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71.
A. Bischoff 《Acta neuropathologica》1970,15(2):142-155
Summary Electron-microscopic investigations of the spinal cord in adult chickens poisoned with TOCP (Tri-Ortho-Cresyl Phosphate) show pathological alterations as early as the first day after appearance of the clinical symptoms. Of the same qualitative order as in the peripheral nervous system, they refer to the nerve fibres in the white matter in form of primarily diseased axons, with proliferation of the endoplasmic reticulum and disintegration of the neurofilaments. In the grey substance of the anterior horn, in particular, one sees severe structural alterations in the boutons terminaux while the motoneurons are hardly modified. The most striking finding already in the early stage is a massive swelling of the spherical synaptic vesicles in the boutons of theS-type, attributed to axo-somatic synapses.This work was supported by the Swiss National Foundation (Grant No. 3503). Part of the work was carried out at the Research Laboratory, McLean Hospital, Belmont/Mass. under the direction of J. D. Robertson. 相似文献
72.
The phenotype of lymphocytes, obtained from mice immunized with allogeneic tumor cells, with the capacity to induce macrophage cytotoxicity was determined. Macrophage cytotoxicity was induced, either by incubating the macrophages with Macrophage Arming Factor (MAF) containing supernatants of cultures of sensitized lymphocytes and tumor cells (arming) or by incubating the macrophages directly with sensitized lymphocytes and tumor cells (activation). The MAF producing or activating capacity of the lymphocytes was not only "triggered" by the sensitizing tumor cells but also by normal cells and other tumor cells bearing the H-2 determinants of the sensitizing tumor cell. The capacity to render macrophages cytotoxic was not reduced after treatment of the lymphocytes with mitomycin-C or treatment with anti-murine Ig and complement. This capacity of the lymphocytes was abrogated after treatment with anti-T-cell serum or anti-Thy 1.2 serum and complement. After treatment with anti-Lyt 1 or anti-Lyt 2 serum and complement, the activating capacity was significantly reduced and the MAF producing capacity of the lymphocytes abrogated. Mixing the Lyt 1 depleted and Lyt 2 depleted lymphocytes or addition of normal lymphocytes to the Lyt 1 depleted or Lyt 2 depleted populations did not restore the MAF producing and activating capacities. This indicated that the lymphocytes inducing macrophage cytotoxicity in this allogeneic system are Lyt-1+2+ T-lymphocytes, which do not need to divide prior to perform their action. 相似文献
73.
74.
Blaszak RT Mitsnefes MM Ilyas M Salman SD Belcher SM Brady DR 《Pediatric nephrology (Berlin, Germany)》2005,20(7):967-971
Hyperphosphatemia has been associated with the development of secondary hyperparathyroidism, renal osteodystrophy, cardiovascular calcification and increased risk of death. Using a one group, pretest-posttest study design, we sought to evaluate changes in serum phosphorus, calcium, parathyroid hormone and subject knowledge in response to a 3-month educational intervention. Mean serum phosphorus levels did not differ significantly between the three evaluation periods: pretreatment (5.69 mg/dl), treatment (5.84 mg/dl) and posttreatment (6.17 mg/dl). Mean serum calcium, calcium-phosphorus product and PTH values also did not differ significantly between the treatment periods. We observed no difference between the subject test scores between the two testing periods. Calcium-phosphorus product, serum phosphorus and PTH values on average, despite the education program, remained outside the K/DOQI target guidelines 44, 56 and 81% of the time, respectively. The results of this study suggest that an aggressive 3-month patient education program targeting dietary phosphorus knowledge, phosphate binder name and dosing, and knowledge of medical consequences associated with non-compliance had no effect on the serum phosphorus, calcium, PTH or phosphate binder need. 相似文献
75.
Cytogenetic studies were carried out on the spontaneous transplantable murine B cell leukemia (BCL1) of BALB/c mice, a recently discovered model of chronic lympholytic leukemia. BCL1 tumor cells appear as medium to large size mature lymphocytes located predominantly in the blood (up to 500,000/mm3) and in the x50 enlarged spleen. BCL1 cells obtained from the spleen show a certain degree of spontaneous proliferation unlike peripheral blood lymphocytes (PBL), but both show a good in vitro response to the B-cell mitogen lipopolysaccharide (LPS). Out of 213 spontaneously dividing spleen cells and LPS stimulated PBL studied, the majority (75.5%) showed a rather stable and complex female karyotype consisting of 36 chromosomes. No normal representative of chromosome Nos. 6, 8, 12 and 15 was present and only one normal representative was found for chromosome Nos. 4, 5, 9, 14 and X. Two deleted chromosomes and seven characteristic marker chromosomes, originating from complex chromosomal rearrangements could be identified in each cell. Of special interest was the t(12:15) translocation, which had been found in several murine plasmacytomas. No direct correlation between the chromosomal changes and the phenotypic characteristics of BCL1 tumor cells could be made. However, the highly specific karyotype may serve as a useful marker in identifying single BCL1 tumor cells. 相似文献
76.
