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81.
J A Gietema M T Meinardi D T Sleijfer H J Hoekstra W T A van der Graaf 《Annals of oncology》2002,13(10):1616-1620
BACKGROUND: The routine follow-up of patients with disseminated non-seminomatous testicular cancer (DNSTC) treated with the combination of orchidectomy, polychemotherapy, and if needed, resection of the residual mass, consists of regular physical examinations, chest X-rays (CXR) and tumor marker assessments. Most guidelines for this routine follow-up originate from multi-center trials. In order to estimate the value of CXR in the detection of tumor relapse after complete remission, we reviewed all patients with disseminated testicular cancer treated with chemotherapy at the University Hospital Groningen. PATIENTS AND METHODS: Three hundred and fifty-three consecutive patients with DNSTC treated between February 1977 and February 1999 at our institution were reviewed. Two hundred and ninety (82.2%) patients, who were in complete remission after cisplatin-containing chemotherapy followed by, if necessary, resection of the residual mass, entered this analysis. The follow-up schedule consisted of regular physical examinations, tumor marker assessment (lactate dehydrogenase, beta-human chorionic gonadotropin and alpha-FP) and CXR. In all patients the first diagnostic sign of tumor relapse was documented. RESULTS: During a median follow-up of 107 months (range 8-261) a tumor relapse was documented in 33 patients (11.4%). Median time to relapse was 17 months (range 6-179) after the start of chemotherapy. In 27 patients, tumor relapse was first detected by a rise in tumor markers. Two patients presented their relapse with neurological complaints. Both were diagnosed with brain metastasis. In four patients the relapse was detected by both increase in tumor markers and abnormalities in the physical examination. In none of the 33 relapsed patients was routine CXR during follow-up involved in the detection of tumor recurrence. All but one of the relapsed patients had elevated tumor markers before the start of chemotherapy. The total number of CXR made during follow-up in all 290 patients was 10 160; none were diagnostic for the detected relapses. CONCLUSIONS: These data suggest that routine CXR has no additional value in the detection of tumor relapses during follow-up after chemotherapy in the subset of patients who present their DNSTC with increased tumor markers and are in complete remission after treatment. In order to save valuable resources, CXR can be omitted from the follow-up schedule after chemotherapy for marker-positive non-seminomatous testicular cancer in complete remission. 相似文献
82.
The effect of chemotherapy on the growing skeleton 总被引:3,自引:0,他引:3
With the increasing use of high dose (poly)chemotherapy schedules in the treatment of childhood cancer it is particularly important to know the adverse effects of these treatments. Growth is a complex mechanism affected not only by chemotherapy but also by the malignancy itself as well as nutritional status, the use of corticosteroids and (cranial) radiation. In vitro and animal studies are often the most useful in determining the effect of a single chemotherapeutic agent on the growing skeleton. In vitro studies have shown doxorubicin, actinomycin D and cisplatin to have a direct effect on growth plate chondrocytes that in animals results in decreased growth and final height. Clinical studies with multiagent chemotherapy have demonstrated that antimetabolites decrease bone growth and final height. Childhood cancer survivors are at risk of a reduced bone mineral density, mainly due to methotrexate, ifosfamide and corticosteroids. This reduced bone mineral density persists into adult life and may increase bone fracture risk at an older age. 相似文献
83.
Jacobus D. M. Herscheid Arend Hoekstra Cornelis M. Vos 《European journal of nuclear medicine and molecular imaging》1984,9(11):508-510
N-Succinyldesferrioxamine B was found to be cleared very fast by the kidneys. Since this compound can strongly chelate several metals, including the generator-produced isotopes 113mIn and 68Ga, 67Ga-N-succinyldesferrioxamine B (SDF) was tested as a substitute for 131I-o-iodohippuric acid (OIH) in the measurement of renal tubular secretion. In rats both compounds showed similar biodistribution patterns with a greater excretion rate of SDF. In rabbits, however, the excretion rate of OIH was superior to that of SDF. Inhibition of tubular secretion by probenecid was nearly ineffective in the renal clearance of both OIH and SDF. 相似文献
84.
