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排序方式: 共有314条查询结果,搜索用时 15 毫秒
71.
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OBJECTIVE: The authors set out to determine what general factors are important in the selection of a psychiatric residency program, the views applicants have of several aspects of the Johns Hopkins Hospital Psychiatric Residency Program, and what relationships exist among these elements. METHODS: A survey mailed to Johns Hopkins Hospital psychiatric residency-interviewed applicants asked applicants to rate six factors in relation to choosing a psychiatric residency program. A second section asked applicants to rate five factors more specific to the Johns Hopkins Hospital residency. RESULTS: The most important general factors in choosing a residency program included the perceived philosophical orientation of a psychiatric department, exposure to different psychotherapy modalities, and the perceived prestige of the department. Several statistically significant correlations were evident among factors. CONCLUSION: Knowledge of applicants' views could assist residency program directors in their assessment of factors influencing program choices. 相似文献
73.
Coronary artery bypass grafting (CABG) in patients with severe pectus excavatum is a surgical challenge. A two-stage correction of sternal deformities and cardiac lesions has been described and myocardial revascularization through a left lateral thoracotomy is a valid alternative in urgent situations. We report a one-stage repair of severe pectus excavatum and CABG with the use of bilateral internal thoracic arteries in a young patient requiring urgent myocardial revascularization. The technical aspects and operative consideration are discussed. 相似文献
74.
Dimitry A. Chistiakov Veronika A. Myasoedova Victor V. Revin Alexander N. Orekhov Yuri V. Bobryshev 《Experimental and molecular pathology》2017,102(1):138-145
Studies in non-rodent and murine models showed that atherosclerosis can be reversed. Atherosclerosis progression induced by high-fat or cholesterol-rich diet can be reduced and reversed to plaque regression after switching to a normal diet or through administration of lipid-lowering agents. The similar process should exist in humans after implementation of lipid-lowering therapy and as a result of targeting of small rupture-prone plaques that are major contributors for acute atherosclerotic complications. Lowering of low density lipoprotein (LDL) cholesterol and the activation of reverse cholesterol transport lead to a decline in foam cell content, to the depletion of plaque lipid reservoirs, a decrease in lesional macrophage numbers through the activation of macrophage emigration and, probably, apoptosis, dampening plaque inflammation, and the induction of anti-inflammatory macrophages involved in clearance of the necrotic core and plaque healing. By contrast, plaque regression is characterized by opposite events, leading to the retention of atherogenic LDL and oxidized LDL particles in the plaque, an increased flux of monocytes, the immobilization of macrophages in the intimal vascular tissues, and the propagation of intraplaque inflammation. Transfer of various apolipoprotein (apo) genes to spontaneously hypercholesterolemic mice deficient for either apoE or LDL receptor and, especially, the implementation of the transplantation murine model allowed studying molecular mechanisms of atherosclerotic regression, associated with the depletion of atherogenic lipids in the plaque, egress of macrophages and phenotypic switch of macrophages from the proinflammatory M1 to the anti-inflammatory M2. 相似文献
75.
Dimitry A. Chistiakov Tatiana P. Shkurat Alexandra A. Melnichenko Andrey V. Grechko 《Annals of medicine》2018,50(2):121-127
Cardiovascular disease (CVD) is a leading cause of mortality worldwide. Proper mitochondrial function is necessary in tissues and organs that are of high energy demand, including the heart. Mitochondria are very sensitive to nutrient and oxygen supply and undergo metabolic adaptation to the changing environment. In CVD, such an adaptation is impaired, which, in turn, leads to a progressive decline of the mitochondrial function associated with abnormalities in the respiratory chain and ATP synthesis, increased oxidative stress, and loss of the structural integrity of mitochondria. Uncoupling of the electron transport chain in dysfunctional mitochondria results in enhanced production of reactive oxygen species, depletion of cell ATP pool, extensive cell damage, and apoptosis of cardiomyocytes. Mitophagy is a process, during which cells clear themselves from dysfunctional and damaged mitochondria using autophagic mechanism. Deregulation of this process in the failing heart, accumulation of dysfunctional mitochondria makes the situation even more adverse. In cardiac pathology, aberrations of the activity of the respiratory chain and ATP production may be considered as a core of mitochondrial dysfunction. Indeed, therapeutic restoration of these key functional properties can be considered as a primary goal for improvement of mitochondrial dysfunction in CVD.
- Key messages
Mitochondrial dysfunction plays a crucial role in cardiovascular disease pathogenesis.
Cardiovascular disease is associated with altered mithochondrial biogenesis and clearance.
In cardiovascular disease, impaired mitochondrial function results in decreased ATP production and enhanced ROS formation.
76.
