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101.
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
102.
T J Wieman T S Mang V H Fingar T G Hill M W Reed T S Corey V Q Nguyen E R Render 《Surgery》1988,104(3):512-517
The aim of this series of experiments was to determine the dynamic blood flow changes that occur in normal and neoplastic tissues during photodynamic therapy. Mice bearing SMT-F tumors and rats with transplanted chondrosarcomas were injected with graded doses of dihematoporphyrin ether. Studies of changes in single-vessel and whole-tumor blood flow were carried out with 630 nm light activation. A helium neon laser Doppler velocimeter was used to stimulate dihematoporphyrin ether, as well as to measure changes in flow velocity in both single-vessel and whole-tumor models. There was a reduction of flow velocity in all vessels and tumors in animals injected with 1 to 40 mg/kg dihematoporphyrin ether intraperitoneally. The extent of flow reduction was related to drug dose administered. Decreases in blood flow began within 10 seconds of light stimulation and were maximal within 5 minutes. Both normal and tumor vessels responded similarly. We conclude that photodynamic therapy leads to significant microcirculatory changes that may be pertinent to the mechanism of tumor necrosis. 相似文献
103.
William F Astle Vivian E Hill Anna L Ells Nguyen Thi Thanh Chi Elaine Martinovic 《Journal of AAPOS》2003,7(5):339-344
BACKGROUND: Congenital absence of the inferior rectus muscle is a rare cause of apparent inferior rectus palsy especially in the absence of associated cranial facial anomalies. METHODS: We report three cases of isolated congenital absence of the inferior rectus muscle and its successful surgical management. RESULTS: Failure of the normal embryologic development of the mesodermal complex around the eye can lead to agenesis of the extraocular muscles. In apparent palsies of the inferior rectus muscle and no definite cause, a high index of suspicion and orbital imaging can confirm the diagnosis of congenitally absent inferior rectus preoperatively. Surgical correction may involve inferior transposition of the horizontal rectus muscles. CONCLUSIONS: Although rare, congenital absence of the inferior rectus muscle is a possible cause of apparent inferior rectus muscle palsy particularly in the absence of another identifiable cause. Strabismus surgery in conjunction with intramuscular botulinum toxin injection can offer significant improvement in function and cosmesis of these patients. 相似文献
104.
目的 了解广州港中小学生的营养状况。方法 收集1997-2002年广州港4所中小学生的体检资料。结果 广州港4所中小学生平均营养不良发病率为23.39%,肥胖发病率为6.34%。营养不良发病率有逐年下降的趋势,而肥胖发病率则有逐年上升的趋势。男女性别间差异有显性意义(P<0.01)。结论 中小学生营养不良与肥胖同时存在。今后的学生营养工作应防治中小学生营养不良与肥胖并举,全面推行以学校为中心的全民营养教育。 相似文献
105.
目的探讨ras基因在人乳腺癌及良性疾患组织中的表达情况及其与淋巴结转移等预后因素之间的关系。方法乳腺组织标本共万例,以昆抗人之panras单抗IgG2b及免疫组化方法检测ras基因在乳腺组织中的表达产物。结果rasP21位于胞浆;rasP21在乳腺癌中表达率为63.6%,而在所有良性乳腺疾患中仅1例阳性;rasP21表达与乳腺癌淋巴结转移正相关,且同一病人13对原发灶及淋巴结转移灶配对标本中有9对表达一致。结论rasP21的检测在评估乳腺癌淋巴转移及良恶性病变上有肯定意义,P21是评估乳腺癌患者预后有价值的生物学指标。 相似文献
106.
107.
Not many data exist to guide us in the management of patients with chronic hepatitis B virus infection and “normal” alanine
aminotransferase levels. Many of these patients may not have normal levels on long-term follow-up or when the upper limit
of normal is determined from a truly healthy reference population. These patients may have significant histologic disease
and benefit from further investigation or treatment. This article focuses on the disease course of such patients. 相似文献
108.
A turkey red blood cell haemagglutination assay (TRBC HA) allowing rapid measurement of the antibodies against tetanus has been set recently. Its feasibility was evaluated in injured patients admitted into an emergency unit during summer 1987. TRBC HA was performed by the same physician who questioned the patient on his/her previous vaccinations and evaluated his/her immunization status. The rapid HA test practiced in emergency was controlled by TRBC HA and ELISA measurement of antibodies carried out in the laboratory. Each method was compared to the others: the results were fitted and no significant difference was found. The preventive procedures which would have followed the antibody measurement by immediate TRBC HA were compared to the decision resulting from clinical evaluation. The immunoprophylactic attitude would have been the same in 82% of cases. TRBC HA is a reliable test, and feasible in an emergency: it could help in making the appropriate decision for immunoprophylaxis to be applied to the injured and other patients at risk of tetanus. 相似文献
109.
Prevalent vertebral deformities: Relationship to bone mineral density and spinal osteophytosis in elderly men and women 总被引:4,自引:0,他引:4
G. Jones C. White T. Nguyen Prof. P. N. Sambrook P. J. Kelly J. A. Eisman 《Osteoporosis international》1996,6(3):233-239
The aims of this study were to ascertain vertebral deformity prevalence in elderly men and women and to describe the association between bone mineral density (BMD) at the lumbar spine and femoral neck, severity of spinal degenerative disease and vertebral deformity prevalence. We performed standardized spinal radiographs in a random sample of 300 elderly men and women participating in the Dubbo Osteoporosis Epidemiology Study, a population-based study of fracture risk factors. Radiographs were read independently by masked observers for the prevalence of vertebral deformity and severity of osteophytosis. BMD was measured by dual-energy X-ray absorptiometry. The prevalence of vertebral deformities was critically dependent on the criterion used. The less strict criteria seemed to overestimate deformities at either end of the spine region analysed. However, irrespective of the criterion used, prevalence of deformity was higher in men than in women (25% vs 20% for the 3 SD criterion, 17% vs 12% for the 4 SD criterion and 27% vs 25% for the 25% criterion). Femoral neck BMD was more strongly associated with vertebral deformities than spinal BMD for the 25% criterion (OR/SD change in BMD 1.39 (p=0.02) vs 1.20 (p=0.19)), 3 SD criterion (OR/SD change in BMD 1.45 (p=0.01) vs 1.10 (p=0.34)) and 4 SD criterion (OR/SD change in BMD 1.98 (p=0.0002) vs 1.68 (p=0.008)). BMD was also more strongly associated with biconcave deformities than either wedge or crush deformities and more so in men than in women. Severity of spinal osteophytosis was not associated with vertebral deformity. In conclusion, femoral neck BMD is at least equivalent to the lumbar spine BMD in strength of association with prevalent vertebral fractures. Spinal osteophytosis falsely elevates BMD without a concomitant decrease in fracture risk, indicating that any interpretation of spinal BMD needs to be adjusted for osteophytosis. These findings support the use of femoral neck bone densitometry in older men and women. Moreover, these data indicate that current criteria for radiological assessment of vertebral deformity are sufficiently loose to include a substantial proportion of non-fractures in the elderly, with important implications for the design of clinical trials. However, irrespective of the criterion used, vertebral deformities in men are at least as common, if not more so, than in women, suggesting that vertebral osteoporotic fractures are overlooked in men. 相似文献
110.