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121.
The contribution of insulin (3.6 pmol.kg body mass-1.min-1) to adrenaline-induced (0.164 nmol.kg fat free mass-1.min-1) thermogenesis was studied in ten postabsorptive healthy volunteers using two sequential protocols. Variables considered were oxygen consumption as well as carbon dioxide production, heart rate, blood pressure, plasma concentrations of glucose, insulin, glycerol, free fatty acids, beta-HO-butyrate and lactate. Adrenaline increased plasma concentrations of glucose, glycerol, free fatty acids, and beta-HO-butyrate, and heart rate and metabolic rate during normo-insulinaemia [61.3 (SEM 6.6) pmol.l-1]. Similar effects were observed during hyperinsulinaemia [167.9 (SEM 18.7) pmol.l-1], but the effect of adrenaline on oxygen consumption was reduced. On average, metabolic rate increased by 12.9% during normo-insulinaemia and by 8.9% during hyperinsulinaemia. We concluded that relative hyperinsulinaemia resulted in decreased adrenaline-induced thermogenesis and therefore increased whole body anabolism.  相似文献   
122.
Summary DBA/2 (H-2d) mice bearing a transplanted highly metastatic lymphoma (ESb) in a state of widely disseminated disease could be successfully treated by a combination of surgery (removal of the local tumour), irradiation (5 Gy) and adoptive immunotherapy. The immunotherapy was achieved by transfer of anti-ESb-immune spleen cells from B10.D2 mice, which express the same major histocompatibility complex (MHC) molecules as DBA/2. In contrast, anti-ESb-immune cells from MHC-disparate C57BL/6 mice did not confer protective immunity. The B10.D2 anti-ESb-immune T cells contain two types of cytolytic specificity as detected by limiting-dilution analysis: (1) clones with specificity for the ESb-tumour-associated transplantation antigen (TATA) (at low frequency), and (b) clones with specificity for minor DBA/2 histocompatibility (H) antigens (at high frequency). Immune B10.D2 cells raised against different tumour lines or against TATA ESb tumour variants did not confer the 100% protection seen with immune cells against ESb TATA+ cells. Finally we demonstrate that the allogeneic immune cells are more potent in terms of protective immunity than corresponding syngeneic immune cells. The data suggest that the strong graft-versus-leukemia effect with immune T cells from allogeneic MHC-identical but not from MHC-disparate mice was due to T cells with MHC-restricted specificity for an ESb-associated TATA. A graft-versus-host reactivity that developed much later and could not be prevented was most likely due to T cells sensitized against normal minor H antigens of the host. Our results are of potential relevance for allogeneic bone marrow transplantation and adoptive immunotherapy protocols.  相似文献   
123.
Plasmolipin is a plasma membrane proteolipid is a major myelin membrane component (Cochary et al., 1990). In this study we report the phylogenic expression of plasmolipin in the vertebrate nervous system. Using Western blot analysis with polyclonal antibodies, we have analyzed membrane fractions, including myelin, from elasmobranchs, teleosts, amphibians, reptiles, birds and mammals. On the basis of immune detection, plasmolipin appears to be restricted to the mammalian nervous system. Comparison of the central and peripheral nervous systems of mammals showed only minor differences in the level of plasmolipin in these two regions. Within mammals, little quantitative differences were observed when rat, human and bovine membrane fractions were compared. The late evolutionary expression of plasmolipin which results in its restriction to mammals makes it unique among the (major) myelin proteins. The potential physiologic significance of these data are discussed.Abbreviations EDTA Ethylene diamine N.,NN tetracetic acid - EGTA Ethylene glycol bis-(B-Aminoethyl Ether) N,,NN tetracetic acid - MES ([N-Morpholino] ethane sulfonic acid) DCCD, N, Dicyclohexyl carbodiimide  相似文献   
124.
The results of genome analysis of five hybrids, viz.Elymus patagonicus ×Hordeum procerum, E. patagonicus ×H. tetraploidum, E. angulatus ×H. jubatum, E. angulatus ×H. lechleri, andE. angulatus ×H. parodii, are reported. The genomic constitution ofHordeum tetraploidum andH. jubatum is best given as H1H1H2H2, ofH. lechleri andH. parodii as H1H1H2H2H4H4, ofH. procerum as H1H1H2H2H3H3, and ofElymus patagonicus andE. angulatus as SSH1H1H2H2.  相似文献   
125.
