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971.
The function of ANP in the cardiovascular regulation is very similar with the TCM theory of "the Heart governs blood circulation". Using the method of cardiac impedance to check cardiac output and the method of radioimmunoassay (RIA) to check plasma ANP, the result showed that in the status of Blood Deficiency Syndrome, cardiac function was impaired, there were reduced kinemia and stroke volume, as well as markedly raised plasma ANP and peripheral resistance. The above-mentioned indexes were significantly different from those of normal group (P < 0.01). Using multivariate regression analysis, cardiac output was negatively correlated with the plasma ANP (P < 0.05). 23 cases with Blood Deficiency Syndrome showed normal hemoglobin, but an evidently changed cardiac output and plasma ANP were closely related with the level of the Blood Deficiency. Both parameters might serve as the objective basis to reflect the level of Blood Deficiency to facilitate the clinical diagnosis of the patient. 相似文献
972.
A P DeCaprio D C Spink X Chen J H Fowke M Zhu S Bank 《Chemical research in toxicology》1992,5(4):496-504
Carbon disulfide (CS2) is an industrial solvent used in rayon production and as an organic synthetic precursor. It is also a member of the class of neuropathy-inducing xenobiotics known as the "neurofilament (NF) neurotoxicants". Current hypotheses propose direct reaction of CS2 with NF lysine epsilon-amine moieties as a step in the mechanism of this neuropathy. In this study, covalent CS2 binding in a lysine-containing dipeptide and in bovine serum albumin (BSA) in vitro was characterized. Dipeptide and BSA, incubated with 14CS2, exhibited stable incorporation of radioactivity after removal of unbound CS2 and reincubation in physiological buffer for up to 10 days. In contrast, free thiol levels decreased from a maximum immediately following CS2 exposure to near-base-line levels after 10 days, consistent with time-dependent conversion of initially formed N-substituted dithiocarbamate adducts into secondary products. HPLC/thermospray-MS and HPLC/UV photodiode-array analysis of CS2-dipeptide adducts confirmed dithiocarbamate formation and demonstrated their conversion into N-alkylisothiocyanates and, ultimately, N,N'-disubstituted thioureas and ureas. The results of UV spectrophotometry of CS2-treated BSA were also consistent with loss of dithiocarbamate and appearance of thioureas. Similar time-dependent formation of these products, in addition to N,N'-disubstituted thiuram disulfides, was demonstrated in CS2-treated BSA by means of 13C-NMR spectroscopy. SDS-PAGE analysis of adducted protein revealed a discrete, higher mobility band, likely representing a specific intramolecular cross-link. In contrast, no evidence for intermolecular protein cross-linking was obtained. Identical results were obtained with cysteinyl-blocked BSA, indicating the lack of formation of N,S-dialkyldithiocarbamate (dithiourethane) cross-links in these preparations.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
973.
国产长效皮下埋植剂和Norplant的药物体外释放比较 总被引:7,自引:1,他引:6
本文研究了国产18-甲基炔诺酮硅橡胶长效皮下埋植剂的药物体外释放,并与进口Norplant进行了比较。释放试验采用水平振荡法,实验条件符合“漏槽”状态的要求。用紫外分光光度法在240 nm波长处测定18-甲基炔诺酮每天的体外释放量。二年多体外释放试验的实验结果表明:国产埋植剂的药物体外释放无爆破效应,释药速度稳定,为零级速度。平均每天释放量为85μg。体外释放的重现性好。进口Norplant则有明显的爆破效应,经10天释放,才趋于稳定,平均每天释药量为68μg。 相似文献
974.
975.
The mechanism by which nerve - muscle contacts are reduced during postnatal development of the rat soleus muscle was investigated using electrophysiological methods. Between days 7 and 9 after birth, soleus muscle fibres lose 0.19–0.24 terminals per muscle fibre within 24 h. A much more rapid loss of contacts is seen when muscles are exposed in vitro to acetylcholine (10−3 g/ml). In this case 0.67–0.87 terminals per muscle fibre lose contact within 2 h. The loss of neuromuscular contacts induced by acetylcholine can be reduced by preincubating the muscles in solutions containing acetoxymethyl ester of 1,2-bis(2-amino-phenoxylethane-N,N1 ;N1 -tetraacetic acid (BAPTA-AM), a Ca2+ chelating agent that enters cells and reduces the Ca2+ transients inside the cell. Treatment of muscles with nifedipine, which blocks dihydropyridine-sensitive (L-type) Ca2+ channels, also reduced the acetylcholinesterase-induced loss of neuromuscular contacts. The results indicate that transient increases in Ca2+ inside nerve terminals contribute to loss of neuromuscular contacts, and that these increases occur by Ca2+ entry through L-type channels. 相似文献
976.
977.
作者采用显微外科技术切除脑脓肿40例,在切除前,先用自制三通装置穿刺脓肿,并用10%甲醛溶液及庆大霉素溶液冲洗脓腔,然后在手术显微镜下切除脓壁。随访3~5年,治愈率98.0%(38例),复发1例,死亡2例。 相似文献
978.
