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51.
本文介绍了1种由BCM-80单板机到AppleⅡ微机的图象数据传输方法。这种方法以盒式磁带作为传输工具,并采用AppleⅡ的磁带记录格式将由BCM-80所采集的同位素扫描图象数据传送到AppleⅡ微机之中,进行分析处理,然后输出1幅静止的易于识别和诊断的图象。此种方法不需要增加任何硬件,具有简单、可靠、传输速度快等优点。 相似文献
52.
Leire García Maria Bu?uales Nejat Düzgüne? Conchita Tros de Ilarduya 《European journal of pharmaceutics and biopharmaceutics》2007,67(1):58-66
In this study, an efficient non-viral gene transfer system has been developed by employing polyethylenimine (PEI 800, 25 and 22kDa) and DOTAP and cholesterol (Chol) as lipids (lipopolyplex), at three different lipid/DNA molar ratios (2/1, 5/1 and 17/1) by using five different protocols of formulation. Condensation assays revealed that PEI of 800, 25 and 22kDa were very effective in condensing plasmid DNA, leading to a complete condensation at N/P ratios above 4. Addition of DOTAP/Chol liposomes did not further condense DNA. Increasing the molar ratio lipid/DNA in the complex resulted in higher positive values of the zeta-potential, while the particle size increased in some protocols, but not in others. High molecular weight PEI (800kDa) used in the formulation of lipopolyplexes lead to a bigger particle size, compared to that obtained with smaller PEI species, whether branched (25kDa) or linear (22kDa). These vectors were also highly effective in protecting DNA from attack by DNAse I. Transfection activity was maximal by using protocols 3 and 4 and a lipid/DNA molar ratio of 17/1. These complexes showed high efficiency in gene delivery of DNA to liver cancer cells, even in the presence of high concentration of serum (60% FBS). On the other hand, complexes formed with linear PEI (22kDa) were more effective than lipopolyplexes containing branched PEI (800 or 25kDa). The complexes resulted to be much more efficient than conventional lipoplexes (cationic lipid and DNA) and polyplexes (cationic polymer and DNA). The same behaviour was observed for complexes prepared in the presence of the therapeutic gene pCMVIL-12. Toxicity assays revealed a viability higher than 80% in all cases, independently of the protocol, molar ratio (lipid/DNA), molecular weight and type of PEI. 相似文献
53.
Jean-Fran?ois Ghersi-Egea Nathalie Strazielle Audrey Murat Anne Jouvet Annie Buénerd Marie-Fran?oise Belin 《Journal of cerebral blood flow and metabolism》2006,26(9):1165-1175
The choroid plexuses (CPs) form a protective interface between the blood and the ventricular cerebrospinal fluid (CSF). To probe into the pathways by which CPs provide brain protection, we sought to evaluate the efficiency of glutathione conjugation in this barrier as a mechanism to prevent the entry of blood-borne electrophilic, potentially toxic compounds into the CSF, and we investigated the fate of the resulting metabolites. Rat CPs, as well as human CPs from both fetal and adult brains, displayed high glutathione-S-transferase activities. Using an in vitro model of the blood-CSF barrier consisting of choroidal epithelial cells cultured in a two-chambered device, we showed that glutathione conjugation can efficiently prevent the entry of 1-chloro-2,4-dinitrobenzene (CDNB) into the CSF, a model for electrophilic compounds. The duration of this enzymatic protection was set by the concentration of CDNB to which the epithelium was exposed, and this barrier effect was impaired only on severe epithelial intracellular glutathione and cysteine depletion. The conjugate was excreted from the choroidal cells in a polarized manner, mostly at the blood-facing membrane, via a high-capacity transport process, which is not a rate-limiting step in this detoxification pathway, and which may involve transporters of the ATP-binding cassette c(Abcc) and/or solute carrier 21 (Slc21) families. Supplying the choroidal epithelium at the blood-facing membrane with a therapeutically relevant concentration of N-acetylcysteine sustained this neuroprotective effect. Thus, glutathione conjugation at the CP epithelium coupled with the basolateral efflux of the resulting metabolites form an efficient blood-CSF enzymatic barrier, which can be enhanced by pharmacologically increasing glutathione synthesis within the epithelial cells. 相似文献
54.
犬海水中火器伤后早期血流动力学变化 总被引:3,自引:0,他引:3
Hui Meng Hong Shen Gao-wang Liu Tian-ling Zhu Jun-xin Zhang Zeng-rong Wu Hai-ji Bu 《第一军医大学学报》2004,24(5):493-496
OBJECTIVE: To investigate the hemodynamic changes in the early stages of gunshot wound of dogs in seawater for exploring early treatment protocol. METHOD: Fourteen conventional Beagles models undergoing gunshot wound in seawater were used along with another 2 dogs receiving the wound on land to serve as control. After the dogs were rescued from the seawater, the respiration (R), heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), central venous pressure (CVP), pulmonary arterial wedge pressure (PAWP), and cardiac output (CO) were measured continuously in the early stages of the wound (53.62+/-12.19 min following injury), followed by statistical analysis of the results. RESULTS: Compared with the control group, the hemodynamic disturbance of the dogs receiving the wound in seawater was relatively severe during the first 15 min of the wound. The mortality tended to descend relevant to the position of the wounds, in the order of the head, chest, abdomen and limbs. CONCLUSIONS: Gunshot wound in seawater may cause severe hemodynamic changes, resulting in progressive dysfunction of circulation and high mortality rate. Early treatment should be targeted at hemodynamic stabilization in accordance to the characteristic changes during the early stages of the wound. 相似文献
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Engin Altinta? Dilek O?uz Sabite Ka?ar Yasemin Ozderin Orhan Sezgin Neslihan Inci Zengin 《The Turkish journal of gastroenterology》2004,15(1):49-52
Dydrogesterone, similar to women's natural progesterone, has been used in a wide range of gynecological conditions. Despite its widespread use, dydrogesterone-induced hepatotoxicity and dydrogesterone-induced hemolytic anemia have, to the best of our knowledge, never been reported previously. We describe a case of hepatitis and warm antibody hemolytic anemia due to dydrogesterone. 相似文献
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Mladen Miskulin Andrea Mikulin Hrvoje Klobucar Slobodan Kuvalja 《The Journal of foot and ankle surgery》2005,44(1):49-56
The purpose of this study was to review the clinical results of 5 patients who underwent repair of a chronic Achilles tendon rupture using a combination of peroneus brevis transfer and plantaris tendon augmentation. The technique belongs to the group of local tendon transfer procedures making use of the transferred peroneus brevis tendon as strengthening material together with the plantaris tendon as suturing material. There were 4 males and 1 female with an average age of 49.4 years and an average time to presentation postinjury of 19.8 weeks (range 5-40 wk). All patients underwent Cybex strength testing before and approximately 1 year after surgery. This testing demonstrated a postoperative improvement in peak plantarflexion torque (Newton-meters/body weight) in all cases. The peak torque of plantar flexion increased in all patients (range, 21%-410%). Four patients were found to have an increase of the dorsal flexors peak torque (range, 31%-290%), whereas one patient showed a decrease (-37%). No patient experienced wound closure complications, postoperative pain, or functional limitations. In spite the possibility of residual lateral ankle instability, we found this modification to be a valuable innovation that offers a very good functional result, low morbidity, technical advantages to the surgeon and, most important, a durable and satisfactory result for the patients. 相似文献