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81.

Objective

To assess the value of multiplanar reformation (MPR) and three-dimensional multidetector computed tomography (MDCT) images in evaluating respiratory distress in neonates.

Materials and methods

Sixteen neonates (?30 days) who presented with respiratory distress (RD) and admitted in the neonatal intensive care unit of the Assuit university children hospital who were selected from a total of 1295 patients presented with RD in whom chest X-ray was inconclusive, so those 16 neonates underwent 64-rows MDCT in the period between November 2010 and November 2011. The recruited patients were sedated before examination and IV contrast medium administration was needed when there was suspected vascular anomaly. Scans were performed in supine position to cover the root of the neck down to the level of the adrenal glands. The images were sent to the workstation to be reviewed in the multiplanar and 3D images.

Results

The final radiologic diagnoses included cystic adenomatoid malformation (n = 4, 25%), congenital lobar emphysema (= 1, 7%), pneumonia (n = 5, 36%), hypoplastic lung (= 3, 22%), diaphragmatic hernia (n = 2, 14%) and postoperative hydro-pneumothorax (= 1, 7%).

Conclusion

The combination of fast speed, high spatial resolution, and enhanced quality of MPR and 3D images makes MDCT an ideal non-invasive method for evaluating surgical causes of neonatal respiratory distress.  相似文献   
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Previous work has suggested that the peptide corticotropin-releasing factor (CRF) acts to inhibit visually guided feeding in anurans, but little is known about potential targets for CRF within the subcortical visuomotor circuitry. Here we investigated the relationship between CRF neuronal organization and visual pathways in toads. CRF-immunoreactive (ir) neurons and fibers were widely distributed throughout the ventral subpallial telencephalon and hypothalamus, although few fibers were found in telencephalic areas, such as the striatum, that are known to project to the tectum in anurans. Large populations of CRF-ir cells were observed in the bed nucleus of the stria terminalis and preoptic area as well as in the ventral infundibular hypothalamus. CRF-ir neurons and fibers also were observed in several midbrain and brain stem areas. Colchicine treatment significantly enhanced CRF-ir neurons and fibers throughout the brain, and revealed CRF-ir cell groups in several brain areas (including the dorsal hypothalamus) that were not observed in untreated animals. Intrinsic CRF-immunoreactive neurons were routinely observed in cell layer 8 and sometimes in layer 6 of the optic tectum in both untreated and colchicine-treated animals. CRF was detected in toad optic tectum by radioimmunoassay, although tectal CRF content was less than that of the hypothalamus and forebrain. Unilateral eye ablation did not affect CRF content of the contralateral optic tectum. We conclude that CRF-producing neurons are widely distributed in several areas of the toad brain known to be involved in regulating the behavioral, autonomic and endocrine response to stressors, including the optic tectum and several brain areas known to project to the optic tectum. Furthermore, retinal afferents do not contribute significantly to tectal CRF content.  相似文献   
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The temporal effects of oral administration of cyproterone acetate (CPA), a progestational androgen receptor blocker, were studied on the fertility of adult male rat sires, at a dose of 20 mg kg-1 day-1 after 15 days of gavage. The treatment reduced the fertility and weights of accessory sex glands, without altering the serum levels of luteinizing hormone, follicle-stimulating hormone (FSH) and testosterone (T). Sperm counts were significantly reduced after treatment. Several changes were evident in caput epididymal sperm chromatin in treated rats. The in vitro decondensation rates of sperm chromatin and total fluorescent acridine orange (AO) dye uptake were enhanced. The fluorescent AO dye uptake by the double- and single-stranded sperm chromatin increased. The uptake of thiol-specific monobromobimane fluorescent dye by sperm chromatin was significantly reduced. Sperm of treated rats exhibited hypoprotamination. Protamine levels in the testis were significantly reduced after treatment. Androgen-binding protein (ABP) expression was significantly reduced in testis after treatment. A slight but significant increase was observed in cyclic AMP immunoexpression in testis after treatment. The expression and levels of transition proteins 1 (TP1) and 2 (TP2) as well as cyclic AMP response element modulator protein-tau were maintained at control levels in the testis of treated rats. The present study reports that androgen receptor occupation by CPA preferentially reduces the levels of spermatidal protamine in testis and spermatozoa involved in nuclear chromatin condensation. It is inferred that ABP could be mediating the effects of T in modulating the sequential expression of TPs and protamines during nuclear chromatin condensation. It is likely that indirect effects of T involve its aromatization in spermatids.  相似文献   
85.
