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51.
磁感应热疗用镍-铜热籽对L-929细胞及兔肌肉组织的影响 总被引:1,自引:0,他引:1
目的探讨磁感应热疗用镍-铜热籽体外升温特性以及对细胞与组织的影响。方法测量感应热籽在离体兔肝组织内升温特性;通过细胞毒性试验(MTT试验)评价该治疗热籽浸提液体外细胞毒性;溶血试验评价其有无溶血作用;兔体内肌肉埋植试验来评价其材料的组织毒性。结果实验中所用的铁磁热籽在离体兔肝内具有良好的升温效果;细胞毒性试验结果显示镀金热籽对L-929细胞毒性为1级,属对细胞无毒性范畴;溶血试验中镀金热籽的溶血率3.25%(〈5%),表明实验用热籽无溶血作用;各期体内埋植试验反映了材料在肌肉组织中不同的炎性反应。结论自制的镀金镍-铜热籽在感应加温交变磁场中可升温到适合的温度,对L-929细胞毒性为1级,无溶血作用。 相似文献
52.
Darmopil S Muñetón-Gómez VC de Ceballos ML Bernson M Moratalla R 《The European journal of neuroscience》2008,27(3):580-592
Tyrosine hydroxylase (TH)-immunoreactive (ir) neurones are detected in the striatum of animals after dopamine depletion and also in human parkinsonian patients. Although there is extensive evidence for TH-ir neurones in the lesioned rodent striatum, there are few details regarding the molecular phenotype of these neurones, regulation of their TH expression after l -3,4-dihydroxyphenylalanine (L-DOPA) treatment and their function. In the present study, we examined the time-course of appearance of TH-ir neurones in the mouse striatum after 6-hydroxydopamine (6-OHDA) lesion and determined their molecular phenotype. We found that TH-ir neurones appeared in the striatum as early as 3 days after a 6-OHDA lesion. By 1 week after the lesion, the number of TH-ir neurones started to decrease and this decrease progressed significantly over time. Treatment with L-DOPA increased both the number of TH-ir neurones and the intensity of their immunolabelling. The TH-ir neurones that appear after the 6-OHDA lesion in the striatum are not newly generated cells as they did not incorporate 5-bromo-2-deoxyuridine. We found that the vast majority of TH-ir neurones colocalized with dynorphin and enkephalin, suggesting that they are projection neurones of the direct and indirect striatal output pathways. TH-ir neurones did not express the dopamine transporter but half of them expressed amino acid decarboxylase, an enzyme required for dopamine synthesis. Finally, striatal TH-ir neurones are functionally active, expressing the neuronal activation marker FosB in response to L-DOPA treatment. Promotion of these striatal TH-ir neurones may be beneficial in Parkinson's disease, particularly in the early stages when dopamine denervation is incomplete. 相似文献
53.
应用双抗体夹心ELISA法测定42例寻常性银屑病患者血清sIL-2R水平。结果显示银屑病患者的sIL-2R明显高于正常人(P<0.01),且与疾病的活动性和皮损范围无关。该结果提示银屑病患者存在细胞因子的异常。 相似文献
54.
Background
Ischemia and reperfusion (I/R) lead to cellular damage. A disturbance of testicular perfusion occurs during the therapy of cryptorchidism and in cases of testicular torsion. This results in the activation of mediator cells with an increasing synthesis of mediators of infection like TNF-α and the expression of cell adhesion molecules like ICAM (intercellular adhesion molecule) and VCAM (vascular cell adhesion molecule) at the cellular surface.Methods
The expression of the cytokines IL-10 and TNF-α and the adhesion molecules ICAM and VCAM after defined testicular I/R injury in nine male transsexuals was evaluated with rt-PCR. Furthermore we examined lactate and the diameter of the testicular tubulus under ischemic conditions.Results
During ischemia ICAM, IL-10, and VCAM do not show significant changes on the side of testicular ischemia and the contralateral side; the same was seen for the tubulus diameter. TNF-α and the testicular lactate values showed a significant change of the expression pattern.Discussion
The statistical changes of TNF-α and testicular lactate are the expression of leukocyte migration, infectious reaction, and immune response. To what extent the TNF-α expression represents a severe immunological reaction remains undefined. This human study shows primary results for the immunological understanding of and cellular response to testicular ischemia. 相似文献55.
Ozden Y?ld?zDemirhan Citak Mustafa Tuzen Mustafa Soylak 《Food and chemical toxicology》2011,49(2):458-463
A novel solid phase extraction procedure for determination of copper, lead and iron in natural water and food samples has been established in the presented work. 1-Phenylthiosemicarbazide (1-PTSC) as ligand and Dowex Optipore L-493 resin as adsorbent were used in a mini chromatographic column. Various analytical conditions for the quantitative recoveries of analyte ions including pH, amounts of adsorbent, eluent, sample volume, etc. were investigated. The recovery values for analyte ions were higher than 95%. The determination of copper, lead and iron was performed by flame atomic absorption spectrometry. The influences of some alkali, alkali earth and transition metals on the recoveries of analyte ions were investigated. The preconcentration factor was 62.5. The limit of detections of the understudied analytes (k = 3, N = 21) were 0.64 μg L−1 for copper, 0.55 μg L−1 for lead and 0.82 μg L−1 for iron. The relative standard deviation was found to be lower than 6%. The accuracy of the method was confirmed with certified reference material (GBW 07605 Tea). The method was successively applied for the determination of copper, lead and iron in water and some food samples including cheese, bread, baby food, pekmez, honey, milk and red wine after microwave digestion. 相似文献
56.
