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171.
目的:探讨修复眼睑皮肤缺损的方法.方法:应用颞部眼轮匝肌皮瓣修复同侧眼睑皮肤软组织缺损10例.其中男 7例,女3例.缺损原因:疤痕切除后创面 7例,色素痣切除后创面1例,化学烧伤 2例.均为下睑皮肤软组织缺损.结果:所有病例皮瓣成活良好,外形效果满意.结论:颞部眼轮匝肌皮瓣血供可靠,转移方便,皮肤质地、厚度与眼睑皮肤相近,是一个修复眼睑皮肤缺损的理想的皮瓣.  相似文献   
172.
173.
目的 研究四逆汤中乌头类生物碱的溶出平衡和水解平衡。方法 利用电喷雾质谱分析,比较了制附子、四逆汤、四逆汤药渣和含有3种双酯型生物碱的混合对照品体系中的乌头碱类二萜生物碱。结果 在煎煮过程中双酯型生物碱溶解并发生水解反应,而脂类生物碱则难溶于水。乌头碱、中乌头碱、次乌头碱水溶性相近,但是次乌头碱在水中的热稳定性更高,C19二萜骨架上C3取代基(—OH或—H)的变化影响生物碱的稳定性。结论四逆汤中的乌头碱类生物碱的种类及含量由其溶解性和化学稳定性共同决定。  相似文献   
174.
目的:研究不同剂量美维松对膈肌和拇收肌的抑制时程与恢复过程。方法:30例ASAⅠ级的成年手术患者,按美维松用量分成两组,Ⅰ组:0.16mg/kg,Ⅱ组:0.20mg/kg,每组15例。同步测定跨膈肌压(Pdi)和拇收肌对连续四次刺激(TOF)反应的T1(APT1)及TOFr值。结果:显示两组APT1最大抑制相近,是Pdi的1.7倍。Pdi达到最大抑制及恢复到75%的时间比APT1快得多。结论:提示美维松对膈肌收缩功能的抑制比拇收肌差,但恢复迅速。  相似文献   
175.
 Infantile myofibromatosis is a mesenchymal tumor most commonly seen in infancy. The tumors have a variable appearance on CT/MR and often simulate a more aggressive neoplasm. This report describes CT/MR findings in cases of infantile myofibromatosis with pathologic correlation. Discussion into the success of imaging in suggesting the correct diagnosis is also addressed. Infantile myofibromatosis is a mesenchymal disorder of infancy characterized by the presence of tumorous nodules in the skin, subcutaneous tissue, muscle, viscera, and bone. Cases of solitary and multiple lesions have been described. We present the clinical, histologic, and radiographic findings of one case of the solitary form of infantile myofibromatosis that was recently diagnosed at our hospital.  相似文献   
176.
Skeletal muscle extracellular carbonic anhydrase III was investigated in anesthetized rats by a microdialysis technique. A small dialysis probe was inserted into the tibialis anterior (TA) muscle and perfused continuously. Perfusates were collected before and during muscle contraction, induced by electrical stimulation of the muscle or of the sciatic nerve. In the perfusate of resting normal and denervated muscle, the concentration of CA III was 10 to 12 ng/mL, as measured by a radioimmunosorbent technique. During contractile activity, the concentrations of CA III increased markedly in the normal and denervated muscle. A TA muscle suspended in physiological saline behaved similarly, even though the leakage before and during contraction was higher than in vivo. The results show that skeletal muscle leaks CA III both in vivo and in vitro, a leakage which was markedly increased by contractile activity. The microdialysis technique should also be useful in humans to study the efflux of various proteins from different kinds of diseased or fatigued muscles.  相似文献   
177.
Background. Partial harvesting of the left internal mammary artery (LIMA) is a widespread technique used during minimally invasive coronary operations performed through a left anterior small thoracotomy. The influence of persisting LIMA branches was investigated to evaluate their effect on the blood flow of the left anterior descending artery.

Methods. Thirty patients, 15 with totally (group A) and 15 with partially (group B) harvested LIMAs, were evaluated. All the patients underwent postoperative angiography, during which a flow map of the LIMA was performed. The average peak velocity and the diastolic-to-systolic peak velocity ratio were recorded. The LIMA graft flow pattern was recorded in the proximal and distal thirds of the artery. Intramammary adenosine (12 to 14 μg) was injected and the average peak velocities before and after injection were calculated.

Results. The average peak velocity was similar in both groups in the proximal and distal thirds of the LIMA (25 ± 7 and 26 ± 5 cm/sec, respectively, in group A versus 27 ± 5 and 25 ± 5 cm/sec, respectively in group B; p = NS). The diastolic-to-systolic peak velocity ratio was similar proximally (0.78 ± 0.3 in group A versus 0.69 ± 0.3 cm/s in group B; p = NS), but not distally (1.72 ± 0.1 in group A versus 0.97 ± 0.3 in group B; p < 0.0005). The LIMA graft flow reserve was similar both proximally and distally (2.6 ± 0.6 and 2.5 ± 0.3 cm/s, respectively, in group A versus 2.6 ± 0.5 and 2.6 ± 0.3 cm/s, respectively, in group B; p = NS).

