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51.
心脏搭桥术对糖尿病人降糖治疗方案的影响   总被引:1,自引:0,他引:1  
目的 :通过观察 型糖尿病 (DM- )行心脏冠脉搭桥术 (CABG)术后血糖水平的升高到恢复至术前状态的过程 ,从而判断 CABG对 DM- 降糖治疗的影响。方法 :选择 36例 DM- 合并冠心病病人 ,均于体外循环 (CPB)下行心脏搭桥术 ,从术前监测血糖 ,直至术后第七天 ,于术中及术后根据血糖水平适当应用胰岛素 ,观察其对降糖治疗效果及血糖趋于稳定的过程 ,从而判断 CABG对 DM- 血糖的影响。结果 :术中及术后 1~ 3d血糖会较术前明显升高 ,需加用胰岛素助降糖 ,术后 3d血糖渐降 ,第六天趋于稳定 ,第七天恢复至接近术前水平。结论 :DM- ,病人行 CABG术 ,只要围术期有效控制血糖 ,术后血糖基本会逐渐恢复至术前状态 ,对其今后的降糖治疗不会造成严重影响  相似文献   
52.
We present a physiologically stable porcine model designed for sequential assessments of pharmacological effects on mean hemispheric cerebral blood flow (CBF) and cerebral metabolic rate for oxygen (CMRO2) at sustained normocapnia. The dynamic influence of continuously administered fentanyl (0.040 mg.kg-1.h-1 i.v.), nitrous oxide (70%) and pancuronium (0.30 mg.kg-1.h-1 i.v.) on these variables was studied in eight normoventilated pigs. CBF was reliably assessable at 10-min intervals by clearance of intra-arterially injected 133Xe, monitored by an extracranial scintillation detector. CMRO2 was calculated from CBF and the simultaneously measured cerebral arteriovenous difference in blood oxygen content. The intracerebral distribution of a contrast medium injected into the external and internal carotid arteries was studied by angiography, and the cerebral venous outflow was investigated by measurements of the distribution of an intra-arterially administered non-diffusible tracer, [99mTc]pertechnetate, to the internal and external jugular veins. After a 3-h equilibration period, CBF and CMRO2 were determined on six occasions over a study period lasting 1 h 40 min. The mean ranges of these variables were 56-60 and 1.9-2.0 ml.100 g-1.min-1, respectively. We conclude that the model enables repeated assessments of CBF and CMRO2 under stable physiological background conditions and thus valid cerebral pharmacodynamic investigations of drugs given for anaesthesia.  相似文献   
53.
目的 探讨主动吸入药物烟对大鼠NO的影响。方法 制备大鼠主动吸烟模型 ,采用硝酸还原酶法测定各组大鼠血清、肺、心肌及脑组织的NO含量。结果 非药物烟组大鼠血清、肺、心肌及脑组织中NO含量明显低于非给烟对照组 ,药物烟高、中剂量组NO含量明显高于非药物烟组 ,接近非给烟对照组。结论 吸烟对大鼠血液、肺、心肌及脑组织有不同程度的损伤作用 ,使NO含量降低 ;药物烟具有一定的保护和防止NO含量降低的作用。  相似文献   
54.
PURPOSE: To examine the application of statistical parametric mapping (SPM) to analyze ictal single-photon emission computed tomography (SPECT) scans in surgical candidates with extratemporal lobe epilepsy. METHODS: The authors selected patients who underwent successful ictal SPECT acquisition in the process of surgical treatment of intractable partial epilepsy. Thirteen patients were identified who met inclusion criteria for confident seizure localization from either intracranial electroencephalogram recordings or epilepsy surgery outcome. In these cases, ictal scans were registered to an in-house-developed normal SPECT atlas composed of 14 spatially normalized brains of normal subjects. SPM96 was used to test on a voxel-by-voxel basis for statistically significant increases in blood flow associated with each patient's ictal scan. The results were then mapped back onto the patient's magnetic resonance image (MRI) for final interpretation. Statistical parametric mapping (SPM) analysis of ictal SPECT scans was compared to both conventional visual interpretation and the analysis of subtraction ictal SPECT co-registered to MRI (SISCOM). RESULTS: Ten of 13 patient scans showed localizing focal ictal increases in regional cerebral blood flow, all of which were concordant with ultimate epilepsy localization. Of the 3 cases not localized with SPM, 1 was localized by conventional visual interpretation and another, not localized by visual interpretation, was correctly localized with SISCOM. Two cases not localized by SISCOM were localized by both visual and SPM analysis. CONCLUSIONS: This work provides supportive evidence for proof of principle that SPM can be used to provide objective, accurate analysis of ictal SPECT scans in patients with extratemporal lobe epilepsy.  相似文献   
55.
静脉血气分析及其临床应用进展   总被引:2,自引:0,他引:2  
张德平 《医学研究生学报》2004,17(8):741-743,748
动脉血气分析是严重心肺疾病和许多代谢性疾病的重要检测手段,在血流动力学稳定状态下,动、静脉血气的CO2气体含量和酸碱参数非常接近,但在循环功能衰竭等情况下,动、静脉血气出现分离现象,此时可能需同时作静脉血气。静脉血气分析对危重患者特别是循环衰竭的患者可以提供组织氧合和酸碱状态更切实的评价,并可能对有效复苏提供更好的指导。  相似文献   
56.
BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS) affects the excitability of the motor cortex and is thought to influence activity in other brain areas as well. We combined the administration of varying intensities of 1-Hz rTMS of the motor cortex with simultaneous positron emission tomography (PET) to delineate local and distant effects on brain activity. METHODS: Ten healthy subjects received 1-Hz rTMS to the optimal position over motor cortex (M1) for producing a twitch in the right hand at 80, 90, 100, 110, and 120% of the twitch threshold, while regional cerebral blood flow (rCBF) was measured using H(2)(15)O and PET. Repetitive transcranial magnetic stimulation (rTMS) was delivered in 75-pulse trains at each intensity every 10 min through a figure-eight coil. The regional relationship of stimulation intensity to normalized rCBF was assessed statistically. RESULTS: Intensity-dependent rCBF increases were produced under the M1 stimulation site in ipsilateral primary auditory cortex, contralateral cerebellum, and bilateral putamen, insula, and red nucleus. Intensity-dependent reductions in rCBF occurred in contralateral frontal and parietal cortices and bilateral anterior cingulate gyrus and occipital cortex. CONCLUSIONS: This study demonstrates that 1-Hz rTMS delivered to the primary motor cortex (M1) produces intensity-dependent increases in brain activity locally and has associated effects in distant sites with known connections to M1.  相似文献   
57.
本文观察了52侧(男46,女6)成人尸体臀上动、静脉深上支进入髂嵴情况.臀上动、静脉深上支分为前、中、后支;本文测量了臀上动、静脉深上支的外径及各分支进入髂嵴的距离.臀上动、静脉深上支的分支在髂嵴前部及中部分布较多,前支的分支为3~8支,其中以4~6支者为多见,占78.8±5.5%;中支的分支1~4支,其中以2~3者为多见,占73.1±6.1%.因此,臀上动脉深上支作为游离髂骨移植术取髂嵴的前部和中部较宜.  相似文献   
58.
The cardiovascular effects of mesulergine were studied in anesthetized dogs. Intravenous (IV) administration (0.3 mg/kg) significantly decreased blood pressure in neurogenic hypertensive dogs without any change in heart rate. This effect was completely antagonized by IV administration of domperidone (0.5 mg/kg). Intracisternal administration of mesulergine (0.03, 0.3 and 3 mg/kg) did not produce any change in blood pressure. However, with the highest dose we observed a significant rise in heart rate during the first 2 min (which was probably nonspecific). These results suggest that mesulergine lowers blood pressure in sinoaortic-denervated dogs by means of a peripheral mechanism probably involving DA2 receptors. The findings confirm the potential interest of dopamine-receptor agonists as future antihypertensive agents.  相似文献   
59.
以23例肾功能不全与20例肾功正常患者的唾液尿素氮、钠、钾、舌面pH值和血液的相应生化检查作对照。结果唾液尿素氮、钾与血尿素氮、钾成正相关性。证实了中医“津血同源”“肾为唾”的理论。  相似文献   
60.
A role of insular cortex in cardiovascular function   总被引:5,自引:0,他引:5  
We sought to determine whether the insular cortex contributes to the regulation of arterial blood pressure (AP). Responses to electrical and chemical stimulation of the cortex were studied in the anesthetized, paralyzed, and artificially ventilated Sprague-Dawley rat. The insular cortex was initially defined, anatomically, by the distributions of retrogradely labeled perikarya following injections of wheat germ agglutinin-horseradish peroxidase (WGA-HRP) into the nucleus tractus solitarii (NTS). Injections of WGA-HRP into the insular cortex anterogradely labeled terminals in cardiopulmonary and other divisions of the NTS and confirmed projections revealed by retrograde tracing experiments. Electrical stimulation of the insular cortex elicited elevations of AP (less than or equal to 50 mm Hg) and cardioacceleration (less than or equal to 40 bpm). The locations of the most active pressor sites corresponded closely to the locations of retrogradely labeled cells in layer V of granular and posterior agranular areas of the insular cortex (areas 14 and 13) and the extreme capsule. Maximal pressor responses were obtained at a stimulus intensity of three to five times threshold current of 20-30 microA. Responses elicited mostly with higher-threshold currents were also mapped in areas 2a and 5lb and the claustrum and within the corpus callosum. Unilateral injections into the insular pressor area of the excitatory amino acid monosodium glutamate (L-Glu; 0.05 nmol to 10 nmol) or the rigid structural analogue of L-Glu, kainic acid (KA) (0.4 nmol) (which specifically excite perikarya), caused topographically specific elevations in AP and tachycardia. During the course of the anatomical transport studies, new findings were obtained on the organization and characteristics of the cortical innervation of the NTS and the nucleus reticularis parvocellularis. Topographic relationships between the cortex and the NTS were organized in a more complex manner than previously thought. Cells projecting to caudal cardiopulmonary segments of the NTS were fewer and generally located ventrally and caudally and in a more restricted area than cells projecting rostrally or to the parvicellular reticular formation. Anterograde transport data revealed new presumptive terminal fields in dorsolateral, ventral, periventricular, and commissural regions of the NTS, including an area overlapping the terminal field of the aortic baroreceptor nerve. We conclude that neurons within an area of the insular cortex projecting to multiple brainstem autonomic nuclei, including a region of the NTS innervated by baroreceptor afferents, increase arterial blood pressure and heart rate.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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