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A 63-year-old man with iron loss anaemia and hypercalcaemia was found to have a renal cell carcinoma. Despite the iron-deficient blood and bone marrow picture, the serum ferritin concentration was markedly raised. This was mainly due to a “basic isoferritin”. The serum parathormone concentration was normal. The serum ferritin and calcium concentrations returned to normal after the tumour was removed. We propose that the renal cell carcinoma cells in this patient secreted the basic isoferritin as well as humoral factor(s) responsible for hypercalcaemia.  相似文献   
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Gene conversion is a likely cause of mutation in PKD1   总被引:3,自引:0,他引:3  
Approximately 70% of the gene responsible for the most common form of autosomal dominant polycystic kidney disease ( PKD1 ) is replicated in several highly homologous copies located more proximally on chromosome 16. We recently have described a novel technique for mutation detection in the duplicated region of PKD1 that circumvents the difficulties posed by these homologs. We have used this method to identify two patients with a nearly identical cluster of base pair substitutions in exon 23. Since pseudogenes are known to be reservoirs for mutation via gene conversion events for a number of other diseases, we decided to test whether these sequence differences in PKD1 could have arisen as a result of this mechanism. Using changes in restriction digest patterns, we were able to show that these sequence substitutions are also present in N23HA, a rodent-human somatic cell hybrid that contains only the PKD1 homologs. Moreover, these changes were also detected in total DNA from several affected and unaffected individuals that did not harbor this mutation in their PKD1 gene copy. This is the first example of gene conversion in PKD1 , and our findings highlight the importance of using gene-specific reagents in defining PKD1 mutations.   相似文献   
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Predominance of null mutations in ataxia-telangiectasia   总被引:15,自引:4,他引:15  
Ataxia-telangiectasia (A-T) is an autosomal recessive disorder involving cerebellar degeneration, immunodeficiency, chromosomal instability, radiosensitivity and cancer predisposition. The responsible gene, ATM, was recently identified by positional cloning and found to encode a putative 350 kDa protein with a Pl 3-kinase-like domain, presumably involved in mediating cell cycle arrest in response to radiation-induced DNA damage. The nature and location of A-T mutations should provide insight into the function of the ATM protein and the molecular basis of this pleiotropic disease. Of 44 A-T mutations identified by us to date, 39 (89%) are expected to inactivate the ATM protein by truncating it, by abolishing correct initiation or termination of translation, or by deleting large segments. Additional mutations are four smaller in-frame deletions and insertions, and one substitution of a highly conserved amino acid at the Pl 3-kinase domain. The emerging profile of mutations causing A-T is thus dominated by those expected to completely inactivate the ATM protein. ATM mutations with milder effects may result in phenotypes related, but not identical, to A-T.   相似文献   
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We have used an avidin-biotin immunoperoxidase technique to localise epithelial cadherin (E-cadherin), a calcium-dependent cell-cell adhesion molecule, in 107 paraffin-embedded sections from 93 patients consisting of 24 with colorectal adenoma, 55 with rectal carcinoma and 14 with liver metastases. The corresponding primary colorectal tumours were also studied in these cases. E-cadherin was expressed by normal colorectal epithelial cells with typical membranous staining at the intercellular junctions. Loss of normal membranous E-cadherin expression and presence of cytoplasmic staining were found frequently in adenomas larger than 1 cm (P<0.01), with high grade dysplasia and villous histology (P<0.01). In primary rectal cancers, loss of membranous expression correlated with high tumour grade. No correlation was seen with Dukes and Jass stage, local extramural spread and 5-year recurrence rate. Complete loss of membranous E-cadherin immunoreactivity was seen in 7/14 (50%) liver metastases in which 6/7 (86%) showed intense membranous E-cadherin immunoreactivity in the corresponding primary tumour. Our data indicate that changes in E-cadherin immunoreactivity and cellular localisation correlate with size, severe dysplasia in adenomas and tumour grade in carcinomas. However, there seems to be no correlation between loss of membranous E-cadherin immunoreactivity and the invasive and metastatic potential of the carcinomas.  相似文献   
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Wire-guided localization (WGL) is the standard of care in the surgical treatment of nonpalpable breast tumors. In this study, we compare the use of a new magnetic marker localization (MaMaLoc) technique to WGL in the treatment of early-stage breast cancer patients. Open-label, single-center, randomized controlled trial comparing MaMaLoc (intervention) to WGL (control) in women with early-stage breast cancer. Primary outcome was surgical usability measured using the System Usability Scale (SUS, 0–100 score). Secondary outcomes were patient reported, clinical, and pathological outcomes such as retrieval rate, operative time, resected specimen weight, margin status, and reoperation rate. Thirty-two patients were analyzed in the MaMaLoc group and 35 in the WGL group. Patient and tumor characteristics were comparable between groups. No in situ complications occurred. Retrieval rate was 100% in both groups. Surgical usability was higher for MaMaLoc: 70.2 ± 8.9 vs. 58.1 ± 9.1, < 0.001. Patients reported higher overall satisfaction with MaMaLoc (median score 5/5) versus WGL (score 4/5), < 0.001. The use of magnetic marker localization (MaMaLoc) for early-stage breast cancer is effective and has higher surgical usability than standard WGL.  相似文献   
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AIMS: Sentinel lymph node biopsy has replaced the axillary lymph node dissection (ALND) in primary surgery for breast cancer in many hospitals and is expected to become the standard of care in due time. Since the sentinel lymph node is subjected to more extensive pathologic examination than the lymph nodes in the axillary dissection specimen, more patients are found to be node positive (N+); however many of them contain micro-metastases (相似文献   
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AIM: To provide a simple method for assessing centile change based on the British 1990 growth reference. STATISTICAL METHOD: The change in SD score over a period of time has SD square root of 2(1-r), where r is the correlation between the first and second SD score. This leads to an SD score for centile change. DATA: Annual height measurements from 2 to 9 years for 318 children from the French longitudinal growth study. RESULTS: The correlations between heights at different ages are higher for shorter measurement intervals and at older ages. The chance of a child's height centile falling one centile band width is correspondingly smaller for shorter measurement intervals and at older ages. An increase in height measurement error reduces the correlations and dramatically increases the chances of centile crossing. CONCLUSIONS: Quantitative height monitoring based on centile change is provided for whole year periods between 2 and 9 years of age. Effective monitoring requires the measurement error to be as small as possible.  相似文献   
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