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Abstrakt 1. Nimmt ein Patient einen ihm von seinem (Zahn-)Arzt einger?umten Exklusiv-Termin nicht wahr, obwohl er auf dessen Eigenschaft ausdrücklich hingewiesen wurde, so hat er dem (Zahn-)Arzt den Behandlungsausfall abzüglich eines angemessenen Eigenanteils des (Zahn-)Arztes zu ersetzen. 2. Die Ersatzpflicht tritt auch dann ein, wenn der Patient den Termin nicht in der in dem Behandlungsvertrag vorgesehenen Frist absagt. Eine hierfür seitens des (Zahn-)Arztes bestimmte Frist von zwei Tagen vor Behandlungsbeginn stellt sich für den Patienten grunds?tzlich auch nicht als unangemessene Benachteiligung i.S. des § 307 BGB dar. 3. Ein Anspruch des Arztes entf?llt auch bei nur mündlicher Vereinbarung nicht unter dem Gesichtspunkt des § 4 Abs. 5b BMV-Z, denn diese Vorschrift ist teleologisch dahin zu reduzieren, dass nur zahn?rztliche Honoraransprüche aus erfolgten Behandlungen schriftlich vereinbart werden müssen. Soweit es jedoch um einen vertraglichen Anspruch wegen einer Leistungsst?rung geht, vermag das Schriftformerfordernis des § 4 Abs. 5b BMV-Z grunds?tzlich nicht einzugreifen. (Leits?tze des Bearbeiters)  相似文献   
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Soil ingestion can be a major route of human exposure to many immobile soil contaminants. The present risk assessment is based on toxicity studies in which contaminants are typically ingested in liquid or food matrices. The difference in bioavailability of contaminants ingested in a soil matrix is not taken into account. To become bioavailable, contaminants first need to become bioaccessible, i.e., they must be mobilized from the soil during digestion. Soil contaminants may be less bioaccessible than contaminants from liquid or food, so that the risks can be overestimated. This article describes the development of an in vitro human digestion model that is physiologically based. It can be used as a tool to assess bioaccessibility. We explain the rationale behind the experimental design of the model. We address the aspects of the simulated compartments of the gastrointestinal tract, temperature, soil-to-fluid ratio, ratio of digestive juices, transit times, centrifugation, pH values, mixing, constituents and their concentrations, and bile. The optimized in vitro digestion model was applied in a case study. The bioaccessibility of lead in pottery flakes with glazing was determined and compared to the bioaccessibility of lead in the soil from which the pottery flakes were removed. The data indicate that pottery flake lead is considerably less bioaccessible (0.3 ± 0.2%) than lead in soil without pottery flakes (42–66% at the same site, and 28–73% at other sites in the same town). Furthermore, bioaccessibility values of lead in soil appear to be less than calculated bioaccessibility values for dietary lead (which are based on the criterion used by the Dutch risk assessment and on literature absorption data). This indicates that accounting for the matrix of ingestion can affect the exposure assessment for lead. The in vitro digestion model is a promising tool for studying the effect of the ingestion matrix on bioaccessibility. Received: 23 December 2001/Accepted: 24 July 2002  相似文献   
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Early during rat thymus ontogeny, an important proportion of thymocytes expresses IL-2R and contains IL-2 mRNA. To investigate the role of the IL-2-IL-2R complex in rat T cell maturation, we supplied either recombinant rat IL-2 or blocking anti-CD25 mAb to rat fetal thymus organ cultures (FTOC) under several experimental conditions. The IL-2 treatment initially stimulated the growth of thymocytes and, as a result, induced T cell differentiation, but the continuous addition of IL-2 to rat FTOC, as well as the anti-CD25 administration, resulted in cell number decrease and inhibition of thymocyte maturation. These results indicate that immature rat thymocytes bear functional high- affinity IL-2R and that IL-2 promotes T cell differentiation as a consequence of its capacity to stimulate cell proliferation. Modifications in TCR alpha beta repertoire and increased numbers of NKR- P1+ cells, largely NK cells, were also observed in IL-2-treated FTOC. Furthermore, IL-2-responsiveness of different thymocyte subsets changed throughout thymic ontogeny. Immature CD4-CD8-cells responded to IL-2 in two stages, early in thymus development and around birth, in correlation with the maturation of two distinct waves of thymic cell progenitors. Mature CD8+ thymocytes maximally responded to IL-2 around birth, supporting a role for IL-2 in the increased proliferation of mature thymocytes observed in vivo in the perinatal period. Taken together, these findings support a role for IL-2 in rat T cell development.   相似文献   
