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231.
实施气管切开病人2种气道湿化方法的效果比较 总被引:1,自引:0,他引:1
目的:比较气管切开后气管内持续滴入湿化法与间断滴入湿化法湿化气道的效果.方法:将52例气管切开患者分成2组,甲组采用持续滴入湿化法,乙组采用间断滴入湿化法.结果:湿化24h后,甲组湿化满意率为86.2%,乙组为52.17%,湿化不足者乙组为8.7%,甲组为0.001%.结论:持续滴入湿化效果满意,肺部感染发生率低,不易形成痰栓,且能减轻护理工作量,值得临床推广应用. 相似文献
232.
治疗超声介导微泡造影剂实现辅助给药及治疗(如基因转染),成为超声研究中的热点。这种方法已经在体内和体外多种模型中实现,并可能为靶向个体化诊断和治疗开辟新的领域。本文就该技术的可能机制,研究现状以及研究前景作一综述。 相似文献
233.
肿瘤是目前世界上死亡率最高的疾病之一,手术、放化疗是目前治疗肿瘤的常用手段.但是肿瘤是一个多因素导致的疾病,必须从多方面考虑其治疗机制.靶向治疗是现阶段肿瘤治疗的新技术,可针对多种机制来抑制肿瘤的发生和发展或消除肿瘤.对此,相关研究者们已在肿瘤靶向治疗方面开展了大量的工作,为肿瘤的防治提供了参考依据。 相似文献
234.
Schwarz G 《Cellular and molecular life sciences : CMLS》2005,62(23):2792-2810
The molybdenum cofactor (Moco) forms the active site of all molybdenum (Mo) enzymes, except nitrogenase. Mo enzymes catalyze
important redox reactions in global metabolic cycles. Moco consists of Mo covalently bound to one or two dithiolates attached
to a unique tricyclic pterin moiety commonly referred to as molybdopterin (MPT). Moco is synthesized by an ancient and conserved
biosynthetic pathway that can be divided into four steps, according to the biosynthetic intermediates precursor Z (cyclic
pyranopterin monophosphate), MPT and adenylated MPT. In a fifth step modifications such as attachment of nucleotides, sulfuration
or bond formation between Mo and the protein result in different catalytic Mo centers. A defect in any of the steps of Moco
biosynthesis results in the pleiotropic loss of all Mo enzyme activities. Human Moco deficiency is a hereditary metabolic
disorder characterized by severe neurodegeneration resulting in early childhood death. Recently, a first substitution therapy
was established.
Received 17 June 2005; received after revision 18 August 2005; accepted 1 September 2005 相似文献
235.
Generation of the serine proteinase plasmin from the extracellular zymogen plasminogen can be catalyzed by either of two
other serine proteinases, the urokinase- and tissue-type plasminogen activators (uPA and tPA). The plasminogen activation
system also includes the serpins PAI-1 and PAI-2, and the uPA receptor (uPAR). Many findings, gathered over several decades,
strongly suggest an important and causal role for uPA-catalyzed plasmin generation in cancer cell invasion through the extracellular
matrix. Recent evidence suggests that the uPA system is also involved in cancer cell-directed tissue remodeling. Moreover,
the system also supports cell migration and invasion by plasmin-independent mechanisms, including multiple interactions between
uPA, uPAR, PAI-1, extracellular matrix proteins, integrins, endocytosis receptors, and growth factors. These interactions
seem to allow temporal and spatial reorganizations of the system during cell migration and a selective degradation of extracellular
matrix proteins during invasion. The increased knowledge about the plasminogen activation system may allow utilization of
its components as targets for anti-invasive therapy. 相似文献
236.
This paper proposes a stochastic prediction DEA model with undesirable outputs and simplifies the process using chance-constrained techniques in order to obtain an equivalent linear programming formulation. The existence and stability of the optimal solutions have been proved. And the model is used to describe and predict the efficiency of anti-HIV therapy in AIDS patients. 相似文献
237.
