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61.
After experimental inoculation, severe acute respiratory syndrome coronavirus 2 infection was confirmed in bank voles by seroconversion within 8 days and detection of viral RNA in nasal tissue for up to 21 days. However, transmission to contact animals was not detected. Thus, bank voles are unlikely to establish effective transmission cycles in nature.  相似文献   
62.

There is agreement among health economists that on the whole medical innovation causes health care expenditures (HCE) to rise. This paper analyzes for which diagnoses HCE per patient have grown significantly faster than average HCE. We distinguish decedents (patients in their last 4 years of life) from survivors and use a unique dataset comprising detailed HCE of all members of a regional health insurance fund in Upper Austria for the period 2005–2018. Our results indicate that among decedents in particular, the expenditures for treatment of neoplasms have exceeded the general trend in HCE. This confirms that medical innovation for this group of diseases has been particularly strong over the last 15 years. For survivors, we find a noticeable growth in cases and cost per case for pregnancies and childbirth, and also for treatment of mental and behavioral disorders. We discuss whether these findings contradict the widespread interpretation of cost-increasing innovations as “medical progress” and offer some policy recommendations.

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63.
Köckerling  F.  Hantel  E.  Adolf  D.  Kuthe  A.  Lorenz  R.  Niebuhr  H.  Stechemesser  B.  Marusch  F. 《Hernia》2021,25(5):1169-1181
Hernia - There are hardly any studies on the outcome of scrotal compared with medial and lateral inguinal hernias. Therefore, this present multivariable analysis of data from the Herniamed Registry...  相似文献   
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Identification of quinolinic acid in rat and human brain tissue   总被引:20,自引:0,他引:20  
An analytical technique for the determination of the excitotoxic compound quinolinic acid (2,3-pyridine dicarboxylic acid) in brain tissue has been developed. Following sample prepurification by ion exchange and high pressure liquid chromatography, quinolinic acid is converted to the dihexafluoroisopropyl ester and the derivative is analyzed by mass fragmentography. Using the present technique quinolinic acid has been identified in both rat and human brain tissue.  相似文献   
68.
The key-enzyme for the metabolism of diamines in man is diamine oxidase (DAO). Its highest activities are in the intestinal mucosa, localized in the cytoplasm of the mature enterocytes of the small and large bowel. If the gut is affected by inflammation in Crohn's disease macroscopical changes are observed. This prospective study investigated if these mucosal alterations are also reflected in changes of mucosal diamine oxidase activity and/or mucosal histamine content respectively. Twenty patients (12 female, 8 male; age: , range 18 49 years) undergoing gut resection because of complications in Crohn's disease (Jan.–Dec. 1988) formed the basis of the study. Tissue samples of the resected material from areas inflamed and histologically not involved in the disease were investigated for diamine oxidase activities and histamine content. Diamine oxidase activities in the mucosa obtained from the macroscopically normal proximal (155.6; (76–393) mU/g ( range)) and distal (132; (58.5–295) mU/g) resection margins were similar to our previous findings. In all patients, however, samples from the diseased mucosa had significantly (ca. 50%) lower diamine oxidase activities (74.5; (5–262) mU/g) compared to the healthy tissue. Similar differences were found in material obtained either from whole intestinal wall or from the mucosa. The determination of diamine oxidase activity constitutes possibly a more unambiguous and earlier parameter for assessing the extent of the inflamed area than histological disease presentations. Using biopsies the necessary extent of resection could be estimatedbefore operation: this may influence operative strategies and help in the definition of the minimum amount of inflamed gut to be removed.Supported by grant of Deutsche Forschungsgemeinschaft (Lo 199/15-2).  相似文献   
69.
Based on biochemical and ligand binding studies in various tissues and species, evidence for several alpha 2-adrenergic receptor subtypes has accumulated. The current alpha 2-adrenergic receptor classification (alpha 2A, alpha 2B, alpha 2C) is based exclusively on pharmacological criteria. The molecular cloning of three distinct genes for human alpha 2-adrenergic receptors has confirmed the existence of multiple alpha 2-adrenergic receptor subtypes. According to their localization on different human chromosomes, the receptor genes were termed alpha 2-C10, alpha 2-C4, and alpha 2-C2. The relationship, however, between the pharmacologically characterized alpha 2-adrenergic receptors and the isolated genes has yet to be clarified. Using Northern blot hybridization, we analyzed the expression of the three cloned alpha 2-adrenergic receptor genes in 13 rat tissues, as well as in cell lines previously described as model systems for the pharmacologically defined alpha 2-adrenergic receptor subtypes. The alpha 2-C10 receptor corresponds to the alpha 2A subtype and is expressed in rat brainstem, cerebral cortex, hippocampus, pituitary gland, cerebellum, kidney, aorta, skeletal muscle, spleen, and lung. Messenger RNA coding for the alpha 2-C4 receptor was detected only in brain regions, not in peripheral tissues, whereas the alpha 2-C2 message was found only in liver and kidney. Hybridization experiments with RNA derived from tissues and cells from which the pharmacological alpha 2-receptor classification has been developed lead to the conclusion that the alpha 2B subtype represents two distinct receptor molecules, the alpha 2-C4 and a subtype previously undetected by classical ligand binding approaches. Furthermore, our results suggest that the alpha 2C subtype characterized in opossum kidney cells is an interspecies variation of alpha 2-C4 rather than a separate subtype. Finally, the cloned alpha 2-C2 receptor was found to be "alpha 2B-like" and not covered by the current pharmacological classification.  相似文献   
70.
T cell ignorance is a specific form of immunological tolerance. It describes the maintenance of naivety in antigen-specific T cells in vivo despite the presence of their target antigen. It is thought to mainly play a role during the steady state, when self-antigens are presented in absence of costimulatory signals and at low density or to T cells of low affinity. In how far antigen-specific T cells can also remain clonally ignorant to foreign antigens, presented in the inflammatory context of systemic infection, remains unclear. Using single-cell in vivo fate mapping and high throughput flow cytometric enrichment, we find that high-affinity antigen-specific CD8+ T cells are efficiently recruited upon systemic infection. In contrast, most low-affinity antigen-specific T cells ignore the priming antigen and persist in the naïve state while remaining fully responsive to subsequent immunization with a high-affinity ligand. These data establish the widespread clonal ignorance of low-affinity T cells as a major factor shaping the composition of antigen-specific CD8+ T cell responses to systemic infection.  相似文献   
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