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71.
Dennis M Edelstein K Copeland K Frederick JA Francis DJ Hetherington R Blaser SE Kramer LA Drake JM Brandt ME Fletcher JM 《Neuropsychology》2005,19(4):456-465
Inhibition of return (IOR) refers to an increase in time to react to a target in a previously attended location. Children with spina bifida meningomyelocele (SBM) and hydrocephalus have congenital dysmorphology of the midbrain, a brain region associated with the control of covert orienting in general and with IOR in particular. The authors studied exogenously cued covert orienting in 8- to 19-year-old children and adolescents (84 with SBM and 37 age-matched, typically developing controls). The exogenous cue was a luminance change in a peripheral box that was 50% valid for the upcoming target location. Compared with controls, children with SBM showed attenuated IOR in the vertical plane, a deficit that was associated with midbrain dysmorphology in the form of tectal beaking but not with posterior brain volume loss. The data add to the emerging evidence for SBM deficits in attentional orienting to salient information. 相似文献
72.
A study was performed to investigate the effectiveness of hydroxyapatite cement (HAC) as a new carrier system in the treatment of chronic, posttraumatic osteomyelitis. In the in vitro study, release of gentamicin from standard cylinders of HAC were measured by agar diffusion test. As a representative for mechanical properties, compression strength was measured in order to detect changes when mixing HAC with gentamicin. In the in vivo study, bone infection was induced according to the model of Norden by injection of 1 ml Na-morrhuat and 3 x 10(6)CFU Staphylococcus aureus. After 3 weeks, when chronic stage of infection was obtained, 17 animals were treated by debridement and filling the marrow either with HAC alone or HAC mixed with gentamicin (32 mg/g). Animals of the control groups were left untreated. After 6 weeks, all animals were sacrificed. Hematological, radiological, microbiological and histological examinations were carried out by covered investigation. Best evidence of the efficiency of treatment was observed in histopathological and microbiological findings. In all swabs of the control groups, taken 6 weeks following infection S. aureus were detected which were clonal to the strain used for induction of osteomyelitis. In HAC/gentamicin-treated animals, no growth was detectable after 7 days of culturing in BHI bouillon. In the HAC/gentamicin-treated group, there was no histopathological evidence of infection. In all other groups different stages of chronic osteomyelitis were found. No side effect was observed, neither locally nor systemically by HAC or gentamicin. Therefore, HAC is considered to be a very effective carrier for antibiotics in treatment of chronic, posttraumatic osteomyelitis. 相似文献
73.
Zusammenfassung Durch quantitative Bestimmung des Abbaus kompatibler fetaler Erythrocyten, die bei fetomaternalen Transfusionen in den Kreislauf der Mutter eingeschwemmt waren, wird die verkürzte Überlebenszeit von Erythrocyten Neugeborener bestätigt. Aus den Befunden geht weiter hervor, daß der Nachweis fetomaternaler Transfusionen als Ursache für Neugeborenenanämien auch noch 4–6 Wochen nach der Geburt erfolgen kann, wenn die kindlichen Erythrocyten für die Mutter kompatibel sind.Mit teilweiser Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
74.
