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11.
Nonhereditary p53 mutations in T-cell acute lymphoblastic leukemia are associated with the relapse phase 总被引:2,自引:0,他引:2
We have previously reported that greater than 60% of human leukemic T- cell lines possess mutations in the p53 tumor suppressor gene. To determine whether T-cell acute lymphoblastic leukemia (T-ALL) patient samples possess p53 mutations, we screened peripheral blood-and bone marrow-derived leukemia samples, taken at diagnosis and at relapse, for p53 mutations. Exons 4 through 9 and selected intron regions of the p53 gene were analyzed using polymerase chain reaction-single-strand conformation polymorphism and direct sequencing. p53 mutations were found in 0 of 15 T-ALL diagnosis samples, as compared with 10 of 36 (28%) T-ALL relapse samples. To determine whether p53 mutations play a role in the recurrence (relapse) of T-ALL, two special groups of T-ALL patients were studied: (1) a group of 8 relapse patients whose disease was refractory to chemotherapeutic treatment, and (2) a group of 6 "paired" T-ALL cell samples from patients for whom we possess both diagnosis and relapse samples. Three of 8 relapsed patients (37.5%) whose disease was refractory to the reinduction of remission by chemotherapy possessed missense mutations of the p53 gene. All 3 cases had mutations in exon 5. Among the paired samples, 3 of 6 patients harbored p53 mutations at disease recurrence, but possessed only wild- type p53 alleles at diagnosis. One case had mutation on exon 4, 1 case in exon 5, and 1 case in exon 8 with loss of heterozygosity. These data clearly indicate that recurrence of T-ALL is associated with missense mutations in p53. Our results indicate that (1) mutations of p53 do occur in T-ALL in vivo, and such mutations are associated with the relapse phase of the disease; and (2) p53 mutation is involved in the progression of T-ALL. This conclusion is supported by our observation that the introduction of T-ALL-derived mutant p53 expression constructs into T-ALL cell lines further increases their growth rate in culture, enhances cell cloning in methylcellulose, and increases tumor formation in nude mice. 相似文献
12.
碱离子水饮用后血小板聚集率的的变化(附30例报告) 总被引:1,自引:0,他引:1
目的:报告30例饮用豪斯牌碱离子水前、后血小板聚集率的变化。方法:饮用碱离子水前、后(2~3月,>3~6月)作比浊法血小板聚集试验,以1分钟、5分钟及5分钟内最大聚集率(Max%)为指标,同时检测部分血粘度指标及凝血因子,并用自动生化仪检测血糖、血脂、主要电解质及部分肝、肾功能。结果:饮碱离子水后,血小板聚集率明显下降,而以疾病组(Max>80%)下降尤为明显,P均<0.001。饮碱离子水后血小板聚集率的下降,部分可能与损伤的血管内皮得到修复有关。主要电解质及部分肝、肾功能无明显异常改变。结论:由于心、脑血管血栓性疾病患者血小板聚集率多明显升高,饮碱离子水后血小板聚集率明显下降,且长期饮用对主要电解质及部分肝、肾功能无明显异常改变,作者认为碱离子水使用方例、安全、有效、价廉,因而对心、脑血管血栓性疾病防治方面可能是一种积极的辅助方法,值得临床进一步探索。 相似文献
13.
