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21.
22.
Molecular cloning of human gastrin cDNA: evidence for evolution of gastrin by gene duplication. 总被引:26,自引:7,他引:19 下载免费PDF全文
E Boel J Vuust F Norris K Norris A Wind J F Rehfeld K A Marcker 《Proceedings of the National Academy of Sciences of the United States of America》1983,80(10):2866-2869
An oligo(dT)-primed cDNA copy of the mRNA coding for the human gastrin precursor was constructed from poly(A)-containing RNA from a human pancreatic, gastrin-producing tumor (a gastrinoma). The cDNA was inserted into the Pst I endonuclease site of plasmid pBR322 by the use of the poly(dC) and poly(dG) tailing procedure. Clones containing gastrin sequences were selected by hybridization to a purified single-stranded 32P-labeled gastrin cDNA probe. This probe was constructed with gastrinoma mRNA as template. As primer for the cDNA synthesis, we used a synthetic oligonucleotide mixture, d(AG-A-A-AG-T-C-C-A-T-C-C-A), corresponding to the gastrin-specific amino acid sequence Trp-Met-Asp-Phe. In this way we determined the nucleotide sequence of the entire coding region (303 nucleotides), the entire 3' untranslated region (102 nucleotides), and 8 nucleotides of the 5' untranslated region. A striking homology between parts of the coding region suggests that evolution of the gastrin gene has involved a gene duplication. 相似文献
23.
Björnberg KA Vahter M Berglund B Niklasson B Blennow M Sandborgh-Englund G 《Environmental health perspectives》2005,113(10):1381-1385
It is well established that methylmercury (MeHg) and mercury vapor pass the placenta, but little is known about infant exposure via breast milk. We measured MeHg and inorganic mercury (I-Hg) in blood of Swedish mothers (n = 20) and their infants, as well as total mercury (T-Hg) in breast milk up to 13 weeks postpartum. Infant blood MeHg was highly associated with maternal blood MeHg at delivery, although more than twice as high. Infant MeHg decreased markedly until 13 weeks of age. Infant blood I-Hg was associated with, and about as high as, maternal blood I-Hg at delivery. Infant I-Hg decreased until 13 weeks. In breast milk, T-Hg decreased significantly from day 4 to 6 weeks after delivery but remained unchanged thereafter. At 13 weeks, T-Hg in breast milk was associated with infant MeHg but not with maternal MeHg. Conversely, T-Hg in breast milk was associated with maternal I-Hg but not with infant I-Hg. From the findings of the present study in which the exposure to both MeHg and I-Hg was low, we conclude that the exposure to both forms of mercury is higher before birth than during the breast-feeding period, and that MeHg seems to contribute more than I-Hg to infant exposure postnatally via breast milk. 相似文献
24.
W. Flameng M.D. F. Schwarz M.D. Prof. Dr. F. Hehrlein M.D. A. Boel 《Basic research in cardiology》1978,73(2):188-199
Summary In 29 patients with coronary artery disease the functional significance of coronary collaterals was studied during surgery for aortocoronary bypass grafting.Poststenotic coronary pressure and postocclusion graft flow hyperemia were measured in 34 vessels receiving a coronary bypass graft. The vessels were divided into groups according to the angiographically determined degree of coronary stenosis: group I: stenosis up to 80%, group II: stenosis between 80 and 90%, group III: stenosis between 90 and 100%, Group IV: acute occlusion without visible collaterals and Group V: complete occlusions with collaterals. When a coronary stenosis surpasses 80% luminal narrowing it becomes hemodynamically significant: pressure gradient over the stenosis becomes significant and there appears a hyperemic response after graft occlusion. From group I to IV poststenotic coronary pressure decreases and graft flow hyperemia increases significantly (p<0.05).In all cases general coronary vasodilation was produced by intracoronary injection of dipyridamole. After vasodilation poststenotic coronary pressure decreased significantly (p<0.05) in groups I and II but not in III and IV. This indicates that there is still some increase in flow over the stenosis i.e. coronary reserve is not completely expended until 90% stenosis. Hyperemic graft flow response correlates well with poststenotic coronary pressure: the relation can be described by an asymptotic regression. This suggests that graft flow hyperemia is a reflection of compensatory peripheral vasodilation rather than a response to ischemia.In group V, i.e. complete chronic occlusions with collaterals, peripheral coronary pressure was 40.7±3.3% of systemic pressure and this value decreased significantly (p=0.002) to 34.0±2.6% after vasodilation. Hyperemic response was 1.57±0.07. These values are significantly different from groups I and IV, but not from II and III.These findings suggest that coronary collaterals restore coronary reserve partially. Nevertheless, a chronic coronary occlusion compensated by collaterals corresponds functionally to a 90% pure stenosis.