Comparison of disseminated and nondisseminated strains of Borrelia burgdorferi sensu stricto in mice naturally infected by tick bite 下载免费PDF全文
Dolan MC Piesman J Schneider BS Schriefer M Brandt K Zeidner NS 《Infection and immunity》2004,72(9):5262-5266
Clinical isolates of Borrelia burgdorferi sensu stricto have been categorized into disseminated and nondisseminated groups based on distinct ribosomal spacer restriction fragment length polymorphism genotypes (RSTs). In order to determine whether transmission by tick bite would alter the dissemination dynamics and disease produced by distinct genotypes, disseminated isolates (RST1), nondisseminated isolates (RST3), and a standard laboratory strain (B-31) were established in a murine cycle utilizing infections transmitted by ticks. B-31 spirochetes circulated in the blood of inbred C3H/HeJ mice longer than in the blood of outbred mice. The majority of C3H mice exposed to RST1-infected ticks contained cultivable spirochetes in their blood for up to 17 days; in contrast, mice exposed to RST3 isolates demonstrated a precipitous decline in infection after day 7 postexposure. A quantitative PCR (q-PCR) assay demonstrated that the densities of spirochetes in blood were similar for the RST1 and RST3 isolates, except during the 2nd week postexposure, when the RST1 isolates displayed a markedly higher density in blood. Spirochete load in the heart and bladder of infected mice was measured by q-PCR at 8 weeks postexposure; the numbers of spirochetes in these tissues were similar for mice infected with either disseminated or nondisseminated strains. Similarly, histopathology samples of heart, bladder, and joint tissue obtained at 8 weeks postexposure did not reveal greater pathology in mice infected with the disseminated isolates. We conclude that although the spirochetemia induced by tick-transmitted disseminated isolates was more intense and of longer duration than that induced by nondisseminated isolates, the resultant pathologies produced by these strains were ultimately similar. 相似文献
75.
Encephalitis is a rare, but serious complication from vaccination against smallpox using replication competent strains of vaccinia virus. In this report we describe mutants of vaccinia virus, containing N-terminal deletions of the vaccinia virus interferon resistance gene, E3L, that are attenuated for neuropathogenesis in a mouse model system. These recombinant viruses replicated to high titers in the nasal mucosa after intra-nasal infection of C57BL/6 mice but failed to spread to the lungs or brain. These viruses demonstrated reduced pathogenicity after intra-cranial infection as well, indicating a decrease in neurovirulence. Intra-nasal inoculation or inoculation by scarification with a low dose of recombinant virus containing a deletion of the entire N-terminal domain of E3L protected against challenge with a high dose of wild-type vaccinia virus, suggesting that this replication competent, but attenuated strain of vaccinia virus may have promise as an improved vaccine for protecting against smallpox, and as a vector for inducing mucosal immunity to heterologous pathogenic organisms. 相似文献
76.
Herpes simplex burn wound infections: epidemiology of a case cluster and responses to acyclovir therapy 总被引:1,自引:0,他引:1
Nosocomial transmission of herpes simplex virus (HSV) has been described in intensive care units. A cluster of three patients with HSV wound infections within a 6-week period prompted temporary closure of a burn unit and suggested nosocomial cross infection. However, restriction endonuclease "fingerprint" analysis of the HSV isolates showed them to be genetically and therefore epidemiologically unrelated. This report describes these cases and the use of intravenous acyclovir in the treatment of HSV burn wound infections. 相似文献
77.
Finn Jung Katharina Burger Raphaela Staltner Annette Brandt Sebastian Mueller Ina Bergheim 《Nutrients》2021,13(5)
Changes in intestinal microbiome and barrier function are critical in the development of alcohol-related liver disease (ALD). Here, we determined the effects of a one-week alcohol withdrawal on parameters of intestinal barrier function in heavy drinkers with ALD in comparison to healthy non-drinkers (controls). In serum samples of 17 controls (m = 10/f = 7) and 37 age-matched ALD patients (m = 26/f = 11) undergoing a one-week alcohol withdrawal, markers of liver health and intestinal barrier function were assessed. Liver damage, e.g., fibrosis and hepatic steatosis, were assessed using FibroScan. Before alcohol withdrawal, markers of liver damage, lipopolysaccharide binding protein (LBP) and overall TLR4/TLR2 ligands in serum were significantly higher in ALD patients than in controls, whereas intestinal fatty acid binding protein (I-FABP) and zonulin protein concentrations in serum were lower. All parameters, with the exception of LBP, were significantly improved after alcohol withdrawal; however, not to the level of controls. Our data suggest that one-week of abstinence improves markers of intestinal barrier function and liver health in ALD patients. 相似文献
78.
