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61.
目的研究瓜萎燕白半夏汤对缺血再灌注损伤大鼠心肌细胞凋亡及Bcl-2 , Bax蛋白表达影响〔方法通过 结扎大鼠冠状动脉左前降支造成心肌缺血再灌注损伤模型,各组动物至实验时限心肌缺血30 min、再灌注90 min后, 取出心脏、采用TUNEL检测心肌细胞凋亡,免疫组化方法检测心肌Bcl-2 , Bax蛋白表达、结果与假手术组对照,模型 组细胞凋亡率及Bax表达水平均明显升高、Bcl-2表达水平降低,组间比较差异有统计学意义(P<0.01);瓜萎燕白半夏 能有效降低Bax表达、升高Bcl-2表达水平,抑制细胞凋亡的发生,与模型组比较,差异有统计学意义(P<0.01)、结论瓜 萎燕白半夏汤可能通过上调Bcl-2 ,卜调Bax蛋白表达而有效抑制心肌缺血再灌注损伤大鼠心肌细胞凋亡的发生  相似文献   
62.
Objective: To determine changes in hemodynamic and cardiac energetic parameters in dogs after induction of portal hypertension and gastric ischemia. These blood flow alterations are similar to changes seen in splanchnic blood flow in dogs with gastric dilatation volvulus syndrome (GDV). Design: Original experimental study. Setting: Veterinary teaching hospital. Animals: Seven purpose‐bred, intact male dogs. Interventions: Standard midline laparotomy and median sternotomy were performed under general anesthesia. Dogs were instrumented to obtain arterial blood pressure, aortic flow, cardiac chamber pressures, central venous pressure, portal flow, and portal pressure. Colored microsphere technology was used for the determination of myocardial blood flow. Measurements and samples were obtained at baseline, following induction of portal hypertension, and after induction of portal hypertension and gastric ischemia. Measurements and main results: Left ventricular myocardial blood flow was increased from 81.8±20.1 mL/100 g/min at baseline to 127.7±57.2 mL/100 g/min (P=0.02) after induction of portal hypertension and gastric ischemia. Myocardial oxygen consumption increased from 142.2±27.4 J/min/100 g at baseline to 219.1±33.4 J/min/100 g (P=0.003) after induction of portal hypertension and gastric ischemia, but cardiac external work remained unchanged (13.67±6.2 to 13.27±9.6 J/min; P=0.78; power=0.79). Cardiac efficiency decreased from 11.6±6.1% at baseline to 7.6±5.1% (P=0.017) after induction of portal hypertension and gastric ischemia. Conclusions: Transfer of energy within the myocardium was less efficient after induction of portal hypertension and ischemia of the stomach wall. On the basis of these results, alterations in cardiac function associated with GDV may result from deterioration of cardiac efficiency.  相似文献   
63.
Objective – To compare the determination of cardiac output (CO) via arterial pulse pressure waveform analysis (FloTrac/Vigileo) versus lithium dilution method. Design – Prospective study. Setting – University teaching hospital. Animals – Six adult dogs. Interventions – Dogs were instrumented for CO determinations using lithium dilution (LiDCO) and FloTrac/Vigileo methods. Direct blood pressure, heart rate, arterial blood gases, and end‐tidal isoflurane (ETIso) and CO2 concentrations were measured throughout the study while CO was manipulated with different depth of anesthesia and rapid administration of isotonic crystalloids at 60 mL/kg/h. Measurements and Main Results – Baseline CO measurements were obtained at 1.3% ETIso and were lowered by 3% ETIso. Measurements were obtained in duplicate or triplicate with LiDCO and averaged for comparison with corresponding values measured continuously with the FloTrac/Vigileo method. For 30 comparisons between methods, a mean bias of ?100 mL/kg/min and 95% limits of agreement between ?311 and +112 mL/kg/min (212 mL/kg/min) was determined. The mean (mL/kg/min) of the differences of LiDCO?Vigileo=62.0402+?0.8383 × Vigileo, and the correlation coefficient (r) between the 2 methods 0.70 for all CO determinations. The repeatability coefficients for the individual LiDCO and FloTrac/Vigileo methods were 187 and 400 mL/kg/min, respectively. Mean LiDCO and FloTrac/Vigileo values from all measurements were 145 ± 68 mL/kg/min (range, 64–354) and 244 ± 144 mL/kg/min (range, 89–624), respectively. The overall mean relative error was 48 ± 14%. Conclusion – The FloTrac/Vigileo overestimated CO values compared with LiDCO and the relative error was high, which makes this method unreliable for use in dogs.  相似文献   
64.
