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31.
BACKGROUND: As a result of increased interest and public demand, providing patients with adequate information about radiooncology has become more and more difficult for the doctor. Insufficient patient information can not only cause anxiety for the patient, but can also lead to legal action against the physician. In order to gain a deeper insight into our clinical practice of providing patient information, we developed a special questionnaire. We describe our first experiences in using this questionnaire at our institute. PATIENTS AND METHODS: We examined the amount of information and level of satisfaction, as well as the agreement of assessment between patient and physician after the provision of standard patient information before and at the end of radiotherapy. 51 consecutive patients were interviewed with a newly designed questionnaire. The first questioning with 13 items was carried out before radiotherapy and the second with ten items was done at the end of treatment. Sum scores for information and satisfaction were defined and agreement was measured by the weighted kappa coefficient. RESULTS: Global level of information and satisfaction was good, and a significant increase in information level and a significant decline in satisfaction were seen between questionnaire 1 and 2. Agreement between patient and physician was fair, for example intent of treatment resulted in a kappa coefficient of 0.34, and poor for the doctor's role with a kappa coefficient of -0.002. Only 52% of the patients who received palliative radiotherapy rated correctly the non-curative intent of treatment, whereas 86% of the patients who received curative radiotherapy made a correct statement. Before radiotherapy, emotional state was often both negatively and positively assessed by the patients. CONCLUSION: Our short questionnaire is simple and easy to understand. It provides insights into patient information with respect to assessment of the information, satisfaction level, and agreement between doctor and patient. Therefore, it is suitable for use in the clinical routine. We found a high information and satisfaction score, but limited agreement between physician and patient. In the future, the questionnaire can be used as an aid to evaluate patient information in everyday practice and to train the communication skills of the physician. Further evaluation of the questionnaire is needed and, in particular, the aspect of patient information with palliative radiotherapy has to be improved.  相似文献   
32.
The perinatal morbidity and mortality risk in monochorionic twin pregnancies are 3-5-fold increased compared to those of dichorionic twin pregnancies. Partially, this is due to the higher rate of preterm delivery but also to the twin-to-twin transfusion syndrome (TTTS). Caused by unidirectional blood flow via placental anastomoses, the TTTS leads to weight differences of more than 20% between monochorial twins. The blood donor often shows oligohydramnios, whereas the recipient shows polyhydramnios. Lewi et al. demonstrated, in a study with 202 monochorionic twin pregnancies, a 9% rate of severe TTTS. The mortality of this complication is about 90% when untreated. In contrast to the chronic TTTS, little is known about the acute intrapartal one, which is characterised by anaemia and hypovolaemia of the donor and polyglobulia of the recipient without significant weight differences between the two. In most cases, anaemia occurred after normal delivery of the first twin. Still, there are no means or signs for early detection. We describe the case of a 30-year-old primigravida with a monochorionic diamniotic twin pregnancy. During pregnancy, no evidence of TTTS could be detected. At 37 + 1 weeks gestation labour was induced with prostaglandin-containing gel. Both foetuses showed cephalic presentation. The CTG of the first twin showed a conspicuous heart rate. After labour the first twin presented with anaemia and hypovolaemic shock, the APGAR was 2/7/8. The infant's haemoglobin was 13.7 g/dL. After delivery, the second twin with APGAR 10/10/10 showed a haemoglobin of 19.6 g/dL, which is in the upper normal range. Their birth weights differed by merely 10.4%. Acute TTTS is frequently characterised by anaemia and hypovolaemia of the second twin. In our case of a monochorionic twin delivery with acute TTTS the donor was born first. Early diagnosis and neonatal intervention is essential for reducing postnatal morbidity and mortality.  相似文献   
33.
