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11.
The market of non-registered pharmaceutical products is growing fast in number and overall costs, not only in the Netherlands, but also in other European countries. These products often give the impression that the consumer may expect 'an effect as from a drug'. Legally, there is a clear distinction between 'drugs' and 'commodities' in the Netherlands; the question is whether legislation and practice concur. In an investigation we analysed texts of advertisements for non-registered pharmaceutical products published in a popular magazine. A method was developed, based on the legal definition of a drug and jurisprudence, to determine in a qualitative and quantitative way the application of medicinal claims. It transpired that in 65% of the analysed advertisements explicit or implicit claims were made. These products should therefore be subject to drugs legislation. Thus, in the Netherlands there is a gap between legislation and practice in advertising non-registered pharmaceutical products.  相似文献   
12.
The age-dependence of the incidence of magnocellular neurosecretory neurons containing abnormal accumulations of peptide in the rough endoplasmic reticulum was examined in homozygous Brattleboro rats and in their wild-type Long Evans counterparts. Neurons in which the immunophenotype of the peptide aggregates indicate that somatic cross-over mutations involving the 5' end of the vasopressin gene and the 3' end of the oxytocin gene have occurred, increased with age in homozygous Brattleboro rats, reaching a maximum of 24 cells per hypothalamus (approximately 0.6% of the vasopressin neurons). The increase occurred in both male and female animals but was significantly greater in females. The average incidence of such cells was 6 times greater in the supraoptic than in the paraventricular nucleus. No such cells could be detected in either nucleus of Long Evans rats despite the evidence for hybrid mRNA in these animals. Moreover, no accumulation of peptide translated from the hybrid mRNAs derived from the 5' end of the oxytocin gene and the 3' end of the vasopressin gene could be detected in either Brattleboro or Long Evans animals. These results strongly suggest that the accumulation of peptide in the rough endoplasmic reticulum of vasopressin neurons in homozygous Brattleboro rats is due to an abnormality other than the somatic crossing-over mutation. A second type of abnormal magnocellular neuron with accumulations of peptide in the rough endoplasmic reticulum, in which the immunophenotype of the peptide reveals products derived only from the oxytocin precursor, was present in both Long Evans and Brattleboro rats, but did not increase with age in Brattleboro rats. The incidence of these cells was similar in the supraoptic and paraventricular nuclei.  相似文献   
13.
目的 探讨高级糖化终产物与糖尿病并发症的关系。方法 采用本实验室自行研制的竞争性酶联免疫吸附分析方法,测定了糖尿病有并发症组病人血浆95例,糖尿病无并发症组人血浆65例,正常对照65例。结果:在糖尿病有并发症组中,高级糖化终产物(AGEs)浓度[(6.625(1.691)U/mL,n=95]明显高于糖尿病无并发症组[(5.904(2.071)U/mL,n=65,P=0.017],也明显高于正常人组[(5.337(1.138,n=65,p〈0.005]。以有无并发症为应变量进行多元logistic回归分析显示,血浆AGEs浓度〉6.085U/ml者,糖尿病并发症发生的危险性增加(OR值为2.989,95%可信限为1.407—6.350)。多元逐步线性回归显示:糖尿病病程、冠心病史与血浆AGEs浓度之间有线性关系。结论血浆AGEs浓度是糖尿病发生并发症的独立危险因素。  相似文献   
14.
目的:研究不同孕期阶段(早、中、晚)孕妇凝血四项、血浆纤维蛋白(原)降解产物[plasma fibrin/fibrinogen degradation products, FDP]、D-二聚体的变化及临床意义,为临床诊疗提供理论支持。方法:回顾性分析2021年1月至2021年12月200例孕妇就诊资料中的凝血四项,纤维蛋白原(fibrinogen, FIB)、凝血酶原时间(prothrombin time, PT)、凝血酶时间(thrombin time, TT)、活化部分凝血活酶时间(activated partial thromboplastin time, APTT)。并对FDP与D-二聚体的检测结果进行统计分析,比较孕早期、中期、晚期三个阶段凝血四项、FDP和D-二聚体水平的变化。结果:孕早期、孕中期与孕晚期PT水平比较,差异有统计学意义(P<0.05);孕早期、孕中期与孕晚期三个阶段的TT相比,差异无统计学意义(P>0.05);孕早期的APTT明显长于中期、晚期孕妇,差异有统计学意义(P<0.05);孕早期、中期、晚期孕妇,随着孕周的增加,FIB水平逐渐升高...  相似文献   
15.
