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901.
Using two different immunocytochemical approaches at the electron microscopic level, it was shown that substances related to enkephalin and somatostatin coexist in the same granules in the median eminence of the guinea-pig. This finding means that the two neuropeptides are simultaneously released. The possible inhibiting action of enkephalins on somatostatin release is discussed related to other data. 相似文献
902.
Abstract – Radioactive chromium, cobalt, gold and mercury, all of which may occur as corrosion products from dental restorations, were injected in single doses via the tail vein of mice and an in vivo analysis of their distribution was performed using whole-body autoradiography. Gold seemed to be inert and went mainly to the liver and bones. The other elements studied were distributed widely in the body and remained for a long period of time in specific target organs and tissues. 相似文献
903.
本文介绍在福尔马林固定的石蜡切片上用间接免疫组化技术显示抗原的一种新方法——免疫金-银法。免疫金与抗原结合后用银复染,可大大提高灵敏度。在肝、胃组织用免疫金-银法确定HBsAg及5-HT抗原取得满意结果。 相似文献
904.
Yutaka Takasaki Seikichi Sekine Yoshimasa Matsuzawa Seinosuke Iwata Makoto Sasaoka 《Toxicology letters》1979,4(5):327-343
The effects of parenterally and orally administered monosodium l-glutamate (MSG) on somatic growth were studied in rats. Neonatal rats receiving 10 s.c. injections of 4 g/kg body wt. showed hyperphagia only in the postweaning stage: at maturity they were obese, hyperlipidaemic and stunted, with reduced nasoanal and tail length, reduced endocrine and other organ weights and almost complete absence of neurons of the arcuate nucleus (AN). Low blood pressure and high heart rate were recorded in males. Infant rats receiving 10 injections of 4 g/kg of MSG showed milder disturbances. Neonatal or infant rats given repetitive doses of 0.2 or 0.5 g/kg showed parallel weight gains to those of controls. Weanling rats fed a diet containing 5% MSG for 10 days, following earlier intubation, consumed 7 g/kg body wt. per day of MSG without effect, their AN remaining normal. These data indicate that an adverse effect from MSG on somatic growth is not induced in so far as the AN neurons are not injured following any route of administration. 相似文献
905.
贴壁培养细胞胶体金免疫电镜标本制备技术的改进 总被引:1,自引:1,他引:0
介绍一种贴壁培养细胞胶体金免疫电镜标本制备方法,本法适用于观察各种因素对细胞表面抗原性质影响的免疫电镜研究。 相似文献
906.
Using anti-VEGF McAb and magnetic nanoparticles as double-targeting vector for the radioimmunotherapy of liver cancer 总被引:7,自引:0,他引:7
To study the biodistribution of a new radioimmunoconjugate-131I-anti-VEGF monoclonal antibody (Sc-7269)-Dextran Magnetic Nanoparticles (DMN) in nude mice bearing human liver cancer where an external magnetic field was focused on, and to evaluate its therapeutic effects and safety. Tumor Growth Delay (TGD) and tumor inhibition rate were observed as antitumor effect. Peripheral white blood cells counts and the loss of body weight were tested as an indicator of systemic toxicity. The results suggests that the radioimmunotherapy of intratumoral injection of 131I-Sc-7269-DMN may be safe and efficient for the treatment of liver cancer. Furthermore, the radioimmunotherapy using DMN as a 'carrier system' may be a highly potential approach in the treatment of other kind of tumors. 相似文献
907.
