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排序方式: 共有260条查询结果,搜索用时 15 毫秒
61.
F. GRUND H. T. SOMMERSCHILD A. WINECOFF M. R. UJHELYI T. T
NNESSEN K. A. KIRKEB
EN D. L. RUTLEN A. ILEBEKK 《Acta physiologica (Oxford, England)》1997,161(3):303-309
The importance of nitric oxide in regulating basal arterial blood flow has been examined in several different vascular beds by intra-arterial infusion of inhibitors of nitric oxide synthesis, but not in the arterial vascular bed of the liver. In the present study, NG-nitro-L -arginine (L -NNA), in a dose of 0.5 and 1.0 μmol mL?1 of hepatic arterial blood flow, was infused for 5 min into the hepatic artery in seven pigs anaesthetized with pentobarbital sodium. The haemodynamic effects observed by the first infusion were not further enhanced by the second infusion. Hepatic arterial resistance increased by 143 ± 38% and hepatic arterial blood flow declined by 38 ± 10%. A systemic effect due to `spillover' was observed, as evidenced by an increase in mean aortic blood pressure of 24 ± 4 mmHg. However, no significant increase in arterial mesenteric resistance was observed and total liver blood flow remained unchanged. Hepatic arterial vasodilation in response to occlusion of the portal vein, the arterial buffer response, remained intact after inhibition of nitric oxide synthesis. Liver lobe thickness, measured by an ultrasonic technique,was not found to change with inhibition of arterial nitric oxide synthesis, excluding a significant direct effect of arterial nitric oxide on liver capacitance. In conclusion, nitric oxide is an important regulator of hepatic arterial resistance, but does not mediate the hepatic arterial buffer response and was not found to play any significant role in total hepatic capacitance regulation. 相似文献
62.
Fikriye Yasemin
ZATK Orhan
ZATK Yasemin TEKEN Semra YTASLAN Neziha Senem ARI 《Turkish Journal of Medical Sciences》2021,51(3):1530
Backround/aimCyclophosphamide (CP) is a drug used for treatment of many malignant diseases. However, it can cause serious side effects such as hemorrhagic cystitis and male infertility. Hydrogen sulfide (H2S) is a gaseous mediator and is suggested to have antioxidant, antiinflammatory, and antiapoptotic effects. In this study, dose-dependent effects of H2S donor sodium hydrosulfide (NaHS) on cyclophosphamide-induced hemorrhagic cystitis and testicular dysfunction were investigated in rats.Material and methodsRats were divided into 5 groups (n = 8): control, CP, NaHS25 μmol/kg, NaHS50 μmol/kg, and NaHS100 μmol/ kg. After treatment for 7 days intraperitoneally (ip), a single ip dose of CP 200 mg/kg was given on the 8th day. Then, treatment was continued for 7 days. In bladder and testicular tissues, IL 6, IL 10, cGMP, NO, H2S, FSH, LH, and testosterone levels were measured by ELISA. Histopathological examination with H&E staining, as well as immunohistochemical staining for acrolein in bladder and caspase-3 and APAF-1 in testis were performed.ResultsNaHS prevented the increased IL 6 and IL 10 values induced by CP as well as prevented the decrease in cGMP values associated with CP. There was no significant change in FSH values, but the LH value, which increased with CP, decreased with 25, 50, and 100 μmol/kg NaHS. In contrast, testosterone decreased in the CP group and increased in the treatment groups. NaHS was effective in many biochemical and histopathological parameters at 25 and 50 μmol/kg doses, and this effect decreased at 100 μmol/kg dose.ConclusionH2S has a protective and therapeutic effect on hemorrhagic cystitis and testicular dysfunction induced by cyclophosphamide. It can be suggested that H2S is a promising molecule in facilitating cancer treatment. 相似文献
63.
Background
The role of nurses in the health care delivery system cannot be overemphasized. Nurses are needed at all levels of healthcare and the profession requires a lot of dedication, time and energy with regards to patient management and service delivery. This time investment and dedication to duty is likely to lead to burnout and psychological distress among the nurses.Objective
This study assesses the prevalence of burnout and psychological distress among nurses working in Nigerian tertiary health institution.Method
The Maslach Burnout Inventory (MBI) and the General Health Questionnaire (GHQ-12) were used to assess 210 nurses working in this health institution for symptoms of burnout and psychological distress.Results
High levels of burnout were identified in 42.9% of the respondents in the area of emotional exhaustion, 47.6% in the area of depersonalization and 53.8% in the area of reduced personal accomplishment, while 44.1% scored positive in the GHQ-12 indicating presence of psychological distress.Conclusion
Prevalence of burnout and psychological distress is high among nurses. 相似文献64.
