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991.
992.
Five patients with subglottic stenosis, occurring either asa presenting symptom or as a manifestation in the course ofa systemic disease, are described. Indirect immunofluorescencerevealed the presence of circulating autoantibodies againstboth cytoplasmic and perinuclear constituents of neutrophilsin all five. Antibodies directed against a 29 kDa antigen ofthe azurophilic granules (two patients), against myeloperoxidase(one patient), and against both the 29 kDa antigen and myeloperoxidase(one patient) were found by enzyme-linked immunosorbent assay.These autoantibodies have previously been found in patientswith Wegener's granulomatosis, microscopic polyarteritis, (idiopathic)glomerulonephritis and Churg-Strauss syndrome. However, onlyone of these five patients fulfilled the criteria for theseconditions. Since these autoantibodies are seldom observed inother conditions, and other diseases had been excluded by carefulevaluation, we suggest that their presence places subglotticstenosis within the spectrum of necrotizing (granulomatous)vasculitis. Whether immunosuppressive therapy is always warrantedin patients with subglottic stenosis and circulating anti-neutrophilcytoplasmic antibodies is a matter of debate.  相似文献   
993.
Cervical spine hyperextension injuries: MR findings   总被引:8,自引:0,他引:8  
  相似文献   
994.
Gene transfer vectors based on adeno-associated virus (AAV) appear promising because of their high transduction frequencies regardless of cell cycle status and ability to integrate into chromosomal DNA. We tested AAV-mediated gene transfer into a panel of human bone marrow or umbilical cord-derived CD34+ hematopoietic progenitor cells, using vectors encoding several transgenes under the control of viral and cellular promoters. Gene transfer was evaluated by (1) chromosomal integration of vector sequences and (2) analysis of transgene expression. Southern hybridization and fluorescence in situ hybridization analysis of transduced CD34 genomic DNA showed the presence of integrated vector sequences in chromosomal DNA in a portion of transduced cells and showed that integrated vector sequences were replicated along with cellular DNA during mitosis. Transgene expression in transduced CD34 cells in suspension cultures and in myeloid colonies differentiating in vitro from transduced CD34 cells approximated that predicted by the multiplicity of transduction. This was true in CD34 cells from different donors, regardless of the transgene or selective pressure. Comparisons of CD34 cell transduction either before or after cytokine stimulation showed similar gene transfer frequencies. Our findings suggest that AAV transduction of CD34+ hematopoietic progenitor cells is efficient, can lead to stable integration in a population of transduced cells, and may therefore provide the basis for safe and efficient ex vivo gene therapy of the hematopoietic system.  相似文献   
995.
Noninfiltrating angiolipoma of the mediastinum   总被引:1,自引:0,他引:1  
Kline  ME; Patel  BU; Agosti  SJ 《Radiology》1990,175(3):737-738
A case of mediastinal angiolipoma in a 63-year-old man is described. A computed tomographic scan of the thorax demonstrated a large encapsulated mass with fatty and soft-tissue components near the esophagus. This appearance was considered suggestive of a liposarcoma. However, at surgery a benign noninfiltrating angiolipoma was found and removed. To the authors' knowledge, angiolipomas have not previously been reported to occur within the mediastinum.  相似文献   
996.
997.
