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91.
92.
Katharina A. Remer Marita Bartrow Bianca Roeger Heidrun Moll Ulrich Sonnenborn Tobias A. Oelschlaeger 《International journal of medical microbiology : IJMM》2009,299(7):467-478
Enterotoxigenic Escherichia coli (ETEC) are a leading cause of diarrhoea in piglets and newborn calves. Massive efforts have therefore been made to develop a vaccine for the induction of protective mucosal immunity against ETEC. Since it has been shown that the probiotic strain E. coli Nissle 1917 (EcN) can serve as a safe carrier for targeted delivery of recombinant molecules to the intestinal mucosa, we constructed the recombinant strain EcN pMut2-kanK88 (EcN-K88) stably expressing the determinant for the K88 fimbrial adhesin of ETEC on the bacterial surface.After oral application of EcN-K88 to mice for one week, EcN-K88 as well as wild-type EcN and EcN mock-transformed with the plasmid vector only could be detected in faecal samples for a minimum of 7 days after the last feeding, indicating that EcN can transiently colonise the murine intestine. Oral application of EcN-K88 resulted in significant IgG serum titres against K88 as early as 7 days after the initial feeding with EcN-K88, but no significant IgA titres. In contrast, we failed to detect any specific T cell responses towards the K88 antigen both in spleen and mesenteric lymph nodes. Although dendritic cells readily upregulated maturation and activation markers in response to K88 stimulation, accompanied by secretion of interleukin (IL)-12, IL-6, IL-10, and tumour necrosis factor, restimulation of T cells from mice having received EcN-K88 with K88-loaded dendritic cells did not result in detectable T cell proliferation and IL-2 secretion, but rather induced an IL-10 bias. While the serum antibody responses clearly demonstrate that K88 is recognized by the humoral immune system, our findings indicate that oral application of probiotic EcN expressing the K88 fimbrial adhesin does not induce a selective T cell response towards the antigen. 相似文献
93.
Between 1933 and 1945, German medical practitioners were easily persuaded to align themselves with Nazi ideology. Jewish urologists were forced out of academia, editorial boards of medical journals and medical practice. Like most German physicians, urologists quickly accepted their new role as caretakers of public health instead of individual patients’ wellbeing. The specialty of urology profited from this collaboration with Nazi policies as it gained further independence. 相似文献
94.
Johan K Sandberg Markus Moll 《Clinical cancer research》2007,13(14):4311; author reply 4311-4311; author reply 4312
95.
Visual Functioning Questionnaire: reevaluation of psychometric properties for a group of working-age adults. 总被引:3,自引:0,他引:3
Maaike Langelaan Ruth M A van Nispen Dirk L Knol Annette C Moll Michiel R de Boer Bill Wouters Ger H M B van Rens 《Optometry and vision science》2007,84(8):775-784
PURPOSE: The Visual Functioning Questionnaire (VFQ-25) is one of the most widely used measures of vision-related quality of life. However, the questionnaire does not meet some psychometric quality criteria. The objectives of this study were first to obtain the factor structure of the VFQ-25, and second, to obtain interval scales by Rasch analysis. METHODS: The questionnaire was administered to 129 visually impaired adults (mean age 42.1 years; range 21 to 67 years). First, the items of the VFQ-25 were subjected to an exploratory factor analysis with Promax rotation. Next, we performed a separate Rasch analysis on each factor. We examined step thresholds and goodness of fit statistics of the items. Finally, we examined differential item functioning. RESULTS: Factor analysis indicated four factors: Near Activities, Distance Activities and Mobility, Mental Health and Dependency, and Pain and Discomfort. They accounted for 46.37% of the total variance. Most items showed some degree of disordering. After collapsing response categories, all items showed ordered thresholds. The Near Activities domain showed excellent fit, whereas the Distance Activities and Mobility domain, the Mental Health and Dependency domain, and the Pain and Discomfort domain had an unsatisfactory fit. There were two items showing uniform differential item functioning. CONCLUSIONS: The four-factor structure of the VFQ-25 largely confirms the structure of the questionnaire. However, the results of this study suggest that modifications of the original VFQ-25 structure are necessary. 相似文献
96.
We tested the hypothesis that growth hormone (GH) mediates the rise in insulin-like growth factor I (IGF-I) concentrations in children with precocious puberty. We studied three groups of patients. Group 1 included six children with GH deficiency and precocious puberty (precocious GH-deficient); group 2 included 10 GH-sufficient patients with idiopathic true precocious puberty (precocious GH-sufficient); and group 3 included 9 prepubertal children with GH deficiency (prepubertal GH-deficient). Growth rates, pubertal status, and plasma IGF-I concentrations were determined at regular intervals. The precocious children with GH deficiency had a mean (+/- SD) growth rate of 7.2 +/- 2.1 significantly below that of the precocious GH-sufficient patients (10.5 +/- 2.5 cm/yr, p less than 0.05) but above that of the prepubertal GH-deficient children (3.9 +/- 1.4 cm/yr, p less than 0.05). The mean IGF-I concentration in the precocious GH-deficient children was 0.77 +/- 0.39 U/ml, significantly lower than the mean level of 2.2 +/- 0.67 U/ml in the precocious GH-sufficient patients (p less than 0.01). However, precocious GH-deficient patients had significantly higher IGF-I values than the prepubertal GH-deficient children (0.24 +/- 0.10 U/ml, p less than 0.05). IGF-I values did not rise with the onset of precocious puberty in four of the precocious GH-deficient children evaluated before and after the development of precocious puberty. However, three patients who began GH treatment did have a rise in plasma IGF-I concentrations to levels of 1.2, 3.4, and 3.7 U/ml, respectively. These findings are compatible with the concept that sex steroids increase IGF-I levels in precocious puberty primarily by increasing GH production. A small but direct effect of sex steroids on IGF-I production may also exist. The onset of precocious puberty in children with organic GH deficiency may mask the abnormal growth pattern of these children and delay diagnosis; determinations of plasma IGF-I concentrations may be helpful in assessing the GH status of these patients. 相似文献
97.
