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31.
Embolic stroke is a common complication in patients on ventricular assist devices in both adults and children. The reported incidence of strokes in children supported by VAD's varies from 7 to 38%. The rapid increase in recent years in the availability of both adult and pediatric VADs will likely add to the overall prevalence of strokes in patients being bridged to heart transplant. Strokes in this population can be lethal as they frequently necessitate withdrawal of the extracorporeal device support and withdrawal from the organ transplant waiting list. We present a case of a fully anti-coagulated 29-month-old supported on a Berlin EXCOR LVAD (Berlin, Germany) with embolic stroke which was treated successfully with direct thrombolysis with recombinant tissue plasminogen activator. This is the first report which uses intra-arterial thrombolytics while on a ventricular assist device in a pediatric patient.  相似文献   
32.
OBJECT: Medically refractory symptomatic vertebrobasilar atherosclerotic disease has a poor prognosis. Studies have shown that longer (> or = 10 mm), eccentric, high-grade (> 70%) stenoses portend increased procedure-related morbidity. The authors reviewed their experience to determine whether a staged procedure consisting of angioplasty followed by delayed (> or = 1 month later) repeated angioplasty and stent placement reduces the morbidity associated with endovascular treatment of symptomatic basilar and/or intracranial vertebral artery (VA) stenoses. METHODS: The authors retrospectively reviewed the medical records in a consecutive series of eight patients who underwent planned stent-assisted angioplasty for medically refractory, symptomatic atherosclerotic disease of the intracranial posterior circulation between February 1999 and January 2002. Staged stent-assisted angioplasty was planned for these patients because the extent and degree of stenosis of the VA and/or basilar artery (BA) lesion portended an excessive procedure-related risk. The degree of stenosis, recent onset of symptoms (unstable plaque), vessel tortuosity, and lesion length and morphological feaures were contributing factors in determining procedure-related risk. Patient records were analyzed for location and degree of stenosis, preprocedural regimen of antiplatelet and/or anticoagulation agents, devices used, procedure-related complications, and clinical and radiographic outcomes. Among the patients in whom staged stent-assisted angioplasty was planned, vessel dissection, which necessitated immediate stent placement, occurred during passage of the balloon in one of them. In a second patient, the stent could not be maneuvered through the tortuous VA. In a third patient, the VA and BAs remained widely patent after angioplasty alone, and therefore stent placement was not required. Significant complications among the eight patients included transient aphasia and hemiparesis in one and a groin hematoma that necessitated surgical intervention in another; there was no permanent neurological morbidity. The mean stenosis before treatment was 78%, which fell to 54% after angioplasty, and the mean residual stenosis after stent placement was 30%. At the last follow-up examination, none of the treated patients had further symptoms attributable to the treated stenosis. CONCLUSIONS: The novel combination of initial angioplasty followed by delayed endoluminal stent placement may reduce the neurological morbidity associated with endovascular treatment of long, high-grade stenotic lesions. Attempting to cross high-grade stenoses with higher-profile devices such as stents may result in an embolic shower. Furthermore, neointimal proliferation and scar formation after angioplasty result in a thickened fibrous layer, which may be protective during delayed stent deployment. Larger-scale studies involving multiple centers are needed to elucidate further the lesion morphological characteristics and patient population most likely to benefit from staged procedures.  相似文献   
33.

Purpose

This study aimed to determine the effect of melatonin in preventing ischemia-reperfusion (I-R) injury-induced tissue damage and on spermatogenesis after experimental testicular torsion (TT).

Methods

Forty peripubertal rats were divided into 4 groups each containing 10 rats: control (C), sham (S), torsion plus detorsion (TD), and torsion plus melatonin (M). The left testes were rotated 720° for 6 hours and detorsed for 6 hours thereafter. Serum inhibin B (IB) levels were measured in blood samples taken from all groups. Left orchiectomies were performed to determine the tissue levels of Johnsen's scores (JS) and malondialdehyde (MDA).

Results

Serum IB levels in the S and TD groups were significantly lower compared with that in the C group, whereas they were higher in the M group compared with the TD group. The MDA levels were significantly lower in the C, S, and, M groups compared with the TD group. Johnsen's scores were significantly higher in the C, S, and M groups compared with the TD group.

