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11.
Breath tests have gained increasing interest in recent years mainly driven by the unmet clinical need to monitor airway diseases and to obtain information on unravelled aspects of respiratory disorders. A prototype of such measurement reaching clinical significance besides its use as a research tool is the measurement of exhaled nitric oxide (NO). It took hardly more than a decade after the discovery that exhaled breath contains NO for this measurement to be approved for clinical practice to monitor anti-inflammatory treatment in asthma. Recent studies demonstrate that using exhaled NO measurement to guide anti-inflammatory treatment in asthma may help clinical decision making. A similarly small molecule present in exhaled breath is carbon monoxide, which is not only a biomarker of cigarette smoking but has also been suggested to reflect ongoing oxidative stress/antioxidant defense. The scope of this review is the exciting field of exhaled monoxides. Since several other biomarkers have also been studied in the exhaled breath this review will provide a brief introduction to them.  相似文献   
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The opportunistic pathogens Rhizomucor pusillus and Rhizomucor miehei may be agents of frequently fatal mycotic diseases. In the present study, the susceptibilities of 27 clinical and environmental isolates of R. miehei and R. pusillus to lovastatin under different culturing conditions were investigated. Most of the R. miehei strains grew at lovastatin concentrations as high as 64 to 128 microg/ml. In contrast, the inhibitory effect of lovastatin on all of the R. pusillus strains was evident at lovastatin concentrations as low as 1 to 2 microg/ml. A simple and reliable method for species-level differentiation, based on the significantly higher sensitivity of R. pusillus to lovastatin than that of R. miehei, was elaborated. According this, on malt extract agar containing 6 mug of lovastatin/ml, R. pusillus is not able to produce colonies, while R. miehei will form compact colonies.  相似文献   
13.
Cells from the CD4+ murine T hybridoma line IP-12-7 enter the apoptotic suicide program via the Fas ligand (FasL)/Fas-mediated pathway upon TCR stimulation. This stimulus regulates the sensitization of the Fas death pathway and the cell surface appearance of preformed FasL. The apoptosis is dependent on new mRNA and protein synthesis and involves up-regulation of nur77.Two groups of nuclear receptors for retinoic acids (RA) have been identified: retinoic acid receptors (RAR) and retinoid X receptors. IP-12-7 cells express RARalpha and RARgamma. Here we show that,in the IP-12-7 T cells, RA also induced the expression and DNA binding of nur77, and the cell surface appearance of FasL. The induction was mediated via RARgamma. Despite the induced expression of cell surface FasL, only two structurally related RARgamma-selective compounds, CD437 and CD2325, initiated apoptosis in these cells. The lack of apoptosis induction by natural RA was related to the inability of RARgamma to sensitize the Fas death-pathway. Cell surface FasL, however, was able to induce cell death in Fas-bearing target cells. Natural RA also induced the expression of FasL in phytohemagglutinin-activated peripheral murine T cells. It is proposed that therapeutically administered RA might induce apoptosis in Fas-sensitive cells via induction of FasL expression in activated Tcells.  相似文献   
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The Agrobacterium -mediated transformation was adapted to Backusella lamprospora, a zygomycete fungus closely related to Mucor. The transforming plasmid contained the hygromycin B resistance (hph) and the green fluorescent protein (gfp) genes under the control of the regulator regions of the Mucor circinelloides gpd1 gene. The presence of the hph and gfp genes in the transformants was detected by PCR. The introduced genes could also be amplified directly from the spores of the transformants. The transformation efficiency was investigated by fluorescence microscopy of the transformed spores. A gradual decrease in the hygromycin B resistance was observed during several cultivation cycles: the growth of the transformants on the selection medium became slower, and the detection of the introduced gene became more difficult.  相似文献   
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Molnár I 《Autoimmunity》2007,40(1):31-37
Th1 and Th2-like cytokines are involved in the pathogenesis of Graves' disease. The shift in balance in IL-12/IL-5 cytokines was applied in judging the immunological events in 74 patients with Graves' disease (50 had ophthalmopathy) during methimazole therapy and in 15 controls. The serum levels of IL-12 and IL-5 were measured with enzyme-linked immunosorbent assay in all Graves' patients. Twelve cases for IL-5 and 20 cases for IL-12 were positive. In Graves' patients only those without ophthalmopathy had higher levels of IL-12 when compared to controls (192.66 +/- 29.19 vs. 85.09 +/- 8.95 pg/ml, P < 0.04). After 2 months of methimazole therapy in Graves' patients without ophthalmopathy an increase in the ratio of IL-12 to IL-5 was also observed as compared to those with eye symptoms (91.78 +/- 34.14 vs. 20.72 +/- 6.36, P < 0.015). Age-related difference in the serum level of IL-5 could be demonstrated between Graves' patients without and those with ophthalmopathy aged < or = 35 years (4.89 +/- 0.57 vs. 50.14 +/- 20.2 pg/ml, P < 0.002). No association was found among the serum levels of IL-5 or IL-12, thyroid hormones and TSH receptor antibodies. The results demonstrated a difference in the balance shift of IL-12/IL-5 between Graves' patients with and without ophthalmopathy. The increased ratio of IL-12 to IL-5 after methimazole therapy could be explained by the elevation of serum IL-12 due to methimazole therapy and the age-related decrease of serum IL-5.  相似文献   
18.
