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Preliminary data using B72.3 murine monoclonal antibody labeled with iodine 125 suggested that both clinically apparent as well as occult sites of colorectal cancer could be identified intraoperatively using a hand-held gamma detecting probe. We report the preliminary data of a multicenter trial of this approach in patients with primary or recurrent colorectal cancer. One hundred four patients with primary, suspected, or known recurrent colorectal cancer received an intravenous infusion of 1 mg of B72.3 monoclonal antibody radiolabeled with 7.4 x 10 Bq of iodine 125. Twenty-six patients with primary colorectal cancer and 72 patients with recurrent colorectal cancer were examined. Using the gamma detecting probe, 78% of the patients had localization of the antibody in their tumor; this included 75% of primary tumor sites and 63% of all recurrent tumor sites; 9.2% of all tumor sites identified represented occult sites detected only with the gamma detecting probe. The overall sensitivity was 77% and a predictive value of a positive detection was 78%. A total of 30 occult sites in 26 patients were identified. In patients with recurrent cancer, the antibody study provided unique data that precluded resection in 10 patients, and in another eight patients it extended the potentially curative procedure.  相似文献   
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The Thy-l.1 molecule was isolated from the BW5147 murine lymphoblastoid cell line. The initial step in purification was the preparation of a crude plasma membrane fraction followed by acetone precipitation. The acetone pellet was solubilized using deoxycholate (DOC) and Thy-1.1 was purified by use of a Lens culinaris lectin affinity column and an AcA-34 gel filtration column. The purified glycoprotein with Thy-1.1 activity had a mol wt of approximately 25,000 daltons. The isolation of this molecule was effected by detecting Thy-I activity utilizing rabbit anti- mouse brain serum tested on rat thymocytes. Congenic anti-Thy-l.1 serum was ineffective in detecting Thy-l.1 after DOC solubilization. An antiserum prepared in rabbits to the purified Thy-1.1 was found to be cytotoxic to mouse and rat thymocytes. The cytotoxic activity of this antisera could be completely absorbed with AKR/Jax brain and thymus but was not absorbed by liver. In addition, AKR/Jax thymocytes totally absorbed all cytotoxic activity of the rabbit anti-purified Thy-1 serum for BW5147 cells suggesting that the cell line shares identical specificities with normal thymocytes. The purified Thy-1.1 molecule was able to totally absorb the cytotoxic activity of mouse congenic anti-Thy-1. These studies serve as a model for the isolation of other murine lymphoid cell surface components in quantities for detailed structural and functional analysis.  相似文献   
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Summary.  Introduction:  In some patients with mild hemophilia A, there are discrepancies between 1-stage (1-st) and 2-stage (2-st) factor VIII (FVIII) clotting assays, and also chromogenic assays for FVIII activity (FVIII:C). We examined whether thrombography could provide a better evaluation of the hemostatic status of these patients. Methods:  Two families with such discrepancies and markedly contrasting clinical histories were studied. Family X had no serious bleedings, in contrast to family Y. Sixty-one moderate/mild hemophiliacs without discrepancy and 15 healthy subjects served as controls. Calibrated automated thrombography was performed with platelet-rich plasma after one freeze-thawing cycle and low tissue factor concentration. Results:  The chromogenic FVIII:C levels were higher (0.90 ± 0.15 and 0.47 ± 0.13 IU mL−1) than the 1-st clotting ones (0.14 ± 0.05 and 0.10 ± 0.05 IU mL−1) in family X and Y, respectively ( P  < 0.001). Mean endogenous thrombin potential (ETP) was 1579 ± 359 n m  min−1 and 1060 ± 450 for healthy controls and hemophilic controls, respectively. For members of family X, the ETP values were 1188, 1317 and 2277 n m  min−1, whereas for those of family Y they ranged from 447 to 1122 n m  min−1. Two novel missense point mutations were evidenced: p.Ile369Thr in family X and p.Phe2127Ser in family Y. In family X, we postulate that the mutation is responsible for a delayed but non-deleterious FVIII activation. Conclusions:  Our results suggest that the hemostatic phenotype assessed by thrombography may be clinically relevant in moderate/mild hemophilic patients with discrepant FVIII:C results.  相似文献   
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No brain abnormalities are usually detected on conventional magnetic resonance imaging (MRI) in benign hereditary chorea (BHC); there are currently no studies with advanced techniques in literature. We investigated whether conventional and advanced MRI techniques could depict regional brain abnormalities in two familial BHC patients and 24 healthy controls. No brain abnormalities on conventional scans were detectable; also, no significant differences in fractional anisotropy of the basal nuclei were observed. Volumetric analysis showed a decreased volume of the striatum bilaterally compared with controls, whereas spectroscopy demonstrated a significant increased myoinositol/creatine ratio bilaterally, a reduction of choline/creatine ratio bilaterally, and of N‐acetyl‐aspartate/creatine in the right putamen. With the limits of the small sample size in the patient group, these data show that, despite the absence of macroscopic changes on conventional MRI, volumetric and metabolic abnormalities are present in the basal nuclei of BHC patients. © 2010 Movement Disorder Society.  相似文献   
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A review of antiviral therapies in the treatment of cytomegalovirus   总被引:3,自引:0,他引:3  
ABSTRACT: Cytomegalovirus (CMV) is a member of the herpesvirus family that is very prevalent world wide based on serologic testing. In immunocompromised persons CMV produces high rates of morbidity and mortality. Congenital CMV is the leading infectious cause of fetal abnormalities in the United States. Infection of human immunodeficiency virus (HIV) seropositive persons or transplant patients with CMV can produce retinitis, encephalitis, pneumonitis, hepatitis, gastrointestinal ulcerations, and cutaneous lesions. Three intravenous therapies are available for CMV infections: ganciclovir; foscarnet and cidofovir. Most recently a fourth antiviral agent was approved for intravitreal injection. This drug, fomivirsen, is the first antisense oligonucleotide available for therapeutic use. A number of other antiviral drugs and vaccines are currently under study.  相似文献   
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