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101.
In some parts of the United Kingdom (UK), family doctors (or "general practitioners" as they are called in the UK) are routinely called upon by the emergency medical services (EMS) system to attend road accidents. The doctors are volunteers and travel to the scene of the accident in their own cars. Members of one such general practitioner accident service operating in Mid-Anglia complete an accident report form after attending each incident. In 1983, the Mid-Anglia General Practitioner Accident Service (MAGPAS) received 1,715 calls for medical assistance, and in 95% of these a doctor was sent immediately. Of these calls, 57% were passed to the doctor within one minute of the receipt of the call in the MAGPAS control room, and 78% were relayed within two minutes. This rapid call-out, combined with the close proximity of the local doctor to the accident site, resulted in the doctors arriving ahead of the ambulance in 42% of the calls. A total of 54 patients with airway obstruction were treated by the doctors prior to the arrival of the ambulance. Ninety-nine patients required immediate intravenous fluid replacement in the pre-hospital phase of their medical care. This report suggests that general practitioners in rural areas can play a vital role in the early management of trauma patients, especially in the absence of ambulance personnel trained in advanced life support skills.  相似文献   
102.
Two groups of pigeons with a history of two choice operant drug discrimination tasks (3.0 mg/kg morphine versus 5.6 mg/kg cocaine, and 3.0 mg/kg morphine versus 3.0 mg/kg cocaine, respectively; Swedberg and Järbe 1985) were subjected to three choice tasks in which responses on a third manipulandum were reinforced in the no drug condition. Training drugs generalization gradients in both groups were similar to those normally obtained in two choice drug versus no drug tasks. The salience differences between the training stimuli within the groups observed in the previous two choice task did not differentially affect the three choice discrimination gradients. Tests with novel drugs after the introduction of the no drug condition yielded increased responding to the no drug condition with the exception of the dopamine agonist apomorphine. Results are discussed in terms of a discrimination learning model specifying principles of relative discriminative stimulus control in various discrimination cases.Portions of these data were presented at the International Union of Pharmacology, IUPHAR, 9th International Congress of Pharmacology Satellite Meeting: European Study Group for Internal Stimulus Control by Electrical Stimulation, Drugs and Other Means, ESISC, London, July 29–August 3, 1984 (Swedberg and Järbe 1984). An earlier version of this work appears in the doctoral thesis by the first author (Swedberg 1985).  相似文献   
103.
Summary Changes in tension were monitored isometrically on spiral strips from human saphenous veins obtained during surgical removal of varicose veins. Concentration-response curves for noradrenaline and 5-hydroxytryptamine (5-HT) were established by cumulative administrations, curves for dihydroergotamine were constructed from the mean responses to single concentrations. The use of the antagonists prazosin, yohimbine and pizotifen provided evidence for the existence of both postjunctional 1- and 2-adrenoceptors and for the existence of 5-HT receptors. The venoconstrictor effects of dihydroergotamine were unchanged by prazosin. Yohimbine antagonized both dihydroergotamine and 5-HT at about 60 times higher concentrations than required against noradrenaline whereas pizotifen inhibited responses to both dihydroergotamine and 5-HT at about 100 times lower concentrations than those to noradrenaline.These new results are in contrast to conclusions drawn from animal studies and do not support the suggestion that in man the venoconstrictor activity of dihydroergotamine is mediated through stimulation of -adrenoceptors. The present results strongly suggest that in human saphenous veins the constrictor activity of dihydroergotamine is mediated at least in part through stimulation of 5-HT receptors.  相似文献   
104.
Hazelnuts commonly elicit allergic reactions starting from childhood and adolescence, with a rare resolution over time. The definite diagnosis of a hazelnut allergy relies on an oral food challenge. The role of component resolved diagnostics in reducing the need for oral food challenges in the diagnosis of hazelnut allergies is still debated. Therefore, three electronic databases were systematically searched for studies on the diagnostic accuracy of specific-IgE (sIgE) on hazelnut proteins for identifying children with a hazelnut allergy. Studies regarding IgE testing on at least one hazelnut allergen component in children whose final diagnosis was determined by oral food challenges or a suggestive history of serious symptoms due to a hazelnut allergy were included. Study quality was assessed by the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Eight studies enrolling 757 children, were identified. Overall, sensitivity, specificity, area under the curve and diagnostic odd ratio of Cor a 1 sIgE were lower than those of Cor a 9 and Cor a 14 sIge. When the test results were positive, the post-test probability of a hazelnut allergy was 34% for Cor a 1 sIgE, 60% for Cor a9 sIgE and 73% for Cor a 14 sIgE. When the test results were negative, the post-test probability of a hazelnut allergy was 55% for Cor a 1 sIgE, 16% for Cor a9 sIgE and 14% for Cor a 14 sIgE. Measurement of IgE levels to Cor a 9 and Cor a 14 might have the potential to improve specificity in detecting clinically tolerant children among hazelnut-sensitized ones, reducing the need to perform oral food challenges.  相似文献   
105.
