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Ketanserin, a recently developed 5-HT2 receptor antagonist, competitively and selectively blocks the vasoconstrictor activity of 5-hydroxytryptamine (serotonin). We explored a possible contribution of serotonin to augmented vascular tone in patients with severe heart failure, using intravenous and oral formulations of ketanserin. When administered intravenously (10 mg bolus, 4 mg/hr infusion for +/- 40 min) to 10 patients with congestive heart failure (NYHA III or IV) secondary to congestive cardiomyopathy (n = 8) or ischemic heart disease (n = 2), the drug produced a significant increase in cardiac output (rest 24%, p less than 0.001; exercise 19%, p less than 0.01) which was accompanied by a fall in systemic arterial pressure (rest 7%, p less than 0.001; exercise 10%, p less than 0.05) and pulmonary wedge (rest 17%, p less than 0.05; exercise 23%, p less than 0.001) pressure. Calculated systemic vascular resistance (SVR, rest 27%, p less than 0.001; exercise 23%, p less than 0.05) decreased significantly. No significant hemodynamic changes were observed when 40 mg of ketanserin was administered orally to the same group of patients. Plasma catecholamines (norepinephrine, NEP:epinephrine, EP:dopamine) were measured before and after ketanserin at rest and during exercise. Baseline NEP levels were markedly elevated at rest and during exercise in all patients (rest: 878 +/- 381 ng/mL, exercise: 1453 +/- 697 ng/mL). Baseline EP levels were within normal limits. Ketanserin did not produce any change in catecholamine concentration.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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BackgroundFew studies evaluate the impact of unhealthy alcohol and drug use on the risk and severity of postoperative outcomes after upper gastrointestinal and pancreatic oncologic resections.MethodsThe National Inpatient Sample was queried to identify patients undergoing total gastrectomy, esophagectomy, total pancreatectomy, and pancreaticoduodenectomy between 2012 and 2015. Unhealthy alcohol and drug use was assessed by the International Classification of Diseases, Ninth Revision, and National Inpatient Sample coder designation. Multivariable regression was used to identify associations between alcohol and drug use and postoperative complication, duration of stay, hospital cost, and mortality.ResultsIn the study, 59,490 patients met inclusion criteria; 2,060 (3.5%) had unhealthy alcohol use; 1,265 (2.1%) had unhealthy drug use. Postoperative complication rates were higher in patients with alcohol and drug use than in abstainers (67.5% vs 62.8% vs 57.2%; P < .01). On multivariable regression, alcohol use was independently associated with increased risk of a nonwithdrawal complication (odds ratio 1.33 [1.05, 1.68]), and alcohol and drug use were independently associated with increased length of stay (1.54 [0.12, 2.96]) and 2.22 [0.90, 3.55] days) and cost ($5,471 [$60, $10,881] and $4,022 [$402, $7,643]), but not mortality.ConclusionUnhealthy substance use is associated with increased rates of postoperative complications, prolonged length of stay, and costs in patients undergoing major upper gastrointestinal and pancreatic oncologic resections. Screening and abstinence interventions should be incorporated into the preoperative care pathways for these patients.  相似文献   
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Non-small cell lung cancer (NSCLC) is one of the most common types of cancer in the world and has a 5-year survival rate of ~20%. Immunotherapies have shown promising results leading to durable responses, however, they are only effective for a subset of patients. To determine the best therapeutic approach, a thorough and in-depth profiling of the tumour microenvironment (TME) is required. The TME is a complex network of cell types that form an interconnected network, promoting tumour cell initiation, growth and dissemination. The stroma, immune cells and endothelial cells that comprise the TME generate a plethora of cytotoxic or cytoprotective signalling pathways. In this review, we discuss immunotherapeutic targets in NSCLC tumours and how the TME may influence patients' response to immunotherapy.  相似文献   
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Hamartomas are tumour like malformations which are due to a developmental anomaly. They are most commonly seen in the spleen, lungs, liver and kidney, they are rare in the head and neck region. A rare case of Hamartoma of the soft tissues of the face in a 13 year old boy is reported.  相似文献   
6.
