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We briefly describe the hormonal responses associated with stress and provide evidence that endogenous and exogenous opioids have "antistress" hormonal profiles. We present data which indicate that analgesic nitrous oxide produces a typical opioid hormonal response, viz. increased prolactin and decreased cortisol levels. There was no significant change in ACTH levels despite the fall in cortisol. We present evidence which supports the hypothesis that the antistress hormonal effects of opioids and analgesic nitrous oxide are mediated by uncoupling the adrenal gland from hypothalamico-pituitary stimulation. It would appear that the opioid system acts antagonistically to the adrenocortical system in stress. We propose that any method stimulating the opioid system optimally may have the antistress effects.  相似文献   
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目的 真核表达人呼吸道合胞病毒(human respiratory syncytial virus,SV)融合蛋白(fusion protein,),并完成蛋白纯化及纯度测定.方法 根据编码F蛋白的基因序列设计引物,CR方法扩增出3'端带His标签的F基因序列,克隆入pGEM-T-easy载体,经核酸序列分析后,进一步克隆到pcDNA3.1( )真核表达载体,限制性内切酶鉴定,用脂质体Lipofectamine2000转染COS-7细胞,2 h后再用Westem blot检测目的蛋白的表达.Ni柱亲和层析纯化COS-7细胞表达的F蛋白,高效毛细管电泳分析纯化后蛋白纯度.结果 核酸序列分析证实获得带His标签的RSV F基因序列,没有发生无义突变.转染COS-7细胞后,利用Western blot方法检测到F蛋白的特异性条带,纯度达99%以上.结论 初步建立了真核表达RSV F蛋白的纯化方法,为进一步优化RSV F蛋白制备条件及单克隆抗体及诊断试剂等研究奠定了基础.  相似文献   
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 目的:探讨上皮样血管瘤(EH)的临床及组织病理学特征。 方法:回顾性分析16例已确诊患者的临床及病理资料,并对相关文献进行综述。 结果:16例患者中女8例,男8例;平均年龄(45.44±12.52)岁;病程3个月~20年;皮损主要表现为红色至暗红色丘疹、结节,可伴瘙痒和糜烂,好发于头皮、耳部,其中发生在头部10例、耳部5例、外阴1例;皮损单发者5例,多发者11例。皮损组织病理学检查均具有典型的血管增生,管壁增厚,内皮细胞呈上皮样突向管腔,管周大量淋巴细胞及嗜酸性粒细胞浸润。结论:上皮样血管瘤少见,诊断需要临床与病理密切结合。加强对该病的认识,可避免误诊误治。  相似文献   
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A boy with the dysmorphic features of Noonan's syndrome and pulmonary valve stenosis who had evidence of hypoparathyroidism and abnormal T lymphocyte numbers in the neonatal period is reported. He had a normal karyotype but molecular analysis revealed a submicroscopic deletion within chromosome 22q11, the region deleted in DiGeorge syndrome. Thus this child has both Noonan's syndrome and DiGeorge syndrome; 22q11 is a candidate region for a gene defective in Noonan's syndrome.  相似文献   
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This paper experimentally evaluates the “imaginary cardiac vector” hypothesis, that the cardiac vector is not a real vector. We have previously shown on theoretical grounds that the basis of the cardiac vector is invalid in that Einthoven used scalar, not vector, procedures. Attempts by subsequent workers to compensate for the theoretical flaws have not succeeded. The concept of the “cardiac vector” which they have invented has the dimensions of an imaginary entity. Experimental measurement of isopotential maps derived from dipoles in a volume conductor demonstrates that these dipoles do not summate vectorially. Isopotential maps of the thoracic surface confirm that this applies to the human ECG.An imaginary “man-frog” cardiac vector loop is demonstrated using a lead from a man and a lead from a frog. This illustrates that the “imaginary cardiac vector” is a tenable concept. Finally, a crucial test of the hypothesis is reported which demonstrates that exercise causes deviations of the so-called cardiac vector in opposite directions, simultaneously, in different VCG lead systems. Since a physical entity can only be in one place and move in one direction at a particular instant, this experiment invalidates the “real cardiac vector” hypothesis. This strongly suggests that the cardiac vector is a brilliant, but imaginary, construction with immense clinical value, especially in the interpretation of the sequence of depolarization. Nevertheless, it obstructs analysis of the real basis of the electricity of the heart.  相似文献   
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Objectives: Patients without a history of diabetes mellitus may be incidentally found to be hyperglycemic in the emergency department (ED). If the hyperglycemia is due to undiagnosed diabetes, then an opportunity for detection exists. Hemoglobin A1c (HbA1c) provides a weighted average of blood glucose levels over the past several months; high HbA1c levels could indicate diabetes. The objective of this study was to determine whether hyperglycemia in ED patients without a history of diabetes was associated with higher HbA1c levels.
