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本文分析了460例胃癌胃粘膜活检资料,结果:男:女为2.36:1:51~60岁年龄组发病率最岛(37.17%);发生部位以胃窦部最多见,占46.74%;组织学分类以低分化腺癌最多,占51 52%;在伴随病变中,畅化生的检出率为21.74%,胃腺囊为35%,胃粘膜上皮异型增生为32.61%。本组材料提示,不完全性大肠型肠化生、异型胃腺囊及胃粘膜中度以上异型增生与胃癌有密切关系。  相似文献   
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目的 检测并比较心肌梗死急性期不同时间点,β2自身抗体阳性组与阴性组,患者血清中Fas/APO-1水平差异,了解β2自身抗体对Fas/APO-1的影响。方法 41例急性心肌梗死患者,分别于发病24h、7天、2~4周时取血,采用ELISA的方法,检测血清中β2自身抗体的阳性率以及Fas/APO-1的水平;另外取34位性别、年龄匹配的健康人的血同法检测Fas/APO-1作为对照。结果心肌梗死急性期Fas/APO-1的水平均高于对照组(P〈0.05),以梗死后24hFas/APO-1的水平为最高;心肌梗死急性期不同时间点,β2自身抗体阳性组Fas/APO-1的水平均高于阴性组,但两组的结果差异无显著性(P〉0.05)。结论 血清Fas/APO-1水平可以在一定程度上反映心肌细胞凋亡的变化趋势,β2自身抗体对Fas/APO-1的确切影响,有待更大规模的实验来证实。  相似文献   
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OBJECTIVES: Diagnostic accuracy of the ThinPrep process (Cytyc, Boxborough, MA) was compared with that of conventional (smear) cytopreparation for fine-needle aspiration (FNA) of head and neck masses. METHODS: In a prospective, randomized, single-blinded study, 209 patients served as their own controls and underwent 236 FNAs using ThinPrep and conventional (smear) cytopreparatory techniques. RESULTS: ThinPrep produced less air-drying artifact and less mechanical distortion than the conventional method. The conventional technique was diagnostic in 63% of samples; the ThinPrep technique was diagnostic in 55% of samples. When all results were combined, pathologists subjectively preferred the conventional technique but accepted use of ThinPrep as the only cytopreparatory technique for most head and neck masses. CONCLUSIONS: For adequately experienced cytopathologists, ThinPrep is acceptable for FNA of salivary masses, neck cysts, metastatic lymph nodes, and thyroid lesions. Conventional smear technique should be used for FNA of nonmetastatic lymphoid lesions. Use of ThinPrep can complement use of the conventional (smear) cytopreparatory technique when aspirate is nondiagnostic or bloody, when the patient has a blood-borne infectious disease, when the clinician is inexperienced, or when aspirate has entered the syringe.  相似文献   
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A design technique (Control of Uncertain Systems with Bounded Inputs, Tarbouriech S, Garcia G, (Eds), Lecture Notes in Control and Information Sciences, vol. 227 , Springer: Berlin, 1997; 173–186) recently proposed for stabilization of a linear system with rate‐limited actuators is utilized to design feedback laws that cause the system output to track a desired command signal. This design technique combines two design techniques recently developed for linear systems with position limited actuators, piecewise‐linear LQ control (Automatica, 1994; 30 : 403–416) and low‐and‐high gain feedback (IEEE Trans. Automat. Control, 1996; 41 : 368–378), and hence takes advantage of both design techniques, while avoiding their disadvantages. In the case that only the output is available for feedback, the performance of the state feedback law is preserved by the use of a fast observer. An open‐loop exponentially unstable fighter aircraft is used to demonstrate the effectiveness of the proposed control design method. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
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OBJECTIVE: To investigate the effects of intraperitoneal CO2 insufflation on the hemodynamics, oxygen consumption (VO2) and carbon dioxide production (VCO2) during intravenous anesthesia with propofol in combination with epidural block. METHODS: Intratracheal intubation was performed after rapid induction of anesthesia and mechanical ventilation was given. Maintenance of anesthesia was achieved using continuous intravenous propofol infusion (2 mg/kg/h) ?N2O inhalation and intermittent epidural administration. Indices of hemodynamics and respiratory function were collected 5 min before induction, 1 min before CO2 insufflation, and 5, 10, 20, 30, 40, 50, 60 min after the start of insufflation and 5 min after the termination of insufflation. RESULTS: The mean arterial pressure (MAP), heart rate (HR), end-tidal PCO2 (P(ET)CO2), VO2 and VCO2 1 min before insufflation were markedly reduced(P<0.01), compared with those recorded before induction. MAP and HR did not undergo any conspicuous changes during CO2 insufflation and 5 min after insufflation termination. Compared with that 1 min before insufflation, PETCO2 was significantly increased 20 min after the start of insufflation (P<0.01), and subsequently carried on the increase though of a lesser scale. VO2 and VCO2 gradually rose after the start of insufflation, and VO2 presented a significantly elevation (P<0.01) 10 min after the insufflation while VCO2 did not show this marked increase(P<0.05) till 20 min after the insufflation in comparison with the levels before insufflation. Subsequently, VO2 continued to rise and VCO2 also retained the increase but of smaller magnitude. CONCLUSION: Intravenous propofol anesthesia combined with epidural block assisted by well-managed excessive ventilation before insufflation can alleviate the adverse effects of CO2 insufflation on respiratory and circulatory systems.  相似文献   
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Wall-eyed bilateral internuclear ophthalmoplegia (WEBINO) is a rarely reported syndrome. There is dispute about whether WEBINO is caused by a pontine or a midbrain lesion and whether the medial rectus subnuclei are implicated. In a study of the clinical and imaging features of four patients with WEBINO, we found that that three of four lesions involved the midbrain but not necessarily the medial rectus subnuclei.  相似文献   
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