Traditional Persian medicine (TPM) proposes a different viewpoint to the chronic diseases. Diagnosis and implemented treatment are based on individual differences among patients. Constipation or Ea''teghal-e-batn is a condition in which the patient develops difficult or painful defecation. Based on TPM concepts, the first digestion step starts from halq (oral cavity), and ends via defecation from the maq''ad (anus). Avicenna believed that four faculties, ha''zemeh (digestive), ja''zebeh (absorptive), ma''sekeh (retentive) and da''fe''eh (propulsive), are involved in the process of digestion and absorption of the ingested food and expelling the waste materials. The bowel movement and appearance of the stool is a measure for evaluating the gastrointestinal healthy function. Defecation should be with no pain and fecal material should have no burning and acuity. Low food intake or foods with dry temperament, dryness of gastrointestinal tract, diaphoresis and heavy exercise as well as intestine sensory loss were discussed as main causes of constipation. Management of constipation in TPM includes dietary schemes, oil massages and subsequently simple herbal medicines. According to TPM theories, the first step in treating a disease is the elimination of disease causes (asbab e-maraz) and also providing the causes of health (asbab-e-sehhat). Health care providers should know the proper condition which the herbal medicines should be administered in and be able to guide the patients about the benefits and hazards of herbal remedies, commonly used in their living origin.  相似文献   
7.
Pseudoangiomatous stromal hyperplasia (PASH) is a rare benign breast entity scarcely reported in the medical literature. Its pathogenesis, etiology, and optimal treatment are still unknown. PASH tumors have a broad spectrum of clinical presentations and might be mistaken for malignancies. The authors present six patients diagnosed with PASH.  相似文献   
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Although a sleeper makes a great contribution to the lateral resistance of ballasted tracks, in this regard, limited studies have been carried out on the effect of its contact surface with ballast aggregates. The current paper is dedicated to evaluating the effect of sleeper shape on the lateral resistance of ballasted track through discrete element modelling (DEM). For this purpose, firstly, a DEM model was validated based on the experimental results. Then, a sensitivity analysis was undertaken on the effect of the different contact areas that a standard concrete sleeper faces with the crib, shoulder and underlying ballast aggregates on lateral resistance of a single sleeper. As the main result of the current study, a high accurate regression equation for constant weight 319.2 kg and constant density 2500 kg/m3 of the sleepers was fitted between different sleeper contact areas and the maximum lateral resistance of a concrete sleeper for 3.5 mm lateral displacement in ballasted railway tracks. The obtained results showed that the effect of the sleeper’s head area compared to the underlying area of the sleeper and the head area of the sleeper compared to the sleeper’s side area in terms of lateral resistance are 8.2 times and 14.5 times more, respectively.  相似文献   
10.
This work was carried out to explore the compounds of bismuth with carbon using density functional theory (DFT)-based computations. The structures of the compounds BiC, BiC2, BiC3, Bi2C3, BiC5, and Bi2C5 were predicted at a generalized gradient approximation (GGA-PBE) level of theory. The calculations were carried out on the structures in unit cell and supercell geometries in slab and bulk periodicities. The structural and electronic properties of the mentioned compounds were investigated in detail. The calculations of the structures revealed lattice constants of the compounds for cubic unit cell as 212.2 pm for BiC, 176.9 pm for BiC2, 240.5 pm for BiC3, 232.4 pm for Bi2C3, and 354.5 pm for Bi2C5. The compounds BiC, BiC2, BiC3, BiC5, and Bi2C5 were found to be metallic, whereas Bi2C3 exhibited semiconducting character with a band gap of 0.305 eV. This work provides an initial framework for preparing new 2D materials from BixCy.  相似文献   
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