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991.
This paper proposes the hypothesis that cells which express fetal antigen activate a variety of suppressor mechanisms and thus induce a state of immunological tolerance. Clinical and experimental evidence is cited which supports the hypothesis and indicates that foreign antigens, expressed in association with fetal antigen, are actively tolerated. Thus the fetus, which bears foreign histocompatibility antigens and neoplastic tumours which re-express fetal antigens, fail to evoke appropriate immunological rejection responses, but rather induce a state of active tolerance.  相似文献   
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Music perception is important to cochlear implant patients, but little effort has been devoted to improving signal processing for music. In this preliminary investigation, we probed the importance of number of channels and stimulus rate. We asked eight users of the Clarion cochlear implant to rate music quality on a scale from 0 to 100 on three different types of music (country and western, pop and classical). Patients rated eight- and one-channel processors running at a fast and slow rate. The stimulus rate was 200 pps for the slow rate. For the eight-channel condition, the fast rate varied from 394 to 765 pps. For the one-channel condition, the fast rate varied from 2601 to 4335 pps. Results indicated that the eight-channel condition was uniformly rated higher than the one-channel condition. However, the results for stimulus rate were less clear. No patients assigned higher ratings with the slow rate, but only three subjects assigned higher ratings with the fast rate. We conclude that music perception can be influenced and probably improved by signal processing. The number of channels, or perhaps spectral representation, is critical for music appreciation by cochlear implant recipients.  相似文献   
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IntroductionObesity is a major health problem that is associated with many physiological and mental disorders, such as diabetes, stroke, and depression. Gut microbiota has been affirmed to interact with various organs, including the brain. Intestinal microbiota and their metabolites might target the brain directly via vagal stimulation or indirectly through immune‐neuroendocrine mechanisms, and they can regulate metabolism, adiposity, homoeostasis and energy balance, and central appetite and food reward signaling, which together have crucial roles in obesity. Studies support the concept of bidirectional signaling within the gut–brain axis (GBA) in the pathophysiology of obesity, mediated by metabolic, endocrine, neural, and immune system mechanisms.Materials and methodsScopus, PubMed, Google Scholar, and Web of Science databases were searched to find relevant studies.ResultsThe gut–brain axis (GBA), a bidirectional connection between the gut microbiota and brain, influences physiological function and behavior through three different pathways. Neural pathway mainly consists of the enteric nervous system (ENS) and vagus nerve. Endocrine pathway, however, affects the neuroendocrine system of the brain, particularly the hypothalamus–pituitary–adrenal (HPA) axis and immunological pathway. Several alterations in the gut microbiome can lead to obesity, by modulating metabolic pathways and eating behaviors of the host through GBA. Therefore, novel therapies targeting the gut microbiome, i.e., fecal microbiota transplantation and supplementation with probiotics and prebiotics, can be a potential treatment for obesity.ConclusionThis study corroborates the effect of gut microbiome on physiological function and body weight. The results show that the gut microbiota is becoming a target for new antiobesity therapies.  相似文献   
996.
Percutaneous transluminal angioplasty of subclavian arteries   总被引:1,自引:0,他引:1  
The clinical records and procedural details of 30 subclavian angioplasty procedures attempted in 27 patients were reviewed. Long-term follow-up was obtained through referring physician records and direct telephone contact with the patients. Eight patients presented with neurologic symptoms only, six had arm claudication only, nine had both neurologic and arm symptoms, three underwent dilations to provide graft inflow, and one was asymptomatic. Procedural complications included a stroke in the contralateral carotid distribution, occurring during follow-up arch aortography, and an embolus in the fifth digit of the left hand, which was of no clinical significance. Long-term success did not correlate well with degree of stenosis, lesion length, or postangioplasty appearance. The patients with arm and neurologic symptoms who were followed up for 3 years experienced immediate relief and remained symptom free or improved, except for the patient who suffered the stroke and one patient with labyrinthitis.  相似文献   
997.
Pityriasis Versicolor and Pityrosporum ovale   总被引:2,自引:0,他引:2  
Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) have been performed on skin material of patients with pityriasis versicolor who were orally treated with itraconazole. Before as well as after therapy, variously sized spherical structures were observed on the surface of the keratinocytes with SEM. TEM examination revealed Pityrosporum ovale, predominantly in its mycelial phase, inside keratinocytes. The spherules as observed by SEM appeared to be amorphous, lipid-like droplets originating from the inside of the keratinocytes. The cytoplasm of the keratinocytes was at least partly occupied by the same amorphous material. It is therefore suggested that P. ovale penetrates the keratinocyte where degradation of the normal keratinous content to amorphous material takes place. This newly formed lipidic substrate may be an essential nutritive factor. The lipidified state of the stratum corneum persisted for at least 3 weeks after eradication of the fungus by itraconazole. It is speculated that the presence of large quantities of this lipid-like material might be the cause of hypopigmentation because it may constitute an ultraviolet light block.  相似文献   
998.
We present the case of a 59-year-old woman who had large ulcerations on her right leg that were diagnosed initially as pyoderma gangrenosum and treated with three immunosuppressive agents (cyclosporin, prednisone and azathioprine) for 6 months. Results of a biopsy at 6 months showed numerous cigar-shaped bodies consistent with Sporothrix schenckii; identification was confirmed by tissue culture. A retrospective review was performed for all cases diagnosed as sporotrichosis from tissue culture or biopsy specimens at the Mayo Clinic. Nineteen cases were identified. The present case was the only one in which fungal organisms were visible on histological examination. The present case emphasizes the importance of making a definitive histological diagnosis in unusual ulcer cases or in suspected cases of pyoderma gangrenosum before the initiation of immunosuppressive therapy. The large number of cigar-shaped bodies in the tissue is a rare finding in sporothrix infection and has been reported in only two cases previously.  相似文献   
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