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171.
Cyclopenta-polycyclic aromatic hydrocarbons (cyclopenta-PAHs) are a group of compounds that have been detected as environmental pollutants. Perturbation molecular orbital (PMO) calculations on their presumed ultimate carcinogenic metabolites, the cyclopenta-PAH expoxides, predict that they may have a greater biological hazard than the classic PAHs. 相似文献
172.
本文用放射免疫分析法(RTA)测定了泰和母鸡在排卵周期和抱窝的不同生殖阶段,血浆“黄体生成素类似物”(“LH”)和孕酮(P)的浓度。结果表明:母鸡在排卵周期血浆“LH”和P的平均值分别为3.67±0.60ng/ml(x±SE)和459.50±30.87pg/ml,排卵前6~3h,血浆“LH”和P均出现浓度高峰,其峰值比相应的平均值高出1.1和1.3倍,差异非常显著(P<0.01)。抱窝鸡血浆“LH”和P在24h内的平均值分别为2.27±0.22ng/ml和319.46±12.15pg/ml,显著地低于母鸡在排卵周期的平均值(P<0.05),且在24h内的不同时间,未见有浓度高峰出现。 相似文献
173.
J D Cox T F Pajak V A Marcial L Coia M Mohiuddin K K Fu H Selim P Rubin H Ortiz 《International journal of radiation oncology, biology, physics》1991,20(6):1191-1195
A prospective, randomized, multi-institutional, Phase I(LE)/II trial of HFX was conducted by the RTOG between 1983 and 1987. Patients with histologically proven, inoperable squamous cell carcinoma of the upper respiratory and digestive tracts stratified by site, nodal status, and performance status, were assigned to one of three arms, were assigned to one of three arms, 67.2 Gy, 72.0 Gy, or 76.8 Gy. Fractions of 1.2 Gy were given twice daily, 5 days per week: intervals of 4 to 8 hours were permitted between fractions. After acceptable rates of acute normal tissue effects were found, the randomization was changed to evaluate a new higher total dose, 81.6 Gy. Of 479 patients entered, 447 were analyzed, 63 on 67.2 Gy, 129 on 72.0 Gy, 117 on 76.8 Gy, and 138 on 81.6 Gy. The treatment arms were well balanced with respect to pretreatment characteristics. Acute reactions consisted almost entirely of pseudomembranous inflammation. "Severe" (Grade 3) acute reactions were reported in 33% to 41% and grade 4 reactions were found in 0 to 3% of patients, with no differences in frequencies among the four arms. Toxicities that developed or persisted beyond 90 days after the first treatment (408 patients evaluable greater than 90 days) did not differ among arms: grade 3+ reactions occurred in 10% to 14%, and grade 4+ effects (necroses) were reported in 5% at 67.2 Gy, 3% at 72.0 Gy, 7% at 76.8 Gy, and 2% at 81.6 Gy. Grade 3+ acute reactions occurred in 40% of patients when the interfraction interval was less than or equal to 4.5 hours versus 31% with greater than 4.5 hours (p = .03). Interfraction intervals less than or equal to 4.5 hours were associated with higher frequencies of grade 4+ late effects in all four arms, 8% of 197 patients with less than or equal to 4.5 hours versus 1% of 211 patients with greater than 4.5 hours. Estimates of late toxicity at 1, 2, and 3 years were 5.5%, 9.8%, and 15.4% with intervals less than or equal to 4.5 hours, versus 1.7% at all three periods for greater than 4.5 hours (p = .006). Local-regional control at 2 years was 25% for the assigned dose of 67.2 Gy compared to 43% to 45% for the three higher doses (p = .01), but a similar comparison for survival showed no significant difference (p = .35). There was no evidence for an effect of interfraction interval on either local-regional control (p = .38) or survival (p = .28).(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
174.
Fourteen points superficial bloodflow (SBF) of the skin and tongue in 55 patients with acute myocardial infarction (AMI) were measured at 12, 24, 36, 48, 60 hours and 3, 5, 7, 10, 14, 21, 28 days after AMI by LDF (PF2). The dynamic study on multiple points SBF of 576 times showed that (1) The mean SBF of skin was 1.0 +/- 0.04 (V) at 12 hours after AMI. It occupied 70.5% in the normal control. After therapy at 48 hours of AMI, the mean SBF was increased to 1.20 +/- 0.03 (V), and approximated 85.9% of the control. (2) The mean SBF in patients with cardiogenic shock was 1.04 +/- 0.05 (V), and it was significantly lower than that without complications (P less than 0.01). The mean SBF showed a negative correlation with the nailfold microcirculatory values (P less than 0.0025). There was a negative correlation between "Tanzhong" SBF and cardiac muscle enzyme CPK, GOT, LDH (P less than 0.05). (3) The SBF of acupuncture point "Tanzhong, Erxin" related to the heart might more sensitively represent the cardiac condition in AMI. (4) The SBF of tongue was negatively correlated with GOT (P less than 0.05). (5) Continual peripheral microcirculatory observation and electrocardiographic monitoring would be helpful in the diagnosis and treatment of earlier complications of AMI in order to reduce the mortality. 相似文献
175.
