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The guinea pig maximization test (GPMT) has proven to be a valuable tool for the identification of the skin sensitization potential of chemicals. The method identifies a hazard which can lead in the EC to compulsory labelling of that chemical. In the present study, data on sulphanilic acid derived from the GPMT has been compared with results from a second guinea pig assay (the cumulative contact enhancement test) and the murine local lymph node assay, both of which require only topical application of chemical. Except for the GPMT, no test identified any sensitizing activity associated with exposure to sulphanilic acid. These latter results are consistent with the experience gained from substantial human exposure in an occupational setting and from which no cases of allergic contact dermatitis to sulphanilic acid have arisen over a 20-year period. In consequence, it is questioned which test protocol in practice has given the more accurate identification of sensitization hazard relevant to man.  相似文献   
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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   
4.
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   
5.
Life expectancy in British Marfan syndrome populations   总被引:2,自引:0,他引:2  
A total of 206 patients with Marfan syndrome were ascertained throughout genetic clinics in Wales and Scotland during the period 1970–1990. There were 45 deaths representing 22% of the cohort. Mean age at death was 45.3 ± 16.5 years. 50% median cumulative survival in the total cohort (n = 206) was 53 years for males and 72 years for females. Multivariate analysis confirmed severity as the best independent indicator of survival. These findings and survival curves will assist in the counselling of British families and individuals with Marfan syndrome.  相似文献   
6.
The fine-needle aspiration cytologic findings of Wilms' tumor occurring in a 20-yr-old female patient and a 35-yr-old male patient showing blastemal, spindled sarcomatous and rare epithelial components are reported. The male patient had the typical presentation of renal mass with metastasis to lung and pleura, whereas the female patient had an unusual presentation with the tumor originated from the subcapsular nephrogenic zone of the kidney, extending into the liver without invasion into the renal cortex. Cytogenetic analysis of this case identified: 90, XXXX, +2x3-4, -5, -15, -16, -17, -17, i (17)(q10) x2. This finding may represent a genetic change associated with Wilms' tumor of older pediatric and young adult patients. To the best of our knowledge, this case is the sixth case with cytogenetic study and the first case revealing isochromosome 17q of an adult Wilms' tumor.  相似文献   
7.
OBJECTIVE: This study was undertaken to evaluate a smoking cessation intervention provided to women smokers as follow-up to cervical cancer screening. METHODS: Women who had had a Pap test in the prior month (N = 4,053) were called to complete a survey that assessed smoking status; 580 identified smokers were randomized to receive Usual care (n = 292) or a Self-help intervention (n = 288) that included a self-help booklet, a smoking and reproductive health information card, and three telephone counseling calls. Women were followed up at 6 and 15 months post-base line. RESULTS: Cessation rates in the Usual care (UC) and Self-help (SH) groups did not differ at the 6-month (UC 10.5% vs SH 10.9%, P = 0.56) or 15-month follow-up (UC 15.5% vs SH 10.6%, P = 0.17). Among women with an abnormal Pap test result there were no differences by study group in cessation rates at 6-month (UC 9.8% vs SH 11.0%, P = 0.71) or 15-month follow-up (UC 14.6% vs SH 13.4%, P = 0.96). CONCLUSION: Integrating interventions into the clinical setting and involving providers at the point of care may have greater potential for capitalizing on this "teachable moment." Copyright 1999 American Health Foundation and Academic Press.  相似文献   
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9.
The purpose of the study was to ascertain if Broca's aphasics have a comprehension defect which is dependent on syntactic relationships, to ascertain how this comprehension defect, if present, is different from that seen in Wernicke's and conduction aphasias. Twenty-six aphasic patients (nine Broca's eight conduction, nine Wernicke's) and eight controls were given a test which helped differentiate comprehension errors caused by syntactic incompetence from those caused by lexical incompetence. Wenicke's aphasics made significantly more lexical errors than each of the other groups. There were no significant differences between the lexical errors made by the other groups (Broca's, conduction, and control. There were no significant differences between Broca's and conduction aphasics, however both these groups made more syntactic errors than the controls.  相似文献   
10.
Patients have a right to consider that any information about themselves will be regarded as confidential, but inadvertently, and, very occasionally deliberately, that confidence may be broken. Therefore the principles on which the computer system at The London Hospital is based rest on maintaining confidentiality but at the same time using the facilities unique to the computer to the fullest extent for the benefit of patients. The system is described in outline, and a note is added of occasions when it would be desirable to suppress information on a patient and the reasons for so doing.  相似文献   
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