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Arteriovenous malformation of the uterus is a rare uterine abnormality. This entity is generally associated with the presence of molar disease, choriocarcinoma and uterine surgery, but may be congenitally acquired. The presence of an arteriovenous malformation generally leads to unexplained profuse uterine bleeding. The diagnosis of this entity has traditionally been made by arteriography, and the treatment is usually hysterectomy. We present a patient with an arteriovenous malformation of the uterus whose prior delivery was by Cesarean section. The patient experienced episodes of heavy vaginal bleeding in the first month following the procedure of suction curettage for a first-trimester pregnancy loss. Chorionic villus sampling performed prior to the procedure showed a chromosomally normal fetus. The diagnosis of an arteriovenous malformation was made by color Doppler velocimetry and confirmed with arteriography. The patient desired to maintain her fertility. Interventional radiological techniques were successfully utilized to obliterate the arteriovenous malformation with the use of polyvinyl alcohol particles (250 micro m) and gelfoam. Discussion includes the presenting signs and symptoms along with the method of both diagnosis and conservative management.  相似文献   
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We studied the usefulness of the determination of plasma D-dimer levels (using an ELISA) in combination with non-invasive testing with impedance plethysmography (IPG) or real-time ultrasonography (US) for the diagnosis of deep-vein thrombosis (DVT), in outpatients with clinically suspected DVT. This combined approach was compared to serial non-invasive testing alone in these patients. The sensitivity of a positive D-dimer test (greater than 300 micrograms/l) for the presence of DVT was 100% (70/70 patients; 95% C.I.: 95-100%), whereas the specificity was 29% (69/239 patients; 95% C.I.: 23-34%). The proportion of patients in which a definitive decision about the presence or absence of DVT could be made on the day of referral, was calculated for both approaches. When applying the combined approach, in 42% of all referred patients the diagnosis of DVT could either be established or refuted on entry, as opposed to only 19% of patients using serial non-invasive testing alone. Also, the costs per DVT diagnosed were calculated for the two diagnostic approaches. For the diagnosis of DVT the costs using serial IPG were comparable to the costs using the combination of IPG and the D-dimer test. The same conclusion holds for the comparison of serial US with the combination of US and D-dimer testing. We conclude that for the diagnosis of DVT in symptomatic outpatients the combination of non-invasive testing with the D-dimer test might be preferred over serial non-invasive testing alone, although the safety of such an approach remains to be established in future management studies.  相似文献   
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Silver binding nucleolar regions (AgNORs) were evaluated in normal endocervix, adenocarcinoma, and its potential precursor, adenocarcinoma in situ (AIS), in an attempt to increase an understanding of the natural history of cervical adenocarcinoma and to identify a marker for abnormal endocervical (atypical glandular) cells which could aid diagnosis and follow up of endocervical lesions. For every 50 cells the mean AgNOR counts were as follows: normal endocervical cells (n = 15) 79.8 (95% Cl 68-91); AIS (n = 20) 200.7 (95% Cl 182-219); and invasive adenocarcinoma (n = 30) 299 (271-328). There was no overlap between the groups of normal endocervical cells and invasive adenocarcinoma, but there was significant overlap between cases of invasive adenocarcinoma and carcinoma in situ. In six out of 17 cases with AIS, NOR count in adjacent morphologically normal glandular cells ("internal" controls) was increased when compared with the "external" (normal endocervical) control group. This suggests the presence of wider field changes not previously identified using routine histological methods. The findings suggest that AIS is a potential premalignant precursor of invasive adenocarcinoma, but that assessment of NORs is of no practical use in discriminating between the histological types of cervical carcinoma.  相似文献   
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Competitive control of the self-renewing T cell repertoire   总被引:1,自引:0,他引:1  
We develop a mathematical model for the self-renewing part of the T cell repertoire. Assuming that self-renewing T cells have to be stimulated by immunogenic MHC-peptide complexes presented on the surfaces of antigen-presenting cells, we derive a model of T cell growth in which competition for MHC-peptide complexes limits T cell clone sizes and regulates the total number of self-renewing T cells in the animal. We show that for a sufficient diversity and/or degree of cross-reactivity, the total T cell number hardly depends upon the diversity of the T cell repertoire or the diversity of the set of presented peptides. Conversely, for repertoires of lower diversity and/or cross-reactivity, steady-state total T cell numbers may be limited by the diversity of the T cells. This provides a possible explanation for the limited repertoire expansion in some, but not all, mouse T cell re-constitution experiments. We suggest that the competitive interactions described by our model underlie the normal T cells numbers observed in transgenic mice, germ-free mice and various knockout mice.   相似文献   
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Localization of a gene for otosclerosis to chromosome 15q25-q26   总被引:5,自引:0,他引:5  
Among white adults otosclerosis is the single most common cause of hearing impairment. Although the genetics of this disease are controversial, the majority of studies indicate autosomal dominant inheritance with reduced penetrance. We studied a large multi- generational family in which otosclerosis has been inherited in an autosomal dominant pattern. Five of16 affected persons have surgically confirmed otosclerosis; the remaining nine have a conductive hearing loss but have not undergone corrective surgery. To locate the disease- causing gene we completed genetic linkage analysis using short tandem repeat polymorphisms (STRPs) distributed over the entire genome. Multipoint linkage analysis showed that only one genomic region, on chromosome 15q, generated a lod score >2.0. Additional STRPs were typed in this area, resulting in a lod score of 3.4. STRPs FES (centromeric) and D15S657 (telomeric) flank the 14. 5 cM region that contains an otosclerosis gene.   相似文献   
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