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1.
P M A van Haaren H P Kok C A T van den Berg P J Zum V?rde Sive V?rding S Oldenborg L J A Stalpers M S Schilthuis A A C de Leeuw J Crezee 《International journal of hyperthermia》2007,23(3):303-314
PURPOSE: The aim of this study was to verify hyperthermia treatment planning calculations by means of measurements performed during hyperthermia treatments. The calculated specific absorption rate (SAR(calc)) was compared with clinically measured SAR values, during 11 treatments in seven cervical carcinoma patients. METHODS: Hyperthermia treatments were performed using the 70 MHz AMC-4 waveguide system. Temperatures were measured using multisensor thermocouple probes. One invasive thermometry catheter in the cervical tumour and two non-invasive catheters in the vagina were used. For optimal tissue contact and fixation of the catheters, a gynaecological tampon was inserted, moisturized with distilled water (4 treatments), or saline (6 treatments) for better thermal contact. During one treatment no tampon was used. At the start of treatment the temperature rise (DeltaT(meas)) after a short power pulse was measured, which is proportional to SAR(meas). The SAR(calc) along the catheter tracks was extracted from the calculated SAR distribution and compared with the DeltaT(meas)-profiles. RESULTS: The correlation between DeltaT(meas) and SAR(calc) was on average R = 0.56 +/- 0.28, but appeared highly dependent on the wetness of the tampon (preferably with saline) and the tissue contact of the catheters. Correlations were strong (R approximately 0.85-0.93) when thermal contact was good, but much weaker (R approximately 0.14-0.48) for cases with poor thermal contact. CONCLUSION: Good correlations between measurements and calculations were found when tissue contact of the catheters was good. The main difficulties for accurate verification were of clinical nature, arising from improper use of the gynaecological tampon. Poor thermal contact between thermocouples and tissue caused measurement artefacts that were difficult to correlate with calculations. 相似文献
2.
E M Mathus-Vliegen K van de Voorde A M Kok A M Res 《Journal of internal medicine》1992,232(2):119-127
Dexenfluramine, an effective and safe serotoninergic drug with anorectic and possible food-selection-tuning properties, was investigated in a placebo-controlled study of 1 year's duration in severe and refractory obesity. The aim of the study was to assess weight loss, and changes in cardiovascular risk factors, food intake and eating behaviour. Dexfenfluramine- and placebo-treated patients achieved a similar weight loss (greater than 10% of initial weight, by 39.5 and 30.0%, greater than 20% of initial overweight by 42.1% and 32.5% and greater than 10 kg by 41.4 and 33.3%, respectively, of the initial cohorts). Furthermore, the decreases in weight (10.7 vs. 8.0 kg), in body mass index (3.9 vs. 2.9 kg m2) and in waist/hip ratio (0.04 vs. 0.02) were not significantly different. After discontinuation of the drug, the increase in weight (2.8 vs. 1.0 kg) was significantly higher in the dexfenfluramine-treated group. Except for a borderline better effect on glucose of dexfenfluramine, both groups showed similar beneficial changes in food intake and cardiovascular risk factors. Eating behaviour in response to emotional and external stimuli was comparable in the two groups, but placebo-treated patients had to restrain their eating more in order to achieve the same weight loss. Notwithstanding the fact that weight losses and an associated amelioration of health-risk factors were of similar magnitude in dexfenfluramine- and placebo-treated patients, dexfenfluramine might have a useful role in promoting a less stressed adherence to prolonged restriction of energy intake in the severe and refractory obese subject. 相似文献
3.