65.
目的 通过分析强直性脊柱炎后凸畸形矫形临床路径实施的变异程度,研究该临床路径可能存在的不足并提出适当的改进方案。方法 收集自2012年1月至2013年12月的350例符合强直性脊柱炎后凸畸形矫形临床路径适应证的患者的资料,并根据变异的标准及类型进行统计分析。结果 350例病例中有290例发生变异,包括了16种变异情况,类型以负性变异、患者病情变化、不可控变异为主。结论 强直性脊柱炎后凸畸形矫形临床路径需要完善运行流程、制定详细的纳入和排除标准、同时加强社区医院及康复医院的相应诊疗过渡,从而更好地开展强直性脊柱炎后凸畸形矫形临床路径,最终提高患者医护质量、减少住院天数、降低住院费用。 相似文献
66.
Heringer-Walther S Batista EN Walther T Khosla MC Santos RA Campagnole-Santos MJ 《Hypertension》2001,37(5):1309-1314
ACE inhibitors are extensively used in the treatment of hypertension mainly because of their efficiency in reducing blood pressure levels and decreasing vascular and cardiac hypertrophy. In addition, ACE inhibitors improve baroreceptor reflex control. Chronic inhibition of ACE produces (in addition to decreased angiotensin II levels) a severe increase in angiotensin-(1-7) [Ang-(1-7)] levels in several species. We have previously shown that Ang-(1-7) produces a facilitation of the baroreflex control of heart rate. In this study, we evaluated the participation of endogenous Ang-(1-7) in the improvement of baroreflex sensitivity in spontaneously hypertensive rats after central infusion of ramiprilat, an ACE inhibitor. Reflex changes in heart rate were elicited, in conscious rats, by bolus injections of phenylephrine (baroreflex bradycardia) before and after intracerebroventricular infusion of (1) saline (8 microL/h), 4 hours (n=5); (2) ramiprilat (14 microg/h), 4 hours (n=6); (3) ramiprilat for 2 hours, followed by ramiprilat combined with A-779 (4 microg/h), a selective Ang-(1-7) antagonist, for an additional 2 hours (n=6); and (4) A-779 for 2 hours, followed by A-779 combined with ramiprilat for an additional 2 hours (n=5). Intracerebroventricular infusion of ramiprilat produced an important increase ( approximately 40%) in baroreflex sensitivity (evaluated as the ratio between changes in heart rate and changes in mean arterial pressure) that was completely reversed by A-779. Furthermore, intracerebroventricular infusion of A-779 prevented the improvement of the baroreflex sensitivity produced by ramiprilat. Intracerebroventricular infusion of saline or A-779 alone did not significantly alter the baroreflex sensitivity. These results suggest that endogenous Ang-(1-7) is involved in the improvement of baroreflex sensitivity observed in spontaneously hypertensive rats during central ACE inhibition. 相似文献
67.
T_3对人神经干细胞分化过程中甲状腺激素受体表达的影响 总被引:1,自引:0,他引:1
目的 探讨三碘甲状腺原氨酸 (T3)在神经干细胞 (NSC)分化中的作用以及甲状腺激素受体(TR)mRNA在NSC分化过程中的表达变化。方法 在体外成功诱导扩增NSC ,用T3 对NSC进行诱导分化 ,半定量RT PCR法检测NSC在分化前后TRsmRNA的表达变化 ,免疫细胞化学方法鉴定分化后的细胞类型。结果 T3 可诱导NSC分化为神经元、少突和星形胶质细胞 ,其中髓鞘碱性蛋白 (MBP)阳性细胞约占 80 %。当NSC分化时存在不同的TRsmRNA的时间顺序表达。结论 T3 能诱导NSC向胶质细胞分化 ,是少突胶质细胞分化的重要调控因子 ,并通过TRs的时间顺序表达来发挥其重要生理作用 相似文献
68.
