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51.
In the introduction I express the need of introducing the point of view of Ethics when we are dealing with problems of science, technology, and especially medicine. In the first part of my presentation I deal with the problem of the value of human life, coming to the conclusion that human life might not be completely absolute, but is extremely important and “ceteris paribus” should be respected, and the problem of when it starts. Some of the main arguments are discussed. In this connection the question of abortion is briefly discussed. In the second part I deal with some problems related to human reproduction. Most people will be willing to support programmes for treating individuals with genetic disease; but at the same time the dangers of increasing depersonalization of the reproductive process are pointed out. In the third part I take up the problem of In Vitro Fertilisation. IVF has certainly brought benefits to some couples suffering from infertility, but at the same time it has raised quite a few human and moral problems. Is it permissible to fertilise an egg with a donor sperm, replacing the embryo in the womb? What about fertilising a donor egg with the husband's sperm? Is it acceptable to store or freeze embryos for future use? Is it moral to implant such an embryo in a woman who has no genetic relationship with the embryo? Is it moral to use surrogate mothers? Is it moral for ‘spare’ embryos to be killed or used as tissue for research? At the end I stress the need of dialogue between life sciences and ethics.  相似文献   
52.
53.
AIMS: To assess the utility of 99mTc tetrofosmin (TF) scintigraphy as a diagnostic modality in lymphomas. METHODS: Seventeen patients (14 with Hodgkin's disease and three with non-Hodgkin's lymphomas; age range, 10-59 years) were investigated. Planar and SPECT images of the supradiaphragmatic region (including neck and chest) were obtained. All patients were untreated at the time of the first scintigraphy. Follow-up scans after therapy were acquired in six patients (in five twice), so a total of 28 scintigraphic studies were performed. Mediastinal, pulmonary, cervical, supraclavicular and axillary activity was evaluated and results were compared in a blinded fashion with those of CT. RESULTS: TF imaging demonstrated pathological focal uptake at 38 sites (16 in the mediastinum, eight in the lungs, four in the axillae, eight in the supraclavicular region and two in the cervical region) in 16 of 17 untreated patients. CT identified 24 lesions (16 in the mediastinum, two in the lungs, two in the axillae, two in the supraclavicular and two in the cervical region) in 17 patients. Scintigraphy detected 22 of the 24 lesions demonstrated by CT and revealed 16 unknown tumor sites in 10 patients. The only negative pre-treatment scintigraphy result was found in a patient with axillary lymph node involvement. On the first post-treatment scintigrams there was a reduction in the number of visualized pathological sites (seven vs 16) in five of the six patients examined. The second follow-up study demonstrated only two lesions in two of the five patients examined. CONCLUSIONS: Our preliminary results indicate that TF imaging is effective in depicting supradiaphragmatic lymphoma lesions in untreated patients and suggest that serial scintigraphic studies may be suitable for monitoring response to treatment. However, larger series are needed to better define the possible role of TF scintigraphy in the follow-up of the response to therapy.  相似文献   
54.
In this article we would like to highlight uterine pseudoaneurysm as a cause of secondary post‐partum haemorrhage following Caesarean section. We would like to stress Doppler ultrasound scan as the initial screening modality for this condition. We also describe angioembolization as the prudent treatment option for this condition rather than resorting to surgery.  相似文献   
55.
For most of the 20th century, most drugs labeled by the United States Food and Drug Administration (USFDA) have not been adequately studied in the pediatric population. This lack of data has necessitated the continued dependence of practitioners on sub-optimal prescribing data placing pediatric patients at great risk of serious therapeutic misadventures. Recently, the USFDA has enacted and begun to enforce the Final Rule of 1997 which became effective on 1 April 1999. This rule is the culmination of the persistent efforts of numerous professional organizations, clinicians, academicians, the USFDA and others, to ensure the ready availability of appropriate data for medications intended for or that will be used in children. Unlike the 1994 Rule which voluntarily required pharmaceutical manufacturers to submit pediatric data, the Final Rule mandates submission of such data and, most importantly, empowers the USFDA to afford incentives and penalties for non-compliance including possible removal of already marketed products. This overview addresses many of the important components which must be included in the performance of a comprehensive clinical pharmacologic evaluation serving as the foundation for optimal dosing across the broad age range encompassing pediatric practice. Furthermore, the possible risk and/or benefits of the study must be reasonably defined prior to undertaking the study and clearly shared with the patient's caregivers. Consent should always be obtained from the caregiver and, when appropriate, assent obtained from the underage child. To facilitate such clinical investigations and to foster collaborative efforts with innovators and clinical research programs, the National Institutes of Health through the National Institute of Child Health and Human Development of the NIH established a network of Pediatric Pharmacology Research Units. These units have worked closely together and with other pediatric research centers to facilitate USFDA labeling of a number of commonly used medications. All of these very positive efforts highlight the many challenges that remain for the pediatric investigator and practitioner while underscoring the very positive environment in support of these efforts.  相似文献   
56.
