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971.
BACKGROUND: This study evaluated the clinical and sociodemographic features associated with various degrees of concurrent comorbidity in adult outpatients with nonpsychotic major depressive disorder (MDD). METHODS: Outpatients enrolled in the STAR*D trial completed the Psychiatric Diagnostic Screening Questionnaire (PDSQ). An a priori 90% specificity threshold was set for PDSQ responses to ascertain the presence of 11 different concurrent DSM-IV Axis I disorders. RESULTS: Of 1376 outpatients, 38.2% had no concurrent comorbidities, while 25.6% suffered one, 16.1% suffered two, and 20.2% suffered three or more comorbid conditions. Altogether, 29.3% met threshold for social anxiety disorder, 20.8% for generalized anxiety disorder, 18.8% for posttraumatic stress disorder, 12.4% for bulimia, 11.9% for alcohol abuse/dependence, 13.4% for obsessive-compulsive disorder, 11.1% for panic disorder, 9.4% for agoraphobia, 7.3% for drug abuse/dependence, 3.7% for hypochondriasis, and 2.2% for somatoform disorder. Those with more concurrent Axis I conditions had earlier ages at first onset of MDD, longer histories of MDD, greater depressive symptom severity, more general medical comorbidity (even though they were younger than those with fewer comorbid conditions), poorer physical and mental function, health perceptions, and life satisfaction; and were more likely to be seen in primary care settings. LIMITATIONS: Participants had to meet entry criteria for STAR*D. Ascertainment of comorbid conditions was not based on a structured interview. CONCLUSIONS: Concurrent Axis I conditions (most often anxiety disorders) are very common with MDD. Greater numbers of concurrent comorbid conditions were associated with increased severity, morbidity, and chronicity of their MDD.  相似文献   
972.
973.
Pneumococcal adherence to alveolar epithelial cells and nasopharyngeal epithelial cells has been well characterized. However, the interaction of Streptococcus pneumoniae with bronchial epithelial cells has not been studied. We have now shown that pneumococci bind specifically to a human bronchial epithelial cell line (BEAS-2B cells). Pneumococci adhered to BEAS-2B cells in a time- and dose-dependent manner. These results suggest that the bronchial epithelium may serve as an additional site of attachment for pneumococci and demonstrate the utility of the BEAS-2B cell line for studying mechanisms of pneumococcal infection.  相似文献   
974.
Two vaccine, two respiratory (infectious bovine rhinotracheitis [IBR]), and two genital (infectious pustular vulvovaginitis [IPV]) strains of infectious bovine rhinotracheitis virus were compared by neutralization kinetics using late 19S antibody (AB). The two vaccine strains were indistinguishable from one another, but were neutralized far more rapidly than the other four strains when either anti-IBR or anti-IPV 19S AB was used. The two IPV strains were indistinguishable from one another, but were neutralized significantly more rapidly than the two IBR strains when anti-IBR 19S AB was used. The 2 IBR strains were neutralized at a similar rate with the latter globulin preparation. Almost identical results were obtained with anti-IPV 19S AB, except that one IPV strain was neutralized at a rate similar to the IBR strains. However, when early and late rabbit 7S AB were used, IBR strains could not be distinguished from IPV strains by neutralization kinetics. Preliminary experiments indicated that both early and late 19S rabbit antibodies neutralized the homologous strain more rapidly than the heterologous strain, but the difference was more noticeable with late 19S AB. It was also determined that neutralization of IBR-IPV virus by specific early and late 19S rabbit AB and early 7S rabbit AB was markedly enhanced by guinea pig complement. Neutralization of this virus by late 7S AB, however, was only slightly enhanced by complement. These results suggest that vaccine strains of IBR-IPV virus may be distinguished by neutralization kinetics with late 19S rabbit AB, and that genital and respiratory strains may possibly also be distinguishable with some 19S AB preparations.  相似文献   
975.
