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排序方式: 共有1314条查询结果,搜索用时 15 毫秒
1.
Altered serum immunoglobulin response to model intestinal antigens during dietary exposure to vomitoxin (deoxynivalenol) 总被引:1,自引:0,他引:1
The effect of dietary vomitoxin on the serum IgA and IgG responses to two model intestinal antigens, casein and cholera toxin (CT), were assessed in 4 experimental groups: (1) mice fed casein-based diet, (2) mice fed casein-based diet containing 25 ppm vomitoxin, (3) mice fed casein-based diet and immunized with CT, and (4) mice fed casein-based diet containing 25 ppm vomitoxin and immunized with CT. Unimmunized and CT-immunized mice that were fed vomitoxin exhibited increased levels of total serum IgA relative to matched control animals fed the standard diet. Relative concentrations of casein-specific IgA were greater in both unimmunized mice and CT-immunized mice fed standard diet with vomitoxin than in matched controls fed standard diet only. CT-specific serum IgA in CT-immunized mice was not affected by vomitoxin feeding, but relative levels of CT-specific IgA were higher in unimmunized mice fed vomitoxin than in unimmunized mice fed standard diet. Both casein- and CT-specific serum IgG were depressed in mice fed vomitoxin. Significant differences in total, casein-specific and CT-specific IgA within the intestinal contents were not observed between CT-immunized mice fed vomitoxin and those fed the control diet. The results suggest that vomitoxin altered regulation of the normal immunoglobulin response to intestinal antigens and that this was manifested in the systemic compartment. 相似文献
2.
AM Manganoni† C Farisoglio† G Tucci† F Facchetti‡ PG Calzavara Pinton† 《Journal of the European Academy of Dermatology and Venereology》2007,21(10):1333-1336
BACKGROUND: Development of more than one primary melanoma in a patient is a relatively uncommon but well-recognized phenomenon. Its frequency has ranged from 1.2% to 8.2% in several series. This subgroup of patients with multiple primary lesions has not been characterized sufficiently. We report the experience of the Melanoma Unit of University Hospital Spedali Civili of Brescia, Italy. METHOD: Study subjects were drawn from 1240 patients with histologically confirmed melanoma, including melanoma in situ. From this group, multiple melanomas developed in 47 patients (3.79%). Every one of our patients has been taught to perform self-examination of the skin to detect suspicious pigmented lesions. RESULTS: Of the 47 patients described in this study, 38 had two primary melanomas, 7 had three melanomas and 2 had 5 and 10 melanomas, respectively. Mean age at first diagnosis was 46.2 years. The majority of subsequent melanomas (74.5%) were removed within 5 years of the initial operation. Synchronous lesions were found in 10 patients. In male patients, the lesion appeared most frequently on the trunk; in female patients, melanoma appeared mostly on the lower extremities. The second primary melanomas developed in the same anatomic region from the first in 53.2% of our patients. The proportion of in situ to invasive melanomas was greater for the second melanomas compared with the first melanomas. Regarding invasive melanomas, the mean thickness of the first melanomas was 1.31 mm compared with 0.66 mm for the second ones. Dividing patients into two groups, of more and less than 50, it is highlighted that in older patients synchronous lesions appear more frequently (36.4% vs. 8.0%); the median time interval between sequential melanomas is longer (84 vs. 63.7 months); and the ratio between the primary and secondary melanoma mean thickness is lower (1.21 : 1.08 vs. 1.43 : 0.63 mm). CONCLUSIONS: The study confirms that second primary melanoma is usually thinner than the first lesion, and it is more common in the same region of the body as the initial melanoma. The highest risk for a second melanoma is during the first 5 years, but a much longer time interval of 28 years is possible. Continued medical follow-up with complete skin examinations seems prudent, but it is very important to promote self-skin evaluation in patients to detect not only metastases but also subsequent primary melanomas in their earliest phases. 相似文献
3.
