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921.
The present study was designed to determine whether the environmental context in which amphetamine is administered plays a role in the development of sensitization to the stereotyped behavioral effects of amphetamine in mice. In male CF-1 mice, the dose-response curve for stereotyped behavior elicited by amphetamine was shifted 1.9-fold to the left 48 h after pretreatment with 14 mg/kg amphetamine. Behavioral sensitization only developed in mice that were pretreated in the same or a similar environment as that of the test environment. In addition, when mice were placed in an environment that attenuated the acute expression of stereotyped behavior elicited by the pretreatment dose of amphetamine, sensitization never developed. A further experiment showed that 96% of the mice that expressed stereotypy after the ED50 pretreatment dose of 10 mg/kg amphetamine showed a stereotyped behavioral response to the lesser dose of 7 mg/kg 48 h later, indicating sensitization. In contrast, mice that did not express stereotypy after the ED50 dose of amphetamine failed to show a significant stereotyped behavioral response to amphetamine challenge compared to vehicle-pretreated controls. Therefore, the results indicate that preexposure to a single high dose of amphetamine produces context- and response-dependent sensitization to amphetamine-induced stereotyped behavior.  相似文献   
922.
OBJECTIVE: The TWEAK is a screening instrument used to identify women who are risk drinkers. Potential limitations of previous studies of the TWEAK in the prenatal setting include indirect administration of the instrument to minority, indigent pregnant women. The purpose of this study is to assess the efficacy of the TWEAK when it is given directly to a sample of pregnant women of different socioeconomic backgrounds. METHOD: The original TWEAK, with two different tolerance questions, was administered to a sample of 135 pregnant women enrolled in a study of alcohol use during pregnancy at the obstetrics practices of the Brigham and Women's Hospital in Boston, Massachusetts. RESULTS: The TWEAK, using the first tolerance question (number of drinks before feeling the first effects of alcohol) with the cut point set at more than two drinks, had the best predictive ability for lifetime alcohol diagnoses and risk drinking. The sensitivity of the TWEAK can be increased if the cut point for the first tolerance question is set at two drinks, with some loss of specificity and predictive ability. Medical record assessment was the least sensitive but most specific method of identifying alcohol use by pregnant women. CONCLUSIONS: The TWEAK has promise as a screening instrument for identifying risk drinking during pregnancy. Future work should include testing in other clinical populations.  相似文献   
923.
The causes of Datura intoxication include medication overdose, misuse of edible vegetables, deliberate abuse as a hallucinogen, homicidal or robbery and accidental intoxication from contaminated food. We report an incident of 14 people with Datura intoxication caused by ingesting wild Datura suaveolans for food. The incubation period was 15 to 30 min. The symptoms/signs were dizziness, dry mouth, flushed skin, palpitation, nausea, drowsiness, tachycardia, blurred vision, mydriasis, hyperthermia, disorientation, vomiting, agitation, delirium, urine retention, hypertension and coma. Three patients were hospitalized for 2-3 days. Thirteen persons received supportive fluid therapy. One patient did not receive medical therapy, he induced vomiting and drank a lot of water. Four patients presented with delirium/coma and 3 received physostigmine therapy with good response. One patient was intubated because of coma and respiratory depression. Three persons needed Foley catheterization for urine retention or coma status. One patient had a complication of urinary tract infection and antibiotic management. All patients recovered with no sequelae.  相似文献   
924.
Activity-guided fractionation of the roots of Anthriscus sylvestris resulted in the isolation and characterization of five cytotoxic compounds, deoxypodophyllotoxin (1), falcarindiol (2), and angeloyl podophyllotoxin (5) from the hexane soluble fraction and morelensin (3), bursehernin (4) from the chloroform soluble fraction. It is the first report of the occurrence of compound 5 in nature.  相似文献   
925.
Stereoselective synthesis of (+/-)-epibatidine analog 2, which contains the 8-azabicyclo[3.2.1]octane ring system, was achieved by using palladium-catalyzed Heck-type coupling reaction from 3.  相似文献   
926.
Cytotoxicities of four urushiols, congeners isolated from the sap of Korean lacquer tree (Rhus vernicifera Stokes), to 29 human cancer cell lines originated from 9 organs were evaluated. Their values of 50% growth inhibition were below 4 microg/ml, and showed cell line specific cytotoxicity. The present result is the first report on the cytotoxicity of urushiols suggesting that they would have an anticancer activity to human cancer cells.  相似文献   
927.
