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11.
Chickens have two major regions encoding major histocompatibility complex (MHC) class Iα genes and MHC class IIß genes, the serological and functional B‐system and the Rfp‐Y‐system. Recently, they have been shown to assort in a genetically independent way although still located on the same microchromosome. Moreover, the monomorphic MHC class IIα gene maps at a third locus located 5 c m from the nearest class IIß genes, located in the B‐system ( Kaufman et al., 1995 ). A pedigree family was studied in three generations in order to assign MHC class IIß restriction fragments observed in Southern blot analyses to either the B‐system, the Rfp‐Y‐system or the B‐Lα locus. In this study, we demonstrate by classical genetic testing of chickens within this fully pedigreed family the existence of an MHC class II‐like polymorphic restriction fragment that segregates independently of the B‐system, the Rfp‐Y‐system and of the B‐Lα locus.  相似文献   
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The recognized urologic tumor spectrum in hereditary non-polyposis colon cancer includes ureteral and renal pelvis malignancies. Here, we report a family in which the proband, who had three metachronous adenocarcinomas of the colon and rectum (at ages 54, 57, and 60), presented with an adenocarcinoma of the prostate at age 61. Immunohistochemical (IHC) staining of colonic, rectal, and prostatic tumor tissues demonstrated lack of expression of both MSH2 and MSH6. Accordingly, microsatellite instability (MSI) was found in the rectal, colonic, and prostatic tumors. The kindred complies with the Amsterdam criteria for HNPCC, as five members over three generations had colorectal cancer. Molecular investigations were initiated when the proband's son presented with an adenocarcinoma of the colon at age 35. Southern blotting analysis of genomic DNA led to identification of a novel genomic deletion encompassing exon 5 of the MSH2 gene. Although prostate cancer has occasionally been described in HNPCC families, to the best of our knowledge, this is the first report where the MSI and IHC analysis of the prostatic adenomcarcinoma clearly link its aetiology to the germline mismatch repair mutation. Hence, prostate cancer should be included in the HNPCC tumor spectrum.  相似文献   
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Genomic deletions of the MSH2 gene are a frequent cause of hereditary nonpolyposis colorectal cancer (HNPCC), a common hereditary predisposition to the development of tumors in several organs including the gastrointestinal and urinary tracts and endometrium. The mutation spectrum at the MSH2 gene is extremely heterogeneous because it includes nonsense and missense point mutations, small insertions and deletions leading to frameshifts, and larger genomic deletions, the latter representing approximately 25% of the total mutation burden. Here, we report the identification and molecular characterization of the first paracentric inversion of the MSH2 locus known to cause HNPCC. Southern blot analysis and inverse PCR showed that the centromeric and telomeric breakpoints of the paracentric inversion map within intron 7 and to a contig 10 Mb 3' of MSH2, respectively. Pathogenicity of the paracentric inversion was demonstrated by conversion analysis. The patient's lymphocytes were employed to generate somatic cell hybrids to analyze the expression of the inverted MSH2 allele in an Msh2-deficient rodent cellular background. The inversion was shown to abolish MSH2 expression by both northern and western analysis. This study confirms that Southern blot analysis still represents a useful and informative tool to screen for and identify complex genomic rearrangements in HNPCC. Moreover, monoallelic expression analysis represents an attractive approach to demonstrate pathogenicity of unusual mutations in autosomal dominant hereditary conditions.  相似文献   
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A blind study comparing abdominal ultrasound and cystoscopy was carried out in 186 patients. 20 bladder tumours sized from 2 to 5 mm were overlooked. Combination with urine cytology increased the diagnostic sensitivity. In order to reduce costs and patient inconvenience in the bladder tumour control population abdominal ultrasound and urine cytology is advocated as an alternative to cystoscopy. This control modality seems safe in patients with "low-risk" bladder tumour disease.  相似文献   
16.
Diagnosis and treatment of bronchial rupture from blunt thoracic trauma   总被引:4,自引:0,他引:4  
目的 探讨外伤性支气管断裂的诊断与治疗。方法 回顾性分析 196 9年 6月— 1999年 6月我院收治的 31例外伤性支气管断裂的患者 ,全部行胸部X线摄片、支气管断层、支气管镜检查。并对其外科治疗和并发症进行探讨。结果 通过支气管断层、支气管镜检查全部得到明确诊断。 2 6例施行端端吻合术 ,4例施行全肺切除术 ,1例用带血管蒂的肋间肌、肋骨瓣修补破裂成功。 1例术后死于呼吸困难综合症 ,其余 30例效果满意。本给 81% (2 5 31)为延迟诊断与治疗。典型临床表现有 :皮下气肿、呼吸困难、伤后昏迷间期。X线表现 :纵隔气肿、气胸、萎陷肺下垂症、肺的阴影增宽。结论 支气管镜是最实用、最准确的诊断与治疗方法。术中使用支气管镜可较容易地找到支气管破裂处。术后肺功能恢复良好  相似文献   
17.
BACKGROUND: Several studies have suggested that better results are obtained after laparoscopic repair of inguinal hernia than after conventional operation. This is most obvious for bilateral and recurrent hernias but less accepted for primary unilateral hernias. METHODS: This was a randomized clinical trial comparing transabdominal preperitoneal laparoscopic repair with the Shouldice technique in patients with primary unilateral hernia. Some 138 patients were randomized to laparoscopic hernia repair and 130 to open surgical repair. RESULTS: The complication rates in the two groups were similar. In the laparoscopic group the patients returned to work more rapidly with a median time of 13 versus 18 days (P < 0.005) and had a shorter period of analgesia intake with a median time of 2.1 versus 2.7 days (P < 0.02). The follow-up was 97.8 per cent complete. At a median of 12 months, four recurrences (2.9 per cent) were detected in the laparoscopic group and three (2.3 per cent) in the open group. CONCLUSION: This study shows that in patients with a primary unilateral hernia laparoscopic repair results in less postoperative pain and a quicker recovery than open repair.  相似文献   
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Upshaw–Schulman syndrome (USS) is due to severe congenital deficiency of von Willebrand factor (VWF)‐cleaving protease ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 domains, nr 13) activity resulting in the presence of unusually large forms of VWF in the circulation, causing intravascular platelet clumping and thrombotic microangiopathy. Our patient, a 26‐year‐old man, had attacks of thrombotic thrombocytopenic purpura (TTP) with thrombocytopenia and a urine dipstick positive for hemoglobin (4+), often as the only sign of hemolytic activity. He had ADAMTS13 activity of <1% of normal plasma without the presence of inhibitors of ADAMTS13. ADAMTS13 deficiency was caused by two new mutations of the ADAMTS13 gene: a deletion of a single nucleotide in exon17 (c. 2042 delA) leading to a frameshift (K681C fs X16), and a missense mutation in exon 25 (c.3368G>A) leading to p.R1123H. This case report confirms the importance of the analysis of the ADAMTS13 activity and its inhibitor in patients who have episodes of TTP, with a very low platelet count and sometimes without the classic biochemical signs of hemolysis.  相似文献   
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