With 4 figures and 2 tables 相似文献
Die funktionelle Bedeutung des Kollateralkreislaufes beim Menschen
Zusammenfassung Die Bedeutung des koronaren Kreislaufes wurde an 29 Patienten mit koronarer Herzerkrankung während der aortokoronaren Bypassoperation untersucht. Poststenotischer Koronararteriendruck und Graftfluß vor und 30 sec nach Graftverschluß wurden an 34 Gefäßen, die mit einem aortokoronaren Bypass versorgt wurden, gemessen. Nach dem angiografisch bestimmten Grad der Koronararterienstenose (% Lumeneinengung) wurden folgende Gruppen gebildet: Gruppe I = Stenose bis 80%, Gruppe II = Stenose zwischen 80 und 90%. Gruppe III = Stenose zwischen 90 und 100%, Gruppe IV = akuter Verschluß ohne angiographisch sichtbare Kollateralen und Gruppe V = kompletter Verschluß mit Kollateralen. Wenn eine Koronarstenose 80% Lumeneinengung erreicht, wird sie hämodynamisch bedeutsam, es entsteht ein signifikanter Druckgradient über die Stenose und eine signifikante Hyperämie nach Öffnen des Grafts. Von Gruppe I bis IV fand sich ein signifikanter Abfall des poststenotischen Druckes und ein signifikanter Anstieg des hyperämischen Graftflusses. Maximale koronare Vasodilatation wurde durch Injektion von Dipyridamol in den Graft induziert. Der poststenotische Druck fiel nach Vasodilatation signifikant ab in Gruppe I und II, nicht in III und IV. Dies bedeutet, daß unter 90% Stenose immer noch der Fluß über die Stenose gesteigert werden kann, die Koronar-reserve ist nicht völlig aufgebraucht. Eine signifikante asymptotische Relation besteht zwischen hyperämischem Graftfluß und poststenotischem Druck. Dies weist darauf hin, daß die hyperämische Reaktion nach Graftverschluß ein Maß der poststenotischen Vasodilatation ist und nicht ein Zeichen von Ischämie. In Gruppe V (kompletter Verschluß mit Kollateralen) war der poststenotische Druck 40,7±3,3% des systemischen Druckes, und dieser Wert fiel signifikant auf 34,0±2,6% nach Vasodilation ab. Die Hyperämie nach Öffnen des Grafts betrug 1,57±0,07 des Kontrollflusses. Diese Werte sind signifikant unterschiedlich von Gruppe I und IV, nicht von II und III.Wir schließen daraus, daß koronare Kollateralen die Koronarreserve teilweise wiederherstellen. Ein chronischer Koronarverschluß mit Kollateralen entspricht funktionell einer 90%igen Koronarstenose ohne Kollateralen.
With 4 figures and 2 tables 相似文献
25.
Arnbjörnsson E Backman T Berglund Y Kullendorff CM 《Pediatric surgery international》2005,21(10):797-799
A gastrostomy device is removed from the gastrostoma when no longer needed. The aim of the study was to test the hypothesis
of whether it is possible for the surgeon to decide which stoma has to be closed with a gastroraphy and which to leave for
a spontaneous closure within a reasonable period of time. Out of a cohort of 321 patients, who had been operated with a video-assisted
gastrostomy, we included all the 48 patients having had their gastrostomy button removed. These patients were carefully followed
and the closure of the gastrostoma was registered. According to the institutional routine we waited at least 3 months after
the removal of the gastrostomy device before suggesting to the child’s guardians an operative closure of the stoma. In 26
patients the stoma closed within 3 months, whereas in 22 patients a surgical gastroraphy was performed. We found no differences
between the two groups regarding the patients’ diagnoses, the duration of the gastrostoma use or patient’s age at the time
of removal of the gastrostomy device. This study rejected the hypothesis of predictability of the gastrostoma closure. Thus,
we recommend a routine expectance after the removal of a gastrostomy device for at least 1 month. If no spontaneous closure
occurs, then a gastroraphy should be performed. 相似文献
26.
Beta-chemokines attract and activate T cells and monocytes and have a key role in chronic inflammation. Certain beta-chemokines, such as monocyte chemoattractant protein-1 (MCP-1), have been reported to be upregulated in the idiopathic inflammatory myopathies (IIM). We studied the distribution of beta-chemokine receptors in polymyositis (PM), sporadic inclusion-body myositis (sIBM), dermatomyositis (DM), and control samples. CCR1-5 were localized to blood vessels in all samples. In addition, increased endothelial expression of CCR2A was observed in IIM. Subsets of inflammatory cells, identified as macrophages and T cells, in all three types of IIM expressed CCR2A, CCR2B, CCR3, CCR4, and CCR5. In contrast to an earlier report, we found CCR2B to be the most prominent MCP-1 receptor on inflammatory cells in IIM, especially in PM and sIBM. Strong CCR4 expression was present on myonuclei of regenerating muscle fibers. The prominence of the CCR2 receptors further underlines the importance of the interaction with their ligand MCP-1 in the immunopathogenesis of IIM and puts CCR2B forward as a potential target for future therapeutic intervention. 相似文献
27.
