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排序方式: 共有691条查询结果,搜索用时 31 毫秒
81.
Of 433 febrile children examined in the paediatric clinics of two university hospitals in Tehran, Iran, 39 (9%) children (27 girls and 12 boys) were diagnosed as having urinary tract infection in which Escherichia coli was the most frequently detected pathogen (84.6%). According to the voiding cystourethrogram, nine (75%) boys and 17 (63%) girls had urinary tract abnormalities. This result is slightly higher than seen in other reports from developing countries. 相似文献
82.
Syncope is a transient loss of consciousness and postural tone, with spontaneous recovery, and may represent an episode of aborted cardiac arrest. The final common pathway for loss of consciousness from non-neurologic causes is hypoperfusion of the reticular activating system. The etiology of syncope in older patients frequently includes a myriad of causes (e.g., orthostatic hypotension, medication side effects, sick sinus syndrome, atrioventricular block, carotid hypersensitivity, ventricular tachycardia, and aortic stenosis). Initial evaluation must include a detailed history, complete physical examination, and 12-lead ECG, which provides a framework as to the probable cause of syncope in approximately 40% of patients. Echocardiography, electrophysiology testing, and head-upright tilt table testing will confirm the diagnosis in most of the remainder. Approximately 25% of patients will have no identifiable cause of syncope, but have a better prognosis than patients with a confirmed cardiac cause of syncope. Treatment is directed at the underlying cause. 相似文献
83.
Trophoblast differentiation in embryoid bodies derived from human embryonic stem cells 总被引:8,自引:0,他引:8
Gerami-Naini B Dovzhenko OV Durning M Wegner FH Thomson JA Golos TG 《Endocrinology》2004,145(4):1517-1524
Trophoblast differentiation and early placental development are essential for the establishment of pregnancy, yet these critical events are not readily investigated in human pregnancy. We used embryoid bodies (EBs) prepared from human embryonic stem (hES) cells as an in vitro model of early human development. The levels of human chorionic gonadotropin (hCG), progesterone, and estradiol-17beta in medium from hES cell-derived EBs grown in suspension culture for 1 wk were higher than unconditioned culture medium or medium from undifferentiated hES cells or spontaneously differentiated hES cell colonies. EBs were explanted into Matrigel (MG) "rafts" and cultured for up to 53 d. During the first 7-10 d of three-dimensional growth in MG, small protrusions appeared on the outer surface of EBs, some of which subsequently extended into multicellular outgrowths. The secretion of hCG, progesterone, and estradiol-17beta began to increase on approximately d 20 of MG culture and remained dramatically elevated over the next 30 d. EBs maintained in suspension culture failed to demonstrate this elevation in hormone secretion. Suspension-cultured and MG-embedded EBs exhibited widespread expression of cytokeratins 7/8, demonstrating extensive epithelial differentiation as well as consistent hCG expression. We propose that hES cell-derived EBs may be a useful model for investigation of human trophoblast differentiation and placental morphogenesis. 相似文献
84.
Multimodality noninvasive imaging demonstrates in vivo cardiac regeneration after mesenchymal stem cell therapy. 总被引:4,自引:0,他引:4
Luciano C Amado Karl H Schuleri Anastasios P Saliaris Andrew J Boyle Robert Helm Behzad Oskouei Marco Centola Virginia Eneboe Randell Young Joao A C Lima Albert C Lardo Alan W Heldman Joshua M Hare 《Journal of the American College of Cardiology》2006,48(10):2116-2124
OBJECTIVES: The purpose of this study was to test the hypothesis, with noninvasive multimodality imaging, that allogeneic mesenchymal stem cells (MSCs) produce and/or stimulate active cardiac regeneration in vivo after myocardial infarction (MI). BACKGROUND: Although intramyocardial injection of allogeneic MSCs improves global cardiac function after MI, the mechanism(s) underlying this phenomenon are incompletely understood. METHODS: We employed magnetic resonance imaging (MRI) and multi-detector computed tomography (MDCT) imaging in MSC-treated pigs (n = 10) and control subjects (n = 12) serially for a 2-month period after anterior MI. A sub-endocardial rim of tissue, demonstrated with MDCT, was assessed for regional contraction with MRI tagging. Rim thickness was also measured on gross pathological specimens, to confirm the findings of the MDCT imaging, and the size of cardiomyocytes was measured in the sub-endocardial rim and the non-infarct zone. RESULTS: Multi-detector computed tomography demonstrated increasing thickness of sub-endocardial viable myocardium in the infarct zone in MSC-treated animals (1.0 +/- 0.2 mm to 2.0 +/- 0.3 mm, 1 and 8 weeks after MI, respectively, p = 0.028, n = 4) and a corresponding reduction in infarct scar (5.1 +/- 0.5 mm to 3.6 +/- 0.2 mm, p = 0.044). No changes occurred in control subjects (n = 4). Tagging MRI demonstrated time-dependent recovery of active contractility paralleling new tissue appearance. This rim was composed of morphologically normal cardiomyocytes, which were smaller in MSC-treated versus control subjects (11.6 +/- 0.2 mum vs. 12.6 +/- 0.2 mum, p < 0.05). CONCLUSIONS: With serially obtained MRI and MDCT, we demonstrate in vivo reappearance of myocardial tissue in the MI zone accompanied by time-dependent restoration of contractile function. These data are consistent with a regenerative process, highlight the value of noninvasive multimodality imaging to assess the structural and functional basis for myocardial regenerative strategies, and have potential clinical applications. 相似文献
85.
