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81.
This work studied antinociceptive, antiedematogenic and central depressor effects of the hydroalcoholic extract (HAE) from Aeolanthus suaveolens and its fractions: hexane (ASHAE-H), ethyl acetate (ASHAE-A), aqueous (ASHAE-E) and precipitate (ASHAE-PPT) in experimental models in mice. The highest activity in the writhing test was presented by ASHAE-A followed by ASHAE-PPT and ASHAE-E and the lowest by ASHAE-H. In the formalin test the effect was manifested at both phases, although more intensely at the 2nd phase of the response. In this test, the most active fraction was ASHAE-PPT causing inhibitions of the order of 76 and 90% of the 2nd phase of the test at the doses of 10 and 100 mg/kg i.p., respectively. Naloxone reversed the effects of ASHAE-PPT in both phases of the test, suggesting the participation of the opioid system in the antinociceptive effect. On the other hand, the HAE effect on both phases of the formalin test was only partially reversed by naloxone, suggesting that the extract presents more than one active compound, and at least one, of a polar nature, acting through the opioid system. HAE and ASHAE-PPT presented antiinflammatory activity and were very effective in decreasing the mouse paw edema induced by carrageenan. All fractions significantly decreased locomotor activity in the open field test in mice. However, only the nonpolar fractions presented myorelaxant activity as demonstrated by the rota rod test.  相似文献   
82.
Rationale There is a large body of evidence indicating that the mesoaccumbens dopamine pathway is critically involved in the expression of behavioral sensitization to amphetamine and cocaine, but its role in the development of sensitization to psychostimulants is not that sound. Very few studies, however, have examined the role of dopamine transmission in 3,4-methylenedioxymethamphetamine (MDMA)-induced sensitization.Objectives The effects of the D1 receptor antagonist SCH 23390 on the development and expression of MDMA-induced behavioral sensitization were investigated in rats.Methods During the development phase of sensitization, SCH 23390 was administered 15 min before every administration of MDMA. After 12 days of withdrawal, a MDMA challenge dose was given and locomotor activity was measured. In separate experiments, 15 min before the challenge injection of MDMA, SCH 23390 was administered either systemically or directly into the core of the nucleus accumbens (NAc) of MDMA-pretreated rats.Results SCH 23390 did not prevent the development of MDMA-induced behavioral sensitization but completely blocked the expression when given before the challenge dose of MDMA. The same results were obtained when SCH 23390 was locally applied into the core of the NAc.Conclusions The present data suggest that D1 receptor stimulation is not critical for the development of long-term MDMA sensitization, in agreement with what has been reported for cocaine. By contrast, expression of sensitization depends on the activation of D1 receptors located in the NAc core.  相似文献   
83.
A series of seven cases are presented in which intravenous vitamin C has been used as antineoplastic agent in the treatment of different types of cancers. The cancers cases reviewed are the following: Renal cell carcinoma (2), Colorectal cancer (1), Pancreatic cancer (1), Non-Hodgkin's lymphoma (2) and breast cancer (1). Toxic reactions were not observed at these high doses of intravenous Vitamin C. All patients were prescreened for Glucose 6--phosphate dehydrogenase deficiency before administering intravenous Vitamin C in order to prevent hemolysis.  相似文献   
84.
85.
The recombinant histidine-rich protein II (HRPII) from Plasmodium falciparum was shown to bind actin and phosphatidylinositol 4,5-bisphosphate (PIP(2)) in vitro in a pH-dependent manner, very similar to hisactophilin, an actin-binding protein from ameba. Binding of HRPII to actin and PIP(2) occurred at pH 6.0 and 6.5, but not above pH 7.0. Circular dichroism (CD) spectroscopy confirmed that HRPII interacts with actin at pH below 7.0, as judged by the changes induced in the secondary structure of the HRPII/actin mixture. Further CD analysis demonstrated that HRPII adopts a predominantly alpha-helical conformation with anionic micelles of PIP(2) and SDS, but not with neutral micelles of phosphatidylcholine (PC), a feature that is common to many actin-binding proteins involved in cytoskeleton remodeling. Similarly to hisactophilin, a GFP-HRPII fusion protein shuttled from the cytoplasm to the nucleus of HeLa cells as the cellular pH was lowered from 8.0 to 6.0. HeLa cells transfected with the HRPII gene showed increased levels of histidine-rich proteins (HRPs) in the soluble cell fraction at pH 8.0. At pH 6.0, however, HRPs were detected mainly in the insoluble cell fraction. Interestingly, we found that HRPII binds to human erythrocyte membranes at pH 6.0 and 6.5 but not at pH above 7.0. Our results point to remarkable similarities between HRPII, hisactophilin, and actin-binding proteins. Possible roles of the HRPII during Plasmodium infection are discussed in the light of these findings.  相似文献   
86.
