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51.
应用标准微电极技术,研究了关附甲素对豚鼠右心室乳头肌动作电位最大除极速率(Vmax)的频率依赖性抑制作用(RDB),并与美西律,奎尼丁,劳卡尼进行了比较. 在相同刺激间隔(300 ms),产生50%左右RDB的药物浓度下,美西律的RDB开始最快,其第2个Vmax所产生的抑制已占RDB的64%,奎尼丁,劳卡尼和关附甲素的RDB开始速率常数分别为每个动作电位0.165, 0.076和0.136. 美西律,奎尼丁,劳卡尼和关附甲素产生RDB的恢复时间常数分别为1.4, 9.0, 18.2和44.0 s,而且它们的恢复时间常数是不依赖于药物浓度而变化的,结果提示,关附甲素是一个慢动力学钠通道阻滞剂. 相似文献
52.
Creating empowering meaning: an interactive process of promoting health with chronically ill older Canadians 总被引:2,自引:1,他引:1
McWilliam C; Stewart M; Brown J; McNair S; Desai K; Patterson M; Del Maestro N; Pittman B 《Health promotion international》1997,12(2):111-123
Many health promotion approaches afford education about disease prevention
and enhancement of one's health status. But strategies for enabling older
people with chronic illness to better mobilize their resources for everyday
living still require development. This practical action research study
explored the experiences of 13 purposefully selected older persons who
participated in a health promotion intervention premised on the adult
education theory of perspective transformation. Findings illuminate health
promotion through a holistic interactive process in which professional and
chronically ill older person together evolved a caring relationship and
enhanced conscious awareness of life and health experiences. Five
health-promoting strategies were identified: building trust and meaning;
connecting; caring; mutual knowing; and mutual creating. Researchers
suggest several important directions to refine professional practice
approaches and health care delivery systems in order to promote the health
of older persons with chronic conditions. 相似文献
53.
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55.
The relationship between bladder cancer and occupational exposure to asbestos was investigated between 1978 and 1982 at La Paz Hospital in Madrid in a case-control study conducted among 353 male patients and 53 women with a diagnosis of urothelium carcinoma, and among an equal number of controls matched in age (decade of life), sex and date of admission to the hospital. The results showed that bladder cancer is associated with occupational exposure to asbestos. 相似文献
56.
Maria P. Panozzo Carlo Fabris Daniela Basso Giuseppe Del Favero Aldo Infantino Attilio Cecchetto Mario Plebani Remo Naccarato 《Clinical and experimental pharmacology & physiology》1993,20(3):185-191
1. The authors investigated the effect of two extrahepatic cholestasis models (one by bile duct ligation and the other by choledocho-jugular fistula) on the hepatic clearance of horseradish peroxidase in male Sprague-Dawley rats divided into four groups. 2. In groups A (n = 5 rats) and B (n = 5), bile duct ligation was performed, while a choledocho-jugular fistula was created in groups C (n = 5) and D (n= 7). A 10 mg intravenous bolus of horseradish peroxidase was injected after 24 h (groups A and C), 48 h (groups B and D) or 1 h (Group E; five sham-operated rats). Serum and bile samples were then serially collected for 2 h. 3. In all groups, serum horseradish peroxidase levels increased soon after injection and then rapidly decreased, the curves being similar. Biliary excretion increased for 30 min and then slowly decreased. The highest horseradish peroxidase biliary concentrations and outputs were found in Group B followed by Group A; both groups had significantly higher levels than Group E. No difference was found between horseradish peroxidase biliary excretion of groups C and D and that of sham-operated rats. 4. When each group was considered separately, sampling times correlated with the corresponding ratios of bile/ plasma HRP. Significant differences were found between the relative slopes of groups A, B and E, but not between those of groups C, D and E. 5. In conclusion, bile duct obstruction greatly affects the plasma-bile transfer of fluid phase markers, such as horseradish peroxidase, while single retention, caused by choledocho-jugular fistula, has no influence. The increased biliary hyperpressure related to the duration of cholestasis may account for the degree of horseradish peroxidase transfer which, in turn, probably depends on an enhanced paracellular passage. 相似文献
57.