Charles J. Vecht Hanny Haaxma-Reiche Evert M. Noordijk George W. Padberg Joan H. C. Voormolen Foppe H. Hoekstra Joseph Th. J. Tans Nanno Lambooij Jan A. L. Metsaars A. Rolf Wattendorff Ronald Brand Jo Hermans 《Annals of neurology》1993,33(6):583-590
Most patients treated for single or multiple brain metastases die from progression of extracranial tumor activity. This makes it uncertain whether the combination of neurosurgery and radiontherapy for treatment of single brain metastasis will lead to better results than less invasive treatment with radiotherapy alone. The effect of neurosurgical excision plus radiotherapy was compared with radiotherapy alone in a prospectively randomized trial with 63 evaluable patients with systemic cancer and a radiological diagnosis of single brain metastasis. Radiotherapy was given to the whole brain by a novel scheme of 2 faractions per day of each 2 Gy for a total of 40 Gy. Before randomization, patients were stratified by site (lung cancer vs nonlung cancer) and status of extracranial disease (progressive vs. stable). Survival as such and functionally independent survival (FIS; defined as world Health Organization performance status ≤ 1 and neurological funcition ≤ 1) were compared between both treatment arms. The combined treatment compared with radiotherapy alone led to a longer survival (p =0.04) and a longer FIS (p=0.06). This was most pronounced in patients with stable extracranial disease (median survival, 12vs 7 mo; median FIS 9 vs 4 Mo). Patients with progressive extracranial cancer had a median overall survival of 5 months and a FIS of 2.5 months irrespective of given treatment. Improvement in functional status occurred more rapidly and for longer periods of time after neurosurgial excision and radiotherapy than after radiotherpy alone. Patients older than 60 years had a hazard ratio of dying of 2.74(p=0.001) compared with younger patients, but in both age groups the combined treatment did better then radiotherapy alone. We coclude that patients with single brain metastasis and stable extracranial tumor activity should be treated with surgical excision and radiotherapy. For patients with progressive extracranial disease during the previous 3 months, radiotherapy alone appears to be sufficient. After treatment of single brain metastasis, parients remain functionally independent until a few months before death. 相似文献
85.
86.
No evidence of in vitro and in vivo porcine endogenous retrovirus infection after plasmapheresis through the AMC-bioartificial liver 总被引:5,自引:0,他引:5
87.
A focus of increased uptake on a 201Tl minus 99mTc subtraction scintigram of the parathyroid glands was found in a patient with persistent hypercalcemia. This area was not caused by an abnormal parathyroid gland but by an enlarged lymph node containing metastatic tissue from an adenocarcinoma of the ovary. 相似文献
88.
Maier O van der Heide T van Dam AM Baron W de Vries H Hoekstra D 《Molecular and cellular neurosciences》2005,28(2):390-401
Remyelination, as potential treatment for demyelinating diseases like multiple sclerosis (MS), requires the formation of new axoglial interactions by differentiating oligodendrocyte progenitor cells. Since the oligodendrocyte-specific isoform of neurofascin, NF155 (neurofascin isoform of 155 kDa), may be important for establishing axoglial interactions, we analyzed whether its expression is changed in chronic relapsing experimental allergic encephalomyelinitis (EAE). Although overall expression of NF155 was not changed, immunoreactivity of NF155 was dramatically increased in EAE lesion sites indicating an enhanced accessibility of NF155 epitopes. As this may be due to infiltrating plasma components, for example, fibronectin, we analyzed whether fibronectin affects the intracellular distribution and membrane association of NF155 in primary oligodendrocytes. In oligodendrocytes cultivated on polylysine, NF155 was recruited to membrane microdomains (rafts) during development and became enriched in secondary and tertiary processes. Fibronectin perturbed localization and raft association of NF155 and inhibited the morphological differentiation of oligodendrocytes. Consistent with the in vitro data, raft association of NF155 was reduced in spinal cord of EAE rats. The results suggest that the association of NF155 to microdomains in the oligodendrocyte membrane is required for its participation in intermolecular interactions, which are important for myelination and/or myelin integrity. 相似文献
89.
