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11.
The purpose of this work was to investigate the use of an intravascular contrast agent to determine perfusion kinetics in skeletal muscle. A two-compartment kinetic model was used to represent the flux of contrast agent between the intravascular space and extravascular extracellular space (EES). The relationship between the image signal-to-noise ratio (SNR) and errors in estimating permeability surface area product (Ktrans), interstitial volume (ve), and plasma volume (vp) for linear and nonlinear curve-fitting methods was estimated from Monte Carlo simulations. Similar results were obtained for both methods. For an image SNR of 60, the estimated errors in these parameters were 10%, 22%, and 17%, respectively. In vivo experiments were conducted in rabbits to examine physiological differences between these parameters in the soleus (SOL) and tibialis anterior (TA) muscles in the hind limb. Values for Ktrans were significantly higher in the SOL (3.2+/-0.9 vs. 2.0+/-0.5x10(-3) min-1), as were values for vp (3.4+/-0.8 vs. 2.1+/-0.7%). Differences in ve for the two muscles (8.7+/-2.2 vs. 8.5+/-1.6%) were not found to be significant. These results demonstrate that relevant physiological metrics can be calculated in skeletal muscle using MRI with an intravascular contrast agent.  相似文献   
12.
Intraoperative and postoperative free flap monitoring by means of oxygen tension measurement was carried out in 11 patients. We used an invasive flexible microcatheter that allowed for measurement of oxygen tension in all types of free flaps. Two cases of the measured flaps were buried free flaps which do not allow monitoring by clinical assessment. All flaps monitored in this study survived. One case of displacement of the microcatheter occurred. In one patient, the tissue pO2 monitor successfully detected early vascular thrombosis with subsequent reoperation and salvage of the free flap.  相似文献   
13.
慢性肺心病哮喘持续状态218例临床分析   总被引:1,自引:0,他引:1  
朱盈援 《重庆医学》2006,35(18):1668-1670
目的探索治疗慢性肺心病哮喘持续状态的方法。方法回顾性分析1983年10月~2005年3月收治的218例慢性肺心病哮喘持续状态患者的临床资料。结果哮喘持续状态在48h以内被控制的62例(28.4%);在72h以内控制的56例(25.7%);在120h以内控制的25例(11.5%);在168h以内控制的34例(15.6%);痊愈出院177例(81.2%);死亡41例(18.8%)。结论(1)治疗慢性肺心病哮喘持续状态.根据患者的病理变化.综合治疗.效果显著。(2)在治疗过程中.要恰当选择抗生素和平喘药;对那些血液黏滞度增高的患者.要加用血液稀释疗法。(3)测定血液黏滞度和氧饱和度.可以指导治疗、估计预后.应当列为常规检查。  相似文献   
14.
Obstructive sleep apnea syndrome (OSAS) is a common condition characterized by repetitive sleep‐induced collapse of the upper airways. It is associated with increased risk for hypertension, ischemic heart disease, cerebral stroke, and traffic accidents. In contrast, gastroesophageal reflux disease (GERD) is a very common disorder defined as various symptoms or esophageal mucosal damage generated by the abnormal reflux of gastric contents into the esophagus. Patients with OSAS have been reported to have a high prevalence of gastroesophageal reflux (GER) symptoms. The increase of transdiaphragmatic pressure in parallel with the large negative intrathoracic pressure produced during apnea events may directly lead to GER. In addition, some studies have demonstrated improvement in GERD with the application of continuous positive airway pressure, most consistently effective treatment for OSAS. However, GER dose not occur with every apnea. Moreover, the common conditions observed in patients with OSAS, including obesity or alcohol ingestion, are also predisposing factors for GER. A more recent investigation in over 1000 subjects failed to show a causal link between both diseases. Thus, the potential relationship between OSAS and GERD remains controversial. Inconsistencies in definitions of both diseases or sampling biases may contribute to the confusing results.  相似文献   
15.
目的研究腹内压升高对大鼠中心静脉压和门静脉压的影响。方法将20只成年雄性SD大鼠分别通过颈静脉插管、穿刺门静脉主干法来测定中心静脉压和门静脉压,运用氮气气腹法制作大鼠腹内高压动物模型。建立气腹后分别在0、5、10、15、20、25、30、35、40、45mmHg压力值下测得中心静脉压和门静脉压。结果中心静脉压和腹内压之间的直线回归方程为Y=2.824+0.045X,相关系数r=0.984(P〈0.01);门静脉压和腹内压之间的直线回归方程为Y=8.887+0.939X,相关系数r=0.998(P〈0.01)。结论腹内压与中心静脉压和门静脉压有很好的相关性,可以根据腹内压监测中心静脉压和门静脉压的变化。  相似文献   
