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排序方式: 共有2475条查询结果,搜索用时 31 毫秒
41.
de Haas M; Kerst JM; van der Schoot CE; Calafat J; Hack CE; Nuijens JH; Roos D; van Oers RH; von dem Borne AE 《Blood》1994,84(11):3885-3894
In four healthy volunteers, we analyzed in detail the immediate in vivo effects on circulating neutrophils of subcutaneous administration of 300 micrograms of granulocyte colony-stimulating factor (G-CSF). Neutrophil activation was assessed by measurement of degranulation. Mobilization of secretory vesicles was shown by a decrease in leukocyte alkaline phosphatase content of the circulating neutrophils. Furthermore, shortly postinjection, Fc gamma RIII was found to be upregulated from an intracellular pool that we identified by immunoelectron microscopy as secretory vesicles. Intravascular release of specific granules was shown by increased plasma levels of lactoferrin and by upregulation of the expression of CD66b and CD11b on circulating neutrophils. Moreover, measurement of fourfold elevated plasma levels of elastase, bound to its physiologic inhibitor alpha 1- antitrypsin, indicated mobilization of azurophil granules. However, no expression of CD63, a marker of azurophil granules, was observed on circulating neutrophils. G-CSF--induced mobilization of secretory vesicles and specific granules could be mimicked in whole blood cultures in vitro, in contrast to release of azurophil granules. Therefore, we postulate that the most activated neutrophils leave the circulation, as observed shortly postinjection, and undergo subsequent stimulation in the endothelial microenvironment, resulting in mobilization of azurophil granules. Our data demonstrate that G-CSF should be regarded as a potent immediate activator of neutrophils in vivo. 相似文献
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43.
Rajendra Kumar Gokhroo Kaul Anushri M.T. Tarik C. Kailash N. Rajesh K. Ashish G. Manish C. Subhash 《Indian heart journal》2021,73(2):205-210
BackgroundSacubitril/Valsartan (ARNI) has now class 1 recommendation for treatment of heart failure with reduced ejection fraction (HFrEF). It has been shown to reduce cardiovascular morbidity & mortality in Heart failure with reduced ejection fraction (HFrEF) and significant improvement in all echocardiographic parameters besides TEI index. Tei index is a marker of inflammation, myocardial cell metabolism and its contractile function has not been evaluated as a distinctive entity so we took up this study to evaluate the effects of ARNI on the LV functions using two dimensional (2D)ECHO parameters in Indian population and to assess TEI index for myocardial function.Methods256 patients with class II, III or IV HF and EF<40% were enrolled. 171(66.8%) were males and 85(33.2%) were females. Patients were evaluated at baseline, 6 and 12 months for LVEF, LV mass &,LVMPI. Drug was discontinued in 2 patients due to angioedema, in 5 patients due to acute kidney injury and in 2 patients due to hypotension. LV mass measurement done by linear echocardiographic method and Flow Doppler method used for TEI index calculation.ResultsBaseline parameters in 247 patients were mean EF = 26.33 ± 6.28%, mean LV mass = 270.84 ± 68.94 gm, mean Tei Index = 0.852 ± 0.22. ARNI use was associated with an average gradual increase in EF, from a mean baseline of 26.33 ± 6.28% to 33.88 ± 7.73%(p = 0.000001) after 1 year of treatment. There was a significant progressive reduction of 57.97 g/m2 in mean LV mass index after 1 year of treatment (p = 0.000001).TEI index showed significant reduction from baseline mean 0.85 ± 0.22 to 0.70 ± 0.12(p = 0.000001)after 1 year of treatment.ConclusionUse of ARNI as additive adjunct to standard care of treatment resulted in significant progressive decline in LV mass and increase in TEI index. 相似文献
44.
