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921.
Two triterpenes 1 and 2 with antiviral activity againstHerpes simplex virus type 1in vitro were isolated fromPrunella vulgaris. Each compound caused a significant reduction in viral cytopathic effect whenvero cells were exposed to them for 72 hours after viral challenge. They were identified asbetulinic acid(1) and 2α, 3α-dihydroxyurs-12-en-28-oic acid(2) on the basis of their spectroscopic properties. The antiviral activity of them was estimated as EC50=30 μg/ml(1) and 8 μg/ml(2), respectively by plaque reduction assay.  相似文献   
922.
We have studied the effect of clonidine pretreatment on cardiovascular responses to various stimuli during craniotomy. Fifty-eight patients (ASA Class I-II), scheduled for supratentorial surgery, were randomly given either oral clonidine, mean dose 3.6 micrograms/kg (n = 28), or oral diazepam, 0.2 mg/kg (n = 30), ninety to one hundred minutes before surgery. Anaesthesia was induced with thiopentone and maintained with nitrous oxide:oxygen, pentazocine and halothane. Pancuronium was used as a neuromuscular blocker. Mean arterial pressure and heart rate were recorded before and after several stimuli. In the clonidine group hypertensive response was significantly less on laryngoscopy (6.5% increases versus 11.2% in the diazepam group), intubation (9.2% versus 16.5%), Mayfield clamp application (14.5% versus 29.91%) and after skin infiltration with lignocaine-adrenaline solution (2.95% versus 5.42%). Heart rate response to laryngoscopy, intubation and skin infiltration was also significantly attenuated in the clonidine group. The sleep dose of thiopentone was smaller in patients pretreated with clonidine. Patients in the diazepam group required more medical intervention. No adverse effect occurred in any patient.  相似文献   
923.
Dyskeratosis congenita has been found to be associated with abnormal immune function. In this study we report a patient with this association. He developed Pneumocystis carinii interstitial pneumonia, and impaired cell mediated immunity was confirmed by the presence of depressed lymphoproliferative responses to in vitro stimulation with mitogen. Enumeration of T cell subsets showed a severely depressed CD4:CD8 ratio (0.38), which is the likely cause for impaired cell mediated immunity. The T cell activation pathway appeared intact, as his T lymphocytes were able to express activation markers (CD25 and HLA-DR) after mitogen stimulation.  相似文献   
924.
925.
The purpose was to measure the effects of postchemotherapy nausea and vomiting (PCNV) on health-related quality of life (HQL) in patients receiving either moderately or highly emetogenic chemotherapy. The study sample consisted of 832 chemotherapy-naive patients with cancer who received either moderately or highly emetogenic chemotherapy as part of multicenter trials of new antiemetics. The patients completed the self-report European Organization for Research and Cancer (EORTC) core Quality of Life Questionnaire (QLQ-C30) before chemotherapy (baseline) and 1 week (day 8) and 2–4 weeks after chemotherapy. They also completed a self-report nausea and vomiting (NV) diary for 5–7 days after chemotherapy. To determine the effects of PCNV on HQL, the change in scores between the baseline and day 8 HQL assessments was calculated for each domain and symptom in the QLQ-C30 and compared in four subgroups of patients: those with both nausea and vomiting, those with nausea but no vomiting, those with no nausea but with vomiting, and those with neither nausea nor vomiting. The group with both nausea and vomiting showed statistically significantly worse physical, cognitive and social functioning, global quality of life, fatigue, anorexia, insomnia and dyspnea as compared to the group with neither nausea nor vomiting (0.0001<P<0.05). Patients with only nausea but no vomiting tended to have less worsening in functioning and symptoms than those having both nausea and vomiting. Increased severity of vomiting (>2 episodes) was associated with worsening of only global quality of life and anorexia as compared with 1–2 episodes of vomiting (0.0001<P<0.01). By 2–4 weeks after chemotherapy all HQL scores had either returned to their baseline levels or were better than baseline. PCNV adversely affects several quality-of-life domains, but patients with only nausea experience less disruption than do those with both nausea and vomiting. Patients with 1–2 episodes of vomiting experience almost the same degree of disruption of HQL as do patients with more than 2 episodes of vomiting.  相似文献   
926.
