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Biostatisticians play an important role in medical research. They are co-responsible for an appropriate and efficient study design, they are involved in monitoring the study conduct, they plan and perform the data analysis, and they are involved in interpreting and publishing the results. However, how are the biostatisticians prepared for their tasks and responsibilities? Graduate programs in biostatistics are being offered, but some practicing biostatisticians completed their studies in a mathematical or epidemiological program, or obtained their degree in subject-specific fields (such as medicine or biology). Therefore, the expertise and the competencies can vary widely between the individual biostatisticians, also depending on the application field. In this article, focusing on European and US practices, we discuss the required professional expertise for the main areas of applications in the medical field as well as the necessary soft skill competencies of a biostatistician.  相似文献   
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PURPOSE: To evaluate the pattern of neurological late effects in patients who have received surgery only for a brain tumor in childhood and to identify possible risk factors for neurological sequelae. PATIENTS AND METHODS: The medical, histologic, and operative records were reviewed for 65 consecutive patients operated for a benign brain tumor from 1970 to 1997, and all patients were re-examined after a median length of follow-up of 10.7 years. Thirty-four patients had posterior fossa tumors, 22 patients had cerebral hemisphere tumors, and nine patients had midline tumors. RESULTS: At the time of follow-up, 20 patients (31%) had no neurological deficits, 22 patients (34%) had minor deficits that did not interfere with their daily life activities, and 23 patients (35%) had moderate or severe deficits such as severe ataxia, spastic paresis, seriously reduced vision, or epilepsy with more than two seizures per year. Fourteen of the 31 patients (45%) registered with ataxia preoperatively had recovered fully. Six of seven patients had persistence of a pre- or postoperatively developed hemiparesis. Thirteen of 23 patients had persistence of cranial nerve deficits that developed second to surgery. Fifty-five percent of the 18 patients with seizures at diagnosis were seizure-free at follow-up. At follow-up both ataxia and hemiparesis were significantly more frequent among females (P =.02 and P =.03, respectively). CONCLUSION: In patients who received operation as the only treatment for their brain tumor, there was a good chance of total or partial recovery of preoperative and postoperative neurological deficits, although only one third of the patients will have no long-term neurological deficits.  相似文献   
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Background To our best knowledge, Panton–Valentine leucocidin (PVL)-positive methicillin-sensitive Staphylococcus aureus (MSSA) has not been described yet as cause for severe pyomyositis. Case report We present a 23-year-old apparently healthy male patient without any typical predisposing findings who developed severe pyomyositis secondary to an operated pilonidal cyst. In the follow-up, the patient showed signs of immunocompromisation. The causative agent for purulent infection of multiple muscles was a MSSA strain harbouring PVL toxin. Results In the reported case, aggressive antibiotic and surgical treatment with additional application of immunoglobulins has lead to recovery from the disease without relapse. Conclusions PVL-positive S. aureus are associated with skin diseases, multiple abscesses and often complicated by severe sepsis and necrotising pneumonia. Under such circumstances, the mortality rate can reach up to 75%. In addition, the PVL toxin can cause immunocompromisation and might be therefore involved in the aetiology of pyomyositis. Aggressive antibiotic and surgical treatment with additional application of immunoglobulins is recommended for treatment.  相似文献   
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BACKGROUND AND OBJECTIVES: An eight-member group consisting of Canadian infectious disease and immunology specialists and a family physician with significant experience in HIV management was convened to update existing recommendations, specifically intended for use by Canadian HIV-treating physicians, on the appropriate use of enfuvirtide in HIV/AIDS patients with resistance to other antiretroviral drugs. METHODS: Evidence from the literature and expert opinions of the group members formed the basis of the guidelines. Comments on the draft guidelines were obtained from other physicians across Canada with HIV expertise. The final guidelines represent the group's consensus agreement. RESULTS AND CONCLUSIONS: The recommendations were developed to guide physicians in optimal practices in patient selection for enfuvirtide treatment and subsequent patient management. The issues considered include positive predictors of response to enfuvirtide, stage of disease, optimization of the background regimen, early indicators of enfuvirtide response, and patient education and support.  相似文献   
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BACKGROUND: Early environment is a major determinant of long-term mental health, evidenced by the relationship between early-life neglect or abuse and chronically increased vulnerability to developmental psychopathology, including major depressive disorder (MDD). Animal studies can increase understanding of environmentally mediated causal risk processes. We describe how daily deprivation of biological parenting in primate infants disrupts development of homeostatic and reward systems central to MDD. METHODS: Nine breeding pairs of marmoset monkeys provided control twins (CON) and early-deprived twins (ED); the latter were socially isolated for 30-120 min/day on days 2-28. During the first year of life, basal urinary norepinephrine (NE) titers and cardiophysiologic activity were measured. At the end of year 1 (adolescence), automated neuropsychologic tests were conducted to measure responsiveness to changes in stimulus-reward association (simple/reversed visual discrimination learning) and to reward per se (progressive ratio [PR] reinforcement schedule). RESULTS: The ED monkeys exhibited increased basal urinary NE titers and increased systolic blood pressure relative to CON siblings. The ED monkeys required more sessions to reinstate stimulus-oriented behavior following reversal, suggesting increased vulnerability to perceived loss of environmental control; ED monkeys also performed less PR operant responses, indicating that reward was less of an incentive and that they were mildly anhedonic relative to CON. CONCLUSIONS: In marmoset monkeys, neglect-like manipulation of ED leads to chronic changes in homeostatic systems, similar to those in children and adolescents exposed to early-life adversity and in MDD, and to responses to environmental stimuli similar to those that characterize MDD.  相似文献   
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Relief of symptoms for patients and families throughout the illness trajectory requires that palliative care practitioners have knowledge and skill, both in assessment and use of pharmacologic and complementary therapies. This article presents the didactic content of symptom assessment and management, and the experiential experiences used in a nondrug laboratory within the End-of-Life Nursing Education Consortium (ELNEC) curriculum.  相似文献   
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BACKGROUND: Somatisation is highly prevalent in primary care (present in 25% of visiting patients) but often goes unrecognised. Non-recognition may lead to ineffective treatment, risk of iatrogenic harm, and excessive use of healthcare services. AIM: To examine the effect of training on diagnosis of somatisation in routine clinical practice by general practitioners (GPs). DESIGN OF STUDY: Cluster randomised controlled trial, with practices as the randomisation unit. SETTING: Twenty-seven general practices (with a total of 43 GPs) in Vejle County, Denmark. METHOD: Intervention consisted of a multifaceted training programme (the TERM [The Extended Reattribution and Management] model). Patients were enrolled consecutively over a period of 13 working days. Psychiatric morbidity was assessed by means of a screening questionnaire. GPs categorised their diagnoses in another questionnaire. The primary outcome was GP diagnosis of somatisation and agreement with the screening questionnaire. RESULTS: GPs diagnosed somatisation less frequently than had previously been observed, but there was substantial variation between GPs. The difference between groups in the number of diagnoses of somatisation failed to reach the 5% significance (P = 0.094). However, the rate of diagnoses of medically unexplained physical symptoms was twice as high in the intervention group as in the control group (7.7% and 3.9%, respectively, P = 0.007). Examination of the agreement between GPs' diagnoses and the screening questionnaire revealed no significant difference between groups. CONCLUSION: Brief training increased GPs' awareness of medically unexplained physical symptoms. Diagnostic accuracy according to a screening questionnaire remained unaffected but was difficult to evaluate, as there is no agreement on a gold standard for somatisation in general practice.  相似文献   
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