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We examined the mechanisms of the inhibition of DNA synthesis by a new platinum compound, (-)-( R )-2-aminomethylpyrrolidine(1,1-cyclobutane-dicarboxylato)-2-platinum(II) monohydrate (DWA-2114R), a derivative of the antitumor drug cis- diamminedichloroplatinum(II) (CDDP), using prokaryotic and eukaryotic DNA polymerases. Preincubating activated DNA with CDDP or DWA-2114R reduced its template activity for prokaryotic and eukaryotic DNA polymerases in a dose-dependent manner. DWA2114R required six times greater drug concentration and two times longer incubation time to show the same decrease of the template activity compared to CDDP. Treatment of primed pUC118 ssDNA templates with the two drugs followed by second-strand synthesis by prokaryotic and eukaryotic DNA polymerases revealed that DWA2114R bound to DNA in a similar manner to CDDP and these adducts blocked DNA elongation by DNA polymerases of eukaryotes as well as of prokaryotes. With these two drugs, the elongations by E. coli DNA polymerase I (Klenow fragment), T7 DNA polymerase and calf thymus DNA polymerase α were strongly arrested at guanine-guanine sequences (GG). Stop bands were also observed at adenine-guanine sequences (AG) guanine-adenine-guanine sequences (GAG) and mono-guanine sequence (G). Calf testis DNA polymerase β was also arrested efficiently at AG, GAG and G, but much more weakly at GG. This pattern was common to DWA2114R and CDDP.  相似文献   
3.
From January 1986 to December 1988, a prospective trial of transcatheter arterial treatment was carried out for hepatocellular carcinoma (HCC). Two hundred seventy-five patients were included. Okuda's staging system was employed. Patients with Stage I and II HCC were treated by transcatheter arterial embolization (TAE) with a gelatin sponge containing an anti-cancer agent (protocol 1a); a gelatin sponge and iodized oil mixed with an anti-cancer agent (protocol 1b); or iodized oil mixed with an anti-cancer agent (protocol 2). Patients with Stage III HCC were treated with iodized oil with anti-cancer agent (protocol 2). As an exception, patients with an unsuccessful superselective catheterization into the proper hepatic artery by Seldinger technique or obstruction of the main trunk of the portal vein were treated with percutaneous transcatheter arterial infusion into the common hepatic artery regardless of stage (protocol 3). Tumor type and extension, area of tumor involvement, portal vein involvement, method of treatment, and presence of ascites and icterus were found to be the significant factors for an initial response to therapy. Treatment method was the most important factor. Respective survival rates at 1 and 2 years were 70.9% and 55.3% for protocol 1a; 62.3% and 43.8% for protocol 1b; 37.8% and 18.3% for protocol 2; and 16.5% and 0% for protocol 3. Many factors proved to significantly influenced prognosis; however, tumor type had the most important prognostic significance followed by AFP value, ascites, treatment protocol, and area of tumor involvement.  相似文献   
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Patients with head injury may experience olfactory dysfunction. Unfortunately, little is known about changes in the olfactory neuroepithelium caused by intracranial olfactory nerve injury and hemorrhage. We performed olfactory nerve section or bulbectomy in 53 Mongolian gerbils and subjected the olfactory neuroepithelium to immunohistochemical analysis. A decrease or disappearance of the antiserum to an olfactory marker protein containing olfactory receptor neurons was evident in the sectioned group. Degeneration of the olfactory neuroepithelium contralateral to olfactory nerve injury was also noted in animals with perineural hemorrhage. These findings suggest that olfactory dysfunction may occur not only with nerve injury but also secondary to intracranial hemorrhage.  相似文献   
6.
Neoplastic angioendotheliosis has rarely been described as a respiratory disease. A patient is described with pulmonary vascular involvement induced by neoplastic angioendotheliosis in pulmonary vessels.  相似文献   
7.
Spinal cord compression is an extremely serious complication of hereditary multiple exostoses (HME). A case of HME with compression of the cervical spinal cord is reported. Complete recovery following surgery was achieved. A review of the relevant literature revealed 51 previous cases of HME with cord/cauda equina compression. Most patients were under 30 years of age with more men affected than women. The family history was positive in 60%. The cervical and thoracic areas were predominantly affected, with the symptoms usually developing slowly. Recovery following surgery is to be expected in the majority of cases. In patients with HME and suffering from neurological symptoms, the possibility of spinal cord compression should be considered. Prompt diagnosis and surgical excision provide the best prognosis.  相似文献   
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Carbon fibers with fibrin glue were used as electrodes for diaphragm pacing. The electrodes were applied to three mongrel dogs and the effectiveness was tested. The carbon leads were glued to phrenic nerves by means of the fibrinogen and thrombin bilaterally. The tidal volumes and threshold current level for stimulation were measured at various time up to 9 weeks after implantation. Effective contraction of diaphragm were observed for 9 weeks. By using this electrode, the exfoliation of the nerve is not necessary, the nerve can be maintained in an intact state, and the risk of the implanting operation can be minimized.  相似文献   
10.
Phase I study of E1040, a new parenteral cephem antibiotic   总被引:1,自引:0,他引:1  
The safety and pharmacokinetics of E1040, a new injectable cephem antibiotic, were evaluated in healthy volunteers. In single-dose studies, 125, 250, 500, 1000 and 2000 mg of E1040 were administered by I.V. infusion over 1 hour. Results of 5 minutes I.V. infusions of 500, 1000 and 2000 mg of the drug were also studied. Plasma concentration-time profiles were well suited to a two-compartment open model. The half-life of elimination from plasma was 1.85 +/- 0.16 hours, and the Cmax and AUC paralleled the doses given. The mean urinary recovery within the first 24 hours was 85.7 +/- 6.43% of the dose. In a multiple-dose study, 2000 mg of E1040 (I.V. over 1 hour) was administered every 12 hours (total 9 times) and no abnormal accumulation of the drug in plasma was observed. There were no significant differences in plasma levels or in urinary recoveries between single- and multiple-dose regimens. There were no subjective or objective abnormal findings definitely attributable to the drug except that one subject given 250 mg over 1 hour reported diarrhea, and another complained of nausea during the infusion of 2000 mg over 5 minutes. From these results E1040 was concluded to be safe and well tolerated.  相似文献   
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