Stroke is a debilitating disease that affects millions each year.While in many cases cerebral ischemic in jury can be limited by effectivw resuscitation or thrombolytic treatment,the injured neurons wither in a process known as delayed neuronal death(DND).Mounting evidence indicates that DND is not simply necrosis played out in slow motion but apoptosis is triggered.Of particular interest are two groups of signal proteins that participate in apoptosis-cyclin dependent kinases(CDKs) and p53-among a myriad of signaling events after an ischemic insult.Recent investigations have shown that CDKs,a family of enzymes initially known for their role in cell cycle regulation,are activated in injured neurons in DND.As for p53,new reports suggest that its up-regulation may represent a failed attempt to rescue in jured neurons,although its up-regulation was previously considered an indication of apoptosis.These observations thus rekindle an old quest to identify new neuroprotective targets to minimize the stroke damage.In this review,the author will examine the evidence that indicates the participation of CDKs and p53 in DND and then introduce pre-clinical data to explore CDK inhibition as a potential neuroprotective target.Finally,using CDK inhibition as an example,this paper will discuss the pertinent criteria for a viable neuroprotective strategy for ischemic in jury.  相似文献   
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35.
To assess the dosimetric effect of using interpolated contours in planning intensity‐modulated radiation therapy (IMRT) for advanced T‐stage nasopharyngeal carcinoma. The present study focused on T3–T4 tumours where the proximity of targets to neurological organs poses a stringent test on the feasibility of such an approach. Contours of targets and organs were delineated on CT images of 2.5‐mm interval and a reference IMRT plan was generated. An investigative (INV) IMRT plan was then generated with the same planning protocol, but based on interpolated contours that replaced deleted contours on alternate slices. The reference and INV plans were compared. Regarding target coverage, all targets in the INV plans met the acceptance criteria except for the PTV in one case. Regarding organs, the mean dose to 1% volume of the brainstem and spinal cord in the INV plans were kept below their dose limits. No significant differences in the mean doses to others organs were found. Satisfactory target coverage and protection of critical organs to a degree similar to full‐scale contouring could be achieved with use of interpolated contours. The saving in manpower time for contouring is expected to significantly improve the throughput of the IMRT planning process.  相似文献   
36.
Background: Optomap uses the ultra‐wide field scanning laser ophthalmoscopy to provide retinal examination. It permits fundus examination without the use of a mydriatic, which is more comfortable for the patients. This paper determines the sensitivity and specificity of the Optomap for detecting retinal signs under non‐mydriatic conditions. Methods: Fifty‐four eyes identified with retinal/choroidal signs and eight normal eyes were recruited from 31 Hong Kong Chinese subjects. Photo‐documentation of fundal changes was obtained with the Optomap under non‐mydriatic conditions before a dilated fundus examination by a clinician using standard procedures. The eyelid was retracted using a cotton bud when necessary. Dilated fundus examinations were performed by another clinician using binocular indirect ophthalmoscopy and slitlamp biomicroscopy with a fundus lens. The Optomap images were evaluated by four other investigators under masked condition. The International Classification of Disease, Ninth Revision (ICD‐9‐CM) was adopted for recording retinal features. Screening results were compared with those obtained using the dilated fundus examination as the gold standard. Results: The cotton bud method for eyelid retraction showed an improvement in the area of retina that could be visualised. The sensitivity and specificity of the Optomap averaged 76.4 and 71.9 per cent, respectively. Some fundal signs were missed by all observers in the Optomap but not with the biomicroscope. These included white‐without‐pressure, lattice degeneration, paramacular drusen and pigmentary changes at central fundus. Conclusion: Optomap serves as a reliable screening tool for fundus examination especially because it covers a much wider area of the peripheral retina than other digital instruments for fundus photography.  相似文献   
37.
