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101.
The local Shwartzman reaction occurred in germfree rabbits which had no natural antibody to endotoxin and none or only a very small amount of immunoglobulin G. From the results it was concluded that the presence of natural antibody to endotoxin is not a prerequisite of the production of the local Shwartzman reaction by bacterial endotoxin.  相似文献   
102.
Tumor necrosis factor (TNF) is known to regulate the proliferation and function of vascular endothelial cells (ECs). We have examined the effects of TNF on the growth and aging of human ECs of different origins and compared them with those in human normal diploid fibroblasts. The results obtained were as follows: (1) TNF reduces the growth rate and in vitro life span of ECs in both dose- and treatment length-dependent fashions; (2) ECs are significantly more sensitive to TNF than fibroblasts; and (3) the life span shortening effect of TNF on ECs increases as a function of in vitro cell age. These results suggest that the aging of ECs is modified by TNF exposure.  相似文献   
103.
Pheochromocytoma usually shows prominent nuclear atypia, but the presence of such atypical cells is known to be an unreliable predictor of malignancy. DNA ploidy of pheochromocytomas has been analyzed by flow cytometry or photospectrometry on paraffinem-bedded tissue, but the results were controversial. We performed DNA analysis on cytology specimens of 11 pheochromocytomas using an image analysis system. All tumors had a mixed pattern of a large population of diploid cells and a small population of polyploid cells. DNA content correlated with nuclear size, and larger cells had more DNA content. Such larger tumor cells had polyploid nuclei, such as 4 C, 8 C, 16 C, and 32 C, in both malignant and benign pheochromocytomas. The larger polyploid nuclei may result from difficulty of duplication at the mitotic phase of the cell cycle.  相似文献   
104.
Imatinib mesylate is a new drug that can inhibit the tyrosine kinase activity of Bcr-Abl, the receptors for platelet-derived growth factor receptor(PDGF) and stem cell factor, or c-kit. Chronic myeloid leukemia (CML) is distinguished by the presence of a reciprocal translocation between chromosomes 9 and 22 that results in a shortened chromosome 22, termed the Philadelphia(Ph) chromosome. As a result of the translocation, a fusion gene called the Bcr-Abl gene is created from two normal cellular genes, encoding a chimeric Bcr-Abl protein with a deregulated tyrosine kinase activity. The expression of Bcr-Abl tyrosine kinase has been shown to be necessary and sufficient for the transformed phenotype of CML cells. Imatinib can block the kinase activity of Bcr-Abl, thus inhibiting the proliferation of Ph-positive progenitors, and has shown activity against all phases of CML, though responses are most substantial and durable in patients in the chronic phase. An international phase III study which compared the efficacy of imatinib with that of interferon alpha combined with low-dose cytarabine in newly diagnosed chronic-phase CML showed the rate of major cytogenetic response at 24 months was 90%, including 82% of complete cytogenetic response. These results indicated that imatinib was superior to interferon-containing treatment as a first-line therapy. More than 10,000 patients worldwide, including those in Japan, have been treated with imatinib in clinical trials, and a lot of information has been accumulated on the use of this drug. The aim of this article is to review the use of this drug and the practical management of patients with chronic myeloid leukemia.  相似文献   
105.
The immunolocalization of cathepsins B(CB), H and L and cystatins(C) and(C) were examined in the hippocampus of cases of sporadic Alzheimer's disease (12 cases), parkinsonism-dementia complex on Guam (eight cases), senile dementia of Alzheimer type (two cases), aged subjects with marked senile change (one case) and controls (12 cases, including six normal subjects). CB was lower in most nerve cells in patients than in controls, but markedly increased at the sites of intracellular neurofibrillary tangles (NFTs) and degenerative neurites and/or dendrites in and outside senile plaques (SPs), indicating its close involvement in the metabolisms of various proteins in NFT and SPs. Abundant C and C were demonstrated in SP amyloid, suggesting that they are amyloid constituents or co-exist with amyloid. The present study indicated that CB, C and C are closely involved in abnormal protein metabolism in NFTs and SP amyloid and suggested that degeneration or denaturation of intracellular proteins, including substrates for proteases and lysosomes, from some acquired cause, results in absolute and/or relative overload for these proteolytic systems, including their inhibitors. This results in incomplete and/or abnormal proteolysis related to NFT and/or amyloid formation.  相似文献   
106.
Summary.  To obtain reagents to functionally map the PA protein, we produced monoclonal antibodies specific to this protein. Twenty-two monoclonal antibodies reacting with PA protein in ELISA were divided into 10 groups on the basis of competitive binding patterns to this protein. Of these, seventeen monoclonal antibodies bound to PA polypeptide spanning amino acids 101–400 and three bound to that of amino acids 518–600, while the other two did not react with any PA polypeptides tested with the exception of full-length PA. Among these monoclonal antibodies, only five reacted with PA in A/PR/8/34 virus-infected cells in indirect immunofluorescence assay. Thus, we obtained monoclonal antibodies that recognize at least 10 distinct regions of the PA molecule. These monoclonal antibodies should be useful in dissecting functions of the PA protein. Received September 6, 1999/Accepted January 5, 2000  相似文献   
107.