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The present study was undertaken to assess the temporal association between the profiles of serum concentrations of oestradiol-17beta, progesterone, chorionic gonadotrophin (CG) and relaxin in pregnancies established naturally, and after embryo transfer, as well as in failed pregnancies in rhesus monkeys. In naturally mated cycles (group 1) a conception rate of 75% was obtained. In group 1, the mean day of CG detection in serum was 11.5 +/- 1.9 day post-ovulation, and for relaxin, 9.0 +/- 2.5 day post-ovulation. In group 2, embryo transfer to synchronous, non-mated surrogate recipients was performed; seven embryo transfer cycles yielded three pregnancies which were allowed to continue to term and normal infants were delivered. In embryo transfer cycles the mean day of CG detection was 14.8 +/- 1.8 day post- ovulation, and for relaxin, 11.4 +/- 2.6 day post-ovulation. A delay of about 3 days was observed in the appearance in circulation of CG (P < 0.05) and also of relaxin (P < 0.05) between natural mated and embryo transfer conception cycles. Significant differences (P < 0.05 for progesterone and P < 0.03 for oestradiol) were obtained for the areas under the curves for progesterone and oestradiol between days 12 and 16 in conception cycles compared with failed pregnancies. These data provide the first observation of the normal hormonal signals associated with maternal recognition of transferred embryos during the peri- implantation period, and suggest that the use of such an experimental primate embryo transfer model may help to elucidate components of maternal and embryonic signal-response mechanisms during embryo implantation.   相似文献   
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A rapid microagglutination test has been developed which can be performed in 30 minutes. Ninety-seven percent of 96 patients diagnosed as having Legionella pneumophila (serogroup 1) infection by indirect immunofluorescence were also detected by the rapid microagglutination test.  相似文献   
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Earlier studies found that the effectiveness of CBT for anxiety disorders and depression is not negatively affected by the presence of co‐morbid axis II disorders (for reviews, see Mulder, 2002; Dreessen & Arntz, 1998). That is to say, patients with co‐morbid axis II disorders tend to have more severe complaints post‐therapy, but they already have complaints before therapy and the decrease in symptoms is not affected by axis II disorders. In these studies the presence of axis II disorders was assessed using structured interviews. Compared to the more usual open clinical interview, structured interviews tend to result in larger proportions of the patients receiving a diagnosis of one or more personality disorders. Possibly the inclusion of many relatively mild cases obscured a negative effect of personality disorders and such a negative effect might materialize if axis II disorders were assessed with a open clinical interview. In the present study, data were analyzed from 421 patients, 289 of whom received a diagnosis of one or more personality disorders. Axis I diagnoses were obsessive–compulsive disorder (n = 165), panic disorder with agoraphobia (n = 54), major depression (n = 40), eating disorders (n = 42) or other disorders (n = 120) and CBT was delivered on an in‐patient basis. When all groups were collapsed and a general measure of axis I problems was taken, the pattern was similar to the pattern from studies using structured interviews: patients with axis II problems had higher axis I problems both before and after treatment, but the decrease was parallel. When analyzed separately patients with axis II disorders did not score higher than patients without axis II disorders, while improvement in the various axis I groups was not affected by the presence of personality disorders. In the depressed subgroup a trend was observed for patients with axis II disorders to improve less. Even when personality disorders are diagnosed using an open clinical interview, their presence is largely irrelevant to the reduction of axis I problems after CBT. Copyright © 2006 John Wiley & Sons, Ltd  相似文献   
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