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Summary. The L1 capsid proteins derived from human papillomavirus (HPV) type 33 were expressed in a recombinant baculovirus system using Sf9 insect cells. Selected sera originating in women from case-control study carried out in Spain and Colombia found negative and positive for HPV16, 18, 31, 33 and 35 DNA were tested in ELISA for the presence of IgG antibodies to purified virus-like particles (VLP). The reactivity was type-restricted with the possible exception of HPV31. Received July 4, 1996 Accepted September 17, 1996  相似文献   
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The present study was undertaken to investigate the effect of biphenyl dimethyl dicarboxylate (PMC) on the humoral immunosuppression by ethanol (EtOH) in ICR mice. PMC at a dose of 6 mg/kg was orally administered to mice daily for 28 consecutive days, and the control mice were given vehicle. Mice treated with EtOH were given freely with 20% EtOH instead of water. The results of this study are summarized as follows; a gain of body weight and the relative weights of spleen and liver were significantly increased by combination of PMC and EtOH, as compared with those in mice treated with EtOH alone. Splenic plaque forming cells (PFC) and hemagglutination (HA) titers to sheep red blood cells (SRBC), and the secondary IgG antibody response to bovine serum albumin (BSA) were decreased by the treatment of EtOH alone, then restored to normal level by PMC treatment. The elevations of serum glutamic-pyruvic transaminase (S-GPT) and total protein levels caused by EtOH were reduced to normal level by the combination of PMC and EtOH. In addition, lower serum albumin and A/G ratio were also increased to normal level. These findings indicate that PMC has a protective effect against EtOH-induced humoral immunosuppression.  相似文献   
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Wai Mun Huang 《Virology》1975,66(2):508-521
During the prereplicative period after the infection of Escherichia coli by phage T4, more than 50 proteins are synthesized. Many of them have been identified with their corresponding genes. Among them, at least 13 are selectively enriched in the membrane preparation. They include the products of the two rII genes, genes 39, 52 (DNA-delay), and others not yet identified. The majority of these proteins (90%) are extractable by the detergent, sarkosyl, and are possibly associated with the inner or cytoplasmic membrane. Based on their electrophoretic migration in SDS-polyacrylamide gels and on their tryptic fingerprints, these proteins are found to be phage induced. Two of the newly synthesized proteins that are selectively enriched in the cell wall or outer envelope fraction are found to be identical with two envelope proteins of the host cell. They are continually synthesized after phage infection although general host protein synthesis is shut off.  相似文献   
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The purpose of this study is to determine the efficacy of bioactive calcium phosphate obtained from porcine cancellous bone for the treatment of bone defects and nonunion. Porcine cancellous bone blocks were heat treated at 1300 degrees C for 2 h. The chemical composition, calcium-to-phosphate ratio, and microstructure of the porcine bone blocks were examined. For in vivo implantation, bone defects were created on the anteromedial aspect of the proximal tibia in seven beagle dogs and the xenograft bone blocks were placed into these defects. Plain radiographs were taken at 2-week intervals for roentgenographic evaluation. At 12 weeks, the specimens were stained with hematoxylin and eosin (H&E). The composition and morphology of heat-treated porcine cancellous bone were found to be similar to heat-treated human cancellous bone. Radiographs showed union between the host bone/bone-block interfaces. At 12 weeks, uniform and substantial new bone formation was observed. It is concluded that heat-treated porcine cancellous bone demonstrated effective osteoconductivity. This high-temperature heat-treatment technique has several advantages, including decreased risk of disease transmission and immunoreactivity, while also offering excellent biocompatibility.  相似文献   
