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51.
A comprehensive anatomic and radiographic analysis of the peribursal fat plane in 12 cadavers confirmed that the fat plane seen on radiographs represents extrasynovial fat lining the subacromial bursa and documented the anatomic relations of the bursa. A three-part retrospective clinical evaluation of rotator cuff tears, calcific tendinitis, and rheumatoid arthritis was performed. Two osteoradiologists blindly graded the appearance of the peribursal fat plane with the shoulder in external versus internal rotation in 21 patients with arthrographically intact rotator cuffs and 21 patients with disrupted rotator cuffs. The peribursal fat plane was seen better with disrupted rotator cuffs. The peribursal fat plane was seen better with the shoulder in internal rotation and was seen in 60% of control subjects but only 21% of patients with rotator cuff tears. Partial or complete obliteration of this fat plane is a sensitive (79%) but less specific (60%) indicator of rotator cuff tears. Obliteration of the peribursal fat plane by inflammatory processes in adjacent tissues, including calcific tendinitis and rheumatoid arthritis, occurred with a high frequency.  相似文献   
52.
Telen  MJ; Palker  TJ; Haynes  BF 《Blood》1984,64(3):599-606
We have previously shown that a murine monoclonal antibody (A3D8) identifies a human erythrocyte protein antigen whose expression is regulated by the Lutheran inhibitor [In(Lu)] gene. In the present study, we demonstrated by immunoprecipitation and Western blot techniques that the antigen defined by A3D8 was on an 80-kD erythrocyte membrane protein. A second 170-kD protein was coprecipitated with the 80-kD protein but failed to show antigen activity by Western blot analysis. The 170-kD protein, when analyzed by sodium dodecyl sulfate- polyacrylamide gel electrophoresis in two dimensions, was composed of 50- and 30-kD disulfide-linked subunits. In(Lu) Lu[a-b-) erythrocytes differed from Lu(a+b+) or Lu(a-b+) erythrocytes in that In(Lu) deoxycholate erythrocyte membrane extracts contained trace amounts of immunoprecipitable 80-kD protein compared with detergent-solubilized erythrocyte membrane extracts prepared from Lu(a+b+) or Lu(a-b+) subjects.  相似文献   
53.
Deegan  MJ; Abraham  JP; Sawdyk  M; Van Slyck  EJ 《Blood》1984,64(6):1207-1211
Chronic lymphocytic leukemia (CLL) is generally considered a nonsecretory B cell immunoproliferative disorder. Conventional electrophoretic and immunoelectrophoretic methods have revealed serum monoclonal proteins in less than 10% of these patients. However, there is increasing experimental evidence from in vitro studies demonstrating that CLL cells may secrete immunoglobulins, particularly free light chains. We examined the serum and urine of 36 consecutive CLL patients for monoclonal proteins using sensitive immunochemical methods (high resolution agarose gel electrophoresis combined with immunofixation). The results obtained were correlated with the Rai stage, quantitative immunoglobulin levels, and lymphocyte membrane immunoglobulin phenotype of the leukemic cells. Twenty-three monoclonal proteins were identified in the serum or urine of 22 patients, an incidence of 61%. Six patients had serum monoclonal proteins, seven had only urinary monoclonal proteins, and nine had monoclonal proteins in serum and urine. In every instance the monoclonal protein was the same light chain type as expressed on the leukemic cells. Our findings suggest that the monoclonal proteins observed in the serum or urine of CLL patients are secretory products of the tumor cells and that their discovery is a function of the sensitivity of the method used for their detection.  相似文献   
54.
Lymphoblasts in bone marrow samples, obtained from 43 children with acute lymphoblastic leukemia at diagnosis, were incubated with 1.0 mumols/L [3H] methotrexate for 24 hours in vitro. Nonexchangeable methotrexate and methotrexate polyglutamates were separated and quantitated. Event-free survival at 5 years was 38% +/- 9% for all 43 patients (27 failures), and 44% +/- 10% for the 35 with non-T, non-B- cell acute lymphoblastic leukemia (20 failures). Of these 35 children, those whose lymphoblasts accumulated more than 100 pmol methotrexate and 500 pmol methotrexate polyglutamates per billion cells experienced better 5-year event-free survival than those whose lymphoblasts did not (65% +/- 12% v 22% +/- 9%, P = .010). This difference characterized "good-risk" patients who were female (P = .014), less than age 7 at diagnosis (P = .005), or had low initial white blood cell counts (less than 20 X 10(9)/L, P = .018). Findings were similar for the 43 children with acute lymphoblastic leukemia and for the "good-risk" children in this total group. Thus, the ability of lymphoblasts to accumulate methotrexate and form methotrexate polyglutamates may be important to the curative properties of current therapy of acute lymphoblastic leukemia in children, particularly for "good-risk" patients. In such patients, inherent rather than acquired drug resistance may be the initial event leading to treatment failure.  相似文献   
55.
