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Background The role of the vagal nerve in the autonomic nervous system is widely well known. Recently, an additional function was revealed serving as a connector between the nervous and immune system. This connection is called the “cholinergic inflammatory pathway.” Through stimulation of the acetylcholine receptors located upon the macrophages, the “unspecific” immune system can be directly influenced. Methods The vagal nerve was completely transected directly posterior to its passage through the diaphragm. The effect of complete vagotomy was analyzed using a murine model of polymicrobial peritonitis (colon ascendens stent peritonitis, CASP). Survival and clinical course of vagotomized or sham-operated mice were analyzed in the CASP model. Results After CASP surgery, vagotomy led to a significantly increased mortality (64.7%) in comparison to sham-vagotomized animals (34%). No difference in the bacterial load of various tissues (lung, liver, spleen, blood, lavage fluid, and kidney) from septic animals with or without vagotomy was observed. Vagotomized animals reveal elevated serum cytokine levels (TNF, IL-6, IL-10, and MCP-1) 20 h after the induction of polymicrobial peritonitis. Conclusion The vagal nerve is therefore an important modulator of the immune system. W. Kessler and T. Traeger contributed equally to this work Best of Forum Papers presented at the Annual Meeting of the German Society of Surgery, 2–5 May 2006, Berlin, Germany  相似文献   
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Summary Meiotic fine-structure maps of two efficient UGA suppressors of Schizosaccharomyces pombe which are known (sup8-e) or inferred (sup10-e) to code for two leucine tRNAs carrying the mutant anticodon U*CA (Kohli et al. 1979, 1980a, b; Wetzel et al. 1979; Mao et al. 1981) are presented. In both cases, the recombination frequencies given by the primary site of the anticodon mutation fitwell into the map defined by the sites of a number of inactivating secondary mutations. This contrasts the corresponding situation found in the serine tRNA genes sup3 and sup9 where the anticodon site exhibits a specific marker effect which strongly increases recombination frequencies in crosses with all revertant sites, due to a decrease in the efficiency of excision repair of base-pair mismatches whenever the anticodon site is included in hybrid-DNA (Hofer et al. 1979; Munz and Leupold 1979; Thuriaux et al. 1980). A pronounced specific marker effect which leads to a several fold increase of the recombination frequencies over those expected is observed, however, at one of the secondary inactivating sites mapping in the leucine tRNA gene sup8.  相似文献   
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To determine the sensitivity and specificity of the periodic acid-Schiff (PAS) stain in the diagnosis of acute leukemia in light of the finer characterization of this disorder now available through immunophenotyping, we examined the blasts from 51 patients with newly diagnosed acute leukemia by morphological, cytochemical, and immunophenotypic analyses. The 51 patients represented every new case of acute leukemia subjected to cytochemical stains and flow cytometry between July 1987 and February 1989. By cell-surface marker analysis, 29 exhibited lymphocytic lineage, while 21 were myelocytic. One was mixed lineage. The PAS positivity, defined by the presence of blocks or coarse granules in 5% or more of the blasts, was found in 15 of 29 lymphoblastic leukemias and in four of the myeloblastic leukemias. However, PAS-positive lymphoblastic leukemias were negative with the other cytochemical stains: myeloperoxidase, Sudan black B, and alpha-naphthyl butyrate esterase. The PAS-positive myeloblastic leukemias were positive with at least one other stain. Three cases of myeloblastic leukemia exhibited greater than 10% PAS-positive blasts, with all three being acute monoblastic leukemia. Thus, the sensitivity and specificity of the PAS stain alone for lymphoblastic leukemia was 52% (15 true positives of 29) and 81% (four false positives), respectively. The sensitivity of a cytochemical-staining combination of PAS positivity and myeloperoxidase, Sudan black B, and alpha-naphthyl butyrate esterase negativity in defining cases of lymphoblastic leukemia remained at 52%; however, the specificity of this combination for lymphoblastic leukemia was 100% (no false positives). Thus, a positive PAS stain, in combination with negative myeloperoxidase, Sudan black B, and alpha-naphthyl butyrate esterase stains, continues to have a diagnostic role in the distinction between lymphoblastic and myeloblastic leukemia, and greater immunologic sophistication serves to support this position.  相似文献   
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Die Sentinel-Lymphknotenbiopsie (Sentinel-Node-Biopsie, SNB) ist ein diagnostisches Verfahren beim Mammakarzinom, mit dem der Nodalstatus durch selektive Entnahme und Untersuchung des (der) Lymphknoten mit der höchsten Wahrscheinlichkeit für eine Metastasierung bestimmt wird. Hauptziel der Methode ist eine vollständige Erfassung der Patientinnen mit Lymphknotenmetastasen sowie die Vermeidung von Morbidität durch eine Axilladissektion bei nodalnegativen Frauen. Aufgrund der hohen Übereinstimmung zwischen dem histologischem Status des Sentinel-Nodes und dem definitiven Nodalstatus (ermittelt durch konventionelle Axilladissektion) stellt sich immer mehr die Frage, ob und unter welchen Bedingungen die SNB als Routineverfahren für das axilläre Staging gelten kann.  相似文献   