磁性聚乳酸羟基乙酸氧化酚砷纳米微粒对人肝癌细胞生长的抑制作用 总被引:1,自引:1,他引:0
目的〖HT5”SS〗:研究磁性聚乳酸羟基乙酸氧化酚砷纳米微粒对人肝癌细胞生长的抑制作用。〖HT5W〗方法〖HT5"SS〗: 运用超声乳化溶剂挥发法制备磁性聚乳酸羟基乙酸氧化酚砷纳米微粒;透射电镜观察纳米微球形态; MTT法检测纳米微粒对肝癌细胞SMMC7721生长的抑制作用;流式细胞术检测细胞凋亡。〖HT5W〗结果〖HT5”SS〗: 磁性聚乳酸氧化酚砷纳米微粒外观呈规则球型,其粒径尺寸平均为290 nm。磁性纳米微粒抑制人肝癌细胞增殖,且具有一定的时间和浓度依赖性。1.0 μmol/L纳米微粒组作用24 h肝癌细胞生长的抑制率为(4.6±0.9)%,作用48 h抑制率为(11.4±1.2)%。流式细胞术检测可见肝癌细胞凋亡峰出现,细胞周期阻滞在S+G2/M期。〖HT5W〗结论〖HT5"SS〗: 磁性聚乳酸羟基乙酸氧化酚砷纳米微粒具有抑制肝癌细胞SMMC7721增殖的作用,处于G0/G1期的SMMC7721细胞可能为其药物作用的目标。 相似文献
908.
Purpose The aim of the study was to develop and evaluate a new method for the production of micro- and nanoparticles of poorly soluble
drugs for drug delivery applications.
Methods Fine particles of model compounds cholesterol acetate (CA), griseofulvin (GF), and megestrol acetate (MA) were produced by
extraction of the internal phase of oil-in-water emulsions using supercritical carbon dioxide. The particles were obtained
both in a batch or a continuous manner in the form of aqueous nanosuspensions. Precipitation of CA nanoparticles was used
for conducting a mechanistic study on particle size control and scale-up. GF and MA nanoparticles were produced in several
batches to compare their dissolution behavior with that of micronized materials. The physical analysis of the particles produced
was performed using dynamic light scattering (particle size), scanning electron microscopy (morphology), powder X-ray diffraction
(crystallinity), gas chromatography (residual solvent), and a dissolution apparatus.
Results Particles with mean volume diameter ranging between 100 and 1000 nm were consistently produced. The emulsion droplet size,
drug solution concentration, and organic solvent content in the emulsion were the major parameters responsible for particle
size control. Efficient and fast extraction, down to low parts-per-million levels, was achieved with supercritical CO2. The GF and MA nanoparticles produced were crystalline in nature and exhibited a 5- to 10-fold increase in the dissolution
rate compared with that of micronized powders. Theoretical calculations indicated that this dissolution was governed mainly
by the surface kinetic coefficient and the specific surface area of the particles produced. It was observed that the necessary
condition for a reliable and scalable process was the sufficient emulsion stability during the extraction time.
Conclusion The method developed offers a viable alternative to both the milling and constructive nanoparticle formation processes. Although
preparation of a stable emulsion can be a challenge for some drug molecules, the new technique significantly shortens the
processing time and overcomes the current limitations of the conventional precipitation techniques in terms of large waste
streams, product purity, and process scale-up. 相似文献
909.
纳米活性炭吸附丝裂霉素C腹腔化疗的实验研究 总被引:17,自引:1,他引:16
目的探讨新型淋巴靶向制剂吸附丝裂霉素C纳米活性炭(MMC—ACNP)的抗胃癌转移和抗复发作用。方法制备MMC-ACNP并检测其毒性;建立裸鼠人胃癌腹腔种植瘤模型;将48只裸鼠分为6组:生理盐水对照组、高剂量MMC组和低剂量MMC组、高剂量MMC-ACNP组、中剂量MMC—ACNP组和低剂量MMC—ACNP组,腹腔给药。给药4周后进行血液学检查,观察裸鼠体重及肿瘤播散和生长情况。结果MMC—ACNP小鼠腹腔注射半数敛死量(LD50)为46.80mg/kg,MMC小鼠腹腔注射LD50为9.33mg/kg。高剂量MMC组裸鼠体重增长缓慢,血小板显著减少,其他各组未见异常。在MMC剂量相同的情况下,MMC—ACNP的毒副作用明显低于MMC,其抑制肿瘤播散和生长的作用明显高于MMC。微小炭粒携带MMC进入肿瘤细胞核,有助于增强抑瘤效果。结论MMC-ACNP选择性高,毒副作用低,具有良好的临床应用前景。 相似文献
910.