T L?pp?nen AL Saukkonen W Serlo P Tapanainen A Ruokonen M Knip 《Archives of disease in childhood》1997,77(1):32-37
OBJECTIVE: Children with hydrocephalus are characterised by slow linear growth in prepuberty, accelerated physical maturation during puberty, and reduced final height. We aimed to study the possible roles of growth hormone, insulin-like growth factor-I (IGF-I), and IGF binding protein-3 (IGFBP-3) in this growth pattern. STUDY DESIGN: One hundred and fourteen patients with shunted hydrocephalus (62 males) aged 5 to 20 years, of whom 17 had spina bifida (six males), and 73 healthy controls (38 males) were studied. Anthropometric measures, body mass index, and body fat mass were assessed and the stage of puberty was determined. Serum growth hormone and plasma IGF-I and IGFBP-3 concentrations were measured. RESULTS: The patients comprised 44 (26 males) who were prepubertal and 70 (36 males) pubertal or postpubertal, while 32 of the controls (19 males) were prepubertal and 41 (19 males) pubertal or postpubertal. The prepubertal children with hydrocephalus had lower IGF-I (p = 0.002) and IGFBP-3 concentrations (p < 0.001) than the controls, and the pubertal children had four times lower basal growth hormone concentrations (p < 0.001). There was a correlation between height SD score and IGF-I levels in the total patient population (r = 0.23; p = 0.01). Peripheral IGF-I concentrations peaked at pubertal stages 2-3 in the female patients and at stage 4 in the controls. The prepubertal patients on antiepileptic treatment, carbamazepine in most cases (73%), had higher IGF-I (p = 0.01) and IGFBP-3 concentrations (p = 0.03) than those who had never been treated with antiepileptic drugs, but still lower IGFBP-3 levels than the controls (p = 0.01). CONCLUSION: Based on these findings, it can be concluded that reduced growth hormone secretion may contribute to the pattern of slow linear growth and reduced final height observed in these patients. 相似文献
14.
OBJECTIVE: Although breastfeeding is associated with lower rates of a variety of infant illnesses, skeptics have suggested that much of the association is attributable to confounding, even after appropriate statistical adjustment. This article utilizes a novel design to investigate changes in infant illness at the community level after a successful breastfeeding promotion program. METHODS: In this population-based cohort study, the medical records of all infants born in one Navajo community the year before a breastfeeding promotion program (n = 977) and the year during the intervention (n = 858) were reviewed. Outcomes assessed include changes after the intervention in: proportion breastfeeding and/or breastfeeding exclusively; incidence of common infant illnesses in the first year of life; and feeding-group specific incidence of illness. RESULTS: The proportion of women breastfeeding exclusively for any period of time increased from 16.4% to 54.6% after the intervention. The percent of children having pneumonia and gastroenteritis declined 32. 2% and 14.6%, respectively, after the intervention. Feeding-group specific rates of these illnesses were unchanged, indicating that the decline observed was attributable to the increased proportion of infants breastfeeding. In contrast, rates of croup and bronchiolitis increased after the intervention among those fed formula from birth, suggesting a viral epidemic which was limited to those never exclusively breastfed. Finally, sepsis declined in both formula-fed and breastfed infants after the intervention, suggesting that other factors affected this illness outcome after the intervention. CONCLUSIONS: Increasing the proportion of exclusively breastfed infants seems to be an effective means of reducing infant illness at the community level. The experimental design suggests that the increased incidence of illness among minimally breastfed infants is causally related to lack of breast milk, rather than being attributable to confounding. 相似文献
15.
16.
PCR-SSCP快速检测耐多药结核分枝杆菌 总被引:1,自引:0,他引:1
目的:了解本地区结核病耐药基因突变情况,探讨PCR-SSCP作为新的分子药敏试验方法在临床的应用价值。方法:通过提取耐INH、RFP、SM的肺结核患者痰中结核分枝杆菌DNA,进行PCR-SSCP分析,检测结核分枝杆菌rpoB、katG、rpsL基因是否存在突变,并与传统L-J药敏实验对照。结果:30株耐多药株中,耐RPF、INH、SM基因突变阳性率为90%(27/30)、63%(19/30)、53%(16/30)。3个基因联合突变共8株(26.7%),2个基因联合突变共18株(60%),即26株(86.7%)。单基因突变共2株,2株无基因突变。结论:通过PCR-SSCP方法可检测出绝大部分耐多药结核病的耐药基因,rpoB、katG、rpsL基因突变与本地区结核杆菌对RFP、INH、SM耐药性有关。与传统L-J药敏实验对比,PCR-SSCP是一种敏感、快速的指导临床用药的先进检测方法。 相似文献
17.
M.F. MANJI I. AL BADAWI† A. EL ENBABY & N. AL BAREEDY† 《International journal of gynecological cancer》2006,16(2):675-680
Female circumcision is a traditional practice common in African countries. It involves partial or total removal of external female genitalia. It has led to many complications, in particular, the scarring of the external genitalia. The consequence is a very narrow introitus making the intracavitary brachytherapy treatment component difficult when these women develop cancer of cervix. We present two such cases from our institution. Our aim is to make the radiation and gynecological oncologists, both in developed and developing countries, aware of this practice and the problems they can encounter in the management of such cases. Intracavitary brachytherapy is an important component in the potentially curative role of radiation therapy for cervical cancer. Every effort should be made to ensure that the sequelae of genital mutilation does not deprive these women of the same standard of care as the general population. 相似文献
18.