Marc Ziegler Alexandre Castro-Caldas Susanna Del Signore Olivier Rascol 《Movement disorders》2003,18(4):418-425
Piribedil is a non-ergot D2/D3 agonist with a significant antagonist action on alpha2A and alpha2C adrenergic receptor subtypes. This double-blind placebo-controlled study was undertaken to confirm the efficacy of 150 mg/day piribedil po in improving motor symptoms of idiopathic Parkinson's disease (PD) in nonfluctuating patients insufficiently controlled by a stable daily dose of levodopa (L-dopa). Efficacy was assessed using the Unified Parkinson's Disease Rating Scale (UPDRS) III score as primary criterion over 4 months. A second comparison was planned at 6 months, after possible adjustment of L-dopa. At 4 months, the rate of response, defined as a 30% decrease from baseline on UPDRS III score, was significantly greater with piribedil compared with placebo (56.4% vs. 37.7%; P = 0.040). At 6 months, the better efficacy of piribedil was maintained (61.8% of responders vs. 39.6% on placebo; P = 0.020). The difference between groups on UPDRS III change from baseline reached statistical significance only at 6 months: -10.0 points in the piribedil group vs. -6.7 points in the placebo group (P = 0.037). Secondary end-points were not significantly different. The most frequently reported adverse events were gastrointestinal symptoms (27 of 61 patients in the piribedil group vs. 13 of 54 patients in the placebo group). In conclusion, a 6-month oral administration of 150 mg/day piribedil in combination with L-dopa is well tolerated, except for minor gastrointestinal symptoms at the beginning of the treatment and significantly improves motor symptoms compared with placebo in PD nonfluctuating patients. 相似文献
58.
Evidence for the presence of substance P-like immunoreactivity in the human cerebellum 总被引:1,自引:0,他引:1
M. Del Fiacco M. T. Perra M. Quartu M. D. Rosa G. Zucca M. C. Levanti 《Brain research》1988,446(1):173-177
Preliminary results on the localization of substance P-like immunoreactivity in the human cerebellum are presented. Cerebella from newborn and adult subjects were examined. While only sporadic positive fibres were detected in the adult tissue, the immunoreactive material appeared more abundant in the cerebella from newborn subjects. Varicose and non-varicose fibres and dot-like nerve terminals were present with different density in various regions. The paucity of immunoreactive perikarya suggests that most of the cerebellar substance P-like immunoreactive material has an extrinsic origin. 相似文献
59.
Hand-assisted laparoscopic nephroureterectomy for upper urinary tract transitional cell carcinoma. 总被引:1,自引:0,他引:1
Jay D Raman Michael A Palese Casey K Ng Stephen A Boorjian Douglas S Scherr Joseph J Del Pizzo R Ernest Sosa 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2006,10(4):432-438
OBJECTIVE: We report our experience with hand-assisted laparoscopic nephroureterectomy (HALN) for upper urinary tract transitional cell carcinoma and compare our results with a contemporary series of open nephroureterectomy (ON) performed at our institution. METHODS: Between August 1996 and May 2003, 90 patients underwent nephroureterectomy for upper-tract transitional cell carcinoma (TCC). Thirty-eight patients underwent HALN, while 52 had an ON. End-points of comparison included operative time, estimated blood loss (EBL), intraoperative and postoperative complications, length of hospital stay, pathologic grade and stage of tumor, and tumor recurrence. RESULTS: The mean patient age was 72.3 and 70.6 years in the ON and HALN groups, respectively. Mean operative duration was 243 minutes (ON) and 244 minutes (HALN), with an EBL of 478mL in the open group versus 191 mL in the hand-assisted group (P<0.001). No intraoperative complications occurred, but postoperative complications occurred in 4% and 11% of the ON and HALN groups, respectively (P=0.21). The mean hospital duration was 7.1 days (ON) versus 4.6 days (HALN) (P<0.01). No difference existed in the pathologic grade or stage distribution of urothelial tumors between the 2 groups. The mean follow-up was 51.0 months in the ON group and 31.7 months in the HALN group. Recurrence of urothelial carcinoma occurred in 50% of patients who underwent ON and 40% treated by HALN (P=0.38) at a median interval of 9.1 and 7.7 months, respectively, after surgery. CONCLUSION: Hand-assisted laparoscopic nephroureterectomy is an effective modality for the treatment of upper urinary tract urothelial carcinoma. Patients benefited from less intraoperative blood loss and a shorter hospitalization with an equivalent intermediate-term oncologic outcome compared with that of the open approach. 相似文献
60.
抑郁障碍患者人格特征与发病关系的研究 总被引:7,自引:3,他引:4
目的探讨抑郁障碍患者的人格特征与其疾病发病间的关系。方法采用自评抑郁量表(SDS)、艾森克人格问卷 (EPQ)、应对方式评定量表 (WCRS)和归因方式问卷 (ASQ)对 76名抑郁障碍患者进行测试 ,同时选取 84名健康被试进行对照研究。结果①抑郁组患者在EPQ中神经质 (N)与精神质 (P)的得分显著高于健康组。②WCRS的结果显示在“宣泄接纳”、“退避调节”两个因子上 ,抑郁组的平均得分低于健康组。③在ASQ的得分中 ,抑郁组在负性事件归因的自身性、持久性和整体性均显著高于健康组。④抑郁障碍患者的“神经质”人格特质与应对方式的“宣泄接纳”和“退避调节”因子呈负相关 (r = 0 .474)。结论抑郁障碍患者的人格特征可表现为较强的神经质及孤僻、交往障碍 ,他们这种人格特征及应对和归因方式在其发病过程中起着重要作用。 相似文献