RGD-based strategies for selective delivery of therapeutics and imaging agents to the tumour vasculature 总被引:12,自引:0,他引:12
Kai Temming Raymond M. Schiffelers Grietje Molema Robbert J. Kok 《Drug Resistance Updates》2005,8(6):381-402
During the past decade, RGD-peptides have become a popular tool for the targeting of drugs and imaging agents to alphavbeta3-integrin expressing tumour vasculature. RGD-peptides have been introduced by recombinant means into therapeutic proteins and viruses. Chemical means have been applied to couple RGD-peptides and RGD-mimetics to liposomes, polymers, peptides, small molecule drugs and radiotracers. Some of these products show impressive results in preclinical animal models and a RGD targeted radiotracer has already successfully been tested in humans for the visualization of alphavbeta3-integrin, which demonstrates the feasibility of this approach. This review will summarize the structural requirements for RGD-peptides and RGD-mimetics as ligands for alphavbeta3. We will show how they have been introduced in the various types of constructs by chemical and recombinant techniques. The importance of multivalent RGD-constructs for high affinity binding and internalization will be highlighted. Furthermore the in vitro and in vivo efficacy of RGD-targeted therapeutics and diagnostics reported in recent years will be reviewed. 相似文献
4.
R Harris B P Marmion G Varkanis T Kok B Lunn J Martin 《Epidemiology and infection》1988,101(3):685-694
The efficiency of the direct detection of Mycoplasma pneumoniae in respiratory exudates by an antigen capture, indirect enzyme immunoassay (Ag-EIA), has been compared with its detection with a cDNA probe ('Gen-Probe assay') directed against the specific ribosomal RNA sequences of the organism ('Mycoplasma pneumoniae Rapid Diagnostic System', Gen-Probe, San Diego, California). Both assays showed excellent specificity against a range of mycoplasma species suspended in negative nasopharyngeal aspirates; only M. pneumoniae and M. genitalium reacted. In experiments with graded doses of viable M. pneumoniae cells suspended in negative nasopharyngeal aspirate, the Gen-Probe assay was more sensitive than Ag-EIA; detection limits were respectively 2 X 10(3) c.f.u./ml (3.2 X 10(5) genomes) and 2.5 X 10(4) c.f.u./ml (4 X 10(6) genomes); detection levels 10-100 times less sensitive than culture. The two assays were also tested on nasopharyngeal aspirates or sputum specimens from 90 patients with respiratory infection; 67 of these were culture- or seronegative for M. pneumoniae and 23 were culture- or seropositive. Ag-EIA detected 21 (91%) of the latter but the Gen-Probe assay detected only 5 (22%). Both assays were negative with the 67 culture-/sero-negatives; there were no Gen-Probe assay positive/Ag-EIA negatives. Overall, it is concluded that although Ag-EIA and the Gen-Probe assay are effective substitutes for culture as a diagnostic procedure, there is a significant problem with samples which are culture-negative and from patients who have good serological evidence of current infection. Possible reasons for the disparity between the two assays are advanced. 相似文献
5.
A case of nonseminomatous testicular cancer and enlarged mediastinal lymph nodes, which were interpreted as metastases, is reported. When there was no change after two courses of chemotherapy, a mediastinoscopy was performed and the results showed sarcoidosis. 相似文献
6.
Changes in whole blood viscosity associated with hematocrit could be one of the pathways along which the cardiovascular disease (CVD) risk factors affect these diseases. Therefore, we studied in a nationwide survey comprising 514 apparently healthy Dutch elderly men and women aged 65-79 the possibility of any association between hematocrit and CVD risk factors (tobacco smoking, serum cholesterol, body mass index and blood pressure). Among men, diastolic blood pressure and total serum cholesterol were positively associated with hematocrit in both bivariate and multivariate regression analysis, whereas positive associations of hematocrit with body mass index and smoking were only significant (p < 0.05) in bivariate analysis. Among women, hematocrit was positively associated with body mass index and smoking. Except for smoking, which was associated with the mean corpuscular volume of the erythrocytes, hematocrit was positively correlated with hemoglobin and the number of erythrocytes. It is concluded that hemorrheological aspects should be considered when studying CVD among elderly people. 相似文献
7.
