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排序方式: 共有693条查询结果,搜索用时 31 毫秒
1.
J T Knuiman J G Hautvast K F Zwiauer K Widhalm M Desmet G De Backer R R Rahneva V S Petrova M Dahl J Viikari 《European journal of clinical nutrition》1988,42(10):847-855
We have measured systolic and diastolic blood pressure and excretions of sodium, potassium, calcium and magnesium in groups of about 50 8- and 9-year-old boys from 19 European centres using standardized methods for the measurement of blood pressure and collection of urine, and by carrying out all analyses in one laboratory. Weight, height, pulse rate and environmental temperature were also studied. Mean systolic blood pressure ranged from 91 to 105 mm Hg and diastolic blood pressure from 51 to 66 mm Hg. Mean 24-h excretion of sodium was between 91 and 146 mmol/d, that of potassium between 29 and 60 mmol/d, that of calcium between 1.5 and 2.6 mmol/d and that of magnesium between 2.7 and 4.2 mmol/d. Mean sodium excretion tended to be lower and potassium excretion tended to be higher in the boys from the north-western parts of Europe. Relations between either systolic or diastolic blood pressure and electrolyte excretions were generally weak or absent. Most remarkable is that only the association between mean diastolic blood pressure and 24-h magnesium excretion (partial regression coefficient (b +/- s.e., -5.04 +/- 2.08 mm Hg/mmol/d) was statistically significant after adjusting for differences in creatinine excretion and environmental temperature. Mean systolic blood pressure was not significantly related with any of the variables measured. The partial regression coefficient (b +/- s.e.) for diastolic blood pressure on weight was 0.186 +/- 0.062 mm Hg/kg, on height 0.165 +/- 0.056 mm Hg/cm, on pulse rate 0.364 +/- 0.100 mm Hg/beats per min and on outside temperature -0.25 +/- 0.07 mm Hg/degrees C. 相似文献
2.
Using antibodies directed to beta 2-microglobulin (b2-m) and HLADR antigens, the expression of MHC products by normal and abnormal bile ducts in 90 paraffin-embedded biopsies showing various liver diseases, was studied. Normal and abnormal bile ducts constantly expressed b2-m. Increased b2-m expression was found in 17/19 PBC, and 4/7 chronic aggressive hepatitis or cirrhosis of viral etiology with hepatitic bile duct lesions. Normal bile ducts failed to express HLADR antigens. Aberrant HLADR display was found in 24/26 PBC and 10/16 chronic aggressive hepatitis or cirrhosis of viral etiology with hepatitic bile duct lesions. It is concluded that the pattern of the major histocompatibility complex (MHC) display does not discriminate between PBC and hepatitic bile duct lesions. Enhanced expression of class I MHC products at the surface of medium-sized bile ducts in PBC may render these structures more susceptible to lysis by cytotoxic T-cells, whereas its significance in chronic aggressive hepatitis or cirrhosis remains unknown. Aberrant expression of HLADR antigens by abnormal bile ducts in PBC and chronic aggressive hepatitis or cirrhosis of viral etiology is probably induced by gamma-interferon, liberated by intra-epithelial lymphocytes, and may serve to enhance the immune response, either by attracting HLADR-restricted cytotoxic T-cells or by the presentation of non-self antigens at the surface of bile duct epithelium. 相似文献
3.
F. Facchetti Chris de Wolf-Peeters J. J. van den Oord C. J. L. M. Meijer S. T. Pals V. J. Desmet 《Immunology letters》1989,20(4):277-281
So-called plasmacytoid T cells represent a subset of monocyte related cells, which share with endothelium the CD36+CD11b− (OKM5+OKM1−) phenotype. The reactivity of plasmacytoid T cells with rat monoclonal antibody HECA-452, highly specific for high endothelial venules, was analyzed in reactive lymph nodes. In all cases, HECA-452 not only labelled the endothelium of high endothelial venules, but also strongly reacted with singular and clustered plasmacytoid T cells. The HECA-452 positivity for high endothelial venules and plasmacytoid T cells visualized a lymph node compartment extending from the subcapsular sinus to the corticomedullary junction. This compartment surrounded the composite nodule and was designated the ”extranodular“ compartment. The cooccurrence of plasmacytoid T cells and high endothelial venules in this extranodular compartment, together with their immunophenotypical similarities, may be indicative of functional co-operations. 相似文献
4.