Objective The microscopic study of the various components of joints provide a proper basis for understanding the nature of pathologic lesions to which they are subject and their imaging appearances. This study was designed to correlate MR imaging with a systematic histological study of the normal sacroiliac joint (SIJ), which to our knowledge is not available in the literature.Design and patients Five male cadavers, aged 20 to 45 years, and seven male and seven female volunteers, aged 23 to 44 years, were investigated with oblique transaxial and coronal MR imaging of the SIJs. A variety of sequences including pre- and post-contrast T1 fat-saturated studies in the volunteers were used. Cryosectioning was performed in six SIJs of the five cadavers and compared with the MR images for the microscopic joint anatomy and assessed for the presence of abnormalities resembling those associated with sacroiliitis.Results Throughout the SIJ, the hyaline cartilage of the sacral bone and the proximal third of the hyaline iliac cartilage was strongly attached to the surrounding stabilizing ligaments, forming wide margins of fibrocartilage. In the distal one-third of the joint only, the margins of the iliac joint facet resemble that of a synovial joint, which include an inner capsule with synovial cells. The MR anatomy of the ventral and dorsal aspects of the SIJ was only adequately visualized at oblique transaxial MR imaging. No contrast enhancement occurred in the synovial tissue or in the cartilaginous joint space. The dorsal transition between the proximal 2/3 and distal 1/3 of the cartilaginous joint was at microscopy rich in anatomical and histological variants, including osseous clefts, cartilage and subchondral defects, and vascular connective tissue in the bone marrow. These were all recognized at oblique transaxial MR imaging and in coronal MR sectioning may resemble abnormalities. Otherwise, no erosions, bone marrow abnormalities, bone sclerosis or abnormal contrast enhancement occurred in the normal joints.Conclusions The SIJ should be classified anatomically as a symphysis with some characteristics of a synovial joint being confined to the distal cartilaginous portion at the iliac side. Coronal MR imaging does not allow assessment of normal anatomy, variants or abnormalities of the ventral and dorsal margins of the cartilaginous SIJ. 相似文献
28.
Bergman L Seregard S Nilsson B Lundell G Ringborg U Ragnarsson-Olding B 《Investigative ophthalmology & visual science》2003,44(8):3282-3287
PURPOSE: To investigate the crude and relative survival rates in patients with uveal melanoma in Sweden during the period from 1960 to 1998. METHODS: A population-based national survey revealed 2997 cases of uveal melanoma in the Swedish Cancer Registry. The survival rates were calculated by the Hakulinen life-table method, using relative survival as an estimate for deaths due to uveal melanoma. The excess mortality rates were calculated with confidence intervals for the first 15 years after diagnosis. Multivariate regression analysis was undertaken to evaluate the influence of gender, age, and calendar period on relative survival the first 5 years after diagnosis. The underlying causes of deaths in the patients with uveal melanoma, as found in the Cause of Death Registry were also investigated. RESULTS: Up to December 31, 1998, 2003 patients had died. The 5-year crude survival rate was 60.3% and the relative survival 70.1%. After 10 years, the rates were 42.5% and 59.4%, respectively. Significant excess mortality existed up to 5.5 years after diagnosis. In the multivariate model, younger age (P < 0.001) and later calendar period (P = 0.002), but not gender (P = 0.117), were associated with better relative survival. Deaths due to uveal melanoma were misclassified in the Cause of Death Registry in more than half of the cases. CONCLUSIONS: This study, covering more than 95% of the uveal melanoma cases in the Swedish population revealed an improvement in relative survival rates for patients with uveal melanoma over time and a significant excess mortality up to 5.5 years after diagnosis. 相似文献
29.
Heijl A Leske MC Bengtsson B Bengtsson B Hussein M;Early Manifest Glaucoma Trial Group 《Acta ophthalmologica Scandinavica》2003,81(3):286-293
AIMS: The Early Manifest Glaucoma Trial (EMGT) (316 eligible eyes) has used a new set of criteria to define visual field progression in glaucoma. This paper provides estimates of the amount of visual field worsening required to reach the EMGT definition of definite perimetric progression. METHODS: In the 148 eyes that reached definite progression, we first determined changes between baseline and the time of definite EMGT progression, both for mean deviation (MD) and for number of highly (p < 0.5%) significantly depressed test points in pattern deviation probability maps. Second, we studied whether such changes depended on baseline MD, intraocular pressure (IOP), age and time to progression, all of which are factors that affect the rate of field progression. RESULTS: In eyes reaching progression, the mean change in MD from baseline was -1.93 dB (SE +/- 0.20) and the mean change in number of significant points was +4.85 (SE +/- 0.35). These changes did not show linear dependency on baseline MD, IOP or time to progression. CONCLUSIONS: The average amount of field deterioration needed to reach EMGT visual field progression has been measured and expressed in more conventional units (i.e. a loss of about - 2dB in MD and an increase in about five highly significant points). These estimates will facilitate the clinical interpretation of the results of EMGT. 相似文献
30.