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101.
目的:用药物预适应方法进行干细胞诱导已有报道,本实验观察中药参三七皂苷Rg1对5-氮胞苷诱导大鼠骨髓间充质干细胞向心肌细胞转化中的作用。方法:实验于2003-01/05在南京医科大学药理教研室完成。①实验材料:清洁级SD大鼠8只。参三七皂苷Rg18mg,批号20021017,由云南省长春花生物制剂公司提供,加入不含胎牛血清的IMDM培养液10mL,调配成10-4mol/L溶液,4℃保存。5-氮胞苷(Sigma公司,批号021209)。②实验方法:贴壁法体外培养大鼠骨髓间充质干细胞。设立4组:空白对照组常规培养后进行无血清处理,每3d换液1次;5-氮胞苷单用组单纯以10μmol/L的5-氮胞苷进行处理,其终浓度为1×10-8moL/L,连续诱导15d;5-氮胞苷 参三七皂苷Rg1预适应组分别加入0.1,1μmol/L参三七皂苷Rg1培养液处理24h,再各以10μmol/L的5-氮胞苷进行诱导,其终浓度为1×10-8moL/L,连续诱导15d。③实验评估:取第2代骨髓间充质干细胞,绘制生长曲线并计算群体倍增时间。观察诱导后骨髓间充质干细胞的生长形态学特征和细胞超微结构变化。激光共聚焦显微镜测定细胞表面积变化和细胞内钙离子浓度。结果:①5-氮胞苷诱导后骨髓间充质干细胞的生长形态学特征和细胞超微结构变化:骨髓间质干细胞胞体逐渐增大并伸出细长突起,在突起末端出现分支,部分相邻细胞的突起连接成网,形态学上表现出向心肌细胞方向转化的特征。其超微结构呈梭形,有明显的肌丝,细胞核呈单椭圆形,位于细胞中央,间质干细胞形似心肌细胞。②参三七皂苷Rg1预适应对5-氮胞苷诱导的骨髓间充质干细胞增殖特性的影响:与5-氮胞苷单用组比较,5-氮胞苷 参三七皂苷Rg1预适应组从第3天开始细胞数明显增加,细胞生长曲线均无明显的生长平台期,达到高峰后细胞数开始减少。③参三七皂苷Rg1预适应对5-氮胞苷诱导的骨髓间充质干细胞表面积的影响:与空白对照组骨髓间充质干细胞表面积比较,5-氮胞苷单用组明显降低,0.1,1μmol/L参三七皂苷Rg1预适应则能显著升高5-氮胞苷诱导的骨髓间充质干细胞表面积(P<0.01)。④参三七皂苷Rg1对5-氮胞苷诱导的骨髓间充质干细胞内游离钙水平的影响:与空白对照组比较,5-氮胞苷诱导4周后骨髓间充质干细胞内游离Ca2 相对荧光强度均明显升高(t=6.72,P<0.01),且5-氮胞苷 1μmol/L参三七皂苷Rg1预适应组升高幅度大于5-氮胞苷单用组(t=3.13,P<0.05)。结论:①参三七皂苷Rg1预适应在体外可显著刺激5-氮胞苷诱导的鼠骨髓间充质干细胞向心肌细胞转化和增殖,改善细胞形态,刺激细胞内钙离子增加。②参三七皂苷Rg1与5-氮胞苷对骨髓间充质干细胞向心肌细胞定向分化产生协同效应。  相似文献   
102.
BACKGROUND: Expensive devices have been developed for the collection and transfusion of blood salvaged after hip or knee arthroplasty. STUDY DESIGN AND METHODS: The volume of salvaged red cells was measured for the first 6 hours after operation. This volume was compared to total red cell loss during hospitalization and to the volume of allogeneic red cells transfused. RESULTS: Mean postoperative red cell loss in 31 patients following hip replacement was 55 +/− 29 mL and that in 20 patients following knee replacement was 121 +/− 50 mL. The 6-hour wound drainage represented 8.7 and 16.8 percent of overall red cell loss during hospitalization for hip and knee replacement, respectively. The transfusion of postoperatively salvaged red cells would have supplanted transfusion of less than one-third of a unit of allogenic blood after hip replacement and two-thirds of a unit after knee replacement. Only three patients (5.9%) lost red cell volume in the drainage equivalent to or in excess of 1 unit of red cells (180 mL). The volume of red cells salvaged postoperatively bore no relationship to perioperative red cell losses as a whole. CONCLUSION: The relatively small red cell loss in the postoperative period in most arthroplasty patients does not appear to justify the routine use of this technique for the recovery of autologous blood.  相似文献   
103.
Epidemiological analyses of injury patterns and mechanisms help to identify the expertise military surgeons need in a combat setting and accordingly help to adjust infrastructure and training requirements. Therefore, a MEDLINE search (1949–2009), World Wide Web search (keywords “combat, casualties, war, military, wounded and neurosurgery”) and an analysis of deaths among allied war casualties in Afghanistan and Iraq were performed. Up to 10th December 2009 there had been 4,688 allied military deaths in Iraq and 1,538 in Afghanistan. Of these 22% died in non-hostile action, 33% in direct combat situations and the majority of 45% in indirect combat actions. The leading causes of injury were explosive devices (70%) and gunshot wounds. Chest or abdominal injuries (40%) and traumatic brain injuries (35%) were the main causes of death for soldiers killed in action. The case fatality rate in Iraq is approximately half that of the Vietnam War, whereas the killed-in-action rate in Afghanistan (18.7%) is similar to the Vietnam War (20%); however, the amputation rate is twice as high in modern conflicts. Approximately 8–15% of the fatal injuries seem to be potentially survivable. Military surgeons must have an excellent expertise in a wide variety of surgical specialties. Life saving emergency care, especially in the fields of thoracic, visceral and vascular surgery as well as practical skills in the fields of neurosurgery and oral and maxillofacial surgery are required. Additionally, it is of vital importance to ensure the availability of sufficient tactical and strategic medical evacuation capabilities for the wounded.  相似文献   
104.

