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91.
92.
目的探讨辅酶Q10氯化钠注射液在食管癌放疗中的疗效及毒副反应。方法选择本院2010年2月~2011年8月笔者所在科放疗的306例食管癌患者,随机分成对照组和治疗组各153例,两组患者均在模拟定位机下定位,采用XHA600直线加速器体外常规分割照射,治疗组153例在常规放疗基础上加用辅酶Q10氯化钠注射液500ml静滴,1次/d,直至放疗结束。对照组行常规放疗。结果经过放疗后,对照组完全缓解(CR)3例,占2.0%;部分缓解(PR)39例,占25.5%;无缓解(NR)111例,占72.5%;(CR+PR)42例,占27.5%。治疗组完全缓解(CR)9例,占5.9%;部分缓解(PR)87例,占56.9%;无缓解(NR)57例,占37.2%;(CR+PR)96例,占62.7%。两组比较差异有统计学意义(P〈0.05)。结论辅酶Q10氯化钠注射液在食管癌放疗中增敏作用良好,可以提高治疗效果,减少毒副作用的发生。  相似文献   
93.
Comparative studies on the irritation potential of 18 surfactants were performed using the same stock solution of surfactant for each study. The ocular irritation potential of surfactants was studied using the red blood cell test (RBC), the hen's egg test-chorioallantoic membrane (HET-CAM) and the Skinethic ocular tissue model. The skin irritation potential was assessed based on data obtained from human studies using a 24h epicutaneous patch test (ECT) and a soap chamber test (SCT). The same pH and active substance (AS) content for all surfactants tested was used depending on the test conducted. In general, clusters of substances with varying irritation potential were identified similarly by most tests. These results show that when using standardized test conditions in which pH and % AS are the same for each surfactant tested, there is a good correlation between the in vitro ocular irritation assays themselves as well as between the dermal and ocular irritation assays. In particular the RBC test seems to be not only highly predictive for ocular irritation (H(50)/DI) but also for dermal irritation and changes in barrier function (DI) induced by surfactants.  相似文献   
94.
循经感传治疗胸痹的临床研究   总被引:3,自引:0,他引:3  
应用声电针激发感传气至病所的方法治疗冠心病30例,临床疗效和心电图疗效均优于药物对照组(P<0.05)。循经感传治疗能显著改善患者的左心功能状态和心肌复极电位,降低血液粘度。动物实验表明,声电针"内关"穴区能明显减轻家兔急性缺血心肌超微结构损伤的程度,改善缺血心肌的心电图,其机理可能与包括心钠素在内的心脏内分泌系统参与的全身性调整有关。  相似文献   
95.
A patient is presented who had therapy-resistant epileptic seizures from the 7th day of life. Examination at the age of 17 months revealed a mentally retarded boy with epileptic seizures, generalised myoclonic contractions, and abnormal ocular movements. A cerebral CT scan showed central and cortical atrophy. Lactate levels in serum, cerebrospinal fluid and urine were elevated, the pyruvate level was raised in serum. A quadriceps muscle biopsy revealed aspecific morphologic signs of a myopathy. Biochemical analysis showed decreased substrate oxidation rates in the mitochondria associated with low rates of ATP production. Total and free carnitine levels were decreased. Investigation of the respiratory chain revealed a defect in the proximal part of respiratory chain revealed a defect in the proximal part of respiratory chain involving the region of coenzyme Q. Based on clinical and chemical data it is likely that the patient is suffering from a multi-system disorder.Abbreviations EEG electroencephalogram - CT computed tomography - CSF cerebrospinal fluid - Ap5A P, P5-di(adenosine-5-)pantaphosphate - BSA bovine serum albumin - CPT carnitine palmitoyltransferase - SCC succinate: cytochrome c oxidoreductase - SQ succinate:coenzyme Q oxidoreductase - DCPIP 2,6-dichlorophenol indophenol This investigation is part of the research program Disorders of the Neuromuscular System  相似文献   
96.
97.
The potential threat of biological warfare with a specific agent is proportional to the susceptibility of the population to that agent. Preventing disease after exposure to a biological agent is partially a function of the immunity of the exposed individual. The only available countermeasure that can provide immediate immunity against a biological agent is passive antibody. Unlike vaccines, which require time to induce protective immunity and depend on the host's ability to mount an immune response, passive antibody can theoretically confer protection regardless of the immune status of the host. Passive antibody therapy has substantial advantages over antimicrobial agents and other measures for postexposure prophylaxis, including low toxicity and high specific activity. Specific antibodies are active against the major agents of bioterrorism, including anthrax, smallpox, botulinum toxin, tularemia, and plague. This article proposes a biological defense initiative based on developing, producing, and stockpiling specific antibody reagents that can be used to protect the population against biological warfare threats.  相似文献   
98.
