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941.
942.
CD34/CD117 co-expression in childhood acute leukemia 总被引:3,自引:0,他引:3
Uçkan D Hiçsönmez G Yetgin S Gürgey A Cetin M Karaağaoğlu E Okur H Tuncer AM 《Leukemia research》2000,24(3):201-206
CD117 protein is expressed by the primitive CD34 positive haemopoietic stem cells and also demonstrated on the blasts of 30-100% of AML cases, but rarely on lymphoblasts. Therefore several investigators have used CD117 expression to exclude lymphoblastic origin of blasts. However, conflicting results exist in the literature. We investigated CD34 and CD117 status at initial presentation of 232 children with acute leukemia. CD34 was commonly expressed in all types of acute leukemias, whereas CD117 molecule seemed to be a more specific marker for leukemia of myeloid origin being demonstrated on > 5% of blasts in 60 out of 73 cases of AML patients, but rarely detected in ALL (9/140 patients). Moreover, co-expression of CD34/CD117 was extremely rare on lymphoblasts with only 3/140 ALL patients demonstrating > 5% co-expression of CD34 and CD117, and therefore we suggest that it should be used in the exclusion of ALL. 相似文献
943.
Akyüz C Emir S Akalan N Söylemezoğlu F Kutluk T Büyükpamukçu M 《Acta oncologica (Stockholm, Sweden)》2000,39(1):97-100
Of the 818 tumours of the central nervous system diagnosed between 1972 and 1991, 62 patients (35 males and 27 females) with histopathologically confirmed ependymomas were treated and followed-up at the Children's Hospital of Hacettepe University during that period. The median age was 6 years (range 1-17 years). Headache, nausea and vomiting were the most frequent symptoms; papilledema was the most common sign in our patients. Tumour sites were in the posterior fossa in 47 patients and supratentorial in 15 patients. All patients underwent surgery. Gross- total resection was performed in 27 patients, subtotal resection in 32 patients and biopsy in the remaining 3 patients. Initially, 53 patients were given postoperative radiotherapy. Four patients did not receive radiotherapy because of their young age, whereas five patients died prior to starting radiotherapy. Two slightly different types of chemotherapy protocols were applied for an average of one year in 47 patients. Event-free and overall survival rates at 10 years were 36% and 50%, respectively. Twenty children suffered relapse 4 to 55 months after diagnosis (median 16 months). Relapses were distant in 3 cases and local in 17. Age was the only statistically significant prognostic factor, patients younger than 5 years of age having a poorer outcome. Sex, histopathologic type, localization of the tumour, extent of surgery, and chemotherapy did not influence the prognosis in our study. Because the majority of recurrences were local, better local tumour control is required. New treatment strategies should be developed in order to improve local control. 相似文献
944.
The expression of fragile sites in lymphocytes of patients with rectum cancer and their first-degree relatives 总被引:3,自引:0,他引:3
The present study was designed to clarify the molecules responsible for peritoneal dissemination of cancer cells. We established sublines with high (HP cells) and low (LP cells) passing activity through the membrane of a transwell chamber. The cell lines were established from the human pancreatic cancer cell line, Panc-1. LP cells demonstrated an octagonal shape and tight adhesion, whereas HP cells exhibited a spindle shape and grew with less cell-cell contact in vitro. It was found that HP cells demonstrated a high degree of peritoneal dissemination in nude mice following peritoneal injection of these cells compared to LP cells. We subsequently investigated the expression of certain adhesion molecules. Consequently, we found that LP cells exhibited a stronger expression of E-cadherin than HP cells. On the other hand, there was no difference in the expression of CD44H and beta1 integrin between these two sublines. Passing activity of LP cells through the membrane of the invasion chamber increased to nearly equal levels with HP cells following treatment with anti-human E-cadherin antibody. Moreover, transfection of mouse E-cadherin cDNA into HP cells reduced both passing activity through the membrane of the invasion chamber and peritoneal dissemination in nude mice to levels similar to that of LP cells. In conclusion, these results indicated that loss of E-cadherin facilitates both passing activity in an invasion chamber and peritoneal dissemination, playing a causative role in peritoneal dissemination of cancer cells. 相似文献
945.
Stary Z. Erez N. Bodur H. Anhegger-Lisie S. G. Çepeğlolu R. 《Archives of gynecology and obstetrics》1954,184(2):330-336
Archives of Gynecology and Obstetrics - Die Vermehrung der Serumpolysaccharide durchläuft während der Schwangerschaft 2 Phasen: Im 8. Schwangerschaftsmonat beginnt zunächst eine... 相似文献
946.
Extragonadal germ cell tumors: clinicopathologic findings, staging and treatment experience in 14 patients 总被引:2,自引:0,他引:2
Berkmen F Peker AF Ayyildiz A Başay S Arik AI Uğur I 《Journal of experimental & clinical cancer research : CR》2000,19(3):281-285
Extragonadal germ cell tumors (EGCT) are a rare group of neoplasms histologically identical to testicular counterparts. Fourteen cases of primary mediastinal and retroperitoneal germ cell tumors were treated with chemotherapy and radiotherapy between 1987 and 1999 in Ankara Oncology Hospital. There were 9 (64%) complete remissions (CR),one (7%) partial remission (PR) and 2 (14%) stable diseases (SD). The remaining 2 patients were lost due to dissemination of disease. The median duration of response was 19 months. Our modified chemotherapeutic results were similar to original doses of PVB and BEP but toxicity was less. The neccesity of a uniform staging system and treatment programs are discussed. 相似文献
947.