吴锋  段金旗 《勤云标准版测试》2017,37(11):1261-1264
目的 探讨针刺联合药物治疗心脏神经官能症(cardiac neurosis,CN)的临床疗效。方法 选取本院门诊就诊的90例CN患者,随机分为单纯针刺组、单纯药物组、针刺+药物组,每组各30例。单纯针刺组取百会、神庭、内关、神门、心俞、大陵常规针刺为主,单纯药物组给予规律口服西药酒石酸美托洛尔、谷维素片、氟哌噻吨美利曲辛片,针刺+药物组为上述针刺疗法结合西药治疗,共治疗8周。于治疗前、治疗4周和8周后观察3组的汉密顿抑郁量表(HAMD)评分和汉密顿焦虑量表(HAMA)评分,比较治疗后3组患者的临床疗效。结果 治疗4周、8周后,3组患者HAMD、HAMA评分均较治疗前有所降低(P<0.05,P<0.01);单纯针刺组和单纯药物组患者在治疗4周后和8周后的HAMD、HAMA评分均高于针刺+药物组,差异有统计学意义(P<0.05)。单纯针刺组和单纯药物组总有效率均低于针刺+药物组,差异比较有统计学意义(P<0.05,P<0.01)。结论 单纯针刺和西药治疗CN有一定的效果,两者合用后治疗效果得到较大的提高,可将药物治疗和针刺疗法有机的结合广泛应用于临床。  相似文献   
65.
Robert A.  Holmes  DVM  MS  Fred G.  Smith  DVM  PhD  Robert E.  Lewis  DVM  MS  Dennis M.  Kern  PhD 《Veterinary radiology & ultrasound》1985,26(3):98-101
Cardiac mensuration was done on thoracic radiographs of Beagles to determine the effects of rotation on the cardiac silhouette in dorsal recumbency. As the thorax became more rotated, surfaces of the heart not normally seen were projected, making interpretation of cardiac changes unreliable. A positioning standard based on the relationship of the dorsal spinous processes to the vertebral body was developed. If the tips of the dorsal spinous processes were within the bounds of the vertebral bodies, the radiographs were suitable for cardiac interpretation. If the tips of the dorsal spinous processes were outside the bounds of the vertebral bodies, there was enough rotation to make interpretation unreliable. A microcomputer, digitizer pad, and a BASIC language program were used to input, store, and calculate the various cardiac mensuration parameters.  相似文献   
66.
First-pass nuclear angiocardiography was performed on 13 normal horses and 5 horses with confirmed left-to-right ventricular septal defects. Two methods of analyzing the ensuing pulmonary time-activity histograms for shunt recirculation through the lungs were evaluated: (1) pulmonary-to-systemic blood flow ratio (QP:QS), based on gamma variate modeling of the lung histogram, and (2) a simple count-ratio method (C2:C1). Normal values were QP:QS=1.17±0.04 and C2:C1=0.40±0.07. Values for the five horses with left-to-right shunts were QP:QS=2.94±0.13 and C2:C1=0.76±0.11. Both parameters showed significant differences (unpaired t -test; p <0.005) between the two groups, although separation was better with QP:QS.  相似文献   
67.
Objective: To evaluate the efficacy and safety of biphasic (BP) defibrillation in toy breed dogs (<5 kg of body weight).
Design: Prospective, clinical experimental study.
Setting: Veterinary teaching hospital.
Animals: Five dogs (pilot study) and 10 dogs (comparison study of biphasic versus monophasic defibrillation).
