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31.
OBJECTIVE: To observe the morphological changes of Balb/C mouse embryonic stem cells following directed differentiation into pancreatic islet-like cell clusters (PICC) in vitro using atomic force microscope (AFM). METHODS: Balb/C mouse embryonic stem cells were first cultured into embryonic bodies (EBs) and allowed to differentiate spontaneously for 4 days. The cells were then transferred to gelatin-coated dishes for the EBs to attach and spread on the tissue culture plates, in the course of which a series of cell growth factors such as basic fibroblast growth factor (bFGF), insulin-like growth factor 1 (IGF-1) and nicotinamide were added into the culture medium at specific time points to induce directed differentiation of the stem cells into PICC. Immunocytochemistry was employed to detect the cells positive for insulin and glucagon, which were observed with AFM. RESULTS: The embryonic stem cells developed into cell clusters of different sizes, in which the cells were tightly arranged. Islet B cells were numerous in the center of clusters and darkly stained, but fewer in the peripherals with lighter stains. Islet A cells expressing glucagon were relatively fewer in the cell clusters, found mainly in the peripherals. Scanning of the insulin-positive clusters by AFM revealed large quantity of tissue fibers resembling nerve fibers that formed a reticular structure in disorderly arrangement. Numerous round granules were observed in the cytoplasm of almost identical sizes ranging from 0.5 to 1.0 mum in diameter. CONCLUSION: The cell clusters obtained by directed differentiation are mature in both morphology and function with also well organized structures. 相似文献
32.
目的探讨膀胱出口梗阻(BOO)后逼尿肌收缩蛋白表达和膀胱重量的改变及意义。方法BOO组病人16例,筛选条件为入院诊断良性前列腺增生症(BPH)并经尿动力学压力-流率检查证实为高压低流型;对照组5例,为外伤等情况入院并排除有下尿路梗阻病史者。BOO组所有病例均行耻骨上经膀胱前列腺摘除术,术前B超检查测定膀胱重量和前列腺内外径比值,术中切取膀胱上壁组织2cm×1cm×1cm大小,标本行RT-PCR反应,检测膀胱逼尿肌中肌动蛋白和肌球蛋白mRNA的表达,并比较其与膀胱重量间的线性相关性。结果BOO组与对照组膀胱重量分别为(92.15±34.89)g和(56.08±20.35)g,(P<0.05);前列腺内外径比值分别为(0.57±0.16)和(0.18±0.06),(P<0.01);与对照组相比,BOO组肌动蛋白和肌球蛋白mRNA的表达量均有显著增加,分别为(40.32±59.67)×106和(6.59±5.62)×106,(P值均<0.01);且两者表达量与膀胱重量之间均有明显线性正相关性(P<0.05)。结论逼尿肌中肌动蛋白和肌球蛋白的表达与膀胱逼尿肌的功能状态密切相关。 相似文献
33.
肝尾状叶由于解剖位置特殊,位置深,难以显露,手术难度大,是肝脏外科领域手术操作的难点与研究热点.随着肝血流控制技术的发展、肝实质离断技术的提高,肝尾状叶肿瘤切除率明显提高[1].2006年4月至2008年10月,我科完成单独肝尾状叶血管瘤切除术9例,现将手术技巧与疗效报道如下. 相似文献
34.
This review summarized some articles on the effect of the septal area in acupuncture analgesia. The data showed that the pain threshold of animal was increased when septal area was stimulated by electro-acupuncture, and that electrical stimulation of septal area had a marked inhibitory effect on the pain discharges of cells in parafascicular nucleus of thalamus, lateral habenular nucleus, periaqueductal gray and dorsal raphe nucleus. The septal area play an important role in acupuncture analgesia. The majority of the cholinergic neurons in septal area are located in nucleus of the vertical limb of the diagonal band (VDB); gamma-aminobutyric acid of septal area is mainly found in the diagonal band nucleus(td); Dopamine is present in high levels in td and lateral septal nucleus(S1) of septal area; The S1 contain high densities enkephalin-containing neuronal cell bodies and terminals; In addition, substance P and norepinephrine are also high levels in the septal area. These substance above-mentioned have a relations with acupuncture analgesia of septal area. A large number of serotonin-containing neurons are found in the raphe nuclei. The serotonin play an important role in acupuncture analgesia. The serotonin-containing neurons in dorsal raphe nucleus project to S1. The fiber connections of the raphe nuclei with the td are reciprocation. The periaqueductal gray is a important structure on pain modulation. It projects to septal area and receives the fibers from S1. A number of adrenergic neurons are located within the locus coeruleus. The locus coeruleus participate pain modulation and acupuncture analgesia. The neuro-anatomy study demonstrated that locus coeruleus projects to septal area.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
35.