Ethanol tolerance, a decrease in drug responsiveness with repeated administrations, is an important diagnostic criterion for alcoholism. Rapid tolerance develops within 8-24 hours of an initial ethanol exposure and shares many similarities with chronic tolerance. The genetic contribution to rapid tolerance to ethanol-induced ataxia was estimated using a panel of inbred strains of mice. Strains differed significantly in the degree of rapid tolerance development, which had a broad-sense heritability estimate of 0.11. Artificial selection was carried out to develop lines of mice that would show High (HRT) and Low (LRT) levels of Rapid Tolerance. Starting with HS/Npt mice, derived from a systematic cross of eight inbred strains, a significant response to selection was seen in replicate 1 by the third selection generation. No difference was found in replicate 2. Heritability estimates after the fourth generation were 0.25 for HRT-1 mice and 0.06 for LRT-1 mice. HRT-1 and LRT-1 mice also differed significantly in chronic tolerance development to four doses of ethanol. These studies provide evidence for a genetic contribution to rapid tolerance and support a genetic link between rapid and chronic tolerance to ethanol's ataxic effects.  相似文献   
976.
We showed that Borrelia burgdorferi-vaccinated interferon gamma-deficient (IFN-gamma(0)) mice challenged with the Lyme spirochete developed a prominent chronic severe destructive osteoarthropathy. The immune response underlying the development of the severe destructive arthritis involves interleukin-17 (IL-17). Treatment of vaccinated IFN-gamma(0) mice challenged with B. burgdorferi with anti-IL-17 antibody delayed the onset of swelling of the hind paws but, more importantly, inhibited the development of arthritis. Histopathologic examination confirmed that treatment with anti-IL-17 antibody prevented the destructive arthropathy seen in vaccinated and challenged IFN-gamma(0) mice. Similar preventive results were obtained when vaccinated and challenged IFN-gamma(0) mice were treated with anti-IL-17 receptor antibody or sequentially with anti-IL-17 antibody followed by anti-IL-17 receptor antibody. By contrast, treatment of vaccinated and challenged IFN-gamma(0) mice with recombinant IL-17 (rIL-17) did not alter the development and progression of arthritis found in vaccinated and challenged IFN-gamma(0) mice without treatment with rIL-17. Therapeutic intervention may be a realistic approach to prevent arthritis, especially if IL-17 is involved in the perpetuation of chronic or intermittent arthritis.  相似文献   
977.
Neoplasms of histiocytes and dendritic cells are rare, and their phenotypic and biological definition is incomplete. Seeking to identify antigens detectable in paraffin-embedded sections that might allow a more complete, rational immunophenotypic classification of histiocytic/dendritic cell neoplasms, the International Lymphoma Study Group (ILSG) stained 61 tumours of suspected histiocytic/dendritic cell type with a panel of 15 antibodies including those reactive with histiocytes (CD68, lysozyme (LYS)), Langerhans cells (CD1a), follicular dendritic cells (FDC: CD21, CD35) and S100 protein. This analysis revealed that 57 cases (93%) fit into four major immunophenotypic groups (one histiocytic and three dendritic cell types) utilizing six markers: CD68, LYS, CD1a, S100, CD21, and CD35. The four (7%) unclassified cases were further classifiable into the above four groups using additional morphological and ultrastructural features. The four groups then included: (i) histiocytic sarcoma (n=18) with the following phenotype: CD68 (100%), LYS (94%), CD1a (0%), S100 (33%), CD21/35 (0%). The median age was 46 years. Presentation was predominantly extranodal (72%) with high mortality (58% dead of disease (DOD)). Three had systemic involvement consistent with 'malignant histiocytosis'; (ii) Langerhans cell tumour (LCT) (n=26) which expressed: CD68 (96%), LYS (42%), CD1a (100%), S100 (100%), CD21/35 (0%). There were two morphological variants: cytologically typical (n=17) designated LCT; and cytologically malignant (n=9) designated Langerhans cell sarcoma (LCS). The LCS were often not easily recognized morphologically as LC-derived, but were diagnosed based on CD1a staining. LCT and LCS differed in median age (33 versus 41 years), male:female ratio (3.7:1 versus 1:2), and death rate (31% versus 50% DOD). Four LCT patients had systemic involvement typical of Letterer-Siwe disease; (iii) follicular dendritic cell tumour/sarcoma (FDCT) (n=13) which expressed: CD68 (54%), LYS (8%), CD1a (0%), S100 (16%), FDC markers CD21/35 (100%), EMA (40%). These patients were adults (median age 65 years) with predominantly localized nodal disease (75%) and low mortality (9% DOD); (iv) interdigitating dendritic cell tumour/sarcoma (IDCT) (n=4) which expressed: CD68 (50%), LYS (25%), CD1a (0%), S100 (100%), CD21/35 (0%). The patients were adults (median 71 years) with localized nodal disease (75%) without mortality (0% DOD). In conclusion, definitive immunophenotypic classification of histiocytic and accessory cell neoplasms into four categories was possible in 93% of the cases using six antigens detected in paraffin-embedded sections. Exceptional cases (7%) were resolvable when added morphological and ultrastructural features were considered. We propose a classification combining immunophenotype and morphology with five categories, including Langerhans cell sarcoma. This simplified scheme is practical for everyday diagnostic use and should provide a framework for additional investigation of these unusual neoplasms.  相似文献   
978.
