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61.
Background: Deviant and health risk behaviors among young-adults are associated with many adverse outcomes. Objectives: This study aims to evaluate a broad variety of behaviors by gender differences and their contribution to predicting cannabis use in undergraduate students. Method: This research is based on a structured, self-reported anonymous questionnaire distributed to 1,432 young adult undergraduate students at an Israeli University, 533 males and 899 females (mean age 27.4; SD 6.01).

Results: The findings demonstrate a significant proportion of sampled young adults reported to be involved in deviant and health risk behaviors and that all risky behaviors were more frequently significant in males than in females. Among drivers 72% reported speeding, 60% reported failure to keep distance, 44% reported being involved at a car accident as a driver, 40% reported not stopping at a stop sign, and quarter reported driving after drinking alcohol. These findings also expand how certain risk behaviors contribute to predicting cannabis use. Conclusions: The relatively high prevalence of some of these risky behaviors among normative young adults suggests that risky behaviors are considered as normative behavior for this group, especially among man, and therefore, policymakers need to consider prevention and harm reduction interventions relevant to this risk group.  相似文献   

62.
Adrenergic activation of L-type Ca2+ and various K+ currents is a crucial mechanism of cardiac adaptation; however, it may carry a substantial proarrhythmic risk as well. The aim of the present work was to study the timing of activation of Ca2+ and K+ currents in isolated canine ventricular cells in response to exposure to isoproterenol (ISO). Whole cell configuration of the patch-clamp technique in either conventional voltage clamp or action potential voltage clamp modes were used to monitor I Ca, I Ks, and I Kr, while action potentials were recorded using sharp microelectrodes. ISO (10 nM) elevated the plateau potential and shortened action potential duration (APD) in subepicardial and mid-myocardial cells, which effects were associated with multifold enhancement of I Ca and I Ks and moderate stimulation of I Kr. The ISO-induced plateau shift and I Ca increase developed faster than the shortening of APD and stimulation of I Ks and I Kr. Blockade of β1-adrenoceptors (using 300 nM CGP-20712A) converted the ISO-induced shortening of APD to lengthening, decreased its latency, and reduced the plateau shift. In contrast, blockade of β2-adrenoceptors (by 50 nM ICI 118,551) augmented the APD-shortening effect and increased the latency of plateau shift without altering its magnitude. All effects of ISO were prevented by simultaneous blockade of both receptor types. Inhibition of phosphodiesterases decreased the differences observed in the turn on of the ISO-induced plateau shift and APD shortening. ISO-induced activation of I Ca is turned on faster than the stimulation of I Ks and I Kr in canine ventricular cells due to the involvement of different adrenergic pathways and compartmentalization.  相似文献   
63.
Rigby  WF; Ball  ED; Guyre  PM; Fanger  MW 《Blood》1985,65(4):858-861
Interferons (IFNs) have been shown to have significant effects on hematopoietic cell growth. Previous studies defining these effects have utilized mouse and human alpha-, beta-, and gamma-IFN isolated from supernatants of stimulated cells. Despite purification, the possible presence of other lymphokines and soluble factors remains a concern. In this study, the effects of gene-cloned alpha- and gamma-IFN on colony- forming units of granulocyte/macrophage (CFU-GM) progenitors cultured from the peripheral blood of normal volunteers were examined. In addition, blast cell colonies from one patient with acute myelogenous leukemia (AML) were studied. The growth of normal CFU-GM and AML blast cell colonies was inhibited in a dose-dependent manner by gamma- and alpha-IFN. gamma-IFN was ten to 100 times more potent than alpha-IFN in that this species of IFN reduced colony formation by greater than 50% at concentrations of less than 15 antiviral U/mL. The effects of gamma- IFN were neutralized by a monoclonal antibody specific for gamma-IFN. These in vitro studies indicate that human gamma-IFN may be an important modulator of myelopoiesis. Although these data indicate a possible efficacy of gamma-IFN in the treatment of AML, the in vitro results should be considered for their in vivo significance.  相似文献   
64.
