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Fabrication of porous hollow silica nanoparticles and their applications in drug release control. 总被引:11,自引:0,他引:11
Preparation and characterization of porous hollow silica nanoparticles (PHSN) for controlled release applications were investigated. Through orthogonally designed experiments, the optimal synthesis conditions for the preparation of PHSN were obtained and the produced PHSN were characterized by BET, SEM, TEM and IR. Scanning and transmission electron microscopy images revealed their hollow shell-core structure and also demonstrated that the size and shape of PHSN are determined by the templating CaCO3 nanoparticles. The produced PHSN were applied as a carrier to study the controlled release behaviors of Brilliant Blue F (BB), which was used as a model drug. Being loaded into the inner core and on the surfaces of the nanoparticles, BB was released slowly into a bulk solution for about 1140 min as compared to only 10 min for the normal SiO2 nanoparticles, thus exhibited a typical sustained release pattern without any burst effect. In addition, higher BET of the carriers, lower pH value and lower temperature prolonged BB release from PHSN, while stirring speed showed little influence on the release behavior. It showed that PHSN have a promising future in controlled drug delivery applications. 相似文献
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本文采用实验研究方法,通过对大鼠运动后红细胞数量,Hb浓度及体重等一般情况的检测,拟对其施加不同负荷的训练,观察训练后大鼠红细胞膜流动性及红细胞膜脂质成分的变化,进一步讨论运动后红细胞功能及机体机能所发生的变化。实验结果表明,小负荷的运动训练通过改善RBCM脂质组成,增加p/c比值、增强其抗氧化能力等增加RBCM流动性,使红细胞的变形能力增加,有利于其运氧功能的发挥。大负荷训练后RBCM流动性下降,提示不同负荷的运动训练会引起机体产生不同的变化,进而导致机体运动水平上的差异,整体携氧能力下降。 相似文献
25.
体重指数、腰围、腰臀比与血压、血糖、血脂关系的探讨 总被引:1,自引:1,他引:0
目的 探讨体重指数(BMI)、腰围(WC)、腰臀比(WHR)与代谢性因素的关系.方法 对镇江市居民基线资料的1108例对象按BMI、WC、WHR分组.在正常体重、超重、肥胖;腰围正常、腰围过大;腰臀比正常、腰臀比过大各组中,比较收缩压(SBP)、舒张压(DBP)、血糖(FBG)、总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)的水平.结果 不论男性女性组,超重肥胖、腰围过大组,血压、血糖、血脂水平与正常组比较均明显升高;腰臀比过大组与正常组比较,男性组TG、FBG明显升高;HDL-C明显降低;女性组TG、FBG、SBP明显升高,HDL-C明显降低.结论 BMI、WC、WHR指标与代谢性因素密切相关;BMI、WC在提示肥胖程度方面优于WHR指标. 相似文献
26.
Chang Hyun Lee Jung-Gi Im Jin Mo Goo Hyun Ju Lee Sung-Tae Hong Cheng Hua Shen Doo Hyun Chung Kyu Ri Son Jung Min Chang Hong Eo 《Korean journal of radiology》2007,8(5):372-381
OBJECTIVE: To investigate the serial CT findings of Paragonimus westermani infected dogs and the microscopic structures of the worm cysts using Micro-CT. MATERIALS AND METHODS: This study was approved by the committee on animal research at our institution. Fifteen dogs infected with P. westermani underwent serial contrast-enhanced CT scans at pre-infection, after 10 days of infection, and monthly thereafter until six months for determining the radiologic-pathologic correlation. Three dogs (one dog each time) were sacrificed at 1, 3 and 6 months, respectively. After fixation of the lungs, both multi-detector CT and Micro-CT were performed for examining the worm cysts. RESULTS: The initial findings were pleural effusion and/or subpleural ground-glass opacities or linear opacities at day 10. At day 30, subpleural and peribronchial nodules appeared with hydropneumothorax and abdominal or chest wall air bubbles. Cavitary change and bronchial dilatation began to be seen on CT scan at day 30 and this was mostly seen together with mediastinal lymphadenopathy at day 60. Thereafter, subpleural ground-glass opacities and nodules with or without cavitary changes were persistently observed until day 180. After cavitary change of the nodules, the migratory features of the subpleural or peribronchial nodules were seen on all the serial CT scans. Micro-CT showed that the cyst wall contained dilated interconnected tubular structures, which had communications with the cavity and the adjacent distal bronchus. CONCLUSION: The CT findings of paragonimiasis depend on the migratory stage of the worms. The worm cyst can have numerous interconnected tubular channels within its own wall and these channels have connections with the cavity and the adjacent distal bronchus. 相似文献
27.
