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11.
蔡道 《中国新药与临床杂志》1992,(4)
对慢性阻塞性肺气肿(简称慢阻肺)患者20例(男13例,女7例;年龄53±7a)采用硝苯啶10-15mg,tid,po×2wk,后改为5mg,tid,维持用药,总有效率95%,副作用轻微。另设24例慢阻肺患者(男17例,女7例,年龄52±6a)采用氨茶碱0.1-0.2g,tid,po,×2wk,总有效率71%,其中4例因副作用而停药。2组疗效比较无显著差别。 相似文献
12.
M T Dao J P Villeneuve 《Clinical and investigative medicine. Médecine clinique et experimentale》1988,11(1):6-9
Triamterene is a potassium-sparing diuretic used in patients with cirrhosis for the treatment of ascites. It is extensively metabolized by the liver and is subject to an important first-pass effect after oral dosing. We examined the disposition and diuretic effect of triamterene after repeated oral administration (200 mg daily for 10 days) in 7 healthy controls and 6 patients with cirrhosis and ascites. In the controls the average plasma concentration of triamterene during a dosage interval was 45 +/- 8 ng/ml and that of hydroxy-triamterene sulfate, an active metabolite of triamterene, was 967 +/- 177 ng/ml. In the cirrhotics, the mean concentration of triamterene was 586 +/- 126 ng/ml (a 13-fold increase as compared with the controls) and that of hydroxy-triamterene sulfate was 747 +/- 502 ng/ml. Sodium excretion was correlated with hydroxy-triamterene sulfate levels in the controls (r = 0.81), but in the cirrhotics the diuretic response was correlated with basal sodium excretion (r = 0.86) and was not related to either triamterene or hydroxy-triamterene plasma concentrations. Our results indicate that chronic treatment with triamterene in patients with cirrhosis and ascites results in markedly elevated plasma levels, but these changes do not have a major influence on the magnitude of the diuretic response. 相似文献
13.
基于Lyapnuov泛函方法,研究了满足匹配条件的不确定性时滞系统的鲁棒稳定性及具有稳定度β〉0鲁棒稳定性,给出了已有结果不能推出的新判据。这些新判据对已有结果难以使用的情况下也可有是有效的,或有时减少了已有结果的保守性。 相似文献
14.
火器伤后胸心异物存留 总被引:8,自引:0,他引:8
目的:探讨火器伤后胸心异物存留摘除的指征、时机、方法及结果。方法:回顾性分析了39例火器伤后胸心异物存留摘除者的一般资料、临床表现、不同处理方法的选择及效果。结果:19例患者早期因凝固性血胸及肺持续漏气伴异物存留或异物存留伴胸腔及心包腔化脓性感染,在开胸清创时做了异物摘除;另20例患者为胸伤伤情恢复后单纯异物存留,因异物位于肺门、心脏及大血管旁或远期并发症等,而后期开胸异物摘除。结论:火器性胸部穿透伤后,因异物本身或其他原因所致早期并发症者,应在开胸清创的同时摘除异物;胸伤伤情恢复而单纯胸心异物存留,应选择性摘除或因并发远期并发症而摘除。 相似文献
15.
Dao Yin Xie Stefan Hassenstein Martin Oberhoff Hartmut Hanke Andreas Baumbach Kristian Hohla Karl Konstantin Haase Karl Rüdiger Karsch 《Lasers in surgery and medicine》1993,13(6):618-624
A modified exeimer laser energy delivery system was used to irradiate 100 segments of normal and fibrous aorta in vitro. The laser beam was scanned into 8 fiber bundles consisting of 50 fibers each resulting in a reduction of the applied pulse energy. The total repetition rate was increased to 150 Hz in order to keep the repetition rate per fiber bundle close to 20 Hz and to minimize thermal injury. The results demonstrate that effective ablation (etch rate per 8 pulses > 2.0 μm) occurred at an energy fluency of 50 mJ/mm2 in both normal and fibrous aorta. Tissue damage (carbonization, tissue separation, fissures, cracks, and vacuolization) was in a range of 100 ± 28 to 152 ± 30 μm for normal aorta and in a range of 57 ± 35 to 110 ± 39 μm for fibrous aorta. We conclude that effective ablation of normal and fibrous human aorta can be achieved by the application of smooth excimer laser coronary angioplasty. This improvement of excimer laser technology may result in a reduction of shock wave- and cavitation-induced damage leading to a reduction of tissue injury. However, this awaits further in vitro and in vivo confirmation. © 1993 Wiley-Liss, Inc. 相似文献
16.
