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231.
The purpose of this study was to identify the prognostic significance of pulmonary and liver involvements present at diagnosis in children with Wilms' tumor. From 1971 to 2002, 57 patients with stage IV Wilms' tumor were diagnosed, treated, and followed in the authors' institution. Metastases were detected by chest radiography, abdominal ultrasonography, and/or thoracoabdominal computed tomography. Nephrectomy with tumor resection was performed and appropriate chemotherapy was given to all the patients. The Kaplan-Meier survival method was used to calculate survival. The log-rank test was used to compare the groups with respect to survival. The age range was 1.25 to 15 years (median 4 years). Thirty-seven patients had only lung metastases, 12 had only liver metastases, 6 had both lung and liver metastases, 1 had adrenal gland metastases, and 1 had other site metastases. The overall survival rate in the whole group was 37.1%. The overall survival rates for lung and liver metastases were 50.2% and 16.6%, respectively. The overall survival rates were significantly different between the two groups (P = 0.005). Only one patient survived in the group with liver involvement. Liver involvement at diagnosis indicates a worse prognosis than lung involvement. Wilms' tumor patients with liver metastases should be treated with more intensive regimens than those with lung metastases.  相似文献   
232.
A 22-year-old man presented with fever and ulceration of the oral mucosa. The patient had pharyngeal and esophageal candidiasis. For the 3 weeks prior to presentation, he had been taking approximately 1000 mg/day of flowering herbs (Hypericum perforatum L, known as St. John's wort) for treatment of depression. A complete blood count on the first day of hospitalization showed agranulocytosis and normocytic anemia. His condition worsened, and he developed progressive dysphagia. A bone marrow biopsy on day 3 revealed bone marrow necrosis. After the diagnosis was established (day 3 of hospitalization), treatment with granulocyte colony-stimulating factor 48 U/day, intravenous immunoglobulin 400 mg/kg, and amphotericin B 100 mg/day was initiated. The patient did not respond, and died within one week of the diagnosis. This cases suggests that Hypericum species may lead to severe hematologic toxicity, with conditions involving bone marrow necrosis.  相似文献   
233.
The treatment of melanoma with an emphasis on immunotherapeutic strategies   总被引:1,自引:0,他引:1  
Melanoma continues to be one of the most difficult to treat of all solid tumors. Many new advances have been made in the surgical management of melanoma, including new guidelines for margins of excision, as well as sentinel node biopsy for the diagnosis of lymph node micrometastases. The search continues for an effective adjuvant melanoma treatment that can prevent local and distant recurrences. Melanoma is one of the most immunogenic of all tumors, and several clinical trials testing the immunotherapy of melanoma have been conducted, including trials in interferon, interleukin-2, and melanoma vaccines. Here we discuss many of the recent clinical trials in the surgical management of melanoma, in addition to the advances that have been made in the field of immunotherapy. A new second-generation melanoma vaccine, DC-MelVac (patent # 11221/5), has recently been granted FDA approval for Phase I clinical trials and will be introduced in this review.  相似文献   
234.
Cystic nephroma (CN) and pleuropulmonary blastoma (PPB) are rare tumors. In the cases presented here, a 13-month-old boy underwent right radical nephrectomy for CN. From the family history we learned that four years ago the patient's older sister underwent left radical nephrectomy for CN at a different center when she was 4 years old. A lung tumor was detected in the sister one year after nephrectomy. Biopsy from the lung tumor revealed PPB, and the sister died within one year after biopsy. To the knowledge of the authors, these cases represent the second reported familial occurrence of CN and the fourth of CN and PPB.  相似文献   
235.

Background/purpose

Flow of a fluid through a collapsible tube is under the influence of various factors including the external compressing pressure. The intraabdominal pressure (IAP) should influence the flow through the ureter. Therefore, an experimental study was planned to investigate the effects of ureteral length and external compressing pressure onto the intrapelvic pressure (IPP) in rabbits.

Methods

Nineteen adult rabbits were used for the experiment. Under general anesthesia, an intraperitoneal and an intrapelvic catheter were placed to measure IAP and IPP. A urethral catheter was placed for bladder decompression. After this standard preparation, a ureteric stent was placed in the ureter in group 1 (n = 7). Distal or proximal ureter transection was performed in group 2 (n = 6) and group 3 (n = 6), respectively. Basal pressure measurements have been recorded. Then the pressures were recorded every 5 minutes, and IAP was increased gradually for 4 cm of water pressure in each subsequent 30-minute period. All analyses were performed for a standard IAP interval (5 to 25 cm H2O).

