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981.
A 40-year-old man with epidermodysplasia verruciformis showed a decrease in peripheral blood T cells and abnormal expansion of large granular lymphocytes, accompanied by increased natural killer cell activity. Surface marker analysis of his large granular lymphocytes demonstrated that the subset, CD 57+ and CD 16+, had increased. His father, who had no skin lesions of epidermodysplasia verruciformis, displayed similar blood changes and his brother showed a decrease in T cells and a slight increase in CD 16+ natural killer cells, whereas his mother revealed only a slight decrease in T cells. Our present study indicates that epidermodysplasia verruciformis might be associated with hereditary abnormal expansion of large granular lymphocytes and a decrease in T cells. 相似文献
982.
T Nakagawa S Konno T Maemura K Goto Y Hayashibe T Yoshida 《Canadian Metallurgical Quarterly》1993,41(11):2245-2249
A 45-year-old woman with atrial septal defect and pulmonary hypertension was admitted for surgical repair. Cardiac catheterization data revealed pulmonary to systemic flow ratio (Qp/Qs) of 1.81, pulmonary artery pressure (PAP) of 82/30 mmHg and pulmonary vascular resistance (PVR) of 10.8 unit. Open lung biopsy was added to evaluate pulmonary vascular obstructive disease (PVOD) which was shown Heath-Edwards grade 3 PVOD. Following closure of the defect, PAP (systolic) exceeded momentarily systemic level after cardiopulmonary bypass. Prostaglandin E1 drip was remarkably effective to bring down PAP during early postoperative period. Although PAP has not been shown significant decrease on catheterization of one year after surgery, great symptomatic improvement has been achieved. 相似文献
983.
T Hiroshima A Higashi T Imamoto S Kusumoto K Itakura K Nishijima K Nishi 《Canadian Metallurgical Quarterly》1996,116(12):951-960
We investigated whether a chemical assay by high-performance liquid chromatography (HPLC) as an alternative to the complicated and time-consuming bioassay for CS23 mutein of recombinant human basic fibroblast growth factor (rhbFGF-CS23) using the fetal bovine heart endothelial cell line ATCC CRL 1395. Physically, chemically or enzymatically denatured rhbFGF-CS23 was subjected to heparin affinity (HA)-HPLC and the bioassay. Good agreement was observed between the results obtained by these two methods. Moreover, HA-HPLC gave much more reproducible results (RSD = 1.9%, n = 6) than the bioassay (RSD = 7.4%, n = 18). HA-HPLC is therefore a simple, accurate and reproducible alternative to the bioassay for quality control and stability studies for rhbFGF-CS23 preparations. HA-HPLC is also considered to be applicable to assays for FGFs which have heparin affinity and biological activity similar to those of the CS23 mutein. 相似文献
984.
The effect of a weld line on the tensile, tensile impact and environmental stress cracking properties of a number of polyethylene (PE) and polypropylene (PP) samples has been investigated. The observed mechanical behaviour has been correlated to material properties, and also to the weld line morphology. PE samples differed in branching, molar mass (Mw) and molar mass distribution (MWD), whereas the PP samples differed in nucleation. The morphology of the weld line formed in injection moulding was analysed by optical microscopy and transmission electron microscopy. The mechanical strength was studied by tensile, tensile impact and constant tensile stress methods. In polyethylene samples with a high Mw, the weld line area was seen through the skin layer to the shear layer, and even down to the beginning of the core layer. The effect of a high Mw on morphological changes was diminished by a broad MWD. Short chain branching limited the morphological change solely to the skin layer. Both PP samples were morphologically rather homogeneous. The weld line created a V-notch on the surface that acted as a crack initiator in mechanical tests and thus reduced the mechanical strength of the weld line samples. The V-notch mainly hid the effect of the morphology on the mechanical properties. © 1998 Chapman & Hall 相似文献
985.
