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71.
BackgroundThere is some evidence that university students are at higher risk of depression; but rates have been found to vary widely across different countries, and there have been few surveys in representative samples. This study was carried out to assess the reliability of the Arabic-language Zagazig Depression Scale (ZDS) in a sample of Egyptian university students and to use the ZDS to assess the prevalence of depression.MethodsThe study was a cross-sectional survey of a representative sample of 988 undergraduate students from Assiut University, Egypt (response rate, 82.3%). Prevalence of depressive symptoms was assessed using the ZDS, a self-report Arabic-language version of the Hamilton Rating Scale, modeled on the Carroll Rating Scale for Depression.ResultsParticipants had a mean ZDS score of 17.8 (±9.0) out of a possible maximum score of 46. Using the recommended cutoffs for the ZDS, 37.6% of the students were found to have at least moderate depression, with 71% exceeding the cutoff for mild depression. The internal consistency of the ZDS was excellent (Cronbach α = 0.904), as was the split-half correlation coefficient.ConclusionThis survey revealed a worryingly high rate of depressive symptoms in a representative sample of Egyptian university students. The ZDS is a reliable and acceptable tool for assessing mental health in a university population. 相似文献
72.
Rat carotid arteries were injured electrically (350 V, 2 mA DC for 5 min) before and after the intravenous administration of heparin (1,000 U/kg), VK 744 (25, 50, 100 mg/kg) ASA (100, 200 mg/kg) and sulfinpyrazone (50, 100, 150, 200 mg/kg). Thrombus growth was quantified by recording arterial temperature change distal to the injury. Heparin completely blocked thrombus formation in most experiments. All other agents exhibited antithrombotic activity with sulfinpyrazone being most potent. None was as effective as heparin. This model may be a useful tool for screening antithrombotic drugs. 相似文献
73.
Mitochondrial DNA (mtDNA) repair occurs in all eukaryotic organisms and is essential for the maintenance of mitochondrial function. Evidence from both humans and yeast suggests that mismatch repair is one of the pathways that functions in overall mtDNA stability. In the mitochondria of the yeast Saccharomyces cerevisiae, the presence of a homologue to the bacterial MutS mismatch repair protein, MSH1, has long been known to be essential for mitochondrial function. The mechanisms for which it is essential are unclear, however. Here, we analyze the effects of two point mutations, msh1-F105A and msh1-G776D, both predicted to be defective in mismatch repair; and we show that they are both able to maintain partial mitochondrial function. Moreover, there are significant differences in the severity of mitochondrial disruption between the two mutants that suggest multiple roles for Msh1p in addition to mismatch repair. Our overall findings suggest that these additional predicted functions of Msh1p, including recombination surveillance and heteroduplex rejection, may be primarily responsible for its essential role in mtDNA stability. 相似文献
74.
Borman PJ Chatfield MJ Crowley EL Eckers C Elder DP Francey SW Laures AM Wolff JC 《Journal of pharmaceutical and biomedical analysis》2008,48(4):1082-1089
This work describes the development of a liquid chromatography tandem mass spectrometry (LC-MS/MS) assay for a highly toxic impurity, FMTP (4-(4-fluorophenyl)-1-methyl-1,2,3,6-tetrahydropyridine), in paroxetine active pharmaceutical ingredient (API), followed by the subsequent validation of the methodology and transfer into a global production/quality control environment. The method was developed to achieve a detection limit of 10ppb mass fraction of FMTP in paroxetine API. An LC-MS/MS method was chosen because it provided the required sensitivity and selectivity with minimal sample preparation. This paper discusses the issues with transferring such complex methodology to a production environment. Linearity, repeatability and reproducibility of the method were demonstrated. This work shows that it is possible using the same approach that would be used for the transfer of any analytical method from R&D to a manufacturing environment. 相似文献
75.
76.
Stephanie S. Young Kazi Rahman Paul Hainsworth Shona Murray Maniram Ragbir 《European journal of plastic surgery》2016,39(3):213-215
A hindquarter amputation and hemipelvectomy for recurrent malignancy presents a reconstructive challenge to the plastic surgeon. Tumour resection leaves a considerable defect, with exposure of bone, neurovascular structures, pelvic and abdominal organs. A free lower leg fillet flap is a recognised method of providing soft tissue coverage, but ischaemic time is often lengthy as described in the literature. We present a unique method of providing soft tissue coverage using a free lower leg fillet flap, and minimising ischaemic time by banking the flap on the ulnar artery during the hindquarter amputation and tumour resection.Level of Evidence: Level V, therapeutic study. 相似文献
77.