Lymphangiomas in children: MR imaging   总被引:9,自引:0,他引:9  
Seventeen lymphangiomas in 15 patients were imaged with magnetic resonance (MR) to define the nature, extent, and anatomic relationships of these lesions. The MR and pathologic findings were then compared to determine the histologic basis for the signal-intensity characteristics of these lesions. The signal intensity of 13 lesions was similar to or slightly less than that of muscle on T1-weighted images and greater than that of fat on T2-weighted images. This appearance correlated with the presence of ectatic lymphatic channels containing clear fluid on histologic section. Four lymphangiomas had high signal intensity, approximately equal to that of fat, on T1-weighted images, reflecting the presence of clotted blood or small cystic spaces with a higher ratio of fat to fluid. Sixteen of 17 lesions had visible septations on MR images. The authors' experience suggests that most lymphangiomas have a characteristic appearance on MR images. The information obtained with MR imaging can help in providing a preoperative diagnosis, in planning surgical resection, and in defining recurrence.  相似文献   
56.
57.
Bacteriophage therapy (BT) uses bacteriophages to treat pathogenic bacteria and is an emerging strategy against multidrug‐resistant (MDR) infections. Experience in solid organ transplant is limited. We describe BT in 3 lung transplant recipients (LTR) with life‐threatening MDR infections caused by Pseudomonas aeruginosa (n = 2) and Burkholderia dolosa (n = 1). For each patient, lytic bacteriophages were selected against their bacterial isolates. BT was administered for variable durations under emergency Investigational New Drug applications and with patient informed consent. Safety was assessed using clinical/laboratory parameters and observed clinical improvements described, as appropriate. All patients received concurrent antibiotics. Two ventilator‐dependent LTR with large airway complications and refractory MDR P. aeruginosa pneumonia received BT. Both responded clinically and were discharged from the hospital off ventilator support. A third patient had recurrent B. dolosa infection following transplant. Following BT initiation, consolidative opacities improved and ventilator weaning was begun. However, infection relapsed on BT and the patient died. No BT‐related adverse events were identified in the 3 cases. BT was well tolerated and associated with clinical improvement in LTRs with MDR bacterial infection not responsive to antibiotics alone. BT may be a viable adjunct to antibiotics for patients with MDR infections.  相似文献   
58.
BackgroundMinimal invasive surgery (MIS) is increasingly used for the correction of congenital diaphragmatic hernia (CDH) and esophageal atresia (EA). It is important to master these complex procedures, preferably preclinically, to avoid complications. The aim of this study was to validate recently developed models to train these MIS procedures preclinically.MethodsTwo low cost, reproducible models (one for CDH and one for EA) were validated during several pediatric surgical conferences and training sessions (January 2017–December 2018), used in either the LaparoscopyBoxx or EoSim simulator. Participants used one or both models and completed a questionnaire regarding their opinion on realism (face validity) and didactic value (content validity), rated on a five-point-Likert scale.ResultsOf all 60 participants enrolled, 44 evaluated the EA model. All items were evaluated as significantly better than neutral, with means ranging from 3.7 to 4.1 (p < 0.001). The CDH model was evaluated by 48 participants. All items scored significantly better than neutral (means 3.5–3.9, p < 0.001), with exception of the haptics of the simulated diaphragm (mean 3.3, p = 0.054). Both models were considered a potent training tool (means 3.9).ConclusionThese readily available and low budget models are considered a valid and potent training tool by both experts and target group participants.Type of studyProspective study.Level of evidenceLevel II.  相似文献   
59.
60.
Sickle cell disease: imaging of cerebrovascular complications   总被引:3,自引:0,他引:3  
Moran  CJ; Siegel  MJ; DeBaun  MR 《Radiology》1998,206(2):311
  相似文献   
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