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81.
Reperfusion injury has been one of the serious problems in cardiac surgery and medicine. We report a novel method of myocardial protection. Eight Sprague-Dawley rats, group A, were administrated green tea polyphenol orally. Eight other rats, group B, received no medication. Isolated hearts were perfused with a Langendorff's apparatus, and reperfused after 90min arrest. The left ventricular (LV) function, size, weight and the oxidative stress spaciotemporal analysis were performed. The LV size in group B became enlarged by 1.8+/-0.12 (mean+/-SD), but in group A, the LV enlarged only 1.1+/-0.08 times. The heart weight ratio was lighter (1.35+/-0.05) in group A than in group B (1.49+/-0.03, P<0.05). The LV end-systolic pressure volume relationship remained higher in group A. Oxidative stress as shown by 8-hydroxy-2'-deoxyguanosine was lower in group A (81.5+/-11.6) than in group B (226.9+/-35.6, P<0.0001). Polyphenol labeled FITC was located in the cell membrane of cardiomyocite. Polyphenol can protect a heart from oxidative stress, and maintain good LV function after ischemic arrest and reperfusion. This pre-treatment by polyphenol may add further benefit to current treatments of myocardial protection.  相似文献   
82.
We reviewed the surgical statistics of the Department of Urology, Isesaki Municipal Hospital between June 1998 and May 2003. A total of 1940 surgeries were performed. These consisted of 399 surgeries on the kidney, adrenal, and pelvis, 212 on the ureter, 433 on the bladder, 256 on the prostate, 149 on the urethra and the penis, 192 on the scrotum, 255 on the arteriovenous fistula and CAPD. In September 2003, a screening program for prostate cancer was started, and the number of prostate biopsies and total prostatectomies increased. As the adaptation of many procedures to laparoscopy expanded, the number of laparoscopic surgeries increased.  相似文献   
83.
Objectives: To report a novel cell therapy using autologous adipose tissue‐derived regenerative cells for male stress urinary incontinence caused by urethral sphincteric deficiency, and the outcomes in the initial cases undergoing periurethral injection of adipose tissue‐derived regenerative cells. Methods: Three patients with moderate stress incontinence after radical prostatectomy and holmium laser enucleation of the prostate were enrolled. Adipose tissue‐derived regenerative cells were isolated from the abdominal adipose tissue by using the Celution system. Subsequently, the isolated adipose tissue‐derived regenerative cells, and a mixture of adipose tissue‐derived regenerative cells and adipose tissue were transurethrally injected into the rhabdosphincter and submucosal space of the urethra, respectively. Short‐term outcomes during a 6‐month follow up were assessed by a 24‐h pad test, a validated patient questionnaire, urethral pressure profile, transrectal ultrasonography and magnetic resonance imaging. Results: Urinary incontinence progressively improved after 2 weeks of injection up to 6 months in terms of decreased leakage volume, decreased frequency and amount of incontinence, and improved quality of life. Both maximum urethral closing pressure and functional profile length increased. Magnetic resonance imaging suggested a sustained presence of the injected adipose tissue. Enhanced ultrasonography showed a progressive increase in the blood flow to the injected area. No significant adverse events were observed peri‐ and postoperatively. Conclusion: These preliminary findings suggest that periurethral injection of the autologous adipose tissue‐derived regenerative cells is a safe and feasible treatment modality for male stress urinary incontinence.  相似文献   
84.
Ogino M  Nagumo M  Nakagawa T  Nakatsukasa M  Murase I 《Neurosurgery》2003,53(2):444-7; discussion 447
OBJECTIVE AND IMPORTANCE: We successfully treated a patient with stenosis of the left subclavian artery, complicated by bilateral common carotid artery occlusion, via axilloaxillary bypass surgery. CLINICAL PRESENTATION: A 67-year-old patient with a history of hypertension and cerebral infarction underwent neck irradiation for treatment of a vocal cord tumor. Three months later, he began to experience transient tetraparesis several times per day. The blood pressure measurements for his right and left arms were different. Supratentorial blood flow was markedly low. The common carotid arteries were bilaterally occluded, and the right vertebral artery was hypoplastic. Therefore, only the left vertebral artery contributed to the patient's cerebral circulation; his left subclavian artery was severely stenotic. INTERVENTION: The patient underwent axilloaxillary bypass surgery because the procedure avoids thoracotomy or sternotomy, manipulation of the carotid artery, and interruption of the vertebral artery blood flow. The patient has been free of symptoms for more than 5 years. CONCLUSION: Neurosurgeons should be aware that extra-anatomic bypass surgery is an effective treatment option for selected patients with cerebral ischemia.  相似文献   
85.
