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21.
SUMMARY: It is desirable to estimate epileptogenic zones with both location and extent information from noninvasive EEG. In the present study, the authors use a subspace source localization method (FINE), combined with a local thresholding technique, to achieve such tasks. The performance of this method was evaluated in interictal spikes from three pediatric patients with medically intractable partial epilepsy. The thresholded subspace correlation, which is obtained from FINE scanning, is a favorable marker, which implies the extents of current sources associated with epileptic activities. The findings were validated by comparing the results with invasive electrocorticographic (ECoG) recordings of interictal spike activity. The surgical resections in these three patients correlated well with the epileptogenic zones identified from both EEG sources and ECoG potential distributions. The value of the proposed noninvasive technique for estimating epileptiform activity was supported by satisfactory surgery outcomes.  相似文献   
22.
本文报告了1990年5月以来脑干区大型、复杂占位病变15例.其中,位于脑干内3例,脚间窝2例,岩尖部4例,全岩骨区1例,全斜坡区2例,第四脑室内3例.本组采用以扩大了的岩骨入路为主的联合入路,行肿瘤全切除8例,次全切除5例.2例仅作了活检加减压术.除1例死亡外,均恢复良好.本文结合文献,对脑干区手术入路进行了讨论.  相似文献   
23.
Penetration of Schistosoma japonicum cercaria into host skin.   总被引:1,自引:0,他引:1  
The anterior part of Schistosoma japonicum cercaria is a specialized head organ which can slightly stretch out and retract. There are three different types of large unicellular glands in cercarial body, consisting of one head gland, 2 pairs of pre- and 3 pairs of postacetabular glands. These glands differ in position, gross feature, histochemistry and functions. Both polysaccharase and protease activities are demonstrated in the secretions from these glands. Mode of cercarial penetration is described in detail and the penetration is effected by a combination of lytic secretions and mechanical movements. The schematic representation of the process of cercarial penetration is presented. The dynamic distributions of schistosomula in skin at different time intervals after skin penetration in various mammalian hosts are shown. Some newly transformed schistosomula die while penetrating into the skin of 7 mammalian species and the mortality rate varies with the host species, and that can also be affected by the age of cercariae following emergence from the snail. Some physiological aspects between cercariae and newly transformed schistosomula are compared. In contrast to cercariae, schistosomula are saline-adapted and water-intolerant. They were modified histochemically and antigenically.
  相似文献   
24.
In an attempt to develop a new anticancer platinum complex with greater or equivalent antitumor activity but reduced side effects compared with cisplatin (CDDP), a series of new platinum complexes having a glycolate leaving ligand was synthesized. Among them, five complexes were selected for further development on the basis of adequate water solubility, low nephrotoxicity and high antitumor activity in a murine system. The chemosensitivity of these five complexes was examined in MTT assay against two human pulmonary adenocarcinoma cell lines, PC-9 and PC-14, and two human stomach adenocarcinoma cell lines, MKN-45 and KATO III. Their IC50 and relative antitumor activity (RAA) values were compared with those of CDDP and 254-S, a second-generation platinum complex with a glycolate leaving ligand under phase III clinical trial. The lowest mean IC50 value was observed in CDDP, followed by SKI 2034R and SKI 2033R. In this study, the antitumor activity was evaluated in terms of RAA values and SKI 2034R showed the highest RAA value. The order of RAA values was SKI 2034R > CDDP > SKI 2032R > SKI 2033R > SKI 2030R > SKI 2029R > 254-S. Based on the RAA order, we have recommended SKI 2034R as the most promising candidate for further development of a clinically useful platinum complex.  相似文献   
25.
143例孔源性视网膜脱离临床分析   总被引:1,自引:0,他引:1  
本文分析了143例(147眼)孔源性视网膜脱离的一般临床资料、眼部情况、手术类型及治疗结果。本组出院时136眼痊愈(92.5%);随访2月至6年的43眼中34眼痊愈(79.0%)。讨论了视网膜脱离的易发因素、术式选择、手术注意事项和预后。  相似文献   
26.
乌贼墨诱生小鼠细胞毒因子活性的检测   总被引:11,自引:2,他引:9  
用乌贼墨处理小鼠后,采集血清。经体外细胞毒实验证明:乌贼墨诱生的血清对人和鼠的肿瘤细胞株均有不同程度的杀伤作用。这一结果提示:乌贼墨可能具有诱生内源性细胞毒因子产生的活性。  相似文献   
27.
28.
6例肺癌患者接受了大剂量卡铂并自体骨髓移植治疗 ,卡铂剂量从 5 60~ 1375 mg/ m2 ,5例加用 VP~ 1630 0 mg,1例并用 MMC6mg和 VCR2 mg;主要毒性反应为白细胞、中性粒细胞、血小板减少和脱发 ( WHO毒性反应 ~ 级 )其次是贫血、皮肤粘膜出血、呕吐和可逆性肝功能损害 ,口腔粘膜溃疡及轻度发烧各 2例 ,一过性蛋白尿、室上性心动过速和便秘各 1例 ,尿素氮和肌酐未见升高 ;全部患者骨髓均获解救 ,从自体骨髓回输到骨髓造血功能重建成功平均 2 6.67( 17~ 32 )天  相似文献   
29.
PURPOSE: During clinical monitoring, vecuronium appeared to reduce the rapidly extracted auditory evoked potentials index (A-line ARX index or AAI) to some extent. A prospective and randomized study was designed to analyze this phenomenon. METHODS: Forty adult patients undergoing elective surgery were studied. After tracheal intubation, anesthesia was maintained with an end-tidal isoflurane concentration (F(ET)ISO) of 1.0% for 20 min, then a 10-mL dose of either vecuronium 0.05 mg*kg(-1), 0.1 mg*kg(-1), 0.2 mg*kg(-1) or saline was administered in a randomized, double-blind design. The AAI and bispectral index (BI(hx)) were monitored throughout the study and analyzed off-line. RESULTS: BI(hx) was unaltered after the administration of saline or vecuronium. The mean of the averaged (per patient) AAI values recorded from two minutes to ten minutes after the administration of saline or vecuronium 0.05 mg*kg(-1) did not differ significantly from the corresponding mean recorded from 15 min to 20 min after F(ET)ISO maintained 1.0% (P = 0.678, 0.169), however after the administration of vecuronium 0.1 mg*kg(-1) or 0.2 mg*kg(-1), AAI was reduced from 18.3, 18.0 to 14.8, 13.4 (P = 0.016, 0.017). CONCLUSIONS: Neuromuscular block with vecuronium reduces AAI in patients during steady state anesthesia without surgical stimuli, while BI(hx) is unaltered. The cut-off values of AAI for events should be determined according to the level of neuromuscular blockade when monitoring the depth of anesthesia/sedation.  相似文献   
30.
In this paper, we have derived some sufficient conditions for existence and uniqueness of equilibrium and global exponential stability in delayed Hopfield neural networks by using a different approach from the usually used one where the existence, uniqueness of equilibrium and stability are proved in two separate steps, rather we first prove global exponential convergence to 0 of the difference between any two solutions of the original neural networks, the existence and uniqueness of equilibrium is the direct results of this procedure. We obtain the conditions by suitable construction of Lyapunov functionals and estimation of derivates of the Lyapunov functionals by the well-known Young's inequality and Holder's inequality. The proposed conditions are related to p-norms of vector or matrix, p in [1, infinity] and thus unify and generalize some results in the literature.  相似文献   
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