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排序方式: 共有656条查询结果,搜索用时 31 毫秒
1.
Abstract A short-term oral administration of live Saccharomyces cerevisiae cells, strain Sillix Hansen DSM 1883, resulted in enhanced resistance of mice toward infections with K. pneumoniae, S. pneumoniae and S. pyogenes A produced by intranasal inoculation. Yeast pre-treatment also increased the efficacy of antibiotic therapy in bacterial infections and of antiviral drugs in viral infections. Yeast treatment of animals stimulated phagocytosis, activated the complement system and induced interferon which are likely to represent the main mechanisms of action whereby pretreatment of mice with live S. cerevisiae cells increases resistance to infection. It is concluded that preventive administration of live Saccharomyces cerevisiae cells should be used for increasing resistance to bacterial infections, in particular of the respiratory tract, or to viral infections, as well as an adjunct to antibiotic and antiviral drug therapy.  相似文献   
2.
PurposeTo define optimal planning target volume (PTV) margins for intensity modulated radiotherapy (IMRT) ± knee-heel support (KHS) in patients treated with adjuvant radiotherapy.MethodsComputed tomography (CT) scans ± KHS of 10 patients were taken before and at 3rd and 5th week of treatment, fused and compared with initial IMRT plans.ResultsA PTV margin of 15 mm in anteroposterior (AP) and superoinferior (SI) directions and 5 mm in lateral directions were found to be adequate without any difference between ± KHS except for the SI shifts in CTV-primary at the 3rd week. Five mm margin for iliac CTV was found to be inadequate in 10–20% of patients in SI directions however when 7 mm margin was given for iliac PTV, it was found to be adequate. For presacral CTV, it was found that the most striking shift of the target volume was in the direction of AP. KHS caused significantly less volume of rectum and bladder in the treated volume.ConclusionsPTV margin of 15 mm in SI and AP, and 5 mm in lateral directions for CTV-primary were found to be adequate. A minimum of 7 mm PTV margin should be given to iliac CTV. The remarkable shifting in presacral CTV was believed to be due to the unforeseen hip malposition of obese patients. The KHS seems not to provide additional beneficial effect in decreasing the shifts both in CTV-primary and lymphatic, however it may have a beneficial effect of decreasing the OAR volume in PTV margins.  相似文献   
3.
This is a literature review of 361 opportunistic fungal infections caused by the Zygomycetes. The clinical and laboratory diagnosis, pathogenesis, management, treatment, and outcome of infection are discussed. The Zygomycetes are a group of opportunistic fungi (orders Mucorales and Entomophthorales) which cause severe infections which may be fatal. Early clinical recognition, prompt diagnostic procedures, control of underlying disease and treatment with high doses of amphotericin B and aggressive surgery increases survival in an otherwise lethal infection.  相似文献   
4.
The general solution of the mathematical model of herd immunity to human helminth infections recently proposed by Anderson and May [3] is obtained. The numerical solution of a more accurate biological model is indistinguishable from the corresponding exact solution of a more tractable mathematical model. Computer simulations of some particular cases of this model support the notion that both ecological and immunological factors determine the observed convex patterns of age-prevalence and age-intensity curves of human helminth infections.This work was made thanks to the advise and support of Dr. Robert M. May while the author was Postdoctoral Fellow at Princeton University  相似文献   
5.
Serum copper and zinc levels were determined in 20 healthy women and in 100 women with gynecological tumors. Malignant and benign tumor cases were separated according to their postoperative, histopathological examinations. The stages of malignant and benign tumors were also established histologically. Seventy benign and 30 malignant genital tumors (carcinoma of cervix in situ, cervix, ovary endometrium, and vulva) of the patients were differentiated histopathologically. The serum Cu/Zn ratios of patients were increased significantly from the control group (0.32±0.35) to the benign group (1.22±0.63) and from the benign group to the malignant group (2.24±1.03). Nine of 30 malignant cases were determined as false negative (30%) and 15 of 70 benign cases were determined as false positive (14.2%) according to the serum Cu/Zn ratios of patients. Serum copper levels of 30 malignant and 10 benign tumor cases showed linear correlation with serum ceruloplasmin values.  相似文献   
6.
