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排序方式: 共有1774条查询结果,搜索用时 15 毫秒
1.
Andreas Karatsaidis Olav Schreurs Kristen Helgeland Tony Axéll Karl Schenck 《Journal of oral pathology & medicine》2003,32(5):275-281
BACKGROUND: Common clinical forms of oral lichen planus (OLP) and oral lichenoid reactions (OLR) are erythematous (ERY) or reticular (RET). The purpose of this study was to find histopathological changes that differ between these forms. METHODS: Epithelial thickness, epithelial proliferation rate, apoptosis, and HLA-DR expression were compared among 10 reticular and 12 erythematous lesions, and 11 normal oral mucosa samples (NOM). RESULTS: The epithelium in ERY was thinner than in NOM, whereas RET showed values between ERY and NOM. Cell proliferation increased significantly in ERY as compared with RET and NOM, with no difference between RET and NOM. Relative numbers of epithelial cell nuclei displaying visible chromatin condensation were reduced in ERY form. CONCLUSIONS: The markedly increased cell proliferation in ERY supports the notion that this form displays a higher disease activity as compared to RET. It can therefore be important to study each disease form separately. 相似文献
2.
Erling Gjengedal Gisle Uppheim Håvard Bjerkholt Øystein Høvik Olav Reikerås 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2007,17(3):279-284
We report the outcome of a femoral stem designed for press-fit insertion and cemented with a thin mantle. During the years 1986–1992 we performed 346 primary total hip replacements in 305 patients. Their mean age at the time of the surgery was 75 (range, 52–91 years). During the follow-up, 206 patients had died (227 hips) and 3 were lost. This left us with 96 patients (116 hips), who were followed for a mean of 13 years (range, 11–18 years). Stem survivorship according to Kaplan–Meier analysis indicated a total survival of 0.982 (confidence intervals, 0.952–1). The mechanical survival rate was 0.985 (confidence intervals, 0.955–1) at 17 years with one patient at risk. Fifty-nine (70%) of the surviving patients were very satisfied with the operated hip, 22 (26%) were satisfied, 2 (2.5%) were content, and 1 (1.5%) was dissatisfied. Then, the press-fit stem allowing minimal cement has a 17-year survival rate of 0.98. 相似文献
3.
Posterior dislocations of the sternoclavicular joint are uncommon, but are potentially quite serious. Radiologic diagnosis and management are frequently difficult. The specialized projections available are not widely known, and the role of plain films is poorly understood. The incidence, pathomechanics, and clinical manifestations of such dislocations are presented and the radiologic diagnosis is discussed. 相似文献
4.
Gunnar Franzn Olav G. Klausen Ronald T. Grenko John Carstensen Bo Nordenskjld 《The Laryngoscope》1991,101(6):669-673
A retrospective study was performed on 20 patients with adenoid cystic carcinomas of major salivary glands to see if DNA. patterns correlated with their prognoses. Fourteen tumors were found to be DNA. diploid; 6 were DNA aneuploid. Histologically, all DNA-aneu-ploid tumors had solid components, compared with only 5 of the DNA-diploid tumors. All of the DNA-aneuploid tumors recurred, in contrast to only 2 of the DNA-diploid tumors; the difference was highly significant (P<0.001). All of the patients with no recurrences had DNA-diploid tumors. In our study, DNA measurements of adenoid cystic carcinomas gave statistically significant information about prognosis and correlated to histological grading. We propose that evaluation of DNA content may be performed before planning the treatment of adenoid cystic carcinomas. 相似文献
5.
Richard Werner Karsten Alfke Tobias Schaeffter Arya Nabavi H Maximilian Mehdorn Olav Jansen 《Magnetic resonance in medicine》2004,52(6):1443-1447
A new method for the selective spin labeling of left- or right-sided supplying arteries of the brain without the need for additional RF coils is demonstrated. A clinical 1.5 T scanner was used. The spatial selectivity of the labeling process is based on the limited coverage of the excitation field of a standard send/receive head coil together with an oblique positioning of the labeling plane. A computer simulation was used to optimize key labeling parameters under the condition of laminar flow. The validity of the computer model results was confirmed by MRI measurements with a flow model. For human studies, a double-inversion continuous arterial spin labeling (CASL) sequence was modified to allow for arbitrary positioning of the labeling plane. The obtained perfusion-weighted images showed a clear delineation of the perfusion territories of the selected arteries in the anterior circulation of the brain and good gray/white matter contrast. 相似文献
6.
I. Sandanger T. Moum G. Ingebrigtsen O. S. Dalgard T. Sørensen D. Bruusgaard 《Social psychiatry and psychiatric epidemiology》1998,33(7):345-354
The definition of case is a core issue in psychiatric epidemiology. Psychiatric symptom screening scales have been extensively
used in population studies for many decades. Structured diagnostic interviews have become available during recent years to
give exact diagnoses through carefully undertaken procedures. The aim of this article was to assess how well the Hopkins Symptom
Checklist-25 (HSCL-25) predicted cases by the Composite International Diagnostic Interview (CIDI), and find the optimal cut-offs
on the HSCL-25 for each diagnosis and gender. Characteristics of concordant and discordant cases were explored. In a Norwegian
two-stage survey mental health problems were measured by the HSCL-25 and the CIDI. Only 46% of the present CIDI diagnoses
were predicted by the HSCL-25. Comorbidity between CIDI diagnoses was found more than four times as often in the concordant
cases (cases agreed upon by both instruments) than in the discordant CIDI cases. Concordant cases had more depression and
panic/generalized anxiety disorders. Neither the anxiety nor the depression subscales improved the prediction of anxiety or
depression. The receiver operating characteristic (ROC) curves confirmed that the HSCL-25 gave best information about depression.
