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Atrioventricular block may occasionally occur after surgical correction of truncus arteriosus. We therefore studied the conduction system by means of serial sections in five cases of truncus (one after surgical intervention) to delineate the course of the conduction system and its relationship to the ventricular septal defect and the membranous septum. In general, the ventricular septal defect is in the anterior septum, confluent with the truncus, and the atrioventricular bundle is posterior and unrelated to the rim of the ventricular septal defect. In cases in which the ventricular septal defect is anterior and separated from the membranous septum by distinct muscle, the ventricular septal defect can be surgically closed without injury to the atrioventricular bundle. If the ventricular septal defect is related to the membranous septum, the atrioventricular bundle may be close to the ventricular septal defect and susceptible to surgical injury. If muscle separates the ventricular septal defect from the membranous septum, the branching bundle is close to the ventricular septal defect and also is susceptible to surgical injury. In one operated case there was partial dissolution of the left bundle branch, and the right bundle branch was involved in surgical closure of the defect. In summary, in truncus the conduction system varies in its course and is related to the location of the ventricular septal defect and its relationship to the membranous septum. The ventricular septal defect may be close to or related to the membranous septum, and the atrioventricular bundle and the beginning of the bundle branches may be vulnerable to surgical injury.  相似文献   
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In the present study, the requirements and characteristics forthe production of IL-13 by human T cells, T cell clones andB cells were determined and compared with those of IL-4. IL-13was produced by human CD4+ and CD8+ T lymphocyte subsets isolatedfrom peripheral blood mononuclear cells and by CD4+ and CD8+T cell clones. CD4+ T cell clones belonging to Th0, Th1-likeand Th2-like subsets produced IL-13 following antigen-specificor polyclonal activation. In addition, EBV-transformed B celllines expressed IL-13 mRNA and produced small amounts of IL-13protein. Expression of IL-13 mRNA and production of IL-13 proteinby peripheral blood T cells and T cell clones was induced rapidlyand was relatively long lasting, whereas IL-4 production bythese cells was transient In addition, IL-13 mRNA expressionwas induced by modes of activation that failed to induce IL-4mRNA expression. IL-13 shares many biological activities withIL-4 which Is compatible with the notion that the IL-13 andIL-4 receptors share a common component required for signaltransduction. However, IL-13 lacks the T cell-activating propertiesof IL-4. Here we have shown that this is related to the factthat T cells fall to bind radiolabeled IL-13 and do not expressthe IL-13-speclflc receptor component Taken together, theseresults indicate that the differences In expression and biologicalactivities of IL-4 and IL-13 on T cells may have consequencesfor the relative roles of these cytokines In the immune response.  相似文献   
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Widespread use of prophylactic colectomy has resulted in a reduction in the incidence of colorectal cancer in familial adenomatous polyposis (FAP) patients. A retrospective chart review of families registered at the Steve Atanas Stavro Familial Gastrointestinal Cancer Registry in Toronto was performed to determine whether the decrease in the number of patients developing colorectal cancer implies that causes of mortality in FAP patients are shifting to that of extracolonic manifestations of FAP. Information was available on 140 deaths within 158 families and among 461 individuals with FAP. When stratified by decade, from the 1930s to the 1990s, the ratio of deaths caused by extracolonic manifestations of FAP compared with deaths caused by colorectal cancer was noted to have risen. Even though most deaths in FAP patients are still from colorectal cancer, it appears that screening policies and prophylactic colectomy have resulted in a reduction in the number of FAP patients who develop colorectal cancer. Thus, in recent decades, a greater percentage of deaths in FAP patients appears to be attributable to extracolonic manifestations of the disease.  相似文献   