Fatima Sheikh Nicole Brandt Dominique Vinh Rebecca D. Elon 《Journal of the American Medical Directors Association》2021,22(6):1199-1205
Despite the dynamic demands in the nursing home (NH), a definitive approach to managing chronic pain in older adults has yet to be established. Due to concerns for potential adverse pharmacologic effects, balancing appropriate pain management is a challenge among NH residents. The challenges encompass but are not limited to medical complexities, functional disabilities, and physical frailty. Barriers to the successful implementation of a comprehensive chronic pain management at the NH may include ambiguous directions on specific therapeutic interventions, insufficient guidance on treatment duration, and limited available treatment options. The Centers for Medicare and Medicaid Services’ reporting requirement of adequate pain control among NH residents coupled with widely variable clinician-prescribing habits highlights the difficulties in overcoming the preceding challenges and barriers. The Coronavirus Disease 2019 (COVID-19) pandemic has further complicated pain management due to its negative consequences on well-being of residents of NHs. Associated symptoms of psychosocial stress, anxiety and depression, and chronic pain symptoms can exacerbate during the COVID-19 pandemic, leading to increased requirement for pain medications including but not limited to opioids.Pain is a multidimensional symptom and requires a strategic multimodal approach for its management. Nonpharmacologic modalities are underutilized in the NH setting and are the preferred first steps for mild pain, and nonopioid pharmacological agents can be added as a second step for a synergistic effect for moderate to severe pain. Opioids should be used as a last resort. Short-acting opioids are preferred over extended-release/long-acting opioids for chronic pain. Clinicians are encouraged to engage residents in proactive strategies in managing their pain, and to set realistic expectations toward improving their quality of life, as complete elimination of pain is not feasible in most cases.This review article provides the interdisciplinary team with a contemporary perspective of the multitude of changes and challenges influencing the prescribing as well as deprescribing of various pain medications. 相似文献
79.
80.
Birgitte Hertz Carsten A. Brandt Michael B. Petersen Søren Pedersen Ulrich König Helle Strømkjær Peter K. A. Jensen 《Clinical genetics》1993,44(2):89-94
Hertz B, Brandt CA, Petersen MB, Pedersen S, König U, Strømkjær H, Jensen PKA. Application of molecular and cytogenetic techniques to the detection of a de novo unbalanced t(11q;21q) in a patient previously diagnosed as having monosomy 21.
Clin Genet 1993: 44: 89–94. © Munksgaard, 1993
The occurrence of complete autosomal monosomy in man is extremely rare and generally considered to be incompatible with life. Since the introduction of banding techniques in human cytogenetics, several cases of presumptive monosomy for chromosome 21 have nevertheless been reported. However, it has been suggested that most, if not all, of these cases may represent unbalanced translocations or other structural aberrations resulting in only partial monosomy 21. Here we describe a patient in whom full monosomy 21 was initially diagnosed by routine karyotyping. Re-examination with a combination of high resolution banding technique, chromosome painting and DNA polymorphism analysis demonstrated the presence of an unbalanced translocation between the long arms of chromosome 11 and 21, respectively. Consequently, the case was re-classified as a partial monosomy for the proximal long arm of chromosome 21. 相似文献
Clin Genet 1993: 44: 89–94. © Munksgaard, 1993
The occurrence of complete autosomal monosomy in man is extremely rare and generally considered to be incompatible with life. Since the introduction of banding techniques in human cytogenetics, several cases of presumptive monosomy for chromosome 21 have nevertheless been reported. However, it has been suggested that most, if not all, of these cases may represent unbalanced translocations or other structural aberrations resulting in only partial monosomy 21. Here we describe a patient in whom full monosomy 21 was initially diagnosed by routine karyotyping. Re-examination with a combination of high resolution banding technique, chromosome painting and DNA polymorphism analysis demonstrated the presence of an unbalanced translocation between the long arms of chromosome 11 and 21, respectively. Consequently, the case was re-classified as a partial monosomy for the proximal long arm of chromosome 21. 相似文献