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41.
Heavily calcified ascending aorta significantly increased morbidity and lethality during open-heart surgery. Cannulation and clamping (partial or total) of severely atherosclerotic ascending aorta can easily cause damage and rupture of aortic wall, with consequential distal (often fatal) embolization with atheromatous debris (brain, myocardium). From June 1998. until June 2000, 11 of 2,136 (0.5%) patients who underwent coronary artery bypass grafting were with the severe atheromatous ascending aorta. The site of cannulation was in the aortic arch in three patients (aorta was occluded with Foley catheter in one case, and single clamp technique was used in the other two cases). The femoral artery was the cannulation site in other five cases. Profound hypothermia, ventricular fibrillation, and circulatory arrest, with no cross-clamping or cardioplegia, were used in three patients. Two patients were operated on with extracorporeal circulation, one in normothermia, on the beating heart, the other in moderate hypothermia, on fibrillating heart. In three patients myocardial revascularization was performed on the beating heart, in normothermia, without extracorporeal circulation. Postoperative course was uneventful in all 11 patients. Neither atheroembolism in the peripheral organs, nor atheroembolism of the extremities occurred. The proposed surgical approaches have the potential to reduce the prevalence of stroke and systemic embolization associated with coronary artery bypass grafting in patients with heavily calcified ascending aorta. This result was achieved due to the applied modifications of standard cardiosurgical technique.  相似文献   
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4,4'-dihydroxybenzophenone-2,4-dinitrophenylhydrazone (A-007) has recently completed a phase I clinical trial in advanced cancer with minimal toxicity, and impressive objective responses were noted. A-007 possesses three moieties that appear to have an influence on its anticancer activities: diphenylmethane, hydrazone, and dinitrophenyl. The goals of this study were to modify A-007's chemical moieties with the ultimate goal of maximizing its anticancer activity through increased planarity and introduction of functional groups. Thirty-five phenylhydrazone analogues of A-007 were synthesized and evaluated in vitro in a human primary cancer explant assay. Anticancer activities for selected analogues were also assayed for activity vs established human/murine cell lines. One-hundred-eighty-six fresh human solid tumors were used to screen for anticancer activity. Selected analogues were assayed for therapeutic indices (vs GM-CFC from bone marrow) in preparation for preclinical studies. Several polyaryl phenylhydrazones demonstrated improved cytotoxic activities by factors of 10(2)-10(3) when compared with A-007. However, the polyaryl quinone moieties of the latter analogues introduced potential toxic properties (cardiac, hematological) that do not exist with A-007.  相似文献   
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This study was designed to define the individual variables influencing subjective noise sensitivity in an urban population and to investigate the distribution of subjective noise sensitivity with regard to noise exposure. A general questionnaire, a ten-graded noise annoyance scale, the Weinstein's Noise Sensitivity Scale, and the Eysenck Personality Questionnaire were applied to a sample of 413 inhabitants of Belgrade. Distribution of noise sensitivity scores was normal and independent of noise exposure. No significant differences in average noise sensitivity scores were observed concerning gender and exposure to low (Leq < 55 dBA), and high level of traffic noise (Leq > 65 dBA). Multiple regression analysis revealed that neuroticism was the best individual predictor for SNS, for both sexes in the noisy area and for women only, in the quiet area (P < 0.001). Age, education level and introversion were not significantly related to noise sensitivity. Positive relation between reported noise annoyance and noise sensitivity was highly significant (P < 0.0001).  相似文献   
47.