Purpose  This study was undertaken to evaluate the changes in the radiopacity and mechanics of polymethylmethacrylate (PMMA) bone cement with the addition of barium. Materials and methods  Barium sulfate powder was added to a PMMA bone cement with an initial 10% barium concentration. The changes in radiopacity and strength were evaluated by testing cement blocks containing four barium concentrations (10%, 20%, 30%, 40%). Radiopacity was evaluated by measuring the computed tomography (CT) values of the bone cement, and strength was evaluated by compressive, three-point bending, and impact load tests. Results  CT values increased in proportion to the barium concentration. The compressive load test showed that cement with a 40% barium concentration was significantly more fragile than cement with lower barium concentrations. The three-point bending load test showed that the cement became more fragile in proportion to the barium concentration. The impact load test showed that cement with 30% and 40% barium concentrations was significantly more fragile than cement with 10% and 20% barium concentrations. Conclusion  Radiopacity is increased and strength is reduced by adding increasing concentrations of barium powder to bone cement. The results of the present study suggest that adding barium permits the radiopacity and strength of bone cement to be adjusted in clinical practice.  相似文献   
86.
Background. This study was designed to assess the influence of coronary endothelial function and the serial changes of dual myocardial single photon emission computed tomography (SPECT) imaging in transient left ventricular (LV) apical ballooning. Methods and Results. We evaluated 35 consecutive patients (8 men and 27 women; mean age, 71 ±13 years) with transient LV apical ballooning. All patients underwent coronary angiography with acetylcholine provocation 1 month after onset. Iodine 123 β-methyl-p-iodophenyl-pentadecanoic acid (BMIPP) and thallium 201 dual myocardial SPECT was serially performed on day 1 of admission and 1 month and 6 months later. In 8 of 35 patients (23%), epicardial coronary spasm was induced by acetylcholine infusion. At the peak acetylcholine dose (100 μg), diffuse coronary vasoconstriction developed in 19 of 35 patients (54%). Of 19 patients, 13 had diffuse coronary vasoconstriction with chest pain and ST-segment depression. The total defect score of I-123 BMIPP and Tl-201 SPECT showed marked perfusion-fatty acid metabolic mismatches (13.7±3.6 vs 8.7±2.3, P<.001) at the LV apex during the acute phase but few mismatched areas (2.1±1.1 vs 1.5±1.4, P = not significant) at 6 months. Conclusions. Transient LV apical ballooning might be caused by stress-induced coronary epicardial spasm or endothelial dysfunction, resulting in myocardial stunning.  相似文献   
87.
OBJECTIVES: The purpose of this study was to investigate how the inflow cannulation site of the left ventricular assist system with a centrifugal pump would influence cardiac function on failing heart models. METHODS: In 10 sheep, a left ventricular assist system was instituted by an outflow cannula in the descending aorta, two inflow cannulas in the left atrium and the left ventricle, and connecting those cannulas to a magnetically suspended centrifugal pump. A conductance catheter and a tipped micromanometer for monitoring the pressure-volume loop were also inserted into the left ventricle. Myocardial oxygen consumption was directly measured. Heart failure was induced by injection of microspheres into the left main coronary artery. The assist rate was varied from 0% to 100% at each inflow cannulation site. RESULTS: The pump flow with left ventricular cannulation increased during the systolic phase and decreased during the diastolic phase, whereas it was constant with left atrial cannulation. Ejection fraction with left atrial cannulation decreased as the assist rate increased, whereas that with left ventricular cannulation was maintained up to 75% assist. The external work with left atrial cannulation decreased gradually as the assist rate increased, whereas the external work with left ventricular cannulation did not decrease until the assist rate reached 75%. The myocardial oxygen consumption in both cannulations decreased proportionally as the assist rate increased; they were significantly less with left ventricular cannulation at the 100% assist rate than with left atrial cannulation. CONCLUSION: Left ventricular cannulation during left ventricular assistance maintains ejection fraction and effectively reduces oxygen consumption.  相似文献   
88.
We experienced a case of a huge hemangioma occupying the oropharyngeal space in an 11-year-old child. Although urgent surgical tracheostomy under local anesthesia was suggested initially, medical interview and findings of computerized tomography and fiberoptic laryngoscopy revealed that the airway of the patient was relatively stable when she was in the semi-left decubitus position. General anesthetic induction would have had potential risks of airway obstruction. Thus, after placing the patient in the semi-left decubutus position, we chose semi-awake induction to secure the airway. With a small dose of fentanyl, we accomplished orotracheal intubation. In this report, we discuss the importance of referring to an airway management algorithm when encountering a difficult airway.  相似文献   
89.