Objective

To investigate the impact of intermittent interleukin‐2 (IL‐2) plus combination antiretroviral therapy (cART) on HIV‐1 entry co‐receptor use.

Methods

Primary HIV‐1 isolates were obtained from 54 HIV‐1‐positive individuals at baseline and after 12 months using co‐cultivation of peripheral blood mononuclear cells (PBMC) with activated PBMC of HIV‐negative healthy donors. HIV‐1 co‐receptor use was determined on U87‐CD4 cells.

Results

Fourteen out of the 21 (67%) IL‐2‐treated individuals harbouring a primary CCR5‐dependent (R5) HIV‐1 isolate at baseline confirmed an R5 virus isolation after 12 months in contrast to 3 out of 7 (43%) of those receiving cART only. After 12 months, only 1 R5X4 HIV‐1 isolate was obtained from 21 cART+IL‐2‐treated individuals infected with an R5 virus at entry (5%) vs. 2/7 (29%) patients receiving cART alone, as confirmed by a 5‐year follow‐up on some individuals.

Conclusions

Intermittent IL‐2 administration plus cART may prevent evolution towards CXCR4 usage in individuals infected with R5 HIV‐1.
  相似文献   
105.
目的对实验动物皮肤病原真菌2种培养方法进行了比较。方法将采集到的3只皮肤真菌感染病兔样品经由沙氏平皿法和沙氏试管斜面培养法分别进行培养。结果在3只真菌感染病兔中应用试管斜面法我们只检测到1例皮肤病原真菌阳性,而采用沙氏平皿法3例阳性全部检出。结论结合临床检测经验,我们认为本研究的沙氏平皿法优于沙氏试管斜面法,在实验动物皮肤病原真菌常规检测中具有推广应用价值。  相似文献   
106.
目的 建立大鼠血浆中栀蒡热毒平方有效组分中栀子苷、牛蒡子苷和黄芩苷的HPLC血药浓度测定方法.方法 血浆样品采用甲醇-乙腈(1∶ 1)沉淀蛋白,HPLC测定血药浓度.色谱柱为Diamonsil C18柱(4.6 mm×150 mm, 5 μm),流动相乙腈-0.2%磷酸水梯度洗脱,流速1.0 mL/min,检测波长238 nm和278 nm.结果 各成分的最低检测浓度(S/N>3)在0.23~0.32 mg/L,平均回收率均在85%以上,日内、日间精密度及稳定性的RSD均小于10%.结论 该方法简便、准确,可作为栀蒡热毒平方血药浓度定量分析方法.  相似文献   
107.