Rajagopalan S Brook R Mehta RH Supiano M Pitt B 《The American journal of cardiology》2002,89(5):562-566
Aging is associated with progressive deterioration in endothelial function. We hypothesized that losartan may represent a useful therapeutic strategy to ameliorate endothelial function in aged subjects. Eighteen healthy older subjects (mean age 75 +/- 3 years) were prospectively randomized in a double-blind, crossover fashion to receive either losartan 50 mg/day or placebo for 6 weeks. Subjects were switched to the opposite arm after a 2- week washout period. Flow-mediated dilation (FMD) in the brachial artery and plasma levels of vascular cell adhesion molecule-1, intercellular adhesion molecule (ICAM), moncocyte chemoattractant 1 protein, and E-selectin were measured in both arms at the beginning and end of the 6-week period. Losartan resulted in a 6-mm Hg decrease in systolic blood pressure (from 130 +/- 12 to 124 +/- 13 mm Hg), which was no different from placebo (132 +/- 12 to 127 +/- 13 mm Hg). FMD increased from 3.1 +/- 0.6% to 3.9 +/- 0.6% after losartan, and decreased from 3.3 +/- 0.3% to 2.4 +/- 0.6% after placebo (p = NS for both). In contrast, losartan reduced circulating concentrations of vascular cell adhesion molecule 1 (750 +/- 73 to 572 +/- 39), ICAM (405 +/- 26 to 196 +/- 10), and moncocyte chemoattractant 1 protein (560 +/- 56 to 423 +/- 35) (p <0.01 for all by analysis of variance), but not E-selectin. On univariate analyses, the strongest predictor of baseline endothelial function and change in FMD with losartan was low-density lipoprotein. There was a negative correlation between baseline endothelial function and change in FMD in response to losartan (r(2) = -0.75, p = 0.0003). Baseline ICAM levels alone significantly correlated with low-density lipoprotein cholesterol (r(2) = 0.54, p = 0.02) and weakly correlated with total cholesterol (r(2) = 0.47, p = 0.05). Thus, administration of losartan for a duration of 6 weeks has favorable effects on inflammatory markers in healthy older subjects, but does not alter peripheral conduit endothelial function. 相似文献
45.
CE Faggons C Mabedi CG Shores S Gopal 《Malawi medical journal : the journal of Medical Association of Malawi》2015,27(3):79-87
Aim
Review the literature from 1990 to 2013 to determine known anatomic sites, risk factors, treatments, and outcomes of head and neck squamous cell carcinoma (HNSCC) in sub-Saharan Africa.Methods
Using a systematic search strategy, literature pertaining to HNSCC in sub-Saharan Africa was reviewed and patient demographics, anatomic sites, histology, stage, treatment, and outcomes were abstracted. The contributions of human immunodeficiency virus (HIV), human papillomavirus (HPV) and behavioural risk factors to HNSCC in the region were assessed.Results
Of the 342 papers identified, 46 were utilized for review, including 8611 patients. In sub-Saharan Africa, the oropharyngeal/oral cavity was found to be the most common site, with 7750 cases (90% of all cases). Few papers distinguished oropharyngeal from oral cavity, making identification of possible HPV-associated oropharyngeal squamous cell carcinoma (SCC) difficult. SCC of the nasopharynx, nasal cavity, or paranasal sinuses was identified in 410 patients (4.8% of all cases). Laryngeal SCC was found in 385 patients (4.5% of all cases), and only 66 patients (0.8% of all cases) with hypopharyngeal SCC were identified. In 862 patients with data available, 43% used tobacco and 42% used alcohol, and reported use varied widely and was more common in laryngeal SCC than that of the oropharyngeal/oral cavity. Toombak and kola nut use was reported to be higher in patients with HNSCC. Several papers reported HIV-positive patients with HNSCC, but it was not possible to determine HNSCC prevalence in HIV-positive compared to negative patients. Reports of treatment and outcomes were rare.Conclusions
The oropharyngeal/oral cavity was by far the most commonly reported site of HNSCC reported in sub-Saharan Africa. The roles of risk factors in HNSCC incidence in sub-Saharan Africa were difficult to delineate from the available studies, but a majority of patients did not use tobacco and alcohol. 相似文献46.
