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991.
动脉内溶栓治疗急性脑梗死 总被引:5,自引:0,他引:5
为了前瞻性研究局部动脉内溶栓治疗急性脑梗死的疗效,应用超导技术对37例急性脑梗死病临近梗死部位的脑血管内注入溶栓药物治疗。其中22例使用蝮蛇抗栓酶3号,15例使用尿激酶溶栓,结果:27.03%的患者在6小时内溶栓,24.32%在7~12小时内,21.63%在13-24小时内,24.32%在25~48小时内,2.7%在48小时以后溶栓,溶栓后症状明显好转者占59.5%,好转者21.6%,无改善18. 相似文献
992.
对外科手术中意外低体温影响因素的观察研究 总被引:1,自引:0,他引:1
对30例神经外科择期手术体温正常患者术中影响体温变化的因素进行观察。在国麻醉期持续监测体温、室温及相对湿度,记录液体输注量及尿量。结果显示,当室温≤24℃、手术时间> 5小时、输注室温下人液量≥(651±121)ml/h时,可导致意外低体温。所以,麻醉中体温监测是必不可少的。 相似文献
993.
Yang SS Chen CY Wei CB Lin YT 《Zhonghua Minguo wei sheng wu ji mian yi xue za zhi = Chinese journal of microbiology and immunology》1996,29(4):185-196
Several microbes were isolated from the contaminated fuel-oil in Taiwan and the microbial corrosion of aluminum alloy A356-T6 was tested by MIL-STD-810E test method. Penicillium sp. AM-F5 and Cladosporium resinac ATCC 22712 had significant adsorption and pitting on the surface of aluminum alloy, Pseudomonas acruginosa AM-B5 had weak adsorption and some precipitation in the bottom, and Candida sp. AM-Y1 had the less adsorption and few cavities formation on the surface. pH of the aqueous phase decreased 0.3 to 0.7 unit for 4 months of incubation. The corrosion of aluminum alloy was very significant in the cultures of Penicillium sp. AM-F2, Penicillium sp. AM-F5 and C. resinac ATCC 22712. The major metabolites in the aqueous phase with the inoculation of C. resinac were citric acid and oxalic acid, while succinic acid and fumaric acid were the minors. 相似文献
994.
C. -T. Yang H. -C. Lin M. -C. Lin C. -H. Wang C. -H. Lee H. -P. Kuo 《European journal of clinical pharmacology》1996,49(5):341-345
Objective: The effect of 2-adrenoceptor agonist-induced hypokalaemia on cardiac arrhythmias might be exacerbated during exercise, especially in patients with more compromised airway function.
Methods: To evaluate the effect of 2-adrenoceptor agonists on plasma potassium and cardiopulmonary function during exercise, two identical submaximal treadmill exercise tests were performed, at least 48 h apart, by 13 patients with moderate to severe COPD (11 men and 2 women, mean age 66 y, mean FEV1/FVC ratio 48.9 (2.8)%) 30 min after they had received nebulised fenoterol or salbutamol (2 mg). The experiment was done as a randomised, double-blind, crossover trial after an initial baseline study with vehicle (0.45% saline). Plasma potassium concentration, spirometry and the degree of breathlessness (Borg scale) were measured before treatment and immediately after exercise; oxygen saturation, QTc interval and cardiac rhythm were monitored continuously before, during and for 30 min after exercise.
Results: After the saline control, exercise caused an increase in Borg rating (of 4.9), a premature ventricular contractions (VPC) (2.8 beats/min), and a fall in oxygen saturation (-6.7%), but no significant change in plasma potassium (+0.04 mEq·dl–1), FEV1 or QTc interval. Inhalation of fenoterol and salbutamol did not affect QTc interval, Borg scale or VPC frequency at rest, but significantly increased the duration of exercise undertaken to reach the submaximal levels (786 s, versus 783 s) compared to the vehicle control. Following exercise, plasma potassium fell after fenoterol by 0.2 mEq·dl–1 and it increased after salbutamol by 0.1 mEq·dl–1 compared to baseline levels. Plasma potassium after exercise was significantly lower after fenoterol (3.2 mEq·dl–1) compared to the saline control (3.7 mEq · dl–1) and salbutamol (3.6 mEq · dl–1). Neither fenoterol nor salbutamol had any significant effect on the change in FEV1, oxygen saturation, Borg scale, frequency of VPCs or QTc interval during or after exercise compared to the saline control.