INTRODUCTION

Published colorectal cancer surgery data suggest no role for the analysis of the anastomotic doughnuts following anterior resection. The usefulness of routine histological analysis of the upper gastrointestinal doughnut is not clear. Our study assessed the impact of cancer involvement of the doughnut on clinical practice. Factors associated with doughnut involvement and the effect on patients'' survival were also analysed.

PATIENTS AND METHODS

The clinicopathological details of 462 patients who underwent potentially curative oesophagogastrectomy for cancer with a stapled anastomosis between 1994 and 2006 in two specialist centres were retrospectively analysed. Univariate, multivariate and survival analyses were carried out.

RESULTS

Approximately 5% of doughnuts (22 of 462) were histologically involved with cancer. Microscopic involvement of the proximal resection margin, local lymph node metastasis and lymphatic invasion within the main resected specimen were independently associated with doughnut involvement (all P < 0.05). However, these three factors taken together failed to predict doughnut involvement. Doughnut involvement was an independent adverse prognostic factor for overall survival (P = 0.0013).

CONCLUSIONS

In contrast to findings in colorectal surgery, doughnut involvement with cancer appears to have useful prognostic information following oesophagogastrectomy. Routine histological analysis of upper gastrointestinal doughnuts is justified. Doughnut involvement could potentially strengthen the indications for adjuvant therapy in the future.  相似文献   
108.

Introduction

Breast gangrene has been reported as a complication following puerperal sepsis, breast surgery, nipple piercings, warfarin toxicity, etc. We report a case of primary breast gangrene in an HIV-positive individual which, to the best of our knowledge, is the first of its kind.

Case report

A 40-year-old previously healthy woman presented with fulminating left breast gangrene. She was detected to be HIV positive. Mastectomy was performed. The detailed management of the condition is discussed.

Conclusion

Severe necrotising infections may be initial manifestations of HIV infection and patients with such infections should be screened for HIV.  相似文献   
109.
子宫结合带(JZ)是MRI上显示的子宫壁正常结构,JZ在MRI上呈低信号。妊娠期以外的子宫结合带是依赖雌激素的周期性调控来控制子宫的收缩运动的,除此之外,许多生物因子都参与了JZ的调节,如CX43、干扰素因子IFNγ、细胞活素和生长因子等。JZ与子宫肌瘤、子宫内膜异位症、子宫腺肌症、妊娠期并发症、不孕、胚胎植入等的发生均有关,其相关研究现在主要聚集在MRI方面的研究,本文综述了子宫结合带的调节因素及相关疾病。  相似文献   
110.
Certain neurobehavioral deficiencies associated with Turner Syndrome have been attributed to brain volumetric abnormalities, particularly of the amygdala. Haplo-insufficiency of a non-dosage compensated gene or genes on the X chromosome has been hypothesized to be the cause of the neuroanatomical defect. We examined gene expression levels of 6,628 genes in developing amygdalae of late-stage embryos of a mouse model for Turner Syndrome. In total, 161 genes show significant differences in expression level between TS and normal female amygdala. In silico pathway analysis of both X-linked and autosomal mis-regulated genes suggests that modulation of Wnt signaling is a critical factor in the normal growth and development of the amygdala. Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.  相似文献   
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