Dietary supplementation with sugar cane derivates may modulate low-density lipoprotein cholesterol (LDL-C) and proprotein convertase subtilisin/kexin type 9 (PCSK9) levels. The purpose of this study was to determine if dietary supplement (DS), containing Octacosanol (20 mg) and vitamin K2 (45 µg), could restore the disrupted physiologic relation between LDL-C and serum PCSK9. Double-blind, randomized, placebo-controlled, single-center study including 87 patients on chronic atorvastatin therapy was conducted. Eighty-seven patients were randomized to receive DS (n = 42) or placebo (n = 45), and followed for 13 weeks. Serum PCSK9 levels, lipid parameters and their relationship were the main efficacy endpoints. The absolute levels of PCSK9 and LDL-C were not significantly different from baseline to 13 weeks. However, physiologic correlation between % change of PCSK9 and % change of LDL-C levels was normalized only in the group of patients treated with DS (r = 0.409, p = 0.012). This study shows that DS can restore statin disrupted physiologic positive correlation between PCSK9 and LDL-C. Elevated PCSK9 level is an independent risk factor so controlling its rise by statins may be important in prevention of cardiovascular events.  相似文献   
106.
The isoforms of lycopene, carotenoids, and their derivatives including precursors of vitamin A are compounds relevant for preventing chronic degenerative diseases such as cardiovascular diseases and cancer. Tomatoes are a major source of these compounds. However, cooking and successive metabolic processes determine the bioavailability of tomatoes in human nutrition. To evaluate the effect of acute/chronic cooking procedures on the bioavailability of lycopene and carotene isoforms in human plasma, we measured the blood levels of these compounds and of the serum antioxidant potential in volunteers after a meal containing two different types of tomato sauce (rustic or strained). Using a randomized cross-over administration design, healthy volunteers were studied, and the above indicated compounds were determined by HPLC. The results indicate an increased bioavailability of the estimated compounds and of the serum antioxidant potential with both types of tomato purée and the subsequently derived sauces (the increase was greater with strained purée). This study sheds light on the content of nutrient precursors of vitamin A and other antioxidant compounds derived from tomatoes cooked with different strategies. Lastly, our study indicates that strained purée should be preferred over rustic purée.  相似文献   
107.
Campylobacteriosis is a disease of worldwide importance, but aspects of its transmission dynamics, particularly risk factors, are still poorly understood. We used data from a matched case-control study of 4,269 men who have sex with men (MSM) and 26,215 controls, combined with national surveillance data on Campylobacter spp., Salmonella spp., and Shigella spp., to calculate matched odds ratios (mORs) for infection among MSM and controls. MSM had higher odds of Campylobacter (mOR 14, 95% CI 10–21) and Shigella (mOR 74, 95% CI 27–203) infections, but not Salmonella (mOR 0.2, 95% CI 0–13), and were less likely than controls to have acquired Campylobacter infection abroad (χ2 = 21; p<0.001). Our results confirm that sexual contact is a risk factor for campylobacteriosis and also suggest explanations for unique features of Campylobacter epidemiology. These findings provide a baseline for updating infection risk guidelines to the general population.  相似文献   
108.