This paper describes the results of an asthma self-management protocol delivered to parents of children aged 0-4 years. The protocol was delivered by general practitioners (GPs), community nurses, asthma nurses, and doctors in child health centers. It consisted of 16 educational modules developed after an initial needs assessment of parents and a task analysis of primary care practitioners. The program was evaluated by means of an experimental design. Parents participating in the program had significantly more knowledge, a more favorable attitude toward asthma, and a higher self-efficacy score with respect to performing asthma self-management behaviors. Also, they reported performing self-management behaviors more frequently than parents in the control group. One-year follow-up results, which were collected for parents in the treatment group only, showed that the described changes were sustained. Further, the treatment group was found to have decreased its emergency and nonemergency use of the physician's office and to have a reduction in (reported) asthma severity. Process evaluation indicated that most modules were provided by the GPs to nearly all parents. After parents had read the modules at home, almost all the information was discussed in the next contact. GPs seldom referred patients to the community nurses, although this was suggested in the protocol. 相似文献
8.
L M Bouter O J van Rijn G Kok 《Burns : journal of the International Society for Burn Injuries》1990,16(3):198-202
The planning of health education in the prevention of burn injuries is typically incomplete and not stated explicitly, while the evaluation is executed only partially or is altogether non-existent. This article presents a theoretical framework for planning and evaluating health education for those at risk for burns. Systematic planning consists of an assessment of the magnitude and severity of the problem, an analysis of the behavioural risk factors, a study of the determinants of the most risky modes of behaviour, the design of an optimal intervention, and the implementation of this intervention. The evaluation phase deals with the effects on these five levels (implementation, intervention, determinants, behaviour and injury risk). Some common pitfalls are mentioned and special attention is given to the study of determinants of behaviour and to the design of the intervention. Furthermore, the importance of pretesting health education material is underlined. There appears to be a strong need for further research on the aetiology of burn injury and the relevant determinants of behaviour, before effective prevention can be realized. 相似文献
9.
Penile studies and heterosexual partners. Peniscopy, cytology, histology, and immunocytochemistry 总被引:2,自引:0,他引:2
M E Boon A Schneider C J Hogewoning T H van der Kwast P Bolhuis L P Kok 《Cancer》1988,61(8):1652-1659
The male partners of 20 women with human papilloma virus (HPV) infection (subtypes 6, 11, 16, and 18) were studied. These men were unsuspecting and allowed investigation "for scientific reasons" in the context of the abnormal findings in their female partners. Peniscopy (study of the penis with a colposcope) was abnormal in 17 cases. In the cytologic-brush preparations of the urethra, hyperkeratosis (visualized with the modified Papanicolaou technique) occurred in all cases, but koilocytosis in only one. Both urothelial cells and squamous cells in the urethral samples were positive for HPV, as shown in the immunocytochemistry. In the histologic sections taken from flat lesions there was hyperkeratosis, dyskeratosis, and abnormal nuclear maturation. The authors concluded that, using simple techniques, subtle disturbances in maturation of nuclei and cytoplasm can be established in penile epithelium of these sexual partners. Similar changes are established in other HPV lesions. It seems likely that a significant proportion of the male population is infected in countries were HPV an important factor in cervical carcinogenesis. 相似文献
10.
Kok Yvette J.M.de; Merkx Gerard F.M.; van der Maarel Silvere M.; Huber Irene; Malcolm Susan; Ropers Hans-Hilger; Cremers Frans P.M. 《Human molecular genetics》1995,4(11):2145-2150
X-linked deafness with stapes fixation (DFN3) is caused by mutationsin the POU3F4 gene at Xq21.1. By employing pulsed field gelelectrophoresis (PFGE) we identified a chromosomal aberrationin the DNA of a DFN3 patient who did not show alterations inthe open reading frame (ORF) of POU3F4. Southern blot analysisindicated that a DNA segment of 150 kb, located 170 kb proximalto the POU3F4 gene, was duplicated. Fluorescence in situ hybridization(FISH) analysis, PFGE, and detailed Southern analysis revealedthat this duplication is part of a more complex rearrangementincluding a paracentric inversion involving the Xq21.1 region,and presumably the Xq21.3 region. Since at least two DFN3-associatedminideletions are situated proximal to the duplicated segment,the inversion most likely disconnects the POU3F4 gene from aregulatory element which is located at a distance of at least400 kb upstream of the POU3F4 gene. 相似文献