Conclusions. The persistence of LIMA branches does not influence the blood flow of the left anterior descending artery after acute adenosine-induced myocardial hyperemia. If a left anterior small thoracotomy is used in left anterior descending artery direct revascularization, complete LIMA harvesting is not mandatory and depends on the personal preference of the surgeon.  相似文献   

178.
Summary Insulin resistance and a defective insulin activation of the enzyme glycogen synthase in skeletal muscle during euglycaemia may have important pathophysiological implications in Type 2 (non-insulin-dependent) diabetes mellitus. Hyperglycaemia may serve to compensate for these defects in Type 2 diabetes by increasing glucose disposal through a mass action effect. In the present study, rates of whole-body glucose oxidation and glucose storage were measured during fasting hyperglycaemia and isoglycaemic insulin infusion (40 mU·m–2min–1, 3 h) in 12 patients with Type 2 diabetes. Eleven control subjects were studied during euglycaemia. Biopsies were taken from the vastus lateralis muscle. Fasting and insulin-stimulated glucose oxidation, glucose storage and muscle glycogen synthase activation were all fully compensated (normalized) during hyperglycaemia in the diabetic patients. The insulin-stimulated increase in muscle glycogen content was the same in the diabetic patients and in the control subjects. Besides hyperglycaemia, the diabetic patients had elevated muscle free glucose and glucose 6-phosphate concentrations. A positive correlation was demonstrated between intracellular free glucose concentration and muscle glycogen synthase fractional velocity insulin activation (0.1 mmol/l glucose 6-phosphate: r=0.65, p<0.02 and 0.0 mmol/l glucose 6-phosphate: r= 0.91, p<0.0001). In conclusion, this study indicates an important role for hyperglycaemia and elevated muscle free glucose and glucose 6-phosphate concentrations in compensating (normalizing) intracellular glucose metabolism and skeletal muscle glycogen synthase activation in Type 2 diabetes.  相似文献   
179.
Summary Since it has been suggested that gastric resections are followed by changes in bone metabolism, the aim of our study was to determine the biochemical parameters of bone metabolism and radial and lumbar bone density in 15 male ulcus patients treated by partial gastrectomy (Billroth II). Comparing the data with those of a corresponding control group, the lumbar bone density measured by quantitative computed tomography was statistically significantly lower (P < 0.04) in the patient group, whereas the peripheral bone mass of the distal part of the nondominant forearm measured by single-photon absorptiometry showed no statistically significant difference. In addition, a marked increase in alkaline phosphatase (P < 0.002) and urinary excretion of hydroxyproline (P < 0.003) was found in the gastrectomy group, whereas the 25-hydroxy-vitamin D levels were found to be significantly decreased (P < 0.04). Osteocalcin, a biochemical marker for osteoblast activity, and the carboxy-terminal propeptide of type I procollagen (PICP), a marker of collagen formation, were slightly but not significantly higher in gastrectomy-treated patients. The serum parathyroid hormone levels were similar in both groups. As none of the patients had any radiologic evidence of osteopenia, the changes in biochemical parameters of bone metabolism and bone mass in patients who had undergone partial gastrectomy could be a marker of latent bone loss.Abbreviations DPA/SPA dual/single-photon absorptiometry - BMD bone mineral density - QCT quantitative computed tomography - PICP carboxy-terminal propeptide of type I procollagen - 250HD3 25-hydroxy-vitamin D - iPTH parathyroid hormone - OC osteocalcin - BMC bone mineral content  相似文献   
180.
One hundred ninety-eight postmenopausal women (aged 50–65 years) with vertebral bone density (VBD) 1 SD below the mean value for normal, age-matched, postmenopausal subjects were enrolled in six Italian centers and 134 completed 2 years of treatment. All subjects were randomly allocated to a 2-year treatment with oral ipriflavone (200 mg t.i.d.) or a matching placebo, according to a double-blind, parallel group design. All patients also received an oral daily calcium supplement of 1 g as calcium carbonate. VBD and markers of bone turnover were measured at baseline, and every 6 months. A complete routine analysis of liver and kidney functions along with hematological parameters were measured before and at the end of treatment period. The valid completers analysis showed a significant increase of VBD in ipriflavone-treated women with average percent changes of +1.4 after 1 year, and +1% at the end of treatment period (P < 0.05). The placebo group presented a significant decrease of VBD after 2 years of treatment (P < 0.05). The difference between treatments was significant (P < 0.01). The intention to treat analysis confirmed the significant decrease of VBD in the placebo group, with no changes in ipriflavone-treated women. Skeletal ALP significantly decreased in ipriflavone-treated women (P < 0.05). Serum BGP and urine HOP/Cr showed a significant decrease only in ipriflavone-treated women, suggesting an inhibitory effect on bone turnover rate. Adverse reactions, mainly gastrointestinal, occurred to a similar extent in the two treatment groups. The evaluation of patients' compliance, assessed by residual tablets count, revealed a drug intake of more than 80% after 2 years in 92.5% and 92.8% of patients treated with ipriflavone or placebo, respectively. This study demonstrates that ipriflavone can prevent bone loss in postmenopausal women with low bone mass. Received: 1 April 1996 / Accepted: 5 March 1997  相似文献   
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