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71.
Masaki Hata Akinori Nango Hisateru Niki Yoshifumi Hayafune Atsushi Kato 《Journal of orthopaedic science》1997,2(1):3-9
To elucidate the growth of the tarsal bones in congenital clubfoot, relative to the growth of these bones in the unaffected feet and compared to growth in the feet of normal volunteers, we used a computed tomography (CT) scanner to measure the volume of all tarsal bones. The subjects of the study were 10 adults (7 men and 3 women) with unilateral congenital clubfoot (average age 20 years and 1 month). As controls, we examined 11 healthy volunteers. We calculated the ratio of the volume of each tarsal bone to the total bone volume and the ratio of the volume of each tarsal bone in clubfoot to the corresponding bone in the unaffected foot. The volume ratio of each tarsal bone was compared between clubfeet and unaffected feet because the differences of each tarsal bone ratio between the normal foot group and unaffected foot group were not significant. In the clubfeet (n=10), the talus and the medial cuneiform bones were smaller than those in the unaffected feet (n=10) but the cuboid bone was larger. The growth of the navicular did not differ from as that in unaffected feet. Our results suggested hypoplasia on the medial side of the foot in adult patients with congenital clubfoot. The 3 patients who had undergone medial release showed particularly marked hypoplasia of the medial side. In congenital clubfoot cases with severe deformities who had undergone wide soft-tissue release operations, there were clear growth suppressions in the talus and the medial cuneiform. We could not determine whether the cause of the growth suppression was the hypoplastic nature of tarsal bones themselves or the surgical obstacles to tarsal bone growth. 相似文献
72.
G. W. McCAUGHAN C-L. SIAH C. ABBOTT J. WICKSON M. BALLESTEROS G. A. BISHOP 《Journal of gastroenterology and hepatology》1993,8(2):142-145
Dipeptidyl peptidase IV (DPP-IV) is a cell surface ectopeptidase that has been implicated in cell-extracellular matrix interactions, lymphocyte growth and the regulation of biological peptides. Previous studies have shown that immunostaining for DPP-IV and DPP-IV enzyme levels is decreased in hepatoma cells and levels have been correlated with the ability of such cells to adhere in vitro. The aim of this paper was to measure DPP-IV enzyme levels in rat hepatoma cells and to examine whether changes were associated with alterations at the mRNA level. The results indicate a greater than 90% reduction in DPP-IV enzyme levels in two rat hepatoma cell lines, HTC and H35, compared with rat hepatocytes. Enzyme levels of the control enzyme leucine aminopeptidase (LAP) were not decreased. mRNA studies indicated that these changes were associated with similar reductions in rat DPP-IV mRNA. It is concluded that DPP-IV is markedly reduced at the protein, enzyme and mRNA levels in rat hepatoma cells. The significance of these changes is unclear but may lead to decreased extracellular matrix interactions by such cells. 相似文献
73.
C. L. R. BARRATT P. E. HARRISON A. ROBINSON I. D. COOKE 《International journal of andrology》1990,13(1):50-58
The significance of white blood cells in the ejaculate remains a matter of controversy. Several authors have suggested that such cells are important in the modulation of an antisperm antibody response, i.e. a predominance of suppressor/cytotoxic to helper/inducer T cells may prevent the development of antisperm antibodies. In order to examine this relationship further we have documented the white blood cell types, with emphasis on the T-lymphocyte populations, in the ejaculates of men from infertile couples with and without antisperm antibodies; the latter group was divided further into two groups--vasovasostomized men and idiopathic men. All seven of the men without antisperm antibodies had a predominance of suppressor/cytotoxic T cells to helper/inducer T cells in the ejaculate. However, only in some of the men with antibodies was there a predominance of T-helper/inducer cells. It is clear that the relationship between antisperm antibodies and seminal leucocytes is therefore not as straightforward as has been proposed. 相似文献
74.
