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91.
Gatenby  RA; Moldofsky  PJ; Weiner  LM 《Radiology》1988,166(3):757-759
Tumor oxygen levels were measured with an electrode in 13 patients with colon carcinoma metastases. These measurements were correlated with images obtained with radiolabeled monoclonal antibody 1083-17-1A. Only those tumors or tumor regions with a mean PO2 of 16 mm Hg or greater were successfully imaged. Tumors and tumor regions with a mean PO2 of less than 16 mm Hg were not imaged, even when the presence of antigen was confirmed with biopsy. These data suggest that physiologic factors other than antigen expression may affect antibody uptake.  相似文献   
92.
Twenty patients underwent computed tomography (CT)-guided thin-needle biopsy of tumors of the had and neck without complication. This technique was found to have wide application in confirming the presence and extent of primary disease as well as documenting nodal and bony metastases not apparent clinically.  相似文献   
93.
Over a 5-year period 57Co-bleomycin scintigraphy for tumor detection was performed with a large-field-of-view gamma camera. The scintigrams of 268 patients with lung cancer, with a benign lesion, or with no abnormality in the chest, were reviewed. A sensitivity of 96% was found. In a group of 193 patients in whom a preoperative pathologic diagnosis could not be obtained sensitivity was 95%, specificity was 87%. Correlation between tumor size and tumor-to-non-tumor ratio was established for squamous cell carcinoma, adenocarcinoma, and small cell anaplastic carcinoma. Adenocarcinomas were smaller and showed lower tumor-to-non-tumor ratios than other histologic types. In squamous cell carcinoma a possible correlation between tumor-to-non-tumor ratio and histologic differentiation was investigated, but could not be established. It is concluded that 57Co-bleomycin scintigraphy is helpful in the evaluation of patients with possible lung cancer in whom a preoperative pathologic diagnosis cannot be obtained.  相似文献   
94.
A patient suffering from Lyme disease had cardiac conduction abnormalities, symptoms of arthritis, and myalgia. A Ga-67 image showed evidence of endomyocarditis, but intense skeletal muscle uptake pointed to Lyme myositis. Reference is made to two other case reports of Lyme myositis.  相似文献   
95.
Alaryngeal voice is usually accompanied by esophageal speech; however, about 40% of laryngectomy patients are unable to achieve adequate esophageal speech and must rely on mechanical devices for communication. A technique was developed for performing double-contrast studies of the hypopharynx, cervical esophagus, and pharyngo-esophageal segment using thick barium and the air normally injected for speech. Simultaneous audio and video recordings obtained during esophageal speech allowed correlation of the quality of speech with the motion of the pharyngo-esophageal segment. In 35 patients with various degrees of fluency in esophageal speech, normal and abnormal function of the pharyngo-esophageal segment was documented. Inadequate esophageal speech can be related to abnormal motion of the pharyngo-esophageal segment.  相似文献   
96.
97.
Lung perfusion scintigraphy with technetium 99m-labeled microspheres was performed in a series of 14 normal rats. The mean value of left lung perfusion was 36.9 ± 4.9% of total lung perfusion. Duplicate determinations on three possible error levels were evaluated statistically: (1) separation of the lung fields on the computer scintigram, (2) positioning of the animal under the gamma camera, and (3) measurement after a one-week interval. The determinations resulted in standard deviations of (1) 2.8%, (2) 0, and (3) 1.4%, respectively. These results are comparable with those of lung perfusion studies in dogs.Lung perfusion scintigraphy, chest roentgenography, and postmortem examination were used in the functional evaluation of two groups of left lung–transplanted rats: Group A (n = 12) had short-term follow-up and Group B (n = 11) had long-term follow-up. A common finding in Group A was a subnormally perfused and aerated graft, showing normal lung tissue for the most part at postmortem examination. In Group B, grafts were rarely perfused and aerated. At postmortem examination, they were fibrotic or abscessed, possibly due to chronic rejection. A good correlation was found between perfusion scintigraphy, chest roentgenography, and postmortem findings.  相似文献   
98.
Murine monoclonal antibodies of the immunoglobulin G2a isotype interact with human effector cells to mediate antibody-dependent cellular cytotoxicity (ADCC) directed against malignant cells which express antigens recognized by these antibodies. gamma-Interferon enhances these effects in vitro. In a Phase I trial of murine monoclonal antibody CO17-1A and recombinant gamma-interferon (rIFN-gamma), we demonstrated that low doses of rIFN-gamma were superior to high doses in augmenting ADCC mediated by treated patients' monocytes. These results formed the basis for a Phase II trial of CO17-1A combined with low dose rIFN-gamma. Nineteen patients with metastatic colorectal carcinoma were treated with four consecutive daily infusions of 1.0 X 10(6) IU/m2 rIFN-gamma, with 150 mg of CO17-1A administered on days 2, 3, and 4. Therapy was tolerated well. Peripheral blood mononuclear cells were purified from patient samples obtained at baseline and at 1, 4, or 24 h following the start of the first rIFN-gamma infusion and were tested for their ability to lyse 111In-labeled cells of the SW1116 colorectal line. Enhancement of monocyte ADCC was seen by 24 h, while lymphocyte ADCC and natural killer activity directed against K562 cells were enhanced to a lesser extent. Nonspecific lysis of SW1116 cells by effectors was not seen at the time points examined. While CO17-1A antigen expression was observed in most biopsies, 131I-labeled CO17-1A imaged positively in less than one-half of the organs known to harbor metastases, and therapeutic antibody delivery was not always demonstrated by immunoperoxidase staining techniques of tissue obtained following therapy. In antigen-positive lesions, tissue pO2 levels appear to identify lesions which would image positively. No objective responses were seen. Our findings suggest that prolonged therapy with low doses of rIFN-gamma potentiates ADCC but that physiological obstacles to therapeutic antibody delivery are significant. In order to evaluate the validity of this therapeutic approach, measures to enhance antibody delivery are needed, starting with systematic evaluations of therapy with escalating doses of CO17-1A combined with low dose rIFN-gamma therapy.  相似文献   
99.
100.
In a patient with a paraganglioma at the carotid bifurcation, intense uptake of meta-[I-131]iodobenzylguanidine (I-131 MIBG) in the tumor was found. There was no clinical or biochemical evidence for catecholamine secretion by the tumor, although analysis of the tissue revealed that catecholamine biosynthesis took place. We conclude that accumulation of I-131 MIBG may occur in a paraganglioma, but does not necessarily indicate endocrine activity of the tumor.  相似文献   
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