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81.
Two new prenylated flavones, artocarpones A and B (1 and 2), and seven known isoprenylated flavonoids, artonin A (3), cycloheterophyllin (4), artoindonesianin E (5), artoindonesianin R (6), heterophyllin (7), heteroflavanone C (8), and artoindonesianin A-2 (9), have been isolated from the stem bark of Artocarpus champeden. Their structures were determined by spectroscopic analysis. Among the compounds isolated, 8 had the most potent inhibitory activity against the growth of Plasmodium falciparum 3D7 clone, with an IC50 value of 1 nmol L−1.  相似文献   
82.
Muscle relaxant activities of six compounds isolated from Malaysian medicinal plants were investigated on the smooth muscles of the rat aorta and longitudinal muscle of the guinea-pig ileum. Except for goniothalamin, the other five compounds exhibited varying degrees of muscle relaxant activities on the two smooth muscles. Dicentrine, isocorydine, altholactone and usnic acid reduced the contractions to KCI and phenylephrine in the rat aorta, whilst atranorin slightly reduced the contractions to phenylephrine but not KCI. In addition, dicentrine and isocorydine markedly reduced the contractile response to phenylephrine in Ca2+-free Krebs solution. In the longitudinal muscle of the guinea-pig ileum, altholactone, atranorin, dicentrine and isocorydine inhibited to a greater extent the phasic than the tonic responses to KCI. All four compounds similarly inhibited the contractions induced by ACh. The results suggest that the relaxant activities of the compounds are attributed mainly to inhibition of Ca2+ influx via the calcium channels in the membrane of the smooth muscles. Furthermore, the greater sensitivity of dicentrine, isocorydine and altholactone against phenylephrine-induced contractions or KCI-induced phasic contractions are due to their abilities to inhibit intracellular Ca2+ release in these muscles.  相似文献   
83.
Classical least-squares (CLS) and principal component regression (PCR) techniques were proposed for the simultaneous analysis of tablets containing acetaminophen and caffeine without using a chemical separation procedure. The chemometric calibrations were prepared by measuring the absorbances values at the 15 wavelengths in the spectral region 215-285 nm and by using a training set of the mixtures of both drugs in 0.1 M HCI. The obtained chemometric calibrations were used for the estimation of acetaminophen and caffeine in samples. The numerical calculations were performed with the 'MAPLE V' software. By applying two techniques to synthetic mixtures, the mean recoveries and the relative standard deviations in the CLS and PCR techniques were found as 99.5 and 1.29, 99.7 and 1.00% for acetaminophen and 99.9 and 1.92, 100.0 and 1.178% for caffeine, respectively. Our results were compared with those obtained previously by one of us considering HPLC method as a reference method. These two methods were successfully applied to a pharmaceutical tablet formulation of two drugs.  相似文献   
84.
85.
Infantile spasms are an age-related epileptic syndrome of infancy and are characterized by the combination of clusters of epileptic spasms and specific electroencephalographic findings. The etiology and the pathogenesis of the disease is still unclear. Prolactin has been thought to be specifically related to epileptic seizures. To investigate the possible mechanism of prolactin secretion in infantile spasms cerebrospinal fluid prolactin levels were examined. Fifteen patients with infantile spasms (10 females and five males), 3-16 months of age, were evaluated and compared with age- and sex-matched control subject. Cerebrospinal fluid samples for prolactin were obtained before and after treatment. The mean prolactin levels in the cerebrospinal fluid of the patients before therapy (3.25 +/- 1.48 ng/mL) was higher than the control group (2.38 +/- 0.89 ng/mL), and the difference between the two groups was statistically significant (P < 0.001). The mean prolactin level in the cerebrospinal fluid of the patients after therapy (4.69 +/- 1.47 ng/mL) was demonstrated to be higher than the mean prolactin level before therapy (3.25 +/- 1.48 ng/mL) and the difference between the two groups was statistically significant (P = 0.037). Elevation of cerebrospinal fluid prolactin levels before and after treatment in patients with infantile spasms provided evidence that the cerebrospinal fluid prolactin level is related with neuronal injury.  相似文献   
86.
87.