V Robert F De Giorgi ML Massimino M Cantini T Pozzan 《Canadian Metallurgical Quarterly》1998,273(46):30372-30378
Direct monitoring of the free Ca2+ concentration in the sarcoplasmic reticulum (SR) was carried out in rat skeletal myotubes transfected with a specifically targeted aequorin chimera (srAEQ). Myotubes were also transfected with a chimeric aequorin (erAEQ) that we have demonstrated previously is retained in the endoplasmic reticulum (ER). Immunolocalization analysis showed that although both recombinant proteins are distributed in an endomembrane network identifiable with immature SR, the erAEQ protein was retained also in the perinuclear membrane. The difficulty of measuring [Ca2+] in 100-1000 microM range was overcome with the use of the synthetic coelenterazine analogue, coelenterazine n. We demonstrate that the steady state levels of [Ca2+] measured with srAEQ is around 300 microM, whereas that measured with erAEQ is significantly lower, i.e. around 200 microM. The effects of caffeine, high KCl, and nicotinic receptor stimulation, in the presence or absence of external calcium or after blockade of the Ca-ATPase, were investigated with both chimeras. The kinetics of [Ca2+] changes revealed by the erAEQ were similar, but not identical, neither quantitatively nor qualitatively, to those monitored with the srAEQ, indicating that at this stage of muscle development, differences exist between SR and ER in their mechanisms of Ca2+ handling. The functional implications of these findings are discussed. 相似文献
986.
J Langhorne C Cross E Seixas C Li T von der Weid 《Canadian Metallurgical Quarterly》1998,95(4):1730-1734
B cell knockout mice are unable to clear a primary erythrocytic infection of Plasmodium chabaudi chabaudi. However, the early acute infection is controlled to some extent, giving rise to a chronic relapsing parasitemia that can be reduced either by drug treatment or by adoptive transfer of B cells. Similar to mice rendered B-cell deficient by lifelong treatment with anti-mu antibodies, B cell knockout mice (muMT) retain a predominant CD4+ Th1-like response to malarial antigens throughout a primary infection. This contrasts with the response seen in control C57BL/6 mice in which the CD4+ T-cell response has switched to that characteristic of Th2 cells at the later stages of infection, manifesting efficient help for specific antibodies in vitro and interleukin 4 production. Both chloroquine and adoptive transfer of immune B cells reduced parasite load. However, the adoptive transfer of B cells resulted in a Th2 response in recipient muMT mice, as indicated by a relative increase in the precursor frequency of helper cells for antibody production. These data support the idea that B cells play a role in the regulation of CD4+ T subset responses. 相似文献
987.
K Jin-no M Tanimizu I Hyodo Y Nishikawa Y Hosokawa H Endo T Doi K Mandai H Ishitsuka 《Canadian Metallurgical Quarterly》1998,82(7):1260-1267
BACKGROUND: Platelet-derived endothelial cell growth factor (PD-ECGF) is an angiogenic factor that is expressed in various cancer tissues. Little is known regarding plasma PD-ECGF levels in patients with chronic liver disease such as chronic hepatitis (CH), cirrhosis, and hepatocellular carcinoma (HCC) with cirrhosis. The expression of PD-ECGF in HCC tissues also remains to be clarified. METHODS: Plasma PD-ECGF levels in patients with chronic liver disease were determined with an enzyme-linked immunoadsorbent assay system using the mouse monoclonal antibodies specific to PD-ECGF. These were cross-sectionally compared among groups of normal persons, CH, cirrhosis, and HCC patients. The HCC patients were classified into two groups based on TNM stage: early and advanced stage disease groups. PD-ECGF expressions in HCC tissues were immunohistologically examined. RESULTS: The plasma PD-ECGF levels from the normal individuals and those with CH, cirrhosis, and HCC specimens were 4.2+/-0.5, 4.3+/-0.6, 4.6+/-1.1, and 6.0 +/-2.5 U/mL, respectively. The plasma PD-ECGF concentration was highest in HCC (P < 0.05). No significant difference was found among the normal subjects, CH, and cirrhosis specimens. Plasma PD-ECGF concentrations were significantly higher in the advanced stage disease HCC group compared with the early stage disease group (6.75+/-2.62 U/mL vs. 4.19+/-0.34 U/mL) (P < 0.05). Immunohistochemical expression of PD-ECGF in HCC cells increased significantly compared with normal liver cells (P < 0.05). CONCLUSIONS: Circulating PD-ECGF plasma level might be a new tumor marker for progression in patients with HCC. Immunohistological findings correspond to elevation of the plasma PD-ECGF in HCC patients. It is possible that increased production of PD-ECGF in HCC cells causes abundant neovascularization. 相似文献
988.
