001). The left ventricular end-systolic pressure-volume relationship deteriorated from 2.7+/-0.37 to 0.7+/-0.16 mmHg/ml (P=0.0002) along with a significant reduction in the pre-load recruitable stroke work (P=0.001). The ejection fraction decreased from 34+/-2% to 16+/-4% (P<0.001) with a significant decrease in +dp/dt and -dp/dt (P=0.009). The mean systemic blood pressure, however, was maintained due to a substantial increase in the systemic vascular resistance (P=0.007). CONCLUSION: This study describes a reproducible large animal model of left ventricular dysfunction. This model is potentially useful to study the pathogenesis of remodelling, surgical management of heart failure and development of novel treatment strategies. 相似文献
29.
Prognostic implications of patterns of failure for gastrointestinal leiomyosarcomas. 总被引:16,自引:0,他引:16
One hundred ninety-one patients with gastrointestinal leiomyosarcomas were analyzed to determine the prevalence in patterns of failure and the factors predicting those at higher risk of relapse at specific sites. Of 100 assessable patients who died of disease, 89% were found to have peritoneal tumor, 78% had liver metastases, and 32% had extraabdominal metastases. Of 132 patients (69%) with initial complete resection of the primary tumor, only 10% (n = 13) remained free of disease as of the last follow-up. The median interval to recurrence was 18 months; 60% of all recurrences occurred within 2 years after surgery. Half of these patients (n = 61) had metastases (predominantly in the liver) as the initial recurrence. Factors significantly associated with improved survival after relapse were initial disease-free interval of 18 months or more, recurrences either isolated to the peritoneal cavity or within the liver, or complete resection of peritoneal recurrences or liver metastases. In contrast, those patients with recurrences at multiple sites or unresectable disease had significantly shorter survival times. The presence of extraabdominal metastases also heralded an equally poor outcome. In conclusion, a multimodality approach is necessary to improve outcome from this disease because the liver and peritoneal cavity represent predominant sites of failure. Complete resection of isolated peritoneal or hepatic metastases improves survival and should be attempted when feasible. 相似文献
30.
Background : Electrohydraulic lithotripsy (EHL) has been available for endoscopic treatment of urinary calculi since 1960, but the large probe size and concerns regarding safety had previously restricted its use to the treatment of bladder calculi. However, recent refinements have made it particularly suitable for the treatment of ureteric calculi. Methods : The authors report their initial experience using EHL in conjunction with mini-ureteroscopy in the treatment of 94 ureteric calculi in 89 patients. The size of the calculi ranged from 3 to 19 mm in diameter, with a mean of 8.2 mm. The mean operating time was 29 min, ranging from 10 to 120 min. Results : A complete fragmentation rate of 91.5% of the calculi was achieved. There were no major complications and a low incidence of minor complications: haematuria (2.2%), urinary tract infection (3.4%) and postoperative ureteric colic (2.2%). There were four cases of minor ureteric perforations (4.5%); all were successfully treated using conservative measures. Conclusions : It is concluded that EHL is a safe and effective method of treating ureteric calculi. 相似文献