在筛选免疫抑制剂的过程中,找到了一株吸水类链霉菌I2190,属于FK-506类化合物的产生菌,从其发酵产物中已分离出A、B二个组份,基于光谱数据和理化特性的分析,证实12190B和免疫抑制剂FK-520及LD-683590(Immunomycin)均为同一物质。 相似文献
57.
A synthesis is described of optically pure L-2-amino-4-hexynoic acid and its derivatives, which can serve as potentially useful precursors for the preparation of highly tritium labeled norleucine-containing peptides, as well as other side-chain modified peptides. Catalytic tritiation of one derivative of this acetylenic amino acid afforded the (3H)-L-norleucine derivative with a specific activity of 115 ± 5 Ci/mmol. 相似文献
58.
Several high affinity sigma (σ) ligands, such as DTG, JO-1784, (+)-pentazocine, BD-737 and L-687,384, administered at low
doses act as agonists by potentiating N-methyl-D-aspartate (NMDA)-induced activation of pyramidal neurons in the CA3 region of the rat dorsal hippocampus. This potentiation is dose-dependent at doses between 1 and 1000 μg/kg, IV but bell-shaped
dose-response curves are obtained. Other σ ligands like haloperidol, BMY-14802, (+)3-PPP and NE-100 administered at low doses
act as σ antagonists, since they do not modify the NMDA response but suppress the potentiation of the NMDA response induced
by σ agonists. Because high doses of the σ agonists do not potentiate the NMDA response, the present experiments were undertaken
to assess if, at high doses, these σ ligands could also act as σ antagonists and suppress the potentiation induced by low
doses of σ agonists. High doses of DTG, JO-1784, BD-737, and L-687,384, administered acutely, had an effect similar to that
of low doses of haloperidol, by suppressing and preventing the potentiation induced by low doses of DTG, JO-1784, BD-737,
L-687,384 and (+)-pentazocine. High doses of (+)-pentazocine suppressed the effect of a low dose of (+)-pentazocine but did
not affect the potentiation induced by a low dose of the other σ agonists. The potentiation induced by a low dose of a σ1 agonist was not further increased by the subsequent administration of another low dose of a σ1 agonist. All together, these results strongly suggest that more than two subtypes of σ receptors exist in the CNS.
Received: 1 April 1996 / Final version: 14 August 1996 相似文献
59.
Inhibition of transient lower esophageal sphincter relaxation and gastroesophageal reflux by metabotropic glutamate receptor ligands 总被引:7,自引:0,他引:7
Frisby CL Mattsson JP Jensen JM Lehmann A Dent J Blackshaw LA 《Gastroenterology》2005,129(3):995-1004
BACKGROUND & AIMS: Transient lower esophageal sphincter relaxation (TLESR) is the major mechanism of gastroesophageal acid reflux. TLESR is mediated via vagal pathways, which may be modulated by metabotropic glutamate receptors (mGluRs). Group I mGluRs (mGluR1 and 5) have excitatory effects on neurons, whereas group II (mGluR2 and 3) and group III (mGluR4, 6, 7, and 8) are inhibitory. This study determined the effect of mGluRs on triggering of TLESR and reflux in an established conscious ferret model. METHODS: Esophageal manometric/pH studies were performed in ferrets with chronic esophagostomies. TLESR were induced by a gastric load of 25 mL glucose (pH 3.5) and 30 mL air. RESULTS: In control treated animals, gastric load induced 3.52 +/- 0.46 TLESRs per 47-minute study, 89.7% of which were associated with reflux episodes (n = 16). The mGluR5 antagonist MPEP inhibited TLESR dose dependently, with maximal 71% +/- 7% inhibition at 35 micromol/kg (n = 9; P < .0001). MPEP also significantly reduced reflux episodes (P < .001) and increased basal lower esophageal sphincter pressure (P < .05). MPEP inhibited swallowing dose dependently, suggesting a common action on trigger mechanisms for swallowing and TLESR. The more selective analogue, MTEP, had more potent effects (90% +/- 6% inhibition TLESR at 40 micromol/kg; n = 8; P < .0001). In contrast, the group I agonist DHPG tended to increase TLESR. The group II agonist (2R, 4R)-APDC was ineffective, whereas the group III agonist L-(AP4 slightly reduced TLESR (33% at 11 micromol/kg; P < .05). The selective mGluR8 agonist (S)-3, 4-DCPG inhibited TLESR by 54% at 15 micromol/kg (P < .01). CONCLUSIONS: mGluR5 antagonists potently inhibit TLESR and reflux in ferrets, implicating mGluR5 in the mechanism of TLESR. mGluR5 antagonists are therefore promising as therapy for patients with GERD. 相似文献
60.
Medical treatment in pregnancy presents a number of problems for the physician. Does the prescribed medication pose a potential threat by having a teratogenic effect on the fetus if taken early in pregnancy? Could it cause functional disturbances during delivery if taken late in pregnancy? Could the drug interfere with the mother during the normal course of pregnancy, and cause functional disturbances during labor? There are several cardiovascular diseases to which women are prone both before and during pregnancy, the most common being systemic hypertension, rheumatic heart disease with the complications of congestive heart failure and arrhythmias, and to a lesser extent congenital heart disease, primary pulmonary hypertension, cardiomyopathies, and other conditions. The frequency and treatment of these diseases during pregnancy have been reviewed.1–3 This report deals with the direct actions and side effects of various cardiovascular pharmacologic preparations administered during pregnancy. 相似文献