T. TERADA    T. OHTA  Y. NAKANUMA 《Histopathology》1996,29(4):355-361
A few previous studies have demonstrated the expression or mutations of oncogenes and anti-oncogenes as well as that of oncofetal antigens in intraductal papillary-mucinous neoplasm of the pancreas. In this study, we have investigated the immunohistochemical expression of oncogene (ras and c-erbB-2) and anti-oncogene (p53 and retinoblastoma [Rb]) products and oncofetal antigens (CEA, CA19-9 and DUPAN-2) in nine such tumours of the pancreas. In normal pancreas (5 cases), the Rb gene product and CA19-9 were expressed in all cases, while ras and c-erbB-2 gene products, p53 protein, CEA and DUPAN-2 were not expressed. In intraductal papillary-mucinous tumours (n = 9), ras, c-erbB-2, p53 and Rb gene products were present in 4/9 (44%), 7/9 (78%), 0.9 (0%) and 6/9 (67%) cases, respectively. CEA, CA19-9 and DUPAN-2 were expressed in 8/9 (89%), 9/9 (100%) and 2/9 (22%) cases respectively. In invasive ductal adenocarcinoma of the pancrease (7 cases), ras, c-erbB-2, p53 and Rb gene products were expressed in 3/7 (43%), 6/7 (86%), 2/7 (29%) and 3/ & (43%) cases respectively. CEA, CA19-9 and DUPAN-2 were expressed in 7/7 (100%), 7/7 (100%) and 6/7 (86%) cases, respectively. The extent and intensity of the expression of these antigens was greater in invasive ductal adenocarcinomas. These data suggest that activation of ras and c-erbB-2 oncogenes and inactivation of Rb anti-oncogene may contribute to the development and progression of intraductal papillary-mucinous tumours of the pancreas and that there is neo-expression of CEA and DUPAN-2 during the development and progression of these tumours.  相似文献   
16.
Priming effect of RANTES on eosinophil oxidative metabolism   总被引:1,自引:0,他引:1  
Background RANTES has been shown to possess chemotactic activity for eosinophils, which have also been considered to play a role in allergic inflammation through reactive oxygen species. Thus, in this study, we examined the effect of RANTES on radical oxygen products from eosinophils.
Methods Purified eosinophils by CD16-negative selection or an eosinophilic cell line (EoL-1) were incubated with or without RANTES (2.5 x 10−6). To the mixture of eosinophils and luminol, calcium ionophore (A23187) or opsonized zymosan (OZ) was added, and radical oxygen products were determined by luminol-dependent chemiluminescence for 600 s.
Results Eosinophil-mediated radical oxygen products of untreated eosinophils produced with A23187 gave a peak value of 14.09 + 2.40 (mean±SE, n = 12) relative light units (RLU) and an integrated value of 3232.20 + 513.09 RLU. However, with treatment with RANTES, a peak value of 18.66 + 2.40 RLU and an integrated value of 5301.05 ±561.02 RLU were obtained. Eosinophil oxidative metabolism-induced A23187 or OZ was apparently augmented by the preincubation with RANTES. In addition, the radical oxygen products of EoL-1 showed similar results.
Conclusions Thus, we concluded that RANTES may play an important role the pathogenesis of allergic inflammation through its involvement in eosinophil activation, as evidenced by oxygen products, as well as in selective eosinophil infiltration as selective eosinophil chemoattractant.  相似文献   
17.
The present study investigated how variations in coronary vascular resistance and metabolic demand affected myocardial capillary diffusion capacity. Hearts from Wistar rats were perfused with Krebs-Henseleit-albumin buffer in a Langendorff preparation, where heart rate (HR), contractility (dP/dtmax) and myocardial oxygen consumption (MVO2) were recorded continuously. Myocardial capillary diffusion capacity was measured as the permeability surface area product (PS) for Cr-EDTA and vitamin B12 by the single injection colorimetric indicator dilution method. After base-line recordings without drugs, angiotensin II + arginine-vasopressin was infused, which increased coronary vascular resistance by 90%, stimulated HR by 11%, decreased dP/dtmax by 21% and reduced MVO2 by 4%. PSCr-EDTA and PSB12, decreased by 24 and 27%, respectively, leaving the ratio PSCr-EDTA/PSB12 unchanged indicating unaltered capillary permeability. Moreover, the reductions in MVO2 and PS correlated significantly. During vasodilation: (1) nitroprusside-NA stimulated HR by 7% and decreased dP/dtmax by 14%; (2) adenosine reduced dP/dtmax by 37% and decreased MVO2 by 9%; and (3) isoproterenol increased HR, dP/dtmax and MVO2 by 53, 76 and 9%, respectively. However, all three vasodilators reduced PSCr-EDTA and PSB12 in parallel by 7–25% leaving PSCr-EDTA/PSB12 unchanged. Thus, maximal estimated diffusion capacities were obtained during spontaneous coronary vascular tone, most likely reflecting maximal capillary recruitment in the Krebs-Henseleit-albumin perfused heart. The derecruiting effects of the vasoconstrictors were partly overridden by metabolic factors, while the reductions of PS after vasodilation more likely were due to increased heterogeneity in coronary flow.  相似文献   
18.