Conclusion: When compared to salbutamol 2 mg, fenoterol 2 mg caused more marked hypokalaemia but no significant difference in cardiopulmonary response in patients with COPD during exercise. 相似文献
995.
Purpose. The human plasma binding of cyclosporin A was studied in vitro using the technique of microdialysis. The effect of temperature on the overall binding interaction between cyclosporin A and human plasma was also investigated.
Methods. Flow-through loop-type microdialysis probes were constructed from fused silica tubing and regenerated cellulose tubing with a MWCO of 13000 daltons. Probes were perfused with phosphate buffer (0.5 µl/min) and the concentration of 3H-cyclosporin A in the well-mixed medium (plasma or buffer) was 1200 ng/ml. Relative recoveries of cyclosporin A from plasma or buffer were determined for each probe by separate experiments to measure the solute gain or loss with reference to the perfusate.
Results. Recoveries determined by loss were significantly greater than those determined by gain and in each case temperature dependent, with higher recoveries at higher temperatures. The plasma free fraction of cyclosporin A calculated from the recovery data and the perfusate to plasma concentration ratios was dependent on temperature in a log-linear fashion. Mean ± s.d. plasma free fractions expressed in percent were 33.5 ± 4.6, 17.9 ± 3.6, 6.2 ± 0.8, 3.0 ± 0.6, and 1.5 ± 0.2 at temperatures of 4, 10, 20, 30, and 37°C, respectively. Assuming that the enthalpy of binding is constant over the temperature range studied and pseudo-first order conditions exist, the binding reaction at these temperatures was spontaneous, endothermic (H = 74.0 kJ/mole), and entropically driven (S = 0.274 kJ/mole/deg).
Conclusions. These results show that the free fraction of cyclosporin A in human plasma is dependent on temperature with the fraction unbound decreasing with temperature in the range of 4 to 37°C. The thermodynamic parameters for the binding of cyclosporin A to plasma components indicate that the reaction is a spontaneous endothermic reaction that is mainly entropy driven, similar to the partitioning of lipophilic molecules from an aqueous to a hydrophobic phase. Moreover, these results show that microdialysis is a feasible method to determine the binding interactions between plasma and cyclosporin A, which indicates the method may be suitable for other difficult binding studies where the solutes have nonspecific binding to separation devices. 相似文献
996.
We present a case of a giant colonic pseudolipoma in a patient with colonic dysmotility due to chronic Ogilvie's syndrome. 相似文献
997.
R. Lupu M. Cardillo C. Cho L. Harris M. Hijazi C. Perez K. Rosenberg D. Yang C. Tang 《Breast cancer research and treatment》1996,38(1):57-66
Summary TheerbB-2 receptor plays an important role in the prognosis of breast cancer and is expressed at high levels in nearly 30% of tumors in breast cancer patients. While evidence accumulates to support the relationship betweenerbB-2 overexpression and poor overall survival in human breast cancer, understanding of the biological consequence(s) oferbB-2 overexpression remains elusive. The discovery ofheregulin has allowed us to identify a number of related but distinct biological endpoints which appear responsive to signal transduction through theerbB-2/4 receptor. These endpoints of growth, invasiveness, and differentiation have clear implications for the emergence, maintenance, and/or control of malignancy, and represent established endpoints in the assessment of malignant progression in human breast cancer. Preliminary studiesin vitro have shown thatheregulin induces a biphasic growth effect on cells witherbB-2 overexpression. Interestingly, we observed that expression ofheregulin correlates with a more aggressive/invasive, vimentin-positive phenotype in breast cancer cells lines. Therefore, we have postulated thatheregulin is involved in breast cancer tumor progression. We have shown thatheregulin inducesin vitro chemoinvasion and chemotaxis of breast cancer cells as well as growth in an anchorage dependent and independent manner. Interestingly, aheregulin neutralizing antibody inhibits chemotaxis and results in cell growth inhibition and blockade of the invasive phenotype. Strikingly, genetically engineered cells which constitutively expressheregulin demonstrate critical phenotypic changes that are associated with a more aggressive phenotype. Specifically, these cells are no longer dependent on estrogen for growth and are resistant to tamoxifenin vitro andin vivo, and moreover these cells metastasize to lymph nodes in athymic nude mice. These tumors appear to have lostbcl-2 expression as compared with the control tumors. In addition, presumably by activation/regulation of topoisomerase II, theheregulin-transfected cells become exquisitely sensitive to doxorubicin and VP-16. Clearly, mechanistic aspects of theerbB-2/4 andheregulin interaction need to be understood from a therapeutic standpoint which could provide additional insights into synergistic treatments for certain patients, or improve treatment regimens for a large number of women. The study ofheregulin and its co-expression witherbB-2/4 receptor and the assessment of its involvement in the progression from the in situ stage of breast tumors to the invasive one will additionally increase the relevance ofheregulin as a prognostic/diagnostic factor. We believe that our studies provide new insights into breast cancer diagnosis, prognosis, and treatment.Presented at the symposium "New Approaches in the Therapy of Breast Cancer", Georgetown University Medical Center, Washington DC, October 1994, generously supported by an education grant from Bristol-Myers Squibb. 相似文献
998.
