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11.
一种新的正交参数选优法及其在非线性回归分析中的应用   总被引:2,自引:0,他引:2  
非线性回归分析是工程中经常采用的一种用来估计数学模型参数的方法,该方法能否顺利运用与参数初始值的选择有极大关系。本研究提出一种新的正交参数选优法——阻尼正交表法,它不仅可以保证非线性回归分析算法的顺利收敛,而且能够显著提高后者的收敛速度,进而极大改善非线性回归分析算法的应用性能。本研究的数值试验及心肌造影超声心动图定量分析应用实例表明,作为对传统正交参数选优法的一种改进,阻尼正交表法在科学与工程计算或信号与信息处理领域有着很好的应用前景。  相似文献   
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Eight cases of malignant and 12 0f benign Bren- ner tumor are reported, patient ages ranged 31 69 and 39-53 years. The malignant tumor was bilateral in 6 0f 8 cases, and the benign in l of 12. The greatest diameter of the malignant tumors averaged around 11 cm, and the benign 10. Six of the malignant Brenner tumor patients died, one was lost to follow up, and one survived for 10 years. Pathologic and microscopic findings were pre- sented in some detail. Based on the analysis of the association between the histologic features and type of Mullerian epithelium, we believe that the so called Brenner tumor is in effect a tumor arising from the Mullerian epithelium with a tendency to differentiate into vaginocervical type epithelium.  相似文献   
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目的了解糖尿病(DM)患者与血清肿瘤坏死因子的关系及意义.方法采用放射免疫法对75例患者组和43例正常组进行了同步检测TNFα的含量.结果患者组血清TNFα明显高于正常组并与糖化血红蛋呈正相关,且与胰岛素敏感指标呈负相关,而DM患者抗谷氨酸脱羧酶抗体阳性组的血清TNFα水平较阴性组有明显增高.结论糖尿病患者血清TNFα水平的异常增高,可推测与长期的糖代谢紊乱、自身免疫性的胰岛损伤及胰岛素抵抗有关.  相似文献   
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We present a case of benign osteoblastoma of the occipital bone. Benign osteoblastoma is an uncommon primary bone tumor, which usually involves the vertebrae and the long bones. This tumor rarely develops in the calvaria, showing a preference for the temporal and frontal bones when it does. To the best of our knowledge, this case is only the eighth reported case of benign osteoblastoma confined to the occipital bone. A 20‐year‐old male presented with a mild tender mass lesion of the occipital area, just below the lambda. Plain X‐ray films and CT scans demonstrated an osteolytic mass surrounded by the sclerotic rim within the diploic space. MRI proved to be effective for the evaluation of the intracranial and intraosseous extensions of the tumor. However, it was very difficult to formulate a differential diagnosis against other osteoblastic tumors, or osteoid osteoma, in view of its radiological appearance. The final diagnosis was obtained by careful consideration of the histopathological characteristics of the tumor combined with its clinical and radiological features. Although generally regarded as benign, a complete resection is preferred over conventional curettage as this can guard against possible recurrence and malignant transformation.  相似文献   
16.
