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81.
Leptin is an adipocyte-secreted hormone which plays a key role in energy homeostasis. Recent “proof of concept” studies involving leptin administration to humans support its critical role in regulating energy homeostasis, neuroendocrine and immune function as well as insulin resistance in states of energy/ caloric deprivation. Moreover, interventional studies in leptin deficient children and observational studies in normal girls and boys support a role for leptin as a permissive factor for the initiation of puberty in children. The potential clinical usefulness of leptin in several disease states in children and adolescents, including hypothalamic amenorrhea, eating disorders and syndromes of insulin resistance is still under investigation.  相似文献   
82.
We tested whether corticosterone replacement causes increased sucrose drinking in adrenalectomized (ADX) rats compared to sham-ADX (sham) rats. ADX rats given high doses of corticosterone drank as much sucrose as sham rats, whereas at three lower doses of corticosterone, drinking was similar between groups and was only approximately 40% of that ingested by shams. Compared to sham rats, ADX rats drinking saline, or saline and saccharin, gain weight more slowly, contain less white adipose tissue, and have higher sympathetic outflow as assessed by uncoupling protein content in brown adipose tissue. Allowing sucrose as well as saline to drink restored all of these variables to normal in ADX rats with no- or low-corticosterone. All endpoints from sucrose-drinking ADX rats with no-or low-corticosterone were indistinguishable from those in water-drinking shams. By contrast, sucrose-drinking ADX rats that were given high doses of corticosterone exhibited the usual catabolic effects of corticosterone on body weight gain and, unlike sucrose-drinking shams, were obese. We conclude that (i) high corticosterone stimulates the potability of sucrose and inhibits sympathetic stimulation of uncoupling protein; (ii) sucrose, without corticosterone, normalizes metabolic deficits in ADX rats probably through actions mediated both peripherally and by the central nervous system; and (iii) ADX rats have a distinct sucrose appetite.  相似文献   
83.
"双固一通"针刺法对糖尿病大鼠血浆神经肽Y的影响   总被引:8,自引:0,他引:8  
目的观测"双固一通"针剌法针刺对糖尿病大鼠血浆NPY的影响.方法180~220g Wistar大鼠73只,13只为正常对照(A组),另60只行链脲左菌素腹腔注射造模,造模成功的大鼠随机分为模型组(B组)、"一通"针刺治疗组(C组)、"双固一通"针刺治疗组(D组)和常规针刺治疗组(E组),治疗2个疗程后用放射免疫分析法检测各组血浆胰岛素和NPY,用血糖仪检测各组血糖.结果C组使糖尿病大鼠血糖水平有降低趋势,NPY水平上升,但与模型组比较,无显著性差异(P>0.05).D组和E组均明显降低糖尿病大鼠的血糖水平(P<0.05),使糖尿病大鼠升高的血浆NPY水平降低(P<0.05),对降低的胰岛素水平有升高的趋势,但与治疗前相比,无显著性差异(P>0.05),在降低NPY水平方面,D组效果更好(P<0.05).结论双固一通针刺法降低血糖的同时,使糖尿病大鼠的NPY水平降低,这可能是其防治糖尿病血管并发症的机制之一.  相似文献   
84.
张山 《循证护理》2022,(2):185-188
从认知负荷的定义、分类、测量方法以及在医疗护理领域中的应用等方面对国外最新研究进展进行综述,旨在为我国医院管理者在改善医护人员实施治疗与护理措施时认知负荷的水平发挥积极作用提供理论依据。  相似文献   
85.
Robotic milling has broad application prospects in many processing fields. However, the milling performance of a robot in a certain posture, such as in face milling or grooving tasks, is extremely sensitive to process parameters due to the influence of the serial structure of the robot system. Improper process parameters are prone to produce machining defects such as low surface quality. These deficiencies substantially decrease the further application development of robotic milling. Therefore, this paper selected a certain posture and carried out the robotic flat-end milling experiments on a 7075-T651 high-strength aeronautical aluminum alloy under dry conditions. Milling load, surface quality and vibration were selected to assess the influence of process parameters like milling depth, spindle speed and feed rate on the milling performance. Most notably, the contribution ratio based on the analysis of variance (ANOVA) was introduced to statistically investigate the relation between parameters and milling performance. The obtained results show that milling depth is highly significant in milling load, which had a contribution ratio of 69.25%. Milling depth is also highly significant in vibration, which had a contribution ratio of 51.41% in the X direction, 41.42% in the Y direction and 75.97% in the Z direction. Moreover, the spindle speed is highly significant in surface roughness, which had a contribution ratio of 48.02%. This present study aims to quantitatively evaluate the influence of key process parameters on robotic milling performance, which helps to select reasonable milling parameters and improve the milling performance of the robot system. It is beneficial to give full play to the advantages of robots and present more possibilities of robot applications in machining and manufacturing.  相似文献   
86.
