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31.
An unusual case of encephalomyeloneuritis associated with germ cell tumor with mature and immature teratoma arising in the mediastinum is presented. There was an unusually long interval from the onset of neurologic symptoms to the development of malignancy. The histopathology, characterized by limbic encephalitis, brain stem encephalitis, cortical cerebellar degeneration and myeloneuritis, was similar to that of paraneoplastic encephalomyeloneuritis previously described in the literature. Virological and immunological studies failed to demonstrate any causative agents or autoantibodies reacting with brain tissue. The causal relationship between the malignant neoplasm and encephalomyeloneuritis thus seems to be very complex.  相似文献   
32.
Regional cerebral blood flow after occlusion of the middle cerebral artery   总被引:3,自引:0,他引:3  
Occlusions of the middle cerebral artery (MCA) are mostly of embolic origin (appr. 80%) and give rise to about one third of all ischemic strokes, most of these being major strokes. MCA occlusions lasting for less than 1/2 h are tolerated without occurrence of permanent tissue damage. Occlusions lasting between 1/2 h to 4-8 h lead to permanent tissue damage and neurological deficits that are proportional to the duration of occlusion. Maximal tissue damage is obtained after 4-8 h occlusion. A cerebral blood flow of 8-23 ml/100 gr/min is sufficient for cellular viability but insufficient for normal tissue function ("ischemic penumbra"). Cellular function is completely abolished in the interval 8-16 ml/100 gr/min and flow at that level is tolerated only for 1-3 h before neuronal death ensues. In the interval 18-23 ml/100 gr/min there is some functional activity although it is reduced. Experimental and clinical evidence suggests that flow in this interval may be tolerated for several days, months or even longer ("chronic ischemic penumbra"). After MCA occlusion the blood flow falls below 8 ml/100 gr/min in most cases and permanent MCA occlusion always leads to relatively large areas of frank infarction. The ischemic infarcts may be surrounded by collaterally perfused areas where the blood flow is pressure-dependent (impaired autoregulation) and quite commonly insufficient for normal neuronal function (below 23 ml/100 gr/min). Such collaterally perfused areas may include a "chronic ischemic penumbra". Emboli causing MCA occlusions commonly disintegrate and/or migrate more peripherally within the first few weeks post stroke. This leads to reperfusion and changes of ischemic infarcts into hyperemic infarcts where flow is severely increased. The vascular reactivity is completely abolished in hyperemic infarcts and the hyperemic state lasts for about two weeks. Probably, anemic infarcts are equivalent to ischemic infarcts while the hemorrhagic variety is equivalent to hyperemic infarcts. The "partial infarct" with selective neuronal necrosis occurs in experimental animals after MCA occlusions of less than four h but not after permanent MCA occlusion. The significance of partial infarction in human stroke is not clarified. The extent of irreversible tissue damage can be reduced only if therapy sets in within 4-8 h after the occlusion. If a "chronic penumbra" exists the extension of reversible tissue damage can be reduced if therapy aimed at increasing the blood flow in the penumbra sets in within weeks or even months after the stroke.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
33.
Analysis of different cellular fractions after incubation of SW 948 and SW 707 colorectal carcinoma cells or WM 266-4 melanoma cells with 125I-insulin revealed the nondegraded hormone in the chromatin of these cells. Nuclear 125I-insulin was bound to specific fragments of EcoRI-, HaeIII-, and HincII-digested chromatin. A 45-kDa chromatin protein species that binds 125I-insulin was identified. Actinomycin D and cycloheximide inhibited the insulin-stimulated expression of chromatin receptors. Uptake of 125I-insulin by isolated nuclei occurred only in the presence of plasma membranes. Thus, at least some effects of insulin on target cells can be explained by direct gene regulation instead of "second messenger" action.  相似文献   
34.
Renal osteodystrophy (ROD) accompanied by long-term hemodialysis patients with chronic renal failure includes several forms of disorders of mineral and skeletal metabolism such as osteitis fibrosa attributed to secondary hyperparathyroidism, osteomalasia and adynamic bone disease. Bone scan is performed to detect of the mainly pathophysiology of ROD. We investigated bone scan of 25 hemodialysis patients with secondary hyperparathyroidism diagnosed clinically before and after parathyroidectomy (PTX). Before PTX an diffusely high accumulation of bone seeking agent in the whole skeleton especially skull in all patients (100%), vertebra in 24 out of 25 (96%), patella in 24/25 (96%), limbs in 23/25 (92%), sternum in 19/25 (76%), sacrum in 18/25 (72%) and costochondral junctions in 14/25 (56%) was noted in these patients. The radionuclide activity of the calvaria, maxilla and mandible in the skull was prominently high. Fourteen patients had an equally high activity in the calvaria, maxilla and mandible, 6 patients had higher activity in the maxilla and mandible than that of calvaria and 5 patients had higher in the calvaria than that of maxilla and mandible. After PTX the changes in the skull were obvious in 19 patients who showed a more markedly decreased in activity of the maxilla and mandible than that of the calvaria. In 3 patients showed a more markedly decreased in activity of the calvaria than that of the maxilla and mandible. Another 3 demonstrated equally decreased in activity in the calvaria, maxilla and mandible. It became clear that the highest activity of the skull was shown in all patients and the therapeutic changes of the skull are the most pronounced in maxilla and mandible in this study.  相似文献   
35.
