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41.
E mu-pim-1 transgenic mice are predisposed to develop lymphomas. Due to their low spontaneous tumour incidence and their increased sensitivity towards the lymphomagen ethylnitrosourea these mice may present an interesting model for short-term carcinogenicity testing. Here, we report on the further exploration of this transgenic mouse model with two additional carcinogens known to have, among others, the lymphohaematopoietic system as target, i.e. benzo[a]pyrene (B[a]P) and 12-O-tetradecanoylphorbol-13-acetate (TPA). B[a]P, given three times a week (by gavage) for 13 weeks at 4.3, 13 or 39 mg/kg body weight, resulted in a dose-related increase in lymphomas up to a 90% incidence in E(mu)-pim-1 mice during the observation period of 40 weeks. B[a]P also induced tumours of the forestomach within this observation period, though at a lower incidence and apparently equally effective in wildtype and transgenic mice. TPA, on the other hand, was unable to induce lymphomas (or tumours in any other organ) in either transgenic or wildtype animals within the observation period of 44 weeks, when applied dermally at the maximum tolerated dose of 3 microg/mouse, twice a week for 35 weeks. Molecular analysis showed that B[a]P-induced lymphomas in transgenic mice were of T-cell origin, 80% of which had elevated levels of c-myc expression. None of the lymphomas had increased N-myc expression and mutation analysis of the ras-gene family revealed a K-ras mutation in only one out of eight tumours investigated. Also, none of the lymphomas showed aberrant expression of p53 as determined by immunohistochemistry. It is concluded that the E mu-pim-1 mouse model will not be very suitable for short-term carcinogenicity testing in general: only genotoxic chemicals that have the lymphohaematopoietic system as target for carcinogenesis in wild- type mice, appear to be efficiently identified.   相似文献   
42.
Mucormycosis is a rare fungal infection of childhood, occurring mainly in patients with chronic illnesses such as diabetes and malignancies. The fungus seldom grows in culture and confirmation of the diagnosis depends on histologic examination of infected tissues. To date, the reported natural history of the disease has been rapid progression and a fatal outcome. Therefore, the importance of early diagnosis by tissue biopsy and early treatment with surgical debridement and systemic antifungal therapy cannot be overemphasized. The pulmonary system is the most common site for mucormycosis in patients with leukemia. We report what we believe to be the first successfully treated case of isolated muscular mucormycosis occurring in a child with biphenotypic acute leukemia. The diagnosis was made promptly by tissue examination at the time of surgical debridement. The patient was also given systemic amphotericin-B therapy.   相似文献   
43.
Data on body composition in conjunction with reference centiles are helpful in identifying the severity of growth and nutritional disorders in infancy and for evaluating the adequacy of treatment given during this important period of rapid growth. Total body fat (TBF) and fat-free mass (FFM) were estimated from total body electrical conductivity (TBEC) measurements in 423 healthy term Caucasian infants, aged 14-379 days. Cross sectional age, weight, and length related centile standards are presented for TBF and FFM. Centiles were calculated using Altman's method, based on polynomial regression and modelling of the residual variation. The TBF percentage steeply increased during the first half year of life, and slowly declined beyond this age. Various simple TBEC derived anthropometric prediction equations for TBF and FFM are available to be used in conjunction with these standards. Regression equations for the P50 and the residual SD, depending on age, weight, or length, are provided for constructing centile charts and calculating standard deviation scores.  相似文献   
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Concepts necessary to an understanding of the basics of quality assurance audits are presented. Included are specific examples that bridged theory and practice by applying the protocol to a real-life diagnostic imaging situation. This method meets the present requirements of the Joint Commission of the Accrediation of Hospitals.  相似文献   
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Two patients had colonic perforation as a result of percutaneous nephrostomy placement followed by track dilatation and renal calculus removal. We present the technical aspects of nephrostomy placement and stone removal, as well as the clinical diagnosis and management of these cases. Both patients recovered well with conservative therapy and required no surgical intervention. This report reviews the anatomic considerations for percutaneous nephrostomy in patients undergoing renal stone removal.  相似文献   
49.
The nature of remembrance of traumatic events has been particularly controversial during the past decade as vigorous new research has reshaped thinking about trauma and memory. Memory alterations in traumatized individuals have been investigated within both theoretical and biological frameworks. There are different types of memory, and empirical studies have associated post-traumatic stress disorder (PTSD) with a simultaneous weakening and a strengthening of memory. Memory deficiencies in PTSD have been found to be related to problems in new learning (explicit memory), but other specific deficiencies are unvalidated. Recently, accuracy of memory has received particular scrutiny because considerable importance is attached to victims' recollections. In 1998, at the International War Crimes Tribunal in The Hague, The Netherlands, a Bosnian-Croatian soldier was tried for aiding and abetting the rape of a Muslim woman. The defendant's lawyers suggested that the woman's memory was inaccurate, having been adversely affected by her traumatic experiences, and that the defendant whom she identified was not present during her interrogation and abuse. The prosecution disagreed and argued that memories of traumatic experiences in individuals with PTSD are characteristically hyperaccessible. Expert witnesses on both sides were brought in to provide medicolegal testimony about the scientific parameters of stress and its long-term effects on brain regions associated with memory. With the expert witness discussion as background, this article reviews the most recent research about the nature of memory in the aftermath of trauma and the politics of psychological trauma and the law.  相似文献   
50.
Physician Orders for Life-Sustaining Treatment (POLST) form provides choices about end-of-life care and gives these choices the power of physician orders. The POLST form assures end-of-life choices can be implemented in all settings, from the home through the health-care continuum. The use of the POLST form was evaluated in a pilot study in nursing homes in two eastern Washington counties. Chart reviews and template analysis of interviews revealed the POLST form accurately conveyed end-of-life wishes in 19 of 21 cases. An informed consent process was evidenced in 16 of 21 cases, and the POLST form was congruent with residents' existing advance directives for health care. The findings support the continued use, development, and evaluation of this promising tool for improving end-of-life care.  相似文献   
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