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81.
PURPOSE: Evaluation of the healing and persistence of a meshed composite skin graft applied without immunosuppression. METHODS: The contraction of wounds grafted with 9:1 split-thickness autograft/1.5:1 allodermal mesh composite skin grafts (auto/allo MCSGs) was investigated. No immunosuppressive agent was applied. Male ACI rats and female Lewis rats reciprocally served as allodermis graft donors and recipients. Autograft/dermal autograft and allograft/dermal allograft MCSGs were the controls. RESULTS:AT 3 months after grafting, when epithelized auto/allo MCSG wounds were measured by computerized morphometric analysis, the silver nylon (SN) dressing group displayed less contraction than the Vaseline (petroleum jelly) dressing group (p < 0.003), and direct current treatment (SNDC) was more effective than SN (p < 0.005). The histologic structures of the hair follicles appear to confine the rejection process to the allogeneic follicles of the graft. The focal nature of the rejection process and the relatively low antigenicity of the dermal matrix allowed the survival of the allodermis layer. Although direct current significantly enhanced MCSG healing, SN and SNDC were not the immunosuppressive agents that were confirmed. CONCLUSION: This type of MCSG can heal without immunosuppressive treatment.  相似文献   
82.
眼灌注压对人视乳头微循环的影响   总被引:4,自引:0,他引:4  
目的 了解眼外负压吸引诱导的眼灌注压改变的条件下,正常人、原发性开角性青光眼(POAG)患者和正常眼压性青光眼患者(NTG)的视乳头微循环的变化,探讨视乳头局部自身调节的幅度。方法正常人8例,POAG患者10例和NTG患者7例,采用眼外负压杯吸引诱导眼压升高,负压增加的幅度为30s50mmHg,同时测量眼压。采用HRF测量视乳头处血流量。将基础状态下视乳头血流值作为基础值,当眼压升高到30mmHg和40mmHg时,分别测量这两点视乳头微循环的血流值,在40mmHg后解除负压吸引,测量负压吸引解除后1min、5min时视乳头微循环的血流值。结果 三组视乳头的基础血流量无明显差异。当眼压升高到30mmHg时,正常组的血流量仍维持稳定,但POAG组和NTG组明显下降,POAG组下降幅度超过25%,NTG组下降幅度超过45%。当眼压升高到40mmHg,正常组视乳头血流量也出现明显下降,其中0NHF下降约30%,POAG组和NTG组下降更明显,POAG组下降幅度超过50%,NTG组下降幅度超过65%。在解除负压吸引后1min,正常组血流量增加的幅度约为31%,POAG组增加约19%,NTG组无明显增加。在负压解除后5min,三组视乳头血流基本恢复到基础状态。结论 正常组视乳头微循环有一定范围的自身调节幅度,可以耐受眼灌注压一定程度的改变,POAG组和NTG组自身调节能力均有不同程度的损害。  相似文献   
83.
BACKGROUND AND PURPOSE: Survivin, an inhibitor of apoptosis, is expressed in fetal tissues but undetectable in normal adult tissues. It is also expressed in most common human cancers. This study evaluated the expression of survivin in breast cancers. METHODS: A monoclonal anti-survivin antibody B1 was generated. Immunohistochemical staining was performed in 226 paraffin sections of primary breast cancers and correlated with the patients' clinicopathological characteristics. RESULTS: Survivin was expressed in the cytoplasm of tumor cells in 59.3% of breast cancers. Expression of survivin was associated with high histologic grade (p = 0.027), high mitotic count (p = 0.014), positive p53 immunostaining (p = 0.012), neu overexpression (p = 0.018), and with bcl-2 (p = 0.001) and bak (p < 0.001) expression. No correlation was found between survivin expression and age, tumor size, estrogen receptor, progesterone receptor or Bax expression. Survivin expression was not significantly associated with overall or disease-free survival. CONCLUSIONS: Survivin expression is correlated with high histologic grade, high mitotic count, p53 overexpression, and bcl-2 expression in breast cancer. It does not have significance as a marker in predicting overall or disease-free survival.  相似文献   
84.
Neuroleptic malignant syndrome (NMS) is a potentially lethal adverse reaction to neuroleptics, which is characterized by hyperthermia, extrapyramidal symptoms, altered consciousness and autonomic dysfunction. Although NMS is most commonly induced by the high-potency neuroleptics, its development has also been associated with the use of non-neuroleptic agents that block central dopamine pathways. A 68-year-old man with generalized anxiety disorder and depressive symptoms presented at the emergency department (ED) with high fever, tremor, muscle rigidity, rhabdomyolysis and altered mental status. NMS was considered to have been caused by the recent addition and subsequent dose increase in his treatment regimen of venlafaxine, a serotonin norepinephrine reuptake inhibitor. He was successfully treated with bromocriptine, lorazepam, and fluid hydration in the ED and intensive care unit.  相似文献   
85.
Myositis ossificans originating from the chest wall is extremely rare. We report a case of myositis ossificans occurring in a young woman with progressive painful swelling in the chest wall. Preoperative examination suggested a malignant neoplasm originating from soft tissue. Although rare, myositis ossificans is one of the potential causes of painful swelling in the chest wall, and can be mistaken for a malignant neoplasm.  相似文献   
86.
A 58-yr-old male with a history of hepatitis C virus infection, presented with a 2-mo history of intractable left upper abdominal pain. He had fallen from a ladder 2 yr previously, landing on his left side. Abdominal computed tomography identified a large cystic mass in the spleen. The patient was brought to the operating room with a presumptive diagnosis of symptomatic, post-traumatic, false cyst of the spleen. Instead, at surgery, a splenic mass with dense adhesions to the diaphragm and stomach was found. On final histological analysis, it was diagnosed to be a large B-cell lymphoma. Despite its rarity, gastroenterologists and surgeons should be aware of large B-cell lymphoma when encountering cystic lesions of the spleen, because the management of benign cystic disease is usually nonsurgical.  相似文献   
87.
Medial cortex strain distribution during noncemented total hip arthroplasty   总被引:2,自引:0,他引:2  
Intraoperative proximal femur fractures are a significant concern during noncemented total hip arthroplasty. The current study was performed to investigate the hypothesis that broaching the femur and inserting the stem without using mallet applied impact loads will reduce the risk of intraoperative fracture. Rosette strain gauges were applied to the medial and anteromedial cortex of six human anatomic specimen femurs to compare the strain distribution for broaching and stem insertion. Eight additional femurs were used to compare the strain distribution for stem insertion using impact loading and constant rate stem insertion. For the impact loading stem insertions, the soft tissues surrounding the femur were modeled. Constant rate stem insertions were performed using a mechanical testing machine. The largest strains measured at the medial and anteromedial sites primarily were aligned with the femur hoop axis. The largest strain magnitude, orientation, and sign (tensile or compressive) varied widely among femurs. The stem insertion strains were significantly larger than the broaching strains (two-way analysis of variance with replication). The impact stem insertion strains were not significantly different from the constant rate stem insertion strains. The results indicate that the femur geometry and material properties have a greater influence on the strain distribution than does the implantation technique.  相似文献   
88.
BackgroundTalus fractures are rare in children but can lead to severe outcomes if untreated. The Ilizarov external fixator has been used in the treatment of a variety of lower extremity pathologies. The purpose of this study was to investigate the clinical outcomes of talus body fractures treated with the Ilizarov external fixator.Case PresentationFour male pediatric patients (age range, 5–11 years) with talus body fractures who were treated by open reduction and internal fixation combined with Ilizarov external fixator between November 2015 and April 2016 were reviewed. Mean follow‐up period was 4 years (range, 4–5). Clinical outcome was evaluated using the clinical rating scale of the American Orthopaedic Foot and Ankle Society (AOFAS). All four patients achieved good to excellent results at the last follow‐up. None of the patients developed avascular necrosis. One patient developed automatic fusion of tibiotalar joint.ConclusionUse of the Ilizarov external fixator to gain early range of motion is a valuable option for treatment of talus body fractures in children.  相似文献   
89.

