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排序方式: 共有3559条查询结果,搜索用时 281 毫秒
41.
S. Chua Senior Lecturer/Consultant M. Lee House Officer K. Vanaja Registrar Y. S. Chong Registrar L. Nordstrom Senior Teaching Fellow S. Arulkumaran Professor/Head 《BJOG : an international journal of obstetrics and gynaecology》1998,105(3):352-356
In order to assess the reliability of intrauterine pressure measurements in the third stage of labour, catheter-tip transducers were used in 20 women randomly allocated into two groups of 10. In each case in the first group two catheters were tied together and introduced transcervically into the uterine cavity after delivery of the placenta. In each case in the second group two catheters were inserted independently into the same uterine cavity. The active and cumulative active pressures recorded from the pairs of catheters within each uterine cavity were compared. Comparison of individual active pressure readings from separate transducers revealed good agreement whether the catheters were tied together or were seperate. Cumulative active pressure was very similar when assessed by each catheter in the same uterus. Intrauterine catheter-tip transducers can be used reliably to measure uterine activity in the third stage of labour although there may be minor contraction by contraction differences in recordings of individual active pressures. 相似文献
42.
Bowers KW Edmonds JL Girod DA Jayaraman G Chua CP Toby EB 《The Journal of bone and joint surgery. American volume》2000,82(5):694-704
BACKGROUND: Osteocutaneous radial forearm free flaps have fallen from favor due to pathological fractures of the radius. The purposes of this study were to propose a means to decrease the rate of pathological fracture by prophylactic fixation of the donor-site defect and to evaluate this technique biomechanically. METHODS: Two groups of ten matched pairs of fresh-frozen cadaveric radii were harvested. In Group 1, an eight-centimeter length of radius comprising 50 percent of the cross-sectional area of the bone was removed to simulate an osteocutaneous radial forearm donor-site defect. This defect was created in one member of each pair, with the other bone in the pair left intact. In Group 2, both members of the ten matched pairs of radii had identical defects created as previously described. However, one radius in each pair had a twelve-hole, 3.5-millimeter dynamic compression plate placed across the segmental defect. In each group, five matched pairs were tested to failure in torsion and five matched pairs were tested to failure in four-point bending. RESULTS: In Group 1, the intact radius was a mean of 5.7 times stronger in torsion and 4.2 times stronger in four-point bending than the radius with the segmental resection. In Group 2, the radius that was ostectomized and fixed with a plate was a mean of 4.0 times stronger in torsion and 2.7 times stronger in four-point bending than the ostectomized radius. CONCLUSIONS: Removal of an eight-centimeter segment from the radius dramatically decreased both torsion and bending strength. Application of a plate over the defect in the radius significantly restored the strength of the radius (p = 0.01). 相似文献
43.
Invasive middle ear cholesterol granuloma involving the basal turn of the cochlea with profound sensorineural hearing loss. 总被引:1,自引:0,他引:1
STUDY DESIGN: A retrospective surgical case review. SETTING: A tertiary-care, university teaching hospital. PATIENTS: The authors describe a unique case operated on for a middle ear cholesterol granuloma, which had invaded the cochlea and vestibule causing profound sensorineural deafness. INTERVENTIONS: Extended radical mastoidectomy and labyrinthectomy with musculofascial seal. RESULTS: Successful postoperative outcome with no recurrence seen after 2 years of follow up. CONCLUSION: To the authors' knowledge, this is the first reported case of a primary middle ear cholesterol granuloma with direct invasion into the cochlea. Such invasion of the otic capsule by cholesterol granulomas is rare and presents a diagnostic challenge to the attending otologist and radiologist. Salient points of the case history, pathogenesis, imaging studies, histopathology, and management are presented with a review of the current literature. 相似文献
44.
Phenytoin is widely used for the management of seizures. Fortunately overdosage with this drug is rare. We performed a prospective study to investigate the elimination kinetics of phenytoin in toxic overdose. All patients were only on phenytoin and not on other anticonvulsants. Phenytoin toxicity was defined by clinical features and correlated with drug levels. Daily phenytoin levels were obtained until they were less than or equal to 15 mcg/ml. Nine patients with age ranging from 20 to 66-years-old were recruited. Sex ratio was male:female, 5:4. Initial phenytoin levels ranged from 34 to 57.5 mcg/ml. Serum phenytoin levels of three patients remained relatively constant for 2-5 days before declining in a steady fashion. Phenytoin levels of the remaining patients declined in an almost linear manner. Regression analysis of all patients showed that the slope terms were highly significant (with low P-values) and corresponding R(2) values were close to 1. Different patients have different rates of metabolism; in seven of nine patients, levels declined between 4.6 and 5.9 mcg/ml per day. Knowledge of the rate of elimination assists the clinician in deciding on the best time to reinstitute phenytoin therapy. 相似文献
45.
46.
