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71.
We describe a 61-year-old patient with primitive neuroectodermal tumor (PNET) arising from the kidney. Despite intensive treatment including surgery, combination chemotherapy and radiotherapy, rapid progression of the tumor was encountered and the patient died within six months with widespread disease. This appears to be the first recorded case of PNET of the kidney. © 1994 Wiley-Liss, Inc.  相似文献   
72.
Much work remains to be done to establish the clinical usefulness of the RFI for early diagnosis and treatment guidance. The discoveries obtained by functional optical imaging of the neocortex in the last 15 years and the recent RFI studies of the eyes of normal subjects and patients with diabetic retinopathy, glaucoma, and age-related macular degeneration suggest that functional optical imaging of the retina is likely to become a multi-modality powerful clinical tool.  相似文献   
73.
Danielle Ofri     
Ofri D 《Lancet》2003,361(9368):1572
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74.
The human myeloid leukemia cell line HL-60 transports the oxidized form of ascorbic acid, dehydroascorbic acid (DHA), and accumulates reduced ascorbic acid. We studied the effect of ascorbic acid loading on apoptosis induced by serum- and glucose-free culture and by oxidative stress induced by H2O2. Uptake accumulation studies indicated that incubation of HL-60 cells with DHA resulted in the accumulation of intracellular ascorbic acid which decreased with time when cells were incubated in DHA-free medium. Exposure of HL-60 cells to increasing concentrations of H2O2 resulted in dose-dependent intracellular accumulation of peroxides, as determined by the use of the oxidation-sensitive fluorescent probe 2',7'-dichlorofluorescin-diacetate (DCFH-DA), which was accompanied by a decrease in intracellular ascorbic acid and an increase in apoptosis. A dramatic decrease in intracellular ascorbic acid was noted when preloaded HL-60 cells were exposed to 150 microM H2O2 (the concentration dropped from 5.2 +/- 0.6 mM to 3.6 +/- 0.1 mM in cells preincubated with 150 microM DHA). A dose-dependent protective effect of DHA was observed. Ascorbic acid loading also provided strong protection from apoptosis associated with serum- and glucose-free culture. Flow cytometry studies showed that exposure of HL-60 cells to 150 microM H2O2 resulted in decreased Bcl-2 expression that was associated with enhanced apoptosis (up to 33.6 +/- 2.6%). No significant variation of Bcl-2 expression was measured following exposure of HL-60 cells, loaded with ascorbic acid, to 150 microM H2O2 and only a slight increase (up to 10.1 +/- 3.1%) in apoptosis. These findings indicate that ascorbic acid can inhibit apoptosis induced by oxidative stress in HL-60 cells.  相似文献   
75.
Reflection photoplethysmography allows noninvasive recording of arterial-blood-volume pulses. The method is based on monitoring backscattered infrared light and has promising diagnostic value: volume pulse shapes depend on cardiac performance and arterial elasticity. The poor repooducibility of photoplethysmograms at repeated trials on the same subject impairs their usefulness, however. The actual formation of photoplethysmograms was invastigated using agar blocks with blood-filled vessels embedded in them. Two optical processes were observed: (a) Attenuation by the vessel of backscattered and back-reflected light, here vessel extension leads to ‘less’ light at the sensor;(b) Light reflection by the vessel wall proximal to the sensor, and vessel extension gives rise to ‘more’ light at the sensor, this counteracts the attenuation. The combined effects of (a) and (b) make the recorded pulse shape dependent on the transducer/artery position relationship. Volume-pulse transducers that monitor the displacement of arterial walls mechanically (e.g. piezoelectric crystals) are liable to produce similar artefacts. The prospects of minimising these artefacts, by using improved transducer designs, are promising. Partly supported by the Joint Research Fund of the Hebrew University and Hadassah  相似文献   
76.
Neurons are highly polarized cells with axons that innervate distant targets.The distance of subcellular compartments from the nucleus requires sophisticated tr...  相似文献   
77.
This article, through presentation of case studies, defines differences and suggests separate definitions for the terms cosmetic dentistry and esthetic dentistry. Dentistry strives to emulate harmonious form and function for therapy, and modification of appearance is an integral part of dental treatment. Cosmetic dentistry suggests a certain accommodation and is a compromise of current technology. Cosmetic dentistry is commonly selected as an interim procedure that does not necessarily function ideally and does not always emulate the pristine state of a natural dentition. Esthetic dentistry requires less accommodation, incorporates acceptable biologic technology for long-term survival, functions suitably, and mimics the pristine state of the natural dentition. Cosmetic and esthetic dentistry are different in definition, concept, and execution.  相似文献   
78.
79.
BACKGROUND: A substantial excess risk of certain malignancies has been demonstrated after organ transplantation. Immunosuppressive treatment to prevent allograft rejection is probably the main cause. METHODS: We reviewed retrospectively all medical records of the 121 patients that underwent lung and heart-lung transplantation from 1992 until December 2004. We compared our results to the International Society for Heart and Lung Transplantation (ISHLT) registry data and previous reports concerning lung transplantation. RESULTS: 102 of the 121 patients survived for 3 months to 12 years. Malignancies developed in 16 patients, as follows: lymphoproliferative disorder in 3, Kaposi's sarcoma in 3, other nonmelanoma skin cancers in 7, urinary bladder transitional cel carcinoma in 3, and colon cancer in 1. Patients with malignancy were older at transplantation than those without (mean +/- SD, 54.1+/-7.8 vs. 49.5+/-14.2 years; P=0.03). Fourteen had smoked in the past. Four died of bronchiolitis obliterans. In comparison with the ISHLT, we observed more skin cancer and transitional cell carcinoma (12.8% vs. 0.7% and 3.8% vs. 0.03%, respectively) and a similar frequency of posttransplant lymphoproliferative disease. CONCLUSIONS: We conclude that malignancy is a common complication after lung transplantation. In Israel, which is sunny most of the year, skin cancers and transitional cell carcinoma of bladder are more common. Modification of the immunosuppression late posttransplantation may reduce the risk of cancer. Patients should also be counseled to avoid sun exposure and ensure adequate hydration.  相似文献   
80.
OBJECTIVE: Many patients with erectile dysfunction (ED) stop using sildenafil due to subjective failure. This study examined whether counseling and maximal dosing (100 mg) could achieve better treatment compliance and could possibly improve treatment outcome. MATERIAL AND METHODS: Patients were recruited by newspaper advertisements and referred to 5 ED centers throughout the country. Details about their previous experiences with sildenafil were recorded and following an explicit explanation about the nature and action of the drug, were offered to enter the study. Instructions on drug use were provided during each visit in which four 100 mg Sildenafil tablets were provided. Treatment outcomes were assessed by the international index of erectile function (IIEF) questionnaire after taking 4 and 8 tablets. In 2 ED centers a short video with sexual counseling content was added in between visits. RESULTS: The study cohort was comprised of 220 patients aged 27-88 years. The majority reported having received limited or no instructions on drug use when sildenafil was first prescribed. A significant increase in IIEF erectile function domain scores (EFDS) between visits 1, 2 and 3 was observed (10.96+/-0.40, 16.73+/-0.51 and 17.82+/-0.55 mean+/-SE, respectively), with 23.6% of the study patients achieving normal erectile function at the end of the study. The parameters of age and initial severity of ED most influenced treatment success. CONCLUSIONS: Counseling and dose adjustment were directly influential in achieving an excellent response to a second trial of sildenafil in patients with ED who had previously failed treatment with the drug, and obviated their needing to seek more invasive measures.  相似文献   
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