Methods: This was a prospective nonconsecutive case series of adults aged 18 years or older presenting to the ED with acute illness for whom a plasma glucose sample was drawn for clinical management. A history of diabetes/hyperglycemia or current symptoms of diabetes excluded patients. HbA1c levels were analyzed for a glucose cutoff of 110 mg/dL; the data were further analyzed using additional glucose cutoffs. Based on the Third National Health and Nutrition Examination Survey outpatient screening data, an HbA1c level ≥6.2% was considered elevated (sensitivity of 63% and specificity of 97% for identifying diabetes).
Results: There were 541 patients enrolled; the glucose level correlated with the HbA1c level ( r = 0.60, p < 0.001). Among the 331 patients with a glucose level ≥110 mg/dL, 22.4% had an elevated HbA1c level; among the 210 patients with a glucose level < 110 mg/dL, 7.6% had an elevated HbA1c level. There were few patients ( n = 13) with a glucose level ≥200 mg/dL, but most (85%) had an elevated HbA1c level. Among the 140 patients with a mildly elevated glucose level (110–125 mg/dL), 16.4% had an elevated HbA1c level.
Conclusions: Elevated HbA1c levels are found in ED patients with elevated random plasma glucose values. ED patients with hyperglycemia may warrant referral for diabetes testing.  相似文献   
8.
Aim: To compare the efficacy and safety of monotherapy with sitagliptin and metformin in treatment‐naïve patients with type 2 diabetes. Methods: In a double‐blind study, 1050 treatment‐naïve patients (i.e. not taking an antihyperglycaemic agent for ≥16 weeks prior to study entry) with type 2 diabetes and an HbA1c 6.5–9% were randomized (1:1) to treatment with once‐daily sitagliptin 100 mg (N = 528) or twice‐daily metformin 1000 mg (N = 522) for 24 weeks. Metformin was up‐titrated from 500 to 2000 mg per day (or maximum tolerated daily dose ≥1000 mg) over a period of 5 weeks. The primary analysis used a per‐protocol (PP) approach to assess whether sitagliptin was non‐inferior to metformin based on HbA1c change from baseline at week 24. Non‐inferiority was to be declared if the upper boundary of the 95% confidence interval (CI) for the between‐group difference in this endpoint was <0.40%. Results: From a mean baseline HbA1c of 7.2% in the PP population, HbA1c change from baseline was ?0.43% with sitagliptin (n = 455) and ?0.57% with metformin (n = 439). The between‐group difference (95% CI) was 0.14% (0.06, 0.21), thus confirming non‐inferiority. Baseline HbA1c influenced treatment response, with larger reductions in HbA1c observed in patients with baseline HbA1c≥8% in the sitagliptin (–1.13%; n = 74) and metformin (–1.24%; n = 73) groups. The proportions of patients at week 24 with HbA1c values at the goals of <7 or <6.5% were 69 and 34% with sitagliptin and 76 and 39% with metformin, respectively. Fasting plasma glucose changes from baseline were ?11.5 mg/dL (–0.6 mmol/l) and ?19.4 mg/dl (–1.1 mmol/l) with sitagliptin and metformin, respectively (difference in LS mean change from baseline [95% CI] = 8.0 mg /dl [4.5,11.4]). Both treatments led to similar improvements from baseline in measures of homeostasis model assessment‐β cell function (HOMA‐β) and insulin resistance (HOMA‐IR). The incidence of hypoglycaemia was 1.7% with sitagliptin and 3.3% with metformin (p = 0.116). The incidence of gastrointestinal‐related adverse experiences was substantially lower with sitagliptin (11.6%) compared with metformin (20.7%) (difference in incidence [95% CI] = ?9.1% [?13.6,?4.7]), primarily because of significantly decreased incidences of diarrhoea (3.6 vs. 10.9%; p < 0.001) and nausea (1.1 vs. 3.1%; p = 0.032). Body weight was reduced from baseline with both sitagliptin (LS mean change [95% CI] = ?0.6 kg [?0.9,?0.4]) and metformin (–1.9 kg [–2.2, ?1.7]) (p < 0.001 for sitagliptin vs. metformin). Conclusions: In this 24‐week monotherapy study, sitagliptin was non‐inferior to metformin in improving HbA1c in treatment‐naïve patients with type 2 diabetes. Although both treatments were generally well tolerated, a lower incidence of gastrointestinal‐related adverse experiences was observed with sitagliptin.  相似文献   
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We measured total respiratory system compliance (Crs) before and after instilling 25 mg artificial surfactant in 1 ml saline down the endotracheal tube of preterm babies requiring resuscitation at birth, and compared results with data from 6 similar babies receiving saline only. Surfactant did not produce a significant improvement in Crs.  相似文献   
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