The elongation and subsequent relaxation of dilute polyisobutylene solutions in mixtures of polybutene and kerosine and in mixtures of polybutene and toluene have been investigated using an ...extensional rheometer based on the principle of droplet stretching. Single exponential stretching functions have been applied and the resulting non-idealities of the experiment will be addressed. The results show that the transient Trouton ratio for different values of the applied axial extension rate between 1 and 6 s
−1 scales with the strain for values larger than 3. The magnitude of non-ideal stretching effects on the Trouton ratio for strain values up to 3 is found to be fairly small. For strains larger than 5.5 the onset of steady-state values of the extensional viscosity is found, but true steady-state values are not obtained below the maximum strain of 7.2. The measurements provide an indication for increasing plateau values with increasing concentration and with increasing molecular weight of the polymer. The results also show that the relaxation after stretching up to a specific axial strain value with different extension rates scales with the product of the extension rate at the start of the relaxation process and the time.
To determine the maturation arrest of the neoplastic cells of hairy-cell leukemia (HCL) and the spectrum of the surface markers on these cells, a series of 51 patients with this disease was studied. ...The cells of all but two of the patients showed monoclonal surface Ig with respect to light chains. In about one-third of the cases, only γ heavy chain determinants were present on the cells; the majority carried multiple heavy chain determinants as documented by the application of different fluorochromes. Two patients each showed two different clones of cells, both of the same light chain type. In one of these two patients, two paraproteins were present in the serum. Intracyto-plasmic Ig was found in only 4 of 39 cases, in all instances being IgM. All cases studied concerned cells with FcIgG receptors; however, the density of this receptor varied. FcIgM receptors also showed a spectrum of density, with some cases showing very few FclgM-positive cells. Receptors for C3 were not observed on the hairy cells. Serum immunoglobulin levels were normal or increased. Paraproteins were found in the sera of 4 of 38 patients. These data suggest that HCL is a neoplasm of B lymphocytes. The neoplastic cells are probably arrested at a more mature stage than the cells of chronic lymphocytic leukemia. The multiple isotypes on the cells indicate a block at the “switch” phase from the small μ-carrying lymphocyte to the larger Ig-producing lymphocyte or plasma cell.
We have designed and constructed a new multi-channel radio spectrograph for the study of short-lived structures in solar microwave bursts. It measured the integrated flux over the whole solar disc in ...two circular polarizations at 36 frequencies between 4 and 8 GHz, with a time constant of 0.5 ms. We have analyzed all 119 recorded bursts observed in 1981 and 1983. We focused our attention on events with a lifetime of less than 1 s. Fine structure occurs in about 30% of the observed bursts, and can be as rich in detail as in bursts observed at lower frequencies. We found at least four different classes of events. In one event neither bandwidth nor time resolution of the receiver appear to be sufficient to resolve the fine structure. The bulk of the drifts is found to be towards higher frequencies. Periodic flux variations were found in two cases.
One of the unexplained features of human IgD is its preferential expression with either kappa or lambda light chains in different situations. While the membrane IgD on B lymphocytes shows a ...predominance of the kappa type, about 90% of all known IgD myeloma proteins and 87% of normal IgD producing plasma cells in spleens of healthy individuals were shown to belong to the lambda type. Very little is known of the kappa/lambda light chain distribution of normal polyclonal IgD in the serum and in the bone marrow plasma cells. In this study, the kappa/lambda representation of IgD in bone marrow plasma cells and in the serum of 25 adult persons (two healthy and 23 suffering from various nonmalignant diseases) was investigated. The kappa/lambda ratio of IgD+ bone marrow plasma cells showed a large variation among the individuals of this group, in 84% of the cases being below 1.0. While about 1/3 of the investigated subjects had 80% or more of IgD of the lambda type (kappa/lambda ratio below 0.2), most showed a kappa/lambda ratio of IgD higher than that, with four persons exhibiting a clear cut predominance of IgD of the kappa type. A positive correlation (Spearman's correlation co-efficient, P = 0.005) between the percentages of IgD+ plasma cells and their kappa/lambda ratio was found. Semiquantitative evaluation of the kappa/lambda composition within the serum IgD by immunoselection was in agreement with the kappa/lambda ratio of IgD+ plasma cells in all individual cases.