C Sergi K Jundt S Seipp T Goeser L Theilmann G Otto HF Otto WJ Hofmann 《Canadian Metallurgical Quarterly》1998,29(6):861-871
BACKGROUND/AIMS: The aim of the study was to assess the impact factor of HCV and HGV in fulminant hepatic failure. METHODS: The 5'-untranslated regions of HCV RNA and HGV RNA and a segment of the core antigen sequence of HBV were amplified after extracting the nucleic acids from snap-frozen tissue aliquots from explanted livers of 26 consecutive patients undergoing orthotopic liver transplantation for fulminant hepatic failure preoperatively diagnosed as either autoimmune (n=2), HAV/HBV (n=8), toxic (n=4) or aetiologically unknown (n=12). RESULTS: HCV RNA was detected in five of 26 (19.2%) livers with fulminant hepatic failure. All five HCV RNA-positive livers belonged to the group of non-toxic, non-autoimmune liver failure (n=20), three of them were found in the group of liver failure with unknown aetiology (n=12) and two in the group of HBV-associated liver failure (n=7), making an HCV incidence of 25%, 25% and 28.6%, in the different groups, respectively. HGV RNA was detected in 10 of 17 (58.8%) explants and in all four groups of fulminant hepatic failure as defined preoperatively. HBV DNA was identified in six livers of 26 patients (23.1%) with fulminant hepatic failure. Neither HCV RNA nor HBV DNA was detected in the livers of patients with toxic or autoimmune fulminant hepatic failure. CONCLUSIONS: These results indicate that HBV and HCV, but not HGV, play an aetiologic role in fulminant hepatic failure. HCV-positive cases were concentrated either in the group of otherwise unexplained fulminant hepatic failure or in the group of HBV fulminant hepatic failure. HGV-positive cases, on the other hand, were found within all four preoperatively defined groups, indicating a role as cofactor rather than as single aetiologic agent. 相似文献
989.
J Oldenhof R Vickery M Anafi J Oak A Ray O Schoots T Pawson M von Zastrow HH Van Tol 《Canadian Metallurgical Quarterly》1998,37(45):15726-15736
The dopamine D4 receptor is a G protein-coupled receptor (GPCR) that belongs to the dopamine D2-like receptor family. Functionally, the D2-like receptors are characterized by their ability to inhibit adenylyl cyclase. The dopamine D4 receptor as well as many other catecholaminergic receptors contain several putative SH3 binding domains. Most of these sites in the D4 receptor are located in a polymorphic repeat sequence and flanking sequences in the third intracellular loop. Here we demonstrate that this region of the D4 receptor can interact with a large variety of SH3 domains of different origin. The strongest interactions were seen with the SH2-SH3 adapter proteins Grb2 and Nck. The repeat sequence itself is not essential in this interaction. The data presented indicate that the different SH3 domains in the adapter proteins interact in a cooperative fashion with two distinct sites immediately upstream and downstream from the repeat sequence. Removal of all the putative SH3 binding domains in the third intracellular loop of the dopamine D4 receptor resulted in a receptor that could still bind spiperone and dopamine. Dopamine could not modulate the coupling of these mutant receptors to adenylyl cyclase and MAPK, although dopamine modulated receptor-G protein interaction appeared normal. The receptor deletion mutants show strong constitutive internalization that may account for the deficiency in functional activation of second messengers. The data indicates that the D4 receptor contains SH3 binding sites and that these sites fall within a region involved in the control of receptor internalization. 相似文献
990.
H Ota T Katsuyama S Nakajima H El-Zimaity JG Kim DY Graham RM Genta 《Canadian Metallurgical Quarterly》1998,29(8):846-850
Helicobacter pylori seem to avoid areas of intestinal metaplasia in the gastric mucosa, but attachment of these bacteria to epithelium with the appearance of incomplete intestinal metaplasia has been documented. To characterize the nature of the epithelium to which H pylori was attached, we carried out an immunohistochemical study using monoclonal antibodies against gastric surface mucous cell mucins (M1), blood group-related carbohydrates antigens (Le(a), sialyl Le(a), Le(b), type 1H, and type 2H) and sialyl Tn antigen. The results of this study suggest that these areas of H pylori attachment represent a hybrid epithelium whose cells share characteristics of both gastric surface mucous cells and intestinal metaplastic cells. Whether all areas of incomplete intestinal metaplasia represent an intermediate stage between the normal gastric epithelium and the fully developed complete type of metaplasia remains to be determined. 相似文献