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Despite the abundant evidence of high allelic loss of chromosome arm 14q in human cancers, tumor-suppressor genes mapped to this chromosome have yet to be identified. To narrow the search for candidate genes, we performed monochromosome transfer of chromosome 14 into an esophageal carcinoma cell line, SLMT-1 S1. Statistically significant suppression of the tumorigenic potential of microcell hybrids containing the transferred chromosome 14 provided functional evidence that tumor-suppressive regions of chromosome 14 are essential for esophageal cancer. Tumor segregants emerging in nude mice during the tumorigenicity assay were analyzed by detailed PCR-microsatellite typing to identify critical nonrandomly eliminated regions (CRs). A 680-kb CR mapped to 14q32.13 and an approximately 2.2-Mb CR mapped to 14q32.33 were delineated. Dual-color BAC FISH analysis of microcell hybrids and tumor segregants verified the selective loss of the 14q32.13 region. In contrast, similar transfers of an intact chromosome 11 into SLMT-1 S1 did not significantly suppress tumor formation. These functional complementation studies showing the correlation of tumorigenic potential with critical regions of chromosome 14 validated the importance of the 14q32 region in tumor suppression in esophageal cancer. The present study also paved the path for further identification of novel tumor-suppressor genes that are relevant to the molecular pathogenesis of esophageal cancer.  相似文献   
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The effect of some metallocenes such as ferrocene (Fe(C5H5)2), nickelocene (Ni(C5H5)2), and cobaltocene (Co(C5H5)2), on the vinyl polymerization initiated with bis(ethyl acetoacetato)-copper(II) (Cu(eacac)2) was investigated. Co(C5H5)2 was found to exert a markedly accelerating effect on the polymerization of methyl methacrylate (MMA) with Cu(eacac)2. The polymerization of MMA with the system Co(C5H5)2/Cu(eacac)2 at 50°C was found to be fairly affected by the solvent used. The results of copolymerization of MMA with styrene (St) and the effect of hydroquinone (HQ) on the polymerization of MMA with Co(C5H5)2/Cu(eacac)2 showed that the polymerization proceeds via a radical mechanism. The polymerization of MMA with Co(C5H5)2/Cu(eacac)2 was studied kinetically in acetone. The overall activation energy of the polymerization was calculated to be 86,3 kJ/mol (20,6 kcal/mol). This value was somewhat higher than that (17,6 kcal/mol) obtained for the polymerization of MMA with Cu(eacac)2 alone. The polymerization rate (Rp) is represented by the following equation: Rp = k[Co(C5H5)2]0,5 [Cu(eacac)2]0,2 [MMA]1,3. The high order in monomer concentration suggests a participation of the monomer in the initiation process of this polymerization. This is supported by the examination of the ESR spectrum of the system Co(C5H5)2/Cu(eacac)2/MMA/acetone, where reduction of Cu(II) to Cu(I) occurs. To elucidate the initiation mechanism, the spin trapping technique was applied to the system Co(C5H5)2/Cu(eacac)2/methyl acrylate. From these results, an initiation mechanism for the binary initiator system Co(C5H5)2/Cu(eacac)2 is proposed and discussed.  相似文献   
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BackgroundLighter weight and lower modulus are potential advantages of titanium (Ti) implants over cobalt chrome (CoCr) implants in total knee arthroplasty (TKA). This study was conducted to determine whether Ti implants in TKA resulted in better clinical outcomes and radiologic results.MethodsOne hundred and eight patients (216 knees) with knee arthritis warranting bilateral primary TKA were randomly allocated to undergo Ti rotating-platform TKA in one knee and CoCr rotating-platform TKA in the contralateral knee. The mean follow-up period was 5.3 years (range, 1-7 years). The weight of Ti implants was one-third lighter than that of CoCr implants (133.9 g vs 390.1 g, P < .01). Clinical outcomes were evaluated using clinical scores, patient preferences (lightness, comfort, naturalness, and satisfaction), gait analysis (kinetic and kinematic data), range of motion, and degree of pain. Radiologic results were evaluated based on the radiolucent line (RLL), degree of medial tibial bone loss, and loosening as seen on X-ray.ResultsNo significant differences were observed in clinical scores or patient preference. Regarding implant weight, approximately 70% of patients did not perceive the Ti implant as lighter. No significant differences were observed in gait analysis, range of motion, or degree of pain. The RLL was seen in 9% of the Ti implant group and 19% of the CoCr implant group.ConclusionThe lighter Ti implant did not show any clinical benefit over CoCr implants. The lightness of the Ti implant is not sufficient to matter or be noticeable. However, the Ti implant showed lower rate of RLL than the CoCr implant.Level of Evidencelevel I, randomized controlled trial.  相似文献   
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