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A retrospective study was initiated to investigate the influence of recipients' Lewis subtype and HLA-matching on cadaveric kidney graft outcome. A total of 1111 patients receiving a first cadaveric ...kidney graft were analyzed. No difference in one-year graft survival was found between Lewis-negative (73%, n = 133) and Lewis-positive (73%, n = 978) recipients. Further subdivision of the study group into HLA-A,-B well-matched (0 or 1 mismatches MM) and poorly matched (2, 3, or 4 MM) revealed a strong deleterious effect of HLA-A,-B mismatching in the Lewis-negative group only. One year graft survival in Lewis-negative HLA-A,-B poorly matched (2, 3, or 4 A,B MM) patients was 60% (n = 67) versus 86% (n = 66) in the Lewis-negative HLA-A,-B well-matched (0 or 1 A,B MM) group (P = 0.004). For the Lewis-positive group the one-year graft survival rates were 72% (2, 3, or 4 A,B MM; n = 498) and 74% (0 or 1 A,B MM; n = 480), respectively (P = n.s.). The additional beneficial effect of HLA-DR matching again turned out to be strongest in the Lewis-negative group. In Lewis-negative, HLA-DR (0 MM) and -A,-B well-matched recipients (n = 36) graft survival was 94% versus only 64% in the Lewis-negative, DR matched, A,-B mismatched (2, 3, or 4 A,B MM) group (n = 25; P = 0.09). In the Lewis-positive, HLA-DR 0 mismatched group the one-year survival rates were 78% (0 or 1 A,B MM; n = 240) and 73% (2, 3, or 4 A,B MM; n = 253), respectively (P = 0.05). Our data suggest that donor recipient selection should not be based on Lewis matching per se. However, since Lewis-negative patients are at high risk of graft failure when receiving HLA mismatched kidneys, they should preferentially receive optimally HLA matched grafts.
In the dynamic spectrograms of the 60-channel solar radiospectrograph at Dwingeloo, coherent groups of type I bursts were selected. At 243 MHz, the positions of the bursts were measured. Within many ...groups, the bursts showed a systematic angular displacement with time. Movements with apparent velocities to 15,000 km sec super(-) super(1) were observed. The burst positions were obtained with a two-element interferometer. A special data reduction method used the amplitude variation of the type I bursts as a parameter for selection against the background radiation.
Most cases of hairy-cell leukaemia (HCL) involve proliferations of neoplastic B lymphocytes. In rare cases, M-proteins or osteolytic lesions have been documented in patients with HCL. In this study ...two patients with typical HCL are reported in whom both paraproteinaemia and osteolytic lesions of the femoral neck developed. In one of the patients the production of the M-protein by hairy cells could be established. In the other patient, at autopsy no signs of myeloma were found. The hairy cells from inside the osteolytic lesion had the same immunological phenotype as hairy cells from the peripheral blood, the spleen, and other parts of the bone marrow. These cases once more confirm the B-cell nature of many cases of HCL, and show that hairy cells can have functional capacities usually attributed to much more mature B lymphocytes, i.e. plasma cells.
A patient with IgA lambda multiple myeloma (MM) developed plasma cell leukemia (PCL), presenting as oculomotor nerve palsy. The cerebrospinal fluid (CSF) contained plasma cells, which double stained ...with fluoresceinated anti‐IgA and anti‐lambda antisera. The palsy was most probably due to meningeal myelomatosis. The neurologic disorder appeared to be refractory to the therapy used, although plasma cells disappeared from the peripheral blood. Secondary plasma cell leukemia is a rare complication of MM, usually occurring in the terminal stage of the disease. Those patients may be eligible for central nervous system (CNS) prophylaxis, as is commonly performed in patients with other types of leukemia.
A case history of a patient with primary plasma cell leukaemia is presented. Analysis of serum showed an IgD lambda paraprotein, and lambda-light-chains were found in the urine. Immunofluorescence ...studies of a bone marrow aspirate revealed intracytoplasmatic IgD of lambda-type in plasma cells. Moreover J-chain could be demonstrated in these plasma cells. A complete remission of the disease, with disappearance of the paraprotein, was obtained following treatment with a combination of cyclophosphamide, vincristine and prednisone. 12 months later, the patient developed multiple extramedullary plasmocytoma lesions in the skin. After treatment with cyclophosphamide, vincristine, doxorubicin and prednisone, another remission was achieved. The literature on the clinical features and the response to chemotherapy of primary plasma cell leukemia is reviewed.
5 sera from a series of more than 1,000 serum samples from hospitalized patients tested by immunoelectrophoresis were selected for further examination because of a disproportional increase in the ...anodic part of IgG. A marked polyclonal increase in IgG4 subclass level was detected in each of these sera. While the patients suffered from a variety of diseases (e.g. Loeffler's syndrome, leiomyosarcoma, periarteritis nodosa, chronic bronchitis, and mycosis fungoides, respectively), they all had an acquired respiratory disease as the only common clinical denominator.
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