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71.
Technical developments in MR angiography 总被引:6,自引:0,他引:6
CE MRA has evolved rapidly since the early studies by Prince et al [3]. Whereas many of the procedures in clinical use today rely heavily on the use of gadolinium contrast agents and standard. Fourier transform acquisition techniques, advances will have a significant impact on MRA by shortening the acquisition time, improving the reproducibility of the image-acquisition techniques, and improving spatial resolution or SNR. From a technical basis, shorter acquisition times associated with fast gradients are likely to improve spatial resolution and allow for acquisition of MR images over large FOVs. In addition, alternative k-space sampling techniques, such as parallel imaging and PR, are expected to further reduce acquisition time, while maintaining or improving spatial resolution. The approval and subsequent use of new contrast agents will also have a beneficial impact on the image quality of contrast-enhanced MRA applications. It is likely that these contrast agents will be coupled with advanced acquisition techniques to improve spatial resolution and technical success rates of MRA examinations. 相似文献
72.
Murine hindlimb reperfusion injury can be initiated by a self-reactive monoclonal IgM 总被引:4,自引:0,他引:4
BACKGROUND: Murine hindlimb reperfusion injury (I/R), is initiated by activation of the classical pathway of complement. Complement receptor-2 knockout mice (Cr2-/-) are protected from I/R injury due to defective B-1 cells with a resulting deficient natural immunoglobulin M (IgM) repertoire. Cr2-/- and wild type (WT) mice were studied to isolate the antibody or antibodies responsible for initiation of I/R. METHODS: IgM-secreting B-1 cell clones were produced with hybridoma technology from WT cells. Of 21 clones tested in murine I/R models, only 1 clone, CM22, was found to restore injury in protected mice. Cr2-/- mice reconstituted with IgM from individual clones, WT serum, or saline were subjected to 2 hours hindlimb ischemia and 3 hours reperfusion and compared with WT. RESULTS: Muscle injury in Cr2-/- mice reconstituted with CM22 was similar to injury in WT mice reconstituted with saline and Cr2-/- mice reconstituted with WT serum. This injury was 137% greater (P < .05) than in both Cr2-/- mice reconstituted with saline and those reconstituted with a different IgM clone, CM31. IgM and C3 deposition was found only on injured muscle of WT mice or Cr2-/- mice reconstituted with CM22 or WT serum. CONCLUSION: A single clone of self-reactive IgM, CM22, can initiate complement-dependent I/R injury. 相似文献
73.
Immunologic heterogeneity of diffuse large cell lymphoma 总被引:2,自引:0,他引:2
Freedman AS; Boyd AW; Anderson KC; Fisher DC; Pinkus GS; Schlossman SF; Nadler LM 《Blood》1985,65(3):630-637
The cellular lineage of 57 diffuse large-cell lymphomas (DLCLs) was determined using a panel of monoclonal antibodies directed against lineage-restricted and -associated T, B, and monocyte antigens. The majority (82%) were of B cell lineage as determined by the expression of sig and/or B1, with the remaining 16% being of T cell lineage and 2%, of monocyte-myeloid lineage. By the expression of other B cell- restricted and -associated antigens, two major and two minor subgroups could be identified. These subgroups expressed the following phenotypes: (1) B1+B4+sIG+B2- (51%); (2) B1+B4+sIg+B2+ (29%); (3) B1+B4+sIg-B2+ (10%); and (4) B1+B4-sIg+B2- (10)%. The morphology of transformed lymphocytes, the weak to absent expression of the early B cell antigens B2 and sIgD, and the absence of the late B cell differentiation antigens PCA-1 and PC-1 suggested that these tumors were the neoplastic counterparts of normal B cells at the mid-stages of differentiation. Further support for the notion that B-DLCLs correspond to transformed B lymphocytes was concluded from the observation that B cells could be identified in normal spleen that expressed the cell surface phenotype and morphological appearance of the majority of B- DLCLs. 相似文献
74.
Mapping of steroid 21-hydroxylase genes adjacent to complement component C4 genes in HLA, the major histocompatibility complex in man. 总被引:30,自引:12,他引:30
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M C Carroll R D Campbell R R Porter 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(2):521-525
The genes for four components (C) of complement in the human major histocompatibility complex (HLA) have been aligned previously in a series of overlapping cosmid cloned inserts. Those inserts, which contained the two C4 genes C4A and C4B, hybridized with human adrenal mRNA, indicating that they contain a gene expressed in the adrenal. The mRNA fraction of 2.4 kilobases (kb) hybridizes with genomic DNA of 4.5 kb, which is duplicated and lies about 1.5 kb 3' of both the C4A and the C4B complement genes. Sequencing of a 430-base section and comparison with the published cDNA sequence of bovine cytochrome P-450 21-hydroxylase, peptide sequences of porcine 21-hydroxylase, and a cDNA sequence of a rat liver cytochrome P-450 identified the gene as coding for human steroid 21-hydroxylase [steroid,hydrogen-donor:oxygen oxidoreductase (21-hydroxylating), EC 1.14.99.10]. Mapping of the gene was helped by use of a synthetic oligonucleotide based on the bovine cDNA sequence. 相似文献
75.
