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1.
Summary We report the case of a patient who, over a 20-month period, developed overt B-cell non-Hodgkin's lymphoma in a T-cell rich background initially indistinguishable from reactive lymphoid aggregates in bone marrow. This morphological pattern of B cell lymphoma has been termed T-cell-rich B-cell lymphoma and, to our knowledge, has not previously been reported with a primary bone marrow presentation. Of additional interest, the patient's initial presentation was with myelodysplasia which appeared morphologically to resolve as the lymphomatous population emerged. Subsequently, however, the patient developed overt acute myeloid leukaemia (AML) and demised. This patient appeared to have two distinct neoplastic processes occurring in his bone marrow. The relationship between the two remains a matter of speculation.  相似文献   
2.
Dominantly inherited tubular aggregate myopathy.   总被引:1,自引:0,他引:1  
We report an unusual familial myopathy characterized morphologically by the presence of large tubular aggregates in all fibre types. Two patients, a father and daughter, presented with slowly progressive proximal weakness, limitation of eye movement, and Achilles tendon contractures. Serum creatine kinase was 5-10 times normal. Light microscopy revealed type I fibre predominance. Basophilic accumulations, which stained intensely with the NADH-TR reaction, were present in both fibre types. Electron microscopy revealed that these consisted of tightly packed parallel tubular arrays. These varied somewhat in their ultrastructural appearance and were classified accordingly as type I, II, and III tubular structures. The tubular aggregates appear to be derived from the sarcoplasmic reticulum. This report further supports the evidence of a distinct clinico-pathological entity of genetic origin.  相似文献   
3.
4.
The covalent binding reaction of the third component of complement (C3) with rabbit IgG immune aggregates has been studied by enzymic digestion of C3b-IgG adducts. In these adducts C3b was radioactively labeled in the free thiol group generated during activation of the internal thioester of C3. Trypsin digestion of 14C-labeled C3b-IgG adducts degrades C3b to a small antibody-bound 14C-labeled C3 fragment (14C-C3frg), whereas the antibody remains unaltered. Papain digestion of trypsin-treated 14C-C3frg-IgG complexes generated Fc and Fab fragments bearing equivalent amounts of covalently bound 14C-C3frg (43% and 40%, of the total C3 present in the aggregates, respectively). Hydroxylamine treatment of the 14C-C3frg-Fab and 14C-C3frg-Fc complexes released a 14C-C3frg of similar size (about 3–4 kDa) in which the N-terminal residue was the radiolabeled Cys1010. A fragment with the same radioactive N terminus and characteristics was obtained by sequential trypsin and papain digestion of purified C3 labeled with iodo–[14C] acetamide. Affinity-purified 14C-C3frg-Fc complexes digested with pepsin generated a mixture of radioactive peptides, most probably complexes formed by 14C-C3frg and Cγ2 or the hinge digestion products, and 14C-C3frg-pFc' complexes. The latter was also immunoprecipitated with anti-Fc-Sepharose from the pepsin digestion supernatants of 14C-labeled-C3b-IgG complexes. Taken together these data indicate that, during complement activation through the alternative pathway by IgG immune aggregates, C3 is not bound to a single site on the antibody molecule. Both Fab and Fc regions of IgG are equally efficient targets for C3 anchorage. In addition, the data confirm the pFc' as a region of C3 attachment within the Fc portion, and strongly suggest that C3b is bound either to the Cγ2 domain or the hinge or both.  相似文献   
5.
Summary A 23-year-old man with myopathy with tubular aggregates had suffered from exercise-induced muscle cramps for 1 year. His general and neurological findings were normal. Laboratory investigations were within normal limits except for a slightly elevated serum creatine kinase level. Muscle biopsy showed some small angular fibres and scattered type 2B fibres with prominent tubular aggregates originating from the sarcoplasmic reticulum. Since the muscle fibres contracted at a lower concentration of caffeine, increased muscle fibre sensitivity to caffeine is probably related to muscle cramps in this disorder. Tubular aggregates are then secondarily formed in the muscle fibres.  相似文献   
6.
