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排序方式: 共有462条查询结果,搜索用时 15 毫秒
51.
SANMIGUEL CP HAGIIKE M MINTCHEV MP DELA CRUZ R PHILLIPS E CUNNEEN SA CONKLIN JL SOFFER EE 《Neurogastroenterology and motility》2006,18(6):484-485
Background: Electrical stimulation (ES) of the stomach has been shown to modulate LESP. Electrical stimulation, using neural high frequency stimulation (NGES) can induce contractions of the smooth muscle of the gut. The purpose of this study was to determine if electrical stimulation of the LES can affect LESP. Methods: Four female hound dogs, weight: 20–25 kg, underwent an esophagostomy that allowed the introduction of a sleeve manometry catheter into the esophagus. They were also implanted with a pair of electrodes along the longitudinal axis of the LES. After 3 weeks of recovery, they underwent esophageal manometry recording during control and ES, performed randomly on separate days, using 4 different stimulations: 1‐Low frequency: freq: 6 cycles/min, pulse: 350 milisec, amp: 5 mAmp; 2 High‐frequency: freq: 50 Hz, pulse: 1 milisec, amp: 5 mAmp; 3‐ NGES: freq: 50 Hz, pulse:20 milisec, amp:10 volts; 4‐ High‐frequency, circular: freq: 20 Hz, pulse:1 milisec, amp:5 mAmp. All recordings were performed 1 hour after consumption of 3 ounces of canned dog food, to prevent fluctuations in LESP and under mild sedation (acepromazine 0.5 mg kg1). Tests consisted, during ES days, of 3 periods of 20 minutes each: control , stimulation and post stimulation. The effect of NGES was also tested under anesthesia and following administration of L‐NAME 50 mg kg1 IV. and also atropine 0.05 mg kg1 IV. Analysis: area under the curve (AUC) and pressure were compared among the 3 periods. Data shown as mean ± SD, ANOVA and t‐test, p < 0.05. Results: Sustained increase in LESP was observed during low frequency stimulation, 32.1 ± 12.8 vs. 42.4 ± 18.0 vs. 50.1 ± 23.6, control vs. stimulation vs. post stimulation respectively, p = 0.013. AUC also significantly increased during and after stimulation, 39,320.3 ± 15,722 vs. 51,294 ± 21,826 vs. 59,823.6 ± 28,198.4 mmHgxsec, control vs. stimulation vs. post stimulation respectively, p = 0.01. There was no significant change with other types of ES. NGES induced an initial rise in LESP followed within few seconds by relaxation with slow resumption of pressure over a 1 minute period. L‐NAME increased LESP and augmented the initial rise in LESP following NGES but markedly diminished or abolished the relaxation phase. Atropine lowered LESP and abolished the initial rise in LESP induced by NGES. Conclusions: Low frequency ES of the LES increases LESP in conscious dogs. NGES has dual effect on LESP: an initial stimulation, cholinergically mediated, followed by relaxation mediated by nitric oxide. 相似文献
52.
CGH Dahlöf L Falk M Risenfors CP Lewis 《Cephalalgia : an international journal of headache》1998,18(8):546-551
We investigate whether symptoms of pressure, tightness, and/or pain in the chest, neck, and/or throat after administration of the 5HT1B/1D agonist avitriptan were associated with objective impairment of the myocardial function on 12-lead electrocardiogram (ECG), continuous ECG (Holter) monitoring, and echocardiography. Migraine sufferers who in two-thirds of alt attacks treated with sumatriptan had experienced chest/throat/neck symptoms were chosen for study. Baseline measures included vital signs, a 12-lead ECG and an echocardiogram. Patients ( n =51) who had no clinically significant abnormality at baseline received a high dose (150 mg) of avitriptan orally outside of a migraine attack. If pressure, tightness, and/or pain in the chest, neck, and/or throat occurred, an ECG was obtained, and a repeat echocardiogram was done while the symptoms were present in order to monitor for impairment of myocardial function. If symptoms of these types did not occur within 60 min after administration of the study drug, a second echocardiogram was obtained. Forty-five patients (88%) reported at least one adverse event and 23 (45%) experienced pressure, tightness, and/or pain in the chest, neck, and/or throat after administration of avitriptan. No clinically significant myocardial abnormalities were observed in any patient, even in those who had experienced the targeted symptoms. No other serious adverse event occurred. We concluded that the typical 5HT1B/1D agonist-induced chest/throat/neck symptoms are most unlikely to be of cardiovascular origin. 相似文献
53.
