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991.
Angiography was used to diagnose a rare congenital coronary anomaly with myocardial ischaemia in a woman with typical angina. All three coronary arteries arose from a solitary coronary ostium in the right aortic sinus; the left anterior descending coronary artery followed a septal course, the circumflex coronary artery ran behind the ascending aorta, and the right coronary artery followed a normal course. No significant coronary lumen narrowing was found. Transoesophageal echocardiography confirmed the anomalous origin and course of the aberrant coronary arteries. An exercise test reproduced angina, and ECG changes and myocardial perfusion study showed an anterior reversible defect. In contrast to previous reports, myocardial ischaemia was associated with the septal (intramuscular) course of the left anterior descending coronary artery; there was no other significant coronary artery disease.


Keywords: congenital heart defects; myocardial ischaemia; angiography; echocardiography  相似文献   
992.
In patients with achalasia, it has beensuggested that pneumatic dilatation could makecardiomyotomy more difficult to perform, diminishing itsefficacy and safety. Our aim was to evaluate theefficacy and safety of elective cardiomyotomy afterfailure of pneumatic dilatation in achalasia. During 14years, 32 of 276 consecutive patients with achalasiahave been operated on because of failure of dilatation therapy. Twenty patients have been followed-upfor at least one year after surgery. After failure ofdilatation, Heller's cardiomyotomy and 180 anteriorfundoplication were performed. Clinical status was evaluated before and after surgery. Loweresophageal sphincter pressure and esophageal body basalpressure were measured by manometry, esophageal diameterby barium meal, and gastroesophageal reflux by endoscopy and 24-hr esophageal pH monitoring.No technical difficulties were found during operation.Postoperative morbidity was infrequent and mortality wasabsent. Cardiomyotomy improved clinical status in 19 of 20 patients. The results of surgerywere considered excellent or good in 16 patients (80%;CI: 56-94%). The pressure of the lower esophagealsphincter was significantly reduced, falling in most patients to under 10 mm Hg. Gastroesophagealreflux appeared after surgery in eight patients, four ofthem with endoscopic esophagitis, but it was controlledin all patients with medical therapy. In conclusion, cardiomyotomy is a safe and effective therapyin achalasia after failed pneumaticdilatation.  相似文献   
993.

Objective

A prospective study was carried out to assess HIV‐1 and HIV‐2 mother‐to‐child transmission (MTCT) rates in Portugal between 1999 and 2005 by analysing the proportion of diagnosed infected children born to HIV‐positive mothers.

Materials and methods

Serial blood samples were collected from 1315 children at risk of HIV‐1 infection, 131 children at risk of HIV‐2 infection and six children at risk of both HIV‐1 and HIV‐2 infections attending 25 Health Institutions. HIV proviral DNA was detected by nested polymerase chain reaction (PCR) and statistical analysis was performed using spss .

Results

DNA PCR using HIV‐1 and HIV‐2 long terminal repeat (LTR) primers amplified 92.5% and 75% of maternal HIV infections, respectively. Overall, MTCT occurred in 3.4% [95% confidence interval (CI) 2.5–4.6%] of HIV‐1 and 1.5% (95% CI 0.2–5.4%) of HIV‐2 mother–child pairs. A significant decrease in HIV‐1 MTCT was observed with time, from 7.0% (95% CI 2.6–14.6%) in 1999 to 0.5% (95% CI 0.0–2.5%) in 2005. HIV MTCT was associated with an absence of antiretroviral therapy in infected pregnant women (P<0.0001). Of the 48 infected children (46 with HIV‐1 and two with HIV‐2), the schedule of blood sample collection was followed for only 26 children. In 14 (53.8%) of those 26 children the infections were diagnosed in the first sample collected before they were 48 h old, suggesting in utero transmission. Despite the national recommendations for antenatal HIV testing, a high overall proportion (22.2% for HIV‐1 and 44.3% for HIV‐2) of mothers did not access any MTCT prevention measures, mostly because of late diagnosis in pregnancy. A small but significant proportion of HIV‐2 infection was found in mothers with no identifiable link with West Africa.