Except for phobia it predicted best for men. Optimal HSCL-25 cut-off was 1.67 for men and 1.75 for women. Of the discordant
HSCL-25 cases, one -third reported no symptoms in the CIDI, one-third reported symptoms in the CIDI anxiety module, and the
rest had symptoms spread across the modules. With the exception of depression, the HSCL-25 was insufficient to select individuals
for further investigation of diagnosis. The two instruments to a large extent identified different cases. Either the HSCL-25
is a very imperfect indicator of the chosen CIDI diagnoses, or the dimensions of mental illness measured by each of the instruments
are different and clearly only partly overlapping.
Accepted: 11 November 1997 相似文献
7.
T G Ksiazek P E Rollin P B Jahrling E Johnson D W Dalgard C J Peters 《Journal of clinical microbiology》1992,30(4):947-950
A sandwich enzyme immunosorbent assay (EIA) using a mixture of mouse monoclonal antibodies for antigen capture and polyclonal hyperimmune rabbit anti-Ebola virus serum for antigen detection was developed and evaluated on the tissues of monkeys naturally or experimentally infected with strains of Ebola viruses. When compared with virus isolation, the antigen detection EIA was both sensitive and specific: 44 of 45 (97.7%) liver homogenates and 38 of 41 (92.7%) spleen homogenates that were culture positive and tested by both techniques were positive for viral antigen, while 85 of 87 (97.7%) culture-negative liver homogenates and 66 of 66 culture-negative spleen homogenates were found to be antigen negative. The assay, initially developed to detect antigens of prototype African strains of Ebola virus, reliably detected related strains of Ebola virus found during two recent outbreaks of Ebola virus infection among imported, quarantined Macaca fascicularis monkeys in the United States. The assay allows economical and rapid testing of large numbers of tissue specimens. Antigen was found in homogenates of spleen and liver and in serum. 相似文献
8.
The influence of social class, strain and social support on symptoms of anxiety and depression in mothers of toddlers 总被引:3,自引:0,他引:3
Background: The aim of the study was to identify risk and protective factors for anxiety and depression among mothers of toddlers. Methods: A population-based sample of 921 Norwegian mothers with 18-month-old children completed a questionnaire designed to examine
the impact of socioeconomic and demographic factors, somatic health problems, negative life events, chronic strain and social
support on symptoms of anxiety and depression (HSCL-25). Results: There was a moderate aversive effect of negative life events and chronic strain and a moderate protective effect of social
support on the symptom level, but no interaction effects were found between the risk and protective factors. Behaviour problems
among the children clearly seemed to affect the mothers' symptom level. The symptom level varied with background factors like
the mothers' education, employment status and age even after controlling for the effect of strain and social support. The
largest effect of the background factors seemed to be indirect, however, mediated through their effect on the risk and protective
factors. Conclusions: Although problems with the children's behaviour and child care arrangements were observed to have a strong impact on the
mothers' symptom level, the frequencies of such problems appeared to be less dependent on socioeconomic conditions than did
other types of strain.
Accepted: 21 July 1998 相似文献
9.
Life stress, social support and psychological distress in late adolescence: a longitudinal study 总被引:7,自引:0,他引:7
Questionnaire data from 211 adolescents and follow-up data recorded 18 months later were employed to test main effects and
stress-buffering effects of negative life events, on-going stressors and social support from family and friends on mental
health. Negative life events, change from baseline level of on-going adversities and social support all contributed significantly
to subsequent symptom scores, although negative life events only reached borderline significance among boys. There was evidence
in favour of the buffer hypothesis for boys: negative life events had a significantly stronger effect when social support
from peers was low, and long-lasting adversities had a significantly stronger effect when social support from parents was
low. Both these two-way interaction effects among boys were significantly different from the corresponding trends among girls.
Since the scores on both the independent and dependent variables are based on subjective self-reports, the results may have
been affected by various types of response bias. The probabilities of such bias effects are discussed.
Accepted: 13 March 1998 相似文献
10.
Sandanger I Nygård JF Ingebrigtsen G Sørensen T Dalgard OS 《Social psychiatry and psychiatric epidemiology》1999,34(11):570-579
Background: Increased demands for psychiatric services and increased rates of sickness absence for depression have raised the question
of the occurrence of psychiatric disorders in Norway, and whether there is in fact a rising incidence rate. Methods: Between 1989–1991, 2015 and 617 persons participated in a two-phase population study. Phase I comprised screening by the
Hopkins Symptom Check List 25 items (HSCL-25), and phase II a diagnostic interview by the Composite International Diagnostic
Interview (CIDI), including report of date (year) of the first occurrence of any symptoms, and any consequent diagnosis: Results: A symptom score of 1.75 or more was found in 19.8% of the women and 9.3% of the men by the HSCL-25. Depression, anxiety
or somatoform disorder by CIDI was found in 21.5% of the women and 11.5% of the men. The incidence rate increased significantly
from 3.3 to 12.8 per 1000 person years from 1930 to 1991. The incidence rate in the year before the interview was 42.6 per
1000 person years. Age of onset became lower. More women became ill, but the illness seemed to last longer in men. A major
problem in comparing results between studies is the different concepts and operationalisations of psychiatric illness, and
the varying time periods given for estimates. Conclusion: The findings provide evidence of psychiatric illness being a rising and major health problem, but the role of recall bias
must be further investigated.
Accepted: 19 August 1999 相似文献