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91.
Ten 5-nitro-2-furyl derivatives, with good to excellent in vitro anti-Trypanosoma cruzi activity, and nifurtimox were tested oral and intraperitoneally on healthy animals for its acute toxicity on murine models. According to animals' survival percentage, organ histological results, biochemical and haematological findings, three new derivatives, with toxicity like nifurtimox, were selected to test in vivo as antichagasic agents. Clearly, dependences between chemical structure and both acute toxicity and in vivo anti-T. cruzi activity were observed. 4-Hexyl-1-[3-(5-nitro-2-furyl)-2-propenylidene]semicarbazide displayed good profile as anti-T. cruzi agent and better acute toxicity profile than nifurtimox.  相似文献   
92.
This paper discusses the results of the research work on medical technology in several countries by research teams whose goals are to prompt the exchange of information and support practical cooperation. Emphasis is placed on the work developed by the Pan American Health Organization, which has supported 45 research proposals on medical technology and stimulated the association of academic groups, national institutions and international agencies. The authors also describe the research activities of the team devoted to medical technology research at the National Institute of Public Health in Mexico.  相似文献   
93.
Kainic acid‐induced (KA) hippocampal damage leads to neuronal death and further synaptic plasticity. Formation of aberrant as well as of functional connections after such procedure has been documented. However, the impact of such structural plasticity on cell activation along time after damage and in face of a behavioral demand has not been explored. We evaluated if the mRNA and protein levels of plasticity‐related protein synaptophysin (Syp and SYP, respectively) and activity‐regulated cytoskeleton‐associated protein mRNA and protein levels (Arc and Arc, respectively) in the dentate gyrus were differentially modulated in time in response to a spatial‐exploratory task after KA‐induced hippocampal damage. In addition, we analyzed Arc+/NeuN+ immunopositive cells in the different experimental conditions. We infused KA intrahippocampally to young‐adult rats and 10 or 30 days post‐lesion (dpl) animals performed a hippocampus‐activating spatial‐exploratory task. Our results show that Syp mRNA levels significantly increase at 10dpl and return to control levels after 30dpl, whereas SYP protein levels are diminished at 10dpl, but significantly increase at 30dpl, as compared to 10dpl. Arc mRNA and protein levels are both increased at 30dpl as compared to sham. Also the number of NeuN+/Arc+ cells significantly increases at 30dpl in the group with a spatial‐exploratory demand. These results provide information on the long‐term modifications associated to structural plasticity and neuronal activation in the dentate gyrus after excitotoxic damage and in face of a spatial‐exploratory behavior. Anat Rec, 300:425–432, 2017. © 2016 Wiley Periodicals, Inc.  相似文献   
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BackgroundIt is not clear whether patients with some degree of immunosuppression have worse outcomes in SARS-CoV-2 infection, compared to healthy people.ObjectiveTo carry out a narrative review of the information available on infection by SARS-CoV-2 in immunosuppressed patients, especially patients with cancer, transplanted, neurological diseases, primary and secondary immunodeficiencies.ResultsPatients with cancer and recent cancer treatment (chemotherapy or surgery) and SARS-CoV-2 infection have a higher risk of worse outcomes. In transplant patients (renal, cardiac and hepatic), with neurological pathologies (multiple sclerosis [MS], neuromyelitis optica [NMODS], myasthenia gravis [MG]), primary immunodeficiencies and infection with human immunodeficiency virus (HIV) in association with immunosuppressants, studies have shown no tendency for worse outcomes.ConclusionGiven the little evidence we have so far, the behaviour of SARS-CoV-2 infection in immunosuppressed patients is unclear, but current studies have not shown worse outcomes, except for patients with cancer.  相似文献   
96.
The aim of this study is to determine the effect of proteins from cereals and legumes on heme iron (Fe) absorption. The absorption of heme Fe without its native globin was measured. Thirty adult females participated in two experimental studies (15 per study). Study I focused on the effects of cereal proteins (zein, gliadin and glutelin) and study II on the effects of legume proteins (soy, pea and lentil) on heme Fe absorption. When heme was given alone (as a control), study I and II yielded 6.2% and 11.0% heme absorption (p > 0.05). In study I, heme Fe absorption was 7.2%, 7.5% and 5.9% when zein, gliadin and glutelin were added, respectively. From this, it was concluded that cereal proteins did not affect heme Fe absorption. In study II, heme Fe absorption was 7.3%, 8.1% and 9.1% with the addition of soy, pea and lentil proteins, respectively. Only soy proteins decreased heme Fe absorption (p < 0.05). These results suggest that with the exception of soy proteins, which decreased absorption, proteins derived from cereals and legumes do not affect heme Fe absorption.  相似文献   
97.
Previous studies have shown an association between substance use in the corrections population and, though the overall probation population has been declining, the percentage of women on probation has significantly increased. This study collected data on the factors associated with substance use and criminality among West Texas women who were sentenced to the U.S. Probation and Pretrial Services System (USPPSS). Intake records for USPPSS adult women spanning 3 years were reviewed. Among all age distributions and demographics, alcohol use was found to be prevalent. A significant positive correlation was found between immediate and extended family use of alcohol or drugs. Approximately one third of women reported a lifetime history of psychiatric treatment and three fourths reported a lifetime history of emotional/verbal, physical, and/or sexual abuse. The significant association with alcohol and substance use among these women should be addressed when determining probation planning and social services. Furthermore, the high incidence of emotional/verbal, physical and/or sexual abuse, and suicidality in this population would recommend an approach that includes provision of adequate mental health services.  相似文献   
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Recent research has demonstrated that mucocutaneous epithelial cells express functional nicotinic acetylcholine receptors (nAChRs) and that tobacco-derived carcinogenic nitrosamines, such as 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), and SLURP (secreted mammalian Ly-6/urokinase plasminogen activator receptor-related protein)-1 and -2 can act as non-canonical ligands of these receptors. It was found that recombinant SLURP-1 and -2 can lessen tumorigenic activity of nitrosamines. The immortalized esophageal keratinocytes (Het-1A cells) exhibit low SLURP-1 and -2 mRNA levels that decrease further after treatment with NNK. Based on these observations, we hypothesized that overexpression of full length SLURP proteins may protect Het-1A cells from malignant transformation by NNK. The Het-1A cells transfected with either SLURP-1 or -2 vector produced the highest amounts of respective proteins between 24 and 48 h, at which point they were exposed to 1 microM NNK for 24 h and their tumorigenic activities were subsequently evaluated by plating in soft agar and injecting subcutaneously to Nu/Nu mice. Transfection with either SLURP-1 or -2 cDNA in both cases significantly (p<0.05) diminished the number of colonies produced by NNK exposed cells. SLURP-1 was more efficient than SLURP-2 in abolishing the tumorigenic effect in nude mice. Thus, the anti-tumorigenic activities of SLURP-1 and -2 were demonstrated both in vitro and in vivo. The obtained results suggest that SLURP-like proteins may become useful for developing novel anti-cancer therapies.  相似文献   
100.
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