Purpose

To establish the most effective methods of postoperative surveillance to detect early recurrence of lung adenocarcinoma.

Methods

The subjects of this retrospective study were 485 patients with p-stage I–III lung adenocarcinoma, who underwent postoperative surveillance. We examined the sites and detection modes of recurrence and calculated the recurrence-free probabilities. Patients with stage I disease were divided into low- and high-risk recurrence groups using a risk score calculated by assigning points proportional to risk factor regression coefficients.

Results

Of the 112 patients with recurrence, 86 had intrathoracic recurrence. Routine computed tomography (CT) revealed recurrence in 60 patients. The recurrence-free probability curves showed that 95% of recurrences were identified within the first 4 years after resection in patients with stage II/III disease. In patients with stage I disease, the predictors of recurrence included male sex, positive pleural lavage cytology, moderate-to-poor differentiation, and visceral pleural invasion. Postoperative recurrences were detected throughout the follow-up period in the high-risk group.

Conclusions

Routine chest CT plays an important role in the postoperative surveillance of lung adenocarcinoma. We recommend intensive follow-up during the early post-resection period for patients with advanced stage disease and long-term follow-up for high-risk patients with stage I disease.
  相似文献   
90.

Purpose

The clinical implications of mucinous components in rectal tumors, especially with regard to the efficacy of neoadjuvant chemoradiotherapy, remain unclear.

Methods

One hundred and thirty rectal cancer patients who received curative resection after neoadjuvant chemoradiotherapy were retrospectively reviewed. Patients were classified into 3 groups according to the proportion of extracellular mucin: low (<5 %), moderate (5–25 %), and high (>25 %).

Results

There were 82 (63.1 %), 26 (20.0 %), and 22 (16.9 %) patients in the low, moderate, and high mucin groups, respectively. Patients with a high mucinous tumor component were significantly more likely to have an advanced tumor stage (p = 0.010) and a shorter disease-free (p = 0.002) and distant recurrence-free survivals (p < 0.001), whereas the mucinous tumor component showed no correlation with local recurrence (p = 0.101). A high mucinous component was also an independent predictive factor for a shorter disease-free survival (p = 0.041, hazard ratio = 2.56) and distant recurrence-free survival (p = 0.001, hazard ratio = 5.74) according to a multivariate analysis.

Conclusions

Because the mucinous components showed little correlation with local recurrence, mucinous cancer should not be a determining factor for chemoradiotherapy. However, the frequent occurrence of metachronous distant metastasis among patients with a high mucin component makes this a possible indicator for more robust postoperative adjuvant treatment and close surveillance of recurrence.
  相似文献   
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