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1.
Intravenous ganciclovir is the standard treatment for cytomegalovirus disease in solid organ transplant recipients. Oral valganciclovir is a more convenient alternative. In a randomized, international trial, recipients with cytomegalovirus disease were treated with either 900 mg oral valganciclovir or 5 mg/kg i.v. ganciclovir twice daily for 21 days, followed by 900 mg daily valganciclovir for 28 days. A total of 321 patients were evaluated (valganciclovir [n = 164]; i.v. ganciclovir [n = 157]). The success rate of viremia eradication at Day 21 was 45.1% for valganciclovir and 48.4% for ganciclovir (95% CI -14.0% to +8.0%), and at Day 49; 67.1% and 70.1%, respectively (p = NS). Treatment success, as assessed by investigators, was 77.4% versus 80.3% at Day 21 and 85.4% versus 84.1% at Day 49 (p = NS). Baseline viral loads were not different between groups and decreased exponentially with similar half-lives and median time to eradication (21 vs. 19 days, p = 0.076). Side-effects and discontinuations of assigned treatment (18 of 321 patients) were comparable. Oral valganciclovir shows comparable safety and is not inferior to i.v. ganciclovir for treatment of cytomegalovirus disease in organ transplant recipients and provides a simpler treatment strategy, but care should be taken in extrapolating to organ transplant recipients not properly represented in the present study.  相似文献   
2.
Abstract It is a fundamental assumption in nursing theory that it is important for nurses to understand how patients think about themselves and the contexts they are in. According to modern theories of hermeneutics, a nurse and a patient must share the same concepts in order to communicate beliefs with the same content. But nurses and patients seldom understand medical concepts in exactly the same way, so how can this communicative aim be achieved in interaction involving medical concepts? The article uses a theory of concepts from recent cognitive science and philosophy of mind to argue that nurses and patients can share medical concepts despite the diversity of understanding. According to this theory, two persons who understand medical language in different ways will nevertheless possess the same medical concepts if they agree about the normative standards for the applications of the concepts. This entails that nurses and patients normally share medical concepts even though patients’ conceptions of disease and illness are formed in idiosyncratic ways by their social and cultural contexts. Several practical implications of this argument are discussed and linked to case studies. One especially important point is that nurses should seek to make patients feel comfortable with deferring to a medical understanding. In many cases, an adequate understanding of patients presupposes that nurses manage to do this. Another implication is that deference‐willingness to normative meaning is not equivalent to the actual application of concepts. Deference‐willingness should rather be thought of as a pre‐communicative attitude that it is possible for patients who are not fully able to communicate to possess. What is important is that nurses and patients have the intention of conforming to the same meaning.  相似文献   
3.
Serial serum samples from the 21 HIV-infected Norwegian hemophiliacs have been assayed for the presence of HIV antigen and antibodies to HIV specific for the core protein p24 and the envelope protein gp41. HIV antigen was detected in 4 patients, of whom 3 have developed AIDS to date. HIV antigen appeared in serum 10 to 24 months before the diagnosis in these patients. Antibodies to gp41 was a constant finding. Antibodies to p24 disappeared from the serum in 1 patient who developed AIDS and from 3 persons free of symptoms related to the HIV infection. The detection of HIV antigen in HIV antibody-positive hemophiliacs appears to be of considerable prognostic significance.  相似文献   
4.
Cytomegalovirus (CMV) infection is associated with leucocyte infiltration in various organs, which supports a role for chemokines and adhesion molecules in the pathogenesis of CMV infection. In a prospectively conducted study of renal transplant recipients, 10 patients with CMV disease, five patients with asymptomatic CMV infection and 10 patients who did not have any CMV infection were included. During CMV infection, and in particular during CMV disease, plasma levels of the chemokines IL-8, macrophage inflammatory protein-1alpha (MIP-1alpha) and monocyte chemotactic protein-1 (MCP-1) and the soluble adhesion molecules vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1) and L-selectin increased and were positively correlated with the degree of CMV pp65 antigenaemia. Furthermore, a decrease in plasma levels of these chemokines and adhesion molecules was observed following ganciclovir therapy in the patients with CMV disease. This could suggest a role for these molecules in the pathogenesis of CMV infection.  相似文献   
5.
Summary When guinea pigs were sensitized to tuberculin by exposure to complete Freund's adjuvant the size of the intradermal PPD test was positively correlated to the body weigth of the animal. Old Tuberculin showed stimulating effect in a subsequent sensitization to merthiolate (thimerosal). The high frequency of delayed cutaneous allergy to merthiolate in the Swedish population is probably explained by sensitization through intradermal testing with tuberculin containing merthiolatc as a preservative.
Zusammenfassung Bei Meerschweinen, die mit Hilfe von Freunds Adjuvant gegen Tuberculin sensibilisiert wurden, konnte eine Korrelation zwischen der Größe des Intracutantests und dem Körpergewicht der Tiere festgestellt werden. Old Tuberculin zeigte in einem darauffolgenden Sensibilisierungsversuch mit Merthiolat einen stimulierenden Effekt auf die allergische Reaktion gegen Merthiolat. Die hohe Frequenz von allergischen cutanen Spätreaktionen gegen Merthiolat in der schwedischen Bevölkerung ist wahrscheinlich als Sensibilisierung durch Intracutantest mit Tuberculin, das als Konservierungsmittel Merthiolat enthält, zu erklären.
