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111.
The aim of this study was to develop as effective as possible autologous tumor vaccine which would be at the same time easy to produce, highly controllable, and without undesired side effects on normal tissue. Therefore, irradiated autologous - syngeneic B-16 tumor cells admixed with a non-specific immunomodulator MVE-2 (a polymer fraction of 1,2-co-polymer of divinyl ether and maleic anhydride) were used for subcutaneous (s.c.). or intraperitoneal (i.p.) prevaccination of experimental mice. Compared to the control mice, a statistically significant delay in tumor development of s.c. tumors was achieved in prevaccinated mice (p<0.05). An even better effect was observed in mice challenged i.p. with viable tumor cells. Using a single prevaccination complete protection was obtained in between 40-85% of the experimental mice. When the survivors from the groups injected once with the tumor vaccine were rechallenged with viable tumor cells (101 day after the first tumor challenge, no additional prevaccination), 15.7% remained free of tumor, while the survivors from the groups injected with the tumor vaccine twice and 101 day later rechallenged with viable tumor cells remained free of tumor in 60% of the cases. Based on these results we can postulate that our vaccine is effective for prevention of tumor development. The achieved protection can be augmented with serial vaccinations and can be maintained for a longer period of time.  相似文献   
112.
A bidirectional common polarization control method with a single polarization controller for a coherent optical FDM bidirectional transmission system is discussed. This method is promising for realizing a reliable and low-cost terminal in a coherent multichannel distribution system because the polarization controller can be placed in common only at a central office. Theoretical and experimental results show that the frequency separation δf has to be 6×bit rate<δf<120/Δτ (GHz) for FSK bidirectional transmission. The method is effective not only for reducing the complexity of the subscriber terminal but also for improving the reliability in a coherent CATV system  相似文献   
113.
To determine whether plasma levels of total bile acids may provide a useful index for hypergalactosaemia due to porto-systemic shunts, these levels were determined in hypergalactosaemic neonates. Increased levels were found in all cases with portohepatic venous or portocaval shunts. The levels of both total bile acids and galactose were normalized when the shunts disappeared on the echograms. Both bile acids and galactose are almost completely absorbed by the liver via the first portal blood passage. Portosystemic shunts contribute to elevated levels of bile acids and galactose. CONCLUSION: Increased plasma levels of total bile acids serve as a diagnostic clue to the presence of portosystemic shunts in neonates with hypergalactosaemia.  相似文献   
114.
Type IV collagen, the major component of basement membrane, consists primarily of alpha 1(IV) and alpha 2(IV) chains. Recently, other types of collagen IV chains, i.e. alpha 3(IV), alpha 4(IV), alpha 5(IV) and alpha 6(IV) chains, have been identified by protein chemistry and molecular cloning. We have examined the diversity of the assembly of alpha (IV) chains of the basement membrane surrounding tumour nests of basal cell carcinomas, in tissues from 11 patients, by immunohistochemical analysis using specific monoclonal antibodies to six alpha (IV) chain. The immunostaining profile of each chain differed with respect to the histological subtypes of basal cell carcinoma. In the morphea-like subtype, which was more invasive, alpha 1(IV) and alpha 2(IV) chains were discontinuously stained, and alpha 5(IV) and alpha 6(IV) chains were entirely absent. However, in the superficial subtype, which was non-aggressive, alpha 1(IV), alpha 2(IV), alpha 5(IV) and alpha 6(IV) chains were well stained compared with the other subtypes of basal cell carcinoma. In addition, in the solid subtype, which showed slow growth and ulceration, alpha 1(IV) and alpha 2(IV) chains were continuously stained, and alpha 5(IV) and alpha 6(IV) chains were discontinuous or absent. The assembly of alpha 5(IV) and alpha 6(IV) chains into the basement membrane was inhibited in the solid and morphea subtypes of BCC. This differential expression of type IV collagen chains seems to be associated with the invasive potential of basal cell carcinoma.  相似文献   
115.
The effects of electrolyte pH and temperature on the structure and properties of anodic oxide films formed on niobium in phosphoric acid solution with the addition of NH4OH for pH adjustment have been investigated. The film thickness formed at the same voltage slightly increased with increasing pH and significantly increased with increasing electrolyte temperature. The capacitance of the film was independent of electrolyte pH in an acid region, while it notably increased with increasing pH in an alkaline region. The relative permittivity of the film changed 43.7-80.5 when the electrolyte pH was increased from 1.6 to 10. The incorporation depth and content of phosphorus in the film were markedly suppressed at pH 10, and nitrogen was found to penetrate into a depth of 70%. Furthermore, the apparent transport number of Nb5+ ion decreased from 0.26 to 0.02 by a pH increase from 1.6 to 10. The notable changes in structure and dielectric properties of the anodic niobia film formed in the alkaline region would primarily be caused by the different incorporation behavior of electrolyte species such as phosphorous and nitrogen.  相似文献   
116.
