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81.
豚鼠内耳磁微粒栓塞缺血模型初探   总被引:3,自引:0,他引:3  
OBJECTIVE: To set up an inner ear ischemic model in guinea pig with ferromagnetic embolism. METHODS: A magnet was fitted in the external auditory canal and carbonyl iron filings (1%, 1 ml/kg) was injected into jugular, then the inner ear vessels were obstructed by ferromagnetic spheres. Cochlear blood flow (CBF) and number of red blood cells in the stria vessels were used to detect the model's ischemia of cochleae. The slice of temple bone and basal membrane stained by silver nitrate were used for inner ear's histopathological observations. RESULTS: The iron spheres were amassed in the one and two-day-later's model of inner ear vessels, which resulted in embolism. The number of red blood cells in the stria vessels decreased and then recovered to normal level after 4 days, but the CBF decreased to 50% +/- 10% of basic level immediately and recovered to 99% +/- 41% 4 days later. Scattered lesion of out hair cell cilium could be seen in cochleae in eight-day-later's model, and degenerations in different degree were found in vascular stria. CONCLUSION: The methods of inner ear ischemic model with ferromagnetic embolism could be practical and the decrease of CBF was reversible, so it may be an ideal model for studying some ischemic inner ear diseases and evaluating the effects of therapeutic drugs.  相似文献   
82.
本文报道给家兔注入不同剂量的~3H-α-第二丁基对羟基苄醇,观察该药在其体内的药物动力学。结果表明,血中分布相快,消除相慢,消除半衰期T_1/1β为12h。经F值检验和理论计算值与实测值的契合程度比较,表明该药在兔体内的运转符合二室开放模型的动力学方程。  相似文献   
83.
The promoting effect of the Chinese medicinal herb, Wikstroemia chamaedaphne and Tung oil extracts (WC and HHPA) on carcinoma of uterine cervix induced by HSV-2 or MCA in mice was studied. The results showed that WC and HHPA extracts were not carcinogenic themselves. After carcinogen HSV-2 and MCA treatment, WC and HHPA were added separately. The inducing rates by HSV-2 increased from 7.4% to 21.1% and 26.3%, those by MCA increased from 56.5% to 82.8% and 84.4%. There was a significant difference between the combined groups and groups with HSV-2 or MCA only. The experimental results suggest that these two kinds of extracts play a promoting effect on carcinogenesis. The relation between the carcinogenesis of uterine cervix or nasopharynx and WC or HHPA extracts is discussed.  相似文献   
84.
将动、静脉阻断法用于恒速灌流的在体山羊左肺,使其总压力降区分为动脉端、静脉端及中间段三部分。大肠杆菌内毒素主要升高肺静脉端压力降及肺毛细血管压;山莨菪碱可显著缓解内毒素所致的改变,但对正常肺血管各段压力降无明显影响。5-羟色胺主要升高肺动脉端压力降,对肺静脉端及毛细血管压无明显影响。去甲肾上腺素及组胺主要升高肺静脉端压力降及肺毛细血管压,但对肺动脉端无明显影响。去甲肾上腺素和组胺可能介导内毒素性肺动脉高压。  相似文献   
85.
86.
The effects of localized gamma-irradiation on the in vivo 31P NMR spectra of RIF-1 tumors grown subcutaneously in C3H/HeN mice have been examined before and during the week after treatment. Increases in the ratio of phosphocreatine (PCr) to inorganic phosphate (Pi) and in tumor pH, and decreases in the ratio of Pi to the beta phosphorus resonance of the nucleotide triphosphates (beta NTP) were observed in irradiated tumors. The time course of changes in the 31P spectrum following treatment was the opposite of the pattern during untreated growth, and the magnitude and duration of the changes increased with increasing radiation dose, decreasing clonogenic cell survival and increasing growth delay. To examine the possibility that nontherapeutic systemic effects of the tumor irradiation were responsible for the changes observed, a number of animals bearing two tumors were examined. One tumor on each mouse was selectively irradiated. Changes in tumor volume, Pi/beta NTP, PCr/Pi, the ratio of phosphomonoesters to beta NTP, and tumor pH were all significantly different in the treated compared to the untreated tumor on each animal, indicating that these changes in 31P NMR spectra were a response to radiation therapy and not a systemic response to radiation toxicity.  相似文献   
87.
E S Li 《中华医学杂志》1989,69(11):607-9, 42
The historical review and the necessity of establishment of the Chinese Classification of Diseases (CCD) and Coding System are described. The content, terms used for unified and standardized nomenclatures, coding system including diagnostic terms of traditional Chinese medicine and other codings are introduced. The utility of the CCD system in medical record face sheet management, national native medical statistics, consultative retrieval from terms and codes of diseases, the development and practical trial of ICD-9 CCD is also discussed. Finally, the position and prospect of CCD system in international informatics communication is emphasized.  相似文献   
88.
BACKGROUND: Deposition of proteins on surfaces of medical devices has been recognized to putatively relate to the process of regulation of biomaterial-associated complications by attachment of fibrin clots, eukaryotic cells, and microbes. The molecules adsorb to a varying extent, depending not only on the physicochemical properties of the biomaterial, but also on the composition of the host fluid. OBJECTIVE: Adsorption of proteins on catheters exposed both ex vivo and in vitro to dialysate of patients on peritoneal dialysis (PD) was studied. METHODS: Peritoneal dialysis effluent was collected from 5 patients with end-stage renal disease on continuous ambulatory PD. Tenckhoff catheters were obtained from 16 patients. Deposition of proteins on excised Tenckhoff catheters and tubing of different materials exposed to PD effluent in vitro was studied using 125iodine-labeled antibodies. Adhesion of Staphylococcus aureus and Staphylococcus epidermidis strains was quantified on tubing exposed to PD effluent in vitro. RESULTS: The presence of albumin, transferrin, immunoglobulin G, fibrinogen, fibronectin, von Willebrand factor, vitronectin, and thrombospondin was determined at various concentrations in PD effluent. All proteins analyzed were detected on PD catheters removed from patients. The extent of protein deposition on Tenckhoff catheters exposed to PD effluent, in vitro, rapidly reached a plateau and remained constant, as it did on polyvinyl chloride and polyethylene tubing. Adhesion of staphylococci was enhanced on Tenckhoff catheters exposed to PD effluent compared to unused PD solution. CONCLUSIONS: The data identify surface exposed proteins that may serve as adhesion sites for microbes on peritoneal catheters indwelled in patients undergoing PD.  相似文献   
89.
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   
90.
李红  强大平 《基层医学论坛》2006,10(21):975-977
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   
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