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BACKGROUND: In most settings, generalized anxiety disorder (GAD) is highly comorbid with major depressive disorder (MDD). This raises uncertainty about the clinical relevance of GAD as a distinct diagnostic entity. The demonstration of functional impairment attached to GAD, independent of that attributable to MDD, would support the importance of GAD as a separate diagnostic category. METHODS: The Ontario Health Survey Mental Health Supplement, a survey of more than 8000 residents aged 15-64 of the Canadian province of Ontario, used the University of Michigan Composite International Interview Schedule (also used in the US National Comorbidity Survey) to assign DSM-III-R diagnoses. Several indicators of disability and quality of life were included. Our analytic strategy was to compare these indices in persons with and without GAD, stratified by MDD comorbidity, and adjusting for the effects of relevant sociodemographic factors (e.g., social class, age, gender) and dysthymia. Odds ratios (ORs) are reported; SUDAAN was used to adjust for the sampling framework. RESULTS: GAD was highly comorbid with MDD on both a lifetime and past-year basis. Both past-year and lifetime MDD and GAD were associated with an increased likelihood of low overall perceived well-being. Both lifetime MDD and GAD were associated with dissatisfaction in one's main activity and with family relationships. LIMITATIONS: Other comorbid Axis I or II conditions might be confounders with impairment; a lower rate of GAD than in some prior surveys bears consideration. CONCLUSIONS: These observations confirm that GAD is associated with an increased likelihood of poor global well-being and life satisfaction, beyond that associated with MDD. Given the chronicity of GAD relative to the more often episodic course of MDD, the long-term functional benefits of treating GAD may be substantial.  相似文献   
84.
Agrobacteria are associated more commonly with plant than with human disease. The isolation of Agrobacterium radiobacter from blood cultures of an immunocompromised child with a transcutaneous catheter prompted a review of human infections caused by Agrobacterium species. Only 12 reports describing 19 cases of Agrobacterium infections in humans have appeared in the literature. Sixteen of the patients (84%) were equipped with implantable or transcutaneous medical devices at the time of infection, and 14 of the 19 (80%) patients could be considered immunocompromised because of underlying disease processes. Unlike those in previous reports, however, this patient was infected with a novel mucoid phenotype of A. radiobacter. Because of the significant relationship between infection and biomedical implants, we evaluated the adhesion of this mucoid strain and a nonmucoid strain of A. radiobacter to plastic by using two in vitro assays. No adhesion or biofilm formation was detected for either strain, but nonetheless it is clear from this review that the isolation of Agrobacterium spp. from patients with indwelling medical appliances should not be dismissed as an environmental contaminant.  相似文献   
85.
The humoral immune responses to Trypanosoma brucei infection were examined in N'dama and in Zebu, two breeds of cattle recognized for their differing susceptibility to trypanosomiasis. Regardless of the clinical course, animals of both breeds produced antibodies to nonsurface trypanosome antigen(s) detectable by both immunodiffusion and immune fluorescence. As a new approach to assessment of the humoral response to trypanosome infection, protein antigens responded to were isolated by immune precipitation, and their molecular weights were determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This allowed the detection of differences in the immune response which correlated with the clinical course of the disease. All cattle of both breeds which exhibited a capacity to control the disease recognized at least one of three specific antigens: protein of 110,000, 150,000, and 300,000 daltons. The N'dama, which proved less susceptible to the disease, generally responded to more of the three identified trypanosome protein antigens than did the Zebu. Animals which died of trypanosomiasis failed to produce detectable antibodies to any of the three specific proteins, although they sometimes exhibited antibodies to another trypanosome antigen.  相似文献   
86.
Fluorescent in situ hybridisation (FISH) is a powerful tool for the evaluation of chromosomal alterations in formalin fixed paraffin wax embedded sections of colorectal cancer. However, initial experiments using a two-step detection system for digoxigenin labelled chromosome specific centromeric probes resulted in a complete lack of hybridisation signal from a number of colorectal tumour sections. This was due to high levels of background autofluorescence observed in this tissue, which masked any relatively weak hybridisations present. To overcome this problem, a biotinylated tyramide mediated amplification system was incorporated into the FISH detection protocol. This involves the use of horseradish peroxidase to activate the biotinylated tyramide, resulting in the deposition of a large number of biotin molecules at the site of bound peroxidase, which corresponds directly to the location of hybridised probe. Final detection was by means of a streptavidin-FITC conjugate. Using this technique, a panel of 11 colorectal tumour samples studied to date have shown strong, specific hybridisation signals to the nucleus of tumour cells. Amplification of FISH signals by biotinylated tyramide has the potential to improve weak hybridisation signals in cells from numerous sources, using a variety of probe types, including single copy gene probes as well as centromere specific probes.  相似文献   
87.
