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121.
Transneuronal degeneration of retinal ganglion cells was directly demonstrated in a patient who had unilateral removal of the striate cortex forty years prior to necropsy. For comparison, another case is presented showing anterograde transneuronal atrophy forty years after enucleation of one eye.  相似文献   
122.
van Schaik  JP; Hawkins  IF  Jr 《Radiology》1985,155(3):829-830
A new technique is described for reversing the direction of the catheter tip during translumbar aortography, without the need for partial withdrawal of the catheter from the aortic lumen. The method ensures optimal delivery of contrast medium at the desired level, while avoiding the risk of retroperitoneal bleeding or dislodgement during catheter manipulation.  相似文献   
123.
Five patients with optic neuropathy, four vascular and one demyelinating, are described who each complained of an unusual symptom. Bright flashes of light (phosphenes) occurred in the affected eyes and were evoked by sudden unexpected sounds. Movement of the eye alone did not reproduce the symptom. In all patients the phenomenon was sufficiently prominent to interfere with sleep and was the main complaint of one patient. An anticonvulsant (phenytoin) greatly reduced the frequency and intensity of the phosphene in one patient.  相似文献   
124.
Differential CT diagnosis of extruded nucleus pulposus   总被引:1,自引:0,他引:1  
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Background Streptokinase resistance may cause suboptimal thrombolytic therapy. Aim To develop a rapid latex-bead assay to detect streptokinase antibodies. Methods Sera were obtained from 16 patients presenting with acute myocardial infarction (MI) before treatment with streptokinase and 1 and 6 months post treatment, and from 100 controls. Sera were assayed for anti-streptokinase antibodies using a functional streptokinase-neutralising assay. Results Streptokinase-neutralising activity was low in controls (54±5U/ml) and patients prior to treatment (101±18), increasing to 2,110±823 and 1,017±169 at 1 and 6 months (mean±SEM). The latex assay had a sensitivity of 94% and a specificity of 93% for detecting individuals with >350U/ml of streptokinase resistance, which is sufficient to neutralise the drug clinically. Conclusions Estimation of streptokinase resistance using an enzyme immunoassay and a latex bead assay correlated well with serum neutralising activity. This assay can rapidly identify patients who have a high level of streptokinase-neutralising activity.  相似文献   
128.

Background  

Neo-adjuvant chemotherapy is an integral part of multi-modality approach in the management of locally advanced breast cancer and it is vital to predict the response in order to tailor the regime for a patient. The common final pathway in the tumor cell death is believed to be apoptosis or programmed cell death and chemotherapeutic drugs like other DNA-damaging agents act on rapidly multiplying cells including both the tumor and the normal cells by following the same common final pathway. This could account for both the toxic effects and the response. Absence or decreased apoptosis has been found to be associated with chemo resistance. The change in expression of apoptotic markers (Bcl-2 and Bax proteins) brought about by various chemotherapeutic regimens is being used to identify drug resistance in the tumor cells. A prospective clinical study was conducted to assess whether chemotherapy induced toxic effects could serve as reliable predictors of apoptosis or response to neo-adjuvant chemotherapy in patients with locally advanced breast cancer.  相似文献   
129.
Maintenance of osmotic pressure is a primary regulatory process essential for normal cell function. The osmolarity of extracellular fluids is regulated by modifying the intake and excretion of salts and water. A major component of this regulatory process is the neuroendocrine hypothalamo-neurohypophysial system, which consists of neurons located in the paraventricular and supraoptic nuclei. These neurons synthesize the neurohormones vasopressin and oxytocin and release them in the blood circulation. We here review the mechanisms responsible for the osmoregulation of the activity of these neurons. Notably, the osmosensitivity of the supraoptic nucleus is described including the recent data that suggests an important participation of taurine in the transmission of the osmotic information. Taurine is an amino acid mainly known for its involvement in cell volume regulation, as it is one of the major inorganic osmolytes used by cells to compensate for changes in extracellular osmolarity. In the supraoptic nucleus, taurine is highly concentrated in astrocytes, and released in an osmodependent manner through volume-sensitive anion channels. Via its agonist action on neuronal glycine receptors, taurine is likely to contribute to the inhibition of neuronal activity induced by hypotonic stimuli. This inhibitory influence would complement the intrinsic osmosensitivity of supraoptic neurons, mediated by excitatory mechanoreceptors activated under hypertonic conditions. These observations extend the role of taurine from the regulation of cell volume to that of the whole body fluid balance. They also point to a new role of supraoptic glial cells as active components in a neuroendocrine regulatory loop.  相似文献   
130.
高效液相色谱法测定寒痹停片中士的宁含量   总被引:6,自引:0,他引:6  
目的:建立用HPLC测定寒痹停片中士的含量的方法。方法:氰基柱;流动相-甲醇-水-三乙胺-乙酸(9800:155:15:30);紫外检测波长254nm。结果:在4~20ug/ml范围内,标准曲线回归方程为:Y=-2803+8967x(r=0.9997),RSD=1.65%?加样回收率的平均值为99.82%。结论:实验表明,这是一个适用于生产控制和产品质量检验的简单、快速、准确的方法。  相似文献   
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