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71.
AIMS: Metabolic responses to manipulation of the plasma free fatty acid (FFA) concentration were assessed in six healthy men via cross-over design to determine whether FFAs independently influence insulin sensitivity. METHODS: Intramyocellular lipid (IMCL) was measured by proton magnetic resonance spectroscopy and insulin sensitivity via frequently sampled intravenous glucose tolerance test (IVGTT) after 67 h of two identical low carbohydrate/high fat (LC) diets which were used to elevate IMCL and plasma FFAs. To uncouple the influence of FFAs and IMCL on insulin sensitivity, FFAs were suppressed 30 min prior to and during IVGTT in one treatment [LC + nicotinic acid (NA)] by NA ingestion. RESULTS: Vastus lateralis IMCL was significantly elevated in LC (13.3 +/- 1.1 x 10(-3)) and LC + NA (13.5 +/- 1.1 x 10(-3)) (P < 0.01 for both), but was not different between conditions (P > 0.05). Plasma FFAs were raised in LC (0.79 +/- 0.08 mmol/l) and LC + NA (0.80 +/- 0.11 mmol/l) (P < 0.01 for both) and were significantly reduced by NA ingestion prior to (0.36 +/- 0.05 mmol/l, P < 0.01) and during IVGTT (P < 0.05) in LC + NA. Despite marked differences in plasma FFA availability, insulin sensitivity and glucose tolerance were not different between LC and LC + NA (P > 0.05 for both). CONCLUSIONS: Plasma FFAs appear to exert no immediate effect on insulin sensitivity/glucose tolerance independent of their action on intracellular lipid moieties. Further research is required to elucidate the duration of FFA suppression required to restore insulin sensitivity following lipid-induced insulin resistance.  相似文献   
72.
Sixty women with breast cancer (mean age: 61 years; range 36-78 years) were treated with Epirubicin (4’epi-Dox-orubicin), 60 mg m-2 , as single drug therapy. The drug was administered as 2 hours’ constant rate infusions. The pharmacokinetics of the drug during the first course of treatment was evaluated by measurements of the plasma concentration of Epirubicin at the end of the infusion period. There was a five-fold inter-individual variation of the dose-normalized maximum plasma concentration, which increased with increasing age of the patients. There was no correlation between this pharmacokinetic parameter and degree of obesity.  相似文献   
73.
This study was designed with two purposes: first, to elucidate immunologic mechanisms in different cutaneous reactions, particularly in hypersensitivity to mosquito bites, and, second, to develop a more reliable and safer method of identifying the causative species of mosquito in severe cases. The amounts of IgG, IgG4 and IgE specific to the mosquito salivary gland extract of Aedes albopictus were determined in the sera of 116 volunteers with normal reactions, either immediate or delayed, and 4 patients with severe systemic symptoms caused by mosquito bites. Titers of IgG and IgE in the severe cases were considerably higher than in volunteers with normal reactions, but there were no differences in IgG, titers between the two groups. These results indicate that high titers of IgG and IgE may be involved in development of systemic symptoms in severe cases and verify the possibility of in vitro tests to identify causative species of the mosquito.  相似文献   
74.
Mivazerol is a new and selective α2-adrenoceptor agonist which has demonstrated anti-ischemic effects, both in animals and in patients with myocardial ischemia. In the present study, mivazerol was evaluated for its ability to inhibit the release of catecholamines and serotonin (5-HT) in the hippocampus of freely moving rats, and also was compared to clonidine. In vivo microdialysis in combination with high-performance liquid chromatography (HPLC) was employed. Intravenous administration of mivazerol (8.0 μg/kg) had no effect on basal outflow of norepinephrine (NE), dopamine (DA) and 3,4-dihydroxyphenylacetic acid (DOPAC). In contrast, clonidine (8.5 μg/kg, i.v.) attenuated the basal release of DOPAC, which has been proposed to reflect NE biosynthesis, suggesting that clonidine has an inhibitory effect on NE synthesis. In addition, both mivazerol and clonidine decreased the spontaneous release of 5-HT, which provided further evidence that α2-adrenoceptors in the hippocampus modulate 5-HT. Sixty-min immobilization stress significantly increased the release of NE (177 ± 28%), DA (209 ± 46%) and DOPAC (337 ± 72%). Mivazerol (2.5, 8.0 and 25 μg/kg, i.v.) completely prevented the immobilization stress-induced enhancement of NE, DA and DOPAC, which was equi-effective to clonidine at a dose of 8.5 gmg/kg, i.v. These findings demonstrate that mivazerol has a profound modulatory effect on stress-induced neurotransmitter release in the hippocampus, at dose levels reported to protect against myocardial ischemia.  相似文献   
75.
Chronic rejection (CR) is a major problem in long-term survival in heart transplantation. We analysed whether the occurrence of CR correlates with the incidence of acute rejections (AR) or with characteristics of endomyocardial biopsy-derived cell cultures. CR was diagnosed by annual angiography and defined as all coronary vascular changes. One year after transplantation 24 of the 63 patients had CR (38%). The incidence of AR in CR + and CR — patients was comparable. The patients in both groups had similar individual median percentages of EMB-yielding cell cultures. During the first year the CR — patients had more cultures in which at least 60% of the cells were CD4 + T cells (50% vs 37%, P = 0.05), due to a stronger CD4 predominance in the first 6 months. In the second year the CD4 predominance in the patients diagnosed as CR + after 1 year tended to be higher (P = 0.08). The patients had comparable percentages of cultures predominated by CD8 + T cells, γδ T cells or NK cells, irrespective of the time interval. These results might indicate that CD4 + T lymphocytes play a dual role in the aetiology of CR.  相似文献   
76.