羊膜建库及其临床应用研究 总被引:3,自引:0,他引:3
目的 :制备与保存羊膜 (Amnioticmembrane,AM ) ,为临床移植治疗眼表泪液 (Ocularsur face&Teardisease ,OSTD)提供新鲜羊膜 (Freshamnioticmembrane ,FSAM )、冻干羊膜 (Frozenam nioticmembrane ,FZAM )并观察其眼表重建的特点与临床疗效。方法 :采用目前国际公认的羊膜制备与保存方法 ,制备FSAM、FZAM并进行保存研究 ,经组织染色和电子显微镜检查 ,观察保存羊膜的形态及其活性 ;并将FSAM、FZAM应用于 12例OSTD患者 ,行患眼FSAM或FZAM移植术。通过术后印迹细胞学追踪观察移植后AM上皮细胞存活与移行、替代时间 ,评估AM移植重建眼表的临床疗效。结果 :FSAM、FZAM在光镜和电镜下均与正常球结膜组织结构相近 ,主要结构为胶原纤维和网状纤维。 12例OSTD患者行羊膜移植术 (Amnioticmembranetransplantation ,AMT)后均未见明显急性排斥反应 ,术后 1~ 2周可见少量新生血管长入植片 ,AMT后印迹细胞学追踪检查 ,术后 3个月为阴性 ,4个月出现阳性反应。所有患者术后随访 5~ 18个月 ,平均 11个月 ,AM在术后 4~ 9个月逐渐溶解、消失 ,移植区眼表的色泽与结构基本恢复正常。结论 :FSAM、FZAM是目前理想的结膜替代材料并可有效地用于重建角、结膜表面 ,减轻炎症反应 ,减少新生血管的生成 ,抑制纤维组织增生 ,防止 相似文献
17.
Genetic diversity among clinical isolates of Acremonium strictum determined during an investigation of a fatal mycosis 总被引:1,自引:0,他引:1
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Novicki TJ LaFe K Bui L Bui U Geise R Marr K Cookson BT 《Journal of clinical microbiology》2003,41(6):2623-2628
Primarily saprophytic in nature, fungi of the genus Acremonium are a well-documented cause of mycetoma and other focal diseases. More recently, a number of Acremonium spp. have been implicated in invasive infections in the setting of severe immunosuppression. During the course of routine microbiological studies involving a case of fatal mycosis in a nonmyeloablative hematopoietic stem cell transplant patient, we identified a greater-than-expected variation among strains previously identified as Acremonium strictum by clinical microbiologists. Using DNA sequence analysis of the ribosomal DNA intergenic transcribed spacer (ITS) regions and the D1-D2 variable domain of the 28S ribosomal DNA gene (28S), the case isolate and four other clinical isolates phenotypically identified as A. strictum were found to have <99% homology to the A. strictum type strain, CBS 346.70, at the ITS and 28S loci, while a sixth isolate phenotypically identified only as Acremonium sp. had >99% homology to the type strain at both loci. These results suggest that five out of the six clinical isolates belong to species other than A. strictum or that the A. strictum taxon is genetically diverse. Based upon these sequence data, the clinical isolates were placed into three genogroups. 相似文献
18.