We have determined a critical period for vestibular development in zebrafish by using a bioreactor designed by NASA to simulate microgravity for cells in culture. A critical period is defined as the briefest period of time during development when stimulus deprivation results in long lasting or permanent sensory deficits. Zebrafish eggs were collected within 3 hours of being laid and fertilized. In experiment 1, eggs were placed in the bioreactor at 3, 24, 30, 36, 48, or 72 hours postfertilization (hPF) and maintained in the bioreactor until 96 hPF. In experiment 2, eggs were placed in the bioreactor immediately after they were collected and maintained in the bioreactor until 24, 36, 48, 60, 66, 72, or 96 hPF. Beginning at 96 hPF, all larvae had their vestibulo-ocular reflexes (VOR) evaluated once each day for 5 days. Only larvae that hatched from eggs that were placed in the bioreactor before 30 hPF in experiment 1 or removed from the bioreactor later than 66 hPF in experiment 2 had VOR deficits that persisted for at least 5 days. These data suggest a critical period for vestibular development in the zebrafish that begins before 30 hPF and ends after 66 hPF. To confirm this, zebrafish eggs were placed in the bioreactor at 24 hPF and removed at 72 hPF. VORs were evaluated in these larvae once each day for 5 days beginning at 96 hPF. These larvae had VOR deficits that persisted for at least 5 days. In addition, larvae that had been maintained in the bioreactor from 24 to 66 hPF or from 30 to 72 hPF, had only temporary VOR deficits. In a final experiment, zebrafish eggs were placed in the bioreactor at 3 hPF and removed at 96 hPF but the bioreactor was turned off from 24 hPF to 72 hPF. These larvae had normal VORs when they were removed from the bioreactor at 96 hPF. Taken as a whole, these data support the idea that there is a critical period for functional maturation of the zebrafish vestibular system. The developmental period identified includes the timeframe during which the vestibular primary afferent neurons are born, innervate their central and peripheral targets, and remodel their central projections. 相似文献
4.
E D Schmidt E D Schmidt R van der Gaag R Ganpat L Broersma P A de Boer A F Moorman W H Lamers W M Wiersinga L Koornneef 《The Journal of endocrinology》1992,133(1):67-74
The correlation between the occurrence of Graves' ophthalmopathy and Graves' hyperthyroidism may indicate a role for tri-iodothyronine (T3) hormone in the pathogenesis of Graves' ophthalmopathy. In Graves' ophthalmopathy the recti eye muscles are greatly enlarged whereas skeletal muscles seem unaffected. The distribution of the nuclear T3 receptor was studied in normal human and rat eye and skeletal muscles with immunohistochemistry using mouse (monoclonal) antibodies, and by in-situ hybridization for the detection of mRNA encoding the T3-receptor protein. Nuclear staining with T3-receptor antibodies was found in all types of tissues studied. Cytoplasmic staining occurred predominantly in the muscle fibres of the orbital layer of the eye muscles and was generally absent or very low in skeletal muscle fibres and hepatocytes. Immunostaining could be inhibited by preabsorbing the antibodies with bacterially expressed T3-receptor protein, implying specificity. The presence of nuclear and cytoplasmic hormone-free T3 receptor sites was indicated after preincubation of sections with T3 hormone; T3-receptor immunostaining decreased and T3-hormone staining increased. In-situ hybridization clearly revealed the presence of alpha-1 and beta-1 forms of the T3-receptor mRNA in liver, skeletal muscles, and orbital and intermediate layers of the eye muscles. The data demonstrate the presence of T3 hormone-receptor molecules in the extraocular and skeletal muscles. The different susceptibilities of these muscles to Graves' hyperthyroidism may relate to the quantitative differences in T3 hormone-receptor distribution. 相似文献
5.
