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101.
102.
目的 研究胃癌增殖细胞核抗原(proliferating cell nuclear antigen,PCNA)表达与腹腔灌洗液端粒酶活性及腹膜转移的相关性,并比较腹腔灌洗液中端粒酶活性和细胞学检测游离癌细胞预测腹膜转移的应用价值。方法 应用免疫组化SP法检测60例胃癌患者胃癌组织中PCNA表达,PCR—TRAP-ELISA法检测腹腔灌洗液中端粒酶活性,同时行腹腔灌洗液脱落细胞学(peritoneal lavage cytology.PLC)检测;并分析其与相关临床病理因素的关系。结果 胃癌患者腹腔灌洗液中端粒酶活性的阳性率为41.7%;与浆膜侵犯、组织学类型、浸润深度、浆膜受累面积及腹膜转移密切相关,并随着浸润深度及浆膜受累面积的增加而升高(P〈0.05)。PLC检测阳性率为25.0%;在伴肉眼可见腹膜转移灶(P1-3)者明显增高,也随着浸润深度及浆膜受累面积的增加而升高。两种方法检测的阳性率总体上差异无统计学意义。但在未分化型癌、pT1、伴肉眼可见腹膜转移灶(P1-3)者端粒酶活性阳性率明显高于PLC。PCNA增殖指数(PI)在腹腔灌洗液端粒酶活性表达阳性者明显高于表达阴性者,伴肉眼可见腹膜转移灶(P1-3)者明显高于无肉眼可见腹膜转移灶(P0)者,浆膜受侵者明显高于浆膜未受侵者(P均〈0.05)。结论 两种方法均适用于胃癌腹腔脱落癌细胞的诊断或腹膜转移的预测,端粒酶活性检测微量癌细胞的灵敏度优于PLC法检测;胃癌端粒酶活性与恶性增殖活性密切相关;胃癌高增殖活性是浆膜受侵及腹膜转移的重要原因。  相似文献   
103.

Introduction

Mass casualty incidents involving victims with severe burns pose difficult and unique problems for both rescue teams and hospitals. This paper presents an analysis of the published reports with the aim of proposing a rational model for burn rescue and hospital referral for Switzerland.

Methods

Literature review including systematic searches of PubMed/Medline, reference textbooks and journals as well as landmark articles.

Results

Since hospitals have limited surge capacities in the event of burn disasters, a special approach to both prehospital and hospital management of these victims is required. Specialized rescue and care can be adequately met and at all levels of needs by deploying mobile burn teams to the scene. These burn teams can bring needed skills and enhance the efficiency of the classical disaster response teams. Burn teams assist with both primary and secondary triage, contribute to initial patient management and offer advice to non-specialized designated hospitals that provide acute care for burn patients with Total Burn Surface Area (TBSA) <20–30%. The main components required for successful deployments of mobile burn teams include socio-economic feasibility, streamlined logistical implementation as well as partnership coordination with other agencies including subsidiary military resources.