Krupitsky EM Neznanova O Masalov D Burakov AM Didenko T Romanova T Tsoy M Bespalov A Slavina TY Grinenko AA Petrakis IL Pittman B Gueorguieva R Zvartau EE Krystal JH 《The American journal of psychiatry》2007,164(3):519-523
OBJECTIVE: Ethanol blocks N-methyl-d-aspartic acid (NMDA) glutamate receptors. Increased NMDA receptor function may contribute to motivational disturbances that contribute to alcoholism. The authors assessed whether the NMDA receptor antagonist memantine reduces cue-induced alcohol craving and produces ethanol-like subjective effects. METHOD: Thirty-eight alcohol-dependent inpatients participated in three daylong testing sessions in a randomized order under double-blind conditions. On each test day, subjects received 20 mg of memantine, 40 mg of memantine, or placebo, and subjective responses to treatment were assessed. The level of alcohol craving was assessed before and after exposure to an alcohol cue. RESULTS: Memantine did not stimulate alcohol craving before exposure to an alcohol cue, and it attenuated alcohol cue-induced craving in a dose-related fashion. It produced dose-related ethanol-like effects without adverse cognitive or behavioral effects. CONCLUSIONS: These data support further exploration of whether well-tolerated NMDA receptor antagonists might have a role in the treatment of alcoholism. 相似文献
77.
78.
Bruder D Nussbaum AK Gakamsky DM Schirle M Stevanovic S Singh-Jasuja H Darji A Chakraborty T Schild H Pecht I Weiss S 《International immunology》2006,18(1):89-100
Immunodominance in CD8+ T cell responses against Listeria monocytogenes is a well-recognized but still not fully understood phenomenon. From listeriolysin, the major virulence factor of L. monocytogenes, only a single epitope, pLLO91-99, is presented by MHC class I molecules in BALB/c mice which dominates the cytotoxic T cell response against this bacterial pathogen. To obtain more insights into the molecular and cellular mechanisms underlying immunodominance of this particular epitope, we compared the various steps involved in the presentation and recognition of pLLO91-99 derived from a wild-type toxin with an equivalent epitope from a mutated toxin. This fully functional variant contains within the pLLO91-99 epitope a conservative isoleucine to alanine replacement at the C-terminal anchor residue which results in loss of antigenicity. The binding properties of the variant peptide to soluble Kd remained unaffected and cytotoxic T cells capable of recognizing the pLLO99A/Kd complex were detectable in BALB/c mice. However, such T cells required higher concentrations of antigen in order to be optimally activated in vitro. A comparison between the TAP translocation efficiency of wild-type and mutant peptide demonstrated that the mutation at the C-terminus leads to a reduced transportation rate. Furthermore, the amino acid substitution changes the in vitro proteasomal cleavage pattern, resulting in a reduced liberation of the correct peptide from a polypeptide precursor. Thus, in all assays employed the immunodominant epitope performs optimally while the variant was found to be inferior. The synergy of all these steps most likely is the decisive factor in the immunodominance of pLLO91-99. 相似文献
79.
Stefanich EG Ren S Danilenko DM Lim A Song A Iyer S Fielder PJ 《The Journal of pharmacology and experimental therapeutics》2008,327(2):308-315
B cell-activating factor receptor 3 (BR3)-Fc is an IgG1-receptor dimeric fusion protein that has multiple O-linked glycosylation sites and sialylation levels that can vary in the manufacturing process. Increased sialic acid levels resulted from increased site occupancy with the O-linked N-acetylgalactosamine (GalNAc-Gal), but because the ratio of sialic acid per mole of oligosaccharide remained approximately 1, this led to increased asialo terminal GalNAc. Previous studies have demonstrated an effect of terminal asialo Gal or GalNAc on the clearance of glycoproteins due to uptake and degradation by lectin receptors in the liver. However, the previous studies examined N-linked oligosaccharides, and there are less data regarding O-linked oligosaccharides. The objective of these studies was to determine the effects on the pharmacokinetics and distribution of the asialo terminal GalNAc and varying amounts of sialic acid residues on BR3-Fc. The results of the data presented here suggest that exposed Gal on the desialylated BR3-Fc led to rapid clearance due to uptake and degradation in the liver that was associated with nonparenchymal cells. It is interesting to note that the data indicated a decreased clearance and increased exposure of BR3-Fc as the sialic acid levels increased, even though increased sialic acid was associated with increased asialo GalNAc. Therefore, the exposed GalNAc did not seem to play a role in the clearance of BR3-Fc; although the Gal linked to the hydroxyl group at position 3 may have prevented an interaction. Because we did not see uptake of desialylated BR3-Fc in hepatocytes where the asialoglycoprotein receptor is localized, this nonparenchymal cell lectin may have preference for O-linked glycoproteins. 相似文献
80.