The incidence of lethal parasites in the larvae of a Tipula paludosa population was monitored for two seasons. The proportions of larvae infected with Tipula iridescent virus (TIV) and a tachinid insect were similar to those in previously studied populations, whereas the proportions of larvae infected with Tipula nuclear polyhedrosis virus (NPV) and a spore-forming bacterium (SFB) were higher. Conservative estimates of mortality due to these four agents were 10.7% in 1977–1978 and 7.7% in 1978–1979. The mean population density and the proportion of SFB-infected larvae were lower in 1978–1979 than in 1977–1978, while the proportion of NPV-infected larvae was higher. In 1979 the proportion of NPV-infected larvae was positively correlated with population density, which was highest in the wettest part of the study area. In both seasons the proportion of SFB-infected larvae was negatively correlated with population density. Larvae infected with the NPV or the SFB became pallid at an advanced stage of infection, but, although infected larvae were found throughout the larval period, pallid larvae were only found in the later part. It is suggested that larvae become infected in an early instar, then the infections slowly develop throughout the remainder of the larval period. Five larvae were found with mixed infections; four were infected with the SFB and NPV, while the fifth was infected with the SFB and TIV.  相似文献   
7.
IgG asymmetric antibodies are synthesized by the same cellular clones as the symmetric ones but appear in the immune response in different proportions. The evidence suggests that they are caused by asymmetric glycosylation on some IgG molecules in the Fab region. The cause of this is unknown but it could be speculated that there are cellular factors that induce glycosyl transferases or cause the molecule to be more accessible to glycosylation. The production of asymmetric antibodies can be modified by the physical status (soluble or particulate) of the antigen used as immunogen by the number and frequency of stimulation, and by physiological factors such as the ones secreted by the placenta and by lymphocytes that express progesterone receptors in response to hormone. An increase of these antibodies can be beneficial or harmful to the host, depending on the situation in which they act and the character of self or non-self of the antigens recognized. Editors note—Many of the ideas proposed in this article are very speculative, but it was thought appropriate to publish it in order to stimulate further discussion of the subject. It is an interesting role for Fab glycosylation that is proposed by Professor Margni. The ideas discussed are not necessarily those held by the Editorial Board or the reviewers, who felt that the evidence for many of the deductions made was very limited. It was also emphasized by the reviewers that the author's case would be substantially improved if more corroborative evidence was available from other groups. The Editors would welcome any comments on the subject for publication in future issues of the journal.  相似文献   
8.
During the aparasitaemic period following chemotherapy of all three strains of T. brucei infections in mice, successful transmission as shown by subsequent parasitaemia, was regularly achieved following the inoculation of homogenates of brain tissue into recipient mice. Transmission with blood obtained at the same time was consistently negative and in the case of T. brucei TREU 667, homogenates of other organs were non-infective. The implications of this central nervous system involvement are discussed with particular reference to its use as a model for relapsing infections after therapy in man.  相似文献   
9.
Young chickens inoculated with multiple low doses of mixed oocysts of Eimeria acervulina, E. brunetti, and E. maxima had a high level of resistance to reinfection with a mixed challenge dose on Day 28, Day 84, or Day 140. Immunity was enhanced when the number of immunizing doses was increased from three to four. Resistance was also high in birds maintained on a proprietary mixture of amprolium, ethopabate, and sulphaquinoxaline (Pancoxin-Merck, Sharp and Dohme Ltd.) during immunization, although immunity to E. acervulina was lower in these birds. Oocyst production was lower in birds given mixed infections as compared with that of birds given pure infections with similar doses of oocysts. Competition between species did not inhibit the development of immunity in birds given low doses of mixed oocysts.  相似文献   
10.
杨亚敏  李东明 《菌物学报》2020,39(8):1451-1475
镰刀菌主要为植物致病菌,但也可引起严重人类感染。镰刀菌病临床表现形式多样,本文主要综述相关的皮肤感染,分为局限性皮肤感染及播散性感染,诊断多较困难。由于该属真菌对抗真菌药物存在天然耐药,播散性镰刀菌病死亡率可达80%-90%。本文对Medline和中文文献数据库中的相关文献进行了系统查阅和分析,综合归纳了镰刀菌所致皮肤感染的致病种、地域分布、危险因子、临床表现形式、药物敏感性及其诊疗方案等,该综述对全面了解镰刀菌病的特征及对临床医师对本病的诊断具有重要的意义。  相似文献   
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