Endovascular versus open approach to aortic aneurysm repair surgery: rates of postoperative delirium
Konrad Salata BHSc Rita Katznelson MD W. Scott Beattie MD PhD Jo Carroll RN Thomas F. Lindsay MD George Djaiani MD 《Journal canadien d'anesthésie》2012,59(6):556-561
Purpose
Our objective was to compare open and endovascular aortic aneurysm repair with respect to postoperative delirium.Methods
After Institutional Ethics Review Board approval, we conducted a retrospective review of all patients who underwent abdominal and thoraco-abdominal aortic aneurysm repair surgery at Toronto General Hospital during June 2006 to December 2007. Patients were classed into either the OPEN or the endovascular (EVAR) group based on the type of surgery and were assessed for the presence of delirium after surgery. The NEECHAM Confusion Scale and the validated chart review instrument were used for diagnosis of delirium. Patients with dementia and/or abnormal levels of consciousness preoperatively were excluded.Results
There were 256 patients included in the study, 149 (58%) in the OPEN group and 107 (42%) in the EVAR group. Patients in the EVAR group were considerably older, 74 (10) yr vs 68 (9) yr, and they had shorter duration of surgery, 150 [119, 180] min vs 200 [165, 260] min, respectively, P?<?0.0001. Postoperative delirium was present in 43 (29%) patients in the OPEN group and 14 (13%) patients in the EVAR group (95% confidence interval [CI], 22 to 36 vs 95% CI, 7 to 19, respectively; P?=?0.003). Hospital length of stay was 8.3 [6.6, 13.4] days in the OPEN group and 4.5 [3.1, 6.4] days in the EVAR group, P?<?0.0001.Conclusions
Perioperative management of patients undergoing endovascular aortic aneurysm repair was associated with lower rates of delirium after surgery than that of patients undergoing open aortic aneurysm repair. 相似文献76.
Ultrasound scanning of the pelvis with an empty bladder permits a true frontal view of the uterus to be easily obtained. This view is comparable to the en face view seen at hysterography performed with contrast material. Good definition both of the endometrium and the uterine wall makes this the optimal method for the evaluation of an intrauterine contraceptive device. 相似文献
77.
Bello L Lucini V Giussani C Carrabba G Pluderi M Scaglione F Tomei G Villani R Black PM Bikfalvi A Carroll RS 《Neurosurgery》2003,52(1):177-85; discussion 185-6
OBJECTIVE: The biological features of malignant gliomas include high cell proliferation, extensive local infiltration of tumor cells into normal brain, and marked neovascularization. alphavbeta3 integrin is highly expressed in malignant gliomas and plays a role in glioma growth. This article investigates the in vitro and in vivo effects of a synthetic alphavbeta3 integrin inhibitor called IS20I on human malignant gliomas. METHODS: The in vitro effects of IS20I were studied by performing adhesion assays, competition studies, semi-in vivo angiogenic assays, and migration and proliferation assays. For the in vivo experiments, IS20I was administered systemically in nude mouse intracranial and subcutaneous malignant glioma models. RESULTS: IS20I reacted selectively to alphavbeta3 integrin in glioma cells and tissues. In vitro, IS20I strongly inhibited angiogenesis and simultaneously exhibited potent antimitotic and antimigratory effects on numerous tumor and endothelial cell lines. In addition, at high concentrations, IS20I induced endothelial and tumor cell apoptosis. In vivo, when IS20I was administered intraperitoneally in subcutaneous and intracranial nude mouse glioma models, it potently reduced malignant glioma growth. Inhibition levels of 76 and 82% were observed at concentrations of 1 and 5 mg/kg, respectively, in the U87 intracranial model. The suppression of tumor growth is associated with a decrease in tumor vascularity, an increase in apoptosis, and a decrease in tumor cell proliferation. CONCLUSION: This work expands the understanding of the effects of anti-alphavbeta3 integrin inhibitors on malignant gliomas. In addition to direct proapoptotic and antiangiogenic effects, IS20I inhibits tumor and endothelial cell proliferation and migration, resulting in a potent inhibition of glioma growth in vivo. 相似文献
78.
79.
To define the optimal methods of diagnosis and repair of ureteral and renal pelvic injuries, we reviewed the records of 18 patients with 19 collecting system injuries (16 penetrating, three blunt). Hematuria was absent in five of 16 patients. Intravenous urography was diagnostic of ureteral injury in three and normal or nondiagnostic in eight. Retrograde pyelography was performed in only one patient and was diagnostic of bilateral ureteral injury. Treatment consisted of primary repair (minimal or no debridement and closure) in 11 injuries, ureteroureterostomy (debridement and reanastomosis) in six, ureteroneocystostomy in one, and transureteroureterostomy in one. Ureteral stents were placed in 12 injuries, nephrostomy catheter in one, and both in two. Four patients had no form of diversion. Followup was available for 14 patients; serum creatinine values were normal in each. Results of imaging studies in 13 were normal in 11; one showed mild caliectasis and one a resolving urinoma. Both intravenous urography and initial urinalysis may be unreliable indicators of ureteral and renal pelvic injury, and high suspicion mandates exploration. Usually the urinary tract can be satisfactorily reconstructed. Satisfactory urinary diversion can be achieved in most cases with an internal ureteral stent. 相似文献
80.