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531.
BackgroundCholangiocarcinoma is a very aggressive tumor with poor survival. Therefore, early diagnosis and surgical resection are of paramount importance. Its diagnosis is difficult because access to the tumor is not easy. Biopsy is possible only for intrahepatic cholangiocarcinoma, which accounts for 10% of cases. Routine brush cytology from endoscopic retrograde cholangiopancreatography (ERCP) has a high specificity of 100% but unfortunately a low sensitivity of 30%. In this review we briefly describe new diagnostic techniques applicable to ERCP brush cytology specimens and targeting the genetic background of the disease, in particular fluorescence in situ hybridization (FISH) and digital image analysis (DIA).Date SourcesThe PubMed database up to 2011 was used for the retrieval of relevant articles. The search terms FISH, fluorescence in situ hybridization, DIA, digital image analysis and cholangiocarcinoma were used. Both original and review articles were used.ResultsFISH identifies cells with chromosomal abnormalities, mainly numerical aberrations, using a mixture of fluorescence-labeled probes. FISH offers a higher sensitivity than routine cytology, retaining a high level of specificity. The DIA criterion for malignancy is demonstration of aneuploidy. This technique increases the sensitivity to 40%, but the specificity remains low. Preliminary data from application to other tumors suggest that combination of FISH and DIA may be of further benefit.ConclusionsThe new techniques offer a significantly enhanced diagnostic efficacy in the evaluation of ERCP brush specimens. Apart from contributing to a more timely diagnosis, their wider application to cholangiocarcinoma may also facilitate the genetic study of the disease and add to our understanding of oncogenesis at the molecular level, with the prospect of identifying targets for novel therapeutic interventions.  相似文献   
532.
Simmonds  MA; Sobczak  G; Hauptman  SP 《Blood》1982,59(3):555-562
Human peripheral blood lymphocytes can be phenotypically identified by the presence of one or both of two proteins, 225,000-dalton macromolecular insoluble cold globulin (225-MICG) and 185,000-dalton MICG (185-MICG). T cells synthesize and insert into their plasma membrane 225-MICG, null cells 185-MICG, and B cells both 225 and 185- MICG. In contrast, the monoclonal B cells of chronic lymphocytic leukemia are characterized by the presence of 225-MICG and the absence of 185-MICG. We have recently found it possible to chemically deplete 185-MICG from viable normal B cells by treating them with diisopropylfluorophosphate (DFP), thus making normal B cells phenotypically resemble leukemic cells. In the present report we determined whether certain peculiar properties of these leukemic cells would be associated with the normal B cells chemically depleted of 185- MICG. In normal B cells, SIg diffuses in the lipid bilayer to form clusters and caps under appropriate conditions, while in chronic lymphocytic leukemia (CLL) cells this does not occur. Normal B cells depleted of 185-MICG fail to undergo capping of SIg or surface MICG under appropriate conditions. Both DFP-treated B cells and CLL cells tend to rupture when smeared on a glass slide. Both CLL cells and DFP- treated B cells fail to secrete 225-MICG after it has been synthesized intracellularly. The relationship of these findings to the mechanisms of secretion and capping are discussed.  相似文献   
533.
李兰敏  徐世平 《药学学报》1995,30(7):556-560
Since compounds Ⅲ and Ⅳ possess retinoid-like action and analogues of Ⅰ inhibit some cancer cells ,seventeen derivatives of chlorophenoxy acetamide were synthesized.Of the seven compounds screened ,two exhibit cytostatic activity(1 and 2).Mass spectra showeda special expulsion of SO2 and CO from the sulfonamide compounds,Nuclear magnetic resonancesplitting patterns of these compounds also showed interesting features.  相似文献   
534.
CASE REPORT: A 43-year-old man was hospitalized because of severe anemia and recurrent bouts of abdominal pain over 20 days. There was no known occupational exposure to toxins. Concomitantly, the patient's father complained of having the same symptoms. Familial lead poisoning was diagnosed when all 6 family members tested had high blood leads (31-64 micrograms/dL). RESULTS: Following detailed examination of the potential sources common to all members of the household, the cause of poisoning was determined to be corn flour containing 38.7 mg/g lead. Physicians are reminded to consider lead poisoning in the differential diagnosis of individuals with unexplained symptoms, particularly those of abdominal discomfort and anemia.  相似文献   
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