男性慢性胃炎患者人格特征初探   总被引:4,自引:0,他引:4  
本文采用卡氏十六种人格因素量表,对纤维胃十二肠镜和活体组织病理检查确诊,剔除可能影响调查的疾患之后的56例慢性胃炎患者做了测查,结果与中国男性成人常模对照,提示男性慢性胃炎患者的主要人格特征有:严谨、保守、忧郁、紧张、顺从、依赖、有焦虑倾向,非内向个性,不属于心理不健康人群,而与消化性溃疡个性特征有所不同,但是,矫治其人格缺损及属必要。  相似文献   
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BACKGROUND CONTEXT: Posterior lumbar interbody fusion (PLIF) is a popular method of arthrodesis for surgical treatment of instabilities and degenerative conditions of the spine. With the introduction of threaded titanium cage devices, surgeons began performing PLIF procedures using these cages as stand-alone devices. Complications have been reported, however, including pseudarthrosis with persistent pain. Outcomes after revision surgical treatment for these patients with failed PLIF are not known. PURPOSE: To prospectively evaluate clinical outcomes of revision fusion surgery in patients who previously underwent posterior lumbar interbody fusion with stand-alone metallic cages resulting in pseudarthrosis. STUDY DESIGN/SETTING: Prospective case series. METHODS: Nineteen patients referred to the senior author were evaluated and diagnosed with pseudoarthrosis having previously undergone a PLIF procedure with stand-alone metallic cages. History, physical exam, and imaging studies were performed preoperatively and postoperatively. All underwent revision posterolateral fusion with iliac crest graft and pedicle screw instrumentation. Patient demographics, SF-36, and Oswestry Disability Index (ODI) data were collected prior to surgery and two years postoperatively. RESULTS: Patients undergoing revision fusion surgery were found to have had extensive facetectomies and pseudarthrosis intraoperatively. Outcomes data was collected on eighteen of nineteen patients (95%). Mean clinical follow up was 3.2 years (range 2.5-3.5 years). Seventeen patients (94%) achieved a solid fusion. Improvement was noted in seven of eight SF-36 sub-categories, but was significant only in two (Physical Function and Role Emotional). There was no significant difference in ODI scores. CONCLUSIONS: Pseudarthrosis should be considered in the differential diagnosis if severe symptoms persist in patients who undergo PLIF with stand-alone metallic cages. Successful revision fusion did not always correlate with improved clinical outcomes in these challenging patients undergoing further surgery. Performing PLIF using stand-alone metallic cages, especially after total resection of the facet joints, is not advocated unless supplemental instrumentation is utilized.  相似文献   
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BACKGROUND: The tuberous breast presents a problem for which many surgical solutions have been described. Current teaching describes how the tuberous breast deformity is the result of skin shortage as well as herniation of breast tissue through the nipple-areola complex. However, through careful clinical observation we now believe that the only abnormality present is herniation of breast tissue through the nipple-areola complex. METHODS: Using this principle, we have refined a one-stage surgical procedure that can be used to correct any type of tuberous breast deformity. Since 2001 we have performed our technique on a series of 13 tuberous breasts of widely varying appearances in eight patients (age 17-24 years) with a follow up varying between 3 and 56 months. Our new understanding of the tuberous breast deformity has also made it possible to develop an objective, reproducible method for defining the tuberous breast based on the degree of areola herniation. RESULTS: All patients reported high levels of satisfaction with the procedure. Assessment of the results by an independent panel of attending surgeons showed all results to be good/excellent. Moreover, the results have improved with time and no revisions have been needed. Our method of defining the tuberous breast (based on the ratio of areola herniation:areola diameter) enabled us to identify a cut-off to decide (objectively) when a breast was tuberous. This allowed us to anticipate when an areola reduction/tightening procedure would be necessary to avoid a 'double-bubble' deformity. CONCLUSION: We propose a one-stage surgical procedure which is applicable to all degrees of tuberous breast deformity. The results appear to confirm our theory that the only abnormality present in the tuberous breast is herniation of breast tissue through the nipple-areola complex. In patients with small breasts and a tuberous deformity, correction of the herniation changes the tuberous breast into a simple hypoplastic breast. The volume deficit can then be corrected by augmentation (if desired by the patient). In patients with sufficient breast volume, correction of the herniation alone will correct the deformity.  相似文献   
20.
医源性桡神经损伤46例分析   总被引:1,自引:0,他引:1  
目的阐述医源性桡神经损伤的伤因、治疗和预防措施。方法分析1991年~2003年间收治的46例医源性桡神经损伤的病例。结果伤因分为上肢手术误伤,肱骨干和桡骨上端闭合性骨折复位手法不当,头静脉穿刺致桡神经浅支损伤。本组21例保守治疗,22例手术治疗,3例行肌腱转位功能重建。结论手术误伤是医源性桡神经损伤的首要原因;临床医生丰富的解剖知识和细致、轻柔的操作是预防医源性桡神经损伤的关键。  相似文献   
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