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91.
Acute and chronic effects of nornicotine on locomotor activity in rats: altered response to nicotine
L. P. Dwoskin Peter A. Crooks LiHong Teng Thomas A. Green Michael T. Bardo 《Psychopharmacology》1999,145(4):442-451
Rationale: Nicotine, a tobacco alkaloid, is known to be important in the acquisition and maintenance of tobacco smoking. Nornicotine,
an active nicotine metabolite, stimulates nicotinic receptors and may produce psychomotor effects similar to nicotine. Objective: The present study determined the effects of acute and repeated administration of nornicotine on locomotor activity and compared
its effects with those of nicotine. Methods: R(+)-Nornicotine (0.3–10 mg/kg), S(–)-nornicotine (0.3–10 mg/kg), S(–)-nicotine (0.1–1 mg/kg) or saline was administered s.c. to rats acutely or repeatedly (eight injections at 48-h intervals).
Activity was recorded for 50 min immediately after each injection. Results: S(–)-Nicotine produced transient hypoactivity, followed by dose-related hyperactivity. Repeated S(–)-nicotine administration resulted in tolerance to the hypoactivity and sensitization to the hyperactivity. Subsequent testing
following a saline injection revealed evidence of conditioned hyperactivity. Acute administration of 0.3 mg/kg or 1 mg/kg R(+)- or S(–)-nornicotine produced no effect. Transient hypoactivity was observed at 3 mg/kg and 10 mg/kg R(+)-nornicotine and at 10 mg/kg S(–)-nornicotine. However, rebound hyperactivity was not observed following acute administration of either nornicotine enantiomer,
suggesting that nornicotine-induced psychomotor effects differ qualitatively from those of S(–)-nicotine. Repeated R(+)-nornicotine resulted in tolerance to the transient hypoactivity, however hyperactivity was not observed. Repeated S(–)-nornicotine resulted in tolerance to the hypoactivity and the appearance of hyperactivity. Repeated administration of
either nornicotine enantiomer resulted in a dose-dependent alteration in response to a 1 mg/kg S(–)-nicotine challenge, suggesting some commonalities in the mechanism of action. Conclusion: Nornicotine likely contributes to the neuropharmacological effects of nicotine and tobacco use.
Received: 11 January 1999 / Final version: 25 March 1999 相似文献
92.
Doppler sonographic detection of reverse twin-twin transfusion after intrauterine death of the donor
We report a "stuck" twin, in which a reverse blood shunt from the recipient to the donor was detected by Doppler sonography after death of the donor. This acute reverse transfusion caused intrauterine fetal distress and severe neonatal anemia of the surviving recipient. We believe that acute hemodynamic change after death of one fetus, in addition to causing a derangement in coagulation, causes immediate danger or subsequent organ damage for the surviving co-twin. 相似文献
93.
From 1979 to 1984, 88 women with epithelial ovarian cancer were treated with surgery and chemotherapy, achieved a clinical complete response, and then had "second-look" exploratory laparotomy to assess the pathologic status of their disease. Persistent cancer was found in 50 (57%) patients: 34 of 50 (68%) had gross tumor, which was larger than 2 cm in 12 (24%) and smaller than 2 cm in 22 (44%), and 16 (32%) had microscopic disease. Salvage therapy was as follows for these patients: whole abdominal irradiation, 29 (58%); chemotherapy, 17 (34%); intraperitoneal chromic phosphate, 1 (2%); and no further therapy, 3 (6%). With a follow-up time of 4 to 8 years, 7 (14%) patients are alive without evidence of cancer, 7 (14%) are alive with disease, 35 (70%) are dead of disease, and 1 (2%) has died of treatment complications. At 5 years, the relapse-free rate was 18% and the survival rate was 25%. Seventy-two parameters of suspected prognostic significance and 64 potential sites of tumor involvement were correlated with survival in a univariate analysis. The factors favorably affecting survival included the following: lower grade; microscopic tumor versus gross disease at second-look laparotomy; removal of the uterus; removal of the omentum; pelvic and paraaortic lymph node biopsy; negative results of a right diaphragm biopsy; and radiation therapy at Stanford University Medical Center, Stanford, California. There was no survival advantage for whole abdomen irradiation compared with chemotherapy or for the patients who had their disease successfully debulked at second-look laparotomy. The above factors and others were evaluated by multivariate regression. The best model (P = 0.000004) for predicting survival included largest tumor mass (P = 0.0002), operative blood loss (P = 0.002), perioperative blood transfusion (P = 0.003), and grade (P = 0.004). The detection of persistent ovarian cancer by second-look exploratory laparotomy should identify a subgroup of patients whose conditions can be salvaged by a second-line therapy. Unfortunately, that subgroup is small (8%) and an effective salvage therapy remains to be identified. 相似文献
94.