Conclusion

HIV‐2 transmission rates are low (1.5% in this study), and this may have led to a lower uptake of interventions, but in the absence of interventions transmission does occur. HIV‐1 transmission was also associated with a lack of intervention, mostly as a result of late presentation. Use of primers restricted to a single sequence led to false‐negative maternal results in a significant proportion of cases. In part this may have been attributable to very low HIV DNA loads as well as primer template mismatches. HIV infection was not documented in children born to mothers with negative HIV DNA PCR results.  相似文献   
994.
Background  Expanded adipose-derived stem cells (ASC) have been shown to be effective in treating Crohn’s patients with enterocutaneous fistulas. It is possible that unexpanded cells corresponding to the stromal vascular fraction (SVF) may also be effective. Materials and methods  A subpopulation of patients from a previous proof-of-concept phase I study with enterocutaneous fistulas received autologous expanded ASCs. The same selection criteria for inclusion were applied to patients who underwent SVF implantation to treat enterocutaneous fistulas. After tract curettage, cell suspensions (either SVF cells from lipoaspirate or expanded ASCs) were injected into the tract walls, and the fistulous tract was sealed with fibrin adhesive (with or without cells). Results  In the series that received ASCs, four fistulas could be evaluated, and cure was achieved in three out of four cases. In the series that received SVF cells, four fistulas were evaluated, with cure achieved in one out of four cases. Conclusions  Although a comparison of case series cannot be considered firm evidence, a therapeutic protocol that uses expansion prior to implantation does seem to be more effective than one that uses SVF cells directly from a lipoaspirate sample.  相似文献   
995.
The spatial distribution of neutral genetic diversity is mainly influenced by barriers to dispersal. The nature of such barriers varies according to the dispersal means and capabilities of the organisms concerned. Although these barriers are often obvious on land, in the ocean they can be more difficult to identify. Determining the relative influence of physical and biotic factors on genetic connectivity remains a major challenge for marine ecologists. Here, we compare gene flow patterns of 7 littoral fish species from 6 families with a range of early-life-history traits sampled at the same geographic locations across common environmental discontinuities in the form of oceanic fronts in the Western Mediterranean. We show that these fronts represent major barriers to gene flow and have a strong influence on the population genetic structure of some fish species. We also found no significant relation between the early-life-history traits most commonly investigated (egg type, pelagic larval duration, and inshore-offshore spawning) and gene flow patterns, suggesting that other life-history factors should deserve attention. The fronts analyzed and the underlying physical mechanisms are not site-specific but common among the oceans, suggesting the generality of our findings.  相似文献   
996.
The most relevant activities of clinical microbiologist and the laboratory in the surveillance and the control of nosocomial infections (NI) are mainly focused on the collection, analysis and management of the information obtained in the Microbiology Laboratory; the design, development and validation of microbiological techniques, particularly rapid tests for the early detection of nosocomial pathogens, especially those multi-drug resistant ones, and the study of the genetic relationship between them. It also assists in the design of specific programs for the prevention of the NI, and the evaluation of their impact, as well as taking part in educational and training programs on topics related to NI. The management of laboratory resources, and communications with hospital information systems is also important.  相似文献   
997.
The present study investigated the time-course for aging-associated effects on contractile and relaxing vascular responses and nitric oxide (NO) production in the aorta from female senescence-accelerated resistant (SAMR1) and prone (SAMP8) mice. Both SAMR1 and SAMP8 were studied at three different ages: 3 (young), 6 (middle age) and 10 (old) months. Concentration–response curves to phenylephrine (10− 8 to 10− 5 M) or acetylcholine (10− 9 to 10− 5 M) were performed in the aortic rings in the absence or in the presence of NO synthase (NOS) inhibitor L-NAME (10− 4 M). Protein and gene expression for endothelial NOS (eNOS) was determined by immunofluorescence, Western blot and real-time PCR. Although we have not seen any difference in vascular responses when comparing both strains at 3 months old, we found a significant aging-associated impairment of vascular reactivity that follows a distinct time-course in SAMR1 and SAMP8. In SAMR1, increases in phenylephrine contraction and decreases in acetylcholine relaxation were only seen at 10 months old, while SAMP8 displays altered responses at 6 months that are further impaired at 10 months old. L-NAME treatment enhanced phenylephrine contractions and completely inhibited acetylcholine relaxations in all age groups of SAMR1 and SAMP8. However, the magnitude of increase in phenylephrine contraction by L-NAME was markedly reduced by aging and followed a faster pace in SAMP8. Similar pattern of responses was observed in the time course for changes of eNOS expression, suggesting an earlier and more pronounced aging-associated decrease of NO production and eNOS expression in SAMP8. These results reveal that aging enhances contractile responses to phenylephrine and decreases endothelium-dependent relaxation to acetylcholine in the aorta from female mice by a mechanism that involves a decrease of NO production. This process occurs earlier in the aorta from SAMP8 mice, establishing these mice as suitable model to study cardiovascular aging in a convenient and standard time course.  相似文献   
998.
A study is presented on the presence of quinolone resistance qnrB1 genes in clinical isolates belonging to the largest series of infections caused by OXA-48-producing Klebsiella pneumoniae in a single-centre outbreak in Spain. Evidence is also provided, according to in vitro results, that there is a possibility of co-transfer of plasmid harbouring blaOXA-48 with an other plasmid harbouring qnrB1 in presence of low antibiotic concentrations of fluoroquinolones, showing the risk of multi-resistance screening.  相似文献   
999.
1000.
Summary Girls with a history of premature pubarche, i. e. appearance of pubic hair before 8 years of age, show hyperinsulinism in response to an oral glucose tolerance test. As hyperinsulinaemia has a major role in dyslipaemia, and is considered an independent risk factor for cardiovascular disease, we assessed the patterns of plasma insulin concentration after a standard oral glucose tolerance test as well as fasting serum lipid, lipoprotein, and sex hormone-binding globulin concentrations in girls (n = 81) with premature pubarche compared with girls (n = 55) matched with them for stage and bone age to ascertain their metabolic states to identify those potentially at risk for the development of premature cardiovascular disease. Mean serum insulin concentrations were higher in patients at all pubertal stages, and associated with elevated serum triglyceride, very low density cholesterol and very low density triglyceride concentrations (p value range 0.04 to < 0.0001) but reduced sex hormone-binding globulin. Premature pubarche patients also displayed higher low density to high density lipoprotein cholesterol ratios compared with control subjects (p = 0.004 to 0.008). In conclusion, hyperinsulinaemia, decreased sex hormone-binding globulin concentrations and an unfavourable lipid pattern are common features in premature pubarche girls supporting the contention that atherogenic abnormalities composing the metabolic syndrome could start in childhood. To determine the clinical sequelae of such clustering of metabolic deviations, girls who were identified need to be followed up for the potential development of premature cardiovascular disease. [Diabetologia (1998) 41: 1057–1063] Received: 27 January 1998 and in final revised form: 11 May 1998  相似文献   
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