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101.
PURPOSE: To determine whether a routine postoperative chest x-ray is required following uneventful laparoscopic nephrectomy to rule out pneumothorax. METHODS: From June 1999 to May 2003, 308 laparoscopic nephrectomy cases were performed by 5 different surgeons. This consisted of 121 radical nephrectomies, 106 donor nephrectomies, 29 simple nephrectomies, 29 partial nephrectomies, and 23 nephroureterectomies. Of the 308 procedures, 186 postoperative chest x-ray s were obtained in the recovery room: 183 routinely and 3 for known intraoperative diaphragmatic injuries. Routine chest x-rays were not obtained in 122 cases due to the individual surgeon's preference. Of these 122 patients, 15 underwent chest x-ray performed while hospitalized secondary to pulmonary issues or fever. RESULTS: Of the 308 cases, 4 pneumothoraces were identified on chest x-ray. Three were identified in the patients who had intraoperative identification of diaphragmatic injury. The fourth pneumothorax was identified in a patient who did not have a routine postoperative chest x-ray but did have a chest x-ray obtained due to postoperative shoulder pain. The pneumothorax in this patient resolved spontaneously. No incidental findings existed of pneumothorax in any patient who underwent routine postoperative chest x-ray. CONCLUSION: In our series, a pneumothorax was identified either intraoperatively or based on postoperative clinical findings. None of the 183 routine postoperative chest x-rays changed patient management. Routine postoperative chest x-ray is not necessary in uncomplicated laparoscopic nephrectomy.  相似文献   
102.
Background BMS-747158-02 is a novel fluorine 18-labeled pyridazinone derivative designed for cardiac imaging. The uptake and retention mechanisms of F-18 BMS-747158-02 in cardiac myocytes were studied in vitro, and the biodistribution of F-18 BMS-747158-02 was studied in vivo in mice. Methods and Results Fluorine 19 BMS-747158-01 inhibited mitochondrial complex I (MC-I) in bovine heart submitochondrial particles with an IC50 of 16.6±3 nmol/L that was comparable to the reference inhibitors of MC-1, rotenone, pyridaben, and deguelin (IC50 of 18.2±6.7 nmol/L, 19.8±2.6 nmol/L, and 23.1±1.5 nmol/L, respectively). F-18 BMS-747158-02 had high uptake in monolayers of neonatal rat cardiomyocytes (10.3%±0.7% of incubated drug at 60 minutes) that was inhibited by 200 nmol/L of rotenone (91%±2%) and deguelin (89%±3%). In contrast, an inactive pyridaben analog, P-0 (IC50 value>4 μmol/L in MC-1 assay), did not inhibit the binding of F-18 BMS-747158-02 in cardiomyocytes. Uptake and washout kinetics for F-18 BMS-747158-02 in rat cardiomyocytes indicated that the time to half-maximal (t1/2) uptake was very rapid (approximately 35 seconds), and washout t1/2 for efflux of F-18 BMS-747158-02 was greater than 120 minutes. In vivo biodistribution studies in mice showed that F-18 BMS-747158-02 had substatial myocardial uptake (9.5%±0.5% of injected dose per gram) at 60 minutes and heart-to-lung and heart-to-liver ratios of 14.1±2.5 and 8.3±0.5, respectively. Positron emission tomography imaging in the mouse allowed clear cardiac visualization and demonstrated sustained myocardial uptake through 55 minutes. Conclusions F-18 BMS-747158-02 is a novel positron emission tomography cardiac tracer targeting MC-I in cardiomyocytes with rapid uptake and slow washout. These characteristics allow fast and sustained accumulation in the heart.  相似文献   
103.
