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991.
992.
The pathogenesis of autoimmune pancreatitis is unknown. In the present study we used high-throughput sequencing with next generation sequencing to identify the candidate genes associated with AIP. A total of 27 type 1 AIP patients and 30 healthy blood donors were recruited, and DNA samples were isolated from their mononuclear cells. A high-throughput sequencer with an original custom panel of 1031 genes was used to detect the genetic variants in each sample. Polymorphisms of CACNA1S (c.4642C>T), rs41554316, rs2231119, rs1042131, rs2838171, P2RX3 (c.195delG), rs75639061, SMAD7 (c.624delC) and TOP1 (c.2007delG), were identified as candidate genetic variants in patients with type 1 AIP. P2RX3 and TOP1 were significantly associated with AIP, even after adjusting bay means of Bonferroni's correction. In addition, we also identified eight candidate genetic variants that were associated with the relapse of type 1 AIP, namely: rs1143146, rs1050716, HLA-C (c.759_763delCCCCCinsTCCCG), rs1050451, rs4154112, rs1049069, CACNA1C (c.5996delC) and CXCR3 (c.630_631delGC). Finally polymorphisms of rs1050716 and rs111493987 were identified as candidate genetic variants associated with extra-pancreatic lesions in patients with type 1 AIP. These candidates might be used as markers of AIP susceptibility and could contribute to the pathogenesis of type 1 AIP.  相似文献   
993.
Monoclonal antibodies against horse kidney outer medulla (Na+ + K+)-ATPase were prepared. One of these antibodies (M45-80), was identified as an IgM, recognized the alpha subunit of the enzyme. M45-80 had the following effects on horse kidney (Na+ + K+)-ATPase: (1) it inhibited the enzyme activity by 50% in 140 mM Na+ and by 80% in 8.3 mM Na+; (2) it increased the Na+ concentration necessary for half-maximal activation (K0.5 for Na+) from 12.0 to 57.6 mM, but did not affect K0.5 for K+; (3) it slightly increased the K+-dependent p-nitrophenylphosphatase (K-pNPPase) activity; (4) it inhibited phosphorylation of the enzyme with ATP by 30%, but did not affect the step of dephosphorylation; and (5) it enhanced the ouabain binding rate. These data are compatible with a stabilizing effect on the E2 form of (Na+ + K+)-ATPase. M45-80 was concluded to bind to the extracellular surface of the plasmamembrane, based on the following evidence: (1) M45-80 inhibited by 50% the ouabain-sensitive 86Rb+ uptake in human intact erythrocytes from outside of the cells; (2) the inhibition of (Na+ + K+)-ATPase activity in right-side-out vesicles of human erythrocytes was greater than that in inside-out vesicles; and (3) the fluorescence intensity due to FITC-labeled rabbit anti-mouse IgM that reacted with M45-80 bound to the right-side-out vesicles was much greater than that in the case of the inside-out vesicles.  相似文献   
994.
995.
The development of axillary buds, terminal buds, and the shoots extended from them was studied inHydrangea macrophylla. The upper and lower parts in a nonflower-bearing shoot are discernible; the preformed part of a shoot develops into the lower part and the neoformed part into the upper part (Zhou and Hare, 1988). These two part are formed by the different degrees of internode elongation at early and late phases during a growth season, respectively. Leaf pairs in the neoformed part of the shoot are initiated successively with a plastochron of 5–20 days after the bud burst in spring. The upper axillary buds are initiated at approximately the same intervals as those of leaf pairs, but 10–30 days later than their subtending leaves. Changes in numbers of leaf pairs and in lengths of successive axillary buds show a pattern similar to the changes in internode lengths of the shoot at the mature stage. The uppermost axillary buds of the flower-bearing shoot often begin extending into new lateral shoots when the flowering phase has ended. The secondary buds in terminal and lower axillary buds are initiated and developed in succession during the late phase of the growth season. Internode elongation seems to be important in determining the degrees of development of the axillary buds. Pattern of shoot elongation is suggested to be relatively primitive. Significances of apical dominance and environmental conditions to shoot development are discussed.  相似文献   
996.