Martineau M Jalali GR Barber KE Broadfield ZJ Cheung KL Lilleyman J Moorman AV Richards S Robinson HM Ross F Harrison CJ 《Genes, chromosomes & cancer》2005,43(1):54-71
This study was undertaken in order to compare the interphase and metaphase cytogenetics of 28 patients with ETV6/RUNX1 positive acute lymphoblastic leukemia, at diagnosis and relapse. The median time to relapse was 26 months. The significant fusion positive population heterogeneity revealed at interphase by a commercial probe for ETV6/RUNX1 fusion has not been described before. Six diagnostic samples had a single abnormal population; others had up to five each, which differed in the numbers of RUNX1 signals, and in the retention or loss of the second ETV6 signal. In contrast, the number of fusion signals was more constant. At relapse, there were fewer populations; the largest or unique clone was sometimes a re-emergence of a minor, diagnostic one, with a retained copy of ETV6 and the most RUNX1 signals. Abnormal, fusion negative clones were identified in bone marrow samples at extra-medullary relapse. Variant three or four-way translocations, which involved chromosomes 12 and 21, were prominent among the complex rearrangements revealed by metaphase FISH. The frequency of their occurrence at diagnosis and reappearance at relapse, sometimes accompanied by minor clonal evolution, was another new observation. Other recurrent cytogenetic features included a second copy of the fusion signal in six cases, partial duplication of the long arm of the X chromosome in two cases, and trisomy 10 in three cases. In comparing our data with previously reported cases, a picture is beginning to emerge of certain diagnostic features, which may provide circumstantial evidence of an increased risk of relapse. 相似文献
6.
Dynamic patterns of expression of BMP isoforms 2, 4, 5, 6, and 7 during chicken heart development 总被引:2,自引:0,他引:2
Somi S Buffing AA Moorman AF Van Den Hoff MJ 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2004,279(1):636-651
Bone morphogentic proteins (BMPs) play an important role in cardiac development. Using an in vitro explant analysis, we show that BMPs are crucial for myocardium formation. As a first approach to identify which BMP may be involved in myocardium formation in intra- and extracardiac mesenchyme in vivo, a survey of the expression patterns of BMP2, -4, -5, -6, and -7 mRNA is prepared by in situ hybridization in chicken embryonic hearts from HH5 to 44. During recruitment of mesodermal cells to the outflow tract myocardium (HH10-23), BMP2, -4, -5, and -7 mRNA are expressed in the distal myocardial border and the flanking mesenchyme. After completion, BMP2 and -4 mRNA become restricted to the mesenchyme and BMP5 and -7 mRNA to the myocardium. At the venous pole, BMP2, -5, and -7 mRNA are expressed in the distal myocardial border of the caval vein, while BMP2, -5, -6, and -7 mRNA are expressed in the distal myocardium around the pulmonary vein. BMP4 mRNA is expressed in the adjacent mesenchyme at both sides. During muscularization of the atrioventricular cushions and the tricuspid valve, the cardiomyocytes that protrude into the mesenchyme express BMP2, -4, -5, and -7 mRNA, whereas BMP6 mRNA is expressed in the cushion mesenchyme. The myocardial protrusions formed in the mesenchymal proximal outlet septum express BMP4, -5, and -7 mRNA, while BMP2 and -6 mRNA are expressed in the mesenchyme. The spatiotemporal expression patterns of these BMPs in relation to myocardium formation at the distal ends and within the heart suggest a role for BMPs in myocardium formation. During delamination of the valves, BMP4 and -6 mRNA are expressed at the ventricular side of the forming mitral valve, BMP4 mRNA at the ventricular side of the forming tricuspid valve, and BMP2, -4, and -6 mRNA at the vascular side of the forming semilunar valves. 相似文献
7.
Tortoriello DV; McGovern PG; Colon JM; Loughlin J; Santoro N 《Human reproduction (Oxford, England)》1998,13(11):3005-3008
We report an instance of critical ovarian hyperstimulation syndrome in a
highly responsive in-vitro fertilization patient despite the preventive
measure of a 4 day 'coast' interval during which no gonadotrophins were
administered while gonadotrophin-releasing hormone agonist therapy
continued until serum oestradiol concentrations fell below 3000 pg/ml.
相似文献
8.
9.
Ricardo Pietrobon Anand Shah Paul Kuo Matthew Harker Mariana McCready Christeen Butler Henrique Martins CT Moorman Danny O Jacobs 《BMC medical informatics and decision making》2006,6(1):32-11
Background
Although regulatory compliance in academic research is enforced by law to ensure high quality and safety to participants, its implementation is frequently hindered by cost and logistical barriers. In order to decrease these barriers, we have developed a Web-based application, Duke Surgery Research Central (DSRC), to monitor and streamline the regulatory research process. 相似文献10.