In our series of 256 nonepithelial tumors involving the nasal cavity, paranasal sinuses and nasopharynx, 21 were apparently primary malignant lymphomas, including 17 ordinary lymphomas and 4 cases of "midline malignant reticulosis." Of the 15 patients who had ordinary lymphomas and had adequate follow-up, 8 died of lymphoma, 4 were living with disseminated disease, 1 died of other causes with persistent lymphoma and only 2 (13%) had no evidence of recurrence at 8 and 9 years after diagnosis. The tumor was controlled in its primary site by radiotherapy in 13 of 14 patients; however, all but 2 of these patients eventually developed disseminated disease. Of the 3 patients who had midline malignant reticulosis (MMR) and had adequate follow-up, all died of disease. MMR represents an unusual variant of malignant lymphoma and often produces the clinical picture of lethal midline granuloma. 相似文献
176.
高效液相色谱法测定美洛昔康胶囊的含量 总被引:1,自引:0,他引:1
目的 :建立反相高效液相色谱法测定美洛昔康胶囊中美洛昔康的含量。方法 :采用LichrosorbC18色谱柱 (5 μm,4 .6mm× 2 0 0mm) ,以吡罗昔康为内标 ,甲醇 乙腈 0 .0 9mol·L-1庚烷磺酸钠溶液 冰醋酸 (5 4∶8∶37∶1)为流动相 ,流速为0 .9mL·min-1,检测波长为 35 2nm ,柱温为室温。结果 :美洛昔康在 8~ 4 8mg·L-1范围内呈良好的线性关系 ,r =0 .9999,平均回收率为 99.78% ,RSD为 0 .96 %。结论 :该法简便 ,快速 ,专属性好 ,结果准确 ,可靠。 相似文献
177.
RP-HPLC测定上感口服液中丹皮酚含量 总被引:2,自引:2,他引:2
应用RP -HPLC测定上感口服液中丹皮酚的含量。采用ODS色普柱 ( 2 5 0mm× 4 6mm ,5 μm) ,甲醇-水 -冰醋酸 ( 65∶35∶0 5 )为流动相 ,检测波长为 2 74nm。丹皮酚在 2 5~ 30 μg ml-1浓度范围内呈良好线性关系 (r =0 9999) ,平均回收率为 95 7%,RSD =2 1%(n =6)。方法准确、灵敏 ,回收率高。 相似文献
178.
179.
傅宏 《中国中医骨伤科杂志》2003,11(3):29-32
目的 :研究一种新的股骨粗隆间骨折的固定系统 ,使之对此骨折固定更加简便、坚固、应用更广泛、提高治疗效果。方法 :自行设计一套超低角螺钉 -加压钉系统 ,在 2 4根尸体股骨干上段进行加载试验和重复载荷试验 ,然后用于 1 3 0例临床病人 ,评价其骨折愈合时间和并发症。结果 :生物力学测试表明 ,本固定系统对抗破坏载荷和耐疲劳性能优于 1 40°角钢板、麦氏鹅头钉、多枚斯氏针固定方法。临床结果表明 ,采用本系统固定的患者 ,骨折临床愈合时间短 ,可用于合并多种疾病的老年人 ,未发生手术并发症 ,术后功能优良率达到87。 7%。结论 :超低角螺钉系统治疗股骨粗隆间骨折具有操作简单 ,损伤小 ,合并症少 ,较其它固定物更加牢固 ,更加符合股骨粗隆部的力学特征 ,且具有操作简单、损伤小 ,应用更广泛 ,更适合应用于老年人及有较多合并疾病的患者的优点。 相似文献
180.
目的 研究可溶性血管细胞黏附分子 1(solublevascularcelladhesionmolecule - 1,sVCAM - 1)在妊高征发病中的作用。方法 用酶联免疫吸附法 (ELISA)测定 6 7例孕妇血清中sVCAM - 1水平 ,其中正常妊娠组 15例 ,妊高征组 5 2例。结果 中、重度妊高征患者血中sV CAM - 1水平显著高于正常妊娠组 (P <0 .0 1) ;轻度妊高征患者与正常妊娠组相比 ,虽无统计学差异 ,但有升高趋势 ;妊高征组产后该指标下降 ,与正常妊娠组比较无显著性差异 (P >0 0 5 )。sVCAM - 1浓度与平均动脉压呈正相关 (r =0 .5 4 2 ,P <0 .0 1)。结论 妊高征患者血中sVCAM - 1水平升高 ,表明内皮细胞损伤在妊高征的发病中起重要作用。 相似文献