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11.
阿霉素磁性明胶微球的研究   总被引:2,自引:0,他引:2  
报告了阿霉素磁性明胶微球(Adr-MG-ms)的制备与性质,研究了超细氧化铁粒子的合成和磁性明胶微球(MG-ms)在狗体内的栓塞效果。阿霉素磁性明胶微球由2%阿霉素(Adr)、68%明胶和30%的磁铁粒子组成,微球的平均粒径为22μm。在体外实验中,药物释放速度证明微球有缓释的性质。磁铁粒子的平均粒径约为10nm,磁性明胶微球与 ̄(99m)Tc标记磁性明胶微球通过导管分别输入狗的肝动脉内进行栓塞,照相和血管造影显示在未加外磁场时磁性明胶微球在左右肝叶分布几乎相等,而在1200高斯的外磁场作用下,靶部位肝左叶的微球分布是肝右叶的2.25倍,而甲状腺、脑、心脏的微球很微量,结果表明磁性明胶微球在外磁场作用下是一个很好的治疗肝癌的栓塞剂。  相似文献   
12.
1. Endothelium-derived nitric oxide (NO) is a potent vasodilator. Because the body oxidizes it to nitrate ions, NO3-, measurement of the serum concentration and the urinary excretion of NO3- may be an index for endogenous NO. We investigated the role of NO on hyperdynamic circulation in cirrhotic and partial portal vein-ligated rats by measuring NO3. 2. Liver cirrhosis was induced by administration of thioacetamide. Systemic and splanchnic haemodynamics and splenic-systemic shunting were determined by tracer microspheres. The concentration of NO3- was measured by using high-performance liquid chromatography with an anion-column. 3. We found that systemic and splanchnic hyperdynamic circulation existed to almost the same extent in cirrhotic and in portal vein-ligated rats as compared to the controls and sham-operated rats, respectively. Splenic-systemic shunting was markedly greater in portal vein-ligated rats than in cirrhotic rats. 4. Serum NO3- levels and urinary excretion of NO3- in cirrhotic rats tended to increase as compared to the controls. On the other hand, the levels in portal vein-ligated rats were significantly increased as compared to those of the sham-operated rats, and were significantly and negatively correlated to the splanchnic arterial resistance and total vascular resistance. The amount of urinary excretion of NO3- significantly correlated to splenic-systemic shunting (r = 0.61, P<0.05) only in portal vein-ligated rats. 5. We suggest that these high levels of NO3- in portal vein-ligated rats relate to the extensive formation of porto-collateral vasculature or acute changes in systemic and splanchnic haemodynamics due to portal vein-ligation.  相似文献   
13.
隋继强  韩岩  吴红  郑岩  易成刚  郭树忠 《中国美容医学》2006,15(12):1342-1345,I0001
目的:制备碱性成纤维细胞生长因子(bFGF)、人表皮生长因子(EGF)可降解缓释微球,考察其生物活性的保存情况,以及它们对成纤维细胞的作用。方法:采用改良的乳化冷凝法交联制备复合bFGF、EGF的明胶缓释微球,将它们加入成纤维细胞的培养液中,用细胞计数法、四甲基偶氮唑盐微量反应比色法(MTT法)测定细胞增殖情况。结果:复合bFGF、EGF的缓释微球平均粒径(11.32±3.64)μm;培养1天后各组细胞计数、吸光度(A)值差异均无显著性;5天后,两种生长因子缓释微球组细胞计数、吸光度(A)值明显高于对照组;7天后,两种生长因子缓释微球组值仍高于其它组,但差异无显著性。结论:复合bFGF、EGF的缓释微球制备工艺简便,成球性好;能较长时间地持续释放活性bFGF、EGF,可促进成纤维细胞的增殖。  相似文献   
14.
Summary Experimental testicular torsion must be used for certain studies of clinical relevance, but most experimental models either do not provide hemodynamic alteration comparable to the clinical situation or cannot guarantee reproducibility. Using a rat model arterial perfusion and hemorrhagic infarction were correlated to the degree of both intra- and extravaginal testicular torsion. Arterial inflow was measured sequentially with radiolabelled microspheres, hemorrhagic infarction was judged by the increase of testicular weight. Maximal hemorrhagic infarction and reproducible values were found when the spermatic cord was twisted togehter with the tunica vaginalis for 360°–540°.  相似文献   
15.
