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Meningitis     
The most frequent pathogens causing bacterial meningitis in Germany are Neisseria meningitidis, Streptococcus pneumoniae, Borrelia burgdorferi, Listeria monocytogenes and staphylococci. Since immunization against Haemophilus influenzae has become a routine vaccination procedure, this pathogen no longer plays a significant role in the etiology of bacterial meningitis. A number of pilot studies have indicated that selected PCR methods most probably represent the future etiological diagnosis of bacterial meningitis. The easiest and most rapid diagnostic method is, however, still a simple gram stain preparation. In fatal cases that ran a peracute course, especially in the Waterhouse-Friderichsen syndrome, only increased congestion of the surface of the brain is detectable at autopsy. In such cases, there is hardly any histological evidence of an inflammatory reaction of the leptomeninges. In cases of purulent meningitis, in addition to the typical infiltration of the subarachnoid space with abundant granulocytes, after some days of illness there is a wide-spread histomorphological picture of pathological alterations with fibrinoid vessel wall necroses, thromboses, ventriculitis, infarctions as well as venous and arterial vasculitis. The breakdown of the integrity of the blood-brain-barrier in bacterial meningitis is obviously due to a separation of intercellular tight junctions of the endothelium of the capillaries of the leptomeninges. The cause of death in meningitis, depending on the severity and duration of a concomitant sepsis, is an increase in intracranial pressure that leads to a circulus vitiosus (via a reduced central perfusion associated with metabolic acidosis) with cerebral vasodilatation. This is followed by an additional rise of intracranial pressure and finally a reduced cerebral blood supply and central dysregulation. The medico-legal expert is occasionally confronted with this topic against the background of a possible misjudgement of the disease due to insufficient diagnostics or delayed diagnosis and in the light of a posttraumatic or nosocomial origin of the illness.  相似文献   
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This commentary discusses the need for, and the advantages of, a more concise, revised definition of the field of health services research. It argues for a definition that includes not only the topics on which health services research focuses but also the goals of health services research. A number of condensed definitions are provided for consideration.  相似文献   
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OBJECTIVE: The authors examined the accuracy of certain neuropsychological tests in the prediction of harm resulting from self-neglect in cognitively impaired seniors who lived alone. METHODS: The study included 130 participants, aged 65 and older, who scored less than 131 on the Dementia Rating Scale. Neuropsychological tests were administered at baseline, resulting in eight predictive scores. Informants and primary care physicians provided information about harm that occurred to the participants during the 18-month prospective follow up. An incident was defined as harmful if it occurred as the result of self-neglect or disorientation and resulted in physical injury or property loss or damage and required emergency interventions. Proportional hazard regression analysis was conducted to examine the predictive relationship between the eight neuropsychological tests and time to incident harm with age, sex, education, the Charlson Comorbidity Index, and the Mini-Mental State Examination included in the model as covariates. RESULTS: Twenty-seven participants experienced harm during the 18-month follow-up period. A proportional hazards model indicated that three neuropsychological tests, which measured recognition memory, executive functioning, and conceptualization, were independent risk factors for harm. CONCLUSIONS: These findings provide insight into why harm occurred in these cognitively impaired elders who lived alone. They also support the ecologic validity of these tests and suggest directions for the development of intervention strategies for harm prevention.  相似文献   
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About 3–4% of all tumors and tumor-like lesions of the skeleton are located in the foot. Many of these lesions have a predilection for certain locations, so that the spectrum of entities occurring in the foot differs from the rest of the skeleton. Despite the fact that practically any entity can occur in the foot in rare cases, taken together the ten most frequent lesions make up for the vast majority of tumors and tumor-like lesions of the foot. The differential diagnosis of these lesions follows the general principles that apply in the rest of the skeleton. It is based on the analysis of the lesion’s X-ray morphology and location, the patient’s age, and in certain entities, the MR morphology. This article describes the most important tumors and tumor-like lesions of the foot, their differential diagnosis, and the principles of local staging.  相似文献   
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Rupture of the Achilles tendon is typically associated with sportive activities with increasing tendency; it occurs most commonly in the third to fourth decade of life with a male-to-female ratio of 5–10:1. Ruptures are caused predominantly by a sudden, unexpected overextension of the tendon while direct trauma is less frequent. The recommended treatment of the injury remains controversial. In Germany, due to the good functional results, the open surgical repair represents the standard therapy since many years. The open suture technique offers the advantage of a lower re-rupture rate but is associated with the risk of wound-related complications including infection. By percutaneous suture techniques a significant decrease in the rate of infections and complications in wound healing could be achieved by minimal-access with reduced soft tissue trauma; on the other hand an increased rate of lesions of the sural nerve is reported. Dynamic imaging assessment of ultrasound or MRI allows a more accurate localisation of the ruptured ends of the tendons which is the prerequisite for the non-operative primary functional treatment of Achilles tendon ruptures. This conservative treatment regime is recommended when adaptation of the ends of the ruptured tendon is possible in 20° plantar flexion of the foot. Moreover, the desired level of daily activity and the patients’ degree of compliance has to be considered. Operative management should be avoided in the elderly patient or patients with risk factors like immunosuppressive therapy, diabetes mellitus, steroid use or failure to comply.  相似文献   
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Despite evidence from previous unit recording, microstimulation, lesioning and anatomical studies, the functions of the midbrain periaqueductal gray (PAG) remain unclear. We attempted to clarify the function of the PAG by recording activity of PAG units along with laryngeal and respiratory electromyograms (EMG) during vocalization in awake monkeys. PAG units were classified with respect to vocalization on the basis of their discharge patterns as 'early burst', 'late burst', 'tonic-increase' and 'tonic-off', with the vast majority being of the early- and late-burst type. Early-burst cells were correlated most frequently with inspiratory muscles of the respiratory system and laryngeal abductor muscles. Late-burst cells were most clearly correlated with laryngeal adductor and expiratory respiratory muscles. Data from spike-triggered averaging and parametric correlations indicate that most cells are related to single muscles, but a significant number were related to functionally related groups of two or more muscles. The results suggest that the PAG determines qualitative aspects of vocalization by the multisynaptic action its cells have on laryngeal and respiratory motoneurons.  相似文献   
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