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21.
Tissue microarrays (TMA) consist of up to 1000 cylindrical tissue cores from different donor paraffin blocks relocated into one recipient block, allowing for efficient histopathological studies by fluorescence in situ hybridization, RNA in situ hybridization or immunohistochemistry. On the background of the increasing interest of the TMA technique in cancer research and the suggestion of its application also in studies of non‐neoplastic intracranial disorders, the technique was applied to pathologic white matter in AD brains. Eight cases with AD and concomitant white matter pathology were neuropathologically diagnosed on whole brain coronal slides. The TMA technique was used to grade severity of white matter pathology and to quantify small vessels with traditional staining and immunohistochemical markers. These measurements were compared with the whole brain neuropathological assessment. The technique produced good results with preserved tissue structures as confirmed by the whole brain evaluation. Severity of white matter pathology evaluated on the TMA cores correlated negatively with small vessel quantities, and statistically significant differences in vessel quantities paralleled different grades of white matter pathology. It is concluded that the TMA technique could be further utilized in studies of dementing disorders, and may have its advantages in large, clinically well‐characterized materials (e.g. in quantitative mapping of white matter changes).  相似文献   
22.
Both systemic and local therapy, for conditions of the breast and unrelated to it, may produce manuno-graphic changes. Some of these are characteristic, such as the pattern of scarring seen in reduction mammo-plasty. In many other instances, however, the changes produced overlap features commonly seen in malignancy. A knowledge of the timing, natural history and spectrum of these changes will aid mammographic interpretation.  相似文献   
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The time course and extent of changes in plasma prolactin, noradrenaline, vasopressin and oxytocin levels is reported following serial observations of a prolonged epileptic seizure arising in the temporal lobe, recorded by video-EEG-telemetry, in which the epileptic activity evolved from a simple partial to complex partial to secondarily generalised attack. The prolactin levels were markedly elevated during the phase of the simple partial seizure, at a time when consciousness was preserved, when motor activity was minimal and when EEG activity was highly localised. The hormonal levels continued to rise during the subsequent seizure evolution, suggesting that the duration (or intensity) of the seizure is an important, perhaps the most important, factor determining the degree of prolactin release during limbic seizures. Indeed, the prolactin elevation in this case (26 times the baseline level) is higher than any previously recorded, reflecting the unusual duration and intensity of this seizure. We did not observe the phenomenon of "exhaustion" of prolactin release and levels peaked after 49 min, and were high for over 2 h after the onset of the seizure, and after the convulsion had ceased. The concentrations of vasopressin, oxytocin and noradrenaline remained low during the aura, but rapidly increased during the phase of generalisation. The oxytocin and noradrenaline levels peaked during the phase of generalised convulsion, but the vasopressin levels peaked well into the post ictal phase, and remained high for several hours. The differing patterns of hormone release are likely to be related to the different anatomical sites of the hypothalamic perikarya, the relative importance of excitatory and inhibitory hypophysiotrophic agents in the release of anterior pituitary hormones and the localised release of neuromodulatory agents.  相似文献   
24.
管状骨增宽牵引成骨组织形态学变化的实验研究   总被引:10,自引:0,他引:10  
目的 探讨管状骨增宽牵引后新骨形成的变化。方法 在成年山羊的后肢放置2只增宽牵引器。实验组9只术后第8天牵引,对照组3只不牵引。牵引完毕后不同时期,各宰杀3只,评价管状骨增宽牵引后新骨形成的质和量。结果 实验组胫骨平均增宽7.83mm,X射线见牵引间隙逐渐变模糊,暴露侧有骨不连,非暴露侧成骨良好,牵引完毕3个月,未暴露侧新形成板层骨与原来胫骨融为一体,而暴露侧骨不连区为致密纤维组织。结论 管状骨增宽牵引成骨后,两侧牵引间隙成骨不一致,良好的血供,对新骨形成至关重要。  相似文献   
25.