Adenovirus Ascending Cholangiohepatitis   总被引:1,自引:0,他引:1  
Three children, two with liver transplants and one with acquired human immunodeficiency virus (HIV) infection, presented with hepatitis accompanied by elevated gamma glutamyl transpeptidase. Biopsies revealed cholangiohepatitis caused by adenovirus infection. There was a progressive loss of interlobular bile ducts in two of the patients. In one patient, infection of the biliary tree was marked by a necrotizing cholangitis, with adenoviral inclusions noted in the biliary epithelium. In each patient, there was evidence of adenovirus gastrointestinal infection. This is the first report of adenoviral infection of the biliary tree in humans. It is hypothesized that adenovirus cholangiohepatitis occurs as a result of ascending infection from the gastrointestinal tract to the biliary tree.  相似文献   
87.
88.
Andaluz N  Tew JM 《Neurosurgery》2003,53(2):432-5; discussion 435
OBJECTIVE AND IMPORTANCE: We present a rare case of an intradural aneurysm that arose from the posterior genu of the cavernous carotid artery and was diagnosed via angiography as originating from the internal carotid artery (ICA) at the level of the posterior communicating artery. Our review of the English-language literature found no other case of an intradural aneurysm that originated at the posterior genu of the cavernous ICA. CLINICAL PRESENTATION: A 65-year-old woman presented with increasingly severe left retro-orbital headaches. Her family history included aneurysmal subarachnoid hemorrhage. Angiography revealed an 11-mm aneurysm, which was interpreted as arising from the left ICA at the level of the posterior communicating artery. INTERVENTION: During a left pterional craniotomy, an aneurysm was identified underneath the oculomotor nerve; its neck seemed to arise from the posterior communicating artery segment. Despite clipping of the aneurysm attachment to the ICA and trapping of the posterior communicating segment, the aneurysm continued to fill. Further dissection revealed that the aneurysm's neck originated from the cavernous ICA. Placement of fenestrated clips around the oculomotor nerve successfully occluded the intradural portion of the aneurysm, as documented by an intraoperative angiogram. CONCLUSION: We discuss this unique case to draw attention to the importance of the interpretation and adequacy of preoperative angiography, and we review pertinent vascular anatomy.  相似文献   
89.
Hepatic uptake and biliary excretion of bile salts and non-bile salt organic anions is mediated by specific transport proteins located at the basolateral and canalicular membranes of hepatocytes. Several hepatobiliary transport systems have been identified and cloned over the past years. This development has facilitated molecular biological and genetic analyses of these transporters in experimental cholestasis and human cholestatic liver diseases. Evidence now exists that decreased or even absent expression of hepatobiliary transport systems may explain impaired transport function resulting in hyperbilirubinemia and cholestasis. This review summarizes the molecular defects in hepatocellular membrane transporters associated with hereditary and acquired forms of cholestatic liver diseases. The increasing information on the molecular regulation of hepatobiliary transport systems should bring new insights into the pathophysiology and treatment of human cholestatic liver diseases.  相似文献   
90.
High dose intravenous(i.v.) ascorbic acid (AA) has been used as therapy for infectious disease from bacterial and viral origin and adjuvant therapy for cancer. In this publication we describe a clinical protocol that has been developed over the past twenty years utilizing high dose i.v. AA as therapy for cancer. This includes principles of treatment, rationale, baseline workup, infusion protocol, precautions and side effects.  相似文献   
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