Glucose transport systems in cultured neuronal cells and astrocytes of rats were characterized by measuring the uptake of 2-deoxy-D-[3H]glucose ([3H]2-DG) into the cells. Various sugars inhibited 2-DG uptake by neuronal cells and astrocytes similarly, a finding indicating that the substrate specificities of the transporters in the two types of cells were almost the same. However, the Km values for 2-DG of neuronal cells and astrocytes were 1.7 and 0.36 mM, respectively. The uptake of 2-DG was strongly inhibited by cytochalasin B. Nucleosides, such as adenosine, inosine, and uridine, inhibited 2-DG uptake competitively in both neuronal cells and astrocytes. The uptake by both types of cells were also inhibited by forskolin, but not by cyclic AMP, an observation suggesting that forskolin bound directly to the transporters to cause inhibition. Its inhibition was competitive in astrocytes and noncompetitive in neuronal cells. Astrocytes contained a glucose transporter with a subunit molecular weight of 45K, as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis after photoaffinity labeling using [3H]cytochalasin B as a probe.  相似文献   
997.
The effect of route of administration on the induction of micronucleated polychromatic erythrocytes (MNPCEs) was examined. 6-Mercaptopurine monohydrate (6-MP) was administered intraperitoneally (i.p.) or orally (p.o.) to 2 strains of mice, MS/Ae and CD-1. From the results of an acute toxicity test and a pilot micronucleus test, the doses selected for the final micronucleus test were 12.5-100 mg/kg for the i.p. route and 25-200 mg/kg for the p.o. route. The sampling time was 48 h. Frequencies of MNPCEs increased dose-dependently by the i.p. route but peaked at 50 or 100 mg/kg for the p.o. route. 6-MP induced MNPCEs more efficiently after p.o. administration than after i.p. treatment in both strains.  相似文献   
998.
The structure of theDRB1 * 03 gene has been interpreted as the product of a gene conversion event involving aDRB3 gene as donor and resulting in the introduction of two short segments of the DRB3 sequence into theDRB1 locus. The serological counterpart of this double insertion is the TR81 specificity. Consequently, the TR81-specifying sequences can reside on eitherDRB1 orDRB3, or on both loci. Within each of the two sequence stretches a single nucleotide may be responsible for the generation of the TR81 alloantigen. Oligonucleotide probes corresponding to these stretches and to their allelic variants were constructed. They were used, under stringent hybridization conditions, to detect TR81-specifying sequences in the DNA ofHLA-homozygous cell lines carrying different haplotypes of the DRw52 family. Prior to hybridization the DNA was amplified with either DRB1-specific or DRB3-specific primers. Using this approach it was possible to perform a DNA typing of the TR81-specifying sites separately on both theDRB1 locus and theDRB3 locus.  相似文献   
999.
Summary Short photoreceptor cells of the lamprey retina exhibited a 30% increase in the width of the myoid process and a 20% increase in that of the axonal process during a 12-h light period, compared to the measurements obtained during a 12-h dark period. An increase in the amount of cytoplasm, dilation of ER cisterns, and swelling of the nucleus appeared to cause the enlargement of the myoid parts. Accumulation of synaptic vesicles occurred concurrently with a thickening of the axonal process. These morphological changes presumably represent a phase of the diurnal cycle and current synaptic activity of the short cell. By contrast, the long photorecpetor cell showed neither measurable changes nor any indication of retinomotor movement.  相似文献   
1000.
Human fibroblasts (WI-38 cells) were found to enhance mucus accumulation by human scirrhous carcinoma cells (KATO-III cells). Coculture of KATO-III with WI-38 cells resulted in enlargement of the KATO-III cells and increases in the proportions of PAS- and colloidal iron-positive KATO-III cells. These morphological alterations were reversed when the KATO-III cells were again cultured without WI-38 cells. Conditioned media from cultures of WI-38 cells or cocultures of KATO-III and WI-38 cells induced the same morphological alterations in KATO-III cells, suggesting that WI-38 cells produce a factor or factors that enhance mucus accumulation in KATO-III cells. This factor seemed to be a protein with a molecular weight of more than 10,000 daltons.  相似文献   
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