Meurs I Hoekstra M van Wanrooij EJ Hildebrand RB Kuiper J Kuipers F Hardeman MR Van Berkel TJ Van Eck M 《Experimental hematology》2005,33(11):1309-1319
OBJECTIVE: Scavenger receptor class B, type I (SR-BI) is a multifunctional receptor that promotes the selective uptake of cholesteryl esters from high-density lipoprotein (HDL). Disruption of SR-BI in mice results in a dramatic increase in HDL cholesterol. Interestingly, mice lacking SR-BI also develop anemia, as evidenced by accumulation of reticulocytes in the circulation. The objective of the current study was to delineate the mechanism underlying development of anemia in the absence of SR-BI. METHODS: Expression of important mediators of erythropoiesis, as well as key enzymes in the degradation of erythrocytes, were analyzed using real-time polymerase chain reaction in SR-BI wild-type and SR-BI knockout mice. In addition, in vivo studies were performed using biotinylated erythrocytes to determine erythrocyte survival. RESULTS: mRNA expression of TAL-1, GATA-1, FOG-1, erythropoietin receptor, and ferrochelatase, important mediators of erythropoiesis, was increased in spleens of SR-BI-deficient mice. In addition, the relative amount of early Ter119(high)CD71(high) -expressing erythroblasts was increased in SR-BI-deficient spleens. Interestingly, also expression of hemeoxygenase 1 and biliverdin reductase, enzymes involved in the degradation of erythrocytes, was increased. Furthermore, an elevated amount of conjugated bilirubin, the breakdown product of hemoglobin, was found in bile. Using biotinylated erythrocytes, we show that survival of erythrocytes was decreased in SR-BI-deficient mice. Thus, the observed increased erythropoiesis in the SR-BI-deficient mice is most likely a direct response to the reduced erythrocyte lifespan. Finally, we show that increased HDL cholesterol levels due to SR-BI deficiency induce erythrocyte cholesterol:phospholipid ratios, resulting in decreased deformability and increased osmotic fragility, thereby providing an explanation for the observed reduced lifespan. CONCLUSIONS: SR-BI is not only essential for HDL cholesterol homeostasis and atherosclerosis susceptibility, but also for maintaining normal erythrocyte lifespan. 相似文献
90.
Hoekstra JH Szajewska H Zikri MA Micetic-Turk D Weizman Z Papadopoulou A Guarino A Dias JA Oostvogels B 《Journal of pediatric gastroenterology and nutrition》2004,39(3):239-245
OBJECTIVE: A randomized, double-blind, placebo-controlled multicenter study to evaluate efficacy and safety of a mixture of non-digestible carbohydrates (NDC) as an adjunct to oral rehydration therapy in treatment of acute infectious diarrhea in children with mild to moderate dehydration. METHODS: 144 boys aged 1 to 36 months with diarrhea defined as three or more watery stools per day for >1 day but <5 days with mild or moderate dehydration (World Health Organization criteria) were randomly assigned to receive hypotonic oral rehydration solution (ORS) (Na 60 mmol/L, glucose 111 mmol/L) with or without a mixture of NDC (soy polysaccharide 25%, alpha-cellulose 9%, gum arabic 19%, fructooligosaccharides 18.5%, inulin 21.5%, resistant starch 7%). RESULTS: Intention-to-treat analysis did not show significant differences in mean 48 hour stool volume (ESPGHAN-ORS with NDC versus ESPGHAN-ORS, 140 +/- 124 g/kg versus 143 +/- 114 g/kg; P = 0.41). Duration of diarrhea after randomization was similar in both groups (82 +/- 39 hours versus 97 +/- 76 hours, P = 0.24). There were no significant differences in the duration of hospital stay (111 +/- 44 hours versus 126 +/- 78 hours; P = 0.3). Unscheduled intravenous rehydration was similar in both groups (21.4% versus 16.2%, P = 0.42). CONCLUSION: In boys with acute non-cholera diarrhea with mild to moderate dehydration a mixture of non-digestible carbohydrates was ineffective as an adjunct to oral rehydration therapy. 相似文献