The primary purpose of this study was to define regional blood flow in dogs with chronic tricuspid regurgitation (TR) in order to determine if the marked hypertrophy of the right atria resulted in compromised myocardial perfusion. Myocardial blood flow (ml/min/gm) was measured with radiolabeled microspheres in eight dogs with TR during rest, moderate exercise (5 dogs), and infusion of adenosine (1 mg/kg/min), an index of minimal vascular resistance. Similar measurements were obtained in eight normal dogs. In TR, the ratio of right atrium (RA) and right ventricle (RV) to body weight was greater than in normal dogs, 77 % and 30 %, respectively. During rest, flow in RA appendage was less than in nonappendage region in the normal dogs; no differences were noted in TR dogs, indicating an augmented hemodynamic role of the appendage in TR. Both RA and RV blood flow was greater in TR during rest but no other differences in flow were found between the two groups. Minimum vascular resistance in RV but not RA was slightly increased in TR versus normal. During marked myocyte hypertrophy, the vasculature of RA develops sufficiently to provide the same flow capacity as in the normal heart. Received: 11 June 1997, Returned for revision: 15 July 1997, Revision received: 11 August 1997, Accepted: 7 September 1997  相似文献   
16.
We studied the origin of transferrin receptor (CD71) positive cells in blood from seven women pregnant with a male fetus in order to explore if fetal cells could be detected among them. We used a technique that allows direct chromosomal analysis by in situ hybridization on immunologically and morphologically classified cells. Enrichment was performed by magnetic activated cell sorting (miniMACS)® using an anti-CD71 monoclonal antibody. The cells were immunophenotyped by alkaline phosphatase anti-alkaline phosphatase immunostaining with the same antibody. The origin of the immunophenotyped cells was studied by in situ hybridization using an X cosmid Y repeat chromosome specific probe cocktail. CD71 positive cells were found in six of the seven women at the range of 4 to 43 in respective samples. Over 90% of the CD71 positive cells were nucleated erythrocytes. None of the detected positive cells were shown to be fetal. Thus, the use of transferrin receptor antigen alone in combination with the miniMACS® may not be sufficient for enrichment of fetal cells.  相似文献   
17.
LINDBOM, L., TUMA, R. F. & ARFORS, K.-E.: Blood flow in the rabbit tenuissimus muscle: Influence of preparative procedures for intravital microscopic observation. Acta Physiol Scand 1982, 114 :121–127. Received 21 April 1981. ISSN 0001–6772. Department of Experimental Medicine, Pharmacia AB, Uppsala, Sweden. The tenuissimus muscle in the rabbit and the cat is a suitable tissue for intravital microscopic investigation of skeletal muscle blood flow. In this study the influence of surgical procedures necessary for direct microscopic observation on the physiological state of the rabbit tenuissimus muscle was assessed by means of blood flow measurements. Mean resting blood flow was 2.8±0.8 (mean ± S.D.) ml. min-1. 100 g-1 in the left tenuissimus muscle when prepared for microscopic observation as determined by the radioactive microsphere method. This value was not significantly different from that in the intact unexposed muscle in the contralateral leg, 3.3 ±1.1 ml. min-1. 100 g-1. Exposure of the muscle to atmospheric oxygen tension resulted in a reduction of blood flow to 0.7±0.4 ml. min-l. 100g-l, suggesting that local metabolic control mechanisms were active. The normal range of vascular control seemed to be maintained, as demonstrated by an increase in blood flow to 64.2± 18.8 ml. min-1. 100 g-l during “maximal” vasodilation induced by topical application of PGE1. The tenuissimus muscle showed a marked sensitivity to mechanical stimulation. Slight stretching of the muscle, similar to what may occur during surgical preparation, resulted in an increase in blood flow to 17.5±5.7 ml. min-1. 100 g-1. Flow values calculated from data obtained by direct microscopic measurements in the tenuissimus muscle agreed well with those obtained by the microsphere method.  相似文献   
18.