Sunil R. Kadam Rajendra P. Panmand Shashikant Tekale Supriya Khore Chiaki Terashima Suresh W. Gosavi Akira Fujishima Bharat B. Kale 《RSC advances》2018,8(25):13764
Herein, a facile in situ solvothermal technique for the synthesis of a CdMoO4/graphene composite photocatalyst is reported. Graphene oxide (GO) was synthesised by an improved Hummers'' method and was further used for the in situ synthesis of graphene via GO reduction and the formation of a CdMoO4 nanowire/graphene composite. The structural phase formation of tetragonal CdMoO4 was confirmed from X-ray diffraction measurements. The small nanoparticle assembled nanowires, prismatic microsphere morphology and crystalline nature of the synthesized material were investigated using field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). Due to its unique morphology and stability, the CdMoO4/graphene composite was used as a photocatalyst for H2O splitting. In comparison to pristine CdMoO4, the CdMoO4/graphene composite showed the best hydrogen evolution rate, i.e. 3624 μmole h−1 g−1, with an apparent quantum yield of 30.5%. The CdMoO4/graphene composite has a higher photocatalytic activity due to the inhibition of charge carrier recombination. H2 production measurements showed that the ternary semiconductor/graphene composite has enhanced photocatalytic activity for H2 generation.Herein, a facile in situ solvothermal technique for the synthesis of a CdMoO4/graphene composite photocatalyst for hydrogen generation under natural solar light. 相似文献
47.
48.
Rajendra?Prasad Yashbir?Singh?ShivayEmail author 《Proceedings of the National Academy of Sciences, India. Section B.》2018,88(2):429-434
Sulphur is now recognized as the fourth major plant nutrient after N, P and K globally. Sulphur in soils comes from the sulphur containing minerals present in parent materials from which the soils are derived and from the plants and animals residues or from the external addition of elemental S or its minerals. Sulphur enters the biological systems from soil through microbial activities involving mineralization of organic matter, immobilization, oxidation and reduction. Plants take up sulphur only as SO 4 = and reduce it to form S containing amino acids and other compounds. Amino acid cysteine is the source of sulphur for most other S-compounds in plants. Sulphur containing vitamin thiamine (Vitamin B1) is also synthesized only in plants and not in humans or other animals. Plants also produce vitamin biotin and a number of S-containing metabolites including glutathione, glucosinolates and alliin/allicin. Sulphur deficiency in wheat can lead to poor baking quality and in oilseeds it can lead to reduced oil content and yield. Sulphur is taken in as sulphur containing amino acids (SAAs) cysteine and methionine by human beings. The recommended dietary allowance for SAAs for humans is 14 mg kg?1 body weight. Lack of sulphur can lead to arthritis, muscle and joint stiffness, spondylitis, etc. Dietary supplements containing (chondroitin sulphate, glucosamine sulphate, methylsulfonylmethane etc.) can be beneficial in the treatment of joint diseases. 相似文献
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50.
Ranucci M Ballotta A Kunkl A De Benedetti D Kandil H Conti D Mollichelli N Bossone E Mehta RH 《The American journal of cardiology》2008,101(8):1112-1118
Postoperative acute renal failure (ARF) is not uncommon after cardiac surgery and after angiography. However, limited information exists regarding the influence of the interval between cardiac catheterization and subsequent cardiac surgery and amount of contrast agent used during this procedure on the occurrence of postoperative ARF. Data for 423 consecutive adult patients who underwent elective cardiac surgery after cardiac catheterization were examined retrospectively. The influence of interval between cardiac catheterization and cardiac surgery on postoperative ARF (defined as postoperative serum creatinine > or =2 times baseline and >2 mg/dl and/or need for renal replacement therapy) was evaluated using multivariable logistic regression. ARF occurred in 24 patients (5.7%). Median time to angiography was 2 days (interquartile range 1 to 4.5), and median dose of contrast used was 1.36 ml/kg (interquartile range 1.12 to 1.69). Surgery on the day of cardiac catheterization was independently associated with increased risk of ARF (adjusted odds ratio 3.1, 95% confidence interval 1.1 to 8.8). This risk of ARF was highest in patients who underwent surgery on the same day as angiography and with a dose of contrast higher than median (14.6%) and lowest when surgery was delayed beyond 1 day of angiography and contrast dose was median or less (2.4%; adjusted odds ratio for same-day surgery and dose higher than median 4.2, 95% confidence interval 1.2 to 14.2). Cardiac surgery performed on the day of cardiac catheterization and higher dose of contrast agent used were both independently associated with increased risk of postoperative ARF. In conclusion, these findings suggest that delaying cardiac surgery beyond 24 hours of exposure to contrast agents (when feasible) and minimizing the use of these agents have significant potential to decrease the incidence of postoperative ARF in patients undergoing elective cardiac surgery. 相似文献