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Journal of Digital Imaging - Vertebral Compression Fracture (VCF) occurs when the vertebral body partially collapses under the action of compressive forces. Non-traumatic VCFs can be secondary to...  相似文献   
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The anti-granulocyte activity of serum from patients with B-cell chronic lymphocytic leukaemia (CLL) and other lymphoproliferative disorders was investigated. Granulocyte-binding IgG was measured in 34 patients with CLL, 13 patients with hairy cell leukaemia, one patient with prolymphocytic leukaemia, two patients with Sézary cell leukaemia, and seven patients with chronic T-cell lymphocytosis who had a predominance of circulating large granular lymphocytes. Anti-granulocyte activity was absent in CLL and its variants, but present in the majority of granulocytopenic patients with chronic T-cell lymphocytosis. In one of these patients, granulocytopenia was associated with complement-activating IgG granulocyte antibody. Thus, antibody-mediated granulocyte injury appears to be an unusual occurrence in chronic lymphocytic leukaemia, but is a frequent complication of chronic T-cell lymphocytosis.  相似文献   
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The melt agglomeration process of lactose powder with hydrogenated cottonseed oil (HCO) as the hydrophobic meltable binder was investigated by studying the physicochemical properties of molten HCO modified by sucrose stearates S170, S770 and S1570. The size, size distribution, micromeritic and adhesion properties of agglomerates as well as surface tension, contact angle, viscosity and specific volume of molten HCO, with and without sucrose stearates, were examined. The viscosity, specific volume and surface tension of molten HCO were found to be modified to varying extents by sucrose stearates which are available in different HLB values and melt properties. The growth of melt agglomerates was promoted predominantly by an increase in viscosity, an increase in specific volume or a decrease in surface tension of the molten binding liquid. The agglomerate growth propensity was higher with an increase in inter-particulate binding strength, agglomerate surface wetness and extent of agglomerate consolidation which enhanced the liquid migration from agglomerate core to periphery leading to an increased surface plasticity for coalescence. The inclusion of high concentrations of completely meltable sucrose stearate S170 greatly induced the growth of agglomerates through increased specific volume and viscosity of the molten binding liquid. On the other hand, the inclusion of incompletely meltable sucrose stearates S770 and S1570 promoted the agglomeration mainly via the reduction in surface tension of the molten binding liquid with declining agglomerate growth propensity at high sucrose stearate concentrations. In addition to being an agglomeration modifier, sucrose stearate demonstrated anti-adherent property in melt agglomeration process. The properties of molten HCO and melt agglomerates were dependent on the type and concentration of sucrose stearate added.  相似文献   
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We reviewed randomised clinical trials evaluating the effect of lymphoblastoid or recombinant alpha-interferon in non-A, non-B chronic hepatitis. The outcomes assessed were the rates of serum alanine aminotransferase normalization and relapse during and after stopping interferon. Data were pooled by meta-analysis and a 50% overall rate difference, favouring treated patients, was found. Results showed homogeneity in direction of treatment effect both after short-term (2-6 months, greater than or equal to 2 mega-units thrice weekly) and long-term (9-18 months, variable dose) interferon course. Moreover, results did not change when type of publication (abstracts vs. full reports) and treatment duration or schedule were accounted for. About 50% of patients originally responding to treatment relapsed within 6 months of either dose reduction or stopping interferon, thus suggesting that only in about one out of four patients is benefit from treatment sustained up to 1 year. We conclude that larger trials are needed to identify an optimal schedule of treatment and to evaluate predictors of interferon effectiveness in patients with non-A, non-B chronic hepatitis.  相似文献   
