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941.
Excitotoxicity and epileptic brain damage. 总被引:5,自引:0,他引:5
B Meldrum 《Epilepsy research》1991,10(1):55-61
The two forms of epileptic brain damage, that found in patients with chronic epilepsy (post-mortem or in an anterior temporal lobectomy specimen) and that occurring acutely after status epilepticus, have much in common but are not identical. Hippocampal lesions occurring acutely after status epilepticus show a high degree of selectivity for hilar interneurones, CA1 pyramidal neurones and CA3 pyramidal neurones. Hippocampal lesions in anterior temporal lobectomy specimens tend to involve the subfields less selectively with CA1 being only slightly more severely affected than dentate granule cells, CA3 and CA2 pyramidal neurones. The most severely damaged hippocampi may result from a combination of acute damage early in life (commonly from prolonged febrile convulsions) and cumulative damage associated with seizures. Less severe degrees of damage are probably a consequence of repeated seizures. The abnormal patterns of firing associated with epileptic activity are almost certainly responsible for cell death occurring acutely after status epilepticus; they may contribute to the progressive cell loss occurring in chronic epilepsy. 相似文献
942.
D B Hackney R I Grossman R A Zimmerman P M Joseph H I Goldberg L T Bilaniuk 《Journal of computer assisted tomography》1986,10(3):401-403
Although iophendylate (Pantopaque) has been largely replaced by water soluble agents for myelography, retained intracranial or intraspinal Pantopaque remains a common occurrence. Pantopaque has signal characteristics similar to fat with both short T1 and T2 relaxation times. In vitro measurements revealed T1 = 170 ms and T2 = 27 ms. Spine radiography is recommended in patients with a history of previous myelography and magnetic resonance abnormalities similar to fat. 相似文献
943.
The electromyographic (EMG) interference pattern (IP) was measured in the biceps muscle of 16 normal male and 17 normal female subjects. The activity, upper centile amplitude (UCA), and the number of small segments (NSS) (defined in a companion paper) were measured from 500-msec epochs of the IP. The normal values of these features were defined separately for men and women by plotting the UCA and NSS values against activity for each epoch and defining an area on these plots, called a “cloud,” that contained more than 90% of the datum points from each study. The mean deviation of the individual datum points from the overall mean values was also calculated for each study. A study in one muscle is considered to be normal if more than 90% of the datum points from that muscle are within the normal clouds and the deviation values are within their normal range. In patients with neuropathy, the characteristic pattern was increased UCA with normal or decreased NSS. In patients with myopathy, NSS was increased and the UCA was normal or decreased. In all studies, the interpretations of the IP from the plots agreed with qualitative assessments of the IP made independently by an electromyographer. The use of these features to understand and quantitate the changes in the motor units produced by disease is demonstrated by serial studies performed in a patient with motor neuron disease. 相似文献
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947.
Richard B Thompson Ewout J van den Bos Bryce H Davis Yoshihisa Morimoto Damian Craig Brad S Sutton Donald D Glower Doris A Taylor 《The Journal of heart and lung transplantation》2005,24(2):205-214
BACKGROUND: Pre-clinical and clinical studies suggest that transplantation of bone marrow-derived stem cells can improve global cardiac function. However, no quantitative assessment of regional systolic contraction and correlation with phenotype has been made. Therefore, we used our model of cryoinfarcted rabbit myocardium for intracardiac transplantation of a mixed population of bone marrow-derived cells and assessed both regional function and myogenic conversion of the cells. METHODS: Nineteen New Zealand white rabbits underwent cryoinjury of the left ventricle. Autologous bone marrow (BM) cells were expanded in vitro. After 2 weeks, either 1 x 10(8) mixed BM-derived progenitor cells (BM group, n = 11) or vehicle (control group, n = 8) were injected into the cryoinjured region. Regional systolic function was measured using micromanometry and sonomicrometry before and 4 weeks after cell injection; cell phenotype was evaluated histologically. RESULTS: All animals in the BM group significantly improved both systolic shortening (0.11 +/- 0.7 vs -0.05 +/- 0.05 mm in the control group, p < 0.05) and regional stroke work when compared with control (9.6 +/- 2.4 vs -1.2 +/- 1.2 mm . mm Hg, p < 0.003). In addition, the BM group had improved global diastolic function, as measured by minimum dP/dt and end-diastolic pressure. On histologic assessment, BM cells differentiated toward a myogenic phenotype. CONCLUSIONS: Transplanting a mixed population of marrow-derived cells that can adopt a myogenic phenotype improves regional contractility and diastolic relaxation after myocardial infarction. 相似文献
948.
Gregory J. Pomper Rita A. Joseph Erica L. Hartmann Michael S. Rohr Patricia L. Adams Robert J. Stratta 《American journal of transplantation》2005,5(10):2586-2589
Massive immune hemolysis due to passenger lymphocyte-derived anti-D has not been reported in renal transplantation. A 50-year-old (B-positive) male received a dual deceased-donor kidney transplant (B-negative) for diabetic renal failure. Two weeks post-transplant, the patient developed severe hemolytic anemia. The donor anti-D titer was 1:8. The recipient anti-D titer (zero pre-transplant) increased from 1:4 to 1:16 over 4 days. Rapid hemolysis caused severe anemia, minimum Hb = 4.2 g/dL, while selectively lysing the patient's autologous red cells during this time. The hemolytic anemia did not impair the allografts and subsided without monoclonal B-cell pharmacotherapy or apheresis. The anti-D titer decreased to barely detectable levels at four months and had cleared when checked 2 years post-transplant. Transfusion support subsided after two months. If complications of anemia can be avoided, the deleterious effects of hemolysis may be well tolerated by renal allografts using antigen negative transfusion alone. 相似文献
949.
Pain in or symptomatic destruction of any number of the joints of the hindfoot can have several causes. As well as primary osteoarthritis, these include secondary arthrotic changes following fractures (especially of the talus and/or calcaneus), muscular and/or tenoligamentous instability (e.g., rupture of the posterior tibialis tendon, poliomyelitis, Charcot-Marie-Tooth disease), spastic and flaccid paresis of the lower leg and foot, late stages of various inflammatory arthritides (rheumatoid arthritis, seronegative spondarthritis, collagenoses), and neuropathic diseases with impaired depth perception (Charcot disease of the foot in diabetes mellitis, for example). As a general policy, only joints that are causing symptoms, are clearly arthritic, or are involved in a fixed foot deformity should be fused, so that as much of the residual hindfoot motion as possible is preserved. This helps to restrict future osteoarthritis in adjacent joints. The use of screws rather than staples seems to increase the fusion rates because this technique allows compression on the fusion. 相似文献
950.
Fahim Zaman Atta Nawabi Kenneth D Abreo Gazi B Zibari 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2005,9(3):262-265
Laparoscopic procedures continue to gain popularity over traditional open procedures for a number of abdominal and pelvic surgeries. With increasing experience, the application of this technique is rising because it provides an alternative, less invasive, approach to various surgical procedures. Herein, we report our experience with adult patients with polycystic kidney disease, requiring bilateral laparoscopic nephrectomy before renal transplantation. 相似文献