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排序方式: 共有993条查询结果,搜索用时 15 毫秒
981.
982.
Loss of idealism or realistic optimism? A cross‐sectional analysis of dental hygiene students’ and registered dental hygienists’ professional identity perceptions 下载免费PDF全文
983.
984.
985.
Comparison of cytopathic changes in oral hairy leukoplakia with in situ hybridization for EBV DNA 总被引:1,自引:0,他引:1
JS Greenspan YG de Souza JA Regezi TE Daniels D Greenspan LA MacPhail JF Hilton 《Oral diseases》1998,4(2):95-99
OBJECTIVE: It has been observed that the cytopathic changes in hairy leukoplakia (HL) correlate with ultra-structural evidence of intra-keratinocyte herpes-type viral particles. In situ hybridization is considered to be the definitive confirmation of Epstein-Barr virus (EBV)-induced HL. This study evaluated the consistency of histopathological findings, which many believe to be diagnostic, with in situ hybridization for EBV-DNA in 60 patients with lesions clinically suggestive of HL.
MATERIALS AND METHODS: Hematoxylin and eosin (H&E)-stained sections were reviewed independently by three oral pathologists who did not know the hybridization results. The presence in keratinocytes of nuclear inclusions and/or homogenization, believed to be specific for EBV in these lesions, was used as an indicator for infection. Cytoplasmic changes were evaluated separately.
RESULTS: With in situ hybridization, 48 cases were positive and 12 were negative. When the two methods were compared, pathologist concurrence ranged from 83% to 92%. False negatives ranged from 6% to 19%, and false positives ranged from 8% to 25%. Cytoplasmic ballooning, homogenization, and perinuclear clearing were evident in all cases of hybridization-confirmed HL; however, these changes were also noted in 75% (9/12) of the cases with negative hybridization results. Most confirmed HL cases exhibited both nuclear homogenization and inclusions, although the former was more consistently seen.
CONCLUSION: Cytoplasmic changes did not agree well with EBV-DNA hybridization results, whereas nuclear changes demonstrated good, but not complete, agreement. In appropriate clinical settings, the finding of nuclear inclusions and/or homogenization may be of diagnostic value. However, because the potential for false positives and negatives is high, H&E cytopathology should not be used as a substitute for in situ hybridization in the definitive diagnosis of oral hairy leukoplakia. 相似文献
MATERIALS AND METHODS: Hematoxylin and eosin (H&E)-stained sections were reviewed independently by three oral pathologists who did not know the hybridization results. The presence in keratinocytes of nuclear inclusions and/or homogenization, believed to be specific for EBV in these lesions, was used as an indicator for infection. Cytoplasmic changes were evaluated separately.
RESULTS: With in situ hybridization, 48 cases were positive and 12 were negative. When the two methods were compared, pathologist concurrence ranged from 83% to 92%. False negatives ranged from 6% to 19%, and false positives ranged from 8% to 25%. Cytoplasmic ballooning, homogenization, and perinuclear clearing were evident in all cases of hybridization-confirmed HL; however, these changes were also noted in 75% (9/12) of the cases with negative hybridization results. Most confirmed HL cases exhibited both nuclear homogenization and inclusions, although the former was more consistently seen.
CONCLUSION: Cytoplasmic changes did not agree well with EBV-DNA hybridization results, whereas nuclear changes demonstrated good, but not complete, agreement. In appropriate clinical settings, the finding of nuclear inclusions and/or homogenization may be of diagnostic value. However, because the potential for false positives and negatives is high, H&E cytopathology should not be used as a substitute for in situ hybridization in the definitive diagnosis of oral hairy leukoplakia. 相似文献
986.
A Chanson† N Cardinault† E Rock† JF Martin† P Souteyrand‡ M D'Incan‡ P Brachet† 《Journal of the European Academy of Dermatology and Venereology》2008,22(1):94-100
Background In the last two decades, there has been an increasing use of isotretinoin (13‐cis‐retinoic acid or 13‐CRA) for treatment of severe, and recently mild and moderate, acne in Westernized populations. Recent human and animal studies emphasized alterations caused by 13‐CRA administration on folate‐dependent, one‐carbon metabolism. Folate deficiency and subsequent hyperhomocysteinemia increase the risk of degenerative diseases. Objectives We determine whether a short‐term supplementation with 13‐CRA alters folate status and homocysteinemia in young and elderly healthy human subjects. Methods Twenty young and 20 elderly (age mean, 26.1 and 65.4 years, respectively) healthy male volunteers were supplemented with ~0.5 mg/kg/day of 13‐CRA for 28 days. Fasting plasma concentrations of 13‐CRA, 5‐methyltetrahydrofolate (5‐mTHF) as the main circulating form of folate, and homocysteine (Hcy), as well as haematologic parameters and biochemical markers of liver and renal function, were measured at baseline and at the end of supplementation. Statistical analyses were carried out using two‐way anova and standard tests. Results In both groups, isotretinoin supplementation caused a dramatic increase in the circulating concentration of 13‐CRA and its derivatives. It also led to significant increases in serum triglyceride (P < 0.0001) and creatinine (P = 0.002) concentrations and γ‐glutamyltranspeptidase activity (P = 0.0001) and decrease in serum level of urea (P = 0.027). However, the latter four parameters remained within normal ranges. These changes were accompanied by a 17.7% and 13.5% decrease in the plasma level of 5‐mTHF (P = 0.001) in the young and elderly volunteers, respectively. Supplementation with 13‐CRA did not cause significant variations in their plasma Hcy concentration. However, the latter parameter seemed to respond differently in each group of age (P = 0.046). Conclusions Our data indicate that a 28‐day supplementation with isotretinoin alters the plasma folate in young and old healthy individuals. This stresses the necessity of studying the long‐term effects of retinoid therapy on folate status and homocysteinemia in acne patients, given that alteration in the latter parameters is known to increase the risk of degenerative diseases. 相似文献
987.
