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51.
Diffusion tensor magnetic resonance imaging (DTI) provides data concerning water diffusion in the spinal cord, from which white matter tracts may be inferred, and connectivity between spinal cord segments may be determined. We evaluated this potential application by imaging spinal cords from normal adult rats and rats that received cervical lateral funiculotomies, disrupting the rubrospinal tract (RST). Vitrogen and fibroblasts were transplanted into the surgical lesion at time of injury in order to fill the cavity. At 10 weeks, animals were sacrificed; the spinal cords were dissected out and then imaged in a 9.4-Tesla magnet. DTI tractography demonstrated the disruption of the rubrospinal tract axons while indicating which axon tracts were preserved. Additionally, DTI imaging could identify the orientation of glial processes in the gray matter adjacent to the site of injury. In the injured animals, reactive astrocytes in adjacent gray matter appeared to orient themselves perpendicular to white matter tracts. In summary, DTI identified not only white matter disruption following injury, but could distinguish the orientation of the accompanying glial scar.  相似文献   
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We report a 33‐year‐old female with cutaneous involvement by Churg‐Strauss syndrome confined to surgical scars that were obtained 13 years before. She presented to the emergency department with 2‐day history of fever, night sweats, right‐sided weakness, hoarseness and worsening asthma symptoms. She was found to have an eosinophilia and two sub‐5‐mm pulmonary nodules. The patient also reported that the scars on her right thumb, inner wrist and back had been swollen, red and painful for 2 days. Examination revealed tender, erythematous, well‐healed edematous scars studded with small skin colored papules. She had no clinical findings that were classic for cutaneous vasculitis. A skin biopsy of a scar revealed perivascular and palisading granulomatous inflammation consisting of histiocytes and neutrophils with leukocytoclasia. Focal vascular injury was identified. Scattered tissue eosinophils were seen. Special stains were negative for infection. Thereafter, she was started on intravenous steroids, at which point the fever, pulmonary and cutaneous symptoms subsided. Although scar sarcoidosis is a well‐described phenomenon, granulomatous inflammation and vasculitis seen in Churg‐Strauss syndrome exclusively manifesting in well‐healed surgical scars highlights the unique features seen in this case and draws attention to the concept of locus minoris resistentiae. This case also highlights how a skin biopsy in the setting of suspected systemic vasculitis can confirm the presence of vasculitis and/or granulomatous inflammation and obviate the need for more invasive, higher risk procedures such as lung biopsy.  相似文献   
53.
McCaul LK 《Dental update》2012,39(2):135-8, 140
The incidence of head and neck cancer is rising. The attendant oral complications of cancer management make oral health maintenance a lifelong challenge for these patients. Holistic management in the context of a core multidisciplinary team is essential in optimizing outcomes. Predicting the risk of adverse oral outcomes is difficult. Effective communication between healthcare professionals in the core and extended teams and with the patient is essential. CLINICAL RELEVANCE: Primary care dental teams will be involved in the long-term management of oral care for head and cancer patients. A broad understanding of the management of head and neck cancer, consequences of treatment and the need for good communication is key to good quality patient care.  相似文献   
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The results of treatment of 629 previously untreated adults with acute leukemia at Memorial Hospital are reviewed. During the past 14 years, 135 adults (greater than 15 years) with acute lymphoblastic leukemia (ALL) have been treated with one of three successive multidrug-intensive treatment protocols (L2, L10/10M, and L17/17M), each calling for 2.5 to 3 years of systemic chemotherapy and prophylactic intrathecal methotrexate without cranial irradiation. The complete remission (CR) rates were L2 (n = 22) = 77%; L10/10M (n = 69) = 86%; L17/17M (n = 44) = 77%. The median durations of survival and remission were, respectively, L2 = 33 and 30 months; L10/10M = 62 months and not reached; and L17/17M = not reached. Almost all relapses occurred within the first 3 years while still continuing treatment, and there were only rate late relapses after stopping treatment. It appears that approximately half of the patients may have been cured with the latest two protocols. During the last 17 years, 494 adults aged 15 to greater than 70 with acute nonlymphoblastic leukemia (ANLL) were treated