Stress and stress hormones affect a variety of behaviors and cognitive abilities. The influences of stress and glucocorticoids on motor function, however, have not been characterized although the presence of glucocorticoid receptors in the motor system has been documented. Here we demonstrate that stress and the stress hormone corticosterone influence motor system function in rats. Groups of adult female Long-Evans rats underwent either a daily stress-inducing procedure (immobilization or swimming in cold water) or oral corticosterone treatment. While these treatments continued, animals were tested in skilled reaching and skilled walking tasks for a period of 2 weeks. Both acute (day 1) and chronic (day 14) stress and corticosterone treatment reduced skilled movement accuracy in reaching and walking and increased performance speed. Furthermore, both chronic stress and chronic corticosterone treatment altered skilled movement patterns in the reaching task. These findings indicate that stress modulates motor system function and that these effects are partially mediated by glucocorticoids. To examine whether stress-induced changes might also derive from enhanced emotionality, rats were treated with the benzodiazepine diazepam. Based on an inverted U-shaped dose-response relationship, a moderate dose of diazepam significantly improved reaching success while at the same time reducing corticosterone levels. Thus, stress-associated emotional responses such as anxiety might account for diminished movement accuracy. These results suggest that stress affects the motor system both directly via hormonal changes and indirectly via changes in emotionality. These findings are discussed with respect to the role of stress in motor system function and movement disorders.  相似文献   
86.
Image-guided core biopsy of the omentum and peritoneum was described a decade ago and has since been validated in a number of large studies as a safe and effective means of providing a tissue diagnosis in patients with undiagnosed peritoneal disease. Some studies have addressed its ability for determining whether peritoneal infiltration and/or omental masses in patients with prior malignancy represent recurrent disease or a new disease process. Others have focused on the specific issue of women suspected to have advanced peritoneal carcinomatosis from ovarian or primary peritoneal cancer where the primary management of the patient is directed by the tissue diagnosis. The initial management of many of these women, especially those with advanced disease or substantial comorbidity, is with primary chemotherapy. With current clinical trials for ovarian cancer directed to specific morphological subtypes of the disease, image-guided core biopsy offers a rapid and well tolerated nonsurgical means of providing this information. In this Review, we discuss the technique and its clinical applications, and critically examine the currently available alternative options.  相似文献   
87.
A growing body of evidence suggests that neurotrophins (NTs) play a critical role in synaptic plasticity and other activity dependent processes in the CNS. Release of these growth factors by neurons and neuroendocrine cells was recently shown to occur via the regulated secretory pathway, representing a possible mechanism for preferentially supplying NTs locally to active synapses. However, the identity and characteristics of the intracellular storage compartment for NTs undergoing stimulus-coupled secretion remains controversial. As a step towards addressing these issues we have investigated the subcellular localization of epitope-tagged nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurotrophin-3 (NT-3) in neuroendocrine cells. Placement of the myc-epitope tag at the neurotrophin carboxy terminus did not affect essential properties of the NTs such as their ability to induce Trk tyrosine phosphorylation or their sorting into the regulated secretory pathway in PC12 and AtT-20 neuroendocrine cells. Epitope-tagged NTs colocalize with dense core vesicle (DCV)-markers at the light microscopic level in both cell lines investigated. Furthermore, at an EM level immunoreactivity (IR) for myc-tagged NGF was found over dense core granules (DCGs) in PC12 cells. These data provide evidence that NTs can be stored in DCVs in neuronal model cell lines and, potentially, in neurons as well. J. Neurosci. Res. 51:463–472, 1998. © 1998 Wiley-Liss, Inc.  相似文献   
88.
This study examined the knowledge and practices of adolescent school girls in Kano, Nigeria around menstruation and menstrual hygiene. Data was collected quantitatively and analyzed using Epi info version 3.2.05. The mean age of the students was 14.4 +/- 1.2 years; majority was in their mid adolescence. The students attained menarche at 12.9 +/- 0.8 years. Majority had fair knowledge of menstruation, although deficient in specific knowledge areas. Most of them used sanitary pads as absorbent during their last menses; changed menstrual dressings about 1-5 times per day; and three-quarter increased the frequency of bathing. Institutionalizing sexuality education in Nigerian schools; developing and disseminating sensitive adolescent reproductive health massages targeted at both parents and their adolescent children; and improving access of the adolescents to youth friendly services are veritable means of meeting the adolescent reproductive health needs in Nigeria.  相似文献   
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