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Previous research has emphasized facets of both the organizational environment and individual differences as predictors of work engagement. This study explored sleep hygiene as another important behavioural factor that may be related to work engagement. With a sample of 328 adult workers, we tested a multiple mediator model in which sleep hygiene predicts work engagement through one's appraisals of resource depletion stemming from demands (psychological strain) and general self‐regulatory capacity (self‐control). Results indicated that individuals who frequently engaged in poor sleep hygiene behaviours had lower self‐regulatory capacity, experienced higher subjective depletion and were less engaged at work. Additionally, the path from poor sleep hygiene to decreased work engagement was attributed to perceptions of personal resources that are needed to exert self‐regulatory energy at work. This is consistent with current self‐regulatory theories suggesting that individuals have a limited amount of resources to allocate to demands and that the depletion of these resources can lead to stress and lower self‐regulatory functioning in response to other demands. Specifically, poor sleep hygiene results in the loss of self‐regulatory resources needed to be engaged in work tasks by impairing the after‐work recovery process. Practical and research implications regarding sleep hygiene interventions for well‐being and productivity improvement are discussed. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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This reflection describes a life‐limiting case of oral squamous cell carcinoma (SCC) that required thoughtful management facilitated by an advance care plan (ACP). A 70‐year‐old female was diagnosed with a T4aN2bM0 biopsy‐proven invasive, well‐differentiated keratinizing SCC. Surgical wide‐local excision included teeth #11‐16 with left unilateral neck dissection, levels I‐V. She was rehabilitated with maxillary obturator prosthesis and underwent chemoradiation therapy. Her course was complicated by dysphagia and trismus. She experienced multiple recurrences. At a certain point, negative margins could not be achieved without facial disfigurement. The patient, her husband, and providers decided together that further management would be palliative. Before the additional surgical procedures, she communicated a thorough ACP with her husband and providers who were prepared to facilitate difficult care decisions on her behalf. The patient passed away at home with hospice care at the age of 74. This motivated patient with oral SCC and impactful postmanagement complications appreciated the clarity of an ACP. Her values and goals of care were incorporated with ongoing communication and documentation of this plan, which was instrumental in facilitating her person‐centered care. The providers apply lessons learned here in future practice and education of residents and students.  相似文献   
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The methods and the radioisotopes used in scintiscanning of the liver have recently seen major advances. The clinical indications for scintigraphy in focal and diffuse diseases of the liver are discussed. Scintigraphy compares favorably with other imaging techniques with regard to sensitivity and specificity.  相似文献   
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Medication-related osteonecrosis of the jaw (MRONJ) is a severe side effect of antiresorptive (AR) drugs such as bisphosphonates (BP) and denosumab (Dmab). Although several risk factors are described, the etiology of MRONJ is still not fully elucidated. Bone-strengthening is the primary aim of antiresorptive therapy; however, overly increased bone mass and microcrack accumulation are also discussed in MRONJ etiologies. The aim of this study is to evaluate the microarchitecture of jaw bones with micro?computed tomography (micro-CT) in AR-treated patients with or without MRONJ.Human jaw bone samples of AR-treated patients were separated into 11 groups by AR treatment bisphosphonate (BP), denosumab (Dmab), both (M) and control groups. Subgroups were divided according to the clinical localization as AR-exposed vital jaw bone (BPexp, Dmabexp, Mexp), osteonecrosis–margin of a sequestrum (BPOmar, DmabOmar, MOmar) and osteonecrosis–sequestrum (BPOseq, DmabOseq, MOseq). Healthy jaw bone (CHB) and osteoporotic jaw bone (COP) represent control groups. Samples underwent retrospective micro-CT and morphometric analysis in representative units by bone volume fraction (BV/TV), bone surface density (BS/BV), trabecular thickness (Tr.Th.), trabecular number (Tr.N.), trabecular space (Tr.Sp.), Euler characteristic for bone connectivity, bone mineral density (BMD) and tissue mineral density (TMD).A total of 141 samples from 78 patients were analyzed. BV/TV of Mexp group (mean: 0.46 ± 0.27) was significantly higher than in the COP group (mean: 0.14 ± 0.05; p = 0.0053). Tr.Th. differed significantly between the BPexp group (mean: 0.32 ± 0.15) and the Mexp group (mean: 0.57 ± 0.20; p = 0.0452) as well as between the BPOseq group (mean: 0.25 ± 0.10) and the MOseq group (mean: 0.39 ± 0.18; p = 0.0417). Signs of trabecular thickening and unorganized trabecular microarchitecture from AR-exposed- to sequestrum groups, were analyzed in 3D reconstructions. However, BS/BV, Tr.N., and Tr.Sp. showed no significant differences. Euler characteristic of the BPOseq group (median: 7.46) doubled compared to that of the BPexp group (median: 14.97; p = 0.0064). Mineralization parameters BMD and TMD were similar in all groups.Findings show evidence of enhanced bone mass and suspect microarchitecture in some AR-treated jaw bone compared to osteoporotic jaw bone. Despite increased bone mass, some MRONJ samples showed decreased trabecular connectivity by Euler characteristic compared to AR-treated jaw bone. These samples may indicate extensive ossification and ineffective bone mass with superficially higher bone mass without existing or even reduced mechanical stability, indicated by connectivity loss. This result might also suggest a high risk to microcrack accumulation. At some point, possibly some kind of over-ossification could lead to under-nourishment and microarchitectural weakness, creating instability, subsequently increasing vulnerability to MRONJ.  相似文献   
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