观察加用青霉烷砜后氨苄青霉素对痢疾杆菌的体外杀菌效果。结果表明,加用青霉烷砜后对69株痢疾杆菌的杀菌效果,从单纯氨苄青霉素的杀菌率59.4%(41/69)提高到98.6%(68/69),有显著增效作用(P<0.005)。各株痢疾杆菌对国产和墨西哥产氨苄青霉素的敏感性无差异。证明青霉烷砜对氨苄青霉素有增效作用,对原耐氨苄青霉素痢疾杆菌的杀菌率达96.4%(27/28)。对耐药痢疾杆菌治疗药物的选择提供了有益的参考。 相似文献
36.
以健康Wistar大白鼠为材料,对微波快速内源性过氧化物酶染色与灌注法显示微血管的方法进行了对比研究。结果,过氧化物酶组织化学法具有不用灌注,操作简单,所用时间短,对血管无扩张、破裂等人为改变的特点,保持了微血管真实的自然形态和管径大小,可以定量或半定量地判定组织器官活体时的血液循环状况。可以用于人及动物的大脑、脊髓、皮肤、耳及食管等组织内微血管形态学研究和定量分析。并对过氧化物酶显示微血管的原理和微波辐射促进染色的原理及特点进行了分析、讨论。 相似文献
37.
本文报道五例肿瘤患者在用抗癌药的治疗过程中,出现对心脏不同程度的毒性反应,并就有关几种抗癌药物的毒性作用机理及防治进行了讨论。 相似文献
38.
某化工厂1987~2000年164例工伤事故调查分析 总被引:2,自引:0,他引:2
目的调查分析某化工厂工伤事故的分布规律及其危险因素,以便采取相应的预防干预措施。方法对1987~2000年该化工厂发生的工伤事故进行回顾性调查分析,建立数据库,并统计分析。结果 ①事故以轻伤为主,约占80.0%。②事故类别主要是灼烫烧伤和机械伤害,分别为工伤事故总数的35.8%、28.5%。③工伤伤害性质以骨折多见,约为总数的56.1%。④受伤工人的年龄分布以30~40岁段为主,约为总数的31.1%。⑤工伤事故原因中注意力不集中和违反操作规程分别为总数的43.0%,38.3%。结论12根据上述流行病学特点,采取相应的措施来减少工伤事故的发生。 相似文献
39.
The effects of radiofrequency catheter ablation on the metabolic enzymes and Ca++-ATPase of myocytes
Summary Using histochemical technique, the effects of radiofrequency catheter ablation (RFCA) on the activities of LDH, SDH, CCO,
and Ca++-ATPase of guinea-pig ventricular myocytes were examined. The histological changes were observed for comparison. Radiofrequency
energy (500 kHz) delivered was 20 WX 10 s. The results were as follows: RFCA resulted in significant impairments in all the
four kinds of enzymes but without statistical differences in the areas involved in this energy level. No statistically significant
difference was found between the ranges of enzymatic damages and areas of pathological lesions. These findings showed a consistency
in areas of the histological and histochemical lesions resulted from RFCA. 相似文献
40.
通过对医疗纠纷产生的原因进行分类,提出一套有针对性的处理医疗纠纷的方法,依照客观公正的原则及时处理,并建议医院成立一支处理医疗纠纷的的专门队伍和机构。 相似文献