Conclusions

Disaster preparedness plans involving burn specialists dispatched from a referral burn center can upgrade and significantly improve prehospital rescue outcome, initial resuscitation care and help prevent an overload to hospital surge capacities in case of multiple burn victims. This is the rationale behind the ongoing development and implementation of the Swiss burn plan.  相似文献   
104.
目的 寻找与尿道下裂发病密切相关的基因,探讨尿道下裂形成机制.方法 ①实验组为12例尿道下裂患儿,年龄6~12个月,平均8个月.尿道下裂中度5例,重度7例.组织标本取自尿道成形手术时切取的尿道板组织.②对照组为6例年龄匹配的男性患儿,留取包皮环切时的正常表皮组织.用Tri-Reagent分别提取总RNA,与含22 000个人类基因的寡核苷酸基因芯片杂交、洗脱、染色、扫描,基因强度变化行方差分析(ANOVA,P<0.01)和Tukey分析,基因表达强度变化>2倍作为有意义的基因,比较尿道下裂和正常组织之间基因表达差异.从上调表达的基因中选择雌激素敏感基因行RT-PCR,标本除上述患儿RNA外,再增加年龄配对的3例中度、1例重度尿道下裂和2例年龄配对的RNA作为对照,即对照、中度和重度尿道下裂患者RNA标本各8例,验证芯片结果.结果 尿道下裂组织与正常组织之间存在明显的基因表达差异,共筛选出表达强度变化>2倍的基因94个,其中中度尿道下裂与正常比较,47个基因上调表达(P<0.01);重度尿道下裂与正常比较,68个基因上调表达(P<0.001);重度与中度比较,17个基因上调表达(P>0.05).上调表达的基因中发现了4个雌激素敏感基因CYR61、结缔组织生长因子、ATF3和GADD45β,基因芯片和RT-PCR均证实其在尿道下裂组织中的表达明显高于正常对照.结论 异常表达的基因与尿道下裂的发生有关,尿道下裂组织中雌激素敏感基因上调表达参与了尿道下裂的发病机制.  相似文献   
105.
106.
Recent experiments in cultured cyst epithelial cells from kidneys of patients with autosomal dominant polycystic kidney disease (ADPKD) have shown that the cystic fibrosis (CF) transmembrane conductance regulator (CFTR) is present in the apical surface of these cells and mediates chloride (Cl-) and fluid secretion in vitro. To determine whether the presence of CF with the expression of mutated CFTR proteins modifies cyst formation in ADPKD, we studied a large family with both inherited diseases. ADPKD in this family is linked to PKD1. The family is composed of 26 members; 11 members with ADPKD, 4 members with CF, and 2 members with both diseases. Renal volumes measured by computerized tomography (CT), calculated creatinine clearances, and other clinical parameters in the family members with ADPKD and CF were compared with those in the family members with ADPKD alone, as well as to a large population of patients with ADPKD. The patients with CF and ADPKD, but not the CF heterozygote carriers with ADPKD, had less severe polycystic kidney and liver disease, as indicated by normal renal function; smaller renal volume, even when corrected for height and body surface area; and the absence of hypertension and liver cysts. These observations suggest that the coexistence of CF may reduce the severity of ADPKD.  相似文献   
107.
目的检测Charcot-Marie-Tooth(CMT)病患者血清周围髓鞘蛋白22(PMP22)抗体、白细胞介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)水平,以探讨是否有免疫学机制参与CMT的病理生理过程。方法以人工合成PMP22胞外片段作为多肽抗原,用双抗体酶标法检测9名CMT1A患者和7名CMTX1患者血清PMP22抗体,同时检测IL-6和TNF-α水平;11名吉兰-巴雷综合征(GBS)患者和20名性别、年龄相匹配的正常人作对照。结果55.6%CMT1A患者和57.1%CMTX1患者PMP22抗体阳性,63.6%GBS患者和10%正常对照PMP22抗体阳性。正常对照组和CMT患者血清IL-6和TNF-α水平差异无统计学意义(P>0.05)。结论CMT1A患者PMP22抗体阳性与性别、年龄和病程均无关,但在CMTX1家系中,该抗体与性别相关(男性患者阳性),这可能是导致CMTX1家系中男性患者临床症状明显重于女性患者的原因之一。在CMT1A中,PMP22抗体的存在可能是对神经损伤的继发性反应而不是原发性病理过程,在CMTX1家系中存在继发性的免疫过程。此症可能不存在细胞因子介导的免疫损害。  相似文献   
108.
Survey of reproductive health among female MR workers   总被引:5,自引:1,他引:5  
  相似文献   
109.
The pattern of synaptic interactions between neurons of the nucleus tractus solitarius (NTS) has been analyzed using whole cell recording in rat brainstem slices. Following tractus solitarius (TS) stimulation 15/55 neurons presented a prolonged (up to 300 ms) increased excitability (PIE neurons) and 40/55 neurons presented a prolonged (up to 200 ms) reduced excitability (PRE neurons). In the absence of afferent sensory input all neurons showed spontaneous synaptic activity. Onggoing synaptic activity in PIE cells was glutamatergic and characterized by the absence of detectable inhibitory potentials while in PRE cells it was 90% GABAergic and 10% glutamatergic. Glutaminergic synaptic currents in PIE cells and GABAergic synaptic currents in PRE were studied using probability density and intensity functions. Distribution of time intervals between synaptic events indicated the latter were generated, in both PIE and PRE cells, by two simultaneous processes: (1) a close to Poisson process generating independent events; and (2) a subsidiary re-excitatory process generating synaptic events separated by intervals shorter than 20 ms. Blockade of glutamatergic transmission by 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX; 10 μM) or blockade of action potentials by tetrodotoxin (TTX; 1 μM) suppressed the subsidiary process. In conclusion, we propose that PIE cells (1) form a re-excitatory network contributing to generation of excitatory activity in the NTS and (2) are located presynaptically with respect to PRE cells.  相似文献   
110.
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