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The activation of membrane-associated phospholipase C is rapidly and transiently induced in the central nervous system by a variety of stimuli. Ischaemic brain injury is one of the situations that leads to a dramatic increase in polyphosphoinositide (PPI) turnover. In this study, stimulation of PPI hydrolysis by glutamate (500 μM) was measured in hippocampal slices from rats up to 21 days after an ischaemic insult of 30 min. Ischaemia was induced using the four-vessel occlusion method. PPI hydrolysis elicited by glutamate was significantly increased in the slices prepared from ischaemic rats 24 h after reperfusion, the accumulation of inositol phosphates (InsPs) and inositol 1,4,5-trisphosphate (InsP3) was 614±74% ( n = 8) and 182±11% ( n = 9) of the basal level respectively. This potentiation was also observed 21 days after ischaemia. Hyper-responsiveness to glutamate was also accompanied by an increase in AIF4-stimulated formation of [3H]inositol phosphates. In addition, global ischaemia did not change either high-affinity [3H]glutamate binding in hippocampal membranes or the stimulation of PPI hydrolysis by carbachol or noradrenaline in hippocampal slices. The present results suggest that the increased responsiveness to glutamate is the result, at least in part, of functional changes at the G-protein level, and may contribute to the pathophysiology of ischaemic brain injury or to the regenerative phenomena that accompany ischaemic damage.  相似文献   
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Invasive aspergillosis is a serious complication in immunocompromised patients. The effects of recombinant human tumor necrosis factor alpha (TNF-α) on antifungal activities of human neutrophils (polymorphonuclear leukocytes [PMNs]), human monocytes (MNCs), and rabbit pulmonary alveolar macrophages (PAMs) against Aspergillus fumigatus were studied. The percentage of PMN-induced hyphal damage was increased after 30 min of incubation of PMNs with 0.1 ng of TNF-α per ml at 37°C (P = 0.043). At 0.1 to 10 ng/ml, TNF-α also increased superoxide anion (O2) produced by PMNs in response to phorbol myristate acetate, N-formylmethionyl leucyl phenylalanine, and unopsonized hyphae (P < 0.01) but did not exert any effect on PMN phagocytosis of conidia in the presence of serum. By comparison, TNF-α induced only a slight increase in O2 production by MNCs in response to phorbol myristate acetate (P = 0.05) and no concomitant increase in the percentage of MNC-induced hyphal damage. Incubation of MNCs with TNF-α at 0.001 to 10 ng/ml for 2 days had no effect on phagocytosis or conidiocidal activity. By contrast, incubation of PAMs with TNF-α at 0.1 to 10 ng/ml for 2 days increased phagocytosis of conidia (P = 0.03). Thus, TNF-α augments the capacity of PMNs to damage Aspergillus hyphae, possibly through enhanced oxidative mechanisms, and increases PAM phagocytic activity against conidia. As such, TNF-α may have an important role in host defense against aspergillosis, and neutralization of its activity may be complicated by increased susceptibility to aspergillosis.  相似文献   
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Tin Han  Barbara Dadey    Jun Minowada 《Immunology》1977,33(4):543-551
Fresh normal peripheral blood B lymphocytes possess a strong stimulating capacity while fresh thymus cells or fresh peripheral T lymphocytes possess a weak, but significant stimulating capacity on allogeneic lymphocytes in `one-way' mixed lymphocyte reaction. Fresh leukaemic T lymphoid cells from patients with T-cell ALL or T-cell CLL exert little or no stimulation on allogeneic lymphocytes. Fresh leukaemic B lymphoid cells from patients with B-cell CLL or B-cell HCL, on the other hand, exert a lesser stimulation on allogeneic lymphocytes, as compared to that of normal B lymphocytes. Leukaemic myeloblasts from patients with AML or Ph1(+) CML-BP exert significantly higher stimulation than leukaemic lymphoid cells in `one-way' mixed lymphocyte reaction (P<0.05). Cultured leukaemic T lymphoid cells (MOLT-4) possess no stimulating capacity, cultured leukaemic B lymphoid cells (BALM-2) possess a moderate degree of stimulating capacity and cultured leukaemic, possibly myeloid, cells (NALM-1 and K562) possess vigorous stimulation on allogeneic lymphocytes. The stimulating capacity of NALM-1 or K562 cells is significantly higher than that of BALM-2 cells (P<0.01 or P<0.05, respectively) and that of MOLT-4 cells (P<0.001). These observations suggest that the stimulating capacity of leukaemic T or B lymphoid cells may have been completely or partially lost during the process of leukaemogenesis. Since we do not have an opportunity to study the stimulating capacity of normal myeloblasts, it is not known whether the stimulating capacity of leukaemic myeloblasts, which is found to be very strong on allogeneic lymphocytes, may have been modified during the process of leukaemogenesis.  相似文献   
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