Summary This study was designed to compare the degree of reactive astrogliosis occurring around a puncture wound in the brain of normal rats and at different intervals after a similar puncture wound in rats with a portocaval anastomosis. The gliosis was evaluated by the number of astrocytes, the thickness of their processes and the intensity of the glial fibrillary acidic protein immunoreactivity. After the puncture wound in the brain of rats with a portocaval anastomosis, the gliosis varied at different intervals being: (1) decreased at 10 days, (2) markedly increased at 5 weeks and (3) significantly decreased at 8, 12, and 16 weeks. These findings suggest that 5 weeks after portocaval anastomosis, an active proliferation of the metabolically altered astrocytes occurs with heightened synthesis of glial fibrillary acidic protein in the period of adaptive compensation, the so-called compensatory rebound. At 8 weeks or more after portocaval anastomosis, these altered astrocytes were considered to be in the phase of decompensation and incapable of maintaining the reactive response which occurred in normal rats. The compensatory rebound and decompensatory decline illustrate the dynamic plasticity of the reactive astrogliosis.Supported by grant from the National Foundation of Natural Sciences No. 386-0956. This paper was read at the XIth International Congress of Neuropathology, September 7, 1990 in Kyoto, Japan 相似文献
979.
Zhu L Fratiglioni L Guo Z Basun H Corder EH Winblad B Viitanen M 《Stroke; a journal of cerebral circulation》2000,31(1):53-60
BACKGROUND AND PURPOSE: Both stroke and the apolipoprotein E (APOE) epsilon4 allele increase the risk of dementia. However, the interaction between stroke and APOE on dementia is still unclear. We addressed this topic by using a longitudinal design. METHODS: We followed up a community cohort of 1301 subjects aged >/=75 years, who did not have dementia at baseline. Among them, 92 subjects had a history of stroke (from 3 months to 16 years before baseline interview). After the 3-year follow-up, 224 dementia cases had been diagnosed. During the period of follow-up, 91 subjects had a first occurrence of stroke (incident stroke). The APOE genotype was known for 985 subjects. Cox proportional hazards regression models were constructed to estimate the risk for dementia in terms of relative risks (RRs) for stroke and the APOE epsilon4 allele, with adjustment for age, sex, education, systolic blood pressure, antihypertensive medication use, and heart disease. RESULTS: In the entire study population, RRs for dementia related to history of stroke and incident stroke were 1.7 (95% CI, 1.1 to 2.6) and 2.4 (95% CI, 1.6 to 3.5), respectively, after adjustment for all potential confounders. Subjects with stroke that occurred within 3 years before baseline had RR of 2.4 (95% CI, 1.4 to 4.2), whereas those with stroke occurring >3 years before baseline had RR of dementia of 1.1 (95% CI, 0.6 to 2.3). Among those with APOE information, individuals with only history of stroke (that occurred within 3 years before baseline) had RR of 3.1 (95% CI, 1.4 to 6.6), individuals with only the APOE epsilon4 allele had RR of 1.7 (95% CI, 1.1 to 2.5), and individuals with both factors had RR of 5.3 (95% CI, 2.1 to 13.4). The corresponding figures when incident stroke was examined instead of history of stroke were 2.3 (95% CI, 1.3 to 4.1), 1.7 (95% CI, 1.1 to 2.4), and 4.6 (95% CI, 2.0 to 10.6), respectively. The RR of interaction term for history of stroke and APOE epsilon4 was 1.1 (95% CI, 0.3 to 3.8; P=0.8). The corresponding figure was 1.2 (95% CI, 0.4 to 4.4; P=0.7) for incident stroke and APOE epsilon4. Furthermore, the RRs of dementia without any stroke and dementia with stroke in relation to APOE epsilon4 were 1.6 (95% CI, 1.1 to 2.3) and 1.2 (95% CI, 0.6 to 2.4), respectively. In addition, the APOE epsilon4 allele was not significantly related to the occurrence of stroke (RR=0.8; 95% CI, 0.5 to 1.5). CONCLUSIONS: A relatively fresh stroke is a risk factor for dementia. APOE epsilon4 increases the risk of dementia without stroke but not dementia with stroke. Our data do not support a multiplicative effect of stroke and the APOE epsilon4 allele on the risk of dementia. However, both factors seem to have an additive effect on the risk of dementia. The APOE epsilon4 allele does not increase the risk of stroke in this Swedish elderly population. 相似文献
980.
目的 分离和测定非那甾胺中5β-异构体杂质。方法 高效液相色谱法,色谱柱为DiamonsilTMC18柱(4.6 mm×200 mm,5μm),流动相为乙腈-四氢呋喃-水(3:1:8),流速为1.5 mL·min-1,检测波长为210nm,柱温25℃。结果 非那甾胺与5β-异构体能有效分离,两者最低检测浓度均为0.05μg·mL-1。结论 本法操作简便,重现性好,可有效控制非那甾胺的质量。 相似文献