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11.
郭永建 《福建医科大学学报》1994,(1)
采用间接ELISA检测23名肾移植受者血清巨细胞病毒(CMV)抗体,共检出18名(78%)活动性CMV感染,其中10名(44%)为原发性感染。结果证实CMV-IgE和-IgA具有较好的血清学诊断价值,优于CMV-IgM。 相似文献
12.
The retinal pigment epithelium (RPE) plays several important roles in the continual support and renewal of photoreceptor outer segments. In the present study, we have demonstrated that RPE cells contain a low molecular weight protein with a high capacity for zinc binding that is dependent on available sulfhydryl groups. This protein is inducible by a 24 hour incubation of cultured RPE in medium supplemented with zinc, cadmium, or dexamethasone. The induction of this protein is correlated with an increased capacity for zinc-65 uptake into cultured RPE. Analysis with a cDNA probe specific for the human metallothionein II gene corroborated the existence and induction of metallothionein gene products in RPE cells. Based on these properties, we have identified this protein as metallothionein. The induction of metallothionein likely has a critical influence on the zinc economy of the RPE. 相似文献
13.
AIM: Our aim was to determine how the risk associated with presence of low transcutaneous oxygen tension (tcPO2) for subsequent major amputation in patients with skin ulcers or gangrene and peripheral arterial disease, compares with the risks associated with low peripheral pressures and low amplitude of pulse waves. Secondly, we determined whether combination of measurements of oxygen tension with that of the pressures or pulse wave amplitude predicts amputation better than pressure, wave or oxygen tension measurements alone. METHODS: Measurements were carried out to obtain foot tcPO2, ankle and toe pressures, pressure indices, and toe pulse wave amplitude in 75 limbs with skin lesions and arterial disease of 66 patients referred to the vascular laboratory. These variables were related to the risk of a subsequent major amputation during a median time of 4.2 years, using Cox proportional hazards model. RESULTS: Low oxygen tension was associated with increased risk of amputation (relative risks 2.16 and 2.55 for tcPO2 < or = 10 mmHg and < or = 20 mmHg, respectively, P<0.05; relative risk 2.22 for tcPO2 < or = 30 mmHg, P=0.07). The relative risks associated with cutoff values of ankle and toe pressures and pressure indices varied from 2.53 (toe < or = 20 mmHg, P<0.05) to 5.83 (ankle < or = 50 mmHg, P<0.001) and the relative risk associated with low wave amplitude (< or = 4 mm) was 3.41, P<0.01. The cutoff values of tcPO2 became insignificant when included in the models together with each pressure variable or pulse amplitude separately. In contrast, wave amplitude remained significantly associated with increased risk of amputation after controlling for each pressure variable (P<0.05). CONCLUSIONS: TcPO2 < or = 10 mmHg and < or = 20 mmHg are related significantly to increased risk of amputation in patients with skin lesions and arterial disease, but these relative risks are similar in magnitude or smaller than those associated with low cutoff values of pressures, pressure indices or pulse wave amplitude. Low wave amplitude does provide significant information in addition to peripheral pressures with respect to the risk of amputation. On the other hand, low tcPO2 does not provide significant information in addition to peripheral pressures or pulse wave amplitude. 相似文献
14.
CA von Arnim R Spoelgen ID Peltan M Deng S Courchesne M Koker T Matsui H Kowa SF Lichtenthaler MC Irizarry BT Hyman 《The Journal of neuroscience》2006,26(39):9913-9922
The beta-amyloid (Abeta) precursor protein (APP) is cleaved sequentially by beta-site of APP-cleaving enzyme (BACE) and gamma-secretase to release the Abeta peptides that accumulate in plaques in Alzheimer's disease (AD). GGA1, a member of the Golgi-localized gamma-ear-containing ARF-binding (GGA) protein family, interacts with BACE and influences its subcellular distribution. We now report that overexpression of GGA1 in cells increased the APP C-terminal fragment resulting from beta-cleavage but surprisingly reduced Abeta. GGA1 confined APP to the Golgi, in which fluorescence resonance energy transfer analyses suggest that the proteins come into close proximity. GGA1 blunted only APP but not notch intracellular domain release. These results suggest that GGA1 prevented APP beta-cleavage products from becoming substrates for gamma-secretase. Direct binding of GGA1 to BACE was not required for these effects, but the integrity of the GAT (GGA1 and TOM) domain of GGA1 was. GGA1 may act as a specific spatial switch influencing APP trafficking and processing, so that APP-GGA1 interactions may have pathophysiological relevance in AD. 相似文献
15.
Thrombin activity by intrinsic activation of plasma in-vitro accelerates with increasing age of the donor. 总被引:3,自引:0,他引:3
Thrombotic diseases increase in incidence with advancing years and this might be partly due to an increased propensity for fibrin formation in older individuals. Accordingly we decided to investigate whether the time taken to generate 50% thrombin activity in vitro varied with the age of the plasma donor. Coagulation was initiated in defibrinated, diluted plasma by contact activation and thrombin activity measured using the chromogenic substrate, S2238. The rate of thrombin generation was assessed by measuring the time taken to reach 50% maximal activity (T50/s). There was a highly significant negative correlation between T50 and age, T50 declining from 93 s at 19 years to 71 s at 65 years (r = -0.637, p less than 0.0001). A strong negative correlation was demonstrated between T50 and FVII level (r = -0.415, p = 0.0007) and FVIII:C level (r = -0.465, p = 0.0001). Although FVII concentration correlated with age (r = 0.307, p = 0.014) no relationship was seen between age and FVIII:C. These data suggest that coagulation rates in plasma accelerate with age. 相似文献
16.
