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201.
In order to confirm the presence of an acrophase difference based upon genotype in the seasonal expression of an immune competence end point, splenic plaque-forming cell (PFC) response to sheep red blood cells (SRBC), female B6C3F1 and CD1 mice were concurrently studied for PFC response during two studies performed in each season for 1 year. Mice were multiply housed, fed ad libitum, and standardized to light (06:00-18:00); dark (18:00-06:00). For each strain and study, subgroups were either naive (n = 10), received a vehicle (n = 10) or Cytoxan (n = 5). Challenge with SRBC occurred in early afternoon 4 days before harvesting of spleens and PFC assay. All other procedures were performed early in the daily light span. Analysis of variance and single cosinor analysis revealed a significant seasonal time effect for PFC in naive mice of both strains. Antibody formation was greatest in spring for CD1 mice and in summer for the B6C3F1 mice. These acrophases were consistent with earlier results for both strains and show the phenomena to be reproducible and genetically based.  相似文献   
202.
There are two H+-pumping enzymes at the tonoplast membrane of plant vacuoles, the V-ATPase and the V-PPase. One attempt to explain the enigma of “two H+ pumps, one membrane” was the suggestion that the V-PPase has special functions in young developing and growing tissues in utilization of pyrophosphate produced in particularly active metabolism and in pumping of K+ for vacuolization. This should lead to reciprocal expression of both enzymes with time during development. Here we used stimulation of Kalanchoë blossfeldiana Poellnitz cv. Tom Thumb plants by short-day treatments to induce crassulacean acid metabolism and flowering and of Ricinus communis L. stem tissue by infection with Agrobacterium tumefaciens strain C58 to induce vigorous growth of tumours, and we compared these stimulated tissues with leaves of non-stimulated long-day controls and non-infected stem tissue, respectively. Activities and protein levels of both enzymes increased (K. blossfeldiana) or remained high (R. communis) in the stimulated tissues and decreased in the non-stimulated tissues with time. Time-dependent patterns of the two enzymes were concordant in all of the four cases and not inverse, i.e. two plants with two different conditions each, leading to very different developmental situations.  相似文献   
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In the time period from November 1984 to January 1987 eight allogeneic bone marrow transplantation were performed from HLA-identical siblings. The theoretical chance of success in this group was between 21 and 50%, according to the recent data of the International Bone Marrow Transplant Registry, depending on the diagnosis and clinical condition. The average chance was 37.5%. Haemopoietic reconstitution was achieved in 6 recipients, while 2 died of early complications (cytostatic induced hepatocellular damage and fungal sepsis). Another 3 patients died of complications of the intermediate period (pulmonary bleeding, virus hepatitis, graft rejection). The remaining 3 recipients are alive, in excellent clinical condition, including one girl surviving more than 2 years after the transplantation.  相似文献   
208.
A low concentration estrogen-derivatized affinity resin has been used in a rapid, single step purification of the untransformed estrogen receptor from calf uterine cytosols prepared without sodium molybdata. The procedure isolates the Mr 65,000 estrogen receptor in association with the bovine heat shock protein hsp90. Small amounts of proteolyzed receptor ranging in size from Mr 50,000 to 60,000 are also present in the purified extracts. Results from affinity chromatography of receptor cytosols either untreated or presaturated with estradiol suggest that two proteins of Mr 22,000 and 38,000 are co-purified with the untransformed receptor complex and may represent additional nonhormone-binding components of the native receptor form. Some indication of the stability of protein-protein interactions within the oligomeric complex has been derived from differential salt elution studies with heparin-sepharose and affinity gel-immobilized untransformed receptor. On size exclusion high performance liquid chromatography the untransformed complex eluted with a Stokes radius of 75 +/- 2 A (n = 18), but was shown to be sensitive to extended ultracentrifugal analysis dissociating to the receptor homodimer, sedimentation coefficient 5.3 +/- 0.3 s (n = 5). Preliminary data on urea- and heat-induced transformation of the isolated receptor to the DNA-binding state is presented.  相似文献   
209.
Changes serum electrolytes in patients with allogenic bone marrow transplants have been analyzed. A decrease in serum potassium and calcium with slight increase in serum phosphorus concentration were noted in all patients, who were given busulphan and cyclophosphamide prior to bone marrow transplantation. All patients, in whom a hematological reconstitution was achieved, were released from the hospital with normal serum electrolyte concentration. Significant electrolyte disorders were seen in patients in whom hematopoiesis was not achieved or fatal complications occurred.  相似文献   
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