Cannabidiol (CBD) is widely available and marketed as having therapeutic properties. Over-the-counter CBD is unregulated, many of the therapeutic claims lack scientific support, and controversy exists as to the safety of CBD-liver interaction. The study aims were to compare the pharmacokinetics of commercial CBD and CBD metabolites following the ingestion of five different CBD formulations, determine the influence of CBD on food induced thermogenesis, determine the influence of food on CBD pharmacokinetics, and determine the influence of CBD on markers of liver function. Fourteen males (body mass index ≥ 25 kg/m2) were studied in a placebo-controlled, randomized, crossover design. On five occasions, different CBD formulations were ingested (one per visit). On two additional occasions, CBD or placebo was ingested following a meal. CBD servings were standardized to 30 mg. Considerable pharmacokinetic variability existed between formulations; this pharmacokinetic variability transferred to several of the metabolites. CBD did not influence food induced thermogenesis but did favorably modify early insulin and triglyceride responses. Food appreciably altered the pharmacokinetics of CBD. Finally, CBD did not evoke physiologically relevant changes in markers of liver function. Collectively, these data suggest that consumers should be aware of the appreciable pharmacokinetic differences between commercial CBD formulations, CBD is unlikely to influence the caloric cost of eating but may prove to be of some benefit to initial metabolic responses, consuming CBD with food alters the dynamics of CBD metabolism and increases systemic availability, and low-dose CBD probably does not represent a risk to normal liver function.  相似文献   
87.
Sentinox (STX) is an acid-oxidizing solution containing hypochlorous acid in spray whose virucidal activity against SARS-CoV-2 has been demonstrated. In this paper, results of a randomized controlled trial (RCT) on the efficacy of STX in reducing viral load in mild COVID-19 patients (NCT04909996) and a complementary in vitro study on its activity against different respiratory viruses are reported. In the RCT, 57 patients were randomized (1:1:1) to receive STX three (STX-3) or five (STX-5) times/day plus standard therapy or standard therapy only (controls). Compared with controls, the log10 load reduction in groups STX-3 and STX-5 was 1.02 (p = 0.14) and 0.18 (p = 0.80), respectively. These results were likely driven by outliers with extreme baseline viral loads. When considering subjects with baseline cycle threshold values of 20–30, STX-3 showed a significant (p = 0.016) 2.01 log10 reduction. The proportion of subjects that turned negative by the end of treatment (day 5) was significantly higher in the STX-3 group than in controls, suggesting a shorter virus clearance time. STX was safe and well-tolerated. In the in vitro study, ≥99.9% reduction in titers against common respiratory viruses was observed. STX is a safe device with large virucidal spectrum and may reduce viral loads in mild COVID-19 patients.  相似文献   
88.
In this study, we evaluated whether the digital program Vitadio achieves comparable results to those of an intensive in-person lifestyle intervention in obesity management. This is a 12-month prospective, randomized controlled trial. Obese patients with insulin resistance, prediabetes or type 2 diabetes were included. The intervention group (IG) used Vitadio. The control group (CG) received a series of in-person consultations. Body weight and various metabolic parameters were observed and analyzed with ANOVA. The trial is ongoing and the presented findings are preliminary. Among 100 participants (29% men; mean age, 43 years; mean BMI, 40.1 kg/m2), 78 completed 3-month follow-up, and 51 have completed the 6-month follow-up so far. Participants significantly (p < 0.01) reduced body weight at 3 months (IG: −5.9 ± 5.0%; CG: −4.2 ± 5.0%) and 6 months (IG: −6.6±6.1%; CG: −7.1 ± 7.1%), and the difference between groups was not significant. The IG achieved favorable change in body composition; significant improvement in TAG (−0.6 ± 0.9 mmol/l, p < 0.01), HDL (0.1 ± 0.1%, p < 0.05), HbA1c (−0.2 ± 0.5%, p < 0.05) and FG (−0.5 ± 1.5 mmol/l, p < 0.05); and a superior (p = 0.02) HOMA-IR reduction (−2.5 ± 5.2, p < 0.01). The digital intervention achieved comparable results to those of the intensive obesity management program. The results suggest that Vitadio is an effective tool for supporting patients in obesity management and diabetes prevention.  相似文献   
89.
大黄素、小檗碱对HepG2细胞胰岛素抵抗的预防作用研究   总被引:1,自引:0,他引:1  
目的:研究大黄素、小檗碱对HepG2细胞产生胰岛素抵抗的预防作用及机制。方法:首先用MTT法筛选大黄素、小檗碱作用于HepG2细胞的实验浓度,然后用软脂酸诱导HepG2细胞,同时分别加入大黄素、小檗碱干预,并设正常组、对照组进行比较,通过葡萄糖氧化酶法、蒽酮法、RT-PCR法,观察大黄素、小檗碱对HepG2细胞上糖代谢及瘦素长型受体、短型受体mRNA表达水平的影响。结果:对照组成为具有胰岛素抵抗的HepG2细胞,且细胞上瘦素长型及短型受体mRNA的表达水平较正常纽显著下降(P〈0.01);而大黄素、小檗碱组培养液中葡萄糖含量、细胞内糖原含量以及细胞上瘦素长型及短型受体mRNA的表达水平较正常组无明显改变(P〉0.05)。结论:大黄素、小檗碱均能预防HepG2细胞产生胰岛素抵抗,这一作用与它们影响HepG2细胞上糖代谢及瘦素受体mRNA表达水平有关。  相似文献   
90.
目的:为探索西拉普利治疗高血压病疗效及其对胰岛素抗药性的影响。方法:采用随机对照法对原发性高血压30例(男性16例,女性14例,年龄48±s10a),用西拉普利2.5~5.0mg/d,疗程4wk。对照组为20例(男性11例,女性9例;年龄52±7a),用氢氯噻嗪25~50mg/d,疗程4wk。结果:西拉普利和氢氯噻嗪都有明显降压作用,但只有西拉普利有改善胰岛素抗药性的效应。结论:西拉普利治疗高血压病人有改善胰岛素抗药性的作用,对糖代谢起良好的影响。  相似文献   
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