Braun KL Yang H Look MA Onaka AT Horiuchi BY 《Asian American and Pacific Islander journal of health》1996,4(4):352-362
PURPOSE OF THE PAPER: The purpose of this paper is to test if the previously identified disparity in mortality rates among full Hawaiians, part Hawaiians, and nonHawaiians in the state of Hawaii has continued into the 1990s. SUMMARY OF METHODS UTILIZED: Based on Hawaii vital records and population data, standardized agespecific mortality rates by cause and 95% confidence intervals were estimated. PRINCIPAL FINDINGS: The most striking finding was the significant differences in mortality rates in four age strata 4554, 5564, 6574, and 7584 with mortality rates highest for full Hawaiians, lowest for nonHawaiians, and intermediate for part Hawaiians. CONCLUSIONS: Findings suggest that Native Hawaiians continue to be at greater risk of death compared with nonHawaiians, with full Hawaiians at greatest risk. RELEVANCE TO ASIAN PACIFIC ISLANDER AMERICAN POPULATIONS: Asian and Pacific Islander Americans have been called the model minority. These data provide evidence that Native Hawaiians, especially full Hawaiians, have dramatically higher mortality rates than nonHawaiians and merit special attention. 相似文献
999.
Michael G. Irwin Robert C. H. Campbell Tsui Siu Lun Joseph C. S. Yang 《Journal canadien d'anesthésie》1996,43(9):919-924
Purpose
The purpose of this study was to determine whether alfentanil given by a pharmacokinetic-based target controlled infusion (TCI) system under patient control is a suitable analgesic technique for extracorporeal shock wave lithotripsy (ESWL).Methods
The design was an open, unblinded, noncomparative, prospective study. Forty outpatients undergoing ESWL were given patient maintained alfentanil TCI. Pain, nausea and sedation were assessed every 300 shocks. Vital signs were recorded every three minutes, pulse oximetry and electrocardiography being monitored continuously. Blood alfentanil concentration was measured for comparison with the predicted value.Results
Alfentanil consumption (median 1.34 mg, range 0.8–3.6) and measured levels following treatment (median 60 ng·ml?1, range 15.6–134.3) varied widely. The precision of the TCI system and the median prediction error (bias) were both 49%. The median of pain scores recorded during treatment was 4 (range 0–8). The median respiration rate was 15 bpm (range 10–23), three patients required oxygen (SaO2 < 92%) Cardiovascular measurements were stable and there was no excessive sedation. The incidence of nausea was 15%. All patients were ready for hospital discharge within one hour following treatment.Conclusions
Patient maintained alfentanil TCI provides good analgesia for ESWL in the majority of patients with little sedation. Respiratory depression is uncommon but supplementary oxygen should be given prophylactically. There is considerable interindividual variation in demand for alfentanil indicating the usefulness of the patient control method. The TCI system underestimated alfentanil blood concentrations but this did not affect its clinical usefulness. 相似文献1000.
Homer Yang 《Journal canadien d'anesthésie》1996,43(10):1041-1051