The purpose of this study was to develop an isolated, pulsatile blood-perfused rat lung model that allows us to evaluate the preserved lung functions. Lungs isolated from Sprague-Dawley rats, were perfused with venous whole blood by either a pulsatile or constant flow. The effuent was continuously deoxygenated with a 95% N2/5% CO2 gas mixture. Airway resistance, lung compliance, elastic work, flow resistive work, pulmonary vascular resistance, and blood gas analysis were assessed. Pressor responses toN G -monomethyl-l-arginine (l-NMMA) were compared between pulsatile and constant blood flow. At a flow of 0.1 ml/g body weight/min, pulsatile perfusion allowed for stable perfusion at least for 2h (mean 162.5±15.1 min) with stable aerodynamic and hemodynamic variables including blood gas tensions, whereas constant perfusion resulted in immediate lung failure. Whenl-NMMA was added to the perfusate, the mean pulmonary artery pressure did not show any change in the constant flow (6.0±2.6% increase), but did show a significant increase in the pulsatile flow (45±11% increase). Pulsatile blood flow reduced the pulmonary vascular resistance relative to the constant flow and allowed for a 2-h perfusion period to evaluate the lung function. The vasorelaxant mechanism in the pulsatile perfusion is related in part to the endothelial-dependent relaxation observed in the nitric oxide pathway. Presented in part at the 79th, Annual Clinical Congress of the American College of Surgeons (ACS) held in San Francisco, CA USA, 1993.  相似文献   
927.
A 70-year-old woman with no previous gastroesophageal surgery gave a 6-month history of dysphagia. Barium studies suggested a diagnosis of achalasia. Esophageal manometry showed absence of peristalsis and a high lower esophageal sphincter pressure. Endoscopy showed a dilated esophagus with food residue, and Barrett's esophagus was present. The association of Barrett's esophagus and achalasia must be rare.  相似文献   
928.
OBJECTIVE: Throughout health care literature, vulnerability is widely accepted as a potential issue for all patients yet the consensus on the meaning of and practical strategies to reduce or manage these 'harmful agents' in the clinical context are rarely offered. Three main themes emerge from the related literature which can be further refined into general terms of; social vulnerability--a person's basic statistical data in relation to their potential for illness; psychological vulnerability--the actual or potential harm to the identity of self and/or other emotional effects such as anxiety or stress caused by the ailment or treatment; and physical vulnerability--which refers to the actual physiological state where an individual is susceptible to further morbidity or mortality. SETTING: Acute care facilities. PRIMARY ARGUMENT: Although there is acknowledgment within the literature that individuals will experience some form of vulnerability when hospitalised, the complexity of what defines vulnerability for individuals causes further problems for patients and health professionals alike. CONCLUSIONS: This paper attempts to define vulnerability within the context of Western health care systems and raises the following issues: all states of vulnerability are accurate and appropriate in the context of the study or incidence alluded to, but further discussion and research is required to achieve a consensus to when, how, why and who is vulnerable. It is this recognition of the potentially differing classifications of vulnerability and the particular contexts that can be used that may assist nurses and other health care professionals with, not only problems associated with a patient's hospitalisation, but in the implementation of appropriate strategies to individual patient's cases.  相似文献   
929.
We examined the relationship between testosterone levels, violent dreams, and REM sleep behavior disorder (RBD) in 31 men with Parkinson's disease (PD): 12 with clinical RBD and 19 without. All PD patients with clinical RBD experienced violent dreams, but none of the 19 non-RBD patients reported violent dreams. While dream content appears to be more aggressive in PD patients with clinical RBD, the presence of violent dreams or clinical RBD is not associated with testosterone levels in men with PD.  相似文献   
930.
Complementary modalities, used alone or in combination with pharmacologic therapies, play an important role in the prevention and management of postoperative nausea and vomiting (PONV) and post discharge nausea and vomiting (PDNV). This article will review the evidence for the effective use of complementary modalities: acupuncture and related techniques, aromatherapy, and music therapy that may be integrated in the perianesthesia nurse's plan of care to prevent or manage PONV.  相似文献   
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