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31.
The results of a randomised trial of polyadenylic-polyuridylic acid given as adjuvant treatment for operable breast cancer were reviewed after a mean follow up period of 87 months. Of the 300 patients included in the original trial, 145 had been allocated to conventional treatment alone and served as controls. At the time of review the overall survival of the group given polyadenylic-polyuridylic acid was significantly improved (p less than 0.05) as compared with that of the controls given conventional treatment alone. Significant benefit (p less than 0.02) was also observed among patients with evidence of disease in lymph nodes, the best results occurring in those with up to three invaded nodes, who showed a significant increase in both overall and relapse free survival. No evidence of toxicity was recorded. These findings confirm the value of polyadenylic-polyuridylic acid as adjuvant treatment for operable breast cancer. Results in an experimental model and in patients receiving the adjuvant suggested a possible role of interferon and natural killer (NK) cells in the mechanism of action.  相似文献   
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Viruses above about 60 nm in diameter may be rapidly sized to a few nanometers in their natural hydrated state as they pass one by one through a single pore in a newly developed nanometer-particle analyzer based on the resistive-pulse technique of the Coulter Counter and the use of submicron diameter pores made by the Nuclepore process. Size measurements for several type C oncornaviruses are: Rauscher murine leukemia, 122.3 +/- 2 nm; simian sarcoma, 109.7 +/- 3 nm; Mason-Pfizer monkey, 140.0 +/- 2.5 nm; RD-114, 115 +/- 5 nm; and feline leukemia, 127.4 +/- 2 nm, relative to standard 109-nm latex spheres. The T2 bacteriophage has a volume of (5.10 +/- 0.15) X 10(-16) cm3. Concentrations of viruses near 10(9) to 10(11)/ml that are fairly clear of debris are routinely measurable in a few minutes to an accuracy near 15%. A lower practical count limit is near 5 X 10(7) viruses per ml.  相似文献   
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A new property of ursolic acid, lipoxygenase and cyclooxygenase inhibition, has been described in an acetone-extract of heather flowers (Calluna vulgaris) which could help explain the anti-inflammatory characteristics of this plant. In mouse peritoneal macrophages, human platelets and differentiated HL60 leukemic cells, ursolic acid, at 1 microM, blocks arachidonate metabolism.  相似文献   
34.
We report that a gene responsible for familial hypertrophic cardiomyopathy (HC) is closely linked to the cardiac alpha and beta myosin heavy chain (MHC) genes on chromosome 14q11. We have recently shown that probe CRI-L436, derived from the anonymous DNA locus D14S26, detects a polymorphic restriction fragment that segregates with familial HC in affected members of a large Canadian family. Using chromosomal in situ hybridization, we have mapped CRI-L436 to chromosome 14 at q11-q12. Because the cardiac MHC genes also map to this chromosomal band, we have determined the genetic distances between the cardiac beta MHC gene, D14S26, and the familial HC locus. Data presented here show that these three loci are linked within 5 centimorgans on chromosome 14 at q11-q12. The possibility that defects in either the cardiac alpha or beta MHC genes are responsible for familial HC is discussed.  相似文献   
35.
Summary Recently techniques have been developed for the long-term growth of cytotoxic T-lymphoid cells in vitro with T cell growth factor (TCGF). We have investigated the use of these in vitro-expanded T cells for the immunotherapy of a disseminated syngeneic murine FBL-3 lymphoma. In this model, mice with disseminated tumor were treated on day 5 with 180 mg cytoxan/kg and then 5 h later were given lymphoid cells IP. In vivo-immunized lymphocytes resulted in significantly improved survival in three of three experiments, curing 52% of 38 animals, compared with treatment with cytoxan alone (0 of 31 cured) or cytoxan plus unimmunized cells (0 of 40 cured) (P<0.0005). In vivo-immunized lymphocytes were re-exposed to FBL-3 tumor in vitro for 5 days in complete medium (CM) or lectin-free TCGF (LF-TCGF). Both groups showed significantly improved survival in six of six experiments. Cytoxan cured 17% of 66 animals, while cytoxan plus normal lymphocytes after IVS cured 6% of 47 animals. In vivo-immunized cells resensitized in vitro to FBL-3 in CM or LF-TCGF cured 82% of 50 animals (P<0.001) and 72% of 61 animals (P<0.001), respectively. Cells from in vivo- and in vitro-sensitized lymphocytes exhibited no cytotoxicity in our in vitro 51Cr-release assay; expansion of these cells resulted in significant specific lysis of fresh FBL-3 targets. Adoptive transfer of immune lymphocytes resensitized to FBL-3 tumor in vitro and expanded in LF-TCGF conferred a significant survival benefit (P<0.001, curing 7 of 27 animals) compared with all controls. These expanded cells were then continuously grown in LF-TCGF for 2 1/2 months. Again, in vivo-immunized lymphocytes resensitized to FBL-3 tumor and expanded in LF-TCGF for 2 1/2 months cured 56% of the animals with disseminated tumor, significantly prolonging survival over that recorded in any control group (P<0.0002). Irradiation of these same cells totally abolished their efficacy. Clones were generated from IVS and continuously grown in LF-TCGF. Two of these clones were very cytotoxic for fresh FBL-3 (>4,000 lytic units/106 cells). When adoptively transferred to mice in this chemoimmunotherapy model these cytotoxic clones significantly enhanced survival over that recorded following treatment with cytoxan alone (P<0.00001), though prolongation of survival was small. Implications of these results for application of these techniques to other less antigenic tumors and human cancers are discussed.  相似文献   
36.
The role of H-2 in T cell recognition of Mls   总被引:2,自引:0,他引:2  
The role of H-2 was evaluated in T cell recognition of Mls-encoded antigens during primary mixed lymphocyte responses (MLR). Mlsc was used as a stimulating determinant in MLR and its recognition by T cells was assessed by linear regression analysis under culture conditions in which (A x B)F1 responder cell number was the factor limiting total response. Results of such experiments indicated the presence of distinct (A x B)F1 responder T cell subpopulations capable of differentially recognizing the foreign Mls antigen in association with one or the other parental H-2 haplotype. These findings demonstrate that T cells do not recognize Mlsc products in isolation, but rather are restricted to recognition of Mlsc in the context of "self" H-2 determinants.  相似文献   
37.
Preliminary studies using an improved method for the agarose gel electrophoresis of semipurified, cleared lysates of staphylococci have indicated some distinct differences in plasmid composition between the coagulase-positive speciesStaphylococcus aureus andStaphylococcus intermedius, and various coagulase-negative species. Penicillinase-positive strains ofS. intermedius andS. simulans did not carry large penicillinase plasmids like most penicillinase-positive strains ofS. aureus. Most coagulase-negative species examined demonstrated complex plasmid profiles. Codigestion by the restriction endonucleasesHaeIII andHpaI offered a useful approach for “fingerprinting” large plasmids from various strains and species.  相似文献   
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