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111.
A 13-year-old male patient, who underwent Mustard operation for a very complex congenital heart disease (CHD), after palliation presented a decrease of the sinus node function, developing a tachy-brady syndrome and a mild dysfunction of atrioventricular (AV) conduction. He was successfully treated using a DDDRP pacemaker, which ensured a suitable atrial rhythm and was able to interrupt supraventricular tachycardia episodes. Until now, hospitalization related to episodes of heart failure or symptomatic arrhythmia, has not been necessary.  相似文献   
112.
1-Thioangelicin is a furocoumarin analog synthesized to investigate the role of the substitution of sulfur for oxygen in the parent compound angelicin. The compound was examined by X-ray diffraction, and its interaction with DNA, both in the dark and by UVA irradiation, studied by means of linear flow dichroism, chromatography and (1)H NMR. Further insight into the steric and electronic features of 1-thioangelicin has been reached through theoretical calculations, including molecular mechanics optimization, docking studies and frontier molecular orbital investigations. The experimental data indicate that thioangelicin is able to intercalate in the DNA helix and subsequent irradiation yields a cis-syn adduct, in agreement with theoretical calculations within the lower/higher singly occupied molecular orbital formalism. Antiproliferative activity has been assessed on Balb/c 3T3 cultured cells.  相似文献   
113.
Since 2001, 50 breast cancer patients, for whom extensive lung/heart involvement was expected from the use of conventional tangential 2-field technique (2F) owing to complex anatomies, were irradiated using a 3-field conformal technique (3F). Dose plans were designed for both 3F and 2F and a dose volume histogram analysis on ipsilateral lung, heart, and target was conducted. The 3F technique allowed a significant reduction in ipsilateral lung irradiation: mean dose dropped from 16.0±3.8 (2F) to 12.0±2.7 Gy (3F) and V45Gy from 20.7±6.8 (2F) to 3.2±2.9% (3F). Similarly, in patients irradiated to the left breast, heart mean dose was reduced from 8.1 Gy (2F) to 6.8 Gy (3F) and D15% from 19.0 Gy to 14.0 Gy. All differences reached a high degree of significance. The target coverage was not clinically compromised since the slight reduction using 3F compared with 2F is limited to V95% while V90% difference, even if statistically significant, is small: 98.2±1.8% (3F) and 98.8±1.6 (2F). A preliminary report on clinical follow up is also included; with a mean follow up of 15.8 months, no pulmonary or cardiac complications were observed.  相似文献   
114.
Coronary angiography is nowadays the diagnostic standard in the evaluation of coronary artery anatomy, in the identification of stenoses and in the follow-up of revascularization procedures (PTCA-stenting, bypass). The limitations of such technique in terms of invasivity and high cost has targeted research efforts towards the development of non invasive diagnostic tools. Technological evolution in the field of helical CT has provided 2, 4, 8 and 16 detector-row multislice scanners characterized by progressive improvements in terms of spatial and temporal resolution that have made them increasingly suitable for the analysis of moving structures with high quality anatomic detail. The main cardiologic applications of multislice CT include coronary calcium scoring, the evaluation of coronary vascular anatomy and disease, follow-up of revascularization procedures (stenting, bypass), and the evaluation of cardiac walls and chambers. The aim of this paper is to describe the applications of sixteen detector-row multisclice CT in non invasive evaluation of cardiac and coronary diseases.  相似文献   
115.
AIM: To assess whether axillary temperature measurements reliably reflect oral/rectal temperature measurements. METHODS: This observational study compared paired axillary-rectal and axillary-oral temperatures in a general paediatric ward with the participation of 225 children aged < or = 4 y and 112 children aged between 4 and 14 y. RESULTS: Changes in oral/rectal and axillary temperatures correlated significantly (p < 0.0001). However, axillary temperature measurements were significantly lower than both oral (mean -0.56 degrees C, SD 0.76 degrees C) and rectal measurements (0.38 degrees C; SD 0.76 degrees C). Ninety-five percent of axillary measurements fell within a 2.5-3 degrees C range around respective paired oral/rectal measurements. The mean difference increased with increasing temperature, and was 0.4 degrees C at low body temperatures, and over 1 degree C with a fever of 39 degrees C. Neither seasonal fluctuations nor the amount of clothing worn influenced this difference. CONCLUSION: Axillary temperatures in young children do not reliably reflect oral/rectal temperatures and should therefore be interpreted with caution.  相似文献   
116.
Arrhythmogenic right ventricular cardiomyopathy type 1 (ARVD1) is an autosomal dominant disorder characterised by progressive degeneration of right ventricular myocardium, arrhythmias and risk of sudden death. By linkage analysis, we previously mapped the involved gene to chromosome 14q24.3. In the present study we report on linkage analysis of one additional and unrelated family, which enabled to confirm previous locus assignment. Another family is reported, in which genetic and clinical data suggest linkage to the same locus. Direct sequencing of DNA from individuals belonging to established ARVD1 families failed to detect causative mutations in exonic sequences of four genes (POMT2, TGFbeta3, KIAAA1036 and KIAA0759) expressed in the heart and which defects could possibly induce plasma membrane instability or apoptosis, key features of ARVD pathogenesis.  相似文献   
117.
