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41.
The aim of this study is to investigate the expression of three prostaglandin E synthase (PGES) isomers in colorectal cancer (CRC) tissue and to evaluate their relationship to clinicopathological factors and patient prognosis. Microsomal PGES (mPGES)-1, mPGES-2, cytosolic PGES (cPGES) and cyclooxygenase (COX)-2 protein expression were analyzed by real-time polymerase chain reaction and Western blot. The localization of each PGES and COX-2 protein was examined by immunohistochemistry in 155 surgical resections and correlated to clinicopathological factors and patient prognosis. mPGES-1 mRNA and protein levels were significantly higher in CRC than in paired normal tissues. mPGES-1 immunoreactivity localized in cancer cells in 43% of cases. mPGES-2 immunoreactivity was significantly more pronounced in cancer cells than in adjacent normal epithelium in 36% of cases. cPGES immunoreactivity was homogeneous in cancer cells and thus determined constitutive. mPGES-1 and mPGES-2 correlated with significantly worse prognosis in stage I–III patients. These results indicate that mPGES-1 and mPGES-2 may each play a role in CRC progression.  相似文献   
42.
Magnetic resonance imaging of anomalous fetuses   总被引:3,自引:0,他引:3  
Magnetic resonance imaging (MRI) has been used sparingly in obstetrics. The reasons for this relate mainly to cost, availability, difficulty obtaining clear images because of fetal movement, and the convenience and utility of ultrasound. However, MRI use is expanding and has the potential to play an important role in selected problem pregnancies. We studied the pregnancies of five women whose fetuses showed anomalies by ultrasound. These included cases of a large body wall defect, a diaphragmatic hernia, hydrocephalus, Meckel-Gruber syndrome, and iniencephaly with a diaphragmatic hernia (the iniencephaly sequence). Three of these examinations followed fetal neuromuscular blockade, and two were associated with oligohydramnios without fetal paralysis. Paralysis provided superior images. The fetal central nervous system, subcutaneous tissue, and liver imaged particularly well. This study illustrates that MRI can enhance and even clarify certain information provided by ultrasound.  相似文献   
43.
: Clinical evaluation of tumor size in cervical cancer is often difficult, and clinical signs of radiation therapy failure may not be present until well after completion of treatment. The purpose of this study is to investigate early indicators of treatment response using magnetic resonance (MR) imaging for quantitative assessment of tumor volume and tumor regression rate before, during, and after radiation therapy.

: Thirty-four patients with cervical cancer Stages IB [5], IIB [8], IIIA [1], IIIB [14], IVA [3], IVB [1], and recurrent [2] were studied prospectively with four serial MR examinations obtained at the start of radiation therapy, at 2-2.5 weeks (20–24 Gy), at 4–5 weeks (40–50 Gy), and 1–2 months after treatment completion. Tumor volume was assessed by three-dimensional volumetric measurements using T2-weighted images of each MR examination. The volume regression rate was generated based on the four sequential MR studies. These findings were correlated with local control, metastasis rate, and disease-free survival. Median follow-up was 18 months (range: 9–43 months).

: The tumor regression rate after a dose of 40–50 Gy correlated significantly with treatment outcome. The actuarial 2-year disease-free survival was 88.4% in patients with tumors regressing to <20% of the initial volume compared with 45.4% in those with ≥20% residual (p = 0.007). The incidence of local recurrence was 9.5% (2 out of 21) and 76.9% (10 out of 13), respectively (p < 0.001). Analysis by initial tumor volume showed that this observation was valid in patients with initial volumes between 40 and 100 cm3. Analysis by FIGO stage confirmed this observation in all patients except those with Stage IB.

: Sequential tumor volumetry using MR imaging appears to be a sensitive measure of the responsiveness of cervical cancer to irradiation. Treatment response can be assessed as early as during the course of radiation therapy by measurement of initial tumor volume and regression rate at 40–50 Gy. In patients with large (>40 cm3) and advanced (Stage ≥ IIIA) tumors, this technique may be helpful in supplementing the clinical examination for response assessment. The identification of patients at high risk for treatment failure may ultimately lead to improved clinical outcome.  相似文献   