R. Engers F. van Roy T. Heymer U. Ramp R. Moll M. Dienst U. Friebe A. Pohl H. E. Gabbert C. D. Gerharz 《British journal of cancer》1996,73(4):491-498
Epithelioid sarcoma is a highly malignant soft tissue tumour that is refractory to conventional chemotherapy and irradiation. Since permanent cell lines of this tumour are extremely rare, in vitro data on compounds with significant antiproliferative effects are still lacking. Therefore, we investigated the effects of retinoic acid (RA) and tumour necrosis factor alpha (TNF-alpha) on tumour cell proliferation of three different clonal subpopulations (GRU-1A, GRU-1B, GRU-1C) derived from the same human epithelioid sarcoma cell line, GRU-1. In GRU-1A both RA (P=0.01) and TNF-alpha (P=0.002) exhibited highly significant and dose-dependent growth inhibitory effects, which could further be increased by a combined application of both compounds (P<0.006). GRU-1B proved to be sensitive to RA (P=0.006), whereas no response to TNF-alpha was observed. GRU-1C was resistant to both RA and TNF-alpha. The antiproliferative effect of TNF-alpha was mediated by TNF receptor 1(TNF-R1) and correlated positively with both the number of TNF-R1 per cell and receptor affinity. No correlation was detected between RA-induced growth inhibition and the expression pattern of the RA receptors (RARs) RAR-alpha, RAR-beta, and RAR-gamma. Plating efficiency, however, could exclusively be reduced by RA in GRU-1B, the only cell line expressing RAR-alpha. Taken together, these data are the first showing significant antiproliferative effects in human epithelioid sarcoma by RA and TNF-alpha. Whereas the TNF-alpha response seems to depend on the expression of TNF-R1, no simple correlation could be found between RA sensitivity and the expression pattern of RARs. 相似文献
98.
Administration of low-dose estrogen rapidly and directly stimulates growth hormone production 总被引:2,自引:0,他引:2
G W Moll R L Rosenfield V S Fang 《American journal of diseases of children (1960)》1986,140(2):124-127
We tested the concept that estrogen directly stimulates growth hormone (GH) production by determining whether low-dose treatment with ethinyl estradiol increases the GH reserve, as assessed by levodopa administration, without inhibiting somatomedin-C (Sm-C) levels. Twenty-three prepubertal short normal children underwent levodopa tests before and after being treated with ethinyl estradiol. One bedtime dose of ethinyl estradiol (20 to 40 micrograms/sq m, n = 8) resulted in a significant increase in GH levels during levodopa testing, with no significant change in Sm-C levels (0.27 +/- 0.03 vs 0.36 +/- 0.1 units/mL). Two days of a comparable ethinyl estradiol dose (n = 12) raised the mean basal GH level (2.4 +/- 0.4 vs 9 +/- 3 ng/mL) and had a similar effect on peak GH response, without affecting the mean Sm-C level. Eighteen of the 23 patients responded (maximum GH level, greater than or equal to 7 ng/mL) to levodopa before estrogen; all 20 children who received ethinyl estradiol priming in a dose of 20 micrograms/sq m or more also responded. We conclude that low-dose estrogen therapy rapidly stimulates GH production without decreasing Sm-C plasma levels. These results support the concept that the estrogen effect is direct. This action may be important for the stimulation of growth by estrogen. This effect can be conveniently employed to enhance the specificity of the levodopa test for profound GH deficiency. 相似文献
99.
Introduction. Bypass grafting to the peroneal artery (PA) is supposed to be technical demanding. A modified approach to the peroneal artery can simplify this operative procedure. Method. Preparation of the PA is performed by a lateral incision along the margo posterior of the fibula. Without dissection of musculature direct preparation of the PA with it's corresponding veins behind the fibula is possible. Results. This technique was first performed in a patient, when a large tibial ulcer prohibeted a standard medial approach. Since this introduction, the procedure with femoro-peroneal bypass grafting was performed three other times. In no case technical and perioperative complications were observed, all grafts are still patent. Conclusion. The dorsolateral approach to the PA appears as an elegant alternative to the conventional techniques. Besides a distinct reduction of operative trauma it allows a reduction of preparaion time. Additionally, a reduction of approach-dependent complications can be presumed. 相似文献
100.