A comparative evaluation of the Etest and the broth microdilution methods for antifungal susceptibility testing of 102 clinical yeast isolates against amphotericin B, fluconazole, itraconazole, and ketoconazole was conducted. The agreements between the Etest and the broth microdilution methods were 93.1% for amphotericin B 85.2% for ketoconazole, 82.3% for itraconazole and 79.4% for fluconazole. These results suggest that the Etest approach to antifungal susceptibility testing may be a viable alternative to the NCCLS reference methods for testing yeasts, but that further evaluations are needed. 相似文献
948.
Antimicrobial resistance of gram-negative isolates from intensive care units in Turkey: comparison to previous three years 总被引:1,自引:0,他引:1
Yücesoy M Yuluğ N Kocagöz S Unal S Cetin S Calangu S 《Journal of chemotherapy (Florence, Italy)》2000,12(4):294-298
Resistance rates to selected antibiotics of gram-negative bacteria isolated from intensive care units (ICU) of 16 Turkish hospitals during 1998 were evaluated and compared to data from the previous 3 years. Antibiotic susceptibilities to imipenem, ceftazidime, ceftazidime-clavulanate, cefoperazone-sulbactam, ceftriaxone, cefepime, cefodizime, cefuroxime, piperacillin-tazobactam, ticarcillin-clavulanate, gentamicin, amikacin and ciprofloxacin were determined by Etest. A total of 1,404 isolates from 1,060 patients were collected, mainly from urinary and respiratory tracts. As in the previous 3 years, Pseudomonas spp. was the most frequently isolated gram-negative species (29.7%), followed by Escherichia coli, Acinetobacter and Klebsiella spp. Imipenem was the most active in vitro agent (73.4% susceptible), followed by ciprofloxacin (60.6%), cefoperazone-sulbactam (58.7%), cefepime (56.7%), piperacillin-tazobactam (55.0%) and amikacin (54.7%). In 1996, a decline in susceptibility rates of all antibiotics was evident. With the exception of imipenem, resistance to which remained stable, rates somewhat increased in 1997. In 1998, susceptibility to imipenem and cefepime remained stable, amikacin resistance tended to increase and susceptibility rates to other antibacterials showed a favorable increase. These results may in part be due to the implementation of a surveillance program and increased understanding of the magnitude of the resistance problem. 相似文献
949.
Nihat Demir Murat Başaranoğlu Zübeyir Huyut İbrahim Değer Kamuran Karaman M. Ramazan Şekeroğlu 《The journal of maternal-fetal & neonatal medicine》2019,32(9):1433-1440
Objective: To determine levels of trace elements [copper (Cu), zinc (Zn), selenium (Se), and cobalt (Co)] and heavy metals [arsenic (As), mercury (Hg), lead (Pb), and cadmium (Cd)] in the plasma of mothers and infants and investigate the relationship between those levels and neural tube defects (NTD).Methods: A total of 100 neonates diagnosed with NTD and placed in the Neonatal Intensive Care Unit of Yuzuncu Yil University, Turkey between May 2013 and December 2016 comprised the study group. The control group consisted of 70 healthy neonates not diagnosed with NTD or any other congenital anomalies. For both the groups, mother and infant plasma levels of Cu, Zn, Co, Cd, Se, Hg, As, and Pb were measured and compared. Plasma levels of Cu, Zn, Co, Cd, Se, Hg, As, and Pb were measured and compared between two groups of mothers and infants.Findings: Mother and infant plasma levels of trace elements Zn and Se were determined to be significantly lower in the study group compared with the control group, while Cu levels were significant elevated in the study group (all p values .05). Plasma levels of heavy metals As, Pb, and Cd were found to be significantly higher in the NTD control group (p?.05 for all). There was no association between maternal infection, maternal smoking status, history of miscarriage, or history of NTD with the development of NTD (p?>?.05). Differences in maternal age, birth weight, length of gestation, and infant gender for the two groups were also determined not to be statistically significant.Results: High plasma levels of heavy metals As, Pb, and Cd and trace element Cu were identified as risk factors for the development of NTD. At the same time, low plasma levels of trace elements Zn and Se were also found to be risk factors for NTD. However, no association between Hg and Co plasma levels and increased risk for the development of NTD was observed. This study, while being the most comprehensive case study to date investigating the relationship between heavy metals and trace element levels and increased risk of NTD, nonetheless highlights the need for further research in order to make definite statements regarding this relationship. 相似文献
950.
Ahmet Kara Mehmet Guven Mahmut Sinan Yilmaz Deniz Demir Çağlayan Adigul Merve Durgut 《Acta oto-laryngologica》2019,139(6):517-521
Background: To our knowledge, there is no study comparing Ponto Plus® (Oticon Medical AB, Askim, Sweden) and Baha® 5 (Cochlear Bone Anchored Solutions AG, Mölnlycke, Sweden) available in the literature.Aims/objectives: The primary aim was to compare the performance of the Baha 5 with the Ponto Plus device in terms of speech understanding in quiet and in noise. In addition, to determine statistically whether or not the difference between the abutment systems created any variation in terms of skin reaction.Materials and methods: Twenty bone-anchored hearing instrument users, ten in each group, were evaluated for speech understanding in quiet and several signal-to-noise ratios using the Turkish Matrix Test in a two-speaker setup. The Holger classifications were also reviewed to determine adverse skin reactions.Results: It was revealed that the hearing results of both devices were similar and, when the skin reactions were compared, there was no statistically significant difference between the two-implant systems.Conclusions and significance: Because of the similar results of the groups, it can be interpreted as the key different device features such as the size, weight, colour alternatives, and the ease of use of the devices might be important in terms of device preference. 相似文献