目的比较肝动脉化疗栓塞术(THAE)后经皮瘤内注射无水乙醇(PEI)与单纯THAE治疗单个肝细胞癌的疗效。方法53例肝细胞癌随机分成A(26例)、B(27例)两组。A组单纯THAE治疗;B组THAE治疗后,在CT引导下行PEI治疗。结果THAE组肿瘤治疗的部分缓解率为26.7%,1、2、3年生存率分别为56.0%、30.0%、0.0%。THAE+PEI组肿瘤治疗的部分缓解率为55.5%(P<0.05),1、2、3年生存率分别为91.0%、57.0%、22.0%(P<0.05)。结论THAE+PEI较单纯THAE对单个肝细胞癌的治疗更安全有效。 相似文献
95.
复方左氧氟沙星滴眼液的研制及临床应用 总被引:5,自引:2,他引:5
目的 :研究复方左氧氟沙星滴眼液的制备及质量控制方法 ,并观察其临床疗效。方法 :以左氧氟沙星为主药配伍地塞米松磷酸钠 ,选择磷酸盐作为缓冲剂 ,依地酸二钠作为稳定剂 ,采用紫外分光光度法测定左氧氟沙星的含量。结果 :制剂稳定 ,左氧氟沙星在2~6μg/ml范围内线性关系良好 ;C=26 1780A—1 0838(r=0 9997) ;平均回收率为100 34 % ,RSD=0 44%(n=5)。结论 :制备工艺简单 ,质控方法可靠 ,疗效良好 相似文献
96.
Treatment of glomerulonephritis in the elderly 总被引:1,自引:0,他引:1
With the increasing use of renal biopsy in the elderly, glomerulonephritis is now known to be a common finding. Whereas membranous glomerulonephritis and minimal change disease are common in younger and older adults, primary amyloidosis and crescentic glomerulonephritis are more common in the elderly. Other glomerulonephritides such as focal segmental glomerulosclerosis or IgA nephropathy are very uncommon in the elderly. Because of the serious consequences of the nephrotic syndrome and acute and chronic renal failure in the elderly, aggressive treatment with immunosuppression should not be withheld. Caution should always be taken because of the presumed greater morbidity and mortality from such treatment in the elderly. 相似文献
97.
肾癌组织 DGFR及c-Fos的表达研究 总被引:1,自引:0,他引:1
目的探讨PDGFR及蛋白c-Fos的表达与肾细胞癌(CC)发生的关系.方法应用免疫组化SP法检测12例正常肾组织、14例癌旁肾组织、46例肾细胞癌组织中PDGFR和c-Fos蛋白的表达,并结合肾癌的分级、分期和随访结果进行分析.结果 PDGFR及c-Fos在RCC组织中的表达阳性率分别为73.91%及52.17%,明显高于正常组织及癌旁组织,有显著性差异.PDGFR在透明细胞癌中的表达阳性率明显高于颗粒细胞癌,有显著性差异.PDGFR及c-Fos在RCC组织血管中的表达明显增强.PDGFR的表达与RCC的分级相关.结论 PDGFR及c-Fos的过度表达与RCC的发生密切相关,并与肿瘤血管形成相关.PDGFR的表达与RCC的恶性程度相关. 相似文献
98.