CA Schroeter† L Kaas† JJ Waterval† PM Bos‡ HAM Neumann§ 《Journal of the European Academy of Dermatology and Venereology》2007,21(9):1170-1174
AIM: The aim of this pilot study was an investigation on photodynamic therapy (PDT) whether it is a good alternative for treating periungual and subungual warts of the hands. STUDY DESIGN: Twenty patients (mean age: 30.5 years) with a total of 40 periungual and subungual warts were treated with PDT. A photosensitizer, 20%delta-aminolevulinic acid was applied on the warts. After a mean incubation time of 4.6 h (SD: 1.2), the warts were irradiated with the VersaLight for 5-30 min (15.2 +/- 4.3 min). RESULTS: After a mean of 4.5 treatments a mean clearance of 100% was achieved in 90% of the patients. One patient (5%) showed a clearance of 50% and another showed no improvement. The subungual or periungual location of the wart had no influence on the number of treatments or end result (P > 0.05). There were two recurrences during the mean follow-up period of 5.9 months (SD: 7.6). Besides mainly pain and hyperpigmentation, most treatments had no side-effects. CONCLUSION: PDT can offer a good alternative for treating periungual warts of the hands. Larger studies are indicated. 相似文献
17.
Verbal Working Memory and Atherosclerosis in Patients with Cardiovascular Disease: An fMRI study 总被引:1,自引:0,他引:1
Andreana P. Haley PhD Lawrence H. Sweet PhD John Gunstad PhD Daniel E. Forman MD Athena Poppas MD Robert H. Paul PhD David F. Tate PhD Ronald A. Cohen PhD 《Journal of neuroimaging》2007,17(3):227-233
BACKGROUND AND PURPOSE: Intimal-medial thickening (IMT) of the carotid wall is an accepted peripheral marker of atherosclerosis. It is associated with increased risk for myocardial infarction and stroke, and lower attention-executive-psychomotor functioning. The purpose of this study was to examine the relationship between IMT and brain activity during a verbal working memory (VWM) task in patients with cardiovascular disease (CVD). METHODS: Thirteen CVD patients underwent functional magnetic resonance imaging (fMRI) during a 2-Back VWM task, and B-mode ultrasound of the carotid arteries. IMT was calculated using an automated algorithm based on a validated edge-detection technique. The relationship between IMT and 2-Back-related brain activity was modeled using partial correlations controlling for age and small vessel disease as measured by white matter signal hyperintensities on MRI (WMH). RESULTS: Higher IMT was associated with lower 2-Back-related signal intensity and in the right middle frontal gyrus, independent of age and WMH. CONCLUSIONS: IMT may be one mechanism contributing to brain dysfunction in CVD. The blood oxygenation level-dependent (BOLD) contrast appears to be highly sensitive to peripheral vascular health as measured by IMT. Future studies should examine the sensitivity and specificity of the BOLD response for predicting cognitive decline in CVD. 相似文献
18.
L E Nicolle L Buffet N Alfieri R Tate 《Infection control and hospital epidemiology》1988,9(12):553-558
In a one-year retrospective review, 138 symptomatic infections were identified in 145 admissions to a rehabilitation unit. One hundred twenty-six (91%) infections were either urinary or skin and soft tissue infections. The daily incidence of infection increased with increasing numbers of infections for infected patients. Patient factors associated with infection included male sex, young age, spinal cord injury, admission for management of decubitus ulcers or urinary infection, history of urinary infection, urologic interventions or skin breakdown, and bladder and bowel incontinence. All patients with a history of chronic urinary infection or skin breakdown developed infection. In a logistic regression model, factors that were independently associated with risk of infection in the remaining patients included sex, incontinence, chronic neurologic disease, and prior urologic interventions. This review suggests rehabilitation patients are at high risk of acquiring nosocomial infection. The subgroup of patients with the highest risk of infection are identifiable by specific characteristics. 相似文献
19.
R L Tate 《Scandinavian journal of rehabilitation medicine》1987,19(1):13-18
The management of organic psychosocial deficit following severe head injury has been a neglected area of rehabilitation. Behavioural modification programmes are being utilised increasingly to ameliorate inappropriate behaviours within the rehabilitation framework. Patterns of organic psychosocial deficits in the head injured are described and issues in the management of behaviour disturbances and the constraints that operate in the application of psychological techniques to the population who suffer acquired brain damage are discussed. 相似文献
20.
The potential role of the heparin-binding growth factor pleiotrophin in breast cancer 总被引:1,自引:0,他引:1
Summary We propose that the secreted protein pleiotrophin (PTN) is a major factor in the malignant progression of breast cancer. This hypothesis is based on the growth-stimulatory effects of PTN on cellsin vitro andin vivo and on its high levels of expression in 60% of tumor samples from breast cancer patients. The stimulation of proliferation and tube formation of endothelial cells by PTN suggests that it can serve as an angiogenesis factor during tumor growth. We hypothesize that PTN has the potential to support growth of breast cancer at its primary site and to enhance the ability of tumor cells to metastasize. Furthermore, we suggest that specific endocrine signals interact to regulate the expression of PTNin vitro andin vivo. Finally, we propose that understanding the functions of PTN and its hormonal regulation can lead to the development of novel therapeutic strategies for breast cancer. 相似文献