Autoschizis: a novel cell death   总被引:10,自引:0,他引:10  
Vitamin C (VC) and vitamin K(3) (VK(3)) administered in a VC:VK(3) ratio of 100:1 exhibit synergistic antitumor activity and preferentially kill tumor cells by autoschizis, a novel type of necrosis characterized by exaggerated membrane damage and progressive loss of organelle-free cytoplasm through a series of self-excisions. During this process, the nucleus becomes smaller, cell size decreases one-half to one-third of its original size, and most organelles surround an intact nucleus in a narrow rim of cytoplasm. While the mitochondria are condensed, tumor cell death does not result from ATP depletion. However, vitamin treatment induces a G(1)/S block, diminishes DNA synthesis, increases H(2)O(2) production, and decreases cellular thiol levels. These effects can be prevented by the addition of catalase to scavenge the H(2)O(2). There is a concurrent 8- to 10-fold increase in intracellular Ca(2+) levels. Electrophoretic analysis of DNA reveals degradation due to the caspase-3-independent reactivation of deoxyribonuclease I and II (DNase I, DNase II). Redox cycling of the vitamins is believed to increase oxidative stress until it surpasses the reducing ability of cellular thiols and induces Ca(2+) release, which triggers activation of Ca(2+)-dependent DNase and leads to degradation of DNA. Recent experiments indicate that oral VC:VK(3) increases the life-span of tumor-bearing nude mice and significantly reduces the growth rate of solid tumors without any significant toxicity by reactivating DNase I and II and inducing autoschizis. This report discusses the mechanisms of action employed by these vitamins to induce tumor-specific death by autoschizis.  相似文献   
99.
BACKGROUND AND OBJECTIVES: We investigated the mechanism and characteristics of porcine myocardium tissue ablation in vitro with nanosecond 1,064- and 532-nm pulsed lasers at laser intensities up to approximately 5.0 GW/cm(2). Particular attention was paid to study the influence of the laser-induced plasma on the ablation characteristics. The applicability of these two lasers to transmyocardial laser revascularization (TMLR) was discussed. STUDY DESIGN/MATERIALS AND METHODS: Porcine myocardium tissue samples were irradiated with 1,064- and 532-nm, Q-switched Nd:YAG laser pulses, and the ablation depths were measured. The temporal profiles of the laser-induced optical emissions were measured with a biplanar phototube. For the ablated tissue samples, histological analysis was performed with an optical microscope and a polarization microscope. RESULTS: The ablation efficiency at 1,064 nm was higher than that at 532 nm. The ablation threshold at 1,064 nm (approximately 0.8 GW/cm(2)) was lower than that at 532 nm (approximately 1.6 GW/cm(2)), in spite of the lower absorption coefficient being expected at 1,064 nm. For the 1,064-nm laser-ablated tissues, thermal damage was very limited, while damage presumably caused by the mechanical effect was observed in most of the cases. For the 1,064-nm laser ablation, the ablation threshold was equal to the threshold of the laser-induced optical emission (approximately 0.8 GW/cm(2)), while for the 532-nm laser ablation, the optical emission threshold ( approximately 2.4 GW/cm(2)) was higher than the ablation threshold. CONCLUSIONS: We considered that for the 1,064-nm laser ablation, the tissue removal was achieved through a photodisruption process at laser intensities of > approximately 0.8 GW/cm(2). At laser intensities of > 3.0 GW/cm(2), however, the ablation efficiency decreased; this can be attributed to the absorption of incoming laser pulses by the plasma. For the 532-nm laser ablation, the tissue removal was achieved through a photothermal process at laser intensities of > approximately 1.6 GW/cm(2). At laser intensities of > 2.4 GW/cm(2), a photodisruption process may also contribute to the tissue removal, in addition to a photothermal process. With regard to the ablation rates, the 1,064-nm laser was more suitable for TMLR than the 532-nm laser. We concluded that the 1,064-nm Q-switched Nd:YAG laser would be a potential candidate for a laser source for TMLR because of possible fiber-based beam delivery, its compact structure, cost effectiveness, and easy maintenance. Animal trials, however, have to be carried out to evaluate the influence of the tissue damage.  相似文献   
100.
After 1 week of flu-like illness, a 64-year-old man developed rapidly progressive mononeuritis multiplex involving the right arm and both legs. Serologic studies identified Coxiella burnetii as the cause of the febrile disease (Q fever). Fourteen days doxycycline treatment (200 mg daily) induced rapid and complete recovery. After 6 months, flu-like symptoms, weakness and hypalgesia of the right leg reappeared. Antibody titers again identified Q fever. Doxycycline was re-established and induced prompt recovery. Q fever has been associated with various neurologic complications such as meningoencephalitis, cerebellitis, optic neuritis or polyneuroradiculitis. This is the first report on Q fever related mononeuritis multiplex. Prolonged antibiotic treatment may be required to prevent relapsing infection from the resistant bacterium.  相似文献   
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