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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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目的 探讨血管新生指标CD34、CD31、vWF、Ⅳ型胶原纤维及层粘连蛋白在肝细胞肝癌(HCC)中的表达及意义 ,同时比较上述几种血管新生因子与增殖细胞核抗原 (PCNA)、病理指标及预后的相关性 ,以便筛选出有效的临床预后指标。方法 采用免疫组化方法 ,对 5 3例肝细胞肝癌的标本进行CD31、CD34、vWF、Ⅳ型胶原纤维及层粘连蛋白的染色、计数 ,并用检测数据与患者的临床资料进行统计分析。结果 统计染色的血管面积后发现 ,CD34与多种临床病理指标无相关性 ;CD31与肝内门静脉浸润相关 ;vWF与肿瘤的TNM分期及肝内门静脉浸润呈正相关 ;CollⅣ与肝内门静脉浸润呈正相关、与术后生存期呈负相关 ;Lam与肝硬化及术中出血量呈负相关、与术后生存期呈正相关。PCNA与肿瘤TNM分期有关。结论 在HCC中 ,CollⅣ、vWF、及CD31为肝细胞肝癌的有效血管新生及预后指标 ;Lam则与肝硬化及术中出血相关 ;PCNA指数肿瘤分期有关 ;CD34不能用作血管新生或预后指标  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   
8.
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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Eighteen men (mean age 27, range 18-30 years) treated for Hodgkin's disease with 6-8 courses of MVPP (Mustine, Vinblastine, Procarbazine and Prednisolone) have had Leydig cell function assessed by their steroidogenic responses to stimulation by a single bolus dose of HCG (1000 units intramuscularly). Normal age-matched men (n = 16) acted as controls. Baseline immunoreactive FSH was markedly raised in the patients (mean 18.1 +/- SD 6.9 vs 2.0 +/- 1.5 IU/l, P less than 0.0001) reflecting damage to the germinal epithelium. Immunoreactive LH was also greater in patients (10.3 +/- 3.9 IU/l) than in controls (3.9 +/- 1.9 IU/l, P less than 0.0001). There were no differences between the baseline testosterone, androstenedione, oestradiol, oestrone and sex hormone binding globulin (SHBG) concentrations. The testosterone/SHBG ratios were similar in the two groups and there was no correlation between baseline LH and testosterone concentrations or testosterone/SHBG ratios. Testosterone, androstenedione, oestradiol and oestrone secretion in response to HCG stimulation were similar at 24 h and 96 h in both groups. In order to explain the paradox of elevated immunoreactive LH in the face of normal testicular steroidogenesis in such patients, LH biological activity (B) as well as LH immunoreactivity (I) and FSH and testosterone were estimated in a second similar group of patients (n = 17, mean age 27, range 17-43 years) and in a further age-matched control group (n = 17). Bioactive and immunoreactive LH levels were significantly increased (P less than 0.005 and P less than 0.001, respectively) in the patient group.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
10.
Membrane flow within the myelin sheath in IDPN neuropathy   总被引:1,自引:0,他引:1  
This report describes some aspects of beta,beta'-iminodipropionitrile (IDPN) neuropathy in rats as observed by ultrastructural methods and X-ray diffraction. Light microscopy shows gross swelling of the axons in proximal lumbar spinal roots 8 days after intraperitoneal injection of IDPN. Mean axon cross-sectional area and mean axon perimeter increased to 280% and 160% of their control values, respectively. At the same time, myelin membrane packing was not visibly disturbed. In addition, X-ray diffraction patterns, recorded under physiological conditions, demonstrate that the myelin lipid bilayer thickness and widths of the aqueous spaces between bilayers did not change. Related observations are made on posterior tibial nerve (PNS myelin) and ventral spinal cord (CNS myelin). The various observations together are interpreted in terms of a fluid myelin membrane. It is proposed that the myelin membrane flows during axon swelling even though normal membrane-membrane contacts are maintained within the sheath. Membrane flow and slippage between membranes are explained in terms of a molecular model of the myelin multilayer.  相似文献   
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