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51.
Idiopathic thrombocytopenic purpura (ITP) is a heterogeneous bleeding disorder. The Intercontinental Childhood ITP Study Group (ICIS) analyzed demographic data and outcome in a prospective registry of over 2,000 children with ITP. In addition, participating centers from 12 different countries worldwide were asked to describe their local and cultural aspects of ITP management to provide a summary statement of the variable diagnostic and management approaches for childhood ITP. The statements of the 15 reports from 12 countries are summarized under eight main areas to reflect the variability in approach to ITP among different countries. The management of ITP in children differs dramatically worldwide in terms of observation only, medical treatment, bleeding symptoms, acceptable platelet counts, need for hospitalization or outpatient treatment, and medical care climate. The majority of experimental treatments, surveys, and guidelines are not evidence-based. Although there is a great need for cooperative studies to learn more about diagnosis, management, and prognosis in the heterogeneous disorder of ITP, local and cultural variations must be considered in international investigations. 相似文献
52.
This report describes a newborn with a cervical esophageal duplication cyst, a rare developmental anomaly of the neck. Only a few cases of this cystic entity have been described in the literature to date. This case is unique in that the patient had an air-fluid level within the lesion as a result of communication of the duplication cyst with the native esophagus. 相似文献
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Background/Purpose: Epidermal growth factor (EGF) and its receptor (EGFR) are key components in the genesis of adaptation after small bowel resection (SBR). Within intestinal homogenates, EGFR expression is increased after SBR; however, the exact cells responsible for altered EGFR expression are unknown. In this study, laser capture microdissection (LCM) microscopy was used to elucidate the specific cellular compartment(s) responsible for postresection changes in EGFR expression. Methods: Male ICR mice underwent a 50% proximal SBR or sham operation. After 3 days, frozen sections were taken from the remnant ileum. Individual cells from villi, crypt, muscularis, and mesenchymal compartments were isolated by LCM. EGFR mRNA expression for each cell compartment was quantified using real-time polymerase chain reaction (PCR). Results: EGFR expression was increased after SBR within the crypt (2-fold) and muscularis compartments (3-fold). There were no changes detected after SBR in the villus tips or mesenchymal compartments. Conclusions: Increased expression of EGFR in crypts directly correlates with the zone of cell proliferation and supports the hypothesis that EGFR signaling is crucial for the mitogenic stimulus for adaptation. The finding of increased EGFR expression in the muscular compartment is novel and may implicate a role for EGFR as a mediator of the muscular hyperplasia seen after massive SBR. J Pediatr Surg 38:440-445. 相似文献
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Intelligibility of sentences recorded from the uterus of a pregnant ewe and from the fetal inner ear
The intelligibility of sentences recorded from the uterus of a pregnant ewe and from the near-term fetal sheep inner ear was judged by 30 listeners. Sentences were presented to the ewe at 95 and 105 dB SPL while sequential recordings of sound with a hydrophone and a cochlear microphonic (CM) with electrodes were made. Recordings were randomized and presented to listeners to judge the intelligibility of sentences processed through the ewe and fetal inner ear. Intelligibility scores were nearly 99% for air and uterus conditions, dropped to 73% for CM ex utero and to 41% for CM in utero. Results indicated that filtering provided by the tissues and fluids of the maternal abdomen did not affect sentence intelligibility significantly, but the filtering effects as the signal passed into the fetal inner ear resulted in much poorer intelligibility. 相似文献
58.
Jarboe MD Juno RJ Stehr W Bernal NP Profitt S Erwin CR Warner BW 《Journal of pediatric surgery》2005,40(1):92-97
Background/Purpose
Intestinal adaptation is a compensatory response to massive small bowel loss in which there are increased numbers of absorptive enterocytes. However, the generation of secretory epithelial cell subtypes in this process has not been investigated. The purpose of this study was to examine the adaptive changes of several small intestinal cell lineage changes in response to massive small bowel resection (SBR).Methods
A 75% SBR or sham operation was performed on male Sprague-Dawley rats. On postoperative day 7, the remnant ileum was harvested and immunohistochemical staining for goblet, Paneth, and enteroendocrine cells was performed. Cell subtypes were evaluated as cells per micrometer of villus/crypt length and compared among operations.Results
A significant increase in goblet cell density occurred after SBR. Intestinal resection did not alter the number of Paneth and enteroendocrine cells. In additional experiments, inhibition of epidermal growth factor receptor signaling was associated with a diminished goblet cell density.Conclusions
The adaptive response of the intestine to massive bowel loss results in an expansion of the goblet cell population in addition to greater numbers of absorptive enterocytes. Although the mechanism and purpose for selective expansion of these stem cell-derived lineages are not presently known, epidermal growth factor receptor signaling appears to be a common pathway. 相似文献59.
Umut Disel Russell Madison Kumar Abhishek Jon H. Chung Sally E. Trabucco Asli O. Matos Garrett M. Frampton Lee A. Albacker Venkataprasanth Reddy Nuri Karadurmus Adam Benson Jennifer Webster Semra Paydas Ruben Cabanillas Chaitali Nangia M.A. Ozturk Sherri Z. Millis Sumanta K. Pal Breelyn Wilky Ethan S. Sokol Laurie M. Gay Salil Soman Shridar Ganesan Katherine Janeway Phil J. Stephens Viola W. Zhu Sai-Hong Ignatius Ou Christine M. Lovly Mrinal Gounder Alexa B. Schrock Jeffrey S. Ross Vincent A. Miller Samuel J. Klempner Siraj M. Ali 《The oncologist》2020,25(1):e39-e47
60.
Clinical utility of the reticulocyte hemoglobin content in the diagnosis of iron deficiency 总被引:8,自引:0,他引:8 下载免费PDF全文
Determination of the reticulocyte hemoglobin content (CHr) provides an early measure of functional iron deficiency because reticulocytes are the earliest erythrocytes released into blood and circulate for only 1 to 2 days. The CHr in 78 patients undergoing bone marrow examination was measured to assess its clinical utility for the diagnosis of iron deficiency. Twenty-eight patients were iron deficient, based on the lack of stainable iron in the aspirate. The diagnostic power of CHr is limited in patients with high mean cellular volume (MCV) or red cell disorders such as thalassemia. However, when patients with MCV more than 100 fL are excluded, receiver operator curve analysis of CHr, ferritin, transferrin saturation, and MCV demonstrates that CHr has the highest overall sensitivity and specificity of these peripheral blood tests for predicting the absence of bone marrow iron stores. 相似文献