ObjectivePersonal identification is an essential issue when mutilated and amputated limbs or parts of the body are found in mass disasters. Estimation of the stature from the size of different parts of the body is one of the most important items in personal identification. The aim of this study was to estimate the stature from upper limb anthropometry.Materials and methodsHeight, left upper limb, left arm, left forearm, length and breadth of the left hand, and length of the left second to fifth fingers were measured on 100 right-handed Iranian medical students aged between 21 and 26 years from February to may 2010.ResultsAfter analyzing the datas, it was shown that there is a meaningful relation between the stature and upper limb dimensions (p < 0.05), [correlation coefficients ranged from 0.310 to 0.696 in males and 0.299 to 0.735 in females].ConclusionThe regression formula derived in this study can be used for forensic pathologists and Anthropologists. 相似文献
86.
Karami H Javanmard B Hasanzadeh-Hadah A Mazloomfard MM Lotfi B Mohamadi R Yaghoobi M 《Journal of endourology / Endourological Society》2012,26(9):1183-1186
Abstract Purpose: To assess the necessity of placing a ureteral stent after transperitoneal laparoscopic ureterolithotomy (TPLU). Patients and Methods: In the period from May 2006 to November 2010, 46 patients underwent TPLU. There were 13 females and 33 males. All patients had an impacted stone larger than 1.5?cm in the upper and middle parts of the ureter. TPLU was performed as either a primary therapy or as a salvage therapy in patients in whom another treatment had failed. The exclusion criteria were pregnancy, a body mass index more than 35, and patients with abnormal results on coagulative tests. In all cases, after removing the stone, the ureter was sutured. In the first 23 patients, no ureteral catheter was placed, but in the second 23 patients, a Double J catheter was inserted through the ureter. Results: In one case, the stone was pushed back. The stone-free rate was 97.8%. There were four cases of prolonged urinary leakage after the surgery. All of them were in the group in whose members the Double J catheter had not been placed. The problem was resolved in one patient spontaneously after 4 days, but for the other three patients, a Double J catheter was placed and the leakage was stopped in 24 hours. There was no case of urinary leakage in the second group of patients with a placed Double J catheter. Conclusion: Placing a Double J catheter during surgery does not increase the time of operation and may play a role in prevention of urinary extravasation after laparoscopic ureterolithotomy. 相似文献
87.
Cutaneous and histopathological features of coronavirus disease 2019 in pediatrics: A review article
Maryam Khalili Behzad Iranmanesh Saman Mohammadi Mahin Aflatoonian 《Dermatologic therapy》2021,34(1):e14554
Prevalence of dermatological manifestations of coronavirus disease 2019 (COVID‐19) is estimated between 0.25% and 3% in children and adolescents. In this review article, we decided to describe the cutaneous and histopathological manifestations of COVID‐19 infection in pediatrics. We searched published articles in PubMed database for key words of “children” or “pediatric” and “cutaneous” or “dermatology” or “skin” and “COVID‐19” or “SARS‐CoV‐2” or “Coronavirus disease 2019” in abstract or title from December of 2019 until September 2020. Finally, 38 articles were selected. The majority of patients were between 11 and 17 years old with predominantly male gender. Most of the patients were either asymptomatic or had a few general symptoms. The latency time from appearance of general symptoms to cutaneous ones was between 1 day and weeks. Skin lesions faded between 3 and 88 days without any sequelae, spontaneously or with either topical or systemic corticosteroids. Skin manifestations were chilblain‐like (pseudochilblain), erythema multiforme‐like, dactylitis, acral erythema, acute urticaria, livedo reticularis, mottling, acro‐ischemia, generalized maculopapular lesions, eyelid dermatitis, miliaria‐like, varicelliform lesions, and petechiae and/or purpura. Kawa‐COVID‐19 patients were presented more frequently with cardiogenic shock, neurological symptoms, lymphocytopenia, and thrombocytopenia as compared to classic Kawasaki's disease. Furthermore, more number of cases were resistant to the first‐line treatments. 相似文献
88.
Aplin John D.; Spanswick Catherine; Behzad Farhad; Kimber Susan J.; Vicovac Ljiljana 《Molecular human reproduction》1996,2(7):527-534
Several adhesion molecules have been shown to occur at the surfaceof endometrial cells. One of these is the integrin 相似文献
89.
90.