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91.
Background Urogenital melanoma is a rare neoplasm with poor prognosis. Its management in the past involved radical vulvectomy and complete bilateral inguinofemoral lymphadenectomy. Sentinel lymph node biopsy is an accurate low-morbidity procedure when used in the context of cutaneous melanoma. However, prophylactic lymphadenectomy has not been shown to improve survival of melanoma patients. We wanted to determine the feasibility of sentinel lymph node biopsy in patients with female urogenital melanoma as a staging procedure. Methods Six patients with vulvar or vaginal melanomas underwent preoperative lymphatic mapping with99mTc-labeled sulfur colloid followed by sentinel lymphadenectomy. In addition, we reviewed the literature on the application of sentinel lymph node biopsy in urogenital tract melanomas. Results One or more sentinel nodes were identified in all six patients by lymphoscintigraphy. All patients underwent sentinel lymphadenectomy, except for one patient with a deep vaginal melanoma that drained to pelvic nodes. The five successful cases had unilateral drainage patterns. None of the sentinel lymph nodes excised had tumor invasion. Combined with five other patients from the published literature, the success rate of localizing sentinel lymph nodes in the patients with urogenital melanoma approaches 100%. Conclusions This experience, plus reports of a small number of patients from three similar studies, supports the impression that sentinel lymph node biopsy is feasible for vulvar and vaginal melanoma.  相似文献   
92.
Pseudoachalasia is an esophageal motor disorder usually associated with malignancy that has clinical, radiographic, and manometric findings that are often indistinguishable from primary achalasia. There are few reports examining the histologic features of the associated neoplasms and their relationship with the esophageal myenteric plexus. We studied the clinical and pathologic features of 13 cases of pseudoachalasia seen at our institution between 1979 and 1999. Detailed clinical and radiographic data were obtained from medical records. In all cases available histologic material was reviewed to confirm the presence and type of associated neoplasm. When possible, the relationship of the neoplasm to the esophageal myenteric plexus was examined. In selected cases immunohistochemical stains were performed to further evaluate this relationship. All patients had clinical, radiographic, and manometric features similar to primary achalasia. The cohort included seven men and six women, age range 24-79 years (median 61 years). Associated neoplasms included esophageal adenocarcinoma arising in Barrett's esophagus (n = 1), adenocarcinoma of the esophagogastric junction (n = 7), metastatic renal cell carcinoma to the esophagogastric junction (n = 1), breast adenocarcinoma (n = 1), pulmonary small cell carcinoma (n = 1), pleural malignant mesothelioma (n = 1), and mediastinal fibrosis (n = 1). The mechanism of pseudoachalasia was consistent with neoplastic infiltration of the esophageal myenteric plexus in 11 cases. Neoplastic cells surrounded myenteric ganglion cells, which appeared normal in number and morphology. In the patient with pulmonary small cell carcinoma, there was no evidence of neoplastic infiltration of the esophagogastric junction, and anti-ANNA-1 antibody was detected, suggesting a paraneoplastic syndrome. Tissue obtained at the time of esophagomyotomy revealed lymphocytic myenteric inflammation and marked depletion of ganglion cells identical to that seen in primary achalasia. The mechanism pseudoachalasia in the patient with breast adenocarcinoma is uncertain, as there was no evidence of direct involvement of the esophagogastric junction. In summary, we describe 13 cases of pseudoachalasia resulting in a clinical syndrome indistinguishable from primary achalasia. The most common mechanism is direct involvement of the esophageal myenteric plexus by neoplastic cells. Rarely, a distant neoplasm may cause this syndrome as a paraneoplastic process.  相似文献   
93.
Synovial sarcoma occurs predominantly in the paraarticular regions of the extremities. Synovial sarcoma of the mediastinum is an exceedingly rare neoplasm that has overlapping histologic and immunophenotypic features with other tumors in the differential diagnosis. We describe two cases. One is a 67-year-old patient who presented with chest pain and shortness of breath. Diagnostic imaging revealed a mediastinal mass extending over the cardiac apex. Histopathology, immunohistochemistry, and molecular genetic analysis confirmed the diagnosis of synovial sarcoma. The patient underwent surgical resection and postoperative radiation therapy. He is alive and well 18 months after diagnosis. This case illustrates the importance of proper procurement of frozen tissue for molecular genetic analysis for the identification of the t(X;18), characteristic of synovial sarcoma. Detection of this translocation is of paramount importance to confirm this diagnosis, particularly when this neoplasm arises in atypical locations outside the extremities.  相似文献   
94.