基因治疗及其研究进展 总被引:3,自引:0,他引:3
宋新强 《信阳师范学院学报(自然科学版)》2002,15(4):473-477
基因治疗作为一种新型的疾病治疗手段 ,正在广泛用于血友病、糖尿病、癌症、心血管病、爱滋病等多种疾病的治疗领域 .基因治疗的一般步骤包括 :目的基因的转移和目的基因的表达两个方面 .其中目的基因的导入和目的基因表达的精确调控是两个关键步骤 .新发展的还有反义疗法以及应用核酶进行基因治疗等 .本文就基因治疗的基本步骤、基因治疗的对象、方式及基因治疗的现状和前景作一个简单介绍 相似文献
238.
Bromelain: biochemistry, pharmacology and medical use 总被引:10,自引:0,他引:10
Maurer HR 《Cellular and molecular life sciences : CMLS》2001,58(9):1234-1245
Bromelain is a crude extract from the pineapple that contains, among other components, various closely related proteinases,
demonstrating, in vitro and in vivo, antiedematous, antiinflammatory, antithrombotic and fibrinolytic activities. The active
factors involved are biochemically characterized only in part. Due to its efficacy after oral administration, its safety and
lack of undesired side effects, bromelain has earned growing acceptance and compliance among patients as a phytotherapeutical
drug. A wide range of therapeutic benefits has been claimed for bromelain, such as reversible inhibition of platelet aggregation,
angina pectoris, bronchitis, sinusitis, surgical traumas, thrombophlebitis, pyelonephritis and enhanced absorption of drugs,
particularly of antibiotics. Biochemical experiments indicate that these pharmacological properties depend on the proteolytic
activity only partly, suggesting the presence of nonprotein factors in bromelain. Recent results from preclinical and pharmacological
studies recommend bromelain as an orally given drug for complementary tumor therapy: bromelain acts as an immunomodulator
by raising the impaired immunocytotoxicity of monocytes against tumor cells from patients and by inducing the production of
distinct cytokines such as tumor necrosis factor-α, interleukin (Il)-1β, Il-6, and Il-8. In a recent clinical study with mammary tumor patients, these findings could be partially confirmed. Especially
promising are reports on animal experiments claiming an antimetastatic efficacy and inhibition of metastasis-associated platelet
aggregation as well as inhibition of growth and invasiveness of tumor cells. Apparently, the antiinvasive activity does not
depend on the proteolytic activity. This is also true for bromelain effects on the modulation of immune functions, its potential
to eliminate burn debris and to accelerate wound healing. Whether bromelain will gain wide acceptance as a drug that inhibits
platelet aggregation, is antimetastatic and facilitates skin debridement, among other indications, will be determined by further
clinical trials. The claim that bromelain cannot be effective after oral administration is definitely refuted at this time.
Received 25 August 2000; received after revision 29 March 2001; accepted 30 March 2001 相似文献
239.
肿瘤治理新方法的研究现状与未来(Ⅱ):声动力化学在肿瘤治疗中的应用 总被引:1,自引:0,他引:1
详细介绍了声动力化学(SDCT)疗法的发展历史及肿瘤治疗的声动务化学原理,并介绍了肿瘤声动力化学疗法这一领域的最新动态。 相似文献
240.
Meso-tetrahydroxylphenyl chlorin (m-THPC) is one of the most efficient prospective sensitizers used in photodynamic therapy (PDT). ESR spectroscopy, fluorescence quenching experiments and cyclic voltammogram measurement were used to study its redox properties. The results showed that the ability of m-THPC generating superoxide radical anions was very strong, and the rate constant of m-THPC fluorescence quenching by oxygen kq (O2)=1.46×1010 mol-1·s-1. The values of fluorescence quen- ching rate constant of m-THPC by some other electron acceptors, such as methyl viologen (MV2+) and anthraquinone (An), were also measured. And they were kq (MV2+)=5.51×109 mol-1·s-1, kq (An)=7.81×109 mol-1·s-1. The oxidation potential of m-THPC was examined to be +0.62 V (vs. NHE) in acetonitrile. All these suggested that m-THPC should be a much stronger electron donor than photofrin, the currently used in clinical photodrug, and may react easily through electron transfer with biological matter to yield various radicals. So it seemed reasonable that the type Ⅰ reaction may play an important role in the high activity of m-THPC-PDT. 相似文献