Inherited antithrombin (AT) deficiency is a rare autosomal dominant disorder, caused by mutations in the AT gene (SERPINC1). Considering that the genotype phenotype relationship in AT deficiency patients remains unclear, especially in pediatric patients, the aim of our study was to evaluate genotype phenotype correlation in a Serbian pediatric population. A retrospective cohort study included 19 children younger than 18 years, from 15 Serbian families, with newly diagnosed AT deficiency. In 21% of the recruited families, mutations affecting exon 4, 5, and 6 of the SERPINC1 gene that causes type I AT deficiency were detected. In the remaining families, the mutation in exon 2 causing type II HBS (AT Budapest 3) was found. Thrombosis events were observed in 1 (33%) of those with type I, 11 (85%) of those with AT Budapest 3 in the homozygous respectively, and 1(33%) in the heterozygous form. Recurrent thrombosis was observed only in AT Budapest 3 in the homozygous form, in 27% during initial treatment of the first thrombotic event. Abdominal venous thrombosis and arterial ischemic stroke, observed in almost half of the children from the group with AT Budapest 3 in the homozygous form, were unprovoked in all cases.

Conclusion: Type II HBS (AT Budapest 3) in the homozygous form is a strong risk factor for arterial and venous thrombosis in pediatric patients.

What is Known:

Inherited AT deficiency is a rare autosomal dominant disorder, caused by mutations in the SERPINC1gene.

The genotype phenotype correlation in AT deficiency patients remains unclear, especially in pediatric patients.

What is New:

The genetic results for our paediatric population predominantly showed the presence of a single specific mutation in exon 2, that causes type II HBS deficiency (AT Budapest 3).

In this group thrombosis mostly occurred as unprovoked, in almost half of them as abdominal thrombosis or stroke with high incidence of recurrent thrombosis, in 27% during initial treatment.

  相似文献   
48.
来自五项随机或半随机对照研究的证据表明,桡骨远端骨折常优先采用经皮穿针合并石膏固定治疗而非单纯的石膏固定,但是在大多数的临床试验中发现,两种治疗方法的效果并无统计学差异.在解剖测量和功能评分方面,经皮穿针固定(除Kapandlii穿针外)与石膏固定的效果相近或较之更好,并且并发症的发生率更低.采用Kapandii穿针技术时,在功能评分方面与石膏固定效果相当,但是桡侧缩短畸形更为严重,而且桡神经浅支的损伤也更为常见.这些结果并不代表最终的结论,根据标准指引进一步开展严格的临床试验将会更有利.  相似文献   
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BACKGROUND: The aim of this study was to examine prothrombogenic factors and antioxidative defense in obese children and adolescents with pre-metabolic and metabolic syndrome, and to analyze insulin secretion and resistance, early glycoregulation disorders and lipid status. METHODS: Insulin sensitivity was determined using the homeostasis model assessment for insulin resistance (HOMA-IR), while insulin secretion was determined using the homeostasis model assessment beta (HOMA-beta). Prothrombogenic factors analyzed were plasma plasminogen activator inhibitor-1 (PAI-1) and fibrinogen. Superoxide dismutase and glutathione peroxidase were measured as markers of antioxidative defense. RESULTS: Patients with metabolic syndrome were characterized with increased body mass index (BMI), waist circumference, and HOMA-IR and HOMA-beta levels, and all had increased blood pressure and triglyceride levels, low high-density lipoprotein cholesterol levels, increased PAI-1 levels and reduced antioxidative defense levels. Patients with pre-metabolic syndrome had higher levels of basal and mean insulinemia during an oral glucose tolerance test, higher levels of HOMA-beta and lower levels of antioxidative defense compared to patients with metabolic syndrome. CONCLUSIONS: Negative correlations between antioxidative defense parameters and BMI, abdominal obesity, insulin secretion, systolic blood pressure and atherogenic lipid factors, as well as correlations between PAI-1 and insulin resistance and basal glycemia in the metabolic syndrome group contribute to accelerated atherosclerosis. Positive correlations between PAI-1 and waist circumference and BMI, and negative correlations between BMI and antioxidative defense in the pre-metabolic syndrome patients show that this early stage preceding the metabolic syndrome is also characterized by atherosclerotic complication risks and evident hyperinsulinism and insulin resistance.  相似文献   
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