44.
Background Flexible endoscopy is a vital component of gastrointestinal surgery. It has and will replace many of the surgical procedures now commonly performed. Flexible endoscopy, unfortunately, is not an integral part of surgical residency training based on resident operative experience as reported by the Residency Review Committee. Moreover, general surgeons have deferred the practice of flexible endoscopy to the gastroenterologists because of concerns over turf battles and referral patterns. The purpose of this study was to assess the overall case load and the economic impact of flexible endoscopy on the practice of general surgery in a community hospital setting.Methods This retrospective review was performed over a 6-month period. The total cases and the total billings of inpatient and outpatient procedures for a group practice of five general surgeons in a community hospital were evaluated. The billings were the actual charges based on current procedural terminology (CPT) codes for these procedures using the Medicare fee schedule.Results Of the 2,159 procedures performed, 1,154 involved flexible endoscopy cases accounting for 54% of all cases (1,154 of 2,159) performed from February 1, 2003 to July 31, 2003. Flexible endocopy accounted for 43% of the total charges. A. total of 46 surgical procedures and 216 future endoscopies were generated from the flexible endoscopic procedures. Future endoscopic cases were for surveillance of colonic neoplasia and Barrett’s esophagus.Conclusions Flexible endoscopy contributed to a major portion of the caseload and revenue generated by the general surgery group studied. The overall impact of flexible endoscopy is even greater than reported because of the future endoscopic surveillance cases or surgical interventions generated on the basis of endoscopic findings.  相似文献   
45.
PURPOSE: To document the high occurrence of complete spontaneous regression of retinoblastoma in a Taiwan series. PATIENTS AND METHODS: Cases of retinoblastoma (133 eyes of 110 patients) at a single Taiwanese hospital from 1978 to 2002 were reviewed. RESULTS: Complete spontaneous tumor regression and phthisis bulbi were noted in 7 eyes of 7 patients. The regression rate was 5.3%, which is higher than previous reports of 1% to 2%. Tumor regression was associated with a common course of acute painful inflammation and ended with a shrunken, nonfunctioning eye. No residual vision was noted in any patient. CONCLUSION: Delayed diagnosis and advanced stage of the disease in this series of Taiwanese patients probably led to the massive intratumoral necrosis and resulted in phthisic change of the globe.  相似文献   
46.
47.
Fitton TP  Bethea BT  Borja MC  Yuh DD  Yang SC  Orens JB  Conte JV 《The Annals of thoracic surgery》2003,76(5):1680-5; discussion 1685-6
BACKGROUND: The morbidity of lung transplantation is higher than other solid organ transplants. Little is known about the outcomes of patients who require pulmonary resection following lung transplantation. We reviewed our experience to evaluate and discern any variables affecting outcome of pulmonary resections performed following lung transplantation. METHODS: A retrospective review of the lung transplant database was performed. Data are presented as mean +/- standard error (median). RESULTS: A total of 136 lung transplants (80 single lung transplants [SLT], 55 bilateral lung transplants [BLT], and 3 heart-lung transplants [HLT]) were performed from August 1995 to February 2002. Twelve pulmonary resections, 7 lobectomies, and 5 wedge resections were performed on 11 patients. The indication for lobectomy was infection in 5 of 7 lobectomies (3 fungal, 2 bacterial), mass in 1 of 7, and infarction in 1 of 7. The indication for wedge resection was native lung hyperinflation in 4 of 5 wedge resections and mass in 1 of 5. The native lung was resected in 3 of 7 lobectomies and 4 of 5 wedge resections. An allograft lobectomy was performed following 1 SLT and 3 BLT and a wedge resection was performed after 1 SLT. The mean time to pulmonary resection was 12.4 +/- 3.9 (9.1) months. Survival postresection was 17.2 +/- 5.8 (8.3) months and 5 of 11 patients are still alive. There were no bronchial stump leaks following lobectomy. CONCLUSIONS: Major pulmonary resections can safely be performed following lung transplant. We recommend early intervention to optimize outcomes.  相似文献   
48.
Background. Both docetaxel (TXT) and irinotecan (CPT-11) are active chemotherapeutic agents for gastric cancer. We designed a biweekly administration regimen of TXT combined with CPT-11 for 4 weeks as one cycle in patients with inoperable or recurrent gastric cancer, and conducted a dose-escalation study. Methods. Patients with histologically confirmed gastric cancer were treated with the regimen. The dosage levels of TXT and CPT-11 were as follows: level 1, 30mg/m2 and 50mg/m2; level 2, 35 and 50mg/m2; level 3, 40 and 50mg/m2; level 4, 40 and 60mg/m2; and level 5, 50 and 60mg/m2. The dose escalation was based on the dose-limiting toxicity (DLT) observed during the first cycle. Results. Grade 4 neutropenia was observed at level 3, but no other DLT was observed at less than level 4 during the first cycle. However, three patients at level 3 could not continue treatment without a decrease in the dosage after the second cycle. Based on these results, level 2 was considered to be the clinically recommended dosages. Conclusion. Biweekly TXT and CPT-11 was well tolerated. The recommended dosages of TXT and CPT-11 for a phase II trial are 35mg/m2 and 50mg/m2, respectively.  相似文献   
49.
With limited near-field resolution and accessible acoustic windows, sonography has not been advocated for assessing central nervous system injuries in the shaken-baby syndrome. Our purpose was to correlate high-resolution ultrasonographic characteristics of central nervous system injuries in whiplash injuries and the shaken-baby-syndrome with MRI and CT. Ultrasonographic images of 13 infants, aged 2–12 months, with whiplash or shaking cranial trauma were reviewed and compared with MRI in 10 and CT in 10. Five patients had serial ultrasonography and MRI or CT follow-up from 1 to 4 months after the initial injury. With ultrasonography we identified 20 subdural haematomas. MRI and CT in 15 of these showed that four were hyperechoic in the acute stage, three were mildly echogenic in the subacute stage, and that one subacute and seven chronic lesions were echo-free. Five patients had acute focal or diffuse echogenic cortical oedema which evolved into subacute subcortical hyperechoic haemorrhage in four, and well-defined chronic sonolucent cystic or noncystic encephalomalacia was seen at follow-up in two. Using ultrasonography we were unable to detect two posterior cranial fossa subdural haematomas or subarachnoid haemorrhage in the basal cisterns in three cases, but did show blood in the interhemispheric cistern and convexity sulci in two. Ultrasonography has limitations in demonstrating abnormalities remote from the high cerebral convexities but may be a useful adjunct to CT and MRI in monitoring the progression of central nervous system injuries in infants receiving intensive care. Received: 25 October 2000 Accepted: 25 October 2000  相似文献   
50.
Head injury in child abuse: evaluation with MR imaging   总被引:3,自引:0,他引:3  
To evaluate the usefulness of magnetic resonance (MR) imaging in the diagnosis of head injury in child abuse, the authors compared the findings at head MR imaging and computed tomography (CT) in 19 abused children. Subdural hematomas (15 cases), cortical contusions (six cases), and shearing injuries (five cases) were demonstrated to particular advantage with MR imaging. CT remained superior in the detection of subarachnoid hemorrhage. MR imaging appears to be valuable in the assessment of patients with suspected intracranial injury due to child abuse.  相似文献   
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