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61.
BACKGROUND: Alpha-adrenergic agents contract vascular smooth muscle (VSM) and stimulate endothelial release of secondary factors which modulate VSM contraction. Our study examined constrictor prostanoid (cPN) and nitric oxide (NO) as secondary factors which could alter alpha-1 adrenoceptor-mediated contraction during sepsis. METHODS: Sepsis was induced in rats by inoculation of an implanted sponge with Escherichia coli and Bacteroides fragilis. Aortic rings at 24 h from septic (n = 21) and control (n = 21) rats were suspended in physiological salt solution (PSS) with or without blockers to NO (N(G)-monomethylarginine), cPN (mefenamic acid, MFA), or thromboxane A2 (SQ29548). Contraction dose-response curves were generated to determine maximal contraction force (F(max)) and pD2 (sensitivity) to phenylephrine in each experimental group. RESULTS: Sepsis increased F(max) to phenylephrine (PHE) (1.18 vs 0.90 g, SEM 0.0703). COX inhibition reduced the F(max) in control (0.63 vs 0.90 g, SEM 0.0675) but not in septic animals (1.19 vs 1.18 g, SEM 0.0433). TXA2 receptor inhibition did not alter F(max) in control (1.017 vs 0.973 g, SEM 0.0959) or septic animals (1.28 vs 1.12 g, SEM 0.0823). NOS inhibition enhanced the F(max) in both nonseptic (2.03 vs 0.83 g, SEM 0.0523) and septic rats (1.96 vs 1.15 g, SEM 0.0526), but did less so in the septic animals. CONCLUSIONS: PHE-induced F(max) is determined by a balance between PHE-stimulated VSM alpha-adrenoceptor activity, and PHE-stimulated endothelial release of cPN and NO. Sepsis enhances total PHE-induced F(max) by increasing VSM alpha-adrenoceptor activity and reducing PHE-stimulated endothelial release of dilator NO. Sepsis abolishes the PHE-stimulated endothelial release of cPN. PHE-stimulated cPN is not thromboxane A2, but could be a nonprostanoid dilator in the lipoxygenase (HETE) or cytochrome P450 (EET) pathways.  相似文献   
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The emissions from medical waste incinerators might perform a threat to the environment and the Public Health, the aim of the present work is to evaluate the emissions of six medical waste incinerators in six hospitals in Alexandria, Namely; Gamal Abd El-Naser, Sharq El-Madina, Central Blood Bank, Fever, Medical Research Institute, and Al-Mo'asat, ordered serially from 1 to 6. Five air pollutants were sampled and analyzed in the emissions comprising smoke, lead, carbon monoxide, sulphur dioxide and nitrogen oxides. The results of the present study have revealed that all the average values of gases in the six incinerators were within the limits stated in Egyptian environmental law, where as carbonaceous particulate (smoke) averages of the six incinerators have exceeded the maximum allowable limit in the law. On the other hand, lead concentration in emissions were far below the maximum allowable limit in the law. Al-Mo'asat incinerator emissions have been significantly higher in CO, NO2, SO2 and smoke concentration than the other five incinerators P < 0.001, P < 0.0006, P < 0.0001, and P < 0.002 respectively. The main recommendations of the present work are to reassess the limits of emissions in the Egyptian law and to state specific limits for medical wast incinerators and to relocate the medical waste incinerators away from residential areas or to substitute them all by a central incinerator in a proper place out of the city.  相似文献   
63.
BackgroundRecently, measurement of serum circular RNAs (circRNAs) as a non‐invasive tumor marker has been considered more. We designed the present study to investigate the diagnostic efficiency of serum Circ‐ELP3 and Circ‐FAF1, separately and simultaneously, for diagnosis of patients with breast cancer.MethodsSeventy‐eight female patients diagnosed as primary breast cancer participated in this study. We measured the level of circRNAs in serum specimens of the studied subjects. A receiver operating characteristic (ROC) curve was plotted and the diagnostic efficiency for both circRNAs was determined.ResultsCompared to non‐cancerous controls, Circ‐ELP3 was upregulated in breast cancer patients (p‐value = 0.004). On the other hand, serum Circ‐FAF1 was seen to be decreased in breast cancer patients than controls (pvalue = 0.001). According to ROC curve results, the area under the curve (AUC) for Circ‐ELP3 and Circ‐FAF1 was 0.733 and 0.787, respectively. Furthermore, the calculated sensitivity and specificity for Circ‐ELP3 and Circ‐FAF1 were 65, 64% and 77, 74%, respectively. Merging both circRNAs increased the diagnostic efficiency, with a better AUC, sensitivity and specificity values of 0.891, 96 and 62%, respectively.ConclusionBriefly, our results revealed the high diagnostic value for combined circRNAs panel, including Circ‐ELP3 and Circ‐FAF1 as a non‐invasive marker, in detection of breast carcinomas.  相似文献   
64.

Background  

Completion axillary lymph node dissection (CALND) is controversial in patients with sentinel lymph node (SLN) metastases ≤ 0.2 mm [N0 (i+)]. Our goal was to characterize patients with SLN isolated tumor cells regarding surgical management and axillary recurrence.  相似文献   
65.
Twenty-four adults with ALL were treated with AMSA alone or in combination. Twenty-two were treated at time of relapse and two patients after failing primary induction therapy. All had been treated with anthracyclines prior to receiving AMSA. Of the 22 patients with ALL in relapse, 4 achieved a complete remission. Two of these patients have relapsed while receiving maintenance chemotherapy; one died 1 mo after achieving remission due to the occurrence of cholycystitis in the setting of pancytopenia and one patient underwent bone marrow transplantation and is in remission at 8 mo after the second remission. Both patients who failed primary induction therapy remain in remission at 11 and 36 mo, respectively. The use of AMSA should be considered for patients with ALL who fail primary induction as well as those whose leukemia becomes resistant to conventional agents.  相似文献   
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67.

Purpose  

Neonatal neoplasms are rare tumours notorious for their atypical presentation and unpredictable behaviour. Their optimal treatment remains uncertain, a dilemma compounded by the deleterious effects of adjuvant chemo- or radiotherapy during this vulnerable period of growth. This paper examined the relatively high incidence of these tumours and its impact on paediatric surgery in Malaysia.  相似文献   
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