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51.
We have already reported that heart transplantation and left ventricular assist system (LVAS) are the useful surgical treatments for severe heart failure. However, these treatments have several problems such as donor limitation and complications and a novel strategy is desired. The autologous myoblast sheets attenuated the cardiac remodeling in the rat infarcted myocardium and dilated cardiomyopathy hamsters, leading to the improvement of cardiac performance. In this study, we will report the present results of heart transplantation and LVAS and also, report the development of porcine autologous myoblast sheets and hypothesized that autologous myoblast sheets regenerate the porcine infracted myocardium for clinical application. Skeletal myoblast (SM) isolated from leg muscle were cultured and detached from the dishes as single monolayer cell-sheet (tissue) at 20 degrees C using temperature-responsive culture dishes. Echocardiography demonstrated that cardiac systolic performance was significantly improved in SM group 4 weeks after operation rather than the control group. Both diastolic dysfunction and regional delayed relaxation in association with regional systolic function were recovered in the SM group, while the control group were not. Histologically, anterior wall was significantly recovered and dilatation of left ventricle was well attenuated in the SM group, while not in the other groups. SM-sheet implantation improved cardiac function by attenuating the cardiac remodeling and metabolic recovery in the impaired myocardium in the porcine ischemic myocardium, suggesting a promising strategy for clinical myocardial regeneration therapy.  相似文献   
52.
53.
We report a 64-year-old woman treated with surgical intervention for late-onset chylothorax following a pleuropneumonectomy. The patient underwent an extrapleural pneumonectomy for diffuse malignant mesothelioma and was uneventfully discharged on postoperative day 29. Pleural effusion aspirated on postoperative day 9 was dark red. A chest roentgenogram taken at our outpatient clinic revealed a mediastinal shift on postoperative day 56. No bacterial infection was found in the milky effusion. We made a diagnosis of postoperative late-onset chylothorax based on the laboratory data obtained from tests of the pleural fluid. A repeat thoracotomy to ligate the lymphatic duct was performed because conservative management with chest tube drainage and no oral feeding was unsuccessful. The patient was discharged after the operation with a good clinical course.  相似文献   
54.
55.

Purpose

Preventing a recurrence of Crohn’s disease is a problem that remains to be solved. We evaluated the impact of using infliximab as a postoperative therapy on preventing the surgical recurrence of Crohn’s disease.

Methods

We performed a pair-matched study comparing 100 patients who had received postoperative infliximab maintenance therapy with those who had not between 1995 and 2010. The patients were matched by gender, Vienna classification and age at the time of the operation. Crohn’s disease-related reoperation was evaluated as surgical recurrence.

Results

In the postoperative infliximab maintenance therapy group, infliximab was administrated within 8 weeks after the operation. The median follow-up period was 36 months in the postoperative infliximab maintenance therapy group and 51 months in the control group. Surgical recurrences were recognized in 37 patients (three in the postoperative infliximab maintenance therapy group and 34 in the control group). A univariate analysis by the Kaplan–Meier method identified a body mass index >18 at the time of the operation (HR 0.19, p = 0.01) and postoperative infliximab maintenance therapy (HR 0.22, p = 0.0022) as factors related to the reduction of surgical recurrence. The multivariate analysis revealed that postoperative infliximab maintenance therapy was the only significant factor preventing surgical recurrence.

