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121.
OBJECTIVE: This study examines factors affecting the frequency of physician consultations by individuals with functional gastrointestinal disorders (FGD) in a group of subjects with functional dyspepsia or irritable bowel syndrome. Systematic selection of persons who were already seeing a physician for one of these problems was avoided by conducting an epidemiological field study rather than a clinical study. METHODS: A representative sample of the German population (N=2201) completed a questionnaire that included, in addition to the criterion (number of physician visits in the past 12 months), items aimed at identifying the target group and questions about physical symptoms, illness behavior, living situation, personality features, and sociodemographic status (a total of 31 predictors). RESULTS: Individuals with functional gastrointestinal disorders who consulted a physician for their gastrointestinal disorders and those who did not differed significantly, especially on psychological measures. The differences between these individuals and the general population were greater for the consulters than for the nonconsulters. Multiple regression analyses yielded nine predictors that explained 40.2% of the variance of the criterion. The best predictors of frequency of physician consultations were the duration of periods with symptoms and psychological factors, such as the severity of depression and the patients' views on the cause of their illness. CONCLUSIONS: The psychopathology seen in people with functional gastrointestinal disorders is of two types: one is a characteristic of the illness itself and the other leads the individual to consult a physician. When gastroenterologists see patients with such disorders, they can assume that they may be dealing with a self-selected group of individuals with psychological stress. Psychological assessment would, therefore, be useful to determine whether a given individual with FGD might benefit from psychotherapy.  相似文献   
122.
Mechanisms of suppression by suppressor T cells   总被引:52,自引:0,他引:52  
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123.
A Western blot to detect anti-HSP70 autoantibodies has been reported to be of diagnostic value for immune-mediated hearing loss patients. While setting up this Western blot in our lab, we detected two main problems. First, some patients were positive for antibodies to a 70-kDa protein when tested against a whole cell lysate, but negative if the antigen used was purified HSP70. Second, if high amounts of purified HSP70 were loaded on the gel, both patients and healthy controls were positive. We have developed and optimized an ELISA as an alternative to the Western blot. This assay is more appropriate to identify positive and negative individuals because it is semi-quantitative. The ELISA is also more sensitive, requiring very low concentrations of the antigen and thus minimizing false positives. Finally, we demonstrated that immune-mediated hearing loss patients recognize mainly the native form of HSP70, a fact that potentially leads to false negatives when a denaturing Western blot assay is used for diagnosis. To test the diagnostic value of the ELISA, we performed a blind test with 70 hearing loss patients, as well as 30 healthy controls. A sensitivity of 84% and a specificity of 93% were obtained, superior to what has been reported so far for the Western blot.  相似文献   
124.
Fiber tracking allows the in vivo reconstruction of human brain white matter fiber trajectories based on magnetic resonance diffusion tensor imaging (MR-DTI), but its application in the clinical routine is still in its infancy. In this study, we present a new software for fiber tracking, developed on top of a general-purpose DICOM (digital imaging and communications in medicine) framework, which can be easily integrated into existing picture archiving and communication system (PACS) of radiological institutions. Images combining anatomical information and the localization of different fiber tract trajectories can be encoded and exported in DICOM and Analyze formats, which are valuable resources in the clinical applications of this method. Fiber tracking was implemented based on existing line propagation algorithms, but it includes a heuristic for fiber crossings in the case of disk-shaped diffusion tensors. We successfully performed fiber tracking on MR-DTI data sets from 26 patients with different types of brain lesions affecting the corticospinal tracts. In all cases, the trajectories of the central spinal tract (pyramidal tract) were reconstructed and could be applied at the planning phase of the surgery as well as in intraoperative neuronavigation.  相似文献   
125.
