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排序方式: 共有489条查询结果,搜索用时 31 毫秒
1.
目的:比较正常肝组织与肝癌AH 109A,吉田肉瘤中谷氨酸脱氢酶,胆碱氧化酶和葡萄糖-6-磷酸酶的活力对~(67)Ga摄取与积累的影响;方法:制备~(67)Ga枸橼酸溶液给大鼠静注后处死大鼠,制备亚细胞悬液,液闪计数器测定放射活度.结果:~(67)Ga的放射活性在正常肝组织溶酶体中(55%积聚)显著高于肝癌AH109A(32%积聚)和吉田肉瘤(18%)积聚.谷氨酸脱氢酶的活力在正常肝组织,肝癌和吉田肉瘤分别是1830±s 320 U·L~(-1),23±s 6 U·L~(-1)和7±s 2 U·L~(-1);胆碱氧化酶的活力分别是46±s 10 U·L~(-1),25.0±s 0.4 U·L~(-1),2.0±0.4 U·L~(-1);葡萄糖-6-磷酸酶活力分别是2550±s 180 U·L~(-1),84±s 14 U·L~(-1),78±s13 U·L~(-1).结论:正常肝组织中溶酶体酶活力很强,对~(67)Ga的积累起较大作用.癌变组织酶活力降低而作用减弱.吉田肉瘤细胞无肝细胞特点,其溶酶体对~(67)Ga积累作用不大.  相似文献   
2.
The actions and interactions of purified recombinant human (rh) interleukin 4 (IL-4) and granulocyte colony-stimulating factor (G-CSF) on the clonogenicity of human leukemic cell line U937 were studied in vitro. Parameters analyzed were the suppression of stem cell generation using sequential clonal cultures, alterations of surface antigen expression, and morphological changes. IL-4 alone (10 U/ml) and G-CSF alone (1000 U/ml) only slightly reduced colony numbers (80% +/- 7% and 87% +/- 7% of control colonies, respectively). However, IL-4 interacted synergistically with G-CSF to further reduce the colony number (46% +/- 8% of control colonies) and suppress the self-renewal ability (clonogenicity) of U937 cells. This synergistic effect was not eliminated by cultures containing neutralizing concentrations of anti-granulocyte-macrophage colony-stimulating factor (anti-GM-CSF), anti-interleukin 6 (anti-IL-6), anti-interferon-alpha (anti-IFN-alpha), anti-IFN-gamma, anti-transforming growth factor-beta (anti-TGF-beta) serum, and anti-tumor necrosis factor-alpha (anti-TNF-alpha) serum. The coexistence of IL-4 and G-CSF was required for at least 48 h to reveal the synergistic action as assessed by preincubation and delayed addition experiments. Combinations of IL-4 and G-CSF showed a significant increase in CD11b expression on U937 cells. This action was not observed with HL60, K562, ML-1, or KG-1 leukemic cell lines, and IL-4 did not show any synergistic suppression of clonogenicity of U937 leukemic cells in combination with other cytokines tested in this study. These results suggest that IL-4 in combination with G-CSF may have some capacity to synergistically suppress human leukemic cells of specific types with loss of clonogenicity.  相似文献   
3.
Nuclear transcription factors in the hippocampus   总被引:7,自引:0,他引:7  
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4.
The distribution of functionally active monoamine oxidase type A (MAO-A) was investigated by in vivo quantitative autoradiography using [14C]clorgyline in normal, conscious rat brain. [14C]clorgyline was synthesized by the methylation reaction of N-desmethylclorgyline using [14C]methyliodide. Sixty minutes after [14C]clorgyline administration (1.58 MBq/animal i.v.), the brains were removed and prepared for autoradiography by washing the brain sections with 5% trichloroacetic acid solution to remove the nonbinding free tracer. The amount of MAO-A was calculated from the regional acid-insoluble tissue radioactivity and the specific activity of the tracer. The highest amount of MAO-A (5.84 nmol/g tissue) was found in the locus coeruleus. The interpeduncular nucleus, habenular nucleus, fasciculus retroflexus, and solitary tract nucleus possessed over 1.6 nmol/g tissue of MAO-A. Among 23 regions of interest, the lowest amount of MAO-A (0.37 nmol/g tissue) was found in the globus pallidus. The findings of this study suggest that the pattern of MAO-A parallels both in neuroanatomical distribution and in density that of norepinephrine and serotonin innervation. The MAO-A concentration was, however, relatively low in the dopamine-related areas. This corresponded to the previous results obtained by histochemical analysis. In addition, among the white matter structures, a high amount of MAO-A was found specifically in the fasciculus retroflexus.  相似文献   
5.