To determine if magnetic resonance (MR) imaging techniques can be used to examine sites of embryo implantation in intact rats, pregnant animals were imaged with gadopentetate dimeglumine-enhanced MR imaging approximately 10 hours after initiation of implantation on day 5 of pregnancy. T1-weighted, three-dimensional SPGR (spoiled gradient-recalled acquisition in the steady state) sequences were used to image the volume of abdomen containing the uterine horns before and after injection of gadopentetate dimeglumine into a femoral venous catheter. While unenhanced images provided little detail in uterine tissue, analysis of the gadolinium-enhanced abdominal images with interactive vascular imaging allowed easy identification of sites of embryo implantation along both uterine horns in four of four pregnant rats. These punctate patterns of enhancement match those of macroscopic bluing after injection of Evans blue dye. Similar gadolinium-enhanced MR imaging of nonpregnant rats produced only a slight, generalized enhancement of entire uterine horns. The authors conclude that local increases in extracellular fluid volume, vascular permeability, and blood flow in the uterus may all contribute to the gadolinium enhancement of the implantation sites. They propose that this approach can be used in experimental settings to provide information regarding embryo implantation unaccessible with traditional approaches. In clinical settings, gadolinium-enhanced MR imaging may be used to examine potential causes of infertility, including luteal phase defects.  相似文献   
998.
The aim of the study was to assess the rehabilitation results in visually impaired patients with cochlear implants. Material consisted of 9 patients (2 with prelingual deafness, 3 with perilingual deafness, 4 with postlingual deafness) from 244 implanted persons in Poznań. METHODS: In all the patients the rehabilitation results were evaluated using Test of Auditory Perception of Speech (TAPS) and screening test. RESULTS: In the group of patients with pre- and perilingual deafness a little bit slower progress of rehabilitation was found, according to 117 persons with prelingual deafness and 34 persons with perilingual deafness without vision disorders. Within the group of patients with postlingual deafness important progress of rehabilitation was observed. Two brothers with Usher syndrome 1-2 months after speech processor switch-on reached the highest level of test, they could communicate with family. One person after 5 months of rehabilitation could talk by phone without any problems. In all implanted visually impaired patients improvement of auditory perception of speech was observed.  相似文献   
999.
Pseudoaneurysms complicating pancreatitis: detection by CT   总被引:3,自引:0,他引:3  
Complications of pancreatitis such as pseudocyst formation and abscess are well known to radiologists. Secondary formation of pseudoaneurysms has not been emphasized in the radiologic literature. The great morbidity and mortality associated with pseudoaneurysms emphasize the importance of early detection. Three patients are described whose angiographically proved pseudoaneurysms were demonstrated on contrast material-enhanced abdominal CT scans obtained for evaluation of pancreatitis. A homogeneously enhancing structure within or adjacent to a pancreatic pseudocyst or contiguous with a vascular structure should be considered highly suspicious for an associated pseudoaneurysm.  相似文献   
1000.
Poznań's program of cochlear and brainstem implantation: a general review   总被引:1,自引:0,他引:1  
The cochlear implantation program in Poznań started in January 1994. Within 8 years, 151 patients were implanted (149 cochlear and 2 auditory brain-stem implants). The implanted group comprised 111 children and 40 adults. We have extended the lower age limit for cochlear implant candidates, and the youngest implanted patient was 18-months-old at the time of surgery. We have also implanted six multi-handicapped subjects. All patients were implanted with different nucleus devices (22, 24 M, 24 K, 24 Contour, 24 Double Array and 24 ABI). Insertion of the Nucleus 24 Contour electrode carrier requires a little larger cochleostomy in comparison with conventional straight array. After insertion, the intraoperative measurements are taken (impedance telemetry, electrically evoked stapedius reflex and NRT). The day after surgery, each patient undergoes an X-ray examination (the cochleogram or cochlear view). The calculated length of the electrode array insertion was 12.75-24.0 mm (mean: 22.05 mm) and the degree of electrode rotation was 180-540 degrees (mean: 292.82 degrees). After speech processor switch-on, we performed NRT measurements. Our results indicated that the NRT threshold was in 51.4% of the dynamic range within the group of examined patients. The adults' progress of rehabilitation was checked during individual sessions. The rehabilitation of children included two rehabilitation schedules: continuous ones and weekly rehabilitation camps. The progress of the recovery process of implanted children enabled them to change their school profile from hearing impaired to mainstream. Voice rehabilitation is often monitored by acoustic analysis using the Multi Dimensional Voice Program (MDVP).  相似文献   
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