36.
BACKGROUND: To investigate the in vitro effects of propofol on blood coagulability and fibrinolysis by the use of thromboelastograph (TEG) technique. METHODS: The blood samples, obtained from 14 healthy volunteers, were divided into two groups: propofol (n = 7) and intralipid (n = 7), and 360 microliters volumes of whole blood were incubated with 2 microliters of 1% propofol and with its solvent intralipid, respectively. The incubated sample was then used for TEG measurements. RESULTS: The maximum amplitude (MA), which reflects coagulability, in the intralipid group significantly increased by about 7% and 16% compared to the control and propofol groups, respectively (P < 0.05), whereas the MA in the propofol group did not change. The fibrinolytic rate (FR) in the propofol group significantly increased by about 170% and 210% compared to the control and intralipid groups, respectively (P < 0.05), whereas the FR in the intralipid group did not change. CONCLUSIONS: Propofol, per se, has at the concentration of 55.6 micrograms.ml-1 an in vitro accelerative effect on blood fibrinolysis detected by TEG.  相似文献   
37.
以流行病学在病证结合的中医“证”研究中的应用为线索,光盘检索和手工查阅了1997—2002年的期刊文献,对若干疾病运用流行病学方法进行的大样本(100例以上)的中医证型临床研究结果作一个回顾和小结,从流行病学和统计学的角度分析科研和论文中存在的问题,提出改进方法和展望。  相似文献   
38.
OBJECTIVE: Our goal was to evaluate the role of intraoperative cystoscopy during surgery for pelvic organ prolapse and urinary incontinence. STUDY DESIGN: Charts of 224 consecutive patients who had intraoperative cystoscopy performed after urogynecologic surgery were reviewed. RESULTS: Nine injuries occurred that were unsuspected before cystoscopy, for an incidence of 4%. Six ureteral ligations occurred, four after Burch cystourethropexy and two after vaginal culdoplasty. Intravesical sutures were noted after two Burch procedures, and another injury occurred with passage of fascia lata through the bladder during a pubovaginal sling procedure. Eight injuries were managed by removal and replacement of the suture or sling with only one requiring ureteroneocystotomy. When patients with injuries were compared with those without, there were no statistical differences in demographic or surgical parameters. CONCLUSIONS: The potential for damage to the lower urinary tract is significant with complex urogynecologic surgery. Because of the increased and delayed morbidity associated with unrecognized injury, intraoperative surveillance cystoscopy should be considered a part of all such procedures.(Am J Obstet Gynecol 1997;177:71)  相似文献   
39.
Although the osteosarcoma is considered to be among the most chemosensitive malignancies and preoperative chemotherapy is commonly applied, an appreciable proportion of cases are in fact quite insensitive. Predictive markers for chemosensitivity are therefore desirable in order to develop effective treatment strategies. Thirty-two cases of conventional osteosarcomas treated at the Cancer Institute Hospital, Tokyo, were analyzed. The sensitivity to preoperative chemotherapy was investigated with reference to loss of heterozygosity (LOH) at the 17p13 ( p 53) and 13q14 ( Rb ) loci and expression of the cell-cycle associated proteins, p53, Rb, p21/Waf-1, mdm-2 and Ki-67, as detected immunohistochemically. LOH was detected by analyzing polymerase chain reaction products at marker microsatellite loci. The efficacy of chemotherapy was evaluated both radiologically and histologically. LOH at p 53 or Rb loci was seen in 54% (13/24) and 58% (14/24) of cases, respectively. Only 15% of osteosarcomas with LOH at the p 53 locus were sensitive to preoperative chemotherapy, as compared to 64% of tumors without such loss ( P <0.05). A similar but much less distinct tendency was observed with LOH at the Rb locus. No relationship was evident between chemosensitivity and immunohistochemical staining patterns for p53, Rb, p21/Waf-1, mdm-2 or Ki-67. The results suggest that p 53 gene deletion, but not the other parameters investigated, may be useful for predicting chemoresistance of osteosarcomas.  相似文献   
40.
Induction of antitumor immunity to T-9 rat glioma by intracellular hyperthermia using functional magnetic particles was investigated. Magnetite cationic liposomes (MCLs), which have a positive surface charge, were used as heating mediators for intracellular hyperthermia. Solid T-9 glioma tissues were formed subcutaneously on both femurs of female F344 rats, and MCLs were injected via a needle only into the left solid tumors (treatment side). The rats were then divided into two groups, which received no irradiation, or irradiation for 30 min given three times at 24-h intervals with an alternating magnetic field (118 kHz, 384 Oe). On the treatment side, the tumor tissue disappeared completely in many rats exposed to the magnetic field. The tumor tissue on the opposite side also disappeared completely, even though MCLs were not injected into the right solid tumors. To examine whether a long-lasting and tumor-specific immunity could be generated, the rats that had been cured by the hyperthermia treatment were rechallenged with T-9 cells 3 months later. After a period of transient growth, all tumors disappeared. Furthermore, immuno-cytochemical assay revealed that the immune response induced by the hyperthermia treatment was mediated by both CD8+ and CD4+ T cells and accompanied by a marked augmentation of tumor-selective cytotoxic T lymphocyte activity. These results suggest that our magnetic particles are potentially effective tools for hyperthermic treatment of solid tumors, because in addition to killing of the tumor cells by heat, a host immune response is induced.  相似文献   
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