目的:总结新型冠状病毒(SARS-CoV-2)感染相关急性黄斑区神经视网膜病变(AMN)的神经眼科特征。

方法:纳入2022-12-27/2023-02-01就诊于西安市第一医院(西北大学附属第一医院)神经眼科并经相关检查确诊为AMN的患者8例(6例女性,2例男性)共14眼纳入本次研究。所有患者病前均有SARS-CoV-2感染史。收集患者的临床资料。纳入最佳矫正视力(BCVA)、非接触间接眼压测定、眼底彩色照相、近红外成像(IR)、频域光学相干断层扫描(SD-OCT)、OCT血流成像(OCTA)、眼底荧光素血管造影(FFA)、吲哚菁绿血管造影(ICGA)、视野、视觉诱发电位(VEP)和视网膜电流图(ERG)检查结果。对纳入患者的神经眼科特征进行分析总结。

结果:纳入的8例患者年龄20-43(平均30±6.63)岁。病前3-11(平均5±3.51)d有SARS-CoV-2感染史,8例患者中有6例在感染SARS-CoV-2的5 d内出现视觉症状。患者的临床表现为视力下降或视物遮挡感; 纳入患者的视力0.08-1.0; 视野缺损表现为中心、旁中心暗点或合并周边暗点。VEP可见P100或P2峰时延迟; ERG提示视网膜感光细胞 功能受损。在疾病早期,SARS-CoV-2感染相关AMN患者可能存在视力、视野和视网膜外层病变大小及形状可能不匹配的情况,并发现视力越低,VEP峰时越迟。

结论:除眼底多模影像,SARS-CoV-2感染相关AMN的神经眼科特征需要临床医师关注,视功能及电生理可以辅助临床更加全面评估患者及判断预后。  相似文献   

90.
目的 比较腓骨髓内钉与切开复位钉板系统治疗腓骨远端骨折的疗效.方法 回顾性分析2017年10月至2019年10月于锦州医科大学附属第一医院采用手术治疗腓骨骨折的患者,按照纳入、排除标准筛选病例,最终A组髓内钉组25例纳入研究、B组钉板内固定组35例纳入研究.比较两组入院至行腓骨手术的时间,手术时长,腓骨术口总长度,AO...  相似文献   
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