This study was undertaken to evaluate changes in relative (99m)Tc-hydrazinonicotinamide (HYNIC)-annexin V tumor uptake over time in patients undergoing chemotherapeutic treatment at baseline and at 5-7 h and 40-44 h after treatment initiation. Imaging results are related to clinical outcomes, as assessed with response evaluation criteria in solid tumors (RECIST). METHODS: We prospectively included 20 patients (11 men and 9 women; mean age, 59.8 y; range, 22-75 y) scheduled for chemotherapy (n = 19) or bisphosphonate treatment (n = 1). Curable disease was present in 5 patients. The other patients had metastatic disease and were treated in a palliative setting. Three of the 20 enrolled patients were excluded from analysis: 1 patient ultimately refused the proposed chemotherapy treatment; because of difficulties with the labeling procedure, 1 patient did not receive a pretreatment scan; and 1 patient presented with an allergic reaction (rash and nausea) to the (99m)Tc-HYNIC-annexin V formulation. The remaining 17 patients underwent 3 scintigraphic scans with (99m)Tc-HYNIC-annexin V: before treatment and 5-7 h and 40-44 h after treatment initiation. The tumor response was evaluated with RECIST and related to observed changes in the ratios of tumor activity to background activity for the largest known lesion; values exceeding 25% the baseline value on either the 5- to 7-h scan or the 40- to 44-h scan were considered significant. RESULTS: With the proposed sequential imaging protocol and a 25% change threshold, responders to treatment could be separated from nonresponders with a 94% accuracy (16/17 patients). CONCLUSION: Sequential (99m)Tc-HYNIC-annexin V imaging may allow for assessment of the response to chemotherapy within 3 d after treatment initiation.  相似文献   
104.
OBJECTIVES: To determine electrocardiogram (ECG) predictors of positive cardiac markers and short-term adverse cardiac events in an undifferentiated chest pain population presenting to emergency departments (EDs). The authors hypothesized that specific ECG findings, other than those previously identified in higher-risk populations, would be predictive of cardiac outcomes and positive cardiac markers. METHODS: This study used data from a prospectively collected, retrospectively analyzed Internet-based data registry of undifferentiated chest pain patients (i*trACS). Logistic regression modeling was performed to determine the ECG findings that were predictive of 1) positive cardiac markers and 2) short-term adverse cardiac events. RESULTS: ST-segment elevation (STE), ST-segment depression (STD), pathological Q-waves (PQW), and T-wave inversion were associated with increased odds of percutaneous coronary intervention or catheterization, myocardial infarction, or coronary artery bypass grafting. The odds of creatine kinase-MB (CK-MB) measuring positive were increased if STE, STD, or PQW were present [odds ratio (OR) 2.495, 2.582, and 1.295, respectively]. A right bundle branch block tended to decrease the odds of CK-MB measuring positive (OR 0.658). A similar pattern of results was observed for troponin I (OR 3.608 for STE, 3.72 for STD, 1.538 for PQW). Troponin T showed an increased odds of measuring positive if any of STE, STD, left bundle branch block, or T-wave inversion were evident (OR 2.313, 2.816, 1.80, and 1.449, respectively). CONCLUSIONS: Initial ECG criteria can be used to predict short-term cardiac outcomes and positive cardiac markers. These findings can be important aids in the risk-stratification and aggressive treatment regimens of chest pain patients presenting to EDs.  相似文献   
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106.
This review tries to summarize the efforts over the past 20 years to construct a tissue-engineered trachea. After illustrating the main technical bottlenecks faced nowadays, we discuss what might be the solutions to these bottlenecks. You may find out why the focus in this research field shifts dramatically from the construction of a tubular cartilage tissue to reepithelialization and revascularization of the prosthesis. In the end we propose a novel concept of 'in vivo bioreactor', defined as the design of a perfusion system inside the scaffold, and explain its potential application in the construction of a tissue-engineered trachea.  相似文献   
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Noninsulin dependent diabetes (type II diabetes) is a chronic disease characterized by hyperglycemia. Clients can generally be controlled by diet and exercise or a combination of diet, exercise, and oral hypoglycemic agents. When this therapy is not effective in controlling the hyperglycemia, the health care provider must choose to initiate insulin therapy. Outpatient initiation of insulin is an alternative to hospitalization in the type II diabetic client. Clinical guidelines for the initiation of insulin on an outpatient basis and management of the diabetic client are presented.  相似文献   
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