末期癌患者的预后自觉度、生存意志与医护期望   总被引:4,自引:0,他引:4  
目的:透过对末期癌患者的访问和研究,探讨他们对病情严重度的认知和预后自觉程度,如何影响其生存意志,及其在生命的晚期的医护期望.对象与方法:对象是首次入住安宁护理病区的20名病人,共6男14女,平均年龄是68.9岁,全确诊为扩散性末期癌症.以半结构的面谈方式,让癌患者诉说其疾病及生活经验,内容包括住院的期望,及身、心、灵等方面的关注.采用范甘的"查验解说"进行了资料分析.结果:所有病人均能说出所患疾病,但没有一人是直接从医生口中确定自己的诊断.病人从自己的病征病状,院方给予的诊疗方案、及医护人员/家属的神情等途径"意会"到自己的病情严峻.病人的生存意志有三种表现:拼命求生、无奈接受现实和要求加速死亡.生存意志与病人的生存质量相关,也影响他们对医护的期望.结论:医护人员要在"保密避谈"及"坦诚沟通"间取得平衡,给予病人最佳临终护理.研究结果显示医护人员跟终末期病患者"坦诚沟通"并非不可行,也不一定如传统观念般带来不良后果.反之,能够了解病人所关注和关心的事情,帮助他们安然走过最后一段日子,才符合临终关怀的宗旨.医护人员跟病人坦诚交谈有助增强彼此的互信关系,建立合理的医护期望和改善病人的生存质量.  相似文献   
88.
Avulsion fracture of the base of the second metacarpal is an unusual injury, and the cause in the few cases reported in the literature was a fall on a volarly flexed wrist. A case of this rare injury suffered in a sport related accident by a semiprofessional rugby player is reported. It was treated with open reduction and internal fixation after failure of conservative management.  相似文献   
89.
BACKGROUND: Hematopoietic growth factors (HGFs) have been used to reduce the neutropenic complications of cytotoxic chemotherapy so that higher doses may be given. The authors have previously shown that endogenous serum granulocyte-colony stimulating factor (G-CSF) and granulocyte-macrophage-colony stimulating factor (GM-CSF) levels at night (p.m.) were significantly higher than those in the morning (a.m.). METHODS: Twenty-four patients with soft tissue or bone sarcoma who were treated with high dose ifosfamide-based chemotherapy were enrolled in this study. Patients were randomized to either a.m. or p.m. treatment. GM-CSF was administered at a dose of 5 microg/kg/day at 10 a.m. or 10 p.m., beginning 36-48 hours after the last chemotherapy dose. GM-CSF therapy was continued until the neutrophil count exceeded 1,000/mm3 for 2 consecutive days. Leukocyte, neutrophil, monocyte, and platelet counts were measured immediately before GM-CSF administration and exactly 12 hours after the first dose of GM-CSF, and every 24 hours until 3 days after the cessation of GM-CSF. RESULTS: The mean duration of Grade 3-4 neutropenia was 5.3 +/- 0.4 days for the a.m. treatment arm and 6.5 +/- 0.3 days for the p.m. treatment arm (P = 0.017). Although the duration of neutropenia in the a.m. arm was significantly shorter than in the p.m. arm, there were no differences related to the number of febrile neutropenic episodes or the duration of antibiotic administration. Also, there were no differences in the side effects observed in the a.m. and p.m. arms. CONCLUSIONS: The finding of 1.2 days' difference in the duration of Grade 3-4 neutropenia warrants further study of chronotherapy with HGFs.  相似文献   
90.
Mitomycin C prevents strictures in caustic esophageal burns in rats   总被引:2,自引:0,他引:2  
BACKGROUND: Caustic esophageal injuries lead to stricture formation. Although a number of agents have been tried experimentally to prevent strictures, few have gained clinical application. The purpose of this study was to investigate the effectiveness of Mitomycin C (MMC), which inhibits fibroblastic proliferation in preventing caustic esophageal strictures. MATERIAL AND METHODS: Fifty-six rats were allocated into four groups. Caustic esophageal burns were created as described by Gehanno. Group A was instilled only with saline. Group B was injured and untreated. Groups C and D were injured and received topical MMC at 0.02 and 0.04% concentrations, respectively. At 28 days, stenosis index (SI), collagen deposition, and hydroxyproline content (HP) were determined in distal esophageal segments. Statistical analyses were done. RESULTS: Mean SI in Group B was significantly higher than others (P < 0.05). Mean SI was statistically higher in Group C than A and D and similar between groups A and D. The greatest accumulation of collagen was found in Group B, followed by Group C, D, and A, respectively. Collagen deposition in Group D was statistically lower than Group B (P < 0.01) and similar to Group C. Mean HP in Group B was statistically higher than others (P < 0.05), significantly higher in Group C than Group D (P = 0.047), and similar between Groups A and D (P = 0.73). CONCLUSION: MMC was effective in preventing strictures following experimental caustic esophageal injury, in a dose-dependent manner. We consider that it can gain clinical utilization with the establishment of effective mode, dose, and timing of therapy.  相似文献   
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