Sixteen plant-derived or synthetic coumarins with different patterns of substitution were tested for their capacity to modify A23187-induced synthesis of leukotriene B4 and thromboxane B2 via the 5-lipoxygenase and cyclooxygenase pathways of arachidonate metabolism in rat peritoneal exudate leukocytes. Five of the 16 coumarins inhibited LTB4 production: all containortho-dihydroxy substitutions (approximate IC50 values 8–100 M). The mechanism is likely to depend upon a combination of the coumarins' iron-chelating and iron ion-reducing abilities, properties which also confer beneficial activities of these compounds as scavengers of reactive oxygen species (Payá et al., Biochem. Pharmacol.44, 205–214 (1992)). Inhibition of the cyclooxygenase pathway was only demonstrated by one compound, 5,7-dihydroxy-4-methylcoumarin, which did not inhibit 5-lipoxygenase, indicating that the cyclooxygenase inhibitory mechanism is different. Similar effects of the active coumarins were obtained using arachidonic acid as substrate for rat leukocyte eicosanoid generation, confirming that they act at the 5-lipoxygenase/cyclooxygenase level. The same profile of activity was also shown when the coumarins were tested against 5-lipoxygenase in human polymorphonuclear neutrophils. Taken together, these antioxidant and anti-eicosanoid properties of coumarins could be exploited for the design of potentially valuable non-toxic anti-inflammatory agents for treating diseases in which eicosanoid generation and the production of reactive oxygen species are involved.  相似文献   
19.
Fishery products are the main source of dietary n-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA). Following the European Commission’s request to address the risks and benefits of seafood consumption, and taking into account the great variability of nutrient and contaminant levels in fishery products, the present work aims to estimate the n-3 LC-PUFA provided per serving of selected fishes, shrimps and mollusks that are commonly consumed in Spain. This would enable the establishment of a risk–benefit analysis of fish consumption and provide recommendations for fish intake to comply with nutritional guidelines of n-3 LC-PUFA intake. We confirmed high variation in the pattern and contents of fatty acids for different species. n-6 PUFA were minor fatty acids, whereas palmitic (C16:0), oleic (C18:1 n-9), and mainly eicosapentaenoic (C20:5 n-3) and docosahexaenoic (C22:6 n-3) acids were the major fatty acids in the sample. Therefore, consumption of 2–3 servings per week of a variety of fishery products may contribute to compliance with the recommended daily n-3 LC-PUFA intake while maintaining an adequate balance to avoid contaminant-derived potential risks (metals and others). Taking the fatty acid content of fishery products described in this study into consideration, it is advisable to include one serving of fatty fish per week in order to meet recommended n-3 LC-PUFA levels.  相似文献   
20.
Due to the constantly increasing number of cases, prostate cancer has become one of the most important health problems of modern societies. This review presents the current knowledge regarding the role of nutrients and foodstuff consumption in the etiology and development of prostate malignancies, including the potential mechanisms of action. The results of several in vivo and in vitro laboratory experiments as well as those reported by the clinical and epidemiological research studies carried out around the world were analyzed. The outcomes of these studies clearly show the influence of both nutrients and food products on the etiology and prevention of prostate cancer. Consumption of certain nutrients (saturated and trans fatty acids) and food products (e.g., processed meat products) leads to the disruption of prostate hormonal regulation, induction of oxidative stress and inflammation, and alteration of growth factor signaling and lipid metabolism, which all contribute to prostate carcinogenesis. On the other hand, a high consumption of vegetables, fruits, fish, and whole grain products exerts protective and/or therapeutic effects. Special bioactive functions are assigned to compounds such as flavonoids, stilbenes, and lycopene. Since the influence of nutrients and dietary pattern is a modifiable risk factor in the development and prevention of prostate cancer, awareness of the beneficial and harmful effects of individual food ingredients is of great importance in the global strategy against prostate cancer.  相似文献   
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