There is strong evidence that commissural interneurons, neurons with axons that extend to the contralateral side of the spinal cord, play an important role in the coordination of left/right alternation during locomotion. In this study we investigated the projections of commissural interneurons to motor neurons and other commissural interneurons on the other side of the spinal cord in neonatal rats. To establish whether there are direct contacts between axons of commissural interneurons and motor neurons, we carried out two series of experiments. In the first experiment we injected biotinylated dextran amine (BDA) into the lateral motor column to retrogradely label commissural interneurons that may have direct projections to motor neurons. Stained neurons were recovered in the ventromedial areas of the contralateral gray matter in substantial numbers. In the second experiment BDA was injected into the ventromedial gray matter on one side of the lumbar spinal cord, whereas motor neurons were simultaneously labeled on the opposite side by applying biocytin onto the ventral roots. BDA injections into the ventromedial gray matter labeled a strong axon bundle that arose from the site of injection, crossed the midline in the ventral commissure, and extensively arborized in the contralateral ventral gray matter. Many of these axons made close appositions with dendrites and somata of motor neurons and also with commissural interneurons retrogradely labeled with BDA. The results suggest that commissural interneurons may establish monosynaptic contacts with motor neurons on the opposite side of the spinal cord. Our findings also indicate that direct reciprocal connections between commissural interneurons on the two sides of the spinal cord may also exist.  相似文献   
19.
Cleidocranial dysplasia (CCD) is an uncommon, generalized skeletal disorder characterized by delayed ossification of the skull, aplastic or hypoplastic clavicles, and serious, complex dental abnormalities. There are many difficulties in the early diagnosis of CCD because a majority of the craniofacial abnormalities becomes obvious only during adolescence. In the present case, a hypoplastic midface, a relative prognathia of the mandible, and close approximation of the shoulders in the anterior plane were the conspicuous extraoral findings. Prolonged exfoliation of the primary dentition, unerupted supernumerary teeth, and the irregularly and partially erupted secondary dentition produced occlusional anomalies. The presence of the second permanent molars together with the primary dentition and wide spacing in the lower incisor area were typical dental signs. Gradual extraction of the supernumerary teeth and over-retained primary teeth was the first step of oral surgery. This was followed by a surgical exposure of the unerupted teeth by thinning of the cortical bone. Orthodontic treatment was aimed at parallel growth of the jaws. Removable appliances were used to expand the narrow maxillary and mandibular arches, and a Delaire mask compensated for the lack of sagittal growth of the upper jaw. Temporary functional rehabilitation was solved by partial denture. When the jaws have been fully developed, implant insertions and bridges are the therapeutic measures. The reported case and the literature data support the importance of the early diagnosis and interdisciplinary treatment of CCD.  相似文献   
20.
Serious, prolonged intrafamilial childhood sexual abuse is considered to be the main etiological factor in about half of the patients with borderline personality disorder in the USA. Special features of childhood interpersonal trauma leading to the development of borderline personality disorder are the seriousness of the trauma and the fact that it is sexual in nature. Serious intrafamilial childhood abuse can lead not only to the classic post-traumatic stress syndrome, but can influence all aspects of personality development, including the distortion of the sense of identity, self-regulation, and the patterns of interpersonal relations. Viewed from the perspective of the trauma concept, the entire range of adult borderline symptoms are considered as being the consequences of severe complex traumatic experiences. Other clinicians regard such an abuse as a marker of the severity of familial dysfunction and emphasize the role of other pathogenic factors, such as biparental neglect and biological vulnerability of the pre-borderline child.  相似文献   
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