  相似文献   
6.
Canavan disease is caused by mutations in aspartoacylase, the enzyme that degrades N-acetylaspartate (NAA) into acetate and aspartate. Murine aspartoacylase (mASPA) was cloned using sequence information from mouse expressed sequence tags homologous to the human cDNA. The open reading frame was cloned into a thioredoxin fusion vector, overexpressed in bacteria, and the protein was purified using affinity chromatography to near homogeneity. Recombinant human ASPA (hASPA) was prepared by a similar method. Both recombinant enzymes were highly specific to NAA, with about 10% of the NAA activity toward N-acetylasparagine. More interestingly, the product of N-acetylasparagine was aspartate but not asparagine, indicating that ASPA catalyzed deacetylation as well as hydrolysis of the beta acid amide. Our success in preparing the recombinant ASPA in high purity should permit multiple lines of investigations to understand the pathogenic mechanisms of Canavan disease and the functional roles of NAA.  相似文献   
7.
Recent research has highlighted how parental narratives can be important in the resistance against disabling processes. This article contains analyses of enabling language in narratives published by Scandinavian disability rights organizations. First, drawing on the work of Fisher and Goodley, I point out that the material constitute a threefold: normality narratives, resistance narratives, and narratives that demonstrate an appreciation of the present and the child’s individual alterity. Second, I demonstrate that the last narrative draws on Romanticism rather than linguistic resources from disability culture. Third, I show that these narratives are hyperboles – texts that strengthen and emphasise the valuation to the point where the narrative structure transcends narrative consistency. Fourth, drawing on the work of Kristeva, I argue that this form of narration constitutes an intimate politics of love.  相似文献   
8.
Melanopsin is the photopigment that confers light sensitivity on intrinsically photosensitive retinal ganglion cells. Mammalian intrinsically photosensitive retinal ganglion cells are involved in the photic synchronization of circadian rhythms to the day-night cycle. Here, we report molecular components of melanopsin signaling using the cultured Xenopus dermal melanophore system. Photo-activated melanopsin is shown to initiate a phosphoinositide signaling pathway similar to that found in invertebrate photo-transduction. In melanophores, light increases the intracellular level of inositol trisphosphate and causes the dispersion of melanosomes. Inhibition of phospholipase C and protein kinase C and chelation of intracellular calcium block the effect of light on melanophores. At least four proteins, 43, 74, 90, and 134 kDa, are phosphorylated by protein kinase C upon light stimulation. This provides evidence of an invertebrate-like light-activated signaling cascade within vertebrate cells.  相似文献   
9.
Pathogens in the gastrointestinal tract exist within a vast population of microbes. We examined associations between pathogens and composition of gut microbiota as they relate to Shigella spp./enteroinvasive Escherichia coli infection. We analyzed 3,035 stool specimens (1,735 nondiarrheal and 1,300 moderate-to-severe diarrheal) from the Global Enteric Multicenter Study for 9 enteropathogens. Diarrheal specimens had a higher number of enteropathogens (diarrheal mean 1.4, nondiarrheal mean 0.95; p<0.0001). Rotavirus showed a negative association with Shigella spp. in cases of diarrhea (odds ratio 0.31, 95% CI 0.17–0.55) and had a large combined effect on moderate-to-severe diarrhea (odds ratio 29, 95% CI 3.8–220). In 4 Lactobacillus taxa identified by 16S rRNA gene sequencing, the association between pathogen and disease was decreased, which is consistent with the possibility that Lactobacillus spp. are protective against Shigella spp.–induced diarrhea. Bacterial diversity of gut microbiota was associated with diarrhea status, not high levels of the Shigella spp. ipaH gene.  相似文献   
10.
Patients with common variable immunodeficiency (CVID) have reduced numbers and frequencies of dendritic cells (DCs) in blood, and there is also evidence for defective activation through Toll‐like receptors (TLRs). Collectively, these observations may point to a primary defect in the generation of functional DCs. Here, we measured frequencies of plasmacytoid DCs (pDCs) and myeloid DCs (mDCs) in peripheral blood of 26 CVID patients and 16 healthy controls. The results show that the patients have reduced absolute counts of both subsets. However, the decreased numbers in peripheral blood were not reflected in reduced frequencies of CD34+ pDC progenitors in the bone marrow. Moreover, studies at the single cell level showed that DCs from CVID patients and healthy controls produced similar amounts of interferon‐α or interleukin‐12 and expressed similar levels of activation markers in response to human cytomegalovirus and ligands for TLR‐7 and TLR‐9. The study represents the most thorough functional characterization to date, and the first to assess bone marrow progenitor output, of naturally occurring DCs in CVID. In conclusion, it seems unlikely that CVID is secondary to insufficient production of naturally occurring DCs or a defect in their signalling through TLR‐7 or TLR‐9.  相似文献   
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