Conclusion

Postoperative infliximab maintenance therapy for Crohn’s disease prevents surgical recurrence, at least within 3 years after the operation.  相似文献   
56.
A 41-year-old man presented with progressive worsening of postural headache. Computed tomography (CT) showed bilateral subdural hematomas without prior history of trauma. The diagnosis was spontaneous intracranial hypotension (SIH). Conservative treatment with oral steroids failed to prevent gradual deterioration of the patient's consciousness. CT myelography revealed massive cerebrospinal fluid (CSF) leakage between the C-1 and C-2 levels. The leak was repaired surgically via a laminectomy. A cyst, thought to be a meningeal cyst, was discovered adjacent to the right C-2 nerve root, and CSF was seen seeping out from around the cyst after a Valsalva maneuver. The presumed dural defect of the cyst was sealed by packing with muscle fragments and fibrin glue. The symptoms disappeared soon after surgery. He was discharged 1 month after surgery without deficits. Most SIH cases are benign and can be managed conservatively, or by the epidural blood patch method. Surgery is more invasive than the epidural blood patch method, but should be performed in patients with a high cervical lesion and massive CSF leakage.  相似文献   
57.
BACKGROUND: Hemodialysis patients have advanced arterial wall stiffening as shown by increased aortic pulse wave velocity (PWV), an independent predictor of cardiovascular mortality. We compared aortic PWV of uremic patients before starting hemodialysis treatment with that of patients on maintenance hemodialysis. METHODS: The subjects were 71 patients with end-stage renal disease (ESRD) before starting hemodialysis (predialysis group), 144 patients on maintenance hemodialysis, and 140 healthy control subjects. These three groups were all nondiabetic and comparable in age and gender. RESULTS: The hemodialysis group had greater aortic PWV than the healthy subjects, and the predialysis patients showed a still higher value than the hemodialysis group. Multiple regression analysis in the total subjects revealed that the presence of renal failure was significantly associated with increased aortic PWV independent of age, gender, blood pressure, body mass index, smoking, high-density lipoprotein (HDL) and nonhigh-density lipoprotein (non-HDL) cholesterol levels. In contrast, hemodialysis was associated with decreased aortic PWV independent of renal failure and the other factors. Further analyses in the combined uremic patients again indicated the favorable impact of hemodialysis on aortic PWV independent of the classical risk factors, use of antihypertensive medications, including angiotensin-converting enzyme inhibitors and calcium channel blockers, hematocrit, serum calcium, phosphorus, parathyroid hormone levels, and the use of calcium carbonate. Insulin resistance using homeostasis model assessment (HOMA-IR) was associated with increased aortic PWV. CONCLUSION: Aortic stiffening was present in uremic patients before starting hemodialysis treatment and no adverse effect of hemodialysis was observed, suggesting the important roles of renal failure and/or metabolic alterations secondary to renal failure in arterial stiffness in patients with uremia.  相似文献   
58.
Fast MR imaging in obstetrics.   总被引:8,自引:0,他引:8  
Ultrasonography (US) is the initial imaging modality of choice for evaluation of patients in obstetrics. However, the results of US are not always sufficient. Magnetic resonance (MR) imaging, which uses no ionizing radiation, may be an ideal method for further evaluation. Although MR imaging is not recommended during the first trimester and use of contrast material is not recommended in pregnant patients, fast MR imaging is useful in various obstetric settings and can provide more specific information with excellent tissue contrast and multiplanar views. In pregnant patients with acute conditions, various diseases (eg, red degeneration of a uterine leiomyoma) may be diagnosed. MR imaging allows characterization of pelvic masses discovered during pregnancy and diagnosis of postpartum complications (eg, abscess, hematoma, ovarian vein thrombosis). In pregnant patients with hydronephrosis, MR urography can demonstrate the site of obstruction and the cause (eg, a ureteral stone). MR pelvimetry may be beneficial in cases of breech presentation. Contrast material-enhanced dynamic MR imaging allows one to evaluate the vascularity of a placental polyp, detect the viable component of a gestational trophoblastic tumor, and diagnose a uterine arteriovenous malformation. MR imaging enables diagnosis of rare forms of ectopic pregnancy and early diagnosis of ectopic pregnancy.  相似文献   
59.
Many approaches for resection of the superior mediastinal tumors have been reported. We introduce an approach, which we call the cervical anterior approach. This approach is only cervical and does not require a sternotomy. Merits of this approach include the ability to remove the tumor without opening the mediastinal or parietal pleura, as well as obviating draining the thoracic cavity. The tumor is also directly visible, and the surgeon can avoid injury to the great vessels. This approach is recommended when the tumor is located superior to the third thoracic vertebra level, when it borders the great vessels, and when it does not border the trunk of the brachial plexus or nerve root. This approach is easy and safe for surgical procedures.  相似文献   
60.
BACKGROUND: Carbon dioxide is an important vasodilator of cerebral blood vessels. Cerebral vasodilation mediated by adenosine triphosphate (ATP)-sensitive K+ channels has not been demonstrated in precapillary microvessel levels. Therefore, the current study was designed to examine whether ATP-sensitive K+ channels play a role in vasodilation induced by mild hypercapnia in precapillary arterioles of the rat cerebral cortex. METHODS: Brain slices from rat cerebral cortex were prepared and superfused with artificial cerebrospinal fluid, including normal (Pco2 = 40 mmHg; pH = 7.4), hypercapnic (Pco2 = 50 mmHg; pH = 7.3), and hypercapnic normal pH (Pco2 = 50 mmHg; pH = 7.4) solutions. The ID of a cerebral parenchymal arteriole (5-9.5 microm) was monitored using computerized videomicroscopy. RESULTS: During contraction to prostaglandin F2alpha (5 x 10(-7) m), hypercapnia, but not hypercapnia under normal pH, induced marked vasodilation, which was completely abolished by the selective ATP-sensitive K+ channel antagonist glibenclamide (5 x 10(-6) m). However, the selective Ca2+-dependent K+ channel antagonist iberiotoxin (10(-7) m) as well as the nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester (10(-4) m) did not alter vasodilation. A selective ATP-sensitive K+ channel opener, levcromakalim (3 x 10(-8) to 3 x 10(-7) m), induced vasodilation, whereas this vasodilation was abolished by glibenclamide. CONCLUSION: These results suggest that in parenchymal microvessels of the rat cerebral cortex, decreased pH corresponding with hypercapnia, but not hypercapnia itself, contributes to cerebral vasodilation produced by carbon dioxide and that ATP-sensitive K+ channels play a major role in vasodilator responses produced by mild hypercapnia.  相似文献   
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