The detection of isolated tumor cells (ITC) in the bone marrow of patients with epithelial malignancies is an independant prognostic factor for several entities as breast cancer, colorectal cancer or non-small lung cancer. However, with conventional immunocytology using Ficoll density gradient and APAAP staining, only a small proportion of the bone marrow samples can be scanned for cytokeratin-positive (CK+) cells. To improve detection rates, we evaluated the enrichment of ITC by magnetic activated cell sorting (MACS) compared to regularly stained cytospins. Recovery experiments with a CK+ breast cancer cell line (SKBR3) were performed to calculate the MACS enrichment rate. Bone marrow was obtained by aspiration from 20 patients with carcinomas of epithelial origin and from 17 controls. ITC were enriched and stained with magnetically labeled CAM 5.2 antibodies directed to cytokeratin 7 and 8. MACS of SKBR3 seeded in peripheral blood revealed average recovery rates of 62% and 48% and average enrichment factors of 104-fold and 8139-fold of the CK+ cells after one and after two separations, respectively. After immunomagnetic enrichment, CK+ cells were detected in 16 of 20 (80%) cancer patients, whereas only 7 (35%) patients showed CK+ cells without magnetic enrichment (P=0.002). Ten of twelve (83%) patients with metastatic disease (stage M1) and six of eight (75%) patients without any overt metastases (M0) had CK+ cells in their bone marrow. None of the negative controls showed any CK+ cells. Enrichment with magnetically labeled anti cytokeratin antibodies increases the detection rate of epithelial cells in bone marrow of cancer patients compared to immunocytology. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
19.
Summary After injections in the cat of Rhodamine labelled latex microspheres in the amygdala and of Fast Blue in the cerebellum neurons labelled with one of these tracers as well as some double labelled neurons were found in the parabrachial nucleus, the nucleus locus coeruleus and some adjacent nuclei (the nucleus subcoeruleus and the pontine tegmental reticular formation). All double labelled cells were located on the ipsilateral side. A few double labelled neurons were also found bilaterally in the dorsal raphe nucleus. It therefore appears that a certain number of cerebellar projecting neurons in these brain stem nuclei by means of divergent axon collaterals also project to the amygdala. The location of the double labelled cells found in this study suggests that at least some of the neurons are catecholaminergic. The findings are related to previous reports on the distribution of catecholaminergic neurons and on the amygdaloid and cerebellar projections from this part of the brain stem, and the possible involvement of these connections in cerebellar non-somatic responses are discussed. Some comments are made concerning the use of fluorescent latex microspheres for double labelling studies in combination with another fluorescent tracer.  相似文献   
20.
目的 :研究小鼠博来霉素在肺纤维化模型中肺泡巨噬细胞(AM)分泌的基质金属蛋白酶 9(MMP 9)和基质金属蛋白酶抑制剂 1(TIMP 1)的表达随着时间的变化 ,观察肺纤维化中MMP 9和TIMP 1的表达是否存在失衡。方法 :以博来霉素诱导建立小鼠肺纤维化模型 ,采用HE染色观察肺部胶原沉积状况。选用抗CD6 8mAb ,采用微小免疫磁珠法分离纯化肺泡灌洗液中的AM ,用Hoechst 332 5 8染色AM ,在下光镜高倍视野计数法评估AM的纯度和活性 ,用EIA法检测AM上清液中MMP 9和TIMP 1的表达。结果 :肺组织切片HE染色显示小鼠肺部胶原沉积在 1、3、7、14、2 8d呈逐渐加重趋势。粗分离的AM纯度为 (82 .5± 2 .5 ) %。采用微小免疫磁珠法分离肺泡灌洗液中的AM纯度可达到 (99.3± 0 .7) % (P <0 .0 5 )。纯化后的细胞存活率为 (92 .5± 1.8) % ,与纯化前的 (92 .7± 2 .0 ) % ,相差不大 (P >0 .0 5 )。随着小鼠肺间质纤维化的进展 ,MMP 9的分泌量逐渐减少 ,而TIMP 1的表达量逐渐增加。结论 :在小鼠肺纤维化中AM分泌的MMP 9和TIMP 1之间存在失衡 ,表明基质降解系统受到抑制  相似文献   
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