TUVP手术时间对血红蛋白及电解质的影响 总被引:2,自引:0,他引:2
目的 了解经尿道前列腺汽化电切手术时间对血红蛋白及血清电解质的影响。方法 对64例经尿道前列腺汽化电切术患按手术时间分组,观察手术前后血红蛋白及血清电解质的变化。结果 手术时间对血清电解质的降低有的影响,对血红蛋白降低的影响不显。结论 减少TUR综合征的关键是要操作熟练,缩短手术时间及手术中注意止血。 相似文献
28.
BACKGROUND: Cutaneous metastasis from adenoid cystic carcinoma of the salivary gland is very rare. OBJECTIVE: To present an unusual case of cutaneous metastasis from adenoid cystic carcinoma of the right parotid gland. METHODS: A 63-year-old woman with multiple subcutaneous nodules on the abdomen and a gradually enlarged mass over the right parotid area was examined. A skin biopsy was taken from one of the abdominal nodules. RESULT: Skin biopsy demonstrated the characteristic histopathologic features of metastatic adenoid cystic carcinoma. A subsequent computerized tomography of the head and neck revealed a huge soft tissue mass involving the right parotid gland. Computerized tomography of the chest revealed extensive nodular pleural thickening, and pleural biopsy also showed typical histopathologic features of metastatic adenoid cystic carcinoma. All of these results are consistent with the diagnosis of an adenoid cystic carcinoma of the right parotid gland with disseminated metastases. CONCLUSION: We report a rare case of cutaneous metastasis from adenoid cystic carcinoma of the right parotid gland. The presentation of cutaneous metastasis is often nonspecific and may mimic benign lesions. Subcutaneous nodules that are rapidly developing or eruptive, are rapidly growing and have stony hardness in nature, have pain or tenderness, and have nonhealing ulceration remind us of the possibility of cutaneous metastases. Dermatologists and dermatologic surgeons should keep the diagnosis of cutaneous metastasis in mind and always perform skin biopsy when encountering these lesions. 相似文献
29.
目的 探讨血清肌钙蛋白Ⅰ(cTn-I)对急性脑血管病(ACVD)后心肌损伤的诊断价值.方法 检测160例ACVD患者入院后24h内、3d、7d的血清cTn-I和肌酸激酶同工酶(CK-MB),比较不同病程、不同类型、不同病情程度ACVD患者血清cTn-I和CK-MB的测定结果,观察预后与cTn-I、CK-MB的关系.结果 病后24h内和7d血清cTn-I较CK-MB的阳性率高;脑出血和重症患者病后7d cTn-I仍增高;病后30d内死亡者的cTn-I和CK-MB增高比例高于存活者.结论 血清cTn-I对ACVD后心肌损伤的检测具有比CK-MB更高的敏感性、特异性和更宽的诊断窗口. 相似文献
30.
Disseminating tumor cells and their interactions with leukocytes visualized in the brain. 总被引:3,自引:0,他引:3
Brain tumors are increasingly prevalent. Recent advances focus attention on individual, disseminated tumor cells that cannot be imaged or eliminated. Cells of the immune system may be ideally suited to attack individual tumor cells, but more basic understanding is needed. We describe a rat model, using the lacZ reporter gene, that allows identification of individual tumor cells, and tumor-leukocyte interactions in vivo. The model demonstrates how widely tumor can disseminate, without secondary tumorigenesis or recruitment of nonneoplastic cells. It demonstrates that leukocytes have access to disseminating tumor. Among its many applications, this work lays a foundation for developing cell-mediated immunotherapy against individual brain tumor cells. 相似文献