with one of five successive multiple drug treatment protocols of varying intensity (arabinosylcytosine + 6-thioguanine [n = 36]; L6 [n = 101]; L12 [n = 104]; L14/14M [n = 121]; and L16/16M [n = 132]). Patients with myelodysplastic syndromes generally were not treated until they developed acute leukemia, but were then entered and included in the results. Secondary leukemias following treatment of other neoplastic diseases were not included. The complete remission rates were fairly constant between 47 and 64% and the median durations of remissions were between 9 and 21 months. The intensive treatment L14 and L16 protocols were associated with more early deaths and did not result in a significantly improved remission incidence or duration or survival. With all protocols, the majority of relapses occurred within the first 2 years, but relapses continued to occur at a decreasing rate for 4 years and occasionally even later. Whereas a small fraction (approximately 10 to 15%) of adults with ANLL are now apparently being cured with combination chemotherapy, despite intensive efforts there has been little improvement during the last decade and more selective and effective forms of treatment are urgently needed.  相似文献   
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Specific binding of the agonist, 3H-epinephrine, and antagonist, 3H-prazosin, to alpha 1-adrenergic receptors in both intact and broken rat parotid cell preparations was measured as a function of age in Wistar rats. Agonist binding exhibited approximately tenfold weaker affinity (Kd approximately 10 nM) for both intact and broken cells than did the antagonist (Kd approximately 1 nM). In addition, Bmax for the agonist was only 25 to 50% of that of the antagonist (7-10 fmol/mg protein vs. 15-30 fmol/mg protein) in both preparations. Binding affinity decreased significantly between ages 3 and 24 months for the antagonist but not the agonist in both intact and broken cells. The number of binding sites did not change with age in intact cells when measured with either agonist or antagonist, or when measured with agonist in broken cells, but increased markedly (approximately two fold) with age in broken cells for the antagonist. The latter results support the hypothesis that the aged rat parotid cell exhibits a naturally occurring, post-alpha 1-adrenoreceptor defect in signal transduction.  相似文献   
59.
To investigate the role of neutrophils in complement-induced changes in vascular permeability, skin wheal and flare responses to intradermal injection of autologous activated serum complement were measured in normal and neutropenic subjects. In normal subjects, responses were dose-dependent and were abolished by removal of C5 from serum. Biopsy of a wheal revealed neutrophils adherent to vascular endothelium. In neutropenic subjects (neutrophil count less than 0.5 X 10(9)/l), responses to complement-activated serum or a low molecular weight fraction from it were significantly reduced. This could not be accounted for by a reduction in concentration of C5 conversion products. In one subject with chronic granulomatous disease a normal response was produced. Local injection of the anti-histamine (H1) drug clemastine produced only partial inhibition of responses, while almost totally abolishing histamine-induced wheals. Systemic anti-inflammatory drugs had no effect. The data suggest that the microvascular response to activated complement in man is at least partly due to an interaction between C5 fragments and neutrophils.  相似文献   
60.
The non-synonymous mutations arg16gly (rs1042713) and gln27glu (rs1042714) in the adrenergic β-2 receptor gene (ADRB2) have been associated with cognitive function and brain white matter integrity. The current study aimed to replicate these findings and expand them to a broader range of cognitive and brain phenotypes. The sample used is a community-dwelling group of older people, the Lothian Birth Cohort 1936. They had been assessed cognitively at age 11 years, and undertook further cognitive assessments and brain diffusion MRI tractography in older age. The sample size range for cognitive function variables was N = 686–765, and for neuroimaging variables was N = 488–587. Previously-reported findings with these genetic variants did not replicate in this cohort. Novel, nominally significant associations were observed; notably, the integrity of the left arcuate fasciculus mediated the association between rs1042714 and the Digit Symbol Coding test of information processing speed. No significant associations of cognitive and brain phenotypes with ADRB2 variants survived correction for false discovery rate. Previous findings may therefore have been subject to type 1 error. Further study into links between ADRB2, cognitive function and brain white matter integrity is required.  相似文献   
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