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21.
Imaging with technetium-99m sestamibi offers a non-invasive approach to detect the presence of functional P-glycoprotein (Pgp), one of the major causes of multidrug resistance, in human malignancies. A clinical role for Pgp has been suggested in the subpopulation of primary neuroblastoma without amplification of the proto-oncogene MYCN. We wanted to evaluate the usefulness of 99mTc-sestamibi scintigraphy in the screening of neural crest tumours for the presence of Pgp. In ten children suffering from MYCN-negative neuroblastoma, ganglioneuroblastoma or ganglioneuroma, 99mTc-sestamibi imaging was performed at initial diagnosis. All patients underwent planar imaging 20-30 min and 3.5-4 h after intravenous injection of 740 MBq/1.73 m2 99mTc-sestamibi. Tumour to normal tissue ratios, as well as washout rates, were determined and compared with in vitro flow cytometric analysis of Pgp expression and function. Pgp expression was analysed flow cytometrically with the monoclonal antibodies 4E3 and MRK16, and Pgp function was evaluated by means of rhodamine 123 uptake and efflux either in the absence or in the presence of the Pgp inhibitor verapamil. In nine of ten patients, we found that the intratumoral 99mTc-sestamibi activity was comparable to the background activity, which might be suggestive of Pgp presence. This was confirmed flow cytometrically in all but one patient. 99mTc-sestamibi enhancement was seen in the primary tumour and the bone marrow metastases of one of the ten patients, and this result was concordant with a negative Pgp status. The findings presented suggest that 99mTc-sestamibi imaging results might correlate with the presence of functional Pgp in neural crest tumours without MYCN amplification.  相似文献   
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The improvement of quality of life is one of the major goals in the treatment of patients after renal transplantation. While immunosuppressive therapy is present in almost all of these patients, little is known about the effects of newer immunosuppressive agents. We therefore investigated the impact of tacrolimus on life quality. From November 1997 to January 1998, a questionnaire was handed out which focussed on physical and mental problems as well as sexual capacity and the attitudes towards graft, donor and transplant related side effects. 50 kidney graft recipients treated with tacrolimus were matched to 50 patients with a cyclosporine-based immunosuppression (= controls). Values are given as mean +/- standard deviation. Tacrolimus treated patients had a mean creatinine of 1.8 +/- 0.8 mg/dl, as compared to 1.6 +/- 0.7 mg/dl in controls. The overall status of health was assessed to be good in 82% of the tacrolimus group (controls: 80%). 38% were working full-time (controls: 20%). Only 14% of patients described their physical condition as poor (16% in controls). Sexual function was good in 66% (controls: 74%) and poor in 10% (controls: 12%). Mental function was assessed to be good in 92% (controls: 82%). The majority of patients felt comfortable with their physical, sexual and mental capabilities. This was independent from the immunosuppressive regimen.  相似文献   
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BACKGROUND: Renal hemodynamics and immune responses differ between males and females. Thus, sex hormones and genetically determined gender differences may determine the process of chronic rejection to some extent. METHODS: Female (F) or male (M) F344 kidneys were orthotopically transplanted into ovariectomized female Lewis recipients and were treated for 16 weeks with either estradiol, testosterone, or vehicle. RESULTS: Testosterone treatment resulted in increased urinary protein excretion independently of the donor gender, as well as extended glomerular sclerosis, interstitial fibrosis, and severe vascular lesions. Additionally, mononuclear cell infiltration was most pronounced in these animals, in parallel to an increased expression of intercellular adhesion molecule-1 (ICAM-1), fibronectin, laminin, and transforming growth factor-beta (TGF-beta) in the grafts. Estradiol treatment resulted in an improved graft function, reduced glomerular sclerosis, and a diminished cellular infiltration, in parallel to a reduced ICAM-1, fibronectin, laminin, and TGF-beta expression. In animals treated with vehicle, the gender of the donor influenced the outcome. Grafts of male origin had good graft function and histology, whereas grafts from female donors developed severe proteinuria and glomerular, interstitial, and vascular damage. CONCLUSIONS: These results suggest that a protective effect of estradiol on the progression of chronic rejection exists that is independent of donor gender. Additionally, a male kidney may benefit from the absence of testosterone, whereas the function of a female kidney deteriorates in the absence of estradiol.  相似文献   
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The aetiology of malignant melanoma is not wholly explained by exposure to sunshine. The present of arsenic in the soil has been suggested as a possible causative factor. Geographical clustering of malignant melanoma cases in the South Western Region is demonstrated for males and this clustering is associated with the distribution of arsenic in the soil. No evidence of geographical clustering is however found for females. This suggests possible sex-specific differences in the aetiology of malignant melanoma and indicates the need for further study of the association with arsenic.