Due to the clearly demonstrated receptor-receptor interaction between adenosine A(2A) and dopamine D(2) receptors in the basal ganglia, the discovery and development of potent and selective A(2A)adenosine receptor antagonists became, in the last ten years, an attractive field of research to discovery new drugs for the treatment of neurodegenerative disorders, such as Parkinsons disease. Different compounds have been deeply investigated as A(2A) adenosine receptor antagonists, which could be classified in two great families: xanthine derivatives and nitrogen poliheterocyclic systems. These studies led to the discovery of some highly potent and selective A(2A) adenosine receptor antagonists such as ZM241385, SCH58261 and some xanthine derivatives (KW6002), which have been used as pharmacological tools for studying this receptor subtype. However, those compounds showed some problems that do not permit their use in clinical studies, such as poor water solubility (SCH58261, and xanthine derivatives) or good affinity for A(2B) adenosine receptor subtype (ZM241385). In the last few years great efforts have been made to overcome these problems, trying to optimize not only the pharmacological profile but also the pharmacokinetic character of this class of compounds. The aim of this report is to briefly summarize the recent progress made in this attractive field of research.  相似文献   
118.
A new series of pyrazolo[4,3-e]-1,2,4-triazolo[1,5-c]pyrimidines bearing various substituents at both the N5-pyrimidinyl and N8-pyrazolyl positions have been synthesized, and their binding affinities at the four human adenosine receptor subtypes (hA(1), hA(2A), hA(2B), and hA(3)) have been evaluated. All the described compounds contain arylacetyl moieties at the N5 position and arylalkyl substituents at the N8 position. Surprisingly, all the compounds present their most potent affinities at the hA(2B) adenosine receptor with a range of selectivities against the other subtypes. When bulky groups are present simultaneously at the N5 and N8 positions (e.g., compound 9), the best selectivity for the hA(2B) receptor was observed (K(i)(hA(1)) = 1100 nM; K(i)(hA(2A)) = 800 nM; K(i)(hA(2B)) = 20 nM; K(i)(hA(3)) = 300 nM, K(i)(hA(1)/A(2B)) = 55, K(i)(hA(2A)/A(2B)) = 40, K(i)(hA(3)/hA(2B)) = 15). To understand the molecular significance of these results, we compared the putative TM (transmembrane) binding motif of compound 9 on both hA(2B) and hA(3) receptors. From our docking studies, compound 9 fits neatly inside the TM region of the hA(2B) receptor but not in the corresponding hA(3) region, illustrating significant differences between the two subtypes. The study herein presented permits an understanding of why the bioisosteric replacement of an -NH, present in previously reported hA(3) receptor antagonists, with a -CH(2) group at the N5 position induces such large differences in hA(2B)/hA(3) affinity. In the molecular structure of the hA(3) receptor, two residues, Ser243 (TM6) and Ser271 (TM7), create a hydrophilic region, which seems to permit a better accommodation of the phenylurea series into this putative hA(3) binding site than the phenylacetyl series.  相似文献   
119.
AIMS—To compare two strategies for the eradication of Helicobacter pylori infection.METHODS—Groups 1 and 2 each consisted of 75 consecutive patients. Patients in group 1 were treated with two antibiotics based on antibiotic susceptibility testing; those in group 2 received amoxycillin and clarithromycin for eight days, together with either ranitidine or omeprazole. Eradication rate was assessed in both groups six months after treatment.RESULTS—In group 1, H pylori grew in culture in 63/75 cases. Susceptibility testing showed that 35/63 isolates were resistant to metronidazole, 10/63 to clarithromycin, 2/63 to ampicillin, 1/63 to tetracycline, and 5/63 to both clarithromycin and metronidazole. In group 1the infection was eradicated in 96% of the initial 75 subjects, and in 98% of the subjects treated according to the antibiotic assay (62/63). As two patients were lost at follow up the overall eradication rate was 99%. In group 2, eradication was achieved in 61/75 subjects (81%). This was significantly lower than the percentage of eradication observed in group 1 (81% versus 99%).CONCLUSIONS—Antibiotic susceptibility tests are useful in childhood as a very high percentage of subjects are cured. This approach is costly, but selective antibiotic treatment contributes to limit further development of antibiotic resistance, and money is saved in terms of reinvestigation and further repeated treatments.  相似文献   
120.
The peri-ventricular area of the forebrain constitutes a preferential site of inflammation in multiple sclerosis, and the sub-ventricular zone (SvZ) is functionally altered in its animal model experimental autoimmune encephalomyelitis (EAE). The reasons for this preferential localization are still poorly understood. We show here that, in EAE mice, blood-derived macrophages, T and B cells and microglia (Mg) from the surrounding parenchyma preferentially accumulate within the SvZ, deranging its cytoarchitecture. We found that the chemokine Cxcl10 is constitutively expressed by a subset of cells within the SvZ, constituting a primary chemo-attractant signal for activated T cells. During EAE, T cells and macrophages infiltrating the SvZ in turn secrete pro-inflammatory cytokines such as TNFα and IFNγ capable to induce Mg cells accumulation and SvZ derangement. Accordingly, lentiviral-mediated over-expression of IFNγ or TNFα in the healthy SvZ mimics Mg/microglia recruitment occurring during EAE, while Cxcl10 over-expression in the SvZ is able to increase the frequency of peri-ventricular inflammatory lesions only in EAE mice. Finally, we show, by RT-PCR and in situ hybridization, that Cxcl10 is expressed also in the healthy human SvZ, suggesting a possible molecular parallelism between multiple sclerosis and EAE.  相似文献   
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