Aurima Stankuniene Mindaugas Stankunas Joaquim JF Soares Mark Avery M Gabriella Melchiorre Francisco Torres-Gonzalez Raimondas Radziunas Algirdas Baranauskas Jutta Lindert 《Daru : journal of Faculty of Pharmacy, Tehran University of Medical Sciences》2012,20(1):78
Background
The use of medicines by elderly people is a growing area of concern in social pharmacy. A significant proportion of older people do not follow the recommendations from physicians and refrain from buying prescribed medications. The aim of this study is to evaluate associations between self-rated health, somatic complaints and refraining from buying prescribed medications by elderly people.Findings
Data was collected in a cross-sectional study in 2009. We received 624 completed questionnaires (response rate – 48.9%) from persons aged 60–84 years living in Kaunas (Lithuania). Somatic complaints were measured with the 24 item version of the Giessen Complaint List (GBB-24). Logistic regression (Enter model) was used for evaluation of the associations between refraining from buying medications and somatic complaints. These associations were measured using odds ratio (OR) and calculating the 95% confidence interval (CI).The mean scores in total for the GBB scale and sub-scales (exhaustion, gastrointestinal and cardiovascular) were lowest among respondents who did not refrain from buying prescribed medications (means for GBB-24 scale: 21.04 vs. 24.82; p=0.001). Logistic regression suggests that somatic complaints were associated with a increased risk of refraining from buying prescribed medications (OR=1.35, 95% CI=1.15-1.60).Conclusions
Somatic complaints were significantly associated with the decision to refrain from buying prescribed medications. 相似文献988.
989.
MJ Huijbers J Spijker AR Donders DJ van Schaik P van Oppen HG Ruhé MB Blom WA Nolen J Ormel GJ van der Wilt W Kuyken P Spinhoven AE Speckens 《BMC psychiatry》2012,12(1):125-11
Background
Depression is a common psychiatric disorder characterized by a high rate of relapse and recurrence. The most commonly used strategy to prevent relapse/recurrence is maintenance treatment with antidepressant medication (mADM). Recently, it has been shown that Mindfulness-Based Cognitive Therapy (MBCT) is at least as effective as mADM in reducing the relapse/recurrence risk. However, it is not yet known whether combination treatment of MBCT and mADM is more effective than either of these treatments alone. Given the fact that most patients have a preference for either mADM or for MBCT, the aim of the present study is to answer the following questions. First, what is the effectiveness of MBCT in addition to mADM? Second, how large is the risk of relapse/recurrence in patients withdrawing from mADM after participating in MBCT, compared to those who continue to use mADM after MBCT?Methods/design
Two parallel-group, multi-center randomized controlled trials are conducted. Adult patients with a history of depression (3 or more episodes), currently either in full or partial remission and currently treated with mADM (6?months or longer) are recruited. In the first trial, we compare mADM on its own with mADM plus MBCT. In the second trial, we compare MBCT on its own, including tapering of mADM, with mADM plus MBCT. Follow-up assessments are administered at 3-month intervals for 15?months. Primary outcome is relapse/recurrence. Secondary outcomes are time to, duration and severity of relapse/recurrence, quality of life, personality, several process variables, and incremental cost-effectiveness ratio.Discussion
Taking into account patient preferences, this study will provide information about a) the clinical and cost-effectiveness of mADM only compared with mADM plus MBCT, in patients with a preference for mADM, and b) the clinical and cost-effectiveness of withdrawing from mADM after MBCT, compared with mADM plus MBCT, in patients with a preference for MBCT.Trial registration
ClinicalTrials.gov: NCT00928980 相似文献990.
The authors studied the ability of real-time ultrasound aided by color Doppler flow imaging to demonstrate the deep veins of the calf in ten healthy subjects and 49 patients (91 limbs) with suspected deep venous thrombosis. Posterior tibial and peroneal veins demonstrated flow accentuation in 98% (74 of 75) and 96% (72 of 75), respectively, of the limbs without thrombosis and in all 20 normal limbs. Sixteen legs were involved with deep venous thrombosis. Peroneal veins could not be seen in three legs with marked calf swelling due to proximal thrombosis. There were two cases of thrombosis limited to the calf, nine of popliteal thrombosis (seven with contiguous spread of thrombus), and five of thrombosis limited to above the knee (four with sparing of the deep veins of the calf). Visualization of anterior tibial veins, achieved in 65% of all legs, did not correlate with thrombosis. The authors conclude that color Doppler flow imaging can demonstrate patency of posterior tibial and peroneal veins in most patients without deep venous thrombosis and aid in detection of below-the-knee thrombosis. 相似文献