Pyothorax-associated lymphoma (PAL) is a B-cell lymphoma which develops in the pleural cavity of patients with an over-20-year history of pyothorax. Aberrant expression of surface antigens is occassional in PAL, although genotype is not fully investigated. We report here a PAL with dual genotype, i.e., simultaneous immunoglobin (Ig) and T-cell receptor (TcR) gene rearrangement. An 82-year-old woman with pain on the left side of the chest was admitted. She had been suffering from pyothorax after artificial pneumothorax for treatment of tuberculosis of the pulmonary when she was 18 years old. The mass that was confined to the left pleural cavity affected by pyothorax was biopsied and histologically diagnosed as diffuse large cell lymphoma. The tumor cells were positive for CD20, CD16, and TIA-1 but negative for CD79a, CD45RO, CD43, CD3, and CD56. Surface antigen expression was further investigated in cultured cells, showing that the cultured cells did not express representative B-cell markers, except for CD20, as well as T-cell markers, but were positive for CD16, CD30, and CD103. Southern blotting revealed the monoclonally rearranged bands of both Ig heavy chain and TcR gene. The patients died of tumors 14 months after admission. Aberrant genotype and immunophenotype of PAL cells is discussed in reviewing the pertinent literature.  相似文献   
6.
A single-strip miniaturized paper chromatographic method (Mini-PC) was developed using 80%–90% acetone solvent for rapid purity-control of 99mTc-radiopharmaceuticals. Routine 99mTc-radiopharmaceuticals (eight kinds of kit made agents) and diluted agents (in which radiochemical impurities might be formed) were analyzed by Mini-PC and other methods. This showed that, compared with the other methods, the Mini-PC technique is useful for the simple and rapid routine analysis of radiochemical impurities of kit made 99mTc-radiopharmaceuticals.  相似文献   
7.
We describe a case that had recurrent median nerve compression after release of the antebrachial fascia in carpal tunnel release. The nerve was compressed by a palmaris longus tendon that was inserted radially into the thenar fascia. After decompression (detachment of the tendon) the patient had symptom relief. Release of the antebrachial fascia in the presence of this tendon variant carries a risk of median nerve compression by the tendon.  相似文献   
8.
We clarified the modulating action of the endocannabinoid system, and its possible mediation by the arachidonic acid cascade, on the reinstatement of methamphetamine (METH)-seeking behavior, using the intravenous self-administration paradigm in rats. Following 12 days of self-administration of METH, the replacement of METH with saline resulted in a gradual decrease in lever press responses (extinction). Under extinction conditions, METH-priming or re-exposure to cues previously paired with METH infusion markedly increased the responses (reinstatement of drug-seeking). The cannabinoid CB1 receptor antagonist, SR141716A, blocked this behavior. Although the cannabinoid agonist, Delta8-tetrahydrocannabinol (THC), had no effects by itself, coadministration of the agonist and METH at small doses reinstated the drug-seeking behavior. THC attenuated the effects of the reinstatement-inducing dose of METH, but enhanced the effect of cues. Either given repeatedly during the extinction or singly, 24 h before the first METH-priming or cues challenge, THC suppressed the reinstatement. In another set of experiments, we found that diclofenac, a cyclooxygenase inhibitor, also attenuated the reinstatement induced by exposure to cues or drug-priming. These results suggest that the endocannabinoid system, through possible mediation by the arachidonic acid cascade, serves as a modulator of the reinstating effects of METH-priming and cues. Extending the current view on the treatment of drug dependence, these results indicate that endocannabinoid-activating substances as well as cyclooxygenase inhibitors may be promising as antirelapse agents.  相似文献   
9.
10.
An accelerated polyol pathway in diabetes contributes to the development of diabetic complications. To elucidate diabetic nephropathy involving also renal tubular damage, we measured urinary sorbitol concentration concomitantly with urinary N-acetyl-D-glucosaminidase (NAG) excretion in WBN-kob diabetic rats.Twenty-four-hour urinary sorbitol concentrations increased in the diabetic rats in parallel with whole blood sorbitol concentrations. An increase in 24-h urinary NAG excretion coincided with the elevated urinary sorbitol levels in the diabetic rats. The administration of epalrestat, an aldose reductase inhibitor, reduced the increased whole blood and urinary sorbitol concentrations and urinary NAG excretion concomitantly with renal aldose reductase inhibition in the diabetic rats.These results indicate that diabetic nephropathy involves distorted cell function of renal tubules, and that treatment with epalrestat may prevent at least the progress of the nephropathy.  相似文献   
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