Antineutrophil cytoplasmic antibodies (ANCA) for two antigens, i.e. myeloperoxidase (MPO) and lactoferrin (LF) in sera from 19 IgA nephropathy (IgAN), 3 adult Henoch-Sch?nlein purpura (HSP) and 8 child HSP patients were examined by enzyme-linked immunoabsorbent assay (ELISA) for immunoglobulin isotypes. All of child HSP patients showed negative ANCA. On the other hand, one IgAN patient and two adult HSP patients showed weak positivity for IgA class anti-MPO antibody. There was no patients who showed positivity for IgG and IgM class anti-MPO antibody. In anti-LF antibody, one IgAN and one adult HSP showed positivity in IgG class; 2 IgAN and 2 HSP in IgA class and 2 IgAN and one HSP in IgM class. These results indicate that adult HSP patients have higher prevalence of IgA class anti-MPO antibody and anti-LF antibody than IgAN or child HSP.  相似文献   
108.
Sex, age and 21 routine liver function assays were analyzed by stepwise selection and the best-of-all-possible-combinations method to identify a small group of assays valuable in establishing which liver cirrhosis (LC) patients have a high risk of hepatocellular carcinoma (HCC), when alpha-fetoprotein (AFP) is not elevated. Data was obtained from 115 HCC and 122 LC patients on admission. Tumor size correlated with AFP (0.73), alkaline phosphatase (ALP, 0.47), leucine aminopeptidase (LAP, 0.42), lactic dehydrogenase (LDH, 0.42), and the glutamic oxaloacetic transaminase (GOT)/glutamic pyruvic transaminase (GPT) ratio (GOT/GPT, 0.41). The mean of the correct diagnosis rates (CDR) of HCC and LC utilizing AFP as the sole parameter (89%) was markedly higher than those of the other parameters. The best-of-all-possible-combinations method presented a more powerful combination than stepwise selection. The best combination of 7 parameters (LAP, GOT/GPT, choline esterase, one-hour erythrocyte sedimentation rate, age, albumin/globulin ratio, and total bilirubin) presented a mean CDR of 80%, HCC CDR of 77%, and false positive rate of 18%. LC patients statistically diagnosed as having HCC by these 7 parameters are proposed as high risk patients. Fourteen (78%) of 18 HCC patients who were AFP-negative were statistically diagnosed. This analysis can be applied to LC patients to distinguish those that should be followed closely by imaging diagnostic techniques.  相似文献   
109.
Autonomic nervous function was evaluated by means of power spectral analysis of heart rate variability in patients with essential hypertension who showed early morning rise of blood pressure (BP). We monitored ambulatory (BP) and physical activity in 80 untreated patients using TM 2425 (A&D Co.Ltd.). Early morning rise of BP was defined a patient's blood pressure obtained between 6:00 to 9:00am is 170mmHg or higher. Patients who showed early morning rise of BP were categorized into groups. Twenty patients, whose mean BP obtained between 6:00 to 9:00am were higher than those obtained between 3:00 to 600am by 30mmHg or more, were defined as a surge type. Sixty patients, in whom the difference in BP was less than 30mmHg, were defined as a sustained type. Power spectral analysis of hourly R-R intervals for 24 hours was performed to obtain the low frequency power (LF, 0.04 to 0.15 Hz) and high frequency power (HF, 0.15 to0.04 Hz). LFn and LF/HF ratio were considered to be indexes of sympathetic nervous activity, and HF parasympathetic nervous activity, respectively. Between 3:00 to 6:00am, LFn and LF/HF were significantly higher and HF was significantly lower in the sustained type patients than in the surge type patients. LF/HF and LFn in the surge type elevated significantly beween 6:00 to 9:00am. These results indicate that both the loss of nocturnal decline in BP in the sustained type and the morning rise in BP in the surge type to occurred in association with changes in autonomic nervous system.  相似文献   
110.
We examined synaptic plasticity in the optic tectum of rainbow trout by extracellular recordings. We found that the field-excitatory postsynaptic potential in the retinotectal synapses was potentiated by repetitive stimuli of 1.0 Hz for 20 s to the retinotectal afferents. The long-term potentiation (LTP) developed slowly, and was maintained for at least 2 h. Applications of an antagonist for N-methyl-D-aspartic acid (NMDA) receptors or Mg2+-free saline showed that activation of NMDA receptors was required to form the LTP beyond the induction period. The present findings indicate that presynaptic stimulation in the retinotectal synapses causes LTP mediated by NMDA receptors in the optic tectum of rainbow trout.  相似文献   
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