Wenjun Yi Zhonghua Tang Zhulin Yang Meiying Yu Yunshan Li Ganneng Chen 《中国肿瘤临床(英文版)》2004,1(5):354-358
Objective To study the difference in expression of VEGF and bFGF and their receptors in young and postmenopausal women with breast cancer.
Methods Immunohistochemical methods (SABC) were used to study the expression of VEGF, FLK-1, bFGF and FLG on paraffin-embedded sections
from 40 cases of young and 30 cases of postmenopausal women with breast cancer, The relationship between axillary lymph node
metastasis and the expression of the growth factors and their receptors was studied.
Results The mean expression of VEGF and bFGF and the positive rate of axillary lymph nodes in the young group were higher than that
in the postmenopausal group (P< 0.01 or P< 0.05 ); the mean values of VEGF, bFGF, FLK-1 and FLG in cases of axillary lymph
node metastasis were higher in patients without axillary lymph node metastasis in each group (P< 0.05 orP< 0.01); there was a significant difference between the mean expression of VEGF, bFGF, FLK-1 and FLG in cases of stage 0 ∼II comparaed to cases of stage III∼IV (P< 0.05 or P< 0.01).
Conclusion The tumor vasculature is directly related to the high breast cancer aggressiveness in young women, a characteristic that might
be due to the high expression of VEGF and bFGF. 相似文献
99.
高强度体外聚焦超声热疗治疗局部晚期胰腺癌的多中心临床研究 总被引:11,自引:1,他引:11
目的:探讨临床单用HIFU治疗局部晚期胰腺癌(local advanced pancreatic carcinoma,APC)的可能性。方法:4个中心共41例患者入选进行非随机病例对照研究,其中HIFU组24例,单用HIFU治疗;对照组17例,接受HIFU及吉西他滨综合治疗。比较两组的疗效、治疗费用及安全性,采用Cox回归分析进一步确定吉西他滨化疗对生存期的影响。结果:HIFU组临床受益率、平均生存期与对照组相似,分别为66.7%比76.5%(P=10.740)和141.5天比176.5天(P=0.3510);而治疗费用较低,为20500元比51805元(P=0.000);安全性更高。Cox回归分析显示仅体力状态、HIFU次数及临床受益进入方程(P=0.000),化疗对生存期无影响。结论:单用HIFU治疗APC,其疗效等同于HIFU和吉西他滨的综合治疗,但较综合治疗经济、安全。推测可以单独应用HIFU治疗局部晚期胰腺癌.值得临床进一步验证。 相似文献
100.
四川省凉山地区静脉吸毒人群药物滥用及其行为特征调查 总被引:10,自引:1,他引:10
目的:了解四川省凉山地区静脉吸毒人群药物滥用及行为特征情况,为采取有针对性的戒毒干预措施预防艾滋病病毒的传播提供数据.方法:以社区为基础招募了379名静脉吸毒人员,调查其人口学特征,艾滋病病毒感染情况,药物滥用的种类、吸毒方式和频率,口吸和静脉吸毒时间,共用注射器具情况等.结果:静脉吸毒人群艾滋病病毒感染率为11.3%(43/379).379名被调查者全部为海洛因滥用者,其中247人(65.2%)单独使用过海洛因,297人(78.4%)混合注射过海洛因与安定,滥用过的其他药物有安定(8.2%)和鸦片(1.3%).300人(79.2%)每天静脉注射吸毒一次及以上;曾经共用注射器具静脉吸毒的为247人(65.2%),87人(35.2%)首次静脉注射吸毒即与他人共用注射器具;初次口吸吸毒和静脉注射吸毒的平均年龄分别为22.37岁和25.35岁,口吸吸毒和静脉注射吸毒的平均时间分别为6.41年和3.42年.结论:加强青少年、吸毒人员关于毒品危害和拒绝毒品的健康教育活动,以及开展美沙酮或丁丙诺啡口服治疗海洛因依赖者,降低静脉注射吸毒行为,控制艾滋病病毒的传播. 相似文献