Cassiman D van Pelt J De Vos R Van Lommel F Desmet V Yap SH Roskams T 《The American journal of pathology》1999,155(6):1831-1839
Synaptophysin is a protein involved in neurotransmitter exocytosis and is a neuroendocrine marker. We studied synaptophysin immunohistochemical expression in 35 human liver specimens (normal and different pathological conditions), in rat models of galactosamine hepatitis and carbon tetrachloride-induced cirrhosis, and in freshly isolated rat stellate cells. Synaptophysin reactivity was present in perisinusoidal stellate cells in both human and rat normal liver biopsies. The number of synaptophysin-reactive perisinusoidal cells increased in pathological conditions. Double staining for alpha-smooth muscle actin and synaptophysin, detected by confocal laser scanning microscopy, unequivocally demonstrated colocalization of both markers in lobular stellate cells. In addition, freshly isolated rat stellate cells expressed synaptophysin mRNA (detected by polymerase chain reaction) and protein. Finally, electron microscopy showed the presence of small electron translucent vesicles, comparable to the synaptophysin-reactive synaptic vesicles in neurons, in stellate cell projections. We conclude that synaptophysin is a novel marker for quiescent as well as activated hepatic stellate cells. Together with the stellate cell's expression of neural cell adhesion molecule, glial fibrillary acidic protein, and nestin, this finding raises questions about its embryonic origin and its differentiation. In addition, the presence of synaptic vesicles in stellate cell processes suggests a hitherto unknown mechanism of interaction with neighboring cells. 相似文献
5.
Nodular alteration of the paracortical area. An in situ immunohistochemical analysis of primary, secondary, and tertiary T-nodules. 总被引:2,自引:1,他引:2
J. J. van den Oord C. De Wolf-Peeters V. J. Desmet K. Takahashi Y. Ohtsuki T. Akagi 《The American journal of pathology》1985,120(1):55-66
With the use of in situ immunohistochemical techniques on freshly frozen and paraffin-embedded material from 63 reactive lymph nodes, the cellular composition of T-nodules observed in 30 cases with nodular alteration of the paracortical area was analyzed. T-nodules were composed of S-100 beta + interdigitating reticulum cells (IDRCs), variable numbers of OKT6+ dendritic cells (DCs), high endothelial venules, and a very high T helper/T suppressor ratio because of an enrichment of OKT4+, Leu3a+ helper/inducer T cells in these nodules. According to their localization in the paracortical area, and the arrangement of IDRCs and high endothelial venules, T-nodules could be divided into "primary" and "secondary" T nodules. In all cases of dermatopathic lymphadenitis, very large aggregates of S-100 beta + and OKT6+ DCs, admixed with few high endothelial venules and variable numbers of OKT4+, Leu3a+ helper/inducer T cells, were observed and were termed "tertiary T-nodules." It is suggested that T-nodules represent the paracortical counterparts of B-lymphoid follicles and are the in vivo equivalents of DC/T-cell clusters observed in vitro. According to their cellular composition and localization in the lymph node, "primary" and "secondary" T-nodules probably represent subsequent maturation stages of distinctive nodular paracortical structures, which play an important role in the presentation of antigens to helper/inducer T cells and in the proliferation of antigen-responsive T cells. Their close topographic relationship to B-lymphoid follicles may indicate their role in the extrafollicular generation of antibody-forming cells. 相似文献
6.
J J van den Oord C De Wolf-Peeters G Tricot V J Desmet 《American journal of clinical pathology》1984,82(4):491-495
A series of monoclonal and polyclonal antibodies was used to determine the distribution of lymphocyte subsets in frozen tissue sections of a case of angiofollicular lymph node hyperplasia (ALNH), intermediate type. Primary follicles and mantle zones of secondary follicles consisted of BA1+OKIa1+-C3RTo5+sIgM+sIgD+ lymphocytes. Poorly developed follicular centers reacted with OKIa1, C3RTo5, DRC-1 and anti-IgM but contained no OKT4+Leu-3a+ or Leu-7+ cells. Mantle zones and primary follicles contained more OKT4+Leu-3a+ and less OKT8+ cells than normally observed. The interfollicular area consisted mainly of OKT4+Leu-3a+OKIa1- helper/inducer T-cells, admixed with some OKT8+ suppressor/cytotoxic T-cells and OKIa1+ interdigitating reticulum cells. Polyclonal plasma cells were found both in follicular centers and interfollicular areas. Based on the analogy to the peripheral lymphoid tissue in nude mice and in children with variable thymic dysfunction, it is suggested that the abnormal distribution of immunoregulatory T-cells may be of pathogenetic significance and may account for the morphology of the lymphoid follicles in ALNH. 相似文献
7.
