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991.
The authors reported the first case of acute spinal epidural hematoma (SEH) developed after open heart surgery. The patient was noticed that her legs felt weak and numb on the first postoperative day evening. On the next day morning, neurological examination revealed that flaccid paralysis of both legs and also loss of all sensory perception below the level of Th-6 spine bilaterally. The prolonged effect of anesthesia and painless onset made delayed recognition of the lesion. SEH (Th5-7) was diagnosed with MRI and decompressive surgery was immediately done, sixty hours after the beginning of cardiac operation. But in this case neurological deficits were not changed. We concluded that a routine diagnostic approach was very important procedure to find out this serious complication for all patients underwent open heart surgery in early period of its onset.  相似文献   
992.
Spontaneous mutation during fetal development and post-natal growth   总被引:3,自引:1,他引:2  
Somatic mutations seem to accumulate slowly with age duringadult life in both mice and men. There is, however, a substantialmutant frequency at birth, suggesting that the rate of accumulationis much higher before birth. This suggests that DNA replicationplays an important role in the generation of spontaneous mutations.Since most cell division and accompanying DNA replication occursearly in development, more mutations would arise during growthand development. Indeed, if the mutations are genetically neutral,the mutant frequency would rise very rapidly during early fetalgrowth, more slowly during later fetal growth and developmentand still more slowly after birth. To test this hypothesis,we have assayed the mutant frequencies from before birth to28 days after birth, by which time most growth has occurred.We have used the F1 mice generated by crossing SWR females andMutaTMMouse males. The MutaTMMouse has a rescuable lacZ/  相似文献   
993.
994.
OBJECTIVE: Chronic pancreatitis (CP) is a chronic condition associated with pancreatic fibrosis. A small subgroup of patients with CP develop enlargement of the head of the pancreas (EHP). This study examined some of the mechanisms that may lead to the development of EHP. SUMMARY BACKGROUND: The c-erb B-2 protooncogene encodes a 185-kDa transmembrane growth factor receptor (p185) that regulates cell growth and differentiation. METHODS: The authors analyzed c-erb B-2 expression in samples obtained from the head of the pancreas from 26 patients with CP (5 women, 21 men) using immunohistochemical and molecular technique. A diagnosis of CP with EHP was made when the vertical pancreatic head diameter was greater than 4 cm (14 patients), as determined by contrast-enhanced computed axial tomography scan. Pancreatic tissues from 15 healthy organ donors served as control subjects. RESULTS: In all patients without EHP and in the healthy control subjects, p185 immunoreactivity was present at low levels. In contrast, strong p185 immunoreactivity was observed in acinar and ductal cells in all patients with EHP. By in situ hybridization, c-erb B-2 messenger ribonucleic acid (mRNA) grains were expressed at high levels in patients with CP with EHP in both ductal and acinar cells. Northern blot analysis demonstrated a 4.5-fold increase (p < 0.001) in c-erb B-2 mRNA levels in patients with EHP compared with patients without EHP and healthy control subjects. Southern blot analysis did not reveal c-erb B-2 gene amplification or rearrangement. CONCLUSIONS: These findings indicate the c-erb B-2 is not overexpressed in most patients with CP. However, its overexpression in patients with CP with EHP suggest that c-erb B-2 may contribute to the pathophysiologic processes that lead to pancreatic head enlargement.  相似文献   
995.
996.
During past 30 years, we experienced 253 patients who underwent surgery for myasthenia gravis. Among these patients, 9 were associated with Graves' disease. No patients had thymoma. Five patients underwent thymectomy after they had become euthyroid by medical treatment, though four patients required subtotal thyroidectomy before thymectomy. One patient developed myasthenic crisis following thyroidectomy and was treated with respirator for 5 days. But thymectomy was performed without myasthenic crisis in these four patients between 25 days and 60 days after thyroidectomy. They have been doing well and no see-saw phenomenon was presented. Thymectomy is safe and effective even in the patients with Graves's disease, and we recommend to perform it after they become euthyroid by medical or surgical treatment.  相似文献   
997.
The authors presented a new posterior beam-stop (PBS) technique for measuring the ratio of scattered to total-detected photon flux (scatter fraction) in a radiographic examination while preserving the diagnostic quality of the image. The scatter measurement was made using a standard imaging geometry with both beam stops and an additional x-ray detector placed behind the standard imaging detector. This PBS geometry differs from the standard beam-stop (SBS) technique for scatter measurement. With SBS, a beam-stop shadow appears on the image. To evaluate the PBS technique, scatter fraction measurements were performed on an anatomic phantom using both the PBS and SBS techniques. When compared with the standard technique, PBS provided accurate estimation of scatter fractions. Since the measurement can be performed without degrading a standard clinical radiographic examination, the PBS technique allows simultaneous acquisition of scatter measurements from human patients in combination with a standard radiographic examination.  相似文献   
998.
In therapeutic plasmapheresis using cascade filtration, it is important to maximize albumin recovery while rejecting as many gamma-globulins as possible. Several membrane fractionation techniques were investigated using fresh bovine and human plasma and cellulose acetate filters (PF 100, AKZO). In dead end mode the sieving coefficients were found to decrease as transmembrane pressure increased. This was due to membrane plugging during the course of filtration after about 20 minutes which lead to a rapid increase in transmembrane pressure. In single pass mode the albumin recovery factor generally remains around 40% since the permeate flux is much less than the inlet flow. When strong pulsations (4 to 6 Hz) were superposed on the inlet plasma flow in single pass mode, the albumin sieving coefficient remained at about 0.95 while the permeate flux was increased by 106%. As a result a recovery factor of more than 80% could be sustained for at least 90 minutes without membrane plugging. Therefore pulsatile flow plasma fractionation seems to be an interesting approach to combine continuous operation with high albumin recovery.  相似文献   
999.
Maintenance of the body's perfusion by a total artificial heart (TAH) may result in physiological alterations to the circulatory system. Little has been said about modifications to systemic vascular resistances (SVR) during TAH assistance. This paper reports on two patients implanted with a Jarvik - 70 cc TAH, who died after 1 and 3 days, both with an irreversible drop of SVR related to a complete loss of vascular tone but not related to sepsis. Activation of multiple cascades of inflammation, triggered by the extracorporeal circulation (ECC), is maintained during TAH support. Desperately sick patients might not be able to face the vaso-active situations created by the inflammatory response.  相似文献   
1000.
Glomerulopathy and nephrotic syndrome were induced in rats by intravenous puromycin aminonucleoside. Ten days after the injection of puromycin, the animals have developed heavy proteinuria. During this phase, glomerular epithelial cell endocytosis was studied by injecting a conjugate of horseradish peroxidase and poly-L-lysine. This conjugate has been shown to be endocytosed by glomerular epithelial cells. The rats were serially sacrificed from 1 min to 24 h after this injection. Peroxidase was localised cytochemically and observed at light and electron microscopy. The early events of endocytosis in glomerulopathy (namely the binding to the plasma membrane, the membrane invagination and the formation of the early vesicles) were qualitatively similar to those in the normal. The later events (the fusion of the vesicles and their movement within the cells) were inhibited. The results show that puromycin aminonucleoside damages epithelial cell endocytotic activity and affects the later processing of the conjugate within the cells.  相似文献   
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