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981.
Fluorescence in situ hybridization (FISH) with α-satellite DNA probes was used to study whole-arm chromosome translocation products in a family in which the propositus was shown to have a monosomy 18p/trisomy 20p imbalance. By this approach, we show that the chromosome 18 α-satellite DNA block is split into 2 smaller units, whereas the chromosome 20 breakpoint is not included within the α-satellite DNA region. We found no evidence to suggest that this split α-satellite DNA region has reduced or impaired the function of the centromere or that it contributed to the phenotype of the propositus. The FISH technique critically demonstrated the involvement of a whole-arm translocation in this case and provided accurate identification of breakpoints, which was not possible with standard banding techniques. © Wiley-Liss, Inc. 相似文献
982.
Peptides may function as neurotransmitters liberated antidromically by sensory nerve fibres, provoking vascular responses having potential importance in some neurological disorders. Dose-response relaxation curves induced by substance P (SP) and calcitonin gene related peptide (CGRP) have been studied in porcine ophthalmic arteries in vitro. Both peptides induced vasodilation when tested separately (CGRP much greater than SP). Because of the putative interactions between such peptides in this vascular territory, a computerised system was also used for analysing over time the response to a single addition of either 10(-8) M CGRP, 10(-8) M SP or a combination of 10(-8) M SP + 10(-8) M CGRP. SP did not augment the maximum relaxation induced by CGRP alone, but increased significantly the rate of relaxation during the initial phase of the response. The effect induced by the SP+CGRP combination was stronger than the sum of the individual SP and CGRP-induced relaxations during the first 4 min of the response, which suggests a SP-CGRP synergism in this artery. 相似文献
983.
984.
985.
F St?hlberg A Ericsson B Nordell C Thomsen O Henriksen B R Persson 《Acta radiologica (Stockholm, Sweden : 1987)》1992,33(3):179-200
The present work is intended as a nonmathematical review of the role of flow and motion in nuclear magnetic resonance (MR) imaging. A historical review of MR flow measurement techniques is given, followed by a short overview of flow models in vitro and in vivo. The theory behind the influence of motion on the modulus and phase MR signal information is discussed and effects such as washin/washout, flow-induced signal void, phase offset, and phase dispersion are defined. A simple approach to the concept of MR angiography is given, and methods for quantitative flow measurements such as the phase mapping technique, are surveyed. Aspects of the measurement of diffusion and microcirculation are given, and finally, an overview of the role of MR flow imaging in present and future clinical application is given. 相似文献
986.
B Lal R R Indurti P O Couraud G W Goldstein J Laterra 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(21):9695-9699
The delivery of therapeutic genes to primary brain neoplasms opens new opportunities for treating these frequently fatal tumors. Efficient gene delivery to tissues remains an important obstacle to therapy, and this problem has unique characteristics in brain tumors due to the blood-brain and blood-tumor barriers. The presence of endothelial mitogens and vessel proliferation within solid tumors suggests that genetically modified endothelial cells might efficiently transplant to brain tumors. Rat brain endothelial cells immortalized with the adenovirus E1A gene and further modified to express the beta-galactosidase reporter were examined for their ability to survive implantation to experimental rat gliomas. Rats received 9L, F98, or C6 glioma cells in combination with endothelial cells intracranially to caudate/putamen or subcutaneously to flank. Implanted endothelial cells were identified by beta-galactosidase histochemistry or by polymerase chain reaction in all tumors up to 35 days postimplantation, the latest time examined. Implanted endothelial cells appeared to cooperate in tumor vessel formation and expressed the brain-specific endothelial glucose transporter type 1 as identified by immunohistochemistry. The proliferation of implanted endothelial cells was supported by their increased number within tumors between postimplantation days 14 and 21 (P = 0.015) and by their expression of the proliferation antigen Ki67. These findings establish that genetically modified endothelial cells can be stably engrafted to growing gliomas and suggest that endothelial cell implantation may provide a means of delivering therapeutic genes to brain neoplasms and other solid tumors. In addition, endothelial implantation to brain may be useful for defining mechanisms of brain-specific endothelial differentiation. 相似文献
987.
Mycobacterium gastri arthritis: septic arthritis due to Mycobacterium gastri in a patient with a renal transplant 总被引:1,自引:0,他引:1
C E Perandones A J Roncoroni N S Frega H M Bianchini O Hübscher 《The Journal of rheumatology》1991,18(5):777-778
We describe an 18-year-old man with a renal transplant who developed septic metacarpophalangeal arthritis due to Mycobacterium gastri. He had several episodes of crystal induced synovitis, and treatment with intraarticular steroids was complicated 3 months later by iatrogenic septic arthritis. Appropriate treatment based on in vitro drug susceptibility was successful. This seems to be the first case of articular infection and the third report of human infection caused by this atypical mycobacteria. 相似文献
988.
We describe a patient with panhypopituitarism and adrenal insufficiency associated with systemic AA-amyloidosis caused by tuberculosis. This case demonstrates the ongoing process of amyloidosis, despite a presumed cure for the tuberculosis more than 30 years previously. Difficulties in recognizing clinical symptoms and interpreting laboratory data in a patient on regular haemodialysis are discussed. 相似文献
989.
In 1993, a case-control study by the Health and Safety Executive (HSE) assessed the risk of leukaemia and non-Hodgkin's lymphoma (LNHL) among children of fathers employed at the Sellafield nuclear installation in relation to paternal preconceptional irradiation (PPI). It concluded that the statistical association between risk of LNHL and PPI was confined to children born in the village of Seascale, where the dose-response was extremely high and very significant. In contrast, in 2002, a Cumbrian birth cohort study, investigating largely the same cases, concluded that this statistical association was not significantly different among children born inside and outside Seascale and estimated the dose-response inside Seascale to be much lower. This review makes a detailed comparison of the two studies, considering their design, data and analyses. The differences between their findings are due to: (i) differences in the distribution of offspring-years which are differential with respect to dose category and Seascale birth status, (ii) a non-Seascale high-dose case included in the Cumbrian but not the HSE study, (iii) differences between analyses using categorical and continuous PPI dose and (iv) the presence of Seascale controls with PPI over 200 mSv in the Cumbrian but not the HSE study. 相似文献
990.
Mother's education and perinatal problems in Finland. 总被引:5,自引:0,他引:5
E Hemminki J Meril?inen M Malin O Rahkonen J Teperi 《International journal of epidemiology》1992,21(4):720-724
This study using nationwide data expands a previous study from one area in Finland. The purpose was to study how perinatal problems (mortality, short gestation, low birthweight and low Apgar scores) vary by mother's social class, which is measured by level of education. Outcomes of all births in the 1987 Medical Birth Register were linked to the 1988 National Education Register with gives the estimated number of years of completed education. In unadjusted analyses, the lowest educational groups (less than 9 years) had the worst results for outcomes other than neonatal mortality. Results in the two highest educational groups (greater than or equal to 13 and 12 years of education) were similar and if anything, better in the second highest group. Excluding twins and adjusting for confounding variables (age, parity, county, urbanization of residence) by logistic regression analysis did not alter the results much. Adjustment for possible mechanisms correlated with social class (marital status, smoking, time of first antenatal visit) decreased the higher occurrence of low birthweight infants in the low educational groups. Reported previous miscarriages were more common in the higher educational groups. Based on the available background characteristics one would expect to have found the usual social gradient in perinatal problems to have persisted between the two highest educational groups. Further studies on factors causing the plateau in the gradient between these groups might be useful. 相似文献