Anne W M Lee W H Lau Stewart Y Tung Daniel T T Chua Rick Chappell L Xu Lillian Siu W M Sze T W Leung Jonathan S T Sham Roger K C Ngan Stephen C K Law T K Yau Joseph S K Au Brian O'Sullivan Ellie S Y Pang S K O Gordon K H Au Joseph T Lau 《Journal of clinical oncology》2005,23(28):6966-6975
PURPOSE: This randomized study compared the results achieved by concurrent chemoradiotherapy (CRT) versus radiotherapy (RT) alone for nasopharyngeal carcinoma (NPC) with advanced nodal disease. PATIENTS AND METHODS: Patients with nonkeratinizing/undifferentiated NPC staged T1-4N2-3M0 were randomized to CRT or RT. Both arms were treated with the same RT technique and dose fractionation. The CRT patients were given cisplatin 100 mg/m2 on days 1, 22, and 43, followed by cisplatin 80 mg/m2 and fluorouracil 1,000 mg/m2/d for 96 hours starting on days 71, 99, and 127. RESULTS: From 1999 to January 2004, 348 eligible patients were randomly assigned; the median follow-up was 2.3 years. The two arms were well-balanced in all prognostic factors and RT parameters. The CRT arm achieved significantly higher failure-free survival (72% v 62% at 3-year, P = .027), mostly as a result of an improvement in locoregional control (92% v 82%, P = .005). However, distant control did not improve significantly (76% v 73%, P = .47), and the overall survival rates were almost identical (78% v 78%, P = .97). In addition, the CRT arm had significantly more acute toxicities (84% v 53%, P < .001) and late toxicities (28% v 13% at 3-year, P = .024). CONCLUSION: Preliminary results confirmed that CRT could significantly improve tumor control, particularly at locoregional sites. However, there was significant increase in the risk of toxicities and no early gain in overall survival. Longer follow-up is needed to confirm the ultimate therapeutic ratio. 相似文献
47.
Daniel T T Chua Jonathan S T Sham Lucullus H T Leung Gordon K H Au 《Radiotherapy and oncology》2005,77(3):290-294
BACKGROUND AND PURPOSE: To evaluate the treatment outcome in patients with locally recurrent nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiation therapy (IMRT). MATERIALS AND METHODS: Between October 2001 and May 2004, 31 patients with locally recurrent NPC received re-irradiation using IMRT. The rT classification distribution was 3 for rT1, 5 for rT2, 9 for rT3, and 14 for r T4. Median time from first course of radiotherapy to re-irradiation was 51 months. IMRT was performed using step-and-shoot method with nine 4-6 MV photon fields and median prescribed dose was 54 Gy (range: 50-60 Gy). Additional treatments included cisplatin-based induction chemotherapy in 68% and radiosurgery boost with a single dose which ranged from 8.5 to 12.5 Gy in 32%. Median follow-up time was 11 months. RESULTS: After re irradiation, 58% of patients had complete regression of primary tumor. One-year loco-regional progression-free, distant metastasis-free and overall survival rates were 56, 90, and 63%, respectively. Significantly better 1-year local progression-free rate was observed in rT1-3 than r T4 tumor (100 vs. 35%). Grade 3 late toxicities, mostly ototoxicity/cranial neuropathy, occurred in six patients (19%). One-year actuarial rates of late toxicities were 70% for all grades and 25% for Grade 3. CONCLUSION: Our preliminary results showed that good control of rT1-3 NPC can be achieved using IMRT with a dose between 50 and 60 Gy, whereas the outcome for r T4 tumor remained poor. Late toxicities were common but incidence of severe toxicities was relatively low. 相似文献
48.
Cancer-testis genes are coordinately expressed and are markers of poor outcome in non-small cell lung cancer. 总被引:5,自引:0,他引:5
Ali O Gure Ramon Chua Barbara Williamson Mithat Gonen Cathy A Ferrera Sacha Gnjatic Gerd Ritter Andrew J G Simpson Yao-T Chen Lloyd J Old Nasser K Altorki 《Clinical cancer research》2005,11(22):8055-8062
PURPOSE: Cancer-testis genes mapping to the X chromosome have common expression patterns and show similar responses to modulators of epigenetic mechanisms. We asked whether cancer-testis gene expression occurred coordinately, and whether it correlated with variables of disease and clinical outcome of non-small cell lung cancer (NSCLC). EXPERIMENTAL DESIGN: Tumors from 523 NSCLC patients undergoing surgery were evaluated for the expression of nine cancer-testis genes (NY-ESO-1, LAGE-1, MAGE-A1, MAGE-A3, MAGE-A4, MAGE-A10, CT7/MAGE-C1, SSX2, and SSX4) by semiquantitative PCR. Clinical data available for 447 patients were used to correlate cancer-testis expression to variables of disease and clinical outcome. RESULTS: At least one cancer-testis gene was expressed by 90% of squamous carcinoma, 62% of bronchioloalveolar cancer, and 67% of adenocarcinoma samples. Statistically significant coexpression was observed for 34 of the 36 possible cancer-testis combinations. Cancer-testis gene expression, either cumulatively or individually, showed significant associations with male sex, smoking history, advanced tumor, nodal and pathologic stages, pleural invasion, and the absence of ground glass opacity. Cox regression analysis revealed the expression of NY-ESO-1 and MAGE-A3 as markers of poor prognosis, independent of confounding variables for adenocarcinoma of the lung. CONCLUSIONS: Cancer-testis genes are coordinately expressed in NSCLC, and their expression is associated with advanced disease and poor outcome. 相似文献
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