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101.
Bland-White-Garland syndrome (BWG) is a rare congenital anomaly that is predominantly discovered in infancy. BWG is characterized by an anomalous origin of the left coronary trunk from the pulmonary artery that produces a coronary steal phenomenon, left-to-right shunt, and thus an abnormal left ventricular perfusion. The latter may induce myocardial necrosis, left ventricular dysfunction and commonly associated with mitral regurgitation. Despite its high mortality without surgical repair in infancy, several cases were reported to reach adulthood. In some patients, however, BWG was revealed only in older age, and may cause mild symptoms. Recent developments in cardiovascular MRI enable the determination of heart function, viability and perfusion with high resolution. We present three middle-aged female BWG cases indicating that MRI studies may give further insight into the therapeutic decision making in this age-group.  相似文献   
102.
Left ventricular pseudo-pseudoaneurysm is an extremely rare complication of myocardial infarction. In this condition the postinfarction rupture of the myocardium is not transmural, but remains circumscribed within the ventricular muscle itself as a cavity joining to the left ventricle through a narrow neck. The differentiation between postinfarction pseudoaneurysms and pseudo-pseudoaneurysms may be very difficult using conventional imaging techniques, such as transthoracic, or transesophageal echocardiography and left ventricular angiography. Cardiac MRI (CMR), however, is capable of distinguishing among anatomical structures such as pericardium, thrombus, and myocardium. In our report a chronic postinfarction pseudo-pseudoaneurysm is described by CMR in a patient with an old myocardial infarction.  相似文献   
103.
There is a two-way traffic of immune cells through the placenta; and fetal immune cells are often present in the maternal body even long after giving birth. We present an adaptationist theory to interpret fetal-->maternal microchimerism and the diverse set of concomitant medical phenomena. We handle fetal, maternal, and paternal adaptive interests separately and in interaction with one another. Fetuses may benefit from immunological information gathered by migrant cells in the maternal body, and also from improved maternal defence. However, they may be jeopardized by a selfish maternal usage of fetal-->maternal microchimerism - i.e., some mothers get pregnant only to improve their immune system and then to abort. The use of microchimeric cells by the maternal immune system may contribute to the adaptive benefits of female choosiness and polyandry. While fathers may enjoy an indirect benefit from enhanced fetal and maternal health, they also face the risk of wasting sexual efforts due to selfish pregnancies of cheating females. Paternal alleles acting via clones of microchimeric cells in the maternal body could launch an immunological attack against the non-kin sperm in the female genitalia, or against the non-kin fetus in the womb. Furthermore, an intraspecific version of Zahavi's Mafia Hypothesis could explain a potential interaction between the abortion of fetuses and a subsequent rise of an autoimmune disease. We suggest that males may be capable to provoke microchimerism-induced autoimmune-like diseases in the mother in revenge of selfish pregnancies. This hypothetic paternal threat could increase the maternal costs associated to selfish pregnancies. From a medical point of view, we propose new interpretations for autoimmune-like diseases, infertility, miscarriage, and also for the prevailing connections among them. Specifically, we argue that miscarriages may cause autoimmune diseases, a reversed causality as compared to the currently accepted one.  相似文献   
104.
When learning to master a visual task in a cluttered natural environment, it is important to optimize the processing of task-relevant information and to efficiently filter out distractors. However, the mechanisms that suppress task-irrelevant information are not well understood. Here we show that training leads to a selective increase in motion coherence detection thresholds for task-irrelevant motion directions that interfered with the processing of task-relevant directions during training. Furthermore, using functional magnetic resonance imaging we found that training attenuated neural responses associated with the task-irrelevant direction compared with the task-relevant direction in the visual cortical areas involved in processing of visual motion. The strongest suppression of functional magnetic resonance imaging responses to task-irrelevant motion information was observed in human area MT+. These findings reveal that perceptual learning leads to the suppression and efficient filtering of task-irrelevant visual information.  相似文献   
105.
A panel of international breast cancer experts formulated a declaration of consensus regarding many key issues in the use of primary systemic therapy (PST) either in clinical routine or research practice. The attainment of pathological complete response (pCR), defined as no residual invasive tumor in the surgical specimens both in breast and in axillary nodes, is one of the main goals of PST, and pCR can be used as the primary objective in prospective clinical trials. However, pCR is not a reliable endpoint with all treatment approaches, and alternatives such as Ki67 index of the residual invasive disease or after 2 weeks of PST are also potential endpoints. PST has several advantages: breast conservation and the unique opportunity to obtain information on the interaction between treatment and tumor biology. Changes in tumor biology after PST are an early phenomenon; so, an additional core biopsy performed after 14 days from treatment start should be considered in clinical trials.  相似文献   
106.

Background and purpose:

A peptide bradykinin (BK) B2 receptor agonist partially resistant to degradation, B-9972, down-regulates this receptor subtype. We have used another recently described non-peptide agonist, compound 47a, as a tool to study further the effects of metabolically more stable and thus persistent, agonists of the BK B2 receptor on signalling, desensitization and down-regulation of this receptor.

Experimental approach and key results:

Compound 47a was a partial agonist at the B2 receptor in the human umbilical vein, where it shared with B-9972 a very slow relaxation on washout, and in HEK 293 cell lines expressing tagged forms [myc, green fluorescent protein (GFP)] of the rabbit B2 receptor. Compound 47a desensitized the umbilical vein to BK. In the cellular systems, the inactivation-resistant agonists induced [Ca2+]i transients as brief as those of BK but affected other functions with a longer duration than BK [12 h; receptor endocytosis, endosomal β-arrestin1/2 translocation, protein kinase C-dependent extracellular signal-regulated kinases (ERK)1/2 phosphorylation and c-Fos expression]. The B2 receptor–GFP was degraded in cells exposed to B-9972 or compound 47a for 12 h. The non-peptide B2 receptor antagonist LF 16-0687 prevented all effects of compound 47a, which were also absent in cells lacking recombinant B2 receptors.

Conclusion and implications:

Inactivation-resistant agonists revealed a long-lasting assembly of the agonist–B2 receptor–β-arrestin complexes in endosomal structures and induce ‘biased signalling’ (in terms of activation of ERK and c-Fos) as a function of time. Further, B-9972 and compound 47a, unlike BK, efficiently down-regulated BK B2 receptors.  相似文献   
107.
Rheumatoid arthritis, in common with other systemic autoimmune diseases, can involve several other organs presenting with complex immunological manifestations. Immune thrombocytopenic purpura caused by an autoimmune reaction against platelets is an infrequent haematological complications. A female patient with rheumatoid arthritis rapidly developed extremely severe immune thrombocytopenic purpura upon suspending oral corticosteroid therapy. Besides the involvement of the mucosa of the coecum, ascending colon and the gastric antrum, the situation was further complicated by bleeding of a gastric polyp, at the nadir of the thrombocytopenic crisis. The bleeding was managed by endoscopic intervention and platelet count recovered upon high dose corticosteroid treatment within a couple of days.  相似文献   
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110.
Two cases of patent ductus arteriosus (PDA) and aortic stenosis are presented. Both were diagnosed at routine cardiac catheterization and significant aortic gradient was concomitantly encountered. The first patient had subacute bacterial endocarditis due to B. cereus infection. Eventually it was proven to be localized on the PDA on the pulmonary artery side. Both patients underwent closure of PDA through endopulmonary closure and aortic valve replacement. Postoperative courses were uneventful. These cases demonstrated the technically easy closure of the PDA in the elderly. The literature has documented only six cases including our two cases. (J Card Surg 1994;9:85–88)  相似文献   
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