作者研究了高温流化α-化工艺中大米淀粉晶粒、水分、绝干淀粉含量、糊化率、脂肪含量、总氮和可降解氮的变化。研究表明:高温流化α-化后淀粉晶粒消失,成松散片状,比表面积增大,有利于酶的作用;水分含量低于10%,可有效防止淀粉老化和微生物污染;高温流化处理后淀粉糊化率与蒸饭法持平,而脂肪与可降解氮含量均明显下降,为酿造淡爽型酿造酒和提高酿造酒非生物性稳定性创造了机会。该工艺尤其适合在我国以糙米为原料的酿造酒生产中推广应用。  相似文献   
77.
We report experimental evidence for substantial individual differences in the susceptibility to simultaneous colour contrast. Interestingly, we found that not only the general amount of colour induction varies across observers, but also the general shape of the curves describing asymmetric matching data. A simple model based on von Kries adaptation and crispening describes the data rather well when we regard its free parameters as observer specific. We argue that the von Kries component reflects the action of a temporal adaptation mechanism, while the crispening component describes the action of the instantaneous, purely spatial mechanism most appropriately labeled simultaneous colour contrast. An interesting consequence of this view is that traditional ideas about the general characteristics of simultaneous contrast must be considered as misleading. According to Kirschmann’s 4th law, for instance, the simultaneous contrast effect should increase with increasing saturation of the surround, but crispening predicts the converse. Based on this reasoning, we offer a plausible explanation for the mixed evidence on the validity of Kirschmann’s 4th law. We also argue that simultaneous contrast, the crispening effect, Meyer’s effect and the gamut expansion effect are just different names for the same basic phenomenon.  相似文献   
78.
L-精氨酸对高原肺水肿患者血液流变学的作用   总被引:3,自引:0,他引:3  
目的:探讨雾化吸入左旋精氨酸(L-Arg)对高原肺水肿患者血液流变学的影响。方法:在海拔3700m高原,采用氧气驱动雾化吸入L-Arg,治疗高原肺水肿(HAPE)患者9例(L-Arg组),将吸入低浓度一氧化氮(NO)混合气治疗的另外8例高原肺水肿患者(NO组)作对照,分别测定患者的红细胞压积(HCT)、血液粘度(ηb)、血浆粘度(ηp)、还原粘度(ηr)、红细胞刚性指数(IR)、红细胞变形系数(TK)、红细胞聚集系数(VAI)和血栓形成系数(TFL)等血液流变学指标。结果:NO组和L-Arg组治疗后较治愈前ηb、ηp、ηr、VAI、TFL均降低显著(P〈0.05~0.01),而HCT、TK、IR无统计学差异(P〉0.05);NO组与L-Arg组比较,各指标均无统计学差异(P〉0.01)。结论:L-Arg治疗HAPE有效,通过提高NO水平而改善血液循环,且经济简便,易于推广应用。  相似文献   
79.
Aim: Sodium/bicarbonate co‐transport (NBC) has been suggested to have a role in muscle pH regulation. We investigated the presence of NBC proteins in rat and human muscle samples and the fibre type distribution of the identified NBCs. Methods and results: Western blotting of muscle homogenates and sarcolemmal membranes (sarcolemmal giant vesicles) were used to screen for the presence of NBCs. Immunohistochemistry was used for the subcellular localization. The functional test revealed that approximately half of the pH recovery in sarcolemmal vesicles produced from rat muscle is mediated by bicarbonate‐dependent transport. This indicates that the NBCs are preserved in the vesicles. The western blotting experiments demonstrated the existence of at least two NBC proteins in skeletal muscle. One NBC protein (approximately 150 kDa) seems to be related to the kidney/pancreas/heart isoform NBC1, whereas the other protein (approximately 200 kDa) is related to the NBC4 isoform. The two NBC proteins represent the electrogenic isoforms named NBCe1 and NBCe2. Membrane fractionation and immunofluorescence techniques confirmed that the two NBCs are located in the sarcolemmal membrane as well as in some internal membranes, probably the T‐tubules. The two NBCs localized in muscle have distinct fibre type distributions. Conclusions: Skeletal muscle possesses two variants of the sodium/bicarbonate co‐transporter (NBC) isoforms, which have been called NBCe1 and NBCe2.  相似文献   
80.
目的:研究肝细胞癌(hepatocellular carcinoma,HCC)经导管肝动脉化疗栓塞(transcatheter arterial chemoemboli-zation,TACE)后残癌组织细胞黏附分子CD44v6和ICAM-1(intercelluar adhesion molecule-1,ICAM-1)的表达情况。方法:经病理证实的HCC 50例,包括单纯手术切除30例(对照组),TACE术后行Ⅱ期手术切除20例(TACE组)。TACE组患者术前接受1~2次不等的TACE治疗,均按统一规范标准给予化疗药物灌注+栓塞治疗。对标本行免疫组织化学PV-9000染色,其中TACE组取病灶边缘残存肿瘤部分,检测肿瘤组织CD44v6和ICAM-1的表达,将两组结果进行对照分析。结果:对照组和TACE组CD44v6和ICAM-1均有不同程度的表达。对照组CD44v6表达阳性22例(22/30,73.33%),TACE组CD44v6表达阳性13例(13/20,65%),两者间无显著性差异(P>0.05);对照组ICAM-1表达阳性19例(19/30,63.33%),TACE组ICAM-1表达阳性12例(12/20,60%),两者间亦无显著性差异(P>0.05)。对照组和TACE组中CD44v6和ICAM-1表达间均呈正相关(P<0.05)。结论:TACE术后残癌组织CD44v6和ICAM-1仍有较高的表达,TACE并不能有效降低肝癌组织CD44v6和ICAM-1的表达;两者表达呈正相关。  相似文献   
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