In experiments on frog urinary bladder the mechanisms behind the gradual development of a hydroosmotic reaction to antidiuretic hormone (ADH) were investigated. It was suggested that the velocity of hydroosmotic reaction may be limited by (a) formation and insertion of particle aggregates into the apical membrane or (b) by velocity of cAMP formation. The urinary bladders were exposed to 23 nM ADH for different times (from 1 to 20 min) and water flow was measured over a period of 40 min. It was found that the value of the full hydroosmotic response increased progressively with the time of exposure to the hormone; however, the enhancement of water flow was equal during each time interval before reaching the reaction maximum. A direct correlation between the value of ADH-stimulated water flow, cAMP content in bladder tissue and frequency of particle aggregates in the granular cell apical membrane was observed. The content of cAMP in ADH-treated bladders was higher by 80% in the absence than in the presence of an osmotic gradient. Pretreatment of urinary bladders with 50 M cyclic nucleotide phosphodiesterase inhibitor, 3-isobutyl-1-methylxanthine, significantly accelerated the development of the hydroosmotic reaction and increased the magnitude of water flow in comparison with the effect of ADH only. No changes in cyclic AMP phosphodiesterase activity were found in the urinary bladder homogenates under the action of ADH, so it seems likely that accumulation of cAMP depends only on the increase of adenylate cyclase activity. The data obtained allow one to conclude that the gradual hydroosmotic response to ADH depends on the accumulation of cAMP, which may be considered as the main limiting factor of the velocity of the hydroosmotic reaction.  相似文献   
7.
The effects of Nd-YAG laser irradiation on platelet function in vitro were studied using platelet rich plasma obtained from the blood of healthy volunteers. Laser delivery was effected via the bare optical fibre, thermal hot tip fibre and spectraprobe and the effects of these probes on platelet function were compared. Fall in platelet count and mean platelet volume (MPV) were proportional to increasing energy delivery with all three probes, the effect being maximal with the spectraprobe, moderate with the hot tip and least with the bare optical fibre. A significant decrease in percentage aggregation of platelets in response to added ADP, collagen and ristocetin with increasing energy delivery was also observed with all three probes. The formation of preformed aggregates, however, showed an increase proportional to energy delivery with all three probes.The differential effects of the various probes used in this study on platelet function may enhance our understanding of the complex role played by platelets in the pathogenesis of complications such as arterial thrombosis and re-occlusion after laser angioplasty.  相似文献   
8.
Summary In a case of congenital paramyotonia a muscle biopsy was performed and studied morphologically, histochemically and ultrastructurally. A clearcut pattern of changes has been observed with ATPase and oxidative enzymes. On electron microscopy special changes known as tubular aggregates were found. The relationship between the two findings, as well as the significance of such alterations in the range of periodic paralyses and myotonic phenomena, are discussed.
Zusammenfassung Bei einem Fall von kongenitaler Paramyotonie wurde eine Muskelbiopsie lichtmikroskopisch, histochemisch und elektronenoptisch untersucht. Typische Veränderungen ergaben sich in der ATPase-Färbung und in bezug auf oxydative Enzyme. Bei der elektronenoptischen Untersuchung wurden sogenannte tubuläre Aggregate festgestellt. Es wird die Beziehung der zwei Gruppen von Veränderungen zueinander diskutiert sowie auch die Bedeutung derselben im Rahmen der periodischen Lähmungen und der myotonen Phänomene.
  相似文献   
9.
Summary

The authors summarize their experimental experience with the evaluation of lymphocyte changes following exogenous irradiation, and their diagnostic and prognostic value for the assessment of damage in the post-irradiation syndrome.  相似文献   
10.
目的探讨血小板与单核细胞聚合物(platelet—monocyte aggregates,PMA)在2型糖尿病(type 2 diabetes mellitus,T2DM)患者血管病变诊断中的意义。方法应用荧光标记单抗流式细胞术对94例T2DM患者(按有无血管并发症分为有血管并发症组64例和无血管并发症组30例)和42例健康刘照者血清中PMA表达率及实验室常规检测指标进行分析。结果T2DM患者组血清中的PMA表达率明显高于健康对照组,且差异有统计学意义(P〈0.01)。有血管病发症组患者血清中的PMA表达率高于无血管病发症组,且两组间差异亦有统计学意义(P=0.015);糖尿病患者血管病变损伤区域数量≥2时,其PMA表达率明显高于无血管病变患者组,且差异均有统计学意义(P均〈0.05)。PMA表达率与RBC、WBC、HGB、高密度脂蛋白胆固醇等均有一定相关性(P均〈0.05)。受试者工作特征曲线显示PMA表达率为24.72%时,对T2DM血管并发症诊断的灵敏度为71.9%,特异性为73.8%,曲线下面积为0.754。结论T2DM患者血清中的PMA表达率明昆升高,日升高的程度与糖尿病血管病变数量有关。  相似文献   
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