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101.
The authors describe their preliminary experience with the use of superparamagnetic magnetic resonance (MR) imaging contrast media for suppression of signal from flowing blood. The goal of this work was to determine if a superparamagnetic contrast agent could successfully eliminate blood signal during cardiac-gated MR imaging, thereby eliminating or reducing flow artifacts associated with the complex and variable hemodynamics within the heart chambers. Imaging and data analysis were performed in 17 dogs subjected to experimental myocardial infarction as part of a parallel project. Six doses (0.2, 1, 2, 3.5, 4, 5, and 10 mg/kg) of AMI-25, an experimental contrast agent, were used in the study. Spin-echo imaging was performed immediately before and every 5 minutes (for an average of 25 minutes) after bolus injection of the contrast agent. Variations in the image signal-to-noise ratio relative to a baseline (before injection of contrast agent) image were assessed as a function of dose and time. Preliminary results suggest that a considerable reduction in blood flow artifacts and, hence, increases in image signal-tonoise ratio can be achieved at doses greater than or equal to 3.5 mg/kg, for approximately 20 minutes after injection. Doses equal to or less than 2 mg/kg and images obtained more than 20 minutes after injection (regardless of dose) did not reliably show hemodynamic artifact suppression. 相似文献
102.
Tsuyoshi Satoh Tadashi Watanabe Masanori Tadokoro Junichi Sakamoto Hiroki Murayama Katsuki Itoh Sadayuki Sakuma Hiroshi Takagi 《Cancer science》1992,83(4):379-386
Anti-carcinoembryonic antigen monoclonal antibody (MAb) CEA102 was produced by immunization with purified CEA and the specific accumulation of radiolabeled CEA102 in colorectal cancers was investigated by autoradiography of surgical specimens using Fuji Computed Radiography (FCR). Five patients with colorectal cancer were injected intravenously with 131 I-labeled intact CEA102 or its F(ab')2 . Primary tumor and liver metastases were successfully detected by external scanning with a gamma camera in 4 cases. Autoradiographic study of the surgical specimens using FCR showed predominant localization of 131 I-labeled CEA102 in primary tumors and liver metastases in all cases. Even a small liver metastasis (0.5 cm) was clearly visualized in the autoradiogram by FCR. The pixel distribution curves of the density of the respective tissues in the autoradiograms by FCR showed the heterogeneity of the distribution of administered radiolabeled MAb in individual tumors, but the density of the tumors was higher than that of the normal tissues. In the quantitative distribution analysis of CEA102, the uptake of the primary tumor (mean 1.10%ID/kg) was ten-fold greater than that of the normal colon mucosa (mean G.10%ID/kg). These results revealed that the application of MAb has great potential in radioimmunodetection as well as in antibody-directed therapy. 相似文献
103.
A murine monoclonal antibody (MDR3M) (isotype: IgM) reactive with mdr3 gene product was generated by immunizing mice with mdr3 -specific peptide (H2 N-12 WRPTSAEGDFELGISSKQKRKKTKTVKMI41 G-COOH) and hybridizing the primed mouse splenic B cells with X63-Ag8,6.5.3 mouse plasmacytoma cells. MDR3M did not cross-react with mdr1 gene product. This monoclonal antibody may be useful for analyzing the role of mdr3 gene product in cells and tissues. 相似文献
104.
Declan Donovan BSc Dr. Judith H. Harmey PhD Deirdre Toomey BSc D. Henry Osborne MCh H. Paul Redmond MCh David J. Bouchier-Hayes MCh 《Annals of surgical oncology》1997,4(8):621-627
Background: Angiogenesis is essential for tumor growth and metastasis. Vascular endothelial growth factor (VEGF) is the most potent angiogenic
factor identified to date. TGFβ-1 acts as an indirect angiogenic agent.
Methods: VEGF and TGFβ-1 were measured in the serum of breast cancer patients and agematched controls and in tumor tissue of cancer
patients by ELISA. VEGF protein and mRNA expression by breast tumor cell lines were examined, and the effect of TGFβ-1 on
VEGF production in these cells was assessed.
Results: VEGF levels were significantly higher (P=.03) in the serum of patients with breast cancer compared to age-matched controls. A positive correlation was found between
serum (r=0.539) and tumor tissue (r=0.688) levels of VEGF and TGFβ-1. Metastatic MDA-MB-231 breast cancer cells produce more
VEGF than do the primary BT474 cells. TGFβ-1 significantly (P<.05) increased production of VEGF.
Conclusions: Breast cancer cells constitutively produce VEGF protein and mRNA. There is a relationship between VEGF and TGFβ-1 levels
in breast cancer patients, and TGFβ-1 regulates VEGF expression by breast cancer cells.