Results

IAP did not differ between groups (P = .08). IPP values were significantly higher than the corresponding IAP values in each group (P = .0001). IPP showed significant difference between IAP values of groups (P = .0001). IPP was significantly increased in group 2 when compared with group 1 and group 3 (P = .0001; P = .0001), but no difference was encountered between groups 1 and 3 (P = .1). There has been a strong relationship between IPP and IAP values in all groups. The Rsq values were 0.912, 0.783, and 0.943 for group 1, group 2, and group 3, respectively (P < .0001). Mathematic relations between IPP and IAP also were analyzed. The relations were IPP = 3.9 + 1.10 × IAP, IPP = 10.3 + 1.10 × IAP, and IPP = 3.3 + 1.12 × IAP for groups 1, 2, and 3, respectively.

Conclusions

Renal pelvis pressure responds with augmented increases to increments in IAP in urinary tracts with different ureteric lengths. Increase in IPP is more pronounced in longer ureters possibly owing to increased resistance to flow. Prevention of ureteric wall collapse reverses the augmented increase in IPP responses. Therefore, both the length and collapsibility of the ureter play a detrimental role in the generation of augmented IPP responses to increments in IAP. The magnitude of IPP as a response to increments in IAP can be estimated by using mathematical relations between IPP and IAP. Increases in IAP may simulate proximal ureteric obstruction and may take part in the pathogenesis of hydronephrosis.  相似文献   
236.
The treatment and early diagnosis of choledochal cyst are very important to prevent complications of the disease. Delay in treatment can cause lethal complications like biliary cirrhosis and increased morbidity in patients. We studied 26 children with choledochal cyst retrospectively for their clinical presentation, and for the diagnostic tools and treatment modalities, used. The most common findings of choledochal cyst in our series were abdominal pain, vomiting, and ictures in contrast to the classical triad of the disease of jaundice, mass and pain. The most useful diagnostic tool was abdominal ultrasonography. For the treatment, we preferred Roux-en-Y hepaticojejunostomy to the internal drainage procedures, and the results were excellent with minimal mortality and morbidity. We underline prompt diagnosis and treatment to prevent late complications of the disease.  相似文献   
237.
Bartter's syndrome is characterized by hypochloremia, hypokalemia, metabolic alkalosis associated with renal potassium leakage, and normal blood pressure despite increased plasma renin activity. Although association of empty sella with Gitelman syndrome has been reported, no association has been reported with Bartter's syndrome. Here we report a patient with Bartter's syndrome and empty sella. A 12 month-old male patient presented with a history of nausea, vomiting, abdominal distension, constipation, and edema in the lower extremities that had begun in the early postnatal period. The patient was born at 32 weeks gestation by operative delivery for polyhydramnios. Blood pressure was normal. Serum sodium, potassium, calcium, phosphate, chloride, albumin and alkaline phosphatase levels were 129 mEq/l, 2.5 mEq/l, 9 mg/dl, 3.8 mg/dl, 72 mg/dl, 4.2 g/dl and 1285 IU/l, respectively. Serum magnesium level was normal. Arterial blood gas levels revealed pH 7.55 (normal, 7.35-7.45), PCO2 33.6 mm/Hg (36-46), base excess +7.1 (+/- 2.3), and total CO2 33.6 mmol/l (23-27). Renin and aldosterone levels were elevated. Urine had pH 8.0 and specific gravity 1.010. Urinary calcium excretion was 22.8 kg/day (urine calcium/creatinine ratio 0.46). Urinary potassium and chloride levels were elevated. MRI of the brain was normal except for partially empty sella. We present the first pediatric patient with the association of Bartter's syndrome and empty sella.  相似文献   
238.
Conservative treatment of an epidural hematoma is not always effective in children. We describe an 8-year-old boy who had been followed up conservatively for 10 days at a local hospital due to acute epidural hematoma. A new CT revealed an expansion of the former hematoma accompanied by a thick hyperdense layer. Because the patient presented with symptoms of elevated intracranial pressure, an immediate craniotomy was performed to evacuate the hematoma. The ossified layer, which was densely adhered to the dura mater, was also completely removed. Rapid ossification and/or calcification of an epidural hematoma appearing 10 days after a head injury have not been reported previously. Possible mechanisms of rapid ossification are also discussed in relation to the present report, and the relevant literature is reviewed.  相似文献   
239.
240.
Jitter values are calculated in reference to a triggering potential during single-fiber electromyography (SFEMG) performed during voluntary contraction. When there are more than two single-fiber action potentials (SFAP) and the selected triggering potential is from an abnormal end-plate, all the jitters calculated from the same trace will be affected. In this study, the effect of triggering potential on calculated jitter was investigated in myasthenic and healthy volunteers by switching the triggering potential and recalculating the jitter off-line. Selecting a triggering potential from an abnormal end-plate increased the number of abnormal individual jitters as well as the mean jitter. Therefore, if the equipment software has the capacity to change the trigger potential, the triggering potential should not be from an abnormal end-plate if all possible jitter values are to be calculated for traces having three or more single-fiber potentials. Otherwise, only one jitter value should be included from any one trace to prevent false-positive results.  相似文献   
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