目的:研究辛伐他汀对冠心病患者血管内皮细胞功能障碍的干预作用。方法:90例冠心病患者按LDL-C水平分为三组:辛伐他汀20mg组(37例,LDL-C≥2.5mmol/L),辛伐他汀10mg组(35例,2.5mmol/L〉LDL-C≥1.8mmol/L),常规治疗组(18例,LDL-C〈1.8mmol/L,未服辛伐他汀),疗程均为8周。应用彩色多普勒超声诊断仪测量受试者肱动脉血流介导的舒张功能(FMD)。应用硝酸还原酶法检测受试者一氧化氮(NO)的含量。常规检测血清TC、TG、LDL-C及HDL-C的浓度。结果:8周后,与治疗前比较,辛伐他汀20mg,10mg组TC、TG和LDL-C浓度明显下降(P均〈0.05),而HDL-C明显升高(P均〈0.05);辛伐他汀20mg组与10mg组间各指标差异无显著性(P〉0.05);与常规治疗组比较,辛伐他汀20mg、10 mg组FMD[(6.01±0.49)%比(9.01±0.39)%比(9.01±0.47)%]明显改善(P均〈0.01)、血清NO含量[(38.97±8.89)μmol/L比(47.67±10.89)μmol/L比(45.61±9.09)μmol/L]明显升高(P均〈0.05),辛伐他汀20mg、10 mg组两组间NO和FMD亦无显著差异(P〉0.05)。结论:辛伐他汀可增加冠心病患者一氧化氮含量,改善血管内皮细胞功能,其作用机制与降低血清总胆固醇、甘油三酯和低密度脂蛋白可能有一定关系,但该作用无明显的量效关系,可能独立于降脂作用之外。 相似文献
69.
SVEND-AAGE JOHNSEN AGNETHA OLOFSSON KRISTER GREN LARS B. OLDING 《American journal of reproductive immunology (New York, N.Y. : 1989)》1983,4(1):45-49
ABSTRACT: We have tested peripheral mononuclear leukocytes (PML) from the cord blood of newborns, from sera of their mothers, and from sera of nonrelated nonpregnant adult women for sensitivity to suppressive exogenous prostaglandin E2 (PGE2). Endogenous PG production was simultaneously inhibited by indomethacin 2.8 μM. The phytohemagglutinin-stimulated (PHA-stimulated) uptake of tritiated thymidine (3H-TdR) by PML from the mothers and the nonpregnant women was suppressed by the exogenous PGE2 at a concentration of 1.4 × 10?8 M, 100 times less than the one required to suppress the PML from newborns (1.4 × 10?6 M). In addition, 1.4 × 10?7 M or less of PGE2 reversed the suppression of neonatal PML to stimulation. The maternal PML were reversed into stimulation at 1.4 × 10?9 of exogenous PGE2. The amount of endogenous PGE2 synthesized by 1 × 106 fresh, nonstimulated neonatal PML according to gas chromatography-mass spectrometry assay was 5 ng (1.4 × 10?8 M). The synthesis increased to 27 ng/106 cells after 18 hours' incubation. These concentrations are similar to the ones of exogenous PGE2 at which neonatal PML were slightly stimulated but the maternal cells were still suppressed. Preincubation for 18 h at 37°C decreased the PGE2-induced suppression of the adult PML but did not change the response of the neonatal PML. 相似文献
70.
Effect of phagocytosis on the reduced soluble sulfhydryl content of human granulocytes 总被引:3,自引:0,他引:3
The role of reduced glutathione in relation to hexose monophosphate shunt activity and peroxide detoxification has been well established in human erythrocytes. Less is known about the content of reduced glutathione in phagocytic leukocytes and the changes that occur during functional activity. We have measured the reduced sulfhydryl content of normal resting human granulocytes and of cells isolated from a patient with chronic granulomatous disease. Normal cells and those from the patient with chronic granulomatous disease contained similar concentrations of reduced sulfhydryls. Stimulation of a phagocytic response by incubation with opsonized zymosan particles resulted in prompt and nearly complete depletion of intracellular glutathione from normal granulocytes. This fall in reduced glutathione concentration was dependent on the phagocytic load. Exposure of chronic granulomatous disease granulocytes to a similar phagocytic load resulted in a slower and less complete fall in reduced glutathione. In normal cells, those from the chronic granulomatous disease patient, and those from an obligate carrier of the disease, the decrement in reduced glutathione during phagocytosis was correlated with oxidation of 14C-1-glucose and 14C-formate, nitroblue tetrazolium reduction, and the chemiluminescence phenomenon. 相似文献