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11.
How to use Chlamydia antibody testing in subfertility patients   总被引:1,自引:9,他引:1  
Screening for tubal factor subfertility by means of Chlamydia antibody testing (CAT) was introduced into the initial work-up of subfertile couples several years ago. The results reported, however, are heterogeneous, and no uniformity exists in cut-off levels of titres, or in definitions of tubal factor subfertility. We performed a prospective cohort study to evaluate the implications of varying the definitions of tubal pathology and of modifying the cut-off levels on the clinical impact of CAT in predicting tubal factor subfertility. In 227 consecutive patients who attended our fertility clinic, the Chlamydia IgG antibody titre was determined and related to tuboperitoneal abnormalities at laparoscopy as a reference standard. According to received operating characteristic (ROC) curve analysis, a titre of 16 is the optimum cut-off level. Increasing the cut-off level improves specificity and positive likelihood ratio (LR+), at the expense of sensitivity and negative LR (LR-). Changing the definition of tubal factor subfertility from unspecified tuboperitoneal abnormalities into extensive adhesions and/or bilateral distal tubal occlusion improves LR+, LR- and kappa significantly. We conclude that CAT is more accurate in predicting severe distal tubal pathology than unspecified tuboperitoneal abnormalities. Although from a statistical point of view a titre of 16 is the optimum cut-off level, from a clinical point of view 32 or 64 may be preferable, depending on the aim of screening and the inception cohort.   相似文献   
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Impaired expression of the FMR1 gene is responsible for the fragile X mental retardation syndrome. The FMR1 gene encodes a cytoplasmic protein with RNA-binding properties. Its complex alternative splicing leads to several isoforms, whose abundance and specific functions in the cell are not known. We have cloned in expression vectors, cDNAs corresponding to several isoforms. Western blot comparison of the pattern of endogenous FMR1 proteins with these transfected isoforms allowed the tentative identification of the major endogenous isoform as ISO 7 and of a minor band as an isoform lacking exon 14 sequences (ISO 6 or ISO 12), while some other isoforms (ISO 4, ISO 5) were not expressed at detectable levels. Surprisingly, in immunofluorescence studies, the transfected splice variants that exclude exon 14 sequences (and have alternate C-terminal regions) were shown to be nuclear. Such differential localisation was however not seen in subcellular fractionation studies. Analysis of various deletion mutants suggests the presence of a cytoplasmic retention domain encoded in exon 14 and of a nuclear association domain encoded within the first eight exons that appear however to lack a typical nuclear localisation signal.   相似文献   
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目的探讨宫颈液基细胞学及阴道镜检查在北京市社区妇女宫颈病变筛查中的临床意义。方法2006年6月至2007年6月对北京市展览路社区的795位20~54岁有性生活的妇女进行筛查。筛查对象接受妇科检查时,留取宫颈超柏氏薄层液基细胞学检测标本,并对宫颈细胞学异常者行阴道镜检查及活组织检查。结果宫颈细胞学阳性[≥ASC-US(不能明确意义的不典型鳞状细胞)]45例,占5.7%(45/795)。其中ASC-US33例,占73.3%(33/45);低度鳞状上皮内病变8例;高度鳞状上皮内病变3例;不典型腺细胞1例。细胞学阴性750例,占94.3%(750/795)。宫颈细胞学阳性的45例中,5例拒绝行阴道镜检查,占11.1%(5/45)。在行阴道镜活组织病理检查的40例中,慢性宫颈炎11例(27.5%);宫颈湿疣14例(35.0%);宫颈上皮内瘤样病变(CIN)1为7例(17.5%);CIN2为3例(7.5%);CIN3为4例(10.0%);早期浸润癌1例(2.5%)。细胞学阴性的750例中,宫颈湿疣2例(0.3%);CIN1为5例(0.7%);宫颈低级别腺上皮内病变1例(0.1%)。宫颈液基细胞学筛查CIN1及以上宫颈病变和宫颈癌的敏感度71.4%,特异度94.2%,阳性预测值37.5%,阴性预测值99.2%;筛查CIN2及以上宫颈病变和宫颈癌的敏感度100.0%,特异度96.0%,阳性预测值20.5%,阴性预测值100.0%。结论应重视并及时进行北京市社区人群宫颈病变的早期筛查,薄层液基细胞学结合阴道镜活组织检查及病理学检查,对提高早期宫颈癌筛查的准确性效果明显。  相似文献   
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Computed tomographic detection of nonbeta pancreatic islet cell tumors   总被引:6,自引:0,他引:6  
