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101.
This study compares the incidence of local tumor recurrence following primary excision with the CO2 laser, Nd:YAG laser (contact), Argon Beam Coagulator, or electrocautery. One hundred eight Fisher 344 rats with R3230AC mammary tumors (1.6 +/- 0.04 [SD] cm diameter) were used. All animals were randomized into groups of similar tumor size. In groups C and CS, excision was performed with a Sharplan 1060 CO2 laser (TEMoo, 25 W, continuous wave [CW], 0.2-mm spot size). Wounds in group CS were "sterilized" (0.5-mm spot size, 25 W, CW) by gently heating the wound without causing blanching or charring. In group N, a 0.4-mm contact Laser Blade and a Cooper 8000 Nd:YAG laser at 20 W CW was used. In groups SA1 and SA2, tumors were excised with the scalpel, and hemostasis and wound "sterilization" were accomplished with the Bard System 6000 Argon Beam Coagulator (ABC) at 40 W and 4 liters/min argon gas flow in SA1 and 12 liters/min in SA2. In group E, excision was accomplished at 40 W blend mode, 10 W spray mode. In group EA, excision was accomplished at 60 W cutting current, and hemostasis was achieved with the ABC. The animals were examined for evidence of recurrence for 34 days postoperatively. Mortalities were excluded from analysis. The incidence of recurrence was 11/14 (79%) in C, 6/16 (38%) in CS, 10/14 (71%) in SA1, 6/13 (46%) in SA2, 6/15 (40%) in N, 7/10 (70%) in EA, and 3/15 (20%) in E. Group E is statistically different (P less than .01) from groups EA, C, and SA1. Group C was different (P less than .01) from groups E, CS, and N. These results demonstrate an inverse relationship between tumor recurrence and local thermal effects at the surgical site. The ABC did not increase tumor recurrence. Contact YAG surgery was similar to CO2 laser excision and "sterilization." An attempt to study the influence of gas flow and pressure on local tumor recurrence and metastases should be made.  相似文献   
102.
测定左旋吡喹酮血药浓度的反相高效液相色谱法   总被引:3,自引:0,他引:3  
本文建立了测定左旋吡喹酮血药浓度的高效液相色谱分析方法.以ODS-C_(18)化学键合相(5μm)作为固定相,甲醇:水(7:3V/V)作为流动相;用吡喹酮的衍生物作为内标准品.采用紫外检测器(λ=220nm),得出检出限为2.5ng,最低检出血药浓度为0.012μg/ml血清,线性范围为0.012~1.6μg/ml血清(γ=0.999),方法回收率为93.4~97.2%.本法简便、灵敏、专一、重现性好,适用于左旋吡喹酮血药浓度测定及药物动力学研究  相似文献   
103.
摘要:目的 探究赖氨酸特异性甲基转移酶2C(lysine specific methyltransferase 2C,KMT2C)在胃癌发生发展中的 作用及机制。方法 通过 TCGA 数据库分析 KMT2C在胃癌与癌旁的表达差异。采用 Western blot检测 KMT2C在胃 癌与癌旁临床样本中的表达差异。通过 Kaplan-Meier Plotter数据库分析 KMT2C 对胃癌患者预后的影响。采用细胞 实验(克隆形成、EdU 及 CCK-8检测)及皮下瘤负荷模型检测 KMT2C 在体内外对胃癌细胞增殖能力的影响。结果 KMT2C在胃癌中高表达。胃癌患者中 KMT2C高表达组相对于 KMT2C低表达组预后较差。敲减 KMT2C在体内外 均有抑制胃癌 细 胞 增 殖 的 作 用。基 因 集 富 集 分 析 (GSEA)发 现 KMT2C 影 响 c-Myc信 号 通 路。敲 减 KMT2C 后, H3K4me1蛋白表达水平降低,同时,CDK4的 mRNA 与蛋白表达水平降低。KMT2C与c-Myc核内结合促进了c-Myc 与 CDK4的启动子区域的结合。结论 KMT2C通过影响c-Myc/CDK4信号通路促进胃癌细胞增殖。  相似文献   
104.
目的 探讨血液肿瘤患者肛拭子耐碳青霉烯类肠杆菌(CRE)主动筛查情况及继发血流感染的影响因素。方法 选取2020年9月—2022年6月在苏州大学附属第一医院治疗的血液肿瘤患者1 258例,所有患者行肛拭子CRE主动筛查,分析CRE定植分布、血流感染情况及其影响因素。结果 共检出CRE 109株,以肺炎克雷伯菌、大肠埃希菌为主;10例患者发生CRE血流感染;CRE酶型分布中,主要以NDM、KPC为主;有中性粒细胞缺乏患者CRE定植发生率高于无中性粒细胞缺乏患者(P<0.05);有消化道症状患者CRE定植发生率高于无消化道症状患者(P<0.05);多因素逐步Logistic回归分析结果显示,中性粒细胞缺乏■是血液肿瘤患者CRE定植发生的影响因素(P<0.05)。不同性别、年龄、疾病类型及有无中性粒细胞缺乏、消化道症状患者的血流感染发生率比较,差异均无统计学意义(P>0.05)。结论 血液肿瘤患者肛拭子CRE主动筛查能有效筛出CRE感染者,CRE定植感染与中性粒细胞缺乏有关,临床应加以重视。  相似文献   
105.