M. Willems L. Sheng T. Roskams B. Ramdani J. M. Doutrelepont F. Nevens P. Durez S. Treille M. Adler V. Desmet J. Fevery S. H. Yap 《Journal of medical virology》1994,44(3):266-271
Recently, evidence has been presented for a possible association between hepatitis C virus (HCV) infection and essential mixed cryoglobulinemia (EMC). Eleven consecutive patients with EMC and two with cryoglobulinemia type I were examined for the presence of markers of HCV infection. Eleven of 13 patients (10 with EMC and 1 with type I cryoglobulinemia) had anti-HCV antibodies (as determined by a second generation anti-HCV assay) and HCV-RNA in plasma or serum. HCV-RNA was also detected in liver biopsies of five patients. Genotyping showed that HCV genotype 1 was found in 10 of 11 patients with HCV-RNA (9 genotype 1b and 1 genotype 1a) and only one patient had HCV genotype 2. However, a similar high prevalence of genotype 1b (100%) was found in a group of 14 consecutive patients with chronic hepatitis C, who had no clinical evidence of cryoglobulinemia. Concomitant infection was present in three patients with genotypes 2, 3 and 4, respectively. These findings stress the high prevalence of HCV infection in patients with EMC and further study shows that a difference in genotype prevalence was not found between HCV-related EMC and chronic hepatitis C without clinical manifestations of EMC. © 1994 Wiley-Liss, Inc. 相似文献
8.
In the human embryo, the first anlage of the bile ducts and the liver is the hepatic diverticulum or liver bud. For up to 8 weeks of gestation, the extrahepatic biliary tree develops through lengthening of the caudal part of the hepatic diverticulum. This structure is patent from the beginning and remains patent and in continuity with the developing liver at all stages. The hepatic duct (ductus hepaticus) develops from the cranial part (pars hepatica) of the hepatic diverticulum. The distal portions of the right and left hepatic ducts develop from the extrahepatic ducts and are clearly defined tubular structures by 12 weeks of gestation. The proximal portions of the main hilar ducts derive from the first intrahepatic ductal plates. The extrahepatic bile ducts and the developing intrahepatic biliary tree maintain luminal continuity from the very start of organogenesis throughout further development, contradicting a previous study in the mouse suggesting that the extrahepatic bile duct system develops independently from the intrahepatic biliary tree and that the systems are initially discontinuous but join up later. The normal development of intrahepatic bile ducts requires finely timed and precisely tuned epithelial–mesenchymal interactions, which proceed from the hilum of the liver toward its periphery along the branches of the developing portal vein. Lack of remodeling of the ductal plate results in the persistence of an excess of embryonic bile duct structures remaining in their primitive ductal plate configuration. This abnormality has been termed the ductal plate malformation. Anat Rec, 291:628–635, 2008. © 2008 Wiley‐Liss, Inc. 相似文献
9.
Paul De Sutter Dmitri Dozortsev Philippe Vrijens Rita Desmet Marc Dhont 《Journal of assisted reproduction and genetics》1994,11(8):382-388
Purpose
Treatment of aged human oocytes by puromycin allows a high rate of parthenogenetic activation and development until the first cleavage division. This technique was used for the study of the chromosome complement of oocytes which remained unfertilized after in vitro fertilization. Three hundred four unfertilized oocytes were treated with 10 Μg/ml puromycin for 6–8 hr and further cultured for 12–15 hr.Results
Activation occurred in 90.5% of the oocytes. Heterozygous diploids with two pronuclei predominated (61%), which is in contrast to the mouse, where the majority of oocytes activated by puromycin are uniform haploids (89%).Conclusions
Therefore we conclude that puromycin treatment induces retention of the second polar body in human oocytes, unlike in mouse oocytes treated in the same way. Chromosome analysis performed on 182 oocytes suggested a nondisjunction (ND) rate for the second meiotic division of 12.7%. This is a low figure considering the fact that puromycin itself has been reported to induce nondisjunction. For the first meiotic division a ND rate of only 5.6% was found. This rate is lower than the one found in metaphase II arrested oocytes and we believe that this difference is due to the technical differences between the study of meiotic and that of mitotic chromosomes. 相似文献10.
Histologic appearances of endoscopic gastric mucosal biopsies 10--20 years after partial gastrectomy. 总被引:2,自引:0,他引:2 下载免费PDF全文
Fifty-six symptomatic patients, who had had a partial gastrectomy 10--24 years previously for benign disease, were examined by endoscopy and multiple mucosal biopsies. No patient had a completely normal gastric mucosa. Varying degrees of gastritis, intestinal metaplasia, foveolar hyperplasia and dysplasia were seen. Seventeen patients (30%) had extensive areas of dysplasia associated with acute or chronic inflammation. Severe dysplasis, however, was detected in only one case. In five patients a "diffuse type" carcinoma of the gastric stump was found. While it is generally accepted that significant dysplasia (moderate or severe dysplasis) is premalignant, the degree of risk is unknown. This makes management of individual patients difficult. 相似文献