Summary High-resolution31P NMR spectroscopy is shown to be a potentially valuable new method for monitoring the spontaneous precipitation of calcium
phosphates from metastable supersaturated solutions. An apparatus capable of pH-statting the sample in a spinning 20 mm NMR
sample tube is briefly described. The spontaneous precipitation of dicalcium phosphate dihydrate, CaHPO4· 2H2O, pH-statted at pH 5, is characterized by a base-uptake curve which follows the decrease in the intensity of the solution31P resonance. The precipitation of amorphous calcium phosphate at neutral pH, which exhibited an induction period of ∼ 10 min,
was also studied. No evidence of NMR peaks from transient clusters or the initial colloidal solid phase has been seen. 相似文献
77.
We previously isolated 31 cDNAs corresponding to pdi [inorganic phosphate (Pi) deficiency-inducible] genes through the differential screening of a cDNA library constructed from the mycelium of Pholiota nameko strain N2 cultured in Pi-depleted medium. Among the cDNAs, pdi251, pdi263 and pdi315 were analyzed here. The deduced amino acid sequences of pdi251, pdi263 and pdi315 showed high similarity to fungal hydrophobins and genes corresponding to these cDNAs encoding P. nameko hydrophobins were designated pnh1, pnh2 and pnh3, respectively. PNH1, PNH2 and PNH3 had a conserved spacing of eight cysteine residues in hydrophobins and a hydropathy pattern characteristic of class I hydrophobins. Phylogenetic analysis showed that PNH1, PNH2 and PNH3 were phylogenetically similar and significantly related to the hydrophobin POH1 specifically expressed in fruiting bodies of Pleurotus ostreatus. Northern blot analysis indicated that, under conditions of Pi deficiency, pnh2 and pnh3 were also induced in strains N4 and N301.Communicated by U. Kück 相似文献
78.
三邻甲苯磷酸酯暴发中毒四年的临床观察 总被引:2,自引:0,他引:2
目的:了解三邻甲苯磷酸酯(TOCP)暴发中毒患者的临床特征,并探讨其诊断的敏感指标。方法:对70例TOCP中毒患者4年的临床资料进行了分析。结果:患者临床表现符合迟发性中枢-周围远端型轴索病,食人TOCP的面粉后有一段无症状期,平均46d,其间无任何胃肠道症状和毒蕈碱样症状,麻痹前突出的症状为腓肠肌疼痛(95.7%),是本组患者的首发症状,3-7d后,出现由下肢远端开始的多发性周围神经病表现;重度中毒患者(20例)于发病1个月左右开始出现上运动元麻痹的表现。所有神经损害的表现下肢均早于并重于上肢,远端重于近端,7个月左右时,轻度中毒患者肢体功能大多基本恢复到病前水平;而重度中毒患者锥体束损害的表现却更加突出,100%有肢体残疾。在第1个月和第48个月,对10例中毒患者作神经肌电和诱发电位(EP)检查,结果表明,下肢肌电图(EMG),运动神经传导速度(MCV)均异常;下肢运动诱发电位(MEP)异常4例,均为中枢运动通路传导时间(CMCT)延长,上肢体感诱发电位(SEP)异常2例,下肢SEP全部异常,TOCP中毒尚无特效疗法,常用BY笔维生素,ATP等治疗,恢复期针灸,按摩等有助于肢体功能的恢复。结论:腓肠肌疼痛对TOCP中毒具有诊断价值,EMG,神经传导速度,EP检查可作为诊断的敏感指标。 相似文献
79.
Koichiro Tamanaha Robert H. K. Mak Susan P. A. Rigden Charles Turner Kathryn M. Start George B. Haycock Cyril Chantler 《Pediatric nephrology (Berlin, Germany)》1987,1(2):145-149
Forty-five children with stable chronic renal failure, not on dialysis, were treated conservatively with a regimen of mild dietary phosphate restriction and high-dose phosphate binders for up to 5 years. Both aluminum hydroxide and calcium carbonate were used initially, but almost all patients were taking calcium carbonate towards the end of the period. Serum immunoreactive parathyroid hormone concentrations were significantly decreased and were within the normal range after 1 year and remained normal during treatment. There was no significant change in renal function over the same treatment period. We conclude that calcium carbonate should be used as the phosphate binder of choice in the long-term suppression of hyperphosphatemia and hyperparathyroidism in uremic children. 相似文献
80.
为了寻找测定组织钙调素含量的非放射性同位素方法,我们对 Peter 等的超微量定磷法的稳定剂和反应体积加以改进,并对其它影响因素进行了探讨。其灵敏度达到50ng,测定范围0.05—1.0ug,4小时内稳定。本方法亦适用于有机磷化合物存在下的无机磷含量测定。 相似文献