Dietary intake during diarrhea in children less than three years of age was estimated from information recorded on illustrated dietary forms used by children's caretakers during the first week of illness in a prospective community-based study of diarrheal diseases in Lima, Peru. The frequency of consumption and the amount consumed of food groups and selected commonly consumed foods were analyzed by the final duration of the diarrheal episode. Cereals were less frequently consumed during the acute phase of diarrheal episodes that ultimately became persistent (>14 days'duration), apparently shortening the duration of the episode by one day (median duration of four days in children not consuming vs three days in children consuming cereals during diarrhea, p <0.02 Kaplan-Meier logrank test). Only roots and tubers (mainly potatoes) were consumed in greater quantity during episodes that became persistent. There was no evidence that consumption of breast milk or non-maternal milk was associated with an alteration in diarrheal duration. This study provides further evidence of the beneficial effects of continuing feeding during diarrhea using foods available at the home level, especially cereals, which are commonly used in the diet of young children.  相似文献   
38.
Technetium-99m hexakis-2-methoxy-isobutyl-isonitrile(99mTc sestamibi) has been used for myocardial perfusion imaging in the evaluation of coronary artery disease (CAD) since 1990. The experience of its use in an Asian population with and without previous myocardial infarction (Ml), diabetes mellitus (DM), hypertension (HPT) and collateral circulation (COL) is reported. One hundred and thirty-nine patients who underwent treadmill exercise testing with 99mTc sestamibi single photon emission computed tomography (SPECT) and coronary angiogram were studied. The overall sensitivity for the detection of CAD was 91.0% and specificity was 64.7%. For patients without previous myocardial infarction, the sensitivity was 83.8% and specificity was 83.3%. Patients with COL had a higher sensitivity while those with HPT had a lower specificity. Sensitivity was higher in patients with multi-vessel disease (MVD) than single vessel disease (SVD). The overall detection for individual artery stenosis was 74.1% with a specificity of 73.1 %. Amongst the three major coronary arteries, sensitivity was highest for the right coronary artery and specificity was highest for the left circumflex artery. Specificity was higher in patients without MI or COL. We found that the agreement between 99mTc sestamibi SPECT and coronary angiogram for the extent of CAD was only 52.5%. The concordance rate was higher for patients with MVD than SVD. It is concluded that 99mTc sestamibi SPECT is a sensitive and specific test for the detection of CAD and localization of disease to individual coronary arteries in our patients with some differences in the subgroups. Agreement between coronary angiogram and 99mTc sestamibi for the extent of coronary artery disease was also satisfactory.  相似文献   
39.
For biomechanical purposes, interbody fusion cages should not dislocate, should provide high stability, and should have a low subsidence risk. Zientek (Marquardt Medzintechnik), Stryker (Stryker Implants), and Ray lumbar interbody fusion cages (Surgical Dynamics) were tested in this study. They were implanted by pairs from a posterior approach without further stabilization. In a first step, each cage design was implanted into four human L3-4 segments and extracted posteriorly under an axial preload of 200 N. In a second step, standard flexibility tests were carried out with 24 human L2-3 and L4-5 specimens in an intact condition, directly after cage implantation, and after cyclic axial compression loading (200-1000 N, 40,000 cycles, 5 Hz). In a third step, a destructive axial compression test was carried out. Maximum pullout force was highest with Ray cages (median 945 N), followed by Zientek (605 N) and Stryker cages (130 N). With all three cage designs, primary stability was higher in lateral bending and flexion than in extension and axial rotation. Implantation of Ray cages caused a decreased range of motion in all three loading directions ranging between 49% and 99%. Zientek cages only stabilized in lateral bending, flexion, and extension (45-78%) and Stryker cages in none of the three loading directions. Cyclic loading caused an increased range of motion in all cases up to 190%. Axial compression force at failure was 8413 N with Ray cages, 8359 N with Stryker cages, and 5486 N with Zientek cages. The cage design seems to influence the dislocation tendency. In this regard, threaded cages or cages with anchorage systems seem to provide more security. The stabilizing effect seems to be mainly influenced by factors such as the degree of distraction or destruction of the facet joints rather than by the cage design.  相似文献   
40.
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