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71.
目的 探讨CT仿真内镜在结肠癌诊治中的临床应用。方法 收集 30例结肠癌的CT仿真内镜、电子结肠镜及手术病理的材料 ,并从肿块分型、病变环周侵犯范围及病变长度等三方面进行比较。结果 结肠癌的CT仿真内镜征象分析 :(1)肿块分型 :肿块型 11例、溃疡型 11例、浸润型 8例。 (2 )环周侵犯范围 :侵犯肠腔≤ 1/2共 4例、侵犯肠腔 1/4- 3/4共 6例、侵犯肠腔≥ 3/4共 2 0例。 (3)病变长度 :1.0 - 3.0cm共 7例 ,3.1- 5 .0cm共 10例 ,5 .1- 1.0cm共 13例。CT仿真内镜、电子结肠镜与手术病理结果对照 :(1)CT仿真内镜与手术病理结果比较 :肿块分型相同 2 6例 ,不同 4例 ;环周侵犯范围相同 2 5例 ,不同 5例 ;病变长度相同 2 3例 ,不同 7例。 (2 )电子结肠镜与手术病理结果比较 :肿块分型相同 2 2例 ,不同 8例 ;环周侵犯范围相同 2 8例 ,不同 2例 ;病变长度相同 14例 ,不同 3例 ,电子结肠镜不能确定病变长度 13例。结论 CT仿真内镜能获得类似电子结肠镜所见的图像 ,可以作为不能进行电子结肠镜检查 ,或电子结肠镜检查观察不全面的结肠癌患者的一种良好补充检查手段。  相似文献   
72.
The effects of acute and chronic stages of carrageenan-induced air-pouch inflammation on the pharmacokinetics of prednisolone were studied in male Wistar rats. Chronic inflammation produced a significant increase in the area under the curve (AUC) of prednisolone compared to control animals (6594 ± 2144 vs 3530 ± 2164 µg · hr/ L). The effect of acute inflammation was not significant (AUC = 4996 ± 3813). Both acute and chronic inflammation also reduced thein vitro plasma protein binding of prednisolone, the reduction being much greater after chronic inflammation. The AUC of free prednisolone after chronic inflammation was 3141 µg · hr/L, compared to 1121 µg · hr/L in the control group and 1823 µg · hr/L after acute inflammation. The mean values of half-life and apparent volume of distribution at steady-state in each group were similar. These results indicate that prednisolone must be used with caution in the treatment of inflammatory diseases because of higher free concentrations of the steroid.  相似文献   
73.
To compare the results of laparoscopy with laparotomy in the management of ovarian masses not suspected of being malignant, a retrospective review was made of 115 patients with ovarian masses operated on, 50 by laparotomy and 65 by laparoscopy, in the Department of Obstetrics and Gynaecology, Prince of Wales Hospital, Hong Kong, from November 1, 1992, to October 31, 1993. In the laparoscopy group, the average size of the ovarian masses was smaller, and there was a significant reduction in the intraoperative blood loss, postoperative analgesic requirement, morbidity (particularly febrile morbidity and urinary retention), length of hospital stay, and recuperation period. The incidence of rupture of the ovarian mass was not related to the operative approach but to the underlying pathology. Two patients in the laparoscopy group were converted to laparotomy, and 1 in the laparotomy group required a second laparotomy. The operating time was longer in the laparoscopic approach, but this could be reduced with experience and improved technique in specimen removal. Laparoscopy appears to be a better approach than laparotomy in the management of ovarian masses where malignancy is not suspected and a competent surgeon is available.  相似文献   
74.
Although managed care may be more effective than fee-for-service in containing health care costs in the United States, it is less effective in countries with a national health service. In Hong Kong, costs have been contained despite the fact that 95% of general practitioners still practice on a solo, fee-for-service basis. The author describes in detail how the system of tax-based hospitals guarantees universal access without escalating costs.  相似文献   
75.
