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991.
In this paper we trace the evolution of paradigms concerning the nature of breast cancer and their therapeutic consequences. There is no doubt that the conceptual revolution of about 20 years ago has led to modest gains in survival following the use of adjuvant systemic therapy and the quality of survival by demonstrating the safety of conservative surgical regimens. At the same time, there seems to be a plateau in progress. The results of adjuvant systemic therapy are not as good as anticipated and there are a number of other inconsistencies within the conventional model of biological predeterminism that remain to be explained. We offer up an alternative paradigm that suggests that not all metastases are due to cellular dissemination with late onset local and distant recurrence resulting from a transfection phenomenon, whereby subcellular particles shed by the primary cancer cell are taken up by wandering cells of the monocyte macrophage system and transported to distant sites where the local mesenchymal cells are transfected with the genetic information that activates components of the genome to instruct these plastic cells to express the phenotypic picture of a dedifferentiated breast duct epithelial cell. Such a conceptual revolution will open up the way for a new program of research and the development of therapies based on anti-viral rather than cytotoxic drugs.  相似文献   
992.
The short tandem repeat system FES/FPS was amplified by the polymerase chain reaction (PCR) in 211 unrelated Austrians and analysed by horizontal, non-denaturing electrophoresis. The allele distribution was in Hardy-Weinberg equilibrium. No mutations were found in 25 families (50 meioses). The mean exclusion chance was 0.49, the discriminating power 0.86 and the heterozygosity rate 74.4%. Amplification could be achieved with as little as 100 pg of high molecular weight DNA, which could be reduced to 75 pg by using 32 instead of 30 cycles. By reamplifying 1 l for another 15 cycles, the threshold could be reduced to less than 20 pg. In a degradation experiment DNA extracted from bloodstains stored for up to 24 days in a moist chamber and DNA boiled for up to 18 min could be amplified.  相似文献   
993.
Most writers now recognize that mental health policy and the mental health system are extremely resistant to real changes that reflect genuine biopsychosocial paradigms of mental disorder. Writers bemoaning the intransigence of the mental health system tend to focus on a small analytical level, only to find themselves mired in the rationalities of the existing system. Problems are acknowledged to be system-wide, yet few writers have used a method of analysis appropriate for systemic problems. Drawing upon the General System Theory (GST) analytical perspective, this article advances a systematic approach to understand the mental health system and to facilitate the development of reform strategies that recognize the system's complexity and changing nature. The article first discusses the failure of major reform efforts in the mental health system and the limitations of mainstream analysis of mental health politics and policies with respect to the objectives of analysis and reform. This article describes how systems thinking has thus far influenced the study of the mental health policy and politics system, and argues that a systemic perspective is profitable for reconceiving the mental health system, enabling a fresh basis for the development of reform strategies. The mental health system should be seen as a social system influenced by larger political and economic dimensions, not just as a 'delivery system' scientifically constructed by neutral experts. Furthermore, the policy planning process should be viewed as part and parcel of a mental health system modeled as complex and dynamic. The systemic perspective outlined here should help both to clarify the value-based objectives that we hold for the system and, consequently, to plan for the strategic reforms that have so far eluded us. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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995.
This paper is drawn from a large phenomenologically based study which investigated the nursing home carers' experiences of elderly residents' sexuality. Joking and teasing with the residents was an acknowledged way for staff to deal with sexuality in the nursing home. Whilst humor can be used in a therapeutic way to establish and maintain rapport, as well as to deal with incidents which are uncomfortable, joking is also known to be an effective way to manipulate and control people. Teasing can be used as an effective strategy to discourage certain types of behavior.  相似文献   
996.
The effectiveness and transportability of multisystemic therapy (MST) were examined in a study that included 118 juvenile offenders meeting DSM-III-R criteria for substance abuse or dependence and their families. Participants were randomly assigned to receive MST versus usual community services. Outcome measures assessed drug use, criminal activity, and days in out-of-home placement at posttreatment (T2) and at a 6-month posttreatment follow-up (T3); also treatment adherence was examined from multiple perspectives (i.e., caregiver, youth, and therapist). MST reduced alcohol, marijuana, and other drug use at T2 and total days in out-of-home placement by 50% at T3. Reductions in criminal activity, however, were not as large as have been obtained previously for MST. Examination of treatment adherence measures suggests that the modest results of MST were due, at least in part, to difficulty in transporting this complex treatment model from the direct control of its developers. Increased emphasis on quality assurance mechanisms to enhance treatment fidelity may help overcome barriers to transportability.  相似文献   
997.
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999.
 In order to evaluate the effect of the introduction of recent similar guidelines on the treatment of acute urinary tract infection (UTI) in children, and possible changes in its epidemiology, we analyzed the records of hospital discharge for acute UTI under the age of 15 years in England and Wales between 1979 and 1993 and in Finland between 1978 and 1994. Cases were defined by the ICD9 diagnostic codes 590.1 (acute pyelonephritis) and 599.0 (UTI, site not specified) for males and females according to three age groups (0–4, 5–9, and 10–14 years). We also compared the registry data on kidney transplants due to end-stage renal disease caused by recurrent pyelonephritis in the United Kingdom and Finland. In England the rate of attack of symptomatic UTI per 1,000 girls under 15 years increased from 0.74 (95% confidence interval 0.71–0.76) in 1987 to 1.32 (1.29–1.35) in 1993 (P<0.001, test for trend). The respective figures for Finnish girls were 1.74 (1.62–1.86) in 1987 and 1.62 (1.51–1.74) in 1993 (P=0.72). In English boys, the increase in the attack rate was from 0.38 (0.36–0.40) in 1987 to 0.70 (0.68–0.73) in 1993 (P<0.001). In Finnish boys the respective figures were 0.74 (0.66–0.82) in 1987 and 0.88 (0.80–0.97) in 1993 (P<0.02). The observed increases in the attack rates of UTI most probably relate to increased referral of acute UTI patients to hospitals for the recommended imaging studies rather than changing occurrence. Publication of guidelines for treatment of UTI in children, consolidating more-general awareness, may have contributed to this. The mean annual numbers of kidney transplants in the United Kingdom and Finland during 1989–1995 due to end-stage renal disease caused by pyelonephritis were of similar magnitude, i.e., 1.9 (1.6–2.3) transplants per million inhabitants in the United Kingdom and 2.8 (1.5–4.7) transplants per million inhabitants in Finland. The decreasing trend in these figures in both countries, although statistically significant only in the United Kingdom (P<0.05, test for trend), suggests improved long-term outcome of these patients induced by better diagnosis and treatment of pyelonephritis and the diseases related to it, such as congenital malformations. According to our data, valid clinical guidelines are effective in changing clinical practice. Received: 1 September 1997 / Revised: 29 April 1998 / Accepted: 29 April 1998  相似文献   
1000.
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