Conclusions

Our results suggested that melatonin is a potent antioxidant agent in preventing testicular I-R injury, as shown by increased IB levels and JS.  相似文献   
34.
Nephrotoxicity is a major complication of acetaminophen (APAP), a widely used analgesic and antipyretic drug, and there is no specific treatment for APAP-induced renal damage. It has been reported that reactive oxygen metabolites or free radicals are important mediators of APAP toxicity. In this study, the protective role of melatonin (MLT) on APAP-induced nephrotoxicity was investigated in rats. For this purpose, nephrotoxicity was induced in male Wistar albino rats by intraperitoneal (i.p.) administration of a single dose of 1,000 mg/kg APAP. Some of these rats also received i.p. melatonin (10 mg/kg) 20 min after administration of APAP. The rats were sacrificed 24 h after administration of APAP. Urea and creatinine levels were measured in the blood, and levels of malondialdehyde (MDA) and glutathione (GSH), and glutathione peroxidase (GSH-Px), catalase (CAT), and superoxide dismutase (SOD) activity were determined in renal tissue. Serum urea and creatinine levels increased significantly as a result of APAP nephrotoxicity. A significant increase in MDA and decreases in GSH level and GSH-Px, CAT, and SOD activity indicated that APAP-induced renal damage was mediated through oxidative stress. Significant beneficial changes were noted in serum and tissue oxidative stress indicators in rats treated with MLT. These biochemical observations were supplemented by histopathological examination of kidney sections, which revealed that MLT also reduced the severity of APAP-induced histological alterations in the kidney. These results indicate that administration of APAP causes oxidative stress to renal tissue and that MLT protects against the oxidative damage associated with APAP.  相似文献   
35.
OBJECT: Endovascular treatment of acute thromboembolic stroke is a rapidly developing field that appears to hold great promise. Young patients may be particularly suited to benefit from endovascular acute stroke therapy. The authors sought to identify outcomes in young patients with thromboembolic stroke who underwent endovascular intervention. METHODS: The authors retrospectively reviewed a prospectively collected endovascular intervention registry of patients with ischemic strokes treated at a single large-volume institution between December 2000 and June 2007 to identify patients 18-35 years of age who were treated for thromboembolic stroke. Data are presented as the mean +/- standard deviation unless otherwise noted. RESULTS: Seven young patients underwent 8 consecutive endovascular interventions for thromboembolic stroke (mean age 26 +/- 6 years; 5 women). The National Institutes of Health Stroke Scale score at presentation was 13 +/- 4.3 (median 13). All patients presented within 6 hours of symptom onset. Revascularization was attempted with mechanical thrombectomy/disruption, intraarterial thrombolysis, and/or angioplasty, with or without stent placement. The modified Rankin Scale (mRS) score at discharge was 2.2 +/- 1.5 (median 1.5), with 5 patients (62.5%) achieving independence at discharge (mRS Score 0-2). There were no deaths. Hospital length of stay was 6.5 +/- 3.7 days (4.4 +/- 1.5 days for patients with an mRS score of 0-2; 10 +/- 3.6 days for patients with an mRS score of 4). All patients became independent and had reached an mRS score of < or = 2 at last follow-up evaluation (29 +/- 25 months). CONCLUSIONS: The data demonstrate the relative safety of endovascular intervention in young patients with thromboembolic cerebral ischemia and may suggest a potential benefit in outcome. Further investigation is indicated with larger numbers of patients and an appropriate control population.  相似文献   
36.
The non-stationary and multi-frequency nature of biomedical signal activities makes the use of time-frequency distributions (TFDs) for analysis inevitable. Time-frequency analysis provides simultaneous interpretations in both time and frequency domain enabling comprehensive explanation, presentation and interpretation of electrocardiogram (ECG) signals. The diversity of TFDs and specific properties for each type show the need to determine the best TFD for ECG analysis. In this study, a performance evaluation of five TFDs in term of ECG abnormality detection is presented. The detection criteria based on extracted features from most important ECG signal components (QRS) to detect normal and abnormal cases. This is achieved by estimating its energy concentration magnitude using the TFDs. The TFDs analyse ECG signals in one-minute interval instead of conventional time domain approach that analyses based on beat or frame containing several beats. The MIT-BIH normal sinus rhythm ECG database total records of 18 long-term ECG sampled at 128 Hz have been analysed. The tested TFDs include Dual-Tree Wavelet Transform, Spectrogram, Pseudo Wigner-Ville, Choi-Williams, and Born-Jordan. Each record is divided into one-minute slots, which is not considered previously, and analysed. The sample periods (slots) are randomly selected ten minutes interval for each record. This result with 99.44% detection accuracy for 15,735 ECG beats shows that Choi-Williams distribution is most reliable to be used for heart problem detection especially in automated systems that provide continuous monitoring for long time duration.  相似文献   
