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41.
In our previous study (Nishinaka et al., 1989), a chicken B cell line (HU3R27) deficient in thymidine kinase activity was used as a fusion partner for production of chicken monoclonal antibody. Specific antibody-producing hybridomas were initially obtained, but they soon lost the ability to produce antibody in culture. The present report documents the development of an improved fusion cell line. R27H4, for the production of chicken monoclonal antibody. This cell line was obtained by fusion of HU3R27 cells with spleen cells of immunized chicken. Fusion of R27H4 cells with spleen cells from chicken immunized by keyhole limpet hemocyanin (KLH) resulted in antibody-producing hybridomas. Subcloned hybridomas secreted highly reactive IgG and weakly reactive IgM. Some of the cell lines have been displaying stable antibody secretions for over 6 months. 相似文献
42.
Satoshi Hisano Winnie Chan Kay Latta Richard J Krieg Jr. James CM Chan 《Clinical and experimental nephrology》1997,1(3):179-186
Growth retardation is a major complication in children with uremia. Protein restriction, calorie deficit, metabolic acidosis,
renal osteodystrophy, and endocrinologic disturbances contribute to the growth failure. The effect of these factors on growth
retardation can be attenuated in part by therapy with vitamin D metabolites, adequate nutrition, alkalization, and dialysis.
Linear growth in children with uremia is markedly retarded despite normal or increased levels of circulating serum growth
hormone. An increased growth hormone level in children with uremia is due to normal growth hormone secretion from the pituitary
gland and impaired growth hormone clearance in the kidney. However, the elevated growth hormone level does not lead to a commensurate
rise in serum insulin-like growth factor I (IGF-I); the serum IGF-I level is decreased or normal in relation to the degree
of renal failure. This discrepancy suggests growth hormone resistance in the liver in uremia. Recent molecular techniques
open a new era in studying the gene expression for growth hormone or IGF-I. There is no doubt today that growth hormone treatment
has the beneficial effect of growth promotion in children with uremia, which also suggests endogenous growth hormone resistance
in target organs or target cells in uremia. 相似文献
43.
J Matsuda 《Rinsho byori. The Japanese journal of clinical pathology》1991,39(7):743-747
The present study was undertaken to discuss whether measurement of neopterin (NP) released into blood from monocytes/macrophage following activation of lymphocytes were useful tool to predict development of AIDS after HIV-1 infection. The subjects used for this study were eighty one cases of hemophilia, of whom 47 cases were HIV-1 antibody tested positive. Serum NP concentration (15.0 +/- 13.8 nmol/l) in anti-HIV-1 antibody-positive group was higher than in-negative group (5.7 +/- 3.3 nmol/l) (p less than 0.05), in which there was no case whose serum NP level amounted to more than 20 nmol/l. In anti-HIV-1 antibody-positive group, in which CD4/CD8 lymphocyte ratio was less than 0.4, serum NP level was significantly higher than in the group whose lymphocyte ratio was more than 0.5 (p less than 0.05). This result represents that there is a reverse correlation of NP concentration with the developing level of immunodeficiency. Furthermore, in eight cases who developed AIDS, serum NP levels turned to increase from several months or earlier until in all cases the levels were more than 30 nmol/l. In three cases of five who were dead, serum NP concentration had decreased to death since several months through one year. These findings reveal that measurement of serum NP concentration is correlated with clinical outcome after HIV-1 infection and it is useful as the marker for prediction of AIDS development. Also these findings represent that a parallel application of serum NP assay to CD4 lymphocyte counting, detection of anti-HIV-1 antibody, IgA, beta 2-microglobulin assays can predict the outcome of the HIV-1 infection more precisely. 相似文献
44.
Caporale CM Capasso M Lucani M Gandolfi P De Angelis MV Di Muzio A Caporale V Uncini A . 《Journal of the peripheral nervous system : JPNS》2004,9(2):114-115
Campylobacter jejuni (C. jejunj) infection is the most common antecedent in the axonal variant of Guillain‐Barré syndrome (GBS). Antibodies against nerve gangliosides found in GBS patients recognize cross‐reactive epitopes in the lipopolysaccharide (LPS) of C. jejuni. This led to the molecular mimicry hypothesis of GBS. We immunized eleven rabbits with a LPS extracted from HS:19 C. jejuni strain isolated from a patient with GBS and complete Freund's adjuvant (CFA)(group I). In a second experiment we immunized seven rabbits with LPS, CFA and keyhole limpet hemocyanin (KLH)(group II). All group I rabbits developed high titers of anti‐LPS, anti‐GM1, anti‐GD1b antibodies and lower titers of anti‐GD1a. One rabbit, 50 days after initial inoculation, showed tremor and weakness. All rabbits of group II developed high titres of antiganglioside antibodies and six animals showed weakness 59–113 days after initial inoculation. Two rabbits died. Pathology showed mild to moderate, tendentially grouped, axonal degeneration in sciatic nerves of four out of five animals. Control rabbits of group I (immunized with CFA only) did not develop antibodies, controls of group II (immunized with CFA + KLH) developed low titers of IgG anti‐GM1. None developed neurological signs or showed axonal degeneration. C. jejuni LPS is a potent B‐cell stimulator capable to induce a strong antiganglioside response in rabbits. However, to induce the neuropathy is crucial to employ KLH, a glycoprotein known to stimulate both humoral and cellular responses. This animal model reproduces the pathogenetic process hypothesized in axonal GBS with antiganglioside antibodies post C. jejuni infection. 相似文献
45.