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A cell line, designated RS4;11, was established from the bone marrow of a patient in relapse with an acute leukemia that was characterized by the t(4;11) chromosomal abnormality. The cell line and the patient's fresh leukemic cells both had the t(4;11)(q21;q23) and an isochromosome for the long arm of No. 7. Morphologically, all cells were lymphoid in appearance. Ultrastructurally and cytochemically, approximately 30% of the cells possessed myeloid features. The cells were strongly positive for terminal deoxynucleotidyl transferase. They were HLA-DR positive and expressed surface antigens characteristic for B lineage cells, including those detected by anti-B4, BA-1, BA-2, and PI153/3. Immunoglobulin gene analysis revealed rearrangements of the heavy chain and kappa chain genes. The cells lacked the common acute lymphoblastic leukemia antigen and antigenic markers characteristic of T lineage cells. The cells reacted with the myeloid antibody 1G10 but not with other myeloid monoclonal antibodies. Treatment with 12-O-tetradecanoyl- phorbol-13-acetate induced a monocyte-like phenotype demonstrated by cytochemical, functional, immunologic, and electron microscopic studies. The expression of markers of both early lymphoid and early myeloid cells represents an unusual phenotype and suggests that RS4;11 represents a cell with dual lineage capabilities. To our knowledge, RS4;11 is the first cell line established from t(4;11)-associated acute leukemia.  相似文献   
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Conditioned medium (CM) obtained from a human hepatoma cell line, SK- HEP-1, contains colony-stimulating factors (CSFs) active on murine and human bone marrow-derived granulocyte and macrophage colony-forming units (CFU-GM) and a factor capable of inducing granulocyte-macrophage differentiation (GM-DF) of murine myelomonocytic leukemic cells WEHI- 3B(D+) and human promyelocytic leukemic cells HL-60 when assayed in semisolid agar cultures. The human active granulocyte-macrophage colony- stimulating factor (GM-CSF) for day 7 CFU-GM and the GM-DF for WEHI- 3B(D+) and for HL-60 are not separable by acrylamide agarose column chromatography, eluting at an apparent molecular weight between 20,000 and 35,000 daltons, or by isoelectric focusing (isoelectric point, pH 5.4). In addition, SK-HEP-1 CM contains erythroid burst-promoting activity (BPA) and a factor that promotes the growth of human mixed colonies. SK-HEP-1 cells, which grow as an adherent monolayer, appear not to be endothelial or monocytic in origin since by immunofluorescent staining they are negative for Ia (HLA-DR), monocyte antigen 1 and 2, lysozyme, and factor VIII-related antigen. Positive immunofluorescent staining for keratin and fibronectin suggests the possibility that SK- HEP-1 is an epithelial cell line. Constitutive production of GM-DF as well as other hematopoietic activities including GM-CSF, erythroid BPA, and an activity that promotes the growth of human mixed colony progenitors by a human epithelial tumor cell line, SK-HEP-1, suggests that this cell line is a valuable resource for both large-scale production of these factors and the cloning of the gene(s) that code for these regulators.  相似文献   
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To study the effect of chemotherapy on normal fat, skeletal muscle, and bone marrow, T1 and T2 relaxation times were measured in 15 patients with bone sarcoma before and after each cycle of preoperative chemotherapy. A section plane containing the tumor and if possible the nonaffected extremity was imaged with combined multiecho spin echo and inversion recovery pulse sequences. T1 and T2 relaxation times were calculated in the normal-appearing tissues. Although some variation was found in the values in the individual patient and between patients, no systematic changes of relaxation times of fat, muscle, or bone marrow occurred in the course of treatment. We conclude that the chemotherapy used in bone sarcoma has no effect on relaxation times of normal fat, muscle, and bone marrow, and that therefore these tissues may serve as a reference for the signal intensity of tumor.  相似文献   
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