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141.
Stroke volume is a key determinate of cardiac output. It is affected by the preload, contractility and afterload of the myocardium. It is possible to gain insight into the right and left ventricular preload following the insertion of a central venous catheter and pulmonary artery catheter to measure central venous pressure and pulmonary capillary wedge pressure, respectively. Abnormal measurements can indicate a pathophysiological state and guide management.  相似文献   
142.
Despite having been long regarded as too toxic for adult patients, pediatric‐like regimens containing L‐asparaginase have resulted in improved outcomes for adults with acute lymphoblastic leukemia (ALL). To characterize the spectrum of toxicity of repeated doses of polyethylene glycolated‐asparaginase (PEG‐asp) in adults, we reviewed all doses (2000 IU/m2) administered as part of a pediatric‐inspired regimen in adult ALL at our center. Subjects aged 18–60 yr with ALL (n = 152, 69.1% male) contributed 522 dose cycles to the study. Hepatotoxicity was the most common adverse event: grades 3–4 transaminitis and hyperbilirubinemia occurred in 53.9% and 23.7% of subjects, respectively. Hepatotoxicity was reversible; no cases of fulminate hepatic failure were observed. Other toxicities affecting at least 5% of subjects were grades 3–4 triglyceridemia in 50.9%, hypofibrinogenemia (<100 mg/dL) in 47.9%, clinical pancreatitis in 12.6%, venous thromboembolism in 11.2%, allergic reaction in 7.2%, and any grade bleeding in 5.3%. PEG‐asp was always discontinued after grades 3–4 pancreatitis or allergic reaction. Otherwise, toxicities did not preclude administration of additional cycles of the drug. Our results suggest that repeated PEG‐asp dosing is safe in adults aged 18–60 yr, even after occurrence of a drug‐related toxicity.  相似文献   
143.
144.
Abstract

The authors review their lengthy experience in treating high grade osteosarcoma of the extremity. During the past 20 years many advances have been made in treating high grade osteosarcoma of the extremity. Twenty years ago, in spite of amputation, most patients with this tumor died, whereas today most are cured and amputation is avoided. These advances are mainly due to the development of effective adjuvant and neoadjuvant chemotherapy regimens. This review reports on the progress and controversies in the treatment of osteosarcoma.  相似文献   
145.
Acute pulmonary embolism (PE) is a major public health problem. It is the third most common cause of death in hospitalized patients. In the United States, there are up to 600,000 cases diagnosed per year with 100,000-180,000 acute PE-related deaths. Common risk factors include underlying genetic conditions, acquired conditions, and acquired hypercoagulable states. Acute PE increases the pulmonary vascular resistance and the load on the right ventricle (RV). Increased RV loading causes compensatory RV dilation, impaired contractility, tachycardia, and sympathetic activation. RV dilation and increased intramural pressure decrease diastolic coronary blood flow, leading to RV ischemia and myocardial necrosis. Ultimately, insufficient cardiac output from the RV causes left ventricular under-filling which results in systemic hypotension and cardiovascular collapse. Current prognostic stratification strategy separates acute PE into massive, submassive, and low-risk by presence or absence of sustained hypotension, RV dysfunction, and myocardial necrosis. Massive, submassive, and low-risk acute PE have mortality rates of 25%-65%, 3%, and <1%, respectively. Current PE management includes the use of anticoagulation alone, systemic thrombolysis, catheter-directed thrombolysis, and surgical embolectomy. This article will describe the current state of practice for catheter-directed thrombolysis and its role in the management of acute PE.  相似文献   
146.
We present a case of developmental venous anomaly associated with arteriovenous fistula supplied by a single arterial feeder adjacent to a large acute intracerebral hemorrhage. The arteriovenous fistula was successfully obliterated by superselective embolization while completely preserving the developmental venous anomaly. Two similar cases, including superselective angiographic findings, have been reported in the literature; however, we describe herein superselective angiographic findings in more detail and demonstrate the arteriovenous shunt more clearly than the previous reports. In addition, a literature review was performed to discuss the association of a developmental venous anomaly with vascular lesions.  相似文献   
147.
PurposeTo investigate and compare venous sac and feeding artery embolization (VFE) with feeding artery embolization (FAE) alone for treatment of pulmonary arteriovenous malformations (PAVMs), based on difference in outcomes in decrease of the size of the draining vein.Materials and MethodsTwenty-six patients (7 male and 19 female; median age [interquartile range], 58 years [46–65 years]) with 42 simple PAVMs treated with coil embolization between August 2005 and December 2018 were retrospectively evaluated. Twenty PAVMs were treated with FAE early in the study period and compared with 22 PAVMs treated with VFE later in the study period. Follow-up computed tomography images obtained 8–20 months after embolotherapy were used for outcome analysis. Data related to patient demographics; follow-up period; baseline diameters of the feeding artery, venous sac, and draining vein; draining vein diameter after treatment; and decrease in the size of the draining vein, including the number reaching a threshold of 70% decrease, were compared between the 2 groups.ResultsThe draining vein decreased in size by a median of 46.4% in the FAE group and 66.3% in the VFE group, and the difference between the 2 groups was statistically significant (P = .009). There were no significant differences in the other parameters.ConclusionsVFE leads to a greater decrease in the size of the draining vein than FAE, suggesting that VFE results in more complete occlusion than FAE for treatment of PAVMs.  相似文献   
148.
149.
This study was aimed at assessing the effects of urokinase (UK) in combination with ultrasound and microbubbles in in vitro and in vivo thrombolytic therapy for the treatment of deep vein thrombosis (DVT). Thrombi with formation times of 1, 3, 7, 14 and 21 d were used for thrombolysis. Forty-five adult mongrel dogs were used to evaluate thrombosis in vivo. Both in vitro and in vivo analyses revealed that UK?+?microbubbles had the best effect among the combinations. Thrombolysis <7 d was more effective at a thrombolysis rate of about 50%, but the thrombolytic effect of thrombi >7 d was poor at thrombolysis rates <30%. Ultrasound?+?UK significantly increased the thrombolysis rate of thrombi <7 d. These results suggest that the combination of ultrasound with microbubble contrast agents and UK may have a synergistic effect on thrombolysis.  相似文献   
150.
目的探讨磁共振静脉血氧水平依赖成像(VEN-BOLD)和时间飞跃法血管成像(TOF-MRA)对静脉畸形(CVM)的诊断价值。方法采用1.5T超导磁共振扫描仪对我院收治的13例CVM患者进行TOF-MRA和VEN-BOLD对比成像分析。结果 TOF-MRA原始轴位图像可显示全部13例CVM的引流静脉,并可进行最大密度投影重建(MIP)3D图像观察,但仅6例原始图像可显示稀少的髓静脉;而VEN-BOLD可清晰显示全部13例CVM的引流静脉及更多的髓静脉。结论 TOF-MRA可对CVM的引流静脉进行3D直观显示;而VEN-BOLD可清晰准确地显示CVM的引流静脉及髓静脉,二者结合可作为CVM诊断必要的补充序列。  相似文献   
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