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Liverpool, a seaport in NW England, suffered severely from lethal infectious diseases in the second half of the 19th century: the population was densely crowded and malnourished and life expectancy was low. Time-series analysis shows that the epidemics of whooping cough (i) had an interepidemic interval of 2.9 years, 1863-85, which lengthened to 3.4 years, 1885-1900 (ii) were strongly coherent with wheat prices (P < 0.001) and (iii) also correlated with cycles of seasonal weather conditions. It is suggested from mathematical modelling that the epidemics in this compromised population were maintained (i.e. the system was driven) by an oscillation of malnutrition and by seasonal weather conditions. A model that incorporates both the dynamics of whooping cough and the demographic characteristics of the population is presented. It has been shown to replicate the dynamics of the epidemics and has been used to predict the changes with time of (i) the force of the infection and (ii) the proportion of those infected with whooping cough who died.  相似文献   
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Updated information on the pathologic characterization and treatment of olfactory neurobiastoma (ON) and neuroendocrine carcinoma (NEC) diseases is presented. A series of patients with ON or NEC was evaluated and retrospectively staged using the UCLA system. The parameters evaluated were symptoms, age, sex, risk factor assessment, stage of disease, treatment, and clinical outcome. The median follow-up was 3 years (range, 18 months to 23 years). The predominant therapy (63%) for ON was combined surgery and radiotherapy. Surgery alone or in combination with ancillary treatment was used in 58% of patients with NEC. For the most receat years of the study, patients with NEC have been treated successfully with combined chemotherapy and radiotherapy. Seventy percent of the patients with ON and 75% of the patients with NEC were clinically free of disease during the defined follow-up period. Surgical therapy consisting of a craniofacial resection combined with postoperative radiotherapy has resulted in good local and long-term control of ON. Our experience indicates that combined chemoradiation is an appropriate therapeutic approach for NEC.  相似文献   
104.
Mildly elevated maternal plasma homocysteine (Hcy) levels (hyperhomocysteinemia) have recently been observed in some neural tube defect (NTD) pregnancies. Plasma levels of Hcy are governed by both genetic and nutritional factors and the aetiology of NTDs is also known to have both genetic and nutritional components. We therefore examined the frequency of relatively common mutations in the enzyme cystathionine β-synthase (CBS), which is one of the main enzymes that controls Hcy levels, in the NTD population. Neither the severely dysfunctional G307S CBS allele nor the recently reported 68 bp insertion/I278T CBS allele was observed at increased frequency in the cases relative to controls. We therefore conclude that loss of function CBS alleles do not account for a significant proportion of NTDs in Ireland.  相似文献   
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This paper, written by two male nurse teachers, describes and analyses their experience of working in a nurse education culture permeated by the philosophy of business management The introduction of business management practices to nurse education is discussed as a reflection of the current political hegemony of market forces and individualism The authors discuss the implications for nurse teachers of being continually exposed to these politically motivated forces which increasingly provide the paradigm for service developments within the United Kingdom health services In discussing the impact of this exposure it is argued that at the personal level individual teachers are experiencing a degree of apathy and personal dissonance which undermines their professional value system, resulting in emotional distress and a crisis of identity It provides a critical reflection on the way organizational dynamics and power relations influence the subjective sense-making of individuals The authors use a multiplicity of perspectives, including those provided by individual psychology, power relations, feminism and personhood, to argue for the need to develop an alternative paradigm which is characterized by the valuing of individual persons, empathic sensitivity and the fostering of creativity been important to us from a personal and professional  相似文献   
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BACKGROUND: Routine cytomegalovirus (CMV)-pp65 antigenaemia monitoring shows that some patients will develop pp65 antigenaemia during valaciclovir prophylaxis or after cessation of treatment. The aim of this pilot study was to evaluate the safety and efficacy of lowering immunosuppression in kidney transplant recipients who exhibit mildly symptomatic CMV infections while on valaciclovir prophylaxis. METHODS: We selected 12 patients who experienced mildly symptomatic CMV infections defined as a positive CMV-pp65 antigenaemia test associated with either neutropenia, asthenia or arthralgia, but no fever. All of them received prophylaxis with valaciclovir for at least 3 months. Testing for CMV-pp65 antigenaemia was performed weekly for 6 months. RESULTS: The mildly symptomatic infections occurred at a median interval of 69 days after transplantation-during prophylaxis in eight cases and after valaciclovir discontinuation in the other four cases. All of them were effectively managed by lowering immunosuppressive therapy, leading to the disappearance of symptoms and CMV antigenaemia reduction. No immunological complication or recurrence of CMV infection or disease was noted. I.v. ganciclovir never became necessary. CONCLUSION: The mildly symptomatic CMV infections occurring in valaciclovir-treated patients may be managed efficiently and without immunologic complication by lowering immunosuppressive therapy.  相似文献   
109.
BACKGROUND CONTEXT: The injection of various solutions aimed at producing a sclerosing effect has been used to treat soft tissues injuries (eg, inguinal hernia) for more than 100 years. In the 1930s, this treatment approach was applied to injured joints in an attempt to stimulate connective tissue repair. Although several studies have been published about this method of treatment for various orthopedic and spinal indications (termed prolotherapy), its use remains controversial. PURPOSE: To conduct a critical review of the literature on prolotherapy for spinal pain. STUDY DESIGN/SETTING: Critical review of the literature. METHODS: Computerized medical literature databases (Medline, CINAHL, Mantis, Cochrane Central Register of Controlled Trials) were searched to uncover all published information about the use of sclerosing injections in humans with spinal pain disorders. Search results were reviewed for relevance, and information was abstracted from full-text articles. RESULTS: Our search uncovered almost 200 reference materials in various media related to prolotherapy, including 31 clinical studies related to spinal pain. There were 26 observational cohorts and 5 randomized clinical trials (RCTs). Indications in these studies were low back pain (22), neck pain (3), cervical headaches (3) and dorsal or thoracic pain (3). A total of 20 sclerosing solutions were used in these studies; the most common was a mixture of dextrose 12.5%, glycerin 12.5%, phenol 1.25% and lidocaine 0.25%. Wide variations were found in treatment protocols, such as dose, number of treatments and use of adjunct therapies. Most cohort studies were only of moderate quality and varied greatly in the substances injected and the use of co-interventions. Most clinical studies reported positive results such as decreased pain or disability, although differences between treatment and control groups did not always reach statistical significance. Commonly reported adverse reactions to this treatment include temporary postinjection pain and stiffness. A handful of more serious adverse events were reported in the 1950s and 1960s with stronger or unknown solutions. CONCLUSION: Prolotherapy describes a variety of treatment approaches rather than a specific protocol. Results from clinical studies published to date indicate that it may be effective at reducing spinal pain. Great variation was found in the injection and treatment protocols used in these studies that preclude definite conclusions. Future research should focus on those solutions and protocols that are most commonly used in clinical practice and have been used in trials reporting effectiveness to help determine which patients, if any, are most likely to benefit from this treatment.  相似文献   
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