37.
OBJECTIVE: To evaluate corrected thrombolysis in myocardial infarction (TIMI) frame count (CTFC) in patients with angiographically normal coronary arteries and diabetes mellitus, a condition known to be associated with microvascular dysfunction. METHODS: Patients who underwent coronary angiography in Gazi University Hospital, Ankara, Turkey between January 2000 and January 2005 were studied. Corrected TIMI frame count was calculated over the left anterior descending (LAD), left circumflex (Cx) and right coronary arteries (RCA) in 118 diabetic and 122 non-diabetic patients with normal coronary angiogram. RESULTS: The mean CTFC values of the LAD, Cx, and the RCA were similar in diabetics and nondiabetics 21.0 +/= 7.5 versus 21.3 +/= 9.6, 23.3 +/= 9.7 versus 23.5 +/= 10.8, 17.9 +/= 6.7 versus 18.7 +/=7.4 respectively, p>0.05 for all comparisons. In stepwise multivariate linear regression analysis, body surface area had a significant correlation with CTFC of all the 3 coronary arteries. CONCLUSION: We conclude that CTFC in diabetics and non-diabetics with angiographically normal coronary arteries is similar. Since microvascular disease is an inherent component of diabetes, our finding may reflect the inadequacy of CTFC in predicting microvascular disease in diabetic patients with normal coronary angiograms.  相似文献   
38.
We aimed to assess the incidence of multiple primary malignancies in primary lung cancer patients. We retrospectively evaluated the clinical files of 1038 primary lung cancer patients diagnosed in 2004. Forty patients (3.9 %) had multiple primary malignancies. There were 34 men (85 %) and 6 women (15 %). Their mean age was 62.4 +/- 8.6 years. While 35 cases were smokers, 5 cases were nonsmokers. Tumour pathology of the lung was squamous cell carcinoma in 15 cases, adenocarcinoma in 10 cases, small cell carcinoma in 3 cases and non-small cell carcinoma in 12 cases. There were 2 primary tumours in 37 cases and 3 primary tumours in 3 cases. The first detected tumour was located in larynx in 11 cases, in genitourinary system in 9 cases, in intestine in 5 cases, in lung in 3 cases and in other organs in 12 cases. The mean interval between the first and the second tumour was 77 months with a range of 1 months to 32 years. This interval was shorter than 6 months in 4 cases. Treatment modality for the first detected tumour was surgery in 35 cases. The last primary tumour was treated with surgery in 12 cases. In conclusion, the development of multiple primary tumours is not a rare phenomenon. Patients with a malignancy should be followed for development of a second primary malignancy. The treatment of lung cancer in patients with a previous malignancy should be the same as for lung cancers presenting as the first cancer.  相似文献   
39.
OBJECTIVE: To determine whether Henle's spine could be used as a reliable and multipurpose landmark for the other important structures of the skull base. MATERIALS AND METHODS: Ninety-two specimens from 46 cadaveric adult dry skulls were studied. Two imaginary lines and a triangle were defined: a spinopterygoidal line extending from Henle's spine to the root of the medial pterygoid plate, a bispinal line extending from one Henle's spine to the contralateral one, and a parapetrosal triangle lying between the spinopterygoidal line, the bispinal line and the sagittal midline. The parapetrosal triangle encompasses nearly all the main structures of the skull base, including the petrosal internal carotid artery. RESULTS: Along the spinopterygoidal line the distance from Henle's spine to the spine of the sphenoid was found to be about 3 cm, to the foramen spinosum 3.5 cm, to the posterior and anterior margins of the foramen ovale 4 and 4.5 cm, to the root of the lateral pterygoid plate 5 cm, to the root of the medial pterygoid plate 5.5 cm, and to the vomer 6.5-7 cm. Along the bispinal line, the distance from Henle's spine to the stylomastoid foramen was found to be about 1.5 cm, to the lateral and medial margins of the jugular foramen 2.5 and 3.5 cm, to the external orifice of the hypoglossal canal 4 cm, and to the foramen magnum 5 cm. CONCLUSION: Henle's spine with its superficial and central position can be used to localize important anatomical structures during skull-base surgery.  相似文献   
40.
We evaluated neodymium-doped yttrium-aluminum-garnet (Nd:YAG) laser posterior capsulotomy procedure with or without anesthesia in 35 pediatric eyes and 51 adult eyes. We concluded that Nd:YAG laser posterior capsulotomies in children are similar to adults in general aspects and that Nd:YAG laser capsulotomy can be performed safely and effectively in children under topical or no anesthesia.  相似文献   
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