Measurements and main results: The efficacy of defibrillation was compared by estimating E80 (80% probability of successful defibrillation) after biphasic (BP) and monophasic (MP) defibrillations. The E80 for BP defibrillation was 7.24±1.33 J (2.24±0.41 J/kg) and 10.24±1.34 J (3.18±0.12 J/kg) for MP defibrillation. BP waveform required 30% less shock energy for a successful defibrillation. In order to compare the safety of defibrillation, we evaluated changes in cardiac biomarkers, electrocardiogram, echocardiographical left ventricular index, and aortic pressure during and after BP and MP defibrillation. All dogs treated by either BP or MP defibrillation survived. Pulseless electrical activity occurred in 2 of 5 dogs during MP defibrillation. The levels of cardiac biomarkers were elevated and sustained for longer periods in the MP defibrillation group. Electrocardiographic changes (e.g., QT prolongation, the time to return to an isoelectric ST segment after shocks) were more severe and longer in the MP defibrillation group. In addition, overall left ventricular cardiac performance was severely depressed in the MP group compared with the BP group.
Conclusion: Our findings suggest that BP defibrillation is more effective and safer than MP defibrillation. We determined the acceptable shock energy to be 2–4 J/kg for toy breed dogs.  相似文献   
68.
Pulmonary valve stenosis (PS) is one of the most commonly diagnosed congenital heart defects in dogs. Currently, transthoracic echocardiography (TTE) is the standard modality used to evaluate PS. Image acquisition by TTE can be challenging in some brachycephalic breeds of dogs. The use of echocardiographic‐gated CT angiography (ECG‐gated CTA) in veterinary medicine is limited. This retrospective method comparison study investigated right and left ventricular outflow diameters by sedated ECG‐gated CTA and unsedated TTE in 14 brachycephalic dogs with PS and 12 brachycephalic dogs without PS. Measurements of ventricular outflow structures were made in early systole and end diastole for both modalities and then compared for significance between systolic and diastolic phases, as well as between the two modalities. Ratios of the pulmonary trunk diameter to the aorta at different locations (aortic valve, aortic annulus, and ascending aorta) and in different planes (transverse, sagittal) were compared between dogs with PS and without PS, as well as within dogs, by both TTE and ECG‐gated CTA. Transthoracic echocardiography and ECG‐gated CTA both detected significantly greater pulmonary trunk to aorta ratios in dogs with PS at all aortic locations (P < 0.05). Pulmonary valve to aortic valve ratios were significantly smaller in dogs with PS (P < 0.05). Pulmonary trunk to aorta and pulmonary valve to aorta ratios were achieved with good anatomic detail using ECG‐gated CTA. Ratios of the pulmonary trunk and pulmonary valve relative to the aorta may be useful to evaluate for PS using a modality that is underutilized for cardiac assessment.  相似文献   
69.
The purpose of this study was to assess radiographic heart size in anesthetized dogs, comparing radiographs made with the patient breathing spontaneously to radiographs obtained using positive pressure manual lung inflation. The hypothesis was that manual inflation would cause reduction in the cardiac size. With dogs in right recumbency a radiograph was made at peak spontaneous inspiration followed immediately a radiograph made with application of positive pressure manual inflation of the thorax. Cardiac size was assessed, both subjectively and objectively using the vertebral heart scale (VHS). Two hundred and six dogs were studied. Manual inflation resulted in a significantly greater degree of lung inflation assessed radiographically ( P <0.0001). The subjectively assessed heart size was significantly smaller in radiographs made with manual inflation, leading to different subjective categorization of heart size in 67 (32%) of dogs. The objectively measured VHS was also significantly smaller in the radiographs made using manual inflation by a mean of 0.24 of a vertebral length (95% CL of mean difference: −0.29, −0.19, P <0.0001). A statistically significant reduction in subjective heart size and in VHS occurred with manual inflation of the lungs, and these differences may be clinically significant. Thus, if serial radiographs are obtained to assess cardiac size, the radiographic technique used should be the same.  相似文献   
70.
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