Presented at the 50th Annual Cancer Symposium of the Society of Surgical Oncology, Chicago, Illinois, March 20–23, 1997. 相似文献
105.
106.
射频闭合与传统剥脱术治疗下肢静脉曲张的对照研究 总被引:7,自引:0,他引:7
目的评价射频闭合(radiofrequency endovenous obliteration,RFO)的疗效。方法 56例(56条肢体)大隐静脉曲张患者随机分为两组,每组28例。RFO组利用射频能量使大隐静脉全程闭合,静脉剥脱组用传统方法高位结扎剥脱大隐静脉。两组病例小腿散在的曲张浅静脉均采用点式剥脱处理。比较两组病例的切口数、术后疼痛、平均住院日和短期疗效等情况。结果 RFO组平均切口少、术肢疼痛轻、无皮下血肿,术后平均住院日(2.50±1.00)d。静脉剥脱组的术后平均住院日(4.14±0.85)d。结论 RFO闭合大隐静脉具有创伤小、恢复快、腿部少留瘢痕等优点,是一种可部分替代传统大隐静脉高位结扎剥脱术的有效方法。 相似文献
107.
We report a novel double wire technique for ipsilateral access of the external iliac/common femoral artery transition side-branches in a patient with active extravasation. The case is noteworthy in that asymptomatic extravasation was noted in both the inferior epigastric and deep circumflex iliac branches on femoral angiography prior to intraaortic balloon pump insertion following emergent diagnostic left heart cathetrization. We speculate the side branch injury was related to the J-wire and describe how this complication may be best treated by the ipsilateral technique reported herein. 相似文献
108.
幕上星形细胞肿瘤MRI表现与VEGF、P16、Ki-67相关性研究 总被引:1,自引:0,他引:1
探讨星形细胞肿瘤MRI表现与P16、Ki—67、血管内皮生长因子(vascular endothelial growth factor,VEGF)表达的相关性。材料和方法:收集我院术前经MRI诊断并经手术病理证实的幕上星形细胞肿瘤53例,行常规平扫描后静脉注射Gd—DTPA增强成像;同时采用HE染色及链菌素生物素—过氧化酶连接法进行VEGF、Ki—67、P16的免疫组织化学染色,测定它们的表达指数。结果:星形细胞肿瘤的信号不均匀性、坏死、水肿、占位效应、强化程度与VEGF、Ki—67、P16的表达相关,且随着星形细胞肿瘤恶性程度的增高VEGF、Ki—67的表达增加;P16的表达率降低。结论:星形细胞肿瘤的MRI表现与VEGF、Ki—67、P16的表达密切相关,MRI可以间接判断星形细胞肿瘤的某些生物学行为。 相似文献
109.
Multiple routes of vascular access are required in children undergoing bone marrow transplantation to facilitate total parenteral nutrition (TPN); blood withdrawal; and administration of blood products, antibiotics, fluids, and immunosuppressive drugs. Placement of multiple catheters frequently requires multiple venotomies in separate vessels. We have found that both a Broviac catheter and pediatric dual-lumen Raaf catheter can be placed through separate venotomies in the external jugular vein, which provides sufficient routes of vascular access without complications. This technique places only one vessel at risk while minimizing the chance for infection by utilizing two exit sites. We consider this to be the procedure of choice in young patients requiring multiple routes of vascular access. 相似文献
110.
Carbamazepine Side Effects in Children and Adults 总被引:9,自引:8,他引:1
John M. Pellock 《Epilepsia》1987,28(S3):S64-S70
Summary: Most of the side effects associated with carbamazepine (Tegretol® , USP, Geigy Pharmaceuticals) therapy are mild, transient, and reversible with an adjustment in dosage or rate of dosage increase. Direct reports to Geigy Pharmaceuticals for the period 1975 to 1986 totaled 371 hematologic, 396 dermatologic, and 156 hepatic and pancreatic occurrences out of more than 4 million patients treated. These include 27 cases of aplastic anemia and 10 of agranulocytosis. In a study of the incidence of side effects in 220 children below the age of 16 years who were receiving carbamazepine, drowsiness, loss of coordination, and vertigo were the most commonly observed side effects and were almost always transient and dose related. The findings of this study are comparable with those of other series assessing carbam-azepine-associated adverse reactions in children and adults. Overall, 30 to 50% of children and adults were reportedly free of side effects in these studies. Recommendations for carbamazepine therapy include education of patients and parents in the nature and likelihood of possible serious adverse reactions and routine monitoring to detect laboratory abnormalities. 相似文献