INTRODUCTION Clinical factors contributing to the therapeutic challenge of hepatocellular carcinoma (HCC) are manifold :tumors arise often in patients with compromised liver function ,therefore limiting therapeutic options ;symptoms develop only at later stages of tumor progression ,and tumors tend to invade normal stuctures or occur in multiple locations simultaneously.  相似文献   
65.
ObjectiveNon-echo planar diffusion weighted magnetic resonance imaging is a reliable surveillance tool of residual cholesteatoma nowadays. It is not known whether the material of the ossicular chain prosthesis modifies the sensitivity and specificity of MRI in these cases. The aim of the study was to compare the sensitivity, specificity and a localization-specific accuracy of non-EPI DW MRI sequences for residual cholesteatoma in the following 3 subgroups: patients with titanium ossicular prosthesis (group T), with autologous cortical bone columella (group A) or without any reconstruction (group WR) of hearing bones.MethodsThis prospective study covered 28 cases with cholesteatoma of the middle ear undergone second-look surgery, who had preoperative PROPELLER DW-MRI. Surgical findings were compared to the results of the DWI-MRI.ResultsThe overall sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were: 0.76-0.8-0.76-0.8. Group T, group A and group WR sensitivity was 0.83-0.6-1, specificity: 0.75-0.75-0.85, PPV: 0.83-0.75-0.66, NPV: 0.75-0.6-1. Overall accuracy was 0.78. Size of missed cholesteatoma was 2-4 mm (mean: 2.66±1.15).ConclusionsVarious materials are suitable for ossicular chain reconstruction. The poor detectability of residual or recurrent cholesteatoma in the middle ears reconstructed with autologous bony prosthesis may still claim second-look surgery instead of the usage of non- EPI DWI sequences independently in these patients.  相似文献   
66.
GeroScience - The global impact of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is significant in terms of public health effects and its long-term socio-economic...  相似文献   
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Microsatellite instability-high (MSI-H) and tumor mutational burden (TMB) are predictive biomarkers for immune-checkpoint inhibitors (ICIs). Still, the relationship between the underlying cause(s) of MSI and TMB in tumors remains poorly defined. We investigated associations of TMB to mismatch repair (MMR) protein expression patterns by immunohistochemistry (IHC) and MMR mutations in a diverse sample of tumors. Hypothesized differences were identified by the protein/gene affected/mutated and the tumor histology/primary site. Overall, 1057 MSI-H tumors were identified from the 32 932 tested. MSI was examined by NGS using 7000+ target microsatellite loci. TMB was calculated using only nonsynonymous missense mutations sequenced with a 592-gene panel; a subset of MSI-H tumors also had MMR IHC performed. Analyses examined TMB by MMR protein heterodimer impacted (loss of MLH1/PMS2 vs. MSH2/MSH6 expression) and gene-specific mutations. The sample was 54.6% female; mean age was 63.5 years. Among IHC tested tumors, loss of co-expression of MLH1/PMS2 was more common (n = 544/705, 77.2%) than loss of MSH2/MSH6 (n = 81/705, 11.5%; P < .0001), and was associated with lower mean TMB (MLH1/PMS2: 25.03 mut/Mb vs MSH2/MSH6 46.83 mut/Mb; P < .0001). TMB also varied by tumor histology: colorectal cancers demonstrating MLH1/PMS2 loss had higher TMBs (33.14 mut/Mb) than endometrial cancers (20.60 mut/Mb) and other tumors (25.59 mut/Mb; P < .0001). MMR gene mutations were detected in 42.0% of tumors; among these, MSH6 mutations were most common (25.7%). MSH6 mutation patterns showed variability by tumor histology and TMB. TMB varies by underlying cause(s) of MSI and tumor histology; this heterogeneity may contribute to differences in response to ICI.  相似文献   
70.
A major challenge in the development of anticancer therapies is the considerable time and resources needed for conducting randomized clinical trials (RCT). There is a need for more efficient RCT designs that accelerate development, minimize costs, and make trials more appealing to patients. We review the statistical and logistical characteristics of multi-arm designs that compare several experimental treatments to a common control arm. In particular, we present a rationale for not requiring multiplicity adjustment in multi-arm trials that are designed for logistical efficiency. Relative to conducting separate RCTs for each experimental agent, this multi-arm design is shown to require a lower total sample size than multiple two-arm trials.  相似文献   
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