Multimers of soluble major histocompatibility complex class I and II molecules have proven to be useful reagents in quantifying and following specific T cell populations. This study describes the design, generation, and characterization of a novel, single chain I-A(b) molecule which utilizes a unique linker derived from the murine invariant chain. A fragment of the invariant chain, residues 58-85, binds to a region proximal to the class II peptide binding groove and stabilizes occupancy of the class II invariant chain-associated peptide. We have utilized this fragment, replacing CLIP with the Ealpha peptide sequence, to lock the attached peptide into the class II binding groove. The single chain I-A(b) molecule was recognized by a panel of conformation-sensitive, I-A(b)-specific, monoclonal antibodies. Membrane-bound and soluble forms of the single chain I-A(b) stimulated an antigen-specific T cell hybridoma, and tetramers made from soluble monomers stained these cells. The unique features of this molecule may be useful in the design of recombinant T cell receptor ligands containing peptides with low affinity for MHC. 相似文献
19.
Yang JQ Chun T Liu H Hong S Bui H Van Kaer L Wang CR Singh RR 《European journal of immunology》2004,34(6):1723-1732
Mechanisms responsible for the development of autoimmune skin disease in humans and animal models with lupus remain poorly understood. In this study, we have investigated the role of CD1d, an antigen-presenting molecule known to activate natural killer T cells, in the development of inflammatory dermatitis in lupus-susceptible MRL-lpr/lpr mice. In particular, we have established MRL-lpr/lpr mice carrying a germ-line deletion of the CD1d genes. We demonstrate that CD1d-deficient MRL-lpr/lpr mice, as compared with wild-type littermates, have more frequent and more severe skin disease, with increased local infiltration with mast cells, lymphocytes and dendritic cells, including Langerhans cells. CD1d-deficient MRL-lpr/lpr mice had increased prevalence of CD4(+) T cells in the spleen and liver and of TCR alpha beta (+)B220(+) cells in lymph nodes. Furthermore, CD1d deficiency was associated with decreased T cell production of type 2 cytokines and increased or unchanged type 1 cytokines. These findings indicate a regulatory role of CD1d in inflammatory dermatitis. Understanding the mechanisms by which CD1d deficiency results in splenic T cell expansion and cytokine alterations, with increased dermal infiltration of dendritic cells and lymphocytes in MRL-lpr/lpr mice, will have implications for the pathogenesis of inflammatory skin diseases. 相似文献
20.
IMPT1, an imprinted gene similar to polyspecific transporter and multi- drug resistance genes 总被引:5,自引:1,他引:5
Dao D; Frank D; Qian N; O'Keefe D; Vosatka RJ; Walsh CP; Tycko B 《Human molecular genetics》1998,7(4):597-608
Human chromosome 11p15.5 and distal mouse chromosome 7 include a
megabase-scale chromosomal domain with multiple genes subject to parental
imprinting. Here we describe mouse and human versions of a novel imprinted
gene, IMPT1 , which lies between IPL and p57 KIP2 and which encodes a
predicted multi-membrane-spanning protein similar to bacterial and
eukaryotic polyspecific metabolite transporter and multi- drug resistance
pumps. Mouse Impt1 and human IMPT1 mRNAs are highly expressed in tissues
with metabolite transport functions, including liver, kidney, intestine,
extra-embryonic membranes and placenta, and there is strongly preferential
expression of the maternal allele in various mouse tissues at fetal stages.
In post-natal tissues there is persistent expression, but the allelic bias
attenuates. An allelic expression bias is also observed in human fetal and
post-natal tissues, but there is significant interindividual variation and
rare somatic allele switching. The fact that Impt1 is relatively repressed
on the paternal allele, together with data from other imprinted genes,
allows a statistical conclusion that the primary effect of human chromosome
11p15.5/mouse distal chromosome 7 imprinting is domain-wide relative
repression of genes on the paternal homolog. Dosage regulation of the
metabolite transporter gene(s) by imprinting might regulate placental and
fetal growth.
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