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61.
盛磊  王辰涯 《中国美容医学》2014,(19):225-226,209
文章通过对某常减压装置的换热网络设计时的分析,提出最佳的网络优化方案。运用流程模拟软件在保证各侧线产品质量和收率的情况,通过对塔取热比例的优化,以尽可能提高换热终温;同时在不影响装置换热终温的前提下,尽可能的产生1.0 MPa蒸汽,大幅降低其他冷公用工程消耗,从而显著的降低装置的能耗。  相似文献   
62.
63.
目的:探讨高危肾盂癌患者的治疗方法。方法:自2009年7月~2012年12月对14例高龄且伴有严重并发症的肾盂癌患者行经腹膜后途径腹腔镜下肾脏+中上段输尿管切除术,术后正规膀胱灌注表柔比星注射液,以预防再发膀胱癌,并定期进行影像学及膀胱镜检查。结果:14例手术全部成功,手术时间63~105min,平均78.3min。术后24~48小时恢复饮食,5~9天出院。术后病理检查2例为鳞状细胞癌,12例为尿路上皮细胞癌;其中2例为浸润性肾盂癌伴肾门处淋巴结转移。术后13例得到随访,1例失访;随访8~36个月,平均21.4个月。1例术后13个月死于肺部转移,2例术后21个月因心肺疾病死亡;2例术后再发膀胱癌,行根治性全膀胱切除。结论:对于高危肾盂癌患者,简化手术,腹腔镜下切除肾脏+中上段输尿管,术后配合正规膀胱灌注化疗是一种有效安全的治疗方法。  相似文献   
64.

Purpose

To determine the role of dynamic cervical implant (DCI) replacement for single-level degenerative cervical disc disease in Chinese patients.

Methods

Thirty patients with single-level degenerative cervical disc disease were prospectively enrolled between April 2010 and August 2010 (12 women, 18 men; mean age 56.5 years). All patients underwent anterior cervical decompression, DCI replacement, clinical and radiological assessments preoperatively and at 1, 6, 12, and 24 months postoperatively, and Japanese Orthopaedic Association (JOA), Visual Analogue Scale (VAS), Neck Disability Index (NDI), and Short Form 36 (SF-36) scores. Lateral neutral radiographs provided the intervertebral space height. Lateral dynamic radiographs were taken to measure the range of motion (ROM) of the cervical spine and functional spinal unit (FSU) of the treated segment. We compared the amount of motion of the adjacent vertebral endplate and the intrinsic motion of the implant and calculated a correlation analysis.

Results

DCI showed good clinical and radiographic outcomes. At the final follow-up, JOA, VAS, NDI, and SF-36 average scores improved significantly. The intervertebral space height increased slightly after operation and was maintained during follow up. The ROM of the cervical spine and FSU decreased at early follow-up, but recovered to the preoperative level within 1–2 years. There was a high index of linear correlation between the motion of the adjacent vertebral endplate and the intrinsic motion of the implant.

Conclusions

DCI provided elastic dynamic stability for the targeted segment, and restored and sustained intervertebral space height and ROM of the cervical spine.  相似文献   
65.
Multifocal liposarcoma with different histological types is rare, especially that originating from the mesentery. We herein report a case of primary myxoid liposarcoma from the sigmoid mesocolon that was accompanied with well-differentiated liposarcomas in the pelvis. The location, the fat signal and the relationship with adjacent organs of the liposarcomas were well shown in the axial, coronal and sagittal dimensions of MRI, giving a comprehensive and specific image before surgery. To alleviate the patient’s symptoms and mental stress, a laparotomy was performed. The tumors were all completely excised with macroscopic free margins. The final histopathological report showed that the tumor in the sigmoid mesocolon was a pure myxoid liposarcoma, while the pelvic tumors were spindle cell liposarcomas, a special type of well-differentiated liposarcoma. According to the AJCC staging system, they were all stage IIB. No further adjuvant therapy was performed. Close follow-up after the surgery has been performed, and the patient has remained healthy without any evidence of recurrence or metastasis for 17 months after the surgery.  相似文献   
66.
目的了解胃肠手术患者术后120h内的下床活动水平并分析其影响因素。方法采用一般资料调查表、一般自我效能感量表、医学焦虑抑郁量表、促进和阻碍因素问卷及下床活动水平等级评分方法 ,对144例胃肠手术患者进行调查。结果胃肠手术患者术后120h内的平均下床活动水平等级评分为6.5,处于中水平活动状态。不同手术部位、输液总量、尿管留置时间,是否使用尿壶、是否肠内营养的患者,其术后下床活动水平比较,差异有统计学意义(P0.05,P0.01);自我效能、肠内营养等医疗限制及尿壶的使用是影响患者术后下床活动水平的主要因素(P0.05,P0.01)。结论胃肠手术患者术后120h内下床活动现状不理想,应加强健康教育,增强患者的自我效能,为肠内营养患者制定下床活动计划,鼓励患者尿管拔出后下床排尿,以促进患者康复。  相似文献   
67.
68.
Photoacoustic tomography (PAT) is an emerging non-invasive imaging technique with great potential for a wide range of biomedical imaging applications. However, the conventional PAT reconstruction algorithms often provide distorted images with strong artifacts in cases when the signals are collected from few measurements or over an aperture that does not enclose the object. In this work, we present a total-variation-minimization (TVM) enhanced iterative reconstruction algorithm that can provide excellent photoacoustic image reconstruction from few-detector and limited-angle data. The enhancement is confirmed and evaluated using several phantom experiments.  相似文献   
69.
The blood-testis barrier (BTB) is found between adjacent Sertoli cells in the testis where it creates a unique microenvironment for the development and maturation of meiotic and postmeiotic germ cells in seminiferous tubes. It is a compound proteinous structure, composed of several types of cell junctions including tight junctions (TJs), adhesion junctions and gap junctions (GJs). Some of the junctional proteins function as structural proteins of BTB and some have regulatory roles. The deletion or functional silencing of genes encoding these proteins may disrupt the BTB, which may cause immunological or other damages to meiotic and postmeiotic cells and ultimately lead to spermatogenic arrest and infertility. In this review, we will summarize the findings on the BTB structure and function from genetically-modified mouse models and discuss the future perspectives.  相似文献   
70.
Crouzon syndrome is an autosomal-dominant disorder that causes premature fusion of the cranial suture. Crouzon, Pfeiffer, and Apert syndromes are caused by mutations in the extracellular, third immunoglobulin-like domain, and adjacent linker regions (exons IIIa and IIIc) of the fibroblast growth factor receptor 2 (FGFR2) gene. We screened 12 Crouzon syndrome patients for mutations in exons IIIa and IIIc of the FGFR2 gene by polymerase chain reaction (PCR) and direct sequencing. Mutations were detected in nine of 12 patients at amino acid positions 278, 281, 289, 342, and 354. More than half of the studied Crouzon patients carried a mutation resulting in either the loss or gain of a cysteine residue. A novel missense Ser354Phe substitution at exon IIIc of the human FGFR2 gene was found. According to our results, sequencing analysis of IgIII domain of the FGFR2 gene can lead to a genetic diagnosis of Crouzon syndrome.  相似文献   
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