The charcoal-cefazolin-sodium deoxycholate agar (CCDA) was compared with Butzler agar for selectivity of campylobacters from fecal samples. A total of 279 samples of cecal contents from 176 cattle and 103 pigs slaughtered in Saitama were examined. Fifty-five (31.3%) cattle were found to contain campylobacters by the direct plating culture on CCDA plates, compared with 29 (16.5%) on Butzler agar plates. The positive rates of pig samples on CCDA and Butzler agar were very high, being 96 (93.2%) and 86 (83.5%), respectively. After enrichment culture of 107 cattle specimens in Preston, CEM or Bu 10 broth, the isolation rate on CCDA was also higher (p < 0.01) than that on Butzler agar after enrichment in any medium. These results indicate that CCDA medium is easy to handle without blood and, as to this study shows, is superior to Butzler agar for isolation of Campylobacter species from fecal samples.  相似文献   
117.
Histochemical studies of mammary gland sections obtained from healthy lactating Prim' Holstein cows contained numerous corpora amylacea, mainly located in active alveoli. Observations by electron microscopy revealed a cauliflower shape, with a fibrillar or multilayered organization. Mineral studies confirmed the presence of high calcium levels (12.3% of dry matter) and phosphorus (7.4%) in the corpora amylacea composition. These bodies stained positive to Von Kossa silver nitrate and to Periodic acid-Schiff. However, depending on the gland of origin, corpora amylacea stained positive or negative to Congo red. Histochemical studies seemed, therefore, insufficient to determine the presence or absence of amyloid. The amount of total protein varied by approximately 25%. Immunoblotting and analysis of the amino acid sequence of a peptidic fragment obtained from corpora amylacea gave clear evidence of the occurrence of caseins, beta-lactoglobulin and alpha-lactalbumin. However, the comparison between the amino acid composition of corpora amylacea and those of the main milk proteins indicated the presence of other proteins. Electrophoretic analysis also gave evidence of the presence of several other proteins, i.e. glycoproteins. Therefore, it is probable that corpora amylacea composition is much more complex than previously reported.  相似文献   
118.
Cepharanthine is a biscoclaurine alkaloid isolated from Stephania cepharantha Hayata and has been shown to have antiinflammatory, antiallergic, and immunomodulatory activities in vivo. As several inflammatory cytokines and oxidative stresses are involved in the pathogenesis of HIV-1 infection, we investigated the inhibitory effects of cepharanthine on tumor necrosis factor alpha (TNF-alpha)- and phorbol 12-myristate 13-acetate (PMA)-induced HIV-1 replication in chronically infected cell lines. Two chronically HIV-1-infected cell lines, U1 (monocytic) and ACH-2 (T lymphocytic), were stimulated with TNF-alpha or PMA and cultured in the presence of various concentrations of the compound. HIV-1 replication was determined by p24 antigen level. The inhibitory effects of cepharanthine on HIV-1 long terminal repeat (LTR)-driven gene expression and nuclear factor kappaB (NF-kappaB) activation were also examined. Cepharanthine dose dependently inhibited HIV-1 replication in TNF-alpha- and PMA-stimulated U1 cells but not in ACH-2 cells. Its 50% effective and cytotoxic concentrations were 0.016 and 2.2 microg/ml in PMA-stimulated U1 cells, respectively. Cepharanthine was found to suppress HIV-1 LTR-driven gene expression through the inhibition of NF-kappaB activation. These results indicate that cepharanthine is a highly potent inhibitor of HIV-1 replication in a chronically infected monocytic cell line. Since biscoclaurine alkaloids, containing cepharanthine as a major component, are widely used for the treatment of patients with various inflammatory diseases in Japan, cepharanthine should be further pursued for its chemotherapeutic potential in HIV-1-infected patients.  相似文献   
119.
120.
Atherogenic effect of oxidized products of cholesterol   总被引:4,自引:0,他引:4  
Cholesterol under certain in vitro and possibly in vivo conditions may be oxidized to oxysterols, which are suspected of being initiators of atherosclerotic plaques. Oxysterols inhibit HMG-CoA reductase activity resulting in a decreased cholesterol concentration in the cell membrane, which leads to endothelial membrane injury and probable premature cell death. Exogenous oxidation of cholesterol in human tissues under certain unusual conditions is highly probable. Dietary oxysterols are absorbed in the gastrointestinal tract and are selectively transported by the athrogenic lipoproteins LDL and VLDL. The oxysterols cholestanetriol and 25-OH cholesterol have been shown to be atherogenic. Oxysterols are commonly found in dried egg products, powdered milk, cheeses and in a variety of high temperature dried animal products.  相似文献   
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