RP—HPLC测定清眩丸中欧前胡素的含量   总被引:6,自引:0,他引:6  
目的:建立反相高效液相色谱测定清眩丸中欧前胡素含量的方法。方法:采用乙醇做溶剂,水浴加热回流提取。LUNA-C18色谱柱分离测定,流动相为乙腈-水(53∶47),流速1mL·min-1,检测波长300nm。结果:欧前胡素与其相邻峰的分离度是15,理论板数按欧前胡素峰计算是16155,欧前胡素对照品线性范围是1462~4875μg·mL-1,加样平均回收率980%。结论:用本文方法测定清眩丸中欧前胡素的含量,操作简便,结果准确。  相似文献   
928.
In November, 1993,M.G., a 6 year and 11 month-old girl, was admitted at Hospital Infantil Joana de Gusm?o--Florianópolis, SC, Brazil--with post-parotitis myocarditis and congestive heart failure. Three days after admission it was evidenced, on an echocardiogram, a thrombus in the left ventricle apex which, despite of correct treatment, embolized to iliac and small mesenteric arteries. Epidemic parotitis (mumps) is very common, being endemic around the world. Complications are rare and myocarditis, one of them, is more common than diagnosed because of its poor and benign manifestations, generally transient abnormalities of cardiac rhythm and conduction. This case was astonishing because of its rare subsequent event, that is, the formation of a ventricular mural thrombus during an acute myocarditis.  相似文献   
929.
The contents of 10 minor and trace elements in histologically confirmed gastric adenocarcinomas and their corresponding normal gastric mucosal tissues obtained from 39 patients at the time of gastric resection were simultaneously determined by instrumental neutron activation analysis. Specimens were irradiated by reactor neutrons and subsequently subject to direct analysis using a high-resolution HPGe -spectrometer. Univariate analysis revealed that gastric cancer tissues had significantly higher concentrations of Fe, K, Mg, Na, Rb, Se, and Zn than normal gastric mucosal tissues. However, multivariate analysis found that Fe, K, and Se were independent elements that associated with gastric cancer. Upon further evaluation of their clinical significance, we found a high tissue K level was related to lymphatic duct metastasis. High Se tissue levels were linked to intestinal type adenocarcinoma. A positive correlation was found between high Fe levels and vascular involvement. These findings suggest that Fe and K are associated with gastric cancer progression. Se is involved in carcinogenesis of stomach in high-risk areas. The mechanisms that underlie the corresponding pathohistological features deserve further study.  相似文献   
930.
Comparative effects of the nitric oxide (NO) synthase inhibitors, N(omega)-L-nitro-L-arginine methyl ester, and N(omega)-L-nitro-L-arginine benzyl ester on baseline arterial tone and on vasodilator responses to acetylcholine, isoproterenol, prostaglandin E(1), histamine, and nitroglycerin were investigated in the isolated mesenteric vascular bed of the rat. Under constant-flow conditions, intra-arterial (IA) injections of acetylcholine (100 ng--1 &mgr;g), isoproterenol (100 ng--1 &mgr;g), prostaglandin E(1) (0.3--3 &mgr;g), histamine (300 ng--3 &mgr;g), and nitroglycerin (100 ng--1 &mgr;g) caused dose-related decreases in mesenteric arterial perfusion pressure and decreases in systemic arterial pressure. Following administration of the NO synthase inhibitors, N(omega)-L-nitro-L-arginine methyl ester or N(omega)-L-nitro-L-arginine benzyl ester, mesenteric vascular resistance, and systemic arterial pressure were increased and mesenteric vasodilator responses to acetylcholine were significantly decreased, whereas N(omega)-L-nitro-L-arginine methyl ester and N(omega)-nitro-L-arginine benzyl ester did not significantly decrease vasodilator responses to nitroglycerin, histamine, isoproterenol, or prostaglandin E(1). The inhibitory effects of N(omega)-L-nitro-L-arginine methyl ester and N(omega)-L-nitro-L-arginine benzyl ester on vasodilator responses to acetylcholine suggest that acetylcholine-induced vasodilation in the mesenteric circulation of the rat is dependent on the release of NO from the endothelium. The increase in mesenteric vascular resistance following administration of N(omega)-L-nitro-L-arginine methyl ester and N(omega)-L-nitro-L-arginine benzyl ester suggest that tonic production of NO by the endothelium serves to maintain the mesenteric vascular bed of the rat in a dilated state.  相似文献   
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