Katalin Vehmeyer Tibor Hajto Katarina Hostanska Stefan Knemann Holger Lser Reinhard Saller Bernhard Wrmann 《European journal of haematology》1998,60(1):16-20
Abstract: The galactoside-specific plant lectin, Viscum album agglutinin (VAA-I) increases cellular parameters of natural host defence. It also binds to a variety of haematopoietic cells, including progenitors. We investigated whether VAA-I has a stimulatory effect on haematopoietic progenitor cells. Peripheral blood progenitor cells from 7 healthy volunteers were cultured in a colony assay with VAA-I plus erythropoietin (EPO) and stem cell factor (SCF). At 50 pg/ml VAA-I induced a significant increase in the cytokine-dependent clonogenic growth (52% in median, p<0.05). In another set of experiments purified CD34+ cells were isolated from the bone marrow aspirate of 4 patients with non-metastatic breast cancer using fluorescence-activated cell sorting. Binding to CD34+ cells was demonstrated by using directly fluorescence-conjugated VAA-I. Co-incubation with d -galactose significantly abrogated this effect. CD34+ cells were cultured in the presence of EPO, SCF, interleukin-3, granulocyte/monocyte colony-stimulating factor and granulocyte colony-stimulating factor. VAA-I alone had no measurable effect on the clonogenic growth of the isolated cells. However, at concentrations of 100 and 250 pg/ml VAA-I increased the cytokine-dependent proliferation and differentiation of CD34+ cells by a median of 75 and 85%, respectively. The results show that VAA-I binds to haematopoietic progenitor cells and has a co-stimulatory effect on their proliferation. 相似文献
75.
用限制性内切酶EcoRI从pKS(-)HTH_1切下全长为1.9 kb的人酪氨酸羟化酶基因,在T_4DNA连接酶的作用下连接在真核表达载体pCDNA_3的EcoR Ⅰ位点,构建成重组质粒pcD-NA_3HTH_1,该质粒转染COS-7细胞,免疫荧光组织化学染色证实酪氨酸羟化酶在其中的表达。 相似文献
76.
Klaus Edvardsen Nils Brünner Mogens Spang-Thomsen Frank S. Walsh Elisabeth Bock 《International journal of developmental neuroscience》1993,11(5)
A cDNA encoding a transmembrane 140 kDa isoform of the neural cell adhesion molecule, NCAM, was transfected into the rat glioma cell line BT4Cn. Transfectants with a homogeneously high expression of NCAM-B showed a decreased capacity for penetration of an artificial basement membrane when compared to cells transfected with expression-vector alone or untransfected cells. However, when injected subcutaneously into nude mice, both NCAM expressing cells and control cells produced invasive tumors. Nude mice injected with NCAM positive cells developed tumors with slower growth rates as compared to those induced by NCAM negative cells. This implies that NCAM may not only be involved in adhesive and motile behaviour of glioma cells, but also in their growth regulation. 相似文献
77.
Abstract A case of external inflammatory root resorption and labial fenestration in a maxillary central incisor is presented. The root canal was dressed with pure calcium hydroxide mixed with normal saline for 1 month before it was obturated with gutta percha and apicoectomy surgery undertaken to attempt primary closure of the fenestration. The PDL and the fenestration healed uneventfully. 相似文献
78.
Eileen J. Martin Kiran S. Panickar Michael A. King Malgorzata Deyrup Bruce E. Hunter Geehuan Wang Edwin M. Meyer 《Drug development research》1994,31(2):135-141
The potential cytoprotective actions of a novel nicotinic agent 2,4-dimethoxybenzilidene anabaseine (DMXB) were investigated in differentiated PC12 cells and transected rat septal cholinergic neurons in vivo. In NGF-differentiated PC12 cells, removal of both NGF and serum led to cell loss, a reduced % of cells expressing neurites, the release of lactate dehydrogenase, and a decrease in total cellular protein. Cell loss was apparent within 24 h, and remained constant between 4–8 days post-NGF removal. NGF alone (100 ng/ml), DMXB (10 μM), but not nicotine (10 μM), prevented these cell and neurite losses. DMXB-induced cytoprotection was blocked by 1 μM mecamylamine. DMXB (1 mg/kg, ip) injected twice but not once per day protected cholinesterase-staining septal neurons from retrograde degeneration following unilateral fimbrial transections. The twice per day DMXB injection-protocol also decreased cell roundness among cholinesterase-staining cells in the lesioned septal hemisphere compared to saline-injected animals. These studies suggest that DMXB may exert cytoprotective activity in NGF-sensitive neuronal populations. © 1994 Wiley-Liss, Inc. 相似文献
79.
R C Ayres S G Hübscher J Shaw C Garner R Joplin A Williams J M Neuberger 《The Journal of pathology》1991,165(2):153-161
We have produced a range of monoclonal antibodies which stain human intrahepatic bile ducts of different sizes. Amongst 26 monoclonal antibodies produced, five clones reacted specifically with bile ducts of different sizes, of which three have been maintained in culture and their viability following freezing and thawing confirmed. Staining patterns varied between normal adult liver tissue, normal fetal liver tissue and a variety of hepatobiliary diseases. The antibodies provide further evidence of the immunological heterogeneity of the human intrahepatic biliary tree and support the hypothesis that proliferating bile ductules are derived from periseptal hepatocytes. The preparation of the antibodies, their staining reactions in normal adult, normal fetal and a variety of liver diseases are described. 相似文献
80.