Experimental investigations of single mild brain injury (SMI) show relatively little resultant cognitive impairment. However, repeated mild brain injuries (RMI), as those sustained by athletes (e.g., football, hockey, and soccer players) may have cumulative effects on cognitive performance and neuropathology. Numerous clinical studies show persistent, latent, and long-term consequences of RMI, unlike the episodic nature of SMI. The nature of repeated traumatic brain injury (TBI) introduces confounding factors in invasive and even semiinvasive animal models of brain injury (e.g., scar formation). Thus, the present study characterizes SMI and RMI in a noninvasive mouse weight drop model and the cumulative effects of RMI on cognitive performance. Investigation of drop masses and drop distances revealed masses of 50, 100, and 150 g dropped from 40 cm resulted in 0% mortality, no skull fracture, and no difference in acute neurological assessment following sham injury, SMI, or RMI. Cumulative effects of RMI were examined following four mild brain injuries 24 h apart induced by 50-, 100-, or 150-g masses dropped from 40 cm through histological measures, mean arterial pressure, and measures of complex/spatial learning. RMI produced no overt cell death within the cortex or hippocampus, no evidence of blood-brain barrier compromise, and no significant change in mean arterial pressure. Following testing in the Morris water maze (MWM) on days 7-11 after initial injury, mice in the RMI 100-g and RMI 150-g groups had significantly longer MWM goal latencies compared to sham, SMI 150-g, and RMI 50-groups. Additionally, the evident cognitive deficit manifested in the absence of observed cell death. This is the first study to show complex/spatial learning deficits following RMI, similar to the visual/spatial perception and planning deficits observed in clinical studies.  相似文献   
95.
Summary Background. In previous studies, it has been shown that intravenous lactate therapy can improve brain neurochemistry, adenosine triphosphate (ATP) generation and outcome after traumatic brain injury (TBI) in rats. In this study, we examined: (1) four L-lactate concentrations to determine the optimal therapeutic dose post TBI in terms of cognitive function; (2) ATP production after TBI for the L-lactate concentration found to be the optimal dose; (3) the possible production of lactic acidosis with the highest L-lactate concentration tested. Methods. Thirty minutes following a fluid percussion injury (FPI) over the left cerebral hemisphere, the animals received an intravenous infusion of 10, 28, 100, or 280 mM L-lactate (n = 10 for each group) for 3 h at a rate of 0.65 ml/h. Shams and control injured animals received a saline infusion. At 11–15 days post injury, cognitive deficits were examined using the Morris Water Maze (MWM) test. Three groups of rats were used for ATP analysis: shams, injured + saline infusion, and injury + the optimal lactate dose as determined by the MWM (n = 4/group). Additionally, a group receiving 280 mM L-lactate (n = 5) and one receiving a saline infusion (n = 3) were monitored for arterial blood variables and blood pressures. Findings. In the MWM test, only the 100 mM L-lactate-treated injured animals showed a significant reduction in cognitive deficits when compared to saline-treated injured animals (p ≤ 0.05). In the ATP study, injured animals without treatment had a 53% reduction in ATP level in the ipsilateral cortex, while animals with 100 mM lactate treatment had a 28% reduction. (p ≤ 0.05). No lactic acidosis was induced by the intravenous infusion of 280 mM L-lactate. Conclusions. This study indicates that the intravenous infusion of 100 mM L-lactate provided the optimal concentration of the substrate to ameliorate cognitive impairment, probably via the regeneration of ATP following TBI in rats.  相似文献   
96.
Atherosclerosis accounts for most peripheral arterial occlusive disease (PAD). Although many of the risk factors for atherosclerotic coronary artery disease (CAD) such as hyperlipidemia have been identified as risk factors for peripheral arterial disease, strong evidence is lacking that risk factor modification is effective in halting progression or improving outcomes. A better understanding is needed regarding the clinical and pathophysiologic responses to risk factor modification. This review describes current advances in the medical management for PAD including lipid modification antiplatelet therapy, angiotensin-converting enzyme (ACE) inhibitors, beta-blockers, exercise, and endovascular intervention. In addition, we discuss our active ELIMIT Trial (Effect of Lipid Modification on Peripheral Arterial Disease after Endovascular Intervention). We test the hypothesis that an aggressive regimen of serum lipid modification will inhibit the progression of atherosclerosis in femoral arteries and reduce the incidence of restenosis of femoral arteries following endovascular stenting by decreasing thrombosis and inflammation. This study will provide a novel strategy for retarding or preventing progression of atherosclerosis and re-stenosis of peripheral arterial disease following arterial revascularization procedures. Importantly, our magnetic resonance imaging studies will provide quantitative data on the vascular lesions in PAD. These studies will advance our understanding of the molecular mechanisms of inflammation and thrombosis associated with aggressive lipid modification. This work was presented at the Molecular Surgeon Symposium on Vascular Injury, Repair and Remodeling at the Baylor College of Medicine, Houston, Texas, May 15 and 16, 2006. The symposium was supported by a grant from the National Institutes of Health National Institute of Health (to C. Chen: R13 HL0836500).  相似文献   
97.