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25.
The concept of major depression   总被引:1,自引:0,他引:1  
Six operational definitions of the concept of major depression were submitted to empirical evaluation in 600 psychiatric inpatients. Special attention was given to the comparison of major depression in DSM-III-R and ICD-10. The data base created by a polydiagnostic interview revealed relevant classificatory differences between the six definitions under study. Sources of different diagnostic base rates were: inclusion or omission of anhedonia as an obligatory mood criterion; minimal number of syndrome criteria required for the syndrome diagnosis; different width and reference points of time criteria; exclusion rules for co-existing schizophrenic symptoms and for previous nonaffective and manic episodes. The empirically evaluated overlap between pairs of diagnostic definitions was less than excellent in most of the diagnostic definitions under study; only the DSM-III and DSM-III-R definitions agreed with each other to a highly comparable degree. The relatively good agreement of the 1989 draft definition of ICD-10 for major depression ("mild depression") with the other five operational definitions (kappa = 0.69) led us to expect that this definition should receive sufficient international acceptance.  相似文献   
26.
Serum cystatin C, a cysteine proteinase inhibitor, has been proposed as a marker of glomerular filtration rate (GFR). Serum cystatin C, serum creatinine and creatinine clearance were measured in 226 patients with various nephropathies, covering the entire range of renal function, to evaluate the efficacy of cystatin C as a screening test to detect reduced creatinine clearance in comparison to creatinine. Subgroups of 53 patients with glomerular and 26 patients with tubular impairment were compared to assess whether cystatin C performed differently in either glomerular or tubular impairment. Cystatin C detected reduced creatinine clearance with higher sensitivity (97 vs. 83%), and higher negative predictive value (96 vs. 87%) compared to creatinine. In parallel, 95% sensitivity of cystatin C as derived from receiver-operating characteristic plot was significantly higher (p < 0.05). In the subgroups with glomerular or tubular impairment, cystatin C and creatinine did not significantly differ with regard to efficacy. Serum cystatin C is as efficacious as serum creatinine to detect reduced GFR as measured by creatinine clearance. The efficacy of cystatin C as a screening test may even be superior compared to creatinine. In addition, the efficacy of cystatin C is independent of either glomerular or tubular impairment.  相似文献   
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BackgroundIn response to the COVID-19 pandemic, countries are introducing digital passports that allow citizens to return to normal activities if they were previously infected with (immunity passport) or vaccinated against (vaccination passport) SARS-CoV-2. To be effective, policy decision-makers must know whether these passports will be widely accepted by the public and under what conditions. This study focuses attention on immunity passports, as these may prove useful in countries both with and without an existing COVID-19 vaccination program; however, our general findings also extend to vaccination passports.ObjectiveWe aimed to assess attitudes toward the introduction of immunity passports in six countries, and determine what social, personal, and contextual factors predicted their support.MethodsWe collected 13,678 participants through online representative sampling across six countries—Australia, Japan, Taiwan, Germany, Spain, and the United Kingdom—during April to May of the 2020 COVID-19 pandemic, and assessed attitudes and support for the introduction of immunity passports.ResultsImmunity passport support was moderate to low, being the highest in Germany (775/1507 participants, 51.43%) and the United Kingdom (759/1484, 51.15%); followed by Taiwan (2841/5989, 47.44%), Australia (963/2086, 46.16%), and Spain (693/1491, 46.48%); and was the lowest in Japan (241/1081, 22.94%). Bayesian generalized linear mixed effects modeling was used to assess predictive factors for immunity passport support across countries. International results showed neoliberal worldviews (odds ratio [OR] 1.17, 95% CI 1.13-1.22), personal concern (OR 1.07, 95% CI 1.00-1.16), perceived virus severity (OR 1.07, 95% CI 1.01-1.14), the fairness of immunity passports (OR 2.51, 95% CI 2.36-2.66), liking immunity passports (OR 2.77, 95% CI 2.61-2.94), and a willingness to become infected to gain an immunity passport (OR 1.6, 95% CI 1.51-1.68) were all predictive factors of immunity passport support. By contrast, gender (woman; OR 0.9, 95% CI 0.82-0.98), immunity passport concern (OR 0.61, 95% CI 0.57-0.65), and risk of harm to society (OR 0.71, 95% CI 0.67-0.76) predicted a decrease in support for immunity passports. Minor differences in predictive factors were found between countries and results were modeled separately to provide national accounts of these data.ConclusionsOur research suggests that support for immunity passports is predicted by the personal benefits and societal risks they confer. These findings generalized across six countries and may also prove informative for the introduction of vaccination passports, helping policymakers to introduce effective COVID-19 passport policies in these six countries and around the world.  相似文献   
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