19.
Sustained release bioadhesive effervescent ketoconazole microcapsules tabletted for vaginal delivery
H. Y. Karasulu F. Taneri E. Sanal T. Güneri G. Ertan 《Journal of microencapsulation》2013,30(3):357-362
Microcapsules of ketoconazole with 1:1 and 1:2 core-wall ratios were prepared by means of the phase separation technique using sodium carboxymethylcellulose as a coating material. The microcapsules were mixed with effervescent granules and were tabletted. Dissolution studies of microcapsules, tabletted microcapsules and commercial ovules were carried out with a new basket method (horizontal rotating basket). A good sustained action was obtained with tablets. Micromeritic investigations were carried out on microcapsules in order to standardize the microcapsule product and to optimize the pilot production of the dosage forms prepared with these microcapsules. Bulk volume and weight, tapping volume and weight, fluidity, angle of repose, weight deviation, relative deviation, particle size distribution, density and porosity values of the microcapsules were determined. In addition, to evaluate whether some kind of glidant will be needed during tabletting of microcapsules, the Hausner ratio and consolidation index were also calculated and it may be concluded that microcapsules do not need any glidant. 相似文献
20.
MOHAMED AL KARAWI FA ABDELRAHMAN ELSHEIKH MOHAMED MBBS Dip.Ven. MRCP DTMH M. ANWAR HANID MD MRCP RAJI AL OTAIBI FA 《Journal of gastroenterology and hepatology》1986,1(2):151-157
Abstract Thirty consecutive patients with bleeding oesophageal varices secondary to schistosomal liver disease received injection sclerotherapy. These formed a part of a prospective study, to evaluate the role of sclerotherapy in the treatment of bleeding oesophageal varices due to different aetiological factors in patients seen at the Gastroenterology Unit, Riyadh Armed Forces Hospital, Saudi Arabia, between December 1980 and July 1984.
Schistosomiasis is endemic in parts of Saudi Arabia. Sclerotherapy has a special place in schistosomal liver disease as liver function is well preserved in this disease. The new antischistosomal drugs are effective and may halt the progress of the disease. However, in many patients portal hypertension with bleeding oesophageal varices is found at diagnosis. Of the patients with schistosomiasis, 63.3% were Group A Child's Classification. Oesophageal varices have been eradicated in 11 cases during the mean follow-up period of 28 months (range 3-44 months). Four patients were referred for surgery because of bleeding gastric varices, two of whom died following operation. One patient, who was also hepatitis B surface antigen positive, died due to re-bleeding from gastric varices. The remaining 25 patients had no recurrence of bleeding and their liver function remained satisfactory.
Surgical procedures for oesophageal varices in schistosomiasis carry the risk of peri-operative and postoperative morbidity and mortality. In contrast, complications following sclerotherapy are minor compared to surgical procedures and none of our patients had any serious sclerotherapy complications. 相似文献
Schistosomiasis is endemic in parts of Saudi Arabia. Sclerotherapy has a special place in schistosomal liver disease as liver function is well preserved in this disease. The new antischistosomal drugs are effective and may halt the progress of the disease. However, in many patients portal hypertension with bleeding oesophageal varices is found at diagnosis. Of the patients with schistosomiasis, 63.3% were Group A Child's Classification. Oesophageal varices have been eradicated in 11 cases during the mean follow-up period of 28 months (range 3-44 months). Four patients were referred for surgery because of bleeding gastric varices, two of whom died following operation. One patient, who was also hepatitis B surface antigen positive, died due to re-bleeding from gastric varices. The remaining 25 patients had no recurrence of bleeding and their liver function remained satisfactory.
Surgical procedures for oesophageal varices in schistosomiasis carry the risk of peri-operative and postoperative morbidity and mortality. In contrast, complications following sclerotherapy are minor compared to surgical procedures and none of our patients had any serious sclerotherapy complications. 相似文献