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11.
12.
A nationwide laboratory-based surveillance system for invasive group A streptococcal (GAS) infections was conducted in The Netherlands from March 1992 until December 2003. Until 1996, all isolates submitted were evaluated clinically and demographically. During this period there was a transition from passive to active surveillance for some of the participating laboratories, corresponding to a national coverage of 50%. During active surveillance, participating laboratories submitted twice as many isolates from invasive GAS disease, whereas the relative submission of isolates representing very severe manifestations (toxic shock-like syndrome, fatality) did not increase. From 1997 onwards, invasiveness was defined solely on the basis of source of isolation (without clinical evaluation). During the period of microbiological and clinical evaluation, microbiological evaluation alone was found to be specific (> 99%), but had limited sensitivity (66%). Estimation of the true rate of invasive GAS disease should be based on an active surveillance system with inclusion of both microbiological and clinical data.  相似文献   
13.
Ischaemia-reperfusion injury (IRI) is of obvious relevance in situations where there is an interruption of blood supply to the gut, as in vascular surgery, or in the construction of free intestinal grafts. It is now appreciated that IRI also underlies the gut dysfunction that occurs in early shock, sepsis, and trauma. The events that occur during IRI are complex. However, recent advances in cellular biology have started to unravel these underlying processes. The aim of this review is to provide an outline of current knowledge on the mechanisms and consequences of IRI. Initially, IRI appears to be mediated by reactive oxygen metabolites and, at a later stage, by the priming and activation of polymorphonuclear neutrophils (PMN). Ischaemia-reperfusion injury can diminish the barrier function of the gut, and can promote an increase in the leakage of molecules (intestinal permeability) or the passage of microbes across the wall of the bowel (bacterial trans-location). Ischaemia-reperfusion injury to the gut can result in the generation of molecules that may also harm distant tissues.  相似文献   
14.
A brief overview is provided of the bioactivity of macrolides against a range of bacterial species. Topics considered include the cellular pharmacokinetics of uptake and efflux of these drugs and the importance of intra- or extracellular and cytoplasmic or granular location on their activity. Emphasis is placed on the importance of synergy between macrolides and host defenses, with drug accumulation producing modification of cellular function, such as enhancement of phagocytosis, and exocytosis of polymorphonuclear neutrophils. Such interaction may explain the activity of such agents against organisms which normally inhibit fusion of phagolysosomes.  相似文献   
15.
All-Union Surgical Research Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. N. Malinovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 112, No. 12, pp. 653–657, December, 1991.  相似文献   
16.
青黛颗粒抗炎、镇痛作用的实验研究   总被引:3,自引:0,他引:3  
目的 :通过对青黛颗粒抗炎、镇痛作用的实验研究 ,探讨该药治疗溃疡性结肠炎的作用机理。方法 :采用小鼠醋酸扭体法、大鼠棉球肉芽肿法和角叉菜胶所致大鼠足肿胀方法。结果 :青黛颗粒给药高、中、低剂量组和阳性对照药组均明显降低小鼠扭体次数 (P<0 .0 5~P<0 .0 1)。对大鼠棉球肉芽肿和大鼠足肿胀有显著的抑制作用 (P <0 .0 1~P <0 .0 0 1)。结论 :青黛颗粒分别对大鼠具有抗炎、对小鼠具有镇痛作用。且镇痛作用呈量效关系  相似文献   
17.
ABSTRACT. Two atypical cases of colitis due to cow's milk protein intolerance (CMPI) are reported, affecting preterm infants. One developed a toxic dilatation of the colon and responded well to a casein hydrolysate based feed. The second presented insidiously and failed to tolerate a casein hydrolysate, but responded well to a chicken-based modular feed.  相似文献   
18.
S. WAKI 《Parasite immunology》1994,16(11):587-591
The effects of administrating recombinant human granulocyte colony-stimulating factor (rhG-CSF) and passively transferring immune serum on infection with an attenuated variant of Plasmodium berghei XAT (Pb XAT), in severe combined immunodeficiency (SCID) mice were examined. In immune competent (C.B-17) mice, the attenuated parasite infection was inevitably self-resolving and degenerating forms inside erythrocytes appeared, coinciding with the drop in parasitaemia, whereas SCID mice were unable to control parasite growth and all the mice died. Continuous administration with rhG-CSF caused neutrophilic granulocytosis in both SCID and C.B-17 mice. The effect of rhG-CSF on the infection in C.B-17 mice was to suppress the course of the parasitaemia at an early phase whereas it had no effect in SCID mice. When immune serum was transferred on the day of infection, the prepatent period was prolonged two days in both SCID and C.B-17 mice. When administration with rhG-CSF was combined with transfer of immune serum, SCID mice showed four days delay in patency and degenerating parasites were seen during the course of parasitaemia, although the infection was ultimately fatal. C.B-17 mice similarly treated showed a seven day delay in the onset of the patent parasitaemia which was of a lesser magnitude and shorter in duration compared with control mice. On the other hand, when C.B-17 mice were splenectomized three weeks before infection and then treated with rhG-CSF and immune serum, no degenerating parasites were seen during the infection and all mice died with high parasitaemias. These results show that antibody-dependent neutrophil-mediated parasite killing may occur in the spleen of mice infected with P. berghei XAT.  相似文献   
19.
Objective: To reveal the relationship between the biological characteristics of pathogen and the pig-to-human spread of the epidemic and infectious disease in 1998 in East China. Methods: Epidemiological survey, pathological examination of pigs and patients, and pathogen isolation were performed. Results: The disease had a character of quick onset, serious symptoms, short course and high mortality. The clinical manifestations and pathological changes of the disease were high fever, sometimes with nausea, vomiting and diarrhea, then might develop to myositis, fascitis, DIC, multiple organ failure, shock and usually died in 2-3 d. Among 25 patients, 16 manifested clinically as streptococcal toxic shock syndromes and 9 streptococcal meningiocephalitis syndrome. The mortality was 81.25% and 11.11% respectively. Pathogenic bacteria isolated from diseased pigs and patients were found to have some common characteristics in morphology, staining and biological characters. Conclusion: The pathogen isolated from the blood of patients and pigs were identified as streptococci.  相似文献   
20.
异烟肼、利福平治疗肺结核致肝毒性易感基因的研究   总被引:2,自引:0,他引:2  
目的:探讨N-乙酰基转移酶(NAT2)基因型与异烟肼、利福平治疗肺结核致肝毒性的相关性。方法:通过聚合酶链反应-限制性片段长度多态性(PCR—RFLP)技术分析67例经利福平、异烟肼治疗后发生或未发生肝功能异常的肺结核患者NAT2基因多态性的部位、性质及发生率。结果:病例组和对照组857位密码子多态性分别是20.3%和7.1%,两组差异显著。结论:NAT2基因型与异烟肼和利福平所致肝毒性关系密切,其中857位密码子点突变可能是结核患者发生肝毒性的易感基因型之一。  相似文献   
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