Pulmonary sequestration is a form of bronchopulmonary-foregut malformation that is treated with surgical resection, either via a thoracotomy or the thoracoscopic approach. Apical extralobar pulmonary sequestrations are rare. We report a case of an apical pulmonary sequestration in an infant that was amenable to thoracoscopic resection. An 8-month-old girl, weighing 10.3 kg, with a left apical extralobar pulmonary sequestration underwent thoracoscopic resection. The pulmonary sequestration was identified and dissected free from surrounding tissue. The vascular peduncle was secured with an endo-GIA loaded with 2-mm vascular staples. The infant was discharged on postoperative day two without complications. In spite of the patient's small size and the apical nature of the sequestration, the operation was easily performed via a thoracoscopic approach. Thoracoscopic resection of an apical extrapulmonary sequestration in a small infant is feasible and may minimize the morbidity of this procedure.  相似文献   
98.
99.
PURPOSE: The purpose of this study was to determine the magnitude of changes in cardiac output (Qc), stroke volume (SV), and arterial-mixed venous oxygen difference (a-vO2 diff) during submaximal exercise following a 20-wk endurance training program, with the primary focus on identifying differences in response by race, sex, and age. METHODS: The participants in this study (N = 631) were healthy and previously sedentary men (N = 277) and women (N = 354) of varying age (17-65 yr) and race (blacks, N = 217; whites, N = 414) who had completed the HERITAGE Family Study protocol. After baseline measurements, participants trained on cycle ergometers 3 d x wk(-1) for a total of 60 exercise sessions starting at the HR associated with 55% of maximal oxygen uptake (VO2max) for 30 min/session and building to the HR associated with 75% of VO2max for 50 min/session, which was maintained during the last 6 wk. HR, Qc (CO2 rebreathing), and SV (Qc/HR) were determined in duplicate at 50 W and at 60% of VO2max on two different days both before and after training. RESULTS: After training, there were significant decreases in HR and Qc, and significant increases in SV and a-vO2 diff at 50 W (except for no change in a-vO2 diff in black men). The changes in HR differed by sex and age, and the changes in SV, Qc, and a-vO2 diff differed by race. Qc decreased by 0.6 L x min(-1) at 50 W for the total sample, consistent with the decrease in VO2 at this power output. At 60% of VO2max HR decreased, and SV, Q, and a-VO2 diff increased. There were small differences in response by sex (HR and SV), race (HR), and age (HR and Qc). CONCLUSION: It is concluded that the cardiovascular systems of men and women, blacks and whites, and younger and older subjects are not limited in their ability to adapt to endurance training.  相似文献   
100.
OBJECTIVE: Because chylothorax complicating thoracic surgery is difficult to diagnose and failure of nonoperative management necessitates further surgery, we critically evaluated an evolving percutaneous strategy for diagnosing and treating chylothorax. METHODS: After thoracic surgery, 37 patients with a clinical diagnosis of chylothorax were referred for lymphangiography for definitive diagnosis and percutaneous treatment. Successful localization of the cisterna chyli by lymphangiogram facilitated percutaneous cannulation of the thoracic duct and its embolization. In patients in whom cannulation was not possible, the thoracic duct was percutaneously disrupted. RESULTS: Diagnosis: Lymphangiography was successful in 36 of the 37 patients (97%). Contrast extravasation, confirming clinical diagnosis, was present in 21 of the 36 (58%). Management: Twenty-one of 36 patients underwent 22 lymphangiographically directed percutaneous interventions: 12 embolizations and 10 disruptions. Mortality was zero, with two manageable complications. Patients without percutaneous intervention were discharged a median of 7 days (range 4-58) after first lymphangiography, 8 days (range 2-19) after percutaneous embolization, and 19 days (range 6-48) after first disruption. Eight patients had nine subsequent reoperations for chylothorax, two with negative lymphangiograms; no embolization patient required reoperation. CONCLUSIONS: There is a discrepancy between the clinical diagnosis of chylothorax after thoracic surgery and the presumed gold standard of diagnosis, contrast extravasation at lymphangiogram. Percutaneous treatment by thoracic duct embolization or disruption is safe and may obviate reoperation, but embolization of the thoracic duct is preferable to its disruption.  相似文献   
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