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Cell cycling in bladder carcinoma determined by monoclonal antibody Ki67   总被引:4,自引:0,他引:4  
Current methods of predicting prognosis in transitional cell carcinoma of the bladder fail to provide consistently reliable information about future tumour behaviour. The monoclonal antibody Ki67 recognises an antigen present in actively dividing cells and Ki67 reactivity has been shown to correlate with conventional prognostic indicators in several tumours. In this study, Ki67 antibody was used to determine the proportions of cells undergoing active division in 26 transitional cell carcinomas of the bladder. The proportion of cells stained in muscle invasive tumours (12.3 +/- 5.4%) was significantly greater than in superficial tumours (4.3 +/- 1.9%) and poorly differentiated tumours showed significantly greater proportions of cells staining compared with well or moderately well differentiated tumours. These results show that Ki67 reactivity correlates with high tumour stage and poor differentiation. Ki67 staining provides an easy method of determining tumour cell turnover that might provide additional prognostic information.  相似文献   
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Epidermal growth factor receptor and bladder cancer: a review.   总被引:2,自引:0,他引:2  
Recently, expectations have been raised that molecular biological studies of human tumours may be of value in helping to predict future clinical behaviour, in terms of therapeutic response and long-term survival. The epidermal growth factor receptor (EGFr) is a cell surface receptor for EGF and transforming growth factor-alpha which is overexpressed by a number of human tumours. This article principally reviews previous investigations of the role of the epidermal growth factor receptor in bladder cancer and examines methods of detection, the correlation between EGFr status and known prognostic indicators and the value of assessing EGFr status in predicting clinical outcome in patients with bladder cancer. Recent studies of the c-erbB-2 proto-oncogene in bladder cancer and of cell cycling using Ki-67 are included.  相似文献   
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The origin of image artifacts in an off-resonance spin-locking experiment is shown to be imperfections in the excitation flip angle. A pulse sequence for off-resonance spin locking is implemented that compensates for imperfections in the excitation flip angle through an off-resonance rotary echo. The off-resonance rotary echo alternates the frequency offset and phase of the RF transmitter during two spin-locking pulses of equal duration. The underlying theory is detailed, and MR images demonstrate the effectiveness of the technique in agarose gel phantoms and in in vivo human brain at 3T.  相似文献   
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The patient was diagnosed in childhood as having severe congenital neutropenia and had recurrent admissions with severe infections. In 1987, prior to getting married, she was sterilized. She continued to require i.v. antibiotics when she contracted a severe infection. On one occasion, she was treated with growth colony stimulating factor (G- CSF). Her increased neutrophil count was sustained following this treatment. In June 1993, she wished to start a family and underwent in- vitro fertilization (IVF) treatment. G-CSF was given prior to oocyte retrieval. She conceived on her first cycle and an ultrasound scan revealed a singleton pregnancy. Throughout the course of the pregnancy, her white cell count was monitored closely and remained at <1.0x10(9)/l. The pregnancy progressed uneventfully and at 37 weeks gestation she was admitted for G-CSF injections. At 38 weeks she was delivered of a boy weighing 3350 g, by elective Caesarean section. His white cell count was normal. This is the first case of G-CSF being used before conception and during pregnancy in a patient with congenital neutropenia. It shows that advances in cytokine therapy and close interdisciplinary liaison can lead to a successful outcome and help patients, who would otherwise remain childless, to achieve a family.   相似文献   
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The aim of the study was to determine whether a prior diagnostic testicle biopsy can predict success or failure of testicular sperm extraction (TESE) with intracytoplasmic sperm injection (ICSI) in patients with non-obstructive azoospermia caused by testicular failure, and what is the minimum threshold of sperm production in the testis which must be surpassed for spermatozoa to reach the ejaculate. Forty- five patients with non-obstructive azoospermia caused by testicular failure underwent diagnostic testicle biopsy prior to a planned future TESE-ICSI procedure. The diagnostic testicle biopsy was analysed quantitatively, and correlated with the quantitative findings of spermatogenesis in patients with normal spermatogenesis, as well as with the results of subsequent attempts at TESE-ICSI. Men with non- obstructive azoospermia caused by germinal failure had a mean of 0-6 mature spermatids/seminiferous tubule seen on a diagnostic testicle biopsy, compared to 17-35 mature spermatids/tubule in men with normal spermatogenesis and obstructive azoospermia. These findings were the same for all types of testicular failure whether Sertoli cell only, maturation arrest, cryptorchidism, or post-chemotherapy azoospermia. Twenty-two of 26 men with mature spermatids found in the prior testis biopsy had successful retrieval of spermatozoa for ICSI, 12 of their partners became pregnant, and are either ongoing or delivered. The study suggests that 4-6 mature spermatids/tubule must be present in the testis biopsy for any spermatozoa to reach the ejaculate. More than half of azoospermic patients with germinal failure have minute foci of spermatogenesis which are insufficient to produce spermatozoa in the ejaculate. Prior diagnostic testicle biopsy analysed quantitatively (for the presence of mature spermatids) can predict subsequent success or failure with TESE-ICSI. Incomplete testicular failure may involve a sparse multi-focal distribution of spermatogenesis throughout the entire testicle, rather than a regional distribution. Therefore, it is possible that massive testicular sampling from many different regions of the testes may not be necessary for successful TESE-ICSI.   相似文献   
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β-Lactoglobulin was isolated from infant formulae that were ultra high temperature (UHT) -treated, sterilized or spray-dried. The effect of the isolated β-lactoglobulin on SfaII-fimbriae-mediated adhesion of Escherichia coli to human ileostomy glycoproteins was studied in vitro. β-Lactoglobulin isolated from sterilized formulae was found to perform significantly less well than preparations from spray-dried formulae (p = 0:05). Great heterogeneity was observed in the adhesion inhibitory capacity of β-lactoglobulin isolated from UHT-treated formulae. Therefore, no significant difference was observed between UHT-treated and sterilized formulae or spray-dried formulae (p < 0:10). It can be hypothesized that β-lactoglobulin from spray-dried and some UHT-treated infant formulae may affect the colonization of mucous membranes by E. coli strains causing neonatal septicaemia and meningitis.  相似文献   
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