Morten Mørk Shona Pedersen Jaco Botha Sigrid Marie Lund 《Scandinavian journal of clinical and laboratory investigation》2016,76(5):349-360
Background: Nanoparticle tracking analysis (NTA) and tunable resistive pulse sensing (TRPS) enable measurement of extracellular vesicles (EVs) in blood plasma but also measure other particles present in plasma. Complete isolation of EVs from similarly sized particles with full EV recovery is currently not possible due to limitations in existing isolation techniques.Aim: This study aimed to evaluate preanalytical, analytical, and biological variation of particle measurements with NTA and TRPS on blood plasma.Methods: Blood from 20 healthy subjects was sampled in the fasting and postprandial state. Platelet free plasma (PFP) was analyzed immediately and after a freeze-thaw cycle. Additionally, the effect of prandial state and a freeze-thaw cycle on EV-enriched particle fractions obtained via size-exclusion chromatography (SEC) was examined.Results: We observed analytical linearity in the range of 1.0–10.0?×?108 particles/mL for NTA and 1.0?×?108–1.8?×?109 particles/mL for TRPS. The analytical variation was generally below 10%. A considerable intra- and inter-individual variation was demonstrated with estimated reference intervals of 1.4?×?1011–1.2?×?1012 particles/mL for NTA and 1.8?×?108–1.6?×?109 particles/mL for TRPS. Food intake and to a lesser extent a freeze-thaw cycle affected particle populations in PFP and, similarly, in EV-enriched fractions.Conclusion: In this study NTA and TRPS enabled acceptably precise concentration and size measurement of submicron particles in PFP. An appreciable intra- and inter-individual biological variation was observed. In studies on particle populations in PFP or EV-enriched fractions, we recommend analysis of fresh, fasting samples. 相似文献
78.
Objectives
The aim of the study was to determine if Lyprinol® is effective in reducing pain, indicators of inflammation and muscle damage, and in turn improving performance in well trained athletes suffering from delayed onset muscle soreness (DOMS).Design
A double blind randomised placebo controlled trial.Setting
Twenty well trained male volunteers, matched by VO2 max were randomly assigned to consume 200 mg of Lyprinol® or an indistinguishable placebo daily for 8 weeks prior to a downhill treadmill running episode designed to induce DOMS.Main outcome measures
Performance measures (Kin-Com, counter movement and squat jump), pain assessments (visual analogue scale, algometer) and blood analyses (Interleukin-1, Interleukin-6, Interleukin-10, tumour necrosis factor-α, C-reactive protein, myoglobin, creatine kinase) were assessed at 7 time points over 5 days (pre, post, 4, 24, 48, 72 and 96 h after the downhill run).Results
No statistically significant differences were identified in any parameters between the active and placebo groups at any time point.Conclusion
After 2 months ingestion of Lyprinol® at the currently recommended dosage (200 mg/day) and a demanding eccentric exercise intervention, Lyprinol® did not convincingly affect DOMS and indicators of muscle damage. 相似文献79.
Andrew M. Jackson Anton B. Alexandrov Shona C. Gribben K. Esuvarnathan Keith James 《International journal of cancer. Journal international du cancer》1993,55(6):921-925
Intercellular adhesion molecule-1 (ICAM-1) is one of 3 major ligands for the β2 integrin leucocyte function-associated antigen- I (LFA-1). Several reports have emerged describing soluble forms of ICAM-1 in association with normal and pathological states (e.g., malignancy). In this study we have identified the secretion of soluble ICAM-1 in tissue culture supernatants from bladder tumour monolayers and in the urine of patients receiving intravesical BCG immunotherapy for superficial bladder cancer. In vitro, small amounts of sICAM-1 were detected in the tissue culture supernatants of bladder cancer cells, known to constitutively express ICAM-1. Following stimulation with interferon γ, the levels of sICAM-1 increased inversely to the levels of cell surface ICAM-1, suggesting shedding. Induction and augmentation of cell surface ICAM-1 required de novo mRNA and protein synthesis. However, treatment with cycloheximide, after stimulation with IFN-γ, resulted in increased levels of membrane associated ICAM-1. Correspondingly, the level of sICAM-1 in the supernatant was low in comparison with controls, suggesting that cycloheximide acted via stabilization of membrane ICAM-1 or via prevention of some enzymatic cleavage event. In vivo, sICAM-1 can be detected at high levels in patients' urine following immunotherapy of bladder cancer with intravesically administered BCG organisms. Production of sICAM-1 is transient and occurs only in the first 12 hr following instillation. Furthermore, production of sICAM-1 is heterogeneous as some patients fail to produce any at all. If the source of sICAM-1 is the bladder tumour per se, then its detection in urine could indicate a response of the tumour to immunotherapy and indeed may prove a useful indicator of clinical response. 相似文献
80.
Lamagni TL Neal S Keshishian C Alhaddad N George R Duckworth G Vuopio-Varkila J Efstratiou A 《Emerging infectious diseases》2008,14(2):202-209
As part of a Europe-wide initiative to explore current epidemiologic patterns of severe disease caused by Streptococcus pyogenes, the United Kingdom undertook enhanced population-based surveillance during 2003-2004. A total of 3,775 confirmed cases of severe S. pyogenes infection were identified over 2 years, 3.33/100,000 population, substantially more than previously estimated. Skin/soft tissue infections were the most common manifestation (42%), followed by respiratory tract infections (17%). Injection drug use was identified as a risk factor for 20% of case-patients. One in 5 infected case-patients died within 7 days of diagnosis; the highest mortality rate was for cases of necrotizing fasciitis (34%). Nonsteroidal antiinflammatory drugs, alcoholism, young age, and infection with emm/M3 types were independently associated with increased risk for streptococcal toxic shock syndrome. Understanding the pattern of these diseases and predictors of poor patient outcome will help with identification and assessment of the potential effect of targeted interventions. 相似文献