胎儿筛骨的形态学研究   总被引:1,自引:0,他引:1  
本文从组织学角度,研究胎儿筛骨的形态学变化以及水平板、纸板和筛凹的发育特点。结果表明:筛骨整体(在冠状位)呈等腰梯形,即纸板为梯形的两边;胎儿期的纸板在水平切面上呈向外凹的骨板,至出生时呈轻微的“S”形弯曲;胚胎第24周后,水平板的外侧部分逐渐形成筛凹,并随筛窦的气化而变薄,形成筛窦的顶部。上述结果提示:出生时其眶内侧壁(主要为纸板)结构不呈矢状平面,且与水平板间的角度(斜度)随胎龄增长而增大(P<0.01);筛骨水平板则由内侧部分的筛板和外侧部分的筛凹组成。  相似文献   
106.
This study made a histological comparison (light microscope and transmission electron microscope) between vascularized bone graft (VBG) and non-vascularized bone graft (NVBG) in mandible of dog.The study showed:the healing process of VBG was the same as that of bone fracture.The "creeping substitution" process of NVBG was imbued with the inflammation induced by dead bone.There was no significat difference on the bone union between VBG and NVBG perhaps for the recipient region was better vascularized.  相似文献   
107.
目的:探讨冠心病(CHD)患者血浆同型半胱氨酸(HCY)水平与冠脉病变程度及C-反应蛋白(CRP)、血脂水平的关系。方法:检测102例CHD患者和27例正常对照人群的血浆HCY和CRP、甘油三酯(TG)、总胆固醇(TC)和脂蛋白(a)[LP(a)]水平,并进行比较及相关性分析。结果:CHD组血浆HCY以及CRP、TG、TC、LP(a)水平显著高于正常对照组;CHD组血浆HCY水平与CRP、TG、TC、LP(a)无明显相关性(P>0.05),血浆HCY、CRP、TG、TC、LP(a)水平随着冠脉病变支数增加而增高,呈显著正相关。结论:高血浆HCY是CHD的独立危险因素,对CHD的预防和诊断具有一定的临床意义。  相似文献   
108.
Cyclin alterations in giant cell tumor of bone.   总被引:3,自引:0,他引:3  
Cyclins play an important role in regulating the passage of dividing cells through critical checkpoints in the cell cycle. Because alterations of several cyclins, especially cyclin D1, have been implicated in the development of many human neoplasms, we examined 32 cases of giant cell tumor of long bones for cyclin D1 gene amplification and protein overexpression using differential polymerase chain reaction and immunohistochemistry, respectively. In addition, the expression of cyclin D3, cyclin B1, and the proliferation-associated antigen Ki-67 (MIB-1) was assessed immunohistochemically. Low-level cyclin D1 gene amplification was detected in 61% of giant cell tumor cases. All tumors showed cyclin D1, cyclin D3, cyclin B1, and Ki-67 (MIB-1) staining; however, the distribution was very characteristic. Cyclin D1 protein expression was seen predominantly in the nuclei of the giant cells, with occasional mononuclear cells staining. There was no correlation between cyclin D1 gene amplification and protein overexpression. Cyclin D3 staining showed a similar distribution, with 88% of cases showing protein overexpression. Cyclin D1 and/or D3 staining in the giant cells was never associated with staining for either cyclin B1 or Ki-67 (MIB-1), as the expression of the latter two proteins was restricted to the mononuclear cells. Cyclin B1 overexpression was seen in 44% of cases. Ki-67 (MIB-1) staining was present in all cases, and between 10 to 50% of the mononuclear cells were positive. These results suggest that alterations in cyclin D1 and/or D3 might play a role in the pathogenesis of giant cell tumor of bone.  相似文献   
109.
本文采用液氮浅低温冷冻疗法治疗50例急性冠周炎患者,取得了良好临床效果,并于冷疗前后对血及唾液中IgG、IgA、IgM和血中C3及淋巴细胞转化率进行了免疫状态研究。实验结果表明,冷疗后系列免疫指标明显增高。故认为冷冻治疗冠周炎的主要机理是提高机体的免疫功能。  相似文献   
110.
The Charcot-Mane-Tooth disease type 1A (CMTlA) phenotype is most often associated with a 1.5 megabase (mb), tandem duplication of chromosome 17 band p12 (17˜12). The prevailing hypothesis is that the demyelinating neuropathy results from a dosage effect of the peripheral myelin protein gene PMP22 which is included within this duplication. We present a patient with clinical and electrophysiological features ofCMTlA in whom an extra PMP22 gene resulted from a rare unbalanced translocation of 17p to the X chromosome. This finding further supports the hypothesis of gene dosage as the basis for CMTlA. More-over, this case highlights the importance of fluorescence in siiu hybridization (FISH) as an alternative molecular technique in the diagnosis of CMTlA.  相似文献   
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