Daniel Kotz Geertjan Wesseling Marcus JH Huibers Onno CP van Schayck 《BMC public health》2007,7(1):332
Background
The use of spirometry for early detection of chronic obstructive pulmonary disease (COPD) is still an issue of debate, particularly because of a lack of convincing evidence that spirometry has an added positive effect on smoking cessation. We hypothesise that early detection of COPD and confrontation with spirometry for smoking cessation may be effective when applying an approach we have termed "confrontational counselling"; a patient-centred approach which involves specific communication skills and elements of cognitive therapy. An important aspect is to confront the smoker with his/her airflow limitation during the counselling sessions. The primary objective of this study is to test the efficacy of confrontational counselling in comparison to regular health education and promotion for smoking cessation delivered by specialized respiratory nurses in current smokers with previously undiagnosed mild to moderate airflow limitation. 相似文献54.
女性护理专业学生心理健康相关因素分析 总被引:1,自引:0,他引:1
目的:分析护理专业学生心理健康的影响因素。方法:于2005-12-01/15按整群抽样法抽取西安市高校在读的护理专业学生515名作为被调查对象。症状自评量表总分≥187为高分组,总分≤116为低分组。高分组与低分组配比的条件是均为女性,年龄相差不超过3岁。采用症状自评量表、简易应对方式问卷、自尊量表、护理专业学生相关状况调查表进行问卷调查。对调查变量进行单因素和多因素Logistic回归分析。结果:共发放问卷515份,其中2名学生生病未填写调查表,应答率为99.6%。调查中有效问卷共507份,有效率为98.8%。症状自评量表总分高分组与低分组学生各100名。①护理专业学生心理健康相关个人因素(计量变量)单因素分析结果:高分组积极应对、自尊水平得分明显低于低分组(20.47±5.02,22.15±6.02;25.91±3.60,30.96±3.25),差异有显著性意义(P<0.05,P<0.01)。高分组消极应对得分明显高于低分组(12.57±4.08,8.00±4.12),差异有显著性意义(P<0.01)。②护理专业学生心理健康相关个人因素(二分类变量)单因素分析结果表明,高分组与低分组比较差异有显著性的因素有独生子女、远离家人、孤独、学习压力大、担心拿不到学位、自我实现需要的满足、经常被人误会、受人歧视、失恋、有知心朋友、无处倾诉苦恼、睡眠型态紊乱、近1年来本人健康改变、适应新环境、经常参加体育活动、担心毕业分配、现有最担心的事情。③多因素分析显示,学习压力大(OR=10.017)、近1年来本人健康改变(OR=4.384)为护理专业学生心理健康状况不良的独立危险因素,而自我实现需要的满足(OR=0.037)、高水平自尊(OR=0.357)是保护因素。结论:护理专业学生心理健康状况与教育、成长、社会环境等多方面因素相关,其心理健康干预需考虑学生的个人因素有针对性地进行。 相似文献
55.
56.