In 17 malignant peritoneal effusions due to papillary serous adenocarcinoma of the ovary, the reaction patterns of the tumor cells to monoclonal antibodies (MAbs) against surface antigens were studied and compared with the reaction patterns of mesothelial cells in the same effusions. The following surface markers were used with the adhesive slide method: epithelial membrane antigen (EMA), human epithelium-specific cell surface antigen (HEA-125), human endothelial antigen (BMA-120), carcinoembryonic antigen (CEA 3-13), an antibody against natural killer cells and cytotoxic cells (BMA-070), granulocyte antigen (Leu M1) and leukocyte antigen of class I (HLA-1). In all cases, from 30% to 95% of the tumor cells reacted with EMA and HEA-125. Tumor cells showed a positive staining with CEA 3-13 in only five cases. In all cases, from 75% to 95% of the tumor cells reacted positively with BMA-120. The reactivity of a few mesothelial cells with EMA and of all mesothelial cells with BMA-120 did not interfere with the identification of positive tumor cells since the reaction patterns were different. Interestingly, our study demonstrated that BMA-070, an MAb identifying natural killer cells and cytotoxic cells, is also a most useful tumor marker. The same was found to be true for Leu M1, an MAb originally thought to react only with granulocytes. The tumor cells showed a partial or total loss of the expression of HLA-1 reactivity. Since all cases were immunocytochemically positive for tumor cells while conventional cytology was positive in only 13 of the cases, the immunocytochemical analysis of malignant peritoneal effusions due to papillary serous adenocarcinoma of the ovary seems able to improve the cytologic diagnosis of the fluids.  相似文献   
126.
Atresia of the right atrial ostium of the coronary sinus   总被引:1,自引:0,他引:1  
A case of asymptomatic congenital occlusion of the ostium of the coronary sinus is described. The myocardial venous drainage was maintained via a persistent left superior vena cava as well via ectatic, widened atrial veins of the dorsal wall of the left atrium. The study shows that complete ostial occlusion of the coronary sinus does not reduce cardiac venous drainage. The view of the literature allows a comparison with the comprehensive classification of coronary sinus anomalies.  相似文献   
127.
The role played by cell addition, cell enlargement, and matrix deposition in the endochondral growth of the condyle was assessed in weanling rats by four approaches making use of the light microscope: morphometry, 3H-thymidine radioautography, 3H-proline radioautography, and immunostaining for the cartilage-specific type II collagen. From the articular surface down, the condyle may be divided into five layers made up of cells embedded in a matrix: 1) the articular layer composed of static cells in a matrix rich in fibers presumed to be of type I collagen, 2) the polymorphic cell layer including the progenitor cells from which arise the cells undergoing endochondral changes, 3) the flattened cell layer in which cells produce a precartilagenous matrix devoid of type II collagen while undergoing differentiation in two stages: a "chondroblast" stage and a short "flattened chondrocyte" stage when intracellular type II collagen elaboration begins, 4) the upper hypertrophic cell layer, in which cells are "typical chondrocytes" that enlarge at a rapid rate, actively produce type II collagen, and deposit it into a cartilagenous matrix, and 5) the lower hypertrophic cell layer, composed of chondrocytes at a stage of terminal enlargement while the cartilagenous matrix is adapting for mineralization. 3H-thymidine radioautographic results indicate that the turnover time of progenitor cells in the polymorphic cell layer is about 2.9 days. The time spent by cells at each stage of development is estimated to be 1.4 days as chondroblasts, 0.5 days as flattened chondrocytes, 2.3 days as the chondrocytes of the upper hypertrophic cell layer, and 1.1 days as those of the lower hypertrophic cell layer. Calculations referring to a 1 x 1-mm square-sided column extending from the articular surface to the zone of vascular invasion provide the daily rate of cell addition (0.0077 mm3), extracellular matrix deposition (0.0127 mm3), and cell enlargement (0.0302 mm3). Hence the respective contribution of the three factors to condyle growth is in a ratio of about 1:1.6:4. This result emphasizes the role played by cell enlargement in the overall growth of the condyle.  相似文献   
128.
129.
Stigmatellin and its derivatives represent a third class of Qo site inhibitors besides the hydroxyquinone derivatives and the E-beta-methoxyacrylate (MOA) inhibitors [von Jagow and Link (1986) Methods Enzymol. 126, 253-271]. The stigmatellins consist of a chromone ring system connected to an substituted alkenyl side chain. Alterations in the side chain, i.e. saturation of the C = C double bonds, shift of a methoxy group or loss of the methyl groups, specifically affect the binding characteristics. Besides changing the red shift spectrum of reduced cytochrome b566 and the EPR spectrum of the Rieske iron-sulfur cluster, the side chain alterations diminish the binding affinity and the extent of the midpoint potential shift of the iron-sulfur protein. Thus, the side chain of the molecule makes an essential contribution to the binding energy and is not necessary solely for partitioning the molecule into the hydrophobic phase, as assumed so far.  相似文献   
130.
Prospective experimental field evaluation of genetically engineered microorganisms, such as microbial pest control agents, raises issues of how to properly ascertain their fate and survival in the environment. Field trials with recombinant organisms must reflect requirements for sampling and monitoring. Field trials were conducted at Tulelake, Calif., to monitor the numbers of viable cells of a nonrecombinant strain of Pseudomonas syringae that entered the atmosphere and landed on plants and soil during and after an aerosol spray application. An exponential decrease in numbers of viable cells deposited at increasing distances from three sprayed plots was observed. The relative rate of survival of cells sprayed directly on plants was more than 10 times higher than that of cells dispersed through the air to similar adjacent plants. Results are being used to gain experience with the characteristics of a release site that influence containment or dispersal and to develop appropriate sampling methodologies for evaluating survival and dispersal characteristics of genetically engineered bacteria released into the environment. The ability to make predictions about microbial dispersal and survival will reduce the uncertainties associated with environmental releases of recombinant organisms.  相似文献   
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