To clarify the pathophysiology of intermittent claudication in 37 patients with lumbar spinal stenosis, neural function was evaluated by examining somatosensory evoked potentials (stress-SEPs), and nerve action potentials (stress-NAPs) before and after walking stress. It was shown preoperatively that the stress-SEPs became abnormal immediately after walking in 31 of 37 patients. In seven of nine operated patients, the assessment clearly shows that SEPs had reverted to normal after surgery. The present method is noninvasive, simple in technique, painless, and safe, a procedure therefore that is useful as the initial step in the diagnosis and treatment of patients with lumbar canal stenosis. It also may help to differentiate neurogenic from vascular intermittent claudication. 相似文献
46.
47.
O Maeda K Yokokawa T Oka M Namiki H Fujioka M Matsuda M Nishiyama R Shirakura H Hirose T Sonoda 《Urologia internationalis》1986,41(4):318-320
A rare case of a thrombus in the inferior vena cava (IVC) after retroperitoneal lymphadenectomy for a testicular tumor is reported. A computed tomograph performed after the operation incidentally showed a filling defect in the IVC. However, it was impossible to decide whether the defect was due to an ordinary or a neoplastic thrombus. For this reason, a thrombectomy was performed, and postoperatively it was diagnosed as an ordinary thrombus. The cause of thrombi found only in the IVC is reviewed and the indication for thrombectomy is discussed. 相似文献
48.
The contribution of sarcoplasmic reticulum was studied with regard to the increase in arterial contraction induced by a high-potassium depolarization in spontaneously hypertensive rats (SHR). The 20 mmol/l potassium-induced contraction of femoral arteries was faster and greater in 6-week-old SHR than in age-matched normotensive Wistar-Kyoto (WKY) rats. Relaxation after washing the arteries with a Krebs solution was slower in SHR than in WKY rats. When the sarcoplasmic reticulum of SHR arteries had been depleted of calcium by caffeine in a calcium-free solution, the rate of high-potassium-induced contraction of the calcium-depleted SHR arteries was slowed, the same result as that with non-calcium-depleted WKY arteries. In ryanodine-treated arteries, the rate and magnitude of high-potassium-induced contraction were enhanced slightly in SHR and greatly in WKY rats, resulting in no final difference between SHR and WKY rats. Ryanodine slowed the relaxation rate in WKY rats but not in SHR. These results suggest that the diminution in ability of sarcoplasmic reticulum to sequester calcium may be responsible for the faster rate and greater magnitude of high-potassium-induced contraction with the slower relaxation in SHR arteries. We postulated that genetic malfunction of sarcoplasmic reticulum causes the increased contraction of arterial smooth muscle leading to the enhanced vasoconstriction and elevated blood pressure in SHR. 相似文献
49.
Potentiating effect of inhaled acetaldehyde on bronchial responsiveness to methacholine in asthmatic subjects.
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BACKGROUND--It has recently been reported that acetaldehyde induces bronchoconstriction indirectly via histamine release. However, no study has been performed to assess whether acetaldehyde worsens bronchial responsiveness in asthmatic subjects so this hypothesis was tested. METHODS--Methacholine provocation was performed on three occasions: (1) after pretreatment with oral placebo and inhaled saline (P-S day), (2) after placebo and inhaled acetaldehyde (P-A day), and (3) after a potent histamine H1 receptor antagonist terfenadine and acetaldehyde (T-A day) in a double blind, randomised, crossover fashion. Nine asthmatic subjects inhaled 0.8 mg/ml acetaldehyde or saline for four minutes. After each inhalation a methacholine provocation test was performed. RESULTS--Methacholine concentrations producing a 20% fall in FEV1 (PC20-MCh) on the P-A day (0.48 mg/ml, 95% CI 0.21 to 1.08) and T-A day (0.41 mg/ml, 95% CI 0.22 to 0.77) were lower than those on the P-S day (0.85 mg/ml, 95% CI 0.47 to 1.54). There was no change in the PC20-MCh between the P-A and T-A days. A correlation was observed between the logarithmic values of PC20-MCh (log PC20-MCh) on the P-S day and the potentiating effect of acetaldehyde on the methacholine responsiveness [(log PC20-MCh on P-A day)-(log PC20-MCh on P-S day)] (rho = 0.82). CONCLUSIONS--Acetaldehyde induces bronchial hyperresponsiveness in patients with asthma by mechanisms other than histamine release. 相似文献
50.
T Bando K Nishi T Ohka M Yasui M Fujimura T Matsuda 《Nihon Kyōbu Shikkan Gakkai zasshi》1992,30(5):856-861
We evaluated the bronchial hyperresponsiveness to methacholine in the two cases of eosinophilic pneumonia with infiltration of eosinophils into bronchial mucosa. Bronchial responsiveness was not increased in either case in spite of marked infiltration of eosinophils into the bronchial mucosa and submucosa. Hypodense eosinophils are reported in the sputum of patients with bronchial asthma. This suggests that infiltration of activated eosinophils into the bronchial mucosa is an essential factor in bronchial hyperresponsiveness. 相似文献