Betty K Samulitis Kelvin W Pond Erika Pond Anne E Cress Hitendra Patel Lee Wisner Charmi Patel Robert T Dorr Terry H Landowski 《Cancer biology & therapy》2015,16(1):43-51
Gemcitabine based treatment is currently a standard first line treatment for patients with advanced pancreatic cancer, however overall survival remains poor, and few options are available for patients that fail gemcitabine based therapy. To identify potential molecular targets in gemcitabine refractory pancreatic cancer, we developed a series of gemcitabine resistant (GR) cell lines. Initial drug exposure selected for an early resistant phenotype that was independent of drug metabolic pathways. Prolonged drug selection pressure after 16 weeks, led to an induction of cytidine deaminase (CDA) and enhanced drug detoxification. Cross resistance profiles demonstrate approximately 100-fold cross resistance to the pyrimidine nucleoside cytarabine, but no resistance to the same in class agents, azacytidine and decitabine. GR cell lines demonstrated a dose dependent collateral hypersensitivity to class I and II histone deacetylase (HDAC) inhibitors and decreased expression of 3 different global heterochromatin marks, as detected by H4K20me3, H3K9me3 and H3K27me3. Cell morphology of the drug resistant cell lines demonstrated a fibroblastic type appearance with loss of cell-cell junctions and an altered microarray expression pattern, using Gene Ontology (GO) annotation, consistent with progression to an invasive phenotype. Of particular note, the gemcitabine resistant cell lines displayed up to a 15 fold increase in invasive potential that directly correlates with the level of gemcitabine resistance. These findings suggest a mechanistic relationship between chemoresistance and metastatic potential in pancreatic carcinoma and provide evidence for molecular pathways that may be exploited to develop therapeutic strategies for refractory pancreatic cancer. 相似文献
57.
58.
James?C?Barton Howard?W?Wiener Ronald?T?ActonEmail author Rodney?CP?Go 《BMC blood disorders》2005,5(1):5
Background
It has been reported that some persons with hemochromatosis have low total blood lymphocyte counts, but the reason for this is unknown. 相似文献59.
Specificity of autoantibodies in autoimmune thrombocytopenia 总被引:12,自引:5,他引:12
In 42 patients with autoimmune thrombocytopenia (AITP) and a positive direct platelet suspension immunofluorescence test (PSIFT), the antigenic specificity of the autoantibodies was studied. Because the autoantibodies were often not detectable in the serum and additional HLA antibodies may disturb the reaction pattern with the platelet panel, we used eluates prepared from the patients' platelets for this study. Thirty-five patients had antibodies equally reactive with normal platelets, irrespective of their antigenic make-up, but not with the platelets from two Glanzmann's disease patients. Absorption and elution experiments in two patients showed that his was probably not due to the presence of a combination of anti-Zwa and anti-Zwb antibodies. Thus, the majority of autoantibodies against platelets seems to be directed against antigenic determinants not present on Glanzmann's disease platelets, but perhaps located on the platelet-membrane glycoproteins IIb and/or IIIa. In ten patients, antibodies of no, or still unknown, specificity were detected. Three of these had additional antibodies not reactive with the platelets of the two Glanzmann patients. 相似文献
60.
C Pothoulakis U Galili I Castagliuolo CP Kelly S Nikulasson PK Dudeja TA Brasitus JT LaMont 《Gastroenterology》1996,110(6):1704-1712
BACKGROUND & AIMS: Nearly all human sera contain an immunoglobulin G antibody (antigalactose) that binds the trisaccharide Gal alpha 1-3Gal beta 1-4GlcNAc expressed on cells from most mammals but not humans. Because the Clostridium difficile toxin A receptor in rodents contains this trisaccharide, the aim of this study was to examine whether antigalactose could mimic the enterotoxic effects of toxin A and bind to receptors containing this trisaccharide. METHODS: Fluid secretion, [3H]-mannitol permeability, and release of rat mast cell protease II and prostaglandin E2 were measured after luminal exposure of rat colon to either purified human anti-galactose, control immunoglobulin G, toxin A, or buffer. RESULTS: Toxin A (5 micrograms) and antigalactose (250 micrograms) but not control immunoglobulin (250 micrograms) stimulated colonic fluid secretion and caused increased mannitol permeability and rat mast cell protease II release. Antigalactose and toxin A and, to a lesser degree, control immunoglobulin G also stimulated release of prostaglandin E2, but only toxin A produced acute inflammation of rat colonic mucosa. Antigalactose and toxin A bound specifically to a single class of colonic brush border receptors with dissociation constants of 10(-6) mol/L and 5.4 x 10(-8) mol/L, respectively. CONCLUSIONS: Fluid secretion, increased permeability, and mast cell activation occur in rat colon when toxin A or human antigalactose immunoglobulin G bind to receptors bearing the trisaccharide Gal alpha 1-3Gal beta 1-4GlcNAc. (Gastroenterology 1996 Jun;110(6):1704-12) 相似文献