1. The lateral part of the pericentral cortex of both hemispheres in three awake monkeys was explored with intracortical microstimulation (ICMS) using short trains (T/S; 200-microseconds pulses at 333 Hz for 35 ms, less than or equal to microA) and long trains (C/S; 200-microseconds pulses at 50 Hz for 3 s, less than or equal to 60 microA). In both hemispheres of one of these monkeys, the responsiveness of single cortical neurons to stimulation of the orofacial region was tested at the same intracortical sites where ICMS was applied. 2. Movements were evoked from four physiologically defined cortical regions: the primary face motor cortex (MI), the primary face somatosensory cortex (SI), the principal part of the cortical masticatory area (CMAp) which was located in the precentral gyrus lateral to MI, and a deep part of the cortical masticatory area (CMAd) which was located in the inferior face of the frontal operculum. 3. Two types of cortically induced movements were observed: a single twitch movement and EMG activity of the orofacial muscles that was evoked by T/S at a short latency (10-45 ms) and rhythmical jaw movements (RJMs) which were only evoked by C/S. 4. RJMs were evoked at C/S frequencies ranging from 20 to 300 Hz. At movement threshold, the frequency of the cortically induced RJMs varied from 0.7 to 1.5 Hz and usually increased with the increase of C/S intensity up to 2 times movement threshold. The vertical amplitude of RJMs was also stimulus dependent, and at movement threshold it ranged from 3 to 9 mm. 5. The movement patterns of the cortically induced RJMs remained constant during the course of C/S but could be differentiated in the frontal plane into ipsilateral- (RJMi), vertical-(RJMv), and contralateral- (RJMc) directed movements. These three different patterns of RJMs were associated with different patterns of masticatory muscle activity. 6. Each cortical region contained many sites from which RJMs could be induced (so-called RJM sites). The RJMi sites were more numerous than RJMc sites in all regions except SI and were located anterolateral or lateral to the RJMc sites in each region; the RJMv sites were scattered throughout each cortical region. 7. In MI, C/S elicited RJMs from 94 intracortical sites from which short-latency twitch movements could also be evoked by T/S.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
88.
Rhesus monkeys learned a series of conditional visuomotor associations involving two-dimensional "objects" that instructed one of three responses: tapping a touch screen, steady contact with the screen for a brief period, or steady contact for a longer period. Relative to controls, fornix-transected monkeys were impaired in the acquisition of new associations and in the retention of preoperatively learned ones. These findings challenge the view that the hippocampal system participates in associative learning only when spatial information is relevant to either the stimulus or the response.  相似文献   
89.
Although the detection of fungemia has been improved by the use of vented or biphasic blood culture bottles, the best recovery and earliest detection have been reported in the Isolator lysis-centrifugation system. It was recently demonstrated that improved detection of both bacteria and fungi was accomplished by mechanically agitating blood culture bottles for the first 24 h of incubation. In this study the detection of fungemia by use of the Isolator system was compared with that of an agitated biphasic system. A total of 182 fungi were isolated from blood specimens inoculated into both culture systems. No difference in the overall recovery of fungi or individual species of yeasts was observed between the two systems. However, all seven isolates of Histoplasma capsulatum were recovered in the Isolator system only. The time required to detect fungemia with each of the two systems was also compared. No statistically significant difference was observed. From the data collected during this 18-month study, it can be concluded that the overall recovery and time of detection of yeasts are equivalent in the lysis-centrifugation system and the agitated biphasic blood culture system. The lysis-centrifugation system is still superior for the detection of filamentous fungi such as H. capsulatum.  相似文献   
90.
A previous study has suggested that Fusobacterium nucleatum FN-2 contains a galactose-binding protein (lectin) on the cell surface (P. A. Murray, V. Matarese, C. I. Hoover, and J. R. Winkler, FEMS Microbiol. Lett. 40:123-127, 1987). In the present study, the molecular specificity and size of this lectin were investigated by several techniques. Whole-cell affinity chromatography with asialofetuin covalently coupled to Sepharose 6MB demonstrated that 81% of 3H-labeled F. nucleatum were specifically eluted by 0.5 M galactose. Specific binding was calcium dependent and did not occur in the presence of calcium chelators. Binding was inhibited by preincubation with galactose. Agglutination of human parotid saliva by F. nucleatum was also inhibited by galactose and its structural analogs. Inhibition by lactose was 2 times that of galactose, inhibition by p-aminophenyl galactosides was 4 times that of galactose, and inhibition by asialoglycopeptides was 100 times that of galactose. Similar inhibition results were obtained for hemagglutination of neuraminidase-treated erythrocytes. These findings suggest that the binding specificity of F. nucleatum FN-2 is more complex than simply the recognition of the monosaccharide galactose. This is consistent with the concept that lectins considered identical in terms of monosaccharide specificity can recognize fine differences in more complex structures. To identify the specific bacterial component(s) involved in galactose recognition, proteins of F. nucleatum FN-2 were separated on a 4 to 11% gradient sodium dodecyl sulfate slab gel, transferred to nitrocellulose paper to renature bacterial binding sites, and then incubated with 125I-labeled asialofetuin. Autoradiographs of the nitrocellulose revealed a band at a range of Mr 300,000 to 330,000 which was not present when the blots were preincubated with galactose. These data support the concept that F. nucleatum FN-2 possesses a lectin that recognizes galactose and galactose-containing substrates.  相似文献   
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