Although exposure of LLC-PK1 epithelial cell sheets to phorbol esters (TPA) causes a near immediate and total decrease of transepithelial electrical resistance (TER), continuation of exposure for 3 to 4 days results in a tachyphylactic response as TER begins to return to control levels. Recovery of TER is maximal by 5 to 6 days, but reaches only 70 to 80% of control level. A reciprocal change in the transepithelial flux of D-mannitol indicates that the TER decrease is indicative of an increase in tight junction permeability. Exposure of cell sheets to TPA for several days also results in the appearance of multilayered polyp- like foci (PLFs) across the otherwise one cell layer thick cell sheets. The pattern of penetration of the electron dense dye, ruthenium red, from the apical surface, across the tight junction and into the lateral intercellular space indicates that the tight junctions of the cell sheet become uniformly leaky after acute exposure to TPA. However, when exposure is continued for several days, only the junctions of cells in the PLFs manifest leakiness. The decrease in TER following acute TPA exposure correlates with the translocation of protein kinase C-alpha (PKC alpha) into a membrane-associated compartment. With exposure of several days, only a trace of PKC alpha is visible by Western immunoblot, and this is in the membrane-associated compartment. Immunofluorescent microscopy indicates that the trace of PKC alpha seen in the Western immunoblots is ascribable distinctly to cells of the PLFs. Monolayer areas between PLFs show no discernible immunofluorescent signal. The data therefore indicate that tight junction barrier function may be restored in certain areas by the down regulation of PKC alpha from the membrane-associated compartment. Failure to down regulate may result in the paracellular leakiness and abnormal cell architecture of the PLFs. Possible implications of this model for in vivo epithelial tumor promotion are discussed.   相似文献   
57.
The present study was developed as part of the Integrated Research Project "New Forms of Health Work Organization: emphasis on nursing work", carried out at the University Hospital of the Rio Grande Federal University. A series of studies were carried out with the objective of identifying the occurrence, content, periodicity and vision of nursing personnel about staff meetings in order to understand the importance of holding periodic meetings. Interviews were carried out with 21 nursing professionals. Data analysis revealed two main categories: differences in vision about staff meetings among nursing personnel and dichotomy between what theory dictates and what truly happens in staff meetings.  相似文献   
58.
It is postulated that a vigorous host inflammatory response in the cystic fibrosis lung contributes to lung injury. Tumour necrosis factor-alpha (TNF-alpha) may play a part in that process and in the generation of leukotrienes. Therefore, the relationships between sputum TNF-alpha, leukotriene concentration, and lung function abnormalities in 16 children with cystic fibrosis were investigated. Each subject provided sputum samples and performed spirometry. TNF-alpha was measured by enzyme linked immunosorbent assay; individual leukotrienes were separated using high performance liquid chromatography and quantified by radioimmunoassay. The geometric mean concentration of TNF-alpha was 129.7 pg/ml and 95% confidence interval 48.2 to 348.3. Mean (SEM) leukotriene B4 (LTB4) was 97.8 (22.9) pmol/g and total cysteinyl leukotrienes were 60.9 (14.8) pmol/g. Mean (SD) forced expiratory volume in one second (FEV1) of the group was 53 (15)% of predicted and forced vital capacity (FVC) was 65 (14)% of predicted. There was a significant positive correlation between TNF-alpha and both LTB4 and the total cysteinyl leukotriene sputum content. An inverse relationship existed between TNF-alpha and FEV1 and FVC. Moreover, a negative correlation was observed between sputum LTB4 and FEV1 and FVC. These results suggest that TNF-alpha and the leukotrienes may participate in the airways inflammation and airflow obstruction observed in cystic fibrosis subjects and support the hypothesis that TNF-alpha upregulates the 5-lipoxygenase pathway in vivo.  相似文献   
59.
A new amino acid mixture for incorporation into medical foods for the treatment of hyperphenylalaninemia has been tested in a regular clinic. The mix is designed to be as unobtrusive as possible, consistent with good nutrition. After more than 1 year of trial as a beverage, we have shown that it is safe and well tolerated but that plasma phenylalanine is no better controlled than with some other products. The mix can be incorporated into a large number of different foods without affecting the taste. Occult monitoring of the quantity of medical foods purchased compared with the amounts reported to be consumed in diet histories provides an excellent way to monitor dietary compliance.  相似文献   
60.
Hodgkin's disease during pregnancy: diagnostic and therapeutic management   总被引:1,自引:0,他引:1  
OBJECTIVES: To evaluate the possibility that women affected by Hodgkin's disease (HD) during their second or third trimester of pregnancy can safely carry their pregnancy to term. METHODS: From 1986 to 1997, 6 women came to our Center during the second trimester of pregnancy and were diagnosed as having HD. Three of these 6 patients were treated with chemotherapy before delivery and 3 of them were kept under observation and started treatment after delivery. RESULTS: All 6 women gave birth to a healthy female. CONCLUSIONS: The pregnancy does not worsen the course of the illness and does not compromise long-term clinical remission and recovery.  相似文献   
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