16.
AIM: The clinical significance of the urinary white blood cell (U-WBC) count and serum C-reactive protein (CRP) level was evaluated in an effort to improve the efficiency of prostate biopsies. METHODS: We enrolled 228 consecutive patients with serum prostate-specific antigen (PSA) ranging from 3.0 to 20.0 ng/mL, normal digital rectal examination findings, and who underwent prostate biopsies between January 2001 and August 2004. Of these, 157 patients had histologically confirmed benign prostatic disease and the remaining 71 patients had prostate cancer. Patients with a pretreatment U-WBC count < or =3 or >3/high power field were defined as non-pyuria and pyuria, respectively. The patients were also separated into two groups based on the serum CRP level prior to biopsy. Several clinical factors were compared among these subgroups. RESULTS: Inflammation was histologically detected at rates of 58.1% and 34.1% in the pyuria and non-pyuria groups, respectively (P = 0.0014). The rates of cancer detection were significantly lower in the pyuria, than in the non-pyuria group (P = 0.0384). The cancer detection rates did not significantly differ according to serum CRP levels prior to biopsy. CONCLUSION: The U-WBC count appears to be a reliable indicator of minute prostatic inflammation. The serum PSA level was elevated in patients with asymptomatic prostatitis. Counting U-WBC is a simple, convenient and non-invasive method that should be valuable part of routine urological examinations.  相似文献   
17.
目的探讨剖宫产术后深静脉血栓的护理经验。方法将2003年1月~2005年12月行剖宫产术的产妇76例,采取护理干预,加强饮食指导、抗凝血及溶栓护理。结果70例患者治愈,4例留有后遗症,2例转院,未跟踪报告。结论剖宫产术后易发生深静脉血栓;而高龄、经产、多胎、有产科并发症是其高危因素;应用护理措施进行积极干预,起到较好的预防作用,能保证产妇生命安全,提高产科护理质量。  相似文献   
18.
CS_2作业工人血清脂质过氧化水平与LDH同功酶谱研究张文昌,连祥霖,张连娜,杨乃富(福建医学院劳动卫生学教研室,福州350004)结果表明,高接触水平组(浓度为10.42~46.54mg/m3或Σmg·年≥50)血清LPO含量与对照比较,显著性增高?..  相似文献   
19.
The effects of daily oral administration of a high dose of 10 mg norethisterone acetate (NET-Ac.)/kg/day over 14 weeks on serum lipid and lipoprotein parameters as well as on blood coagulation were investigated in female monkeys (M. fascicularis). Measurements of lipids and lipoprotein cholesterol were performed in weeks —5 and — 1 before treatment and in weeks 4, 8 and 12 after treatment. In addition, various blood coagulation and fibrinolytic parameters were determined in weeks 11–14 after treatment with NET-Ac. Furthermore, the serum levels of norethisterone (NET) were determined in order to monitor the real systemic compound exposure and revealed that Cmax and AUC (0–3 h) values reached for norethisterone in this experiment in monkeys were about 25 times higher than those obtained after an oral contraceptive dose of NET-Ac. in women.

The results of lipid and lipoprotein cholesterol determinations showed decreases in serum total lipids, phospholipids, triglycerides and total cholesterol associated with similar decreases in HDL-, LDL- and VLDL-cholesterol fractions after NET-Ac.-treatment in monkeys. These effects were observed from week 4 onwards and maintained their magnitude up to week 12 after treatment. Since both HDL- and LDL-cholesterol fractions decreased, the HDL/LDL-ratio remained almost unchanged. Thus, the results obtained in this study after high-dose treatment with NET-Ac. in monkeys did not indicate any changes of lipid and lipoprotein parameters which in humans are supposed to be associated with an increased risk of cardiovascular lesions, namely a decrease in HDL- and increase in LDL-cholesterol fractions.

The results of blood coagulation and fibrinolytic parameters showed increased antithrombin-III and plasminogen levels besides minor changes in other parameters, thus indicating that NET-Ac. -treatment does not contribute to an increased risk of cardiovascular thrombotic events in the cynomolgus monkey.  相似文献   

20.
对13例体外循环病人进行了观察,发现体外循环后TXB2/6-keto-PGF1α显著增高,表明体外循环使血小板受损,而血小板受损是体外循环后失血的主要原因之一。  相似文献   
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