The pharmacokinetics and pharmacodynamics of prolonged oral etoposide chemotherapy were investigated in 15 women with metastatic breast cancer who received oral etoposide 100 mg as a single daily dose for up to 15 days. There was considerable interpatient variability in the day 1 pharmacokinetic parameters: area under the plasma concentration time curve (AUC) (0–24 h) 1.95±0.87 mg/ml per min (mean ± SD), apparent oral clearance 60.9±21.7 ml/min per 1.73 m2, peak plasma concentration 5.6±2.5 g/ml, time to peak concentration 73±35 min and half-life 220±83 min. However, intrapatient variability in systemic exposure to etoposide was much less with repeated doses. The intrapatient coefficient of variation (CV) of AUC for day 8 relative to day 1 was 20% and for day 15 relative to day 1 was 15%, compared to the day 1 interpatient CV of 45%. Neutropenia was the principal toxicity. Day 1 pharmacokinetic parameters were related to the percentage decrease in absolute neutrophil count using the sigmoidal Emax equation. A good fit was found between day 1 AUC and neutrophil toxicity (R 2=0.77). All patients who had a day 1 AUC>2.0 mg/ml per min had WHO grade III or IV neutropenia. The predictive performance of the models for neutrophil toxicity was better for AUC (percentage mean predictive error 5%, percentage root mean square error 18.1%) than apparent oral clearance, peak plasma concentration, or daily dose (mg/m2). A limited sampling strategy was developed to predict AUC using a linear regression model incorporating a patient effect. Data sets were divided into training and test sets. The AUC could be estimated using a model utilizing plasma etoposide concentration at only two time points, 4 h and 6 h after oral dosing (R 2=98.9%). The equation AUCpr=–0.376+0.631×C4h+0.336×C6h was validated on the test set with a relative mean predictive error of –0.88% and relative root mean square error of 6.4%. These results suggest monitoring of AUC to predict subsequent myelosuppression as a strategy for future trials with oral etoposide.Division of Haematology and Medical Oncology, Peter MacCallum Cancer Institute, Locked Bag 1, A'Beckett St, Melbourne 3000, Australia  相似文献   
76.
In two patients, a woman aged 34 and a man aged 38, toxic shock-like syndrome was diagnosed. This is a serious and potentially lethal disease characterized by multiorgan failure, fever, skin lesions and shock and caused by the exotoxin of Streptococcus pyogenes. Both patients had an invasive Lancefield group A beta haemolytic streptococcal infection. The first patient presented with a skin wound at the right knee and later developed shock and thrombosis, in the second a flu-like disease was complicated by respiratory insufficiency, rhabdomyolysis and acute renal insufficiency. Timely recognition of this infection may reduce the risk of complications such as adult respiratory distress syndrome, disseminated intravasal coagulation and necrotizing fasciitis. Both patients eventually recovered after antibiotic and intensive supporting therapy. This infection can be life-threatening and the fatality rate is 15-35% even if patients received appropriate antimicrobial therapy, supportive care, and, where necessary, surgical debridement.  相似文献   
77.
The aim of the study was to evaluate the usefulness of the magnetic resonance (MR) perfusion maps in the detection of liver tumor perfusion following transcatheter arterial chemoembolization (TACE). MR dynamic susceptibility contrast-enhanced imaging was performed in 12 patients with 10 confirmed hepatocellular carcinoma and 2 confirmed hepatic metastasis using single-shot echoplanar pulse sequence. Time-intensity curves for all hepatic tumors showed a transient signal drop and the hepatic blood volume (HBV) maps were reconstructed. On the HBV maps, most tumors (80%) demonstrated hyperperfusion before TACE and hypoperfusion following TACE. The site and the degree of residual hyperperfusion within the tumor on the HBV maps correlated well with the areas of hypervascularity on the angiograms. In conclusion, the MR perfusion maps can be a promising technique for detecting the perfusion of the residual tumor tissue following TACE.  相似文献   
78.
Hypertrophic olivary degeneration (HOD) is a rare type of neuronal degeneration involving the dento-rubo-olivary pathway. It is distinguished from other types of neuronal degeneration in that hypertrophy, rather than atrophy, takes place in the neurons in the inferior olivary nucleus. Prior to the invention of Magnetic Resonance Imaging (MRI), HOD was difficult to be detected, and a firm diagnosis could only be made at autopsy. We present a case of bilateral HOD following surgical excision of a cavernous hemangioma in the brainstem. The literature and imaging findings of this uncommon condition are reviewed.  相似文献   
79.
This paper reports the results of a series of 5 patients who underwent closure of persistent bronchopleural fistula using extrathoracic muscle flaps over a 6-year period. All patients had failed more conservative treatment. The surgeries were one- or two-stage procedures performed with the collaboration of cardiovascular and reconstructive surgical staffs. There were no associated mortalities. The muscle flaps utilized were the latissimus dorsi, serratus anterior, pectoralis major, pectoralis minor, and trapezius. The results have been encouraging and allowed the complete closure of the bronchopleural fistula in the majority of patients. The authors present the best management of this serious disease, as well as its pathophysiology and clinical aspects.  相似文献   
80.
Crafting a payment mechanism for hospitals that provides for the legitimate operating needs of efficient institutions is an enduring health policy dilemma. The Prospective Payment System used by Medicare and some other payers in the US has been criticized for not adjusting for differences in severity of illness within diagnosis-related groups (DRGs). Previous studies have examined the relationship between profitability and severity of illness at the hospital level. This study examines the relationships between severity of illness and cost, revenue, and profit at the patient level. Two measures of severity (disease stage and number of unrelated diseases) were significant predictors of cost per case, and often had better predictive power than DRGs. In most instances, payers did not compensate adequately for severity so that higher values for the severity variables resulted in financial losses for the hospital.  相似文献   
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