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Backgroundmidwifery is a part of the nursing profession in India. This current study explores and describes the midwifery scope of practice among staff nurses.Methodsa grounded theory approach was used to develop a model. Twenty-eight service providers from the maternity sections of public health facilities, selected through purposive and theoretical sampling were interviewed in-depth. Unstructured observations in the labour wards were also used for developing the model.Findingsthe midwifery practice of staff nurses was limited in scope compared to international standards of midwifery. Their practice was circumstance driven, ranging from extended to marginal depending on the context. Their right to practice was not legally defined, but they were not specifically prohibited from practice. As a consequence, the staff nurses faced loss of skills, and deskilling when their practice was restricted. Their practice was perceived as risky, when the scope of practice was extended because it was not rightfully endorsed, the nurses having no officially recognized right to practice midwifery at that level. The clinical midwifery education of nursing and midwifery students was marginalized because the education of medical students was given priority, and the students only got exposed to the restricted practice of staff nurses.Conclusionsunclear definitions of the right to practice and the scope of practice have led to the un-utilized potential of staff nurses practising midwifery. This is detrimental because India faces an acute shortage of qualified personnel to meet the need in providing human resources for maternal health.  相似文献   
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Ocular involvement of rhinosporidiosis is seen in about 15% of cases and clinically appears as a freely mobile, granular, pink, fleshy sessile or pedunculated mass. The conjunctiva is the most common site of origin. A 25-year-old male presented with a painless mass in the lower part of the left eye for 6 months which was gradually progressive. Examination revealed a pedunculated mass of 15 mm x 15 mm arising from the lower palpebrae of the left eye retracting the lower lid. It appeared to be vascular with few white spots at the apex. Rest of the ocular examinations was within the normal limit. The presentations of ocular rhinosporidiosis vary. Though the conjunctival origin is very common, it may not have a classic pink fleshy appearance at all times. A vascular/cystic painless conjunctival mass should also be considered as a case of rhinosporidiosis in prone areas.  相似文献   
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The potent orexigenic peptide neuropeptide Y (NPY) has been considered as a possible endogenous ligand for a subpopulation of sigma receptors (SigR). However, their mutual interaction with reference to feeding behavior remains poorly understood. In the present study, we explored the possible interaction between sigma1 receptors (Sig1R) agonist, pentazocine, and NPY on food intake in satiated rats. While pentazocine dose-dependently reduced the food intake, NPY significantly increased it at 2, 4 and 6 h post injection time points. In combination studies, pretreatment with NPY (0.1 nmol/rat, intra-PVN) normalized the inhibitory effect of pentazocine (60 μg/rat, intra-PVN) on food intake. Similarly, pre-treatment with pentazocine (30 μg/rat, intra-PVN) significantly antagonized the orexigenic effect of NPY (0.5 and 1.0 nmol/rat, intra-PVN). Moreover, pentazocine treatment decreased NPY immunoreactivity in arcuate (ARC), paraventricular (PVN), dorsomedial (DMH) and ventromedial (VMH) nuclei of hypothalamus. However, no change was observed in lateral hypothalamus (LH). Study implicates the reduced NPY immunoreactivity for the anorectic effect observed following pentazocine injections. Therefore, the concomitant activation of the NPYergic system along with the Sig1R agonist treatment may serve a useful purpose in the management of the unwanted side effects related to energy homeostasis.  相似文献   
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Clinical and angiographic or autopsy data, or both, on three children with a subdivided left atrium (cor triatriatum) and an associated endocardial cushion defect are reviewed. (One child had ostium primum defect, and two had complete atrioventricular [A-V] canal.) A fourth patient demonstrates the difficulties in differentiating subdivided left atrium from supravalve mitral stenosis in the presence of an endocardial cushion defect. The clinical findings are greatly influenced by the endocardial cushion defect. A pressure gradient between the pulmonary wedge and (left or right) ventricular end-diastolic pressures in patients with an endocardial cushion defect indicates pulmonary venous obstruction and should alert one to the possibility of these combined lesions. The exact diagnosis is made with injections of angiographic contrast medium into the proximal and distal left atrial chambers, to document the respective relations of the pulmonary veins, left atrial appendage and A-V valves to these atrial chambers. All three patients with an endocardial cushion defect and a subdivided left atrium had an associated patent ductus arteriosus. The common association of subdivided left atrium with intracardiac, pulmonary venous and aortic anomalies is again demonstrated.  相似文献   
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