In 1942, Jaffe and Lichtenstein introduced the term aneurysmal bone cyst (ABC). Primary ABC is characterized by the presence of spongy or multi-cameral cystic tissue filled with blood. The process is benign, but it is locally destructive and has a high propensity for recurrence. In this paper, we present the third case of multiple metachronous primary ABCs as a rare variant of ABC. We describe the 10-year history of a 12-year-old boy with metachronous multiple primary ABCs at five different sites (right proximal humerus, right ulna, bilateral distal radius and right lateral clavicle). Furthermore, our patient suffered from vascular malformations, such as aortic isthmus stenosis, hypoplastic thoraco-abdominal aorta and bilateral renal artery stenosis. To date, in contrast to solitary ABC, the multiple lesions have been found more frequently in male individuals. Using interphase cytogenetics, we analyzed three of five of the patients ABCs and one of these was also analyzed by GTG-banding. No chromosomal abnormalities were found. Significantly, we excluded the missense mutation of codon 201 in guanine nucleotide-binding protein 1 gene consistently found in McCune-Albright syndrome (MAS) and in non-MAS cases of polyostotic fibrous dysplasia of bone with or without secondary ABC.  相似文献   
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128.
Widespread antibiotic resistance has been recognized in Escherichia coli isolates from human, animal and environmental sources. Although prevalence rates for resistant E. coli strains are significantly distinct for various populations and environments, the impact of resistance to antimicrobial drugs is ubiquitous. This article provides information about the epidemiology, mechanisms and molecular principles of resistance, shows consequences for the antiinfective treatment of selected infections and describes measures to control the spread of antibiotic-resistant E. coli.  相似文献   
129.
Zusammenfassung Von 11 Carcinoidpatienten mit vermehrter Serotonin-Synthese hatten 10 Patienten Diarrhöe, 9 Patienten nachweisbare Lebermetastasen und 7 Patienten zeigten eine Kardiopathie. Sieben Patienten hatten spontane Flushanfälle. Bei diesen Patienten konnte ein Flush auch durch intravenöse Injektion von Aminen oder Bradykinin hervorgerufen werden. Bei 3 Patienten ohne Spontanflush in der Anamnese konnte ein Flush durch Provokation nicht ausgelöst werden. Der durch Amine provozierte Flush wurde von allen Patienten als dem Spontanflush gleich empfunden. Nur die Hälfte der Patienten empfanden den Bradykinin induzierten Flush gleich dem Spontanflush. Regitinbehandlung verhindert den durch Amine provozierten Flush und verminderte die Anzahl der spontanen Flushanfälle.Die Behandlung mit p-Chlorphenylalanin (PCP) in einer Dosierung bis zu 3 g täglich resultierte bei allen Patienten in einer Verminderung der 5-Hydroxyindolessigsäure-Ausscheidung und der Diarrhöe. Bei 3 Patienten mit vermehrter 5-Hydroxytryptophan-Ausscheidung wurde diese durch PCP vermindert, was darauf hindeutet, daß die Tryptophanhydroxylase durch PCP gehemmt wird. Die PCP-Behandlung, die bis zu einer Dauer von 120 Tagen durchgeführt wurde, zeigte bei den Patienten keine Nebenwirkungen.Mit Unterstützung der Schwedischen Cancer-Gesellschaft.  相似文献   
130.
Since substance P (SP)-like immunoreactivity has been demonstrated in vagal sensory fibres of bronchopulmonary origin, it was considered of interest to (1) characterize the pattern of responses to SP injected into the pulmonary as well as the systemic arterial system, and (2) assess the types of vagal afferents that are affected by SP. Experiments were performed on 15 pentobarbital-anaesthetized, spontaneously breathing rabbits. Efferent phrenic nerve activity was monitored as an index of central respiratory neural output. Intra-atrial injections of SP into the pulmonary circulation (100 ng kg-1) increased the respiratory rate, and peak integrated phrenic amplitude by 47 +/- 8 and 40 +/- 4%, respectively, above the controls. In addition, SP elicited augmented breaths (ABs) within 2-3 s in 67% of the trials. In contrast to right atrial injections, no ABs and no significant changes in respiratory rate were observed in response to intra-aortic injections of SP (100 ng kg-1). Tidal phrenic activity rise after aortic injections of SP was significantly less as compared with right atrial administrations of SP. Since both routes of administration decreased the arterial blood pressure to the same extent, these respiratory responses were not likely secondary to cardiovascular changes. After administration of an SP antagonist (D-Arg-D-Trp7,9, Leu11, SP), respiratory responses to SP were significantly attenuated. Also, the rate of occurrence of ABs elicited by releasing the tracheal occlusions was reduced (control 95 vs. 14% SP antagonist). Bilateral vagotomy abolished the tachypnoeic response and reduced the magnitude of the phrenic nerve increments caused by right atrial injection of SP.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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