Human cartilage link protein exists as three native components, while equine, bovine, and porcine cartilage link protein exist as two and Swarm rat chondrosarcoma link protein exists as only one component. These nonhuman link protein components represent intact protein structures, and there is little evidence for proteolytically modified forms in nonhuman tissues. In human cartilage, the proteolytic production of modified link proteins increases with age, whereas high amounts of such products were not seen in the nonhuman tissues. However, the small amounts of link protein fragments that were observed in the nonhuman cartilages were of a similar size to their human counterparts. On digestion of human proteoglycan aggregate with stromelysin, rapid modification of the link protein components occurred, whereas the aggregates from nonhuman cartilages showed incomplete cleavage of their link protein components. The relative resistance of nonhuman link protein to stromelysin may in part be due to a unique amino acid substitution present near the enzymic cleave site.  相似文献   
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目的 探讨椎动脉形态学异常对后循环TIA症状持续时间的影响。
方法 回顾性分析2015年10月-2018年3月在中国科学院大学重庆仁济医院神经内科完成头颈部DSA
或CTA的后循环TIA住院患者临床资料,根据症状持续时间分为<10 min组、10~59 min组和≥60 mi n组,
比较椎动脉形态异常各亚型在3组间的差异。通过多因素Logistic回归分析明确椎动脉形态异常与后
循环TIA症状持续时间之间的关系。
结果 共纳入237例患者,其中症状持续时间<10 min组109例(45.99%)、10~59 min组71例(29.96%)
和≥60 min组57例(24.05%)。一般临床资料的比较显示,性别、椎动脉和基底动脉狭窄率≥50%
在3组间差异具有统计学意义(P<0.05)。椎动脉形态异常中,动脉粥样硬化性椎动脉狭窄(狭窄
率1%~99%)在3组间的差异具有统计学意义(P =0.004),而一侧迂曲、双侧迂曲、一侧优势、一
侧优势合并迂曲和起源异常在3组间差异均无统计学意义;多因素Logi sti c回归分析显示椎动脉
狭窄(OR 2.500,95%CI 1.381~4.525,P =0.002)、基底动脉狭窄率≥50%(OR 12.066,95%CI
1.446~100.668,P =0.021)是TI A症状持续时间延长的独立影响因素。
结论 椎动脉狭窄和基底动脉狭窄率≥50%是影响后循环TIA症状持续时间延长的独立影响因素。  相似文献   
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Summary The in vitro effect of zinc on superoxide anion (O2?) generation and on experimentally induced lipid peroxidation (LPO) in spermatozoa of infertile men was investigated. Washed spermatozoa pre-incubated for 30 min at 37°C in the presence of 1 or 3 mmol l-1 zinc, released less superoxide anions (P<0.03 and P<0.02, respectively; n=9) than the untreated spermatozoa. Similar results were obtained using activated polymorphonuclear leukocytes (1 times 106 cells ml-1) in the presence of 1 or 3 mmol l-1 Zn (P<0.001 and P<0.0002, respectively; n=9). The in vitro evidence of the inhibitory effect of zinc on O2? generation by human spermatozoa and leukocytes indicates that zinc may act in vivo as a scavenger of excessive O2? production by defective spermatozoa and/or leukocytes in semen after ejaculation. A significant stimulatory effect of Zn (3 mmol l-1) on iron-induced lipid peroxidation, measured by the formation of thiobarbituric acid reactive substances (TBARS), was detected in the spermatozoa of 16 normo- and 17 asthenozoospermic males (P<0.0001 and P<0.001, respectively). In 11 samples with sperm concentration 20.3±2.1 times 106 ml-1, exhibiting initial TBARS concentration two times higher than in normo-and asthenozoospermic samples (40.5±2.4 vs. 17.1±1.1 and 28.5±4.1 nmoles TBARS 10-8 spermatozoa), no effect of zinc on the LPO rate was found. The observed inhibitory effect of zinc on superoxide anion regardless of the initial O2? level and stimulatory effect of zinc depending on the initial LPO rate in human spermatozoa suggests that this metal ion participates in the oxidative changes occurring after ejaculation and thus may modulate the properties of germ cells.  相似文献   
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