Content and contextual memory for remote public figures and events was assessed with a modified version of the Presidents Test in patients with Alzheimer's disease (AD) or Parkinson's disease (PD). Contributions of executive functioning, semantic memory, and explicit anterograde memory to remote memory abilities were also examined. The AD group had temporally extensive deficits in content and contextual remote memory not accountable for by dementia severity. The PD group did not differ from the control group in remote memory, despite anterograde memory impairment. These results support the position that different component processes characterize remote memory, various mnemonic and nonmnemonic cognitive processes contribute to remote memory performance, and anterograde and remote memory processes are dissociable and differentially disrupted by neurodegenerative disease.  相似文献   
979.
Primitive Neuroectodermal Tumors of the Central Nervous System   总被引:2,自引:0,他引:2  
Controversial issues relating to the pathobiology and classification of central nervous system primitive neuroectodermal tumors (PNETs) have plagued neuropathologists for more than 70 years. Hypotheses advanced in the mid-1920's have remained as fixed concepts in contemporary literature, largely consequent to repetitious support by a small number of neuropathologists despite a growing body of information discrediting these ideas from neuroembryologists, oncologists, neuroscien-tists and pathologists.
Attention has largely focused upon PNETs arising in the cerebellum (commonly known as medul-loblastomas [MBs]), because about 80% of central nervous system (CNS) PNETs originate in this site. It has been asserted that the 20% which do not are biologically different, although most individuals agree that the histological features of PNETs that occur in different sites throughout the CNS are indistinguishable from those growing in the cerebellum.
The historical aspects of this controversy are examined in the face of evidence that there is, in fact, a unique class of CNS tumors which should appropriately be regarded as primitive neuroectodermal in nature. Specifically, a number of different approaches to the problem have yielded data supporting this hypothesis. These approaches include the identification of patterns of expression among a variety of cellular antigens (demonstrated by the use of immunopathological techniques), molecular analyses of cell lines derived from these tumors, experimental production of PNETs and molecular genetic analyses.
Differences of opinion among surgeons, oncologists and radiotherapists are typically resolved by conducting cooperative studies of patients with these tumors who are diagnosed and treated at multiple centers.  相似文献   
980.
On two occasions, six well-trained, male competitive triathletes performed, in random order, two experimental trials consisting of either a timed ride to exhaustion on a cycle ergometer or a run to exhaustion on a motor-driven treadmill at 80% of their respective peak cycling and peak running oxygen (VO2max) uptakes. At the start of exercise, subjects drank 250 ml of a 15 g·100 ml–1 w/v [U-14C]glucose solution and, thereafter, 150 ml of the same solution every 15 min. Despite identical metabolic rates [VO2 3.51 (0.06) vs 3.51 (0.10) 1·min–1; values are mean (SEM) for the cycling and running trials, respectively], exercise times to exhaustion were significantly longer during cycling than running [96 (14) vs 63 (11) min; P < 0.05]. The superior cycling than running endurance was not associated with any differences in either the rate of blood glucose oxidation [3.8 (0.1) vs 3.9 (0.4) mmol· min–1], or the rate of ingested glucose oxidation [2.0 (0.1) vs 1.7 (0.2) mmol· min–1] at the last common time point (40 min) before exhaustion, despite higher blood glucose concentrations at exhaustion during running than cycling [7.0 (0.9) vs 5.8 (0.5) mmol·1–1; P < 0.05]. However, the final rate of total carbohydrate (CHO) oxidation was significantly greater during cycling than running [24.0 (0.8) vs 21.7 (1.4) mmol C6·min–1; P < 0.01]. At exhaustion, the estimated contribution to energy production from muscle glycogen had declined to similar extents in both cycling and running [68 (3) vs 65 (5)%]. These differences between the rates of total CHO oxidation and blood glucose oxidation suggest that the direct and/or indirect (via lactate) oxidation of muscle glycogen was greater in cycling than running.  相似文献   
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