目的 探讨ELABELA(ELA)对妊娠滋养细胞(Bewo细胞)侵袭行为的影响及其可能的作用机制。方法 用siRNA-ELA转染处于对数生长期的Bewo细胞,分为siRNA-ELA转染组,阴性对照组(细胞转染无意义序列)及空白组,细胞转染后于倒置显微镜下观察转染效率,采用实时荧光定量聚合酶链反应(qRT-PCR)检测转染后各组细胞中ELA mRNA表达并明确沉默效率。划痕实验测定各组细胞迁移能力,Transwell实验测定各组细胞的迁移、侵袭能力。蛋白质免疫印迹法检测各组细胞p-AKT、MMP9蛋白表达水平。结果 si-ELA组的ELA表达量明显低于si-NC组及空白组(P<0.001),且si-NC组与空白组差异无统计学意义(P>0.05);siRNA-ELA组细胞的迁移及侵袭能力均明显低于空白组(P<0.01;P<0.01);siRNA-ELA组p-AKT蛋白及MMP9蛋白表达水平明显低于空白组(p-AKT P<0.01;MMP9 P<0.001)。结论 敲低ELA可抑制滋养细胞的侵袭及迁移能力,其机制可能与AKT信号通路有关。  相似文献   
109.
目的探讨改良关节镜下弹性固定 Latarjet 手术治疗伴有明显肩胛盂前缘骨缺损的肩关节复发性前脱位时,移植骨块偏外放置在术后中期对肩关节退变的影响。方法回顾分析 2015 年 1 月—2016 年 11 月收治且符合选择标准的 18 例肩关节复发性前脱位伴肩胛盂前缘骨缺损患者临床资料,均接受改良关节镜下弹性固定 Latarjet 手术。男 12 例,女 6 例;年龄 19~37 岁,平均 26.2 岁。肩关节脱位 4~30 次,平均 8.8 次。病程 8~49 个月,平均 23.8 个月。肩胛盂前缘骨缺损为 20%~29%,平均 25.2%。肩关节不稳定严重指数评分(ISIS)为 7~10 分,平均 7.6 分。肩关节退变 Samilson-Prieto 分级:0 级 13 例,Ⅰ级 3 例,Ⅱ级 2 例。手术前后采用疼痛视觉模拟评分(VAS)、美国肩肘外科协会评分(ASES)、Walch-Duplay 评分、Rowe 评分和肩关节活动度评价临床疗效。影像学观察肩关节退变情况以及移植骨块位置、肩胛盂塑形情况。结果术后患者均获随访,随访时间 55~62 个月,平均 59.6 个月。无血管神经损伤、感染、固定物和移植骨块相关并发症发生,随访期间无肩关节脱位复发和翻修患者。患者均恢复正常生活,17 例重返运动。末次随访时,VAS 评分较术前明显降低,ASES 评分、Walch-Duplay 评分、Rowe 评分明显提高,差异均有统计学意义(P<0.05);肩关节前屈、外展、外展 90° 外旋、0° 外旋和外展 90° 内旋活动度与术前比较,差异均无统计学意义(P>0.05)。术后即刻三维 CT 显示所有移植骨块中心在肩胛盂 En-face 面上位于 3∶30~4∶30(右肩)或 7∶40~8∶20(左肩)位置,无移植骨块过高或过低;在 CT 横断面上相对于肩胛盂偏外 2.3~4.6 mm,平均 3.5 mm。患者术后 36、48 个月及末次随访时的肩关节退变 Samilson-Prieto 分级与术前一致,均未进展。所有移植骨块在术后 24 个月内塑形达稳定,在三维 CT 肩胛盂 En-face 面显示塑形后的肩胛盂外形为与正常肩胛盂相近的正梨形,在 CT 横断面上为与肩胛盂齐平并形成与肱骨头圆形近似的弧形。末次随访时肩胛盂外形与术后 24 个月比较无明显变化。 结论改良关节镜下弹性固定 Latarjet 手术中移植骨块偏外放置,术后中期未出现肩关节退变进展的影像学改变。  相似文献   
110.
目的对肩关节上关节囊重建治疗肩袖损伤适应证和移植物处理方法的研究进展进行综述。方法广泛查阅近年来国内外有关肩关节上关节囊重建治疗肩袖损伤的文献,并进行总结分析。结果肩关节上关节囊重建可以有效恢复肩关节上方稳定性,其手术适应证包括不可修复巨大肩袖撕裂、巨大肩袖撕裂合并肩关节假性麻痹、肩袖分层撕裂以及中或大的肩袖撕裂合并肩袖严重退变。为了获得较好的腱骨愈合以及降低移植物远期再撕裂率,必须选择合适厚度的移植物,并以适当的强度固定移植物并恢复其连续性。结论肩关节上关节囊重建的手术应用已发展至上关节囊加强重建,手术适应证从肩袖实质性巨大缺损扩展至肩袖严重退变。移植物处理是上关节囊重建手术成功的关键。  相似文献   
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