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A potassium channel toxin (AeK) was isolated from the sea anemone Actinia equina by gel filtration on Sephadex G-50 and reverse-phase HPLC on TSKgel ODS-120T. AeK and alpha-dendrotoxin inhibited the binding of 125I-alpha-dendrotoxin to rat synaptosomal membranes with IC50 of 22 and 0.34 nM, respectively, indicating that AeK is about sixty-five times less toxic than alpha-dendrotoxin. The complete amino acid sequence of AeK was elucidated; it is composed of 36 amino acid residues including six half-Cys residues. The determined sequence showed that AeK is analogous to the three potassium channel toxins from sea anemones (BgK from Bunodosoma granulifera, ShK from Stichodactyla helianthus and AsKS from Anemonia sulcata), with an especially high sequence homology (86%) with AsKS.  相似文献   
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OBJECTIVE: To study the prevalence of cardiovascular risk factors in native urban Asian Indians and to look for the occurrence of clustering of these factors. RESEARCH DESIGN AND METHODS: The study included 953 subjects (532 men and 421 women), aged > or = 40 years, selected from a population survey for diabetes, which was conducted in 1994 in Madras, Tamil Nadu, India. Measurements of anthropometry, blood pressure, plasma lipid profile, glucose tolerance, plasma insulin response, and electrocardiogram were made. Based on the normal ranges derived from the population study, abnormalities in anthropometric values, plasma lipids, and insulin values were determined. Age-adjusted prevalences of the abnormalities were calculated using data from a 1991 urban census in Madras. The expected prevalences of the abnormalities in isolation and in combinations were calculated and compared with the corresponding observed figures. RESULTS: The prevalences of risk factors were in the order of central adiposity > dyslipidemia > hyperinsulinemia (2-h) > glucose intolerance > obesity > hypertension. The age-adjusted prevalence of coronary heart disease (CHD) was 3.9% (3.5% in men and 4.5% in women, NS), and T wave inversion was seen in an additional 10.3%. Isolated prevalences of all factors, except hypertension, were in lower frequency than expected. Combinations of each risk factor with one or two more risk factors occurred more frequently (1.3-4 times) than expected by chance. Impaired glucose tolerance and dyslipidemia showed association with hyperinsulinemia, whereas hypertension did not show such an association. CONCLUSIONS: Clustering of the cardiovascular risk factors or the components of insulin resistance syndrome occurs in the native Asian Indian population. This finding under-scores the need for preventive aspects of metabolic disorders and CHD.  相似文献   
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Within the placenta tumour necrosis factor-alpha (TNF-alpha) and its surface receptors TNF-RI and -RII have been detected on villous cyto- and syncytiotrophoblast and a role in trophoblast function/differentiation and turnover has been suggested. Here, we show for the first time that purified villous trophoblasts and cytotrophoblastic BeWo cells extensively shed TNF receptors, suggesting that release of these soluble proteins is an inherent property of trophoblasts. In supernatants of purified villous trophoblasts, TNF-RI and -RII increased from undetectable levels to 307 pg/ml and 484 pg/ml, respectively, within 12 h of cultivation. In BeWo cells, 26 pg/10(5) cells and 54 pg/10(5) cells of soluble TNF-RI and -RII, respectively, accumulated within 24 h of culturing. While forskolin did not alter TNF-RI expression, TNF-RII mRNA, protein and secretion were selectively up-regulated in these choriocarcinoma cells suggesting that elevation of cAMP levels could modulate cellular events by TNF-RII-mediated signal transduction. Interleukin-1, which greatly enhances TNF-alpha release from trophoblast cells, did not alter shedding of both receptors from villous trophoblasts or BeWo cells. Secretion of TNF receptors from the trophoblast may explain the high levels of soluble TNF-binding proteins in urine of pregnant women and could play a role in regulating TNF-alpha activity in the placental villus or protection against the cytotoxic effects of the cytokine.  相似文献   
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Objective

The heavy metals lead (Pb) and mercury (Hg) are ubiquitous environmental pollutants with high neurotoxic potential. We aimed to compare perinatal Pb and Hg concentrations and to explore the potential association between Pb and Hg exposure and newborn anthropometry.

Study design

Pregnant women were recruited in 2005 at the General Hospital Vienna for participation in this longitudinal study. Pb and Hg concentrations were measured in maternal blood and hair, placenta, cord blood, meconium, and breast milk of 53 mother-child pairs by CV-AAS, GF-AAS, and HPLC-CV-ICPMS. We conducted bivariate analyses and categorical regression analysis (CATREG) to evaluate the determinants of Pb and Hg exposure, and of infant anthropometry.

Results

Median Pb and total Hg contents were low, i.e., 25 μg/L (maternal blood-Pb), 13 μg/L (cord blood-Pb), 0.7 μg/L (maternal blood-Hg), and 1.1 μg/L (cord blood-Hg). Hg levels in maternal and fetal tissues were frequently correlated (r > 0.3, P < 0.05, respectively). Regarding Pb, only maternal blood and cord blood concentrations correlated (P = 0.043). Cord blood levels indicated higher Hg exposure but lower Pb exposure relative to maternal blood contents. Adjusted CATREG models indicated the significant predictors of birth length (placenta-Pb, gestational length, meconium-Pb), birth weight (placenta-Pb, gestational length, maternal blood-Pb), and head circumference (maternal education, maternal height). Besides one significant correlation between maternal hair Hg and birth length, the mercury levels were not associated with newborn anthropometry.

Conclusions

Our data implicate that different modes of action may exist for placentar transfer of Pb and Hg as well as that low Pb exposure levels can result in lower birth weight. The findings related to newborn anthropometry need to be confirmed by the examination of larger study groups. Further research is needed to clarify the mechanisms of Pb and Hg transfer via the placenta, and to explore how prenatal Pb exposure is related to intrauterine growth.  相似文献   
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OBJECTIVE: Our aim was to determine from what time onward fetal fibronectin is consistently detectable in the cervicovaginal secretions before delivery and to what extent the actual time of delivery can be better determined by this procedure than by the sole use of the Bishop score. STUDY DESIGN: A fast-reacting fetal fibronectin test was performed on 206 women on their expected date of confinement. In addition, the cervical status was evaluated with use of a modified Bishop score. Follow-up evaluations were subsequently carried out in the course of the routine examinations. RESULTS: Women with a positive fetal fibronectin test result and a high Bishop score were delivered after a median of 1.7 days. Conversely, women with a negative fetal fibronectin test result and a low Bishop score were delivered after a median of 7.1 days. CONCLUSION: Determination of fetal fibronectin in combination with the Bishop score makes it possible to predict the actual time of delivery with a greater degree of accuracy.  相似文献   
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A case of acute postoperative cholecystitis following subtotal gastrectomy